Space Station technology testbed: 2010 deep space transport

Science.gov (United States)

Holt, Alan C.

1993-01-01

A space station in a crew-tended or permanently crewed configuration will provide major R&D opportunities for innovative, technology and materials development and advanced space systems testing. A space station should be designed with the basic infrastructure elements required to grow into a major systems technology testbed. This space-based technology testbed can and should be used to support the development of technologies required to expand our utilization of near-Earth space, the Moon and the Earth-to-Jupiter region of the Solar System. Space station support of advanced technology and materials development will result in new techniques for high priority scientific research and the knowledge and R&D base needed for the development of major, new commercial product thrusts. To illustrate the technology testbed potential of a space station and to point the way to a bold, innovative approach to advanced space systems' development, a hypothetical deep space transport development and test plan is described. Key deep space transport R&D activities are described would lead to the readiness certification of an advanced, reusable interplanetary transport capable of supporting eight crewmembers or more. With the support of a focused and highly motivated, multi-agency ground R&D program, a deep space transport of this type could be assembled and tested by 2010. Key R&D activities on a space station would include: (1) experimental research investigating the microgravity assisted, restructuring of micro-engineered, materials (to develop and verify the in-space and in-situ 'tuning' of materials for use in debris and radiation shielding and other protective systems), (2) exposure of microengineered materials to the space environment for passive and operational performance tests (to develop in-situ maintenance and repair techniques and to support the development, enhancement, and implementation of protective systems, data and bio-processing systems, and virtual reality and

Reusable Nanocomposite Membranes for the Selective Recovery of Nutrients in Space, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Through the STTR program, NanoSonic and Virginia Tech will create low-cost, reusable membranes that selectively capture and recycle nutrients (e.g., N, P, K) from...

Transportable Payload Operations Control Center reusable software: Building blocks for quality ground data systems

Science.gov (United States)

Mahmot, Ron; Koslosky, John T.; Beach, Edward; Schwarz, Barbara

1994-01-01

The Mission Operations Division (MOD) at Goddard Space Flight Center builds Mission Operations Centers which are used by Flight Operations Teams to monitor and control satellites. Reducing system life cycle costs through software reuse has always been a priority of the MOD. The MOD's Transportable Payload Operations Control Center development team established an extensive library of 14 subsystems with over 100,000 delivered source instructions of reusable, generic software components. Nine TPOCC-based control centers to date support 11 satellites and achieved an average software reuse level of more than 75 percent. This paper shares experiences of how the TPOCC building blocks were developed and how building block developer's, mission development teams, and users are all part of the process.

A two stage launch vehicle for use as an advanced space transportation system for logistics support of the space station

Science.gov (United States)

1987-01-01

This report describes the preliminary design specifications for an Advanced Space Transportation System consisting of a fully reusable flyback booster, an intermediate-orbit cargo vehicle, and a shuttle-type orbiter with an enlarged cargo bay. It provides a comprehensive overview of mission profile, aerodynamics, structural design, and cost analyses. These areas are related to the overall feasibility and usefullness of the proposed system.

Orbiting Depot and Reusable Lander for Lunar Transportation

Science.gov (United States)

Petro, Andrew

2009-01-01

A document describes a conceptual transportation system that would support exploratory visits by humans to locations dispersed across the surface of the Moon and provide transport of humans and cargo to sustain one or more permanent Lunar outpost. The system architecture reflects requirements to (1) minimize the amount of vehicle hardware that must be expended while maintaining high performance margins and (2) take advantage of emerging capabilities to produce propellants on the Moon while also enabling efficient operation using propellants transported from Earth. The system would include reusable single- stage lander spacecraft and a depot in a low orbit around the Moon. Each lander would have descent, landing, and ascent capabilities. A crew-taxi version of the lander would carry a pressurized crew module; a cargo version could carry a variety of cargo containers. The depot would serve as a facility for storage and for refueling with propellants delivered from Earth or propellants produced on the Moon. The depot could receive propellants and cargo sent from Earth on a variety of spacecraft. The depot could provide power and orbit maintenance for crew vehicles from Earth and could serve as a safe haven for lunar crews pending transport back to Earth.

The Cost-Optimal Size of Future Reusable Launch Vehicles

Science.gov (United States)

Koelle, D. E.

2000-07-01

The paper answers the question, what is the optimum vehicle size — in terms of LEO payload capability — for a future reusable launch vehicle ? It is shown that there exists an optimum vehicle size that results in minimum specific transportation cost. The optimum vehicle size depends on the total annual cargo mass (LEO equivalent) enviseaged, which defines at the same time the optimum number of launches per year (LpA). Based on the TRANSCOST-Model algorithms a wide range of vehicle sizes — from 20 to 100 Mg payload in LEO, as well as launch rates — from 2 to 100 per year — have been investigated. It is shown in a design chart how much the vehicle size as well as the launch rate are influencing the specific transportation cost (in MYr/Mg and USS/kg). The comparison with actual ELVs (Expendable Launch Vehicles) and Semi-Reusable Vehicles (a combination of a reusable first stage with an expendable second stage) shows that there exists only one economic solution for an essential reduction of space transportation cost: the Fully Reusable Vehicle Concept, with rocket propulsion and vertical take-off. The Single-stage Configuration (SSTO) has the best economic potential; its feasibility is not only a matter of technology level but also of the vehicle size as such. Increasing the vehicle size (launch mass) reduces the technology requirements because the law of scale provides a better mass fraction and payload fraction — practically at no cost. The optimum vehicle design (after specification of the payload capability) requires a trade-off between lightweight (and more expensive) technology vs. more conventional (and cheaper) technology. It is shown that the the use of more conventional technology and accepting a somewhat larger vehicle is the more cost-effective and less risky approach.

Study of extraterrestrial disposal of radioactive wastes. Part 1: Space transportation and destination considerations for extraterrestrial disposal of radioactive wastes. [feasibility of using space shuttle

Science.gov (United States)

Thompson, R. L.; Ramler, J. R.; Stevenson, S. M.

1974-01-01

A feasibility study of extraterrestrial disposal of radioactive waste is reported. This report covers the initial work done on only one part of the NASA study, that evaluates and compares possible space destinations and space transportation systems. The currently planned space shuttle was found to be more cost effective than current expendable launch vehicles by about a factor of 2. The space shuttle requires a third stage to perform the waste disposal missions. Depending on the particular mission, this third stage could be either a reusable space tug or an expendable stage such as a Centaur.

14 CFR 437.67 - Tracking a reusable suborbital rocket.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Tracking a reusable suborbital rocket. 437... a reusable suborbital rocket. A permittee must— (a) During permitted flight, measure in real time the position and velocity of its reusable suborbital rocket; and (b) Provide position and velocity...

Safety And Promotion in the Federal Aviation Administration- Enabling Safe and Successful Commercial Space Transportation

Science.gov (United States)

Repcheck, Randall J.

2010-09-01

The United States Federal Aviation Administration’s Office of Commercial Space Transportation(AST) authorizes the launch and reentry of expendable and reusable launch vehicles and the operation of launch and reentry sites by United States citizens or within the United States. It authorizes these activities consistent with public health and safety, the safety of property, and the national security and foreign policy interests of the United States. In addition to its safety role, AST has the role to encourage, facilitate, and promote commercial space launches and reentries by the private sector. AST’s promotional role includes, among other things, the development of information of interest to industry, the sharing of information of interest through a variety of methods, and serving as an advocate for Commercial Space Transportation within the United States government. This dual safety and promotion role is viewed by some as conflicting. AST views these two roles as complementary, and important for the current state of commercial space transportation. This paper discusses how maintaining a sound safety decision-making process, maintaining a strong safety culture, and taking steps to avoid complacency can together enable safe and successful commercial space transportation.

Space transportation and destination considerations for extraterrestrial disposal of radioactive waste

Science.gov (United States)

Zimmerman, A. V.; Thompson, R. L.; Lubick, R. J.

1973-01-01

A feasibility study is summarized of extraterrestrial (space) disposal of radioactive waste. The initial work on the evaluation and comparison of possible space destinations and launch vehicles is reported. Only current or planned space transportation systems were considered. The currently planned space shuttle was found to be more cost effective than current expendable launch vehicles, by about a factor of two. The space shuttle will require a third stage to perform the disposal missions. Depending on the particular mission this could be either a reusable space tug or an expendable stage such as a Centaur. Of the destinations considered, high earth orbits (between geostationary and lunar orbit altitudes), solar orbits (such as a 0.90 AU circular solar orbit) or a direct injection to solar system escape appear to be the best candidates. Both earth orbits and solar orbits have uncertainties regarding orbit stability and waste package integrity for times on the order of a million years.

Assessment of the Feasibility of Innovative Reusable Launchers

Science.gov (United States)

Chiesa, S.; Corpino, S.; Viola, N.

The demand for getting access to space, in particular to Low Earth Orbit, is increasing and fully reusable launch vehicles (RLVs) are likely to play a key role in the development of future space activities. Up until now this kind of space systems has not been successfully carried out: in fact today only the Space Shuttle, which belongs to the old generation of launchers, is operative and furthermore it is not a fully reusable system. In the nineties many studies regarding advanced transatmospheric planes were started, but no one was accomplished because of the technological problems encountered and the high financial resources required with the corresponding industrial risk. One of the most promising project was the Lockheed Venture Star, which seemed to have serious chances to be carried out. Anyway, if this ever happens, it will take quite a long time thus the operative life of Space Shuttle will have to be extended for the International Space Station support. The purpose of the present work is to assess the feasibility of different kinds of advanced reusable launch vehicles to gain access to space and to meet the requirements of today space flight needs, which are mainly safety and affordability. Single stage to orbit (SSTO), two stage to orbit (TSTO) and the so called "one and a half" stage to orbit vehicles are here taken into account to highlight their advantages and disadvantages. The "one and a half" stage to orbit vehicle takes off and climbs to meet a tanker aircraft to be aerially refuelled and then, after disconnecting from the tanker, it flies to reach the orbit. In this case, apart from the space vehicle, also the tanker aircraft needs a dedicated study to examine the problems related to the refuelling at high subsonic speeds and at a height near the tropopause. Only winged vehicles which take off and land horizontally are considered but different architectural layouts and propulsive configurations are hypothesised. Unlike the Venture Star, which

The rationale/benefits of nuclear thermal rocket propulsion for NASA's lunar space transportation system

Science.gov (United States)

Borowski, Stanley K.

1994-09-01

The solid core nuclear thermal rocket (NTR) represents the next major evolutionary step in propulsion technology. With its attractive operating characteristics, which include high specific impulse (approximately 850-1000 s) and engine thrust-to-weight (approximately 4-20), the NTR can form the basis for an efficient lunar space transportation system (LTS) capable of supporting both piloted and cargo missions. Studies conducted at the NASA Lewis Research Center indicate that an NTR-based LTS could transport a fully-fueled, cargo-laden, lunar excursion vehicle to the Moon, and return it to low Earth orbit (LEO) after mission completion, for less initial mass in LEO than an aerobraked chemical system of the type studied by NASA during its '90-Day Study.' The all-propulsive NTR-powered LTS would also be 'fully reusable' and would have a 'return payload' mass fraction of approximately 23 percent--twice that of the 'partially reusable' aerobraked chemical system. Two NTR technology options are examined--one derived from the graphite-moderated reactor concept developed by NASA and the AEC under the Rover/NERVA (Nuclear Engine for Rocket Vehicle Application) programs, and a second concept, the Particle Bed Reactor (PBR). The paper also summarizes NASA's lunar outpost scenario, compares relative performance provided by different LTS concepts, and discusses important operational issues (e.g., reusability, engine 'end-of life' disposal, etc.) associated with using this important propulsion technology.

Air Force Reusable Booster System: A Quick-look, Design Focused Modeling and Cost Analysis Study

Science.gov (United States)

Zapata, Edgar

2011-01-01

This paper presents a method and an initial analysis of the costs of a reusable booster system (RBS) as envisioned by the US Department of Defense (DoD) and numerous initiatives that form the concept of Operationally Responsive Space (ORS). This paper leverages the knowledge gained from decades of experience with the semi-reusable NASA Space Shuttle to understand how the costs of a military next generation semi-reusable space transport might behave in the real world - and how it might be made as affordable as desired. The NASA Space Shuttle had a semi-expendable booster, that being the reusable Solid Rocket MotorslBoosters (SRMlSRB) and the expendable cryogenic External Tank (ET), with a reusable cargo and crew capable orbiter. This paper will explore DoD concepts that invert this architectural arrangement, using a reusable booster plane that flies back to base soon after launch, with the in-space elements of the launch system being the expendable portions. Cost estimating in the earliest stages of any potential, large scale program has limited usefulness. As a result, the emphasis here is on developing an approach, a structure, and the basic concepts that could continue to be matured as the program gains knowledge. Where cost estimates are provided, these results by necessity carry many caveats and assumptions, and this analysis becomes more about ways in which drivers of costs for diverse scenarios can be better understood. The paper is informed throughout with a design-for-cost philosophy whereby the design and technology features of the proposed RBS (who and what, the "architecture") are taken as linked at the hip to a desire to perform a certain mission (where and when), and together these inform the cost, responsiveness, performance and sustainability (how) of the system. Concepts for developing, acquiring, producing or operating the system will be shown for their inextricable relationship to the "architecture" of the system, and how these too relate to costs

Reliable, Reusable Cryotank, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Microcracking issues have significantly limited the reusability of state-of-the-art (SOA) composite cryotanks. While developers have made some progress addressing...

Application of CFRP with High Hydrogen Gas Barrier Characteristics to Fuel Tanks of Space Transportation System

Science.gov (United States)

Yonemoto, Koichi; Yamamoto, Yuta; Okuyama, Keiichi; Ebina, Takeo

In the future, carbon fiber reinforced plastics (CFRPs) with high hydrogen gas barrier performance will find wide applications in all industrial hydrogen tanks that aim at weight reduction; the use of such materials will be preferred to the use of conventional metallic materials such as stainless steel or aluminum. The hydrogen gas barrier performance of CFRP will become an important issue with the introduction of hydrogen-fuel aircraft. It will also play an important role in realizing fully reusable space transportation system that will have high specific tensile CFRP structures. Such materials are also required for the manufacture of high-pressure hydrogen gas vessels for use in the fuel cell systems of automobiles. This paper introduces a new composite concept that can be used to realize CFRPs with high hydrogen gas barrier performance for applications in the cryogenic tanks of fully reusable space transportation system by the incorporation of a nonmetallic crystal layer, which is actually a dense and highly oriented clay crystal laminate. The preliminary test results show that the hydrogen gas barrier characteristics of this material after cryogenic heat shocks and cyclic loads are still better than those of other polymer materials by approximately two orders of magnitude.

The European Space Agency's FESTIP initiative

Science.gov (United States)

Burleson, Daphne

1998-01-01

In an effort to reduce the cost of access and open up new markets, the European Space Agency has begun a program called Future European Space Transportation Investigations Programme or FESTIP, in which reusable launcher concepts are being studied and developed. The ideal reusable launcher would be comparable to a normal aircraft in that it would be capable of taking off from many possible locations on Earth, enter the desired orbital plane, then accelerate to orbital velocity, release its payload, de-orbit, disperse its kinetic energy and land at the take-off base to be prepared for its next flight following a quick turnaround time. This ideal vehicle would be called the `single-stage-to-orbit reusable rocket launcher' or SSTO-RRL. All space launchers currently in use are staged to orbit and expendable, except the US Space Shuttle, and there is no SSTO-RRL in operation as yet. This paper will discuss the design options being studied by the European Space Agency (ESA) as well as their practical use in serving the space-launch market (FESTIP Workshop 1).

Lessons learned from the development and manufacture of ceramic reusable surface insulation materials for the space shuttle orbiters

Science.gov (United States)

Banas, R. P.; Elgin, D. R.; Cordia, E. R.; Nickel, K. N.; Gzowski, E. R.; Aguiler, L.

1983-01-01

Three ceramic, reusable surface insulation materials and two borosilicate glass coatings were used in the fabrication of tiles for the Space Shuttle orbiters. Approximately 77,000 tiles were made from these materials for the first three orbiters, Columbia, Challenger, and Discovery. Lessons learned in the development, scale up to production and manufacturing phases of these materials will benefit future production of ceramic reusable surface insulation materials. Processing of raw materials into tile blanks and coating slurries; programming and machining of tiles using numerical controlled milling machines; preparing and spraying tiles with the two coatings; and controlling material shrinkage during the high temperature (2100-2275 F) coating glazing cycles are among the topics discussed.

Future Launch Vehicle Structures - Expendable and Reusable Elements

Science.gov (United States)

Obersteiner, M. H.; Borriello, G.

2002-01-01

Further evolution of existing expendable launch vehicles will be an obvious element influencing the future of space transportation. Besides this reusability might be the change with highest potential for essential improvement. The expected cost reduction and finally contributing to this, the improvement of reliability including safe mission abort capability are driving this idea. Although there are ideas of semi-reusable launch vehicles, typically two stages vehicles - reusable first stage or booster(s) and expendable second or upper stage - it should be kept in mind that the benefit of reusability will only overwhelm if there is a big enough share influencing the cost calculation. Today there is the understanding that additional technology preparation and verification will be necessary to master reusability and get enough benefits compared with existing launch vehicles. This understanding is based on several technology and system concepts preparation and verification programmes mainly done in the US but partially also in Europe and Japan. The major areas of necessary further activities are: - System concepts including business plan considerations - Sub-system or component technologies refinement - System design and operation know-how and capabilities - Verification and demonstration oriented towards future mission mastering: One of the most important aspects for the creation of those coming programmes and activities will be the iterative process of requirements definition derived from concepts analyses including economical considerations and the results achieved and verified within technology and verification programmes. It is the intention of this paper to provide major trends for those requirements focused on future launch vehicles structures. This will include the aspects of requirements only valid for reusable launch vehicles and those common for expendable, semi-reusable and reusable launch vehicles. Structures and materials is and will be one of the

Reusable Rack Interface Controller Common Software for Various Science Research Racks on the International Space Station

Science.gov (United States)

Lu, George C.

2003-01-01

The purpose of the EXPRESS (Expedite the PRocessing of Experiments to Space Station) rack project is to provide a set of predefined interfaces for scientific payloads which allow rapid integration into a payload rack on International Space Station (ISS). VxWorks' was selected as the operating system for the rack and payload resource controller, primarily based on the proliferation of VME (Versa Module Eurocard) products. These products provide needed flexibility for future hardware upgrades to meet everchanging science research rack configuration requirements. On the International Space Station, there are multiple science research rack configurations, including: 1) Human Research Facility (HRF); 2) EXPRESS ARIS (Active Rack Isolation System); 3) WORF (Window Observational Research Facility); and 4) HHR (Habitat Holding Rack). The RIC (Rack Interface Controller) connects payloads to the ISS bus architecture for data transfer between the payload and ground control. The RIC is a general purpose embedded computer which supports multiple communication protocols, including fiber optic communication buses, Ethernet buses, EIA-422, Mil-Std-1553 buses, SMPTE (Society Motion Picture Television Engineers)-170M video, and audio interfaces to payloads and the ISS. As a cost saving and software reliability strategy, the Boeing Payload Software Organization developed reusable common software where appropriate. These reusable modules included a set of low-level driver software interfaces to 1553B. RS232, RS422, Ethernet buses, HRDL (High Rate Data Link), video switch functionality, telemetry processing, and executive software hosted on the FUC computer. These drivers formed the basis for software development of the HRF, EXPRESS, EXPRESS ARIS, WORF, and HHR RIC executable modules. The reusable RIC common software has provided extensive benefits, including: 1) Significant reduction in development flow time; 2) Minimal rework and maintenance; 3) Improved reliability; and 4) Overall

A Status of the Advanced Space Transportation Program from Planning to Action

Science.gov (United States)

Lyles, Garry; Griner, Carolyn

1998-01-01

A Technology Plan for Enabling Commercial Space Business was presented at the 48th International Astronautical Congress in Turin, Italy. This paper presents a status of the program's accomplishments. Technology demonstrations have progressed in each of the four elements of the program; (1) Low Cost Technology, (2) Advanced Reusable Technology, (3) Space Transfer Technology and (4) Space Transportation Research. The Low Cost Technology program element is primarily focused at reducing development and acquisition costs of aerospace hardware using a "design to cost" philosophy with robust margins, adapting commercial manufacturing processes and commercial off-the-shelf hardware. The attributes of this philosophy for small payload launch are being demonstrated at the component, sub-system, and system level. The X-34 "Fastrac" engine has progressed through major component and subsystem demonstrations. A propulsion system test bed has been implemented for system-level demonstration of component and subsystem technologies; including propellant tankage and feedlines, controls, pressurization, and engine systems. Low cost turbopump designs, commercial valves and a controller are demonstrating the potential for a ten-fold reduction in engine and propulsion system costs. The Advanced Reusable Technology program element is focused on increasing life through high strength-to-weight structures and propulsion components, highly integrated propellant tanks, automated checkout and health management and increased propulsion system performance. The validation of rocket based combined cycle (RBCC) propulsion is pro,-,ressing through component and subsystem testing. RBCC propulsion has the potential to provide performance margin over an all rocket system that could result in lower gross liftoff weight, a lower propellant mass fraction or a higher payload mass fraction. The Space Transfer Technology element of the program is pursuing technology that can improve performance and

Operational Issues in the Development of a Cost-Effective Reusable LOX/LH2 Engine

Science.gov (United States)

Ballard, Richard O.

2003-01-01

The NASA Space Launch Initiative (SLI) was initiated in early 2001 to conduct technology development and to reduce the business and technical risk associated with developing the next-generation reusable launch system. In the field of main propulsion, two LOXLH2 rocket engine systems, the Pratt & Whitney / Aerojet Joint Venture (JV) COBRA and the Rocketdyne RS-83, were funded to develop a safe, economical, and reusable propulsion system. Given that a large-thrust reusable rocket engine program had not been started in the U.S. since 1971, with the Space Shuttle Main Engine (SSME), this provided an opportunity to build on the experience developed on the SSME system, while exploiting advances in technology that had occurred in the intervening 30 years. One facet of engine development that was identified as being especially vital in order to produce an optimal system was in the areas of operability and maintainability. In order to achieve the high levels of performance required by the Space Shuttle, the SSME system is highly complex with very tight tolerances and detailed requirements. Over the lifetime of the SSME program, the engine has required a high level of manpower to support the performance of inspections, maintenance (scheduled and unscheduled) and operations (prelaunch and post-flight). As a consequence, the labor- intensive needs of the SSME provide a significant impact to the overall cost efficiency of the Space Transportation System (STS). One of the strategic goals of the SLI is to reduce cost by requiring the engine(s) to be easier (Le. less expensive) to operate and maintain. The most effective means of accomplishing this goal is to infuse the operability and maintainability features into the engine design from the start. This paper discusses some of the operational issues relevant to a reusable LOx/LH2 main engine, and the means by which their impact is mitigated in the design phase.

Benefits of Government Incentives for Reusable Launch Vehicle Development

Science.gov (United States)

Shaw, Eric J.; Hamaker, Joseph W.; Prince, Frank A.

1998-01-01

Many exciting new opportunities in space, both government missions and business ventures, could be realized by a reduction in launch prices. Reusable launch vehicle (RLV) designs have the potential to lower launch costs dramatically from those of today's expendable and partially-expendable vehicles. Unfortunately, governments must budget to support existing launch capability, and so lack the resources necessary to completely fund development of new reusable systems. In addition, the new commercial space markets are too immature and uncertain to motivate the launch industry to undertake a project of this magnitude and risk. Low-cost launch vehicles will not be developed without a mature market to service; however, launch prices must be reduced in order for a commercial launch market to mature. This paper estimates and discusses the various benefits that may be reaped from government incentives for a commercial reusable launch vehicle program.

Space shuttle orbit maneuvering engine reusable thrust chamber program

Science.gov (United States)

Senneff, J. M.

1975-01-01

Reusable thrust chamber and injector concepts were evaluated for the space shuttle orbit maneuvering engine (OME). Parametric engine calculations were carried out by computer program for N2O4/amine, LOX/amine and LOX/hydrocarbon propellant combinations for engines incorporating regenerative cooled and insulated columbium thrust chambers. The calculation methods are described including the fuel vortex film cooling method of combustion gas temperature control, and performance prediction. A method of acceptance of a regeneratively cooled heat rejection reduction using a silicone oil additive was also demonstrated by heated tube heat transfer testing. Regeneratively cooled thrust chamber operation was also demonstrated where the injector was characterized for the OME application with a channel wall regenerative thrust chamber. Bomb stability testing of the demonstration chambers/injectors demonstrated recovery for the nominal design of acoustic cavities. Cavity geometry changes were also evaluated to assess their damping margin. Performance and combustion stability was demonstrated of the originally developed 10 inch diameter combustion pattern operating in an 8 inch diameter thrust chamber.

Specific Space Transportation Costs to GEO - Past, Present and Future

Science.gov (United States)

Koelle, Dietrich E.

2002-01-01

The largest share of space missions is going to the Geosynchronous Orbit (GEO); they have the highest commercial importance. The paper first shows the historic trend of specific transportation costs to GEO from 1963 to 2002. It started out with more than 500 000 /kg(2002-value) and has come down to 36 000 /kg. This reduction looks impressive, however, the reason is NOT improved technology or new techniques but solely the growth of GEO payloads`unit mass. The first GEO satellite in 1963 did have a mass of 36 kg mass (BoL) . This has grown to a weight of 1600 kg (average of all GEO satellites) in the year 2000. Mass in GEO after injection is used here instead of GTO mass since the GTO mass depends on the launch site latitude. The specific cost reduction is only due to the "law-of-scale", valid in the whole transportation business: the larger the payload, the lower the specific transportation cost. The paper shows the actual prices of launch services to GTO by the major launch vehicles. Finally the potential GEO transportation costs of future launch systems are evaluated. What is the potential reduction of specific transportation costs if reusable elements are introduced in future systems ? Examples show that cost reductions up to 75 % seem achievable - compared to actual costs - but only with launch systems optimized according to modern principles of cost engineering. 1. 53rd International Astronautical Congress, World Space Congress Houston 2. First Submission 3. Specific Space Transportation Costs to GEO - Past, Present and Future 4. KOELLE, D.E. 5. IAA.1.1 Launch Vehicles' Cost Engineering and Economic Competitiveness 6. D.E. Koelle; A.E. Goldstein 7. One overhead projector and screen 8. Word file attached 9. KOELLE I have approval to attend the Congress. I am not willing to present this paper at the IAC Public Outreach Program.

Risk Perception and Communication in Commercial Reusable Launch Vehicle Operations

Science.gov (United States)

Hardy, Terry L.

2005-12-01

A number of inventors and entrepreneurs are currently attempting to develop and commercially operate reusable launch vehicles to carry voluntary participants into space. The operation of these launch vehicles, however, produces safety risks to the crew, to the space flight participants, and to the uninvolved public. Risk communication therefore becomes increasingly important to assure that those involved in the flight understand the risk and that those who are not directly involved understand the personal impact of RLV operations on their lives. Those involved in the launch vehicle flight may perceive risk differently from those non-participants, and these differences in perception must be understood to effectively communicate this risk. This paper summarizes existing research in risk perception and communication and applies that research to commercial reusable launch vehicle operations. Risk communication is discussed in the context of requirements of United States law for informed consent from any space flight participants on reusable suborbital launch vehicles.

Reusable Agena study. Volume 2: Technical

Science.gov (United States)

Carter, W. K.; Piper, J. E.; Douglass, D. A.; Waller, E. W.; Hopkins, C. V.; Fitzgerald, E. T.; Sagawa, S. S.; Carter, S. A.; Jensen, H. L.

1974-01-01

The application of the existing Agena vehicle as a reusable upper stage for the space shuttle is discussed. The primary objective of the study is to define those changes to the Agena required for it to function in the reusable mode in the 100 percent capture of the NASA-DOD mission model. This 100 percent capture is achieved without use of kick motors or stages by simply increasing the Agena propellant load by using optional strap-on-tanks. The required shuttle support equipment, launch and flight operations techniques, development program, and cost package are also defined.

Space 2035: Technology, Transparency, and Trusted Immunity

Science.gov (United States)

2010-02-17

12 Figure 2: Maglev -Assisted RLV Concepts .................................................................................. 14...reusable launch vehicles (RLVs). 12, 13 14 Figure 2: Maglev -Assisted RLV Concepts 14 By 2035, several innovative concepts for space...transportation may emerge. These include magnetically-levitated and assisted ( maglev ) RLVs; a novel Space Pier concept, which comprises a series of

Reusable launch vehicle facts and fantasies

Science.gov (United States)

Kaplan, Marshall H.

2002-01-01

Many people refuse to address many of the realities of reusable launch vehicle systems, technologies, operations and economics. Basic principles of physics, space flight operations, and business limitations are applied to the creation of a practical vision of future expectations. While reusable launcher concepts have been proposed for several decades, serious review of potential designs began in the mid-1990s, when NASA decided that a Space Shuttle replacement had to be pursued. A great deal of excitement and interest was quickly generated by the prospect of ``orders-of-magnitude'' reduction in launch costs. The potential for a vastly expanded space program motivated the entire space community. By the late-1990s, and after over one billion dollars were spent on the technology development and privately-funded concepts, it had become clear that there would be no new, near-term operational reusable vehicle. Many factors contributed to a very expensive and disappointing effort to create a new generation of launch vehicles. It began with overly optimistic projections of technology advancements and the belief that a greatly increased demand for satellite launches would be realized early in the 21st century. Contractors contributed to the perception of quickly reachable technology and business goals, thus, accelerating the enthusiasm and helping to create a ``gold rush'' euphoria. Cost, schedule and performance margins were all highly optimistic. Several entrepreneurs launched start up companies to take advantage of the excitement and the availability of investor capital. Millions were raised from private investors and venture capitalists, based on little more than flashy presentations and animations. Well over $500 million were raised by little-known start up groups to create reusable systems, which might complete for the coming market in launch services. By 1999, it was clear that market projections, made just two years earlier, were not going to be realized. Investors

Economic Metrics for Commercial Reusable Space Transportation Systems

Science.gov (United States)

Shaw, Eric J.; Hamaker, Joseph (Technical Monitor)

2000-01-01

baseline. Still, economic metrics for technology development in these Programs and projects remain fairly straightforward, being based on reductions in acquisition and operating costs of the Systems. One of the most challenging requirements that NASA levies on its Programs is to plan for the commercialization of the developed technology. Some NASA Programs are created for the express purpose of developing technology for a particular industrial sector, such as aviation or space transportation, in financial partnership with that sector. With industrial investment, another set of goals, constraints and expectations are levied on the technology program. Economic benefit metrics then expand beyond cost and cost savings to include the marketability, profit, and investment return requirements of the private sector. Commercial investment criteria include low risk, potential for high return, and strategic alignment with existing product lines. These corporate criteria derive from top-level strategic plans and investment goals, which rank high among the most proprietary types of information in any business. As a result, top-level economic goals and objectives that industry partners bring to cooperative programs cannot usually be brought into technical processes, such as systems engineering, that are worked collaboratively between Industry and Government. In spite of these handicaps, the top-level economic goals and objectives of a joint technology program can be crafted in such a way that they accurately reflect the fiscal benefits from both Industry and Government perspectives. Valid economic metrics can then be designed that can track progress toward these goals and objectives, while maintaining the confidentiality necessary for the competitive process.

Using PHM to measure equipment usable life on the Air Force's next generation reusable space booster

Science.gov (United States)

Blasdel, A.

The U.S. Air Force procures many launch vehicles and launch vehicle services to place their satellites at their desired location in space. The equipment on-board these satellite and launch vehicle often suffer from premature failures that result in the total loss of the satellite or a shortened mission life sometimes requiring the purchase of a replacement satellite and launch vehicle. The Air Force uses its EELV to launch its high priority satellites. Due to a rise in the cost of purchasing a launch using the Air Force's EELV from 72M in 1997 to as high as 475M per launch today, the Air Force is working to replace the EELV with a reusable space booster (RSB). The RSB will be similar in design and operations to the recently cancelled NASA reusable space booster known as the Space Shuttle. If the Air Force uses the same process that procures the EELV and other launch vehicles and satellites, the RSB will also suffer from premature equipment failures thus putting the payloads at a similar high risk of mission failure. The RSB is expected to lower each launch cost by 50% compared to the EELV. The development of the RSB offers the Air Force an opportunity to use a new reliability paradigm that includes a prognostic and health management program and a condition-based maintenance program. These both require using intelligent, decision making self-prognostic equipment The prognostic and health management program and its condition-based maintenance program allows increases in RSB equipment usable life, lower logistics and maintenance costs, while increasing safety and mission assurance. The PHM removes many decisions from personnel that, in the past resulted in catastrophic failures and loss of life. Adding intelligent, decision-making self-prognostic equipment to the RSB will further decrease launch costs while decreasing risk and increasing safety and mission assurance.

Reusable Surface Insulation

Science.gov (United States)

1997-01-01

Advanced Flexible Reusable Surface Insulation, developed by Ames Research Center, protects the Space Shuttle from the searing heat that engulfs it on reentry into the Earth's atmosphere. Initially integrated into the Space Shuttle by Rockwell International, production was transferred to Hi-Temp Insulation Inc. in 1974. Over the years, Hi-Temp has created many new technologies to meet the requirements of the Space Shuttle program. This expertise is also used commercially, including insulation blankets to cover aircrafts parts, fire barrier material to protect aircraft engine cowlings and aircraft rescue fire fighter suits. A Fire Protection Division has also been established, offering the first suit designed exclusively by and for aircraft rescue fire fighters. Hi-Temp is a supplier to the Los Angeles City Fire Department as well as other major U.S. civil and military fire departments.

High-Payoff Space Transportation Design Approach with a Technology Integration Strategy

Science.gov (United States)

McCleskey, C. M.; Rhodes, R. E.; Chen, T.; Robinson, J.

2011-01-01

A general architectural design sequence is described to create a highly efficient, operable, and supportable design that achieves an affordable, repeatable, and sustainable transportation function. The paper covers the following aspects of this approach in more detail: (1) vehicle architectural concept considerations (including important strategies for greater reusability); (2) vehicle element propulsion system packaging considerations; (3) vehicle element functional definition; (4) external ground servicing and access considerations; and, (5) simplified guidance, navigation, flight control and avionics communications considerations. Additionally, a technology integration strategy is forwarded that includes: (a) ground and flight test prior to production commitments; (b) parallel stage propellant storage, such as concentric-nested tanks; (c) high thrust, LOX-rich, LOX-cooled first stage earth-to-orbit main engine; (d) non-toxic, day-of-launch-loaded propellants for upper stages and in-space propulsion; (e) electric propulsion and aero stage control.

Low-cost management aspects for developing, producing and operating future space transportation systems

Science.gov (United States)

Goehlich, Robert A.; Rücker, Udo

2005-01-01

It is believed that a potential means for further significant reduction of the recurrent launch cost, which results also in a stimulation of launch rates of small satellites, is to make the launcher reusable, to increase its reliability and to make it suitable for new markets such as mass space tourism. Therefore, not only launching small satellites with expendable rockets on non-regular flights but also with reusable rockets on regular flights should be considered for the long term. However, developing, producing and operating reusable rockets require a fundamental change in the current "business as usual" philosophy. Under current conditions, it might not be possible to develop, to produce or to operate a reusable vehicle fleet economically. The favorite philosophy is based on "smart business" processes adapted by the authors using cost engineering techniques. In the following paper, major strategies for reducing costs are discussed, which are applied for a representative program proposal.

Sustaining Human Presence on Mars Using ISRU and a Reusable Lander

Science.gov (United States)

Arney, Dale C.; Jones, Christopher A.; Klovstad, Jordan J.; Komar, D.R.; Earle, Kevin; Moses, Robert; Shyface, Hilary R.

2015-01-01

This paper presents an analysis of the impact of ISRU (In-Site Resource Utilization), reusability, and automation on sustaining a human presence on Mars, requiring a transition from Earth dependence to Earth independence. The study analyzes the surface and transportation architectures and compared campaigns that revealed the importance of ISRU and reusability. A reusable Mars lander, Hercules, eliminates the need to deliver a new descent and ascent stage with each cargo and crew delivery to Mars, reducing the mass delivered from Earth. As part of an evolvable transportation architecture, this investment is key to enabling continuous human presence on Mars. The extensive use of ISRU reduces the logistics supply chain from Earth in order to support population growth at Mars. Reliable and autonomous systems, in conjunction with robotics, are required to enable ISRU architectures as systems must operate and maintain themselves while the crew is not present. A comparison of Mars campaigns is presented to show the impact of adding these investments and their ability to contribute to sustaining a human presence on Mars.

Development of a novel controllable, multidirectional, reusable metallic port with a wide working space.

Science.gov (United States)

Hosaka, Seiji; Ohdaira, Takeshi; Umemoto, Satoshi; Hashizume, Makoto; Kawamoto, Shunji

2013-12-01

Endoscopic surgery is currently a standard procedure in many countries. Furthermore, conventional four-port laparoscopic cholecystectomy is developing into a single-port procedure. However, in many developing countries, disposable medical products are expensive and adequate medical waste disposable facilities are absent. Advanced medical treatments such as laparoscopic or single-port surgeries are not readily available in many areas of developing countries, and there are often no other sterilization methods besides autoclaving. Moreover, existing reusable metallic ports are impractical and are thus not widely used. We developed a novel controllable, multidirectional single-port device that can be autoclaved, and with a wide working space, which was employed in five patients. In all patients, laparoscopic cholecystectomy was accomplished without complications. Our device facilitates single-port surgery in areas of the world with limited sterilization methods and offers a novel alternative to conventional tools for creating a smaller incision, decrease postoperative pain, and improve cosmesis. This novel device can also lower the cost of medical treatment and offers a promising tool for major surgeries requiring a wide working space.

A study of upwind schemes on the laminar hypersonic heating predictions for the reusable space vehicle

Science.gov (United States)

Qu, Feng; Sun, Di; Zuo, Guang

2018-06-01

With the rapid development of the Computational Fluid Dynamics (CFD), Accurate computing hypersonic heating is in a high demand for the design of the new generation reusable space vehicle to conduct deep space exploration. In the past years, most researchers try to solve this problem by concentrating on the choice of the upwind schemes or the definition of the cell Reynolds number. However, the cell Reynolds number dependencies and limiter dependencies of the upwind schemes, which are of great importance to their performances in hypersonic heating computations, are concerned by few people. In this paper, we conduct a systematic study on these properties respectively. Results in our test cases show that SLAU (Simple Low-dissipation AUSM-family) is with a much higher level of accuracy and robustness in hypersonic heating predictions. Also, it performs much better in terms of the limiter dependency and the cell Reynolds number dependency.

Design, Fabrication, and Initial Operation of a Reusable Irradiation Facility

International Nuclear Information System (INIS)

Heatherly, D.W.; Thoms, K.R.; Siman-Tov, I.I.; Hurst, M.T.

1999-01-01

A Heavy-Section Steel Irradiation (HSSI) Program project, funded by the US Nuclear Regulatory Commission, was initiated at Oak Ridge National Laboratory to develop reusable materials irradiation facilities in which metallurgical specimens of reactor pressure vessel steels could be irradiated. As a consequence, two new, identical, reusable materials irradiation facilities have been designed, fabricated, installed, and are now operating at the Ford Nuclear Reactor at the University of Michigan. The facilities are referred to as the HSSI-IAR facilities with the individual facilities being designated as IAR-1 and IAR-2. This new and unique facility design requires no cutting or grinding operations to retrieve irradiated specimens, all capsule hardware is totally reusable, and materials transported from site to site are limited to specimens only. At the time of this letter report, the facilities have operated successfully for approximately 2500 effective full-power hours

A Modular, Reusable Latch and Decking System for Securing Payloads During Launch and Planetary Surface Transport

Science.gov (United States)

Doggett, William R.; Dorsey, John T.; Jones, Thomas C.; King, Bruce D.; Mikulas, Martin M.

2011-01-01

Efficient handling of payloads destined for a planetary surface, such as the moon or mars, requires robust systems to secure the payloads during transport on the ground, in space and on the planetary surface. In addition, mechanisms to release the payloads need to be reliable to ensure successful transfer from one vehicle to another. An efficient payload handling strategy must also consider the devices available to support payload handling. Cranes used for overhead lifting are common to all phases of payload handling on Earth. Similarly, both recent and past studies have demonstrated that devices with comparable functionality will be needed to support lunar outpost operations. A first generation test-bed of a new high performance device that provides the capabilities of both a crane and a robotic manipulator, the Lunar Surface Manipulation System (LSMS), has been designed, built and field tested and is available for use in evaluating a system to secure payloads to transportation vehicles. A payload handling approach must address all phases of payload management including: ground transportation, launch, planetary transfer and installation in the final system. In addition, storage may be required during any phase of operations. Each of these phases requires the payload to be lifted and secured to a vehicle, transported, released and lifted in preparation for the next transportation or storage phase. A critical component of a successful payload handling approach is a latch and associated carrier system. The latch and carrier system should minimize requirements on the: payload, carrier support structure and payload handling devices as well as be able to accommodate a wide range of payload sizes. In addition, the latch should; be small and lightweight, support a method to apply preload, be reusable, integrate into a minimal set of hard-points and have manual interfaces to actuate the latch should a problem occur. A latching system which meets these requirements has been

A Concept of Two-Stage-To-Orbit Reusable Launch Vehicle

Science.gov (United States)

Yang, Yong; Wang, Xiaojun; Tang, Yihua

2002-01-01

Reusable Launch Vehicle (RLV) has a capability of delivering a wide rang of payload to earth orbit with greater reliability, lower cost, more flexibility and operability than any of today's launch vehicles. It is the goal of future space transportation systems. Past experience on single stage to orbit (SSTO) RLVs, such as NASA's NASP project, which aims at developing an rocket-based combined-cycle (RBCC) airplane and X-33, which aims at developing a rocket RLV, indicates that SSTO RLV can not be realized in the next few years based on the state-of-the-art technologies. This paper presents a concept of all rocket two-stage-to-orbit (TSTO) reusable launch vehicle. The TSTO RLV comprises an orbiter and a booster stage. The orbiter is mounted on the top of the booster stage. The TSTO RLV takes off vertically. At the altitude about 50km the booster stage is separated from the orbiter, returns and lands by parachutes and airbags, or lands horizontally by means of its own propulsion system. The orbiter continues its ascent flight and delivers the payload into LEO orbit. After completing orbit mission, the orbiter will reenter into the atmosphere, automatically fly to the ground base and finally horizontally land on the runway. TSTO RLV has less technology difficulties and risk than SSTO, and maybe the practical approach to the RLV in the near future.

Economic Analysis of a Postulated space Tourism Transportation System

Science.gov (United States)

Hill, Allan S.

2002-01-01

Design concepts and associated costs were defined for a family of launch vehicles supporting a space tourism endeavor requiring the weekly transport of space tourists to and from an Earth- orbiting facility. The stated business goal for the Space Tourist Transportation System (STTS) element of the proposed commercial space venture was to transport and return ~50 passengers a week to LEO at a cost of roughly 50 K per seat commencing in 2005. This paper summarizes the economic analyses conducted within a broader Systems Engineering study of the postulated concept. Parametric costs were derived using TransCostSystems' (TCS) Cost Engineering Handbook, version 7. Costs were developed as a function of critical system characteristics and selected business scenarios. Various economic strategies directed toward achieving a cost of ~50 K per seat were identified and examined. The study indicated that with a `nominal' business scenario, the initial cost for developing and producing a fully reusable, 2-stage STTS element for a baseline of 46-passengers was about 15.5 B assuming a plausible `commercialization factor' of 0.333. The associated per-seat ticket cost was ~890 K, more than an order of magnitude higher than desired. If the system is enlarged to 104 passengers for better efficiency, the STTS initial cost for the nominal business scenario is increased to about 19.8 B and the per-seat ticket cost is reduced to ~530 K. It was concluded that achieving the desired ticket cost of 50 K per seat is not feasible unless the size of the STTS, and therefore of the entire system, is substantially increased. However, for the specified operational characteristics, it was shown that a system capacity of thousands of passengers per week is required. This implies an extremely high total system development cost, which is not very realistic as a commercial venture, especially in the proposed time frame. These results suggested that ambitious commercial space ventures may have to rely on

REUSABLE PROPULSION ARCHITECTURE FOR SUSTAINABLE LOW-COST ACCESS TO SPACE

Science.gov (United States)

Bonometti, Joseph; Frame, Kyle L.; Dankanich, John W.

2005-01-01

Two transportation architecture changes are presented at either end of a conventional two-stage rocket flight: 1) Air launch using a large, conventional, pod hauler design (i.e., Crossbow)ans 2) Momentum exchange tether (i.e., an in-space asset like MXER). Air launch has ana analytically justified cost reduction of approx. 10%, but its intangible benefits suggest real-world operations cost reductions much higher: 1) Inherent launch safety; 2) Mission Risk Reduction; 3) Favorable payload/rocket limitations; and 4) Leveraging the aircraft for other uses (military transport, commercial cargo, public outreach activities, etc.)

Comparative life cycle assessment of disposable and reusable laryngeal mask airways.

Science.gov (United States)

Eckelman, Matthew; Mosher, Margo; Gonzalez, Andres; Sherman, Jodi

2012-05-01

Growing awareness of the negative impacts from the practice of health care on the environment and public health calls for the routine inclusion of life cycle criteria into the decision-making process of device selection. Here we present a life cycle assessment of 2 laryngeal mask airways (LMAs), a one-time-use disposable Unique™ LMA and a 40-time-use reusable Classic™ LMA. In life cycle assessment, the basis of comparison is called the "functional unit." For this report, the functional unit of the disposable and reusable LMAs was taken to be maintenance of airway patency by 40 disposable LMAs or 40 uses of 1 reusable LMA. This was a cradle-to-grave study that included inputs and outputs for the manufacture, transport, use, and waste phases of the LMAs. The environmental impacts of the 2 LMAs were estimated using SimaPro life cycle assessment software and the Building for Environmental and Economic Sustainability impact assessment method. Sensitivity and simple life cycle cost analyses were conducted to aid in interpretation of the results. The reusable LMA was found to have a more favorable environmental profile than the disposable LMA as used at Yale New Haven Hospital. The most important sources of impacts for the disposable LMA were the production of polymers, packaging, and waste management, whereas for the reusable LMA, washing and sterilization dominated for most impact categories. The differences in environmental impacts between these devices strongly favor reusable devices. These benefits must be weighed against concerns regarding transmission of infection. Health care facilities can decrease their environmental impacts by using reusable LMAs, to a lesser extent by selecting disposable LMA models that are not made of certain plastics, and by ordering in bulk from local distributors. Certain practices would further reduce the environmental impacts of reusable LMAs, such as increasing the number of devices autoclaved in a single cycle to 10 (-25% GHG

Macroeconomic Benefits of Low-Cost Reusable Launch Vehicles

Science.gov (United States)

Shaw, Eric J.; Greenberg, Joel

1998-01-01

The National Aeronautics and Space Administration (NASA) initiated its Reusable Launch Vehicle (RLV) Technology Program to provide information on the technical and commercial feasibility of single-stage to orbit (SSTO), fully-reusable launchers. Because RLVs would not depend on expendable hardware to achieve orbit, they could take better advantage of economies of scale than expendable launch vehicles (ELVs) that discard costly hardware on ascent. The X-33 experimental vehicle, a sub-orbital, 60%-scale prototype of Lockheed Martin's VentureStar SSTO RLV concept, is being built by Skunk Works for a 1999 first flight. If RLVs achieve prices to low-earth orbit of less than $1000 US per pound, they could hold promise for eliciting an elastic response from the launch services market. As opposed to the capture of existing market, this elastic market would represent new space-based industry businesses. These new opportunities would be created from the next tier of business concepts, such as space manufacturing and satellite servicing, that cannot earn a profit at today's launch prices but could when enabled by lower launch costs. New business creation contributes benefits to the US Government (USG) and the US economy through increases in tax revenues and employment. Assumptions about the costs and revenues of these new ventures, based on existing space-based and aeronautics sector businesses, can be used to estimate the macroeconomic benefits provided by new businesses. This paper examines these benefits and the flight prices and rates that may be required to enable these new space industries.

Weight Analysis of Two-Stage-To-Orbit Reusable Launch Vehicles for Military Applications

National Research Council Canada - National Science Library

Caldwell, Richard A

2005-01-01

In response to Department of Defense (DoD) requirements for responsive and low-cost space access, this design study provides an objective empty weight analysis of potential reusable launch vehicle (RLV) configurations...

A Reusable, Oxidizer-Cooled, Hybrid Aerospike Rocket Motor for Flight Test, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — The proposed innovation is to use the refrigerant capabilities of nitrous oxide (N2O) to provide the cooling required for reusable operation of an aerospike nozzle...

Reusable Launch Vehicle Technology Program

Science.gov (United States)

Freeman, Delma C., Jr.; Talay, Theodore A.; Austin, R. Eugene

1997-01-01

Industry/NASA reusable launch vehicle (RLV) technology program efforts are underway to design, test, and develop technologies and concepts for viable commercial launch systems that also satisfy national needs at acceptable recurring costs. Significant progress has been made in understanding the technical challenges of fully reusable launch systems and the accompanying management and operational approaches for achieving a low cost program. This paper reviews the current status of the RLV technology program including the DC-XA, X-33 and X-34 flight systems and associated technology programs. It addresses the specific technologies being tested that address the technical and operability challenges of reusable launch systems including reusable cryogenic propellant tanks, composite structures, thermal protection systems, improved propulsion and subsystem operability enhancements. The recently concluded DC-XA test program demonstrated some of these technologies in ground and flight test. Contracts were awarded recently for both the X-33 and X-34 flight demonstrator systems. The Orbital Sciences Corporation X-34 flight test vehicle will demonstrate an air-launched reusable vehicle capable of flight to speeds of Mach 8. The Lockheed-Martin X-33 flight test vehicle will expand the test envelope for critical technologies to flight speeds of Mach 15. A propulsion program to test the X-33 linear aerospike rocket engine using a NASA SR-71 high speed aircraft as a test bed is also discussed. The paper also describes the management and operational approaches that address the challenge of new cost effective, reusable launch vehicle systems.

Fuels and Space Propellants for Reusable Launch Vehicles: A Small Business Innovation Research Topic and Its Commercial Vision

Science.gov (United States)

Palaszewski, Bryan A.

1997-01-01

Under its Small Business Innovation Research (SBIR) program (and with NASA Headquarters support), the NASA Lewis Research Center has initiated a topic entitled "Fuels and Space Propellants for Reusable Launch Vehicles." The aim of this project would be to assist in demonstrating and then commercializing new rocket propellants that are safer and more environmentally sound and that make space operations easier. Soon it will be possible to commercialize many new propellants and their related component technologies because of the large investments being made throughout the Government in rocket propellants and the technologies for using them. This article discusses the commercial vision for these fuels and propellants, the potential for these propellants to reduce space access costs, the options for commercial development, and the benefits to nonaerospace industries. This SBIR topic is designed to foster the development of propellants that provide improved safety, less environmental impact, higher density, higher I(sub sp), and simpler vehicle operations. In the development of aeronautics and space technology, there have been limits to vehicle performance imposed by traditionally used propellants and fuels. Increases in performance are possible with either increased propellant specific impulse, increased density, or both. Flight system safety will also be increased by the use of denser, more viscous propellants and fuels.

Conceptual Design of an APT Reusable Spaceplane

Science.gov (United States)

Corpino, S.; Viola, N.

This paper concerns the conceptual design of an Aerial Propellant Transfer reusable spaceplane carried out during our PhD course under the supervision of prof. Chiesa. The new conceptual design methodology employed in order to develop the APT concept and the main characteristics of the spaceplane itself will be presented and discussed. The methodology for conceptual design has been worked out during the last three years. It was originally thought for atmospheric vehicle design but, thanks to its modular structure which makes it very flexible, it has been possible to convert it to space transportation systems design by adding and/or modifying a few modules. One of the major improvements has been for example the conception and development of the mission simulation and trajectory optimisation module. The methodology includes as main characteristics and innovations the latest techniques of geometric modelling and logistic, operational and cost aspects since the first stages of the project. Computer aided design techniques are used to obtain a better definition of the product at the end of the conceptual design phase and virtual reality concepts are employed to visualise three-dimensional installation and operational aspects, at least in part replacing full-scale mock- ups. The introduction of parametric three-dimensional CAD software integrated into the conceptual design methodology represents a great improvement because it allows to carry out different layouts and to assess them immediately. It is also possible to link the CAD system to a digital prototyping software which combines 3D visualisation and assembly analysis, useful to define the so-called Digital Mock-Up at Conceptual Level (DMUCL) which studies the integration between the on board systems, sized with simulation algorithms, and the airframe. DMUCL represents a very good means to integrate the conceptual design with a methodology turned towards dealing with Reliability, Availability, Maintainability and

Lunar transportation system

Science.gov (United States)

1993-07-01

The University Space Research Association (USRA) requested the University of Minnesota Spacecraft Design Team to design a lunar transportation infrastructure. This task was a year long design effort culminating in a complete conceptual design and presentation at Johnson Space Center. The mission objective of the design group was to design a system of vehicles to bring a habitation module, cargo, and crew to the lunar surface from LEO and return either or both crew and cargo safely to LEO while emphasizing component commonality, reusability, and cost effectiveness. During the course of the design, the lunar transportation system (LTS) has taken on many forms. The final design of the system is composed of two vehicles, a lunar transfer vehicle (LTV) and a lunar excursion vehicle (LEV). The LTV serves as an efficient orbital transfer vehicle between the earth and the moon while the LEV carries crew and cargo to the lunar surface. Presented in the report are the mission analysis, systems layout, orbital mechanics, propulsion systems, structural and thermal analysis, and crew systems, avionics, and power systems for this lunar transportation concept.

Reusable Boosters in a European-Russian Perspective

Science.gov (United States)

Deneu, François; Ramiandrasoa, Fabienne

2002-01-01

In 2001, EADS and Khrunichev SRPSC have initiated and carried out a working group devoted to the analysis of potential common studies and developments in the field of space activities. This working group came up with several propositions of interest, among which, the use of reusable boosters issued from Khrunichev previous design appeared to be promising when applied to heavy type launchers. Although the results required to be confirmed by detailed studies prior to final conclusions, preliminary studies have shown the interest of Ariane 5 configurations using such reusable booster in view of reducing the specific and launch cost as well as potentially increasing the performance. In November 2001, EADS and KHRUNICHEV SRPSC have started a study on an Ariane 5 plus reusable boosters configuration. This study aims at obtaining a better understanding of the advantages and drawbacks attached to such a use. Technical feasibility is more in depth analysed, with all recurring and not recurring aspects (including launch infrastructure modifications). Programmatic aspects are also addressed in order to better assess potential economic advantages and unavoidable drawbacks. Beyond that the identification of what could be, for western Europe and Russian players, an efficient and pay- off industrial organisation, is also a study theme of importance. This papers intends to present the main results achieved within this study and the propositions for the future which are likely to provide western Europe and Russia with stronger positions in the competitive field of launch business.

Real-Time Inhibitor Recession Measurements in the Space Shuttle Reusable Solid Rocket Motors

Science.gov (United States)

McWhorter, Bruce B.; Ewing, Mark E.; McCool, Alex (Technical Monitor)

2001-01-01

Real-time char line recession measurements were made on propellant inhibitors of the Space Shuttle Reusable Solid Rocket Motor (RSRM). The RSRM FSM-8 static test motor propellant inhibitors (composed of a rubber insulation material) were successfully instrumented with eroding potentiometers and thermocouples. The data was used to establish inhibitor recession versus time relationships. Normally, pre-fire and post-fire insulation thickness measurements establish the thermal performance of an ablating insulation material. However, post-fire inhibitor decomposition and recession measurements are complicated by the fact that most of the inhibitor is back during motor operation. It is therefore a difficult task to evaluate the thermal protection offered by the inhibitor material. Real-time measurements would help this task. The instrumentation program for this static test motor marks the first time that real-time inhibitors. This report presents that data for the center and aft field joint forward facing inhibitors. The data was primarily used to measure char line recession of the forward face of the inhibitors which provides inhibitor thickness reduction versus time data. The data was also used to estimate the inhibitor height versus time relationship during motor operation.

75 FR 70347 - Commercial Space Transportation Advisory Committee; Renewal

Science.gov (United States)

2010-11-17

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation... Regulations, notice is hereby given that the Commercial Space Transportation Advisory Committee (COMSTAC) has... matters concerning the U.S. commercial space transportation industry. The [[Page 70348

Reusable Xerogel Containing Quantum Dots with High Fluorescence Retention

Directory of Open Access Journals (Sweden)

Xiang-Yong Liang

2018-03-01

Full Text Available Although various analytical methods have been established based on quantum dots (QDs, most were conducted in solution, which is inadequate for storage/transportation and rapid analysis. Moreover, the potential environmental problems caused by abandoned QDs cannot be ignored. In this paper, a reusable xerogel containing CdTe with strong emission is established by introducing host–guest interactions between QDs and polymer matrix. This xerogel shows high QDs loading capacity without decrease or redshift in fluorescence (the maximum of loading is 50 wt % of the final xerogel, which benefits from the steric hindrance of β-cyclodextrin (βCD molecules. Host–guest interactions immobilize QDs firmly, resulting in the excellent fluorescence retention of the xerogel. The good detecting performance and reusability mean this xerogel could be employed as a versatile analysis platform (for quantitative and qualitative analyses. In addition, the xerogel can be self-healed by the aid of water.

Reusable tamper-indicating security seal

International Nuclear Information System (INIS)

Ryan, M.J.

1981-01-01

A reusable tamper-indicating mechanical security seal for use in safeguarding nuclear material has been developed. The high-security seal displays an unpredictable, randomly selected, five-digit code each time it is used. This five digit code serves the same purpose that the serial number does for conventional non-reusable seals - a unique identifier for each use or application. The newly developed reusable seal is completely enclosed within a seamless, tamper-indicating, plastic jacket. The jacket is designed to reveal any attempts to penetrate, section or to chemically remove and replace with a counterfeit for surreptitious purposes

Real-Time Inhibitor Recession Measurements in Two Space Shuttle Reusable Solid Rocket Motors

Science.gov (United States)

McWhorter, B. B.; Ewing, M. E.; Bolton, D. E.; Albrechtsen, K. U.; Earnest, T. E.; Noble, T. C.; Longaker, M.

2003-01-01

Real-time internal motor insulation char line recession measurements have been evaluated for two full-scale static tests of the Space Shuttle Reusable Solid Rocket Motor (RSRM). These char line recession measurements were recorded on the forward facing propellant grain inhibitors to better understand the thermal performance of these inhibitors. The RSRM propellant grain inhibitors are designed to erode away during motor operation, thus making it difficult to use post-fire observations to determine inhibitor thermal performance. Therefore, this new internal motor instrumentation is invaluable in establishing an accurate understanding of inhibitor recession versus motor operation time. The data for the first test was presented at the 37th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (AIAA 2001-3280) in July 2001. Since that time, a second full scale static test has delivered additional real-time data on inhibitor thermal performance. The evaluation of this data is presented in this paper. The second static test, in contrast to the first test, used a slightly different arrangement of instrumentation in the inhibitors. This instrumentation has yielded a better understanding of the inhibitor time dependent inboard tip recession. Graphs of inhibitor recession profiles with time are presented. Inhibitor thermal ablation models have been created from theoretical principals. The model predictions compare favorably with data from both tests. This verified modeling effort is important to support new inhibitor designs for a five segment Space Shuttle solid rocket motor. The internal instrumentation project on RSRM static tests is providing unique opportunities for other real-time internal motor measurements that could not otherwise be directly quantified.

Resonance controlled transport in phase space

Science.gov (United States)

Leoncini, Xavier; Vasiliev, Alexei; Artemyev, Anton

2018-02-01

We consider the mechanism of controlling particle transport in phase space by means of resonances in an adiabatic setting. Using a model problem describing nonlinear wave-particle interaction, we show that captures into resonances can be used to control transport in momentum space as well as in physical space. We design the model system to provide creation of a narrow peak in the distribution function, thus producing effective cooling of a sub-ensemble of the particles.

SpaceX's Dragon America's next generation spacecraft

CERN Document Server

Seedhouse, Erik

2016-01-01

This book describes Dragon V2, a futuristic vehicle that not only provides a means for NASA to transport its astronauts to the orbiting outpost but also advances SpaceX’s core objective of reusability. A direct descendant of Dragon, Dragon V2 can be retrieved, refurbished and re-launched. It is a spacecraft with the potential to completely revolutionize the economics of an industry where equipment costing hundreds of millions of dollars is routinely discarded after a single use. It was presented by SpaceX CEO Elon Musk in May 2014 as the spaceship that will carry NASA astronauts to the International Space Station as soon as 2016 SpaceX’s Dragon – America’s Next Generation Spacecraft describes the extraordinary feats of engineering and human achievement that have placed this revolutionary spacecraft at the forefront of the launch industry and positioned it as the precursor for ultimately transporting humans to Mars. It describes the design and development of Dragon, provides mission highlights of the f...

14 CFR 401.1 - The Office of Commercial Space Transportation.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false The Office of Commercial Space Transportation. 401.1 Section 401.1 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION GENERAL ORGANIZATION AND DEFINITIONS § 401.1 The Office of Commercial Space Transportation. The Office of...

Strategic Technologies for Deep Space Transport

Science.gov (United States)

Litchford, Ronald J.

2016-01-01

Deep space transportation capability for science and exploration is fundamentally limited by available propulsion technologies. Traditional chemical systems are performance plateaued and require enormous Initial Mass in Low Earth Orbit (IMLEO) whereas solar electric propulsion systems are power limited and unable to execute rapid transits. Nuclear based propulsion and alternative energetic methods, on the other hand, represent potential avenues, perhaps the only viable avenues, to high specific power space transport evincing reduced trip time, reduced IMLEO, and expanded deep space reach. Here, key deep space transport mission capability objectives are reviewed in relation to STMD technology portfolio needs, and the advanced propulsion technology solution landscape is examined including open questions, technical challenges, and developmental prospects. Options for potential future investment across the full compliment of STMD programs are presented based on an informed awareness of complimentary activities in industry, academia, OGAs, and NASA mission directorates.

Airframe Integration Trade Studies for a Reusable Launch Vehicle

Science.gov (United States)

Dorsey, John T.; Wu, Chauncey; Rivers, Kevin; Martin, Carl; Smith, Russell

1999-01-01

Future launch vehicles must be lightweight, fully reusable and easily maintained if low-cost access to space is to be achieved. The goal of achieving an economically viable Single-Stage-to-Orbit (SSTO) Reusable Launch Vehicle (RLV) is not easily achieved and success will depend to a large extent on having an integrated and optimized total system. A series of trade studies were performed to meet three objectives. First, to provide structural weights and parametric weight equations as inputs to configuration-level trade studies. Second, to identify, assess and quantify major weight drivers for the RLV airframe. Third, using information on major weight drivers, and considering the RLV as an integrated thermal structure (composed of thrust structures, tanks, thermal protection system, insulation and control surfaces), identify and assess new and innovative approaches or concepts that have the potential for either reducing airframe weight, improving operability, and/or reducing cost.

76 FR 42160 - Commercial Space Transportation Advisory Committee-Public Teleconference

Science.gov (United States)

2011-07-18

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee--Public Teleconference AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Space Transportation Operations Working Group of the Commercial Space Transportation Advisory...

Power unit-cargo space link in transport

Directory of Open Access Journals (Sweden)

Radmilović Zoran R.

2005-01-01

Full Text Available This paper deals with transportation technology regarding links between power unit and cargo space. These links can be divided into two groups: rigid and flexible. Rigid link, established between power unit and cargo space, is dominant in maritime and road transport (sea ships and trucks, and occasionally in transport on inland waterways (self- propelled barges. Flexible link is used in the railroad transport (systems with trailers and semi trailers, and in inland waterway transport (push - towing and pulling systems, and combinations of the systems. The main goal of this research is determination of possible link types and organization of the means of transportation.

76 FR 621 - Commercial Space Transportation Advisory Committee-Public Teleconference

Science.gov (United States)

2011-01-05

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation...: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section... given of a teleconference of the Commercial Space Transportation Advisory Committee (COMSTAC). The...

76 FR 41323 - Commercial Space Transportation Advisory Committee-Public Teleconference

Science.gov (United States)

2011-07-13

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation...: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section... given of a teleconference of the Commercial Space Transportation Advisory Committee (COMSTAC). The...

76 FR 4988 - Commercial Space Transportation Advisory Committee-Public Teleconference

Science.gov (United States)

2011-01-27

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation...: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section... given of a teleconference of the Commercial Space Transportation Advisory Committee (COMSTAC). The...

76 FR 78329 - Commercial Space Transportation Advisory Committee; Public Teleconference

Science.gov (United States)

2011-12-16

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation...: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section... given of a teleconference of the Commercial Space Transportation Advisory Committee (COMSTAC). The...

77 FR 44707 - Commercial Space Transportation Advisory Committee-Public Teleconference

Science.gov (United States)

2012-07-30

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation...: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section... given of three teleconferences of the Systems Working Group of the Commercial Space Transportation...

76 FR 4412 - Commercial Space Transportation Advisory Committee-Closed Session

Science.gov (United States)

2011-01-25

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation... Commercial Space Transportation Advisory Committee Special Closed Session. SUMMARY: Pursuant to Section 10(a... Commercial Space Transportation Advisory Committee (COMSTAC). The special closed session will be an...

78 FR 70093 - Commercial Space Transportation Advisory Committee-Closed Session

Science.gov (United States)

2013-11-22

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation... Commercial Space Transportation Advisory Committee Special Closed Session. SUMMARY: Pursuant to Section 10(a...), notice is hereby given of a special closed session of the Commercial Space Transportation Advisory...

76 FR 17474 - Commercial Space Transportation Advisory Committee-Open Meeting

Science.gov (United States)

2011-03-29

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation... Commercial Space Transportation Advisory Committee Open Meeting. SUMMARY: Pursuant to Section 10(a)(2) of the... the Commercial Space Transportation Advisory Committee (COMSTAC). The meeting will take place on...

77 FR 16891 - Commercial Space Transportation Advisory Committee-Open Meeting

Science.gov (United States)

2012-03-22

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation... Commercial Space Transportation Advisory Committee Open Meeting. SUMMARY: Pursuant to Section 10(a)(2) of the... the Commercial Space Transportation Advisory Committee (COMSTAC). The meeting will take place on...

78 FR 53496 - Commercial Space Transportation Advisory Committee; Open Meeting

Science.gov (United States)

2013-08-29

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation... Commercial Space Transportation Advisory Committee Open Meeting. SUMMARY: Pursuant to Section 10(a)(2) of the... the Commercial Space Transportation Advisory Committee (COMSTAC). The meeting will take place on...

76 FR 51461 - Commercial Space Transportation Advisory Committee-Open Meeting

Science.gov (United States)

2011-08-18

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation... Commercial Space Transportation Advisory Committee open meeting. SUMMARY: Pursuant to Section 10(a)(2) of the... the Commercial Space Transportation Advisory Committee (COMSTAC). The meeting will take place on...

78 FR 69742 - Commercial Space Transportation Advisory Committee-Open Meeting

Science.gov (United States)

2013-11-20

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation... Commercial Space Transportation Advisory Committee Open Meeting. SUMMARY: Pursuant to Section 10(a)(2) of the... the Commercial Space Transportation Advisory Committee (COMSTAC). The meeting will take place on...

77 FR 52108 - Commercial Space Transportation Advisory Committee; Open Meeting

Science.gov (United States)

2012-08-28

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation... Commercial Space Transportation Advisory Committee Open Meeting. SUMMARY: Pursuant to Section 10(a)(2) of the... the Commercial Space Transportation Advisory Committee (COMSTAC). The meeting will take place on...

75 FR 54002 - Commercial Space Transportation Advisory Committee-Open Meeting

Science.gov (United States)

2010-09-02

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation... Commercial Space Transportation Advisory Committee Open Meeting. SUMMARY: Pursuant to Section 10(a)(2) of the... the Commercial Space Transportation Advisory Committee (COMSTAC). The meeting will take place on...

78 FR 53497 - Commercial Space Transportation Advisory Committee; Closed Session

Science.gov (United States)

2013-08-29

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation... Commercial Space Transportation Advisory Committee Special Closed Session. SUMMARY: Pursuant to Section 10(a...), notice is hereby given of a special closed session of the Commercial Space Transportation Advisory...

78 FR 18416 - Commercial Space Transportation Advisory Committee; Open Meeting

Science.gov (United States)

2013-03-26

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation... Commercial Space Transportation Advisory Committee Open Meeting. SUMMARY: Pursuant to Section 10(a)(2) of the... the Commercial Space Transportation Advisory Committee (COMSTAC). The meeting will take place on...

Crew transportation for the 1990s. I - Commercializing manned flight with today's propulsion

Science.gov (United States)

Staehle, Robert; French, J. R.

Two commercial space transport concepts that have been developed employing reusable production engines are discussed. A winged space transport (WST) launched from a Boeing 747 was sized to carry six people to low orbit. With no margin for performance growth, it is not favored for development. A vertical launch/landing space transport was designed with capabilities and propulsion similar to the WST, but launched from the ground. A small launch mass penalty is offset by improved performance margins and by eliminating carrier aircraft costs. The two-pilot plus five-passenger vehicle is designed for short-duration trips to low earth orbit, or for docking up to 10 d at an orbiting station. Market applications include space station crew rotation, equipment delivery and product return, short-duration experiments, satellite servicing, reconnaissance, and tourism. Profitable per-mission prices are projected at $10-15 million, with development costs approaching $400 million.

76 FR 20070 - Commercial Space Transportation Safety Approval Performance Criteria

Science.gov (United States)

2011-04-11

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation... Commercial Space Transportation (AST), 800 Independence Avenue SW., Room 331, Washington, DC 20591, telephone.... Nield, Associate Administrator for Commercial Space Transportation. [FR Doc. 2011-8534 Filed 4-8-11; 8...

75 FR 16901 - Commercial Space Transportation Advisory Committee-Open Meeting

Science.gov (United States)

2010-04-02

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation... Commercial Space Transportation Advisory Committee Open meeting. SUMMARY: Pursuant to section 10(a)(2) of the... of the Commercial Space Transportation Advisory Committee (COMSTAC). The meetings will take place on...

Reusable Rocket Engine Advanced Health Management System. Architecture and Technology Evaluation: Summary

Science.gov (United States)

Pettit, C. D.; Barkhoudarian, S.; Daumann, A. G., Jr.; Provan, G. M.; ElFattah, Y. M.; Glover, D. E.

1999-01-01

In this study, we proposed an Advanced Health Management System (AHMS) functional architecture and conducted a technology assessment for liquid propellant rocket engine lifecycle health management. The purpose of the AHMS is to improve reusable rocket engine safety and to reduce between-flight maintenance. During the study, past and current reusable rocket engine health management-related projects were reviewed, data structures and health management processes of current rocket engine programs were assessed, and in-depth interviews with rocket engine lifecycle and system experts were conducted. A generic AHMS functional architecture, with primary focus on real-time health monitoring, was developed. Fourteen categories of technology tasks and development needs for implementation of the AHMS were identified, based on the functional architecture and our assessment of current rocket engine programs. Five key technology areas were recommended for immediate development, which (1) would provide immediate benefits to current engine programs, and (2) could be implemented with minimal impact on the current Space Shuttle Main Engine (SSME) and Reusable Launch Vehicle (RLV) engine controllers.

Distributed Health Monitoring System for Reusable Liquid Rocket Engines

Science.gov (United States)

Lin, C. F.; Figueroa, F.; Politopoulos, T.; Oonk, S.

2009-01-01

The ability to correctly detect and identify any possible failure in the systems, subsystems, or sensors within a reusable liquid rocket engine is a major goal at NASA John C. Stennis Space Center (SSC). A health management (HM) system is required to provide an on-ground operation crew with an integrated awareness of the condition of every element of interest by determining anomalies, examining their causes, and making predictive statements. However, the complexity associated with relevant systems, and the large amount of data typically necessary for proper interpretation and analysis, presents difficulties in implementing complete failure detection, identification, and prognostics (FDI&P). As such, this paper presents a Distributed Health Monitoring System for Reusable Liquid Rocket Engines as a solution to these problems through the use of highly intelligent algorithms for real-time FDI&P, and efficient and embedded processing at multiple levels. The end result is the ability to successfully incorporate a comprehensive HM platform despite the complexity of the systems under consideration.

78 FR 37648 - Space Transportation Infrastructure Matching (STIM) Grants Program

Science.gov (United States)

2013-06-21

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Space Transportation Infrastructure...-availability of Space Transportation Infrastructure Matching Grants in FY 2013. SUMMARY: The Office of... Administrator for Commercial Space Transportation. [FR Doc. 2013-14859 Filed 6-20-13; 8:45 am] BILLING CODE 4910...

Electrical Power Systems for NASA's Space Transportation Program

Science.gov (United States)

Lollar, Louis F.; Maus, Louis C.

1998-01-01

Marshall Space Flight Center (MSFC) is the National Aeronautics and Space Administration's (NASA) lead center for space transportation systems development. These systems include earth to orbit launch vehicles, as well as vehicles for orbital transfer and deep space missions. The tasks for these systems include research, technology maturation, design, development, and integration of space transportation and propulsion systems. One of the key elements in any transportation system is the electrical power system (EPS). Every transportation system has to have some form of electrical power and the EPS for each of these systems tends to be as varied and unique as the missions they are supporting. The Preliminary Design Office (PD) at MSFC is tasked to perform feasibility analyses and preliminary design studies for new projects, particularly in the space transportation systems area. All major subsystems, including electrical power, are included in each of these studies. Three example systems being evaluated in PD at this time are the Liquid Fly Back Booster (LFBB) system, the Human Mission to Mars (HMM) study, and a tether based flight experiment called the Propulsive Small Expendable Deployer System (ProSEDS). These three systems are in various stages of definition in the study phase.

Integrated design for space transportation system

CERN Document Server

Suresh, B N

2015-01-01

The book addresses the overall integrated design aspects of a space transportation system involving several disciplines like propulsion, vehicle structures, aerodynamics, flight mechanics, navigation, guidance and control systems, stage auxiliary systems, thermal systems etc. and discusses the system approach for design, trade off analysis, system life cycle considerations, important aspects in mission management, the risk assessment, etc. There are several books authored to describe the design aspects of various areas, viz., propulsion, aerodynamics, structures, control, etc., but there is no book which presents space transportation system (STS) design in an integrated manner. This book attempts to fill this gap by addressing systems approach for STS design, highlighting the integrated design aspects, interactions between various subsystems and interdependencies. The main focus is towards the complex integrated design to arrive at an optimum, robust and cost effective space transportation system. The orbit...

Reusable Component Services

Data.gov (United States)

U.S. Environmental Protection Agency — The Reusable Component Services (RCS) is a super-catalog of components, services, solutions and technologies that facilitates search, discovery and collaboration in...

Nonlinear transport of dynamic system phase space

International Nuclear Information System (INIS)

Xie Xi; Xia Jiawen

1993-01-01

The inverse transform of any order solution of the differential equation of general nonlinear dynamic systems is derived, realizing theoretically the nonlinear transport for the phase space of nonlinear dynamic systems. The result is applicable to general nonlinear dynamic systems, with the transport of accelerator beam phase space as a typical example

Reusable platform concepts

International Nuclear Information System (INIS)

Gudmestad, O.T.; Sparby, B.K.; Stead, B.L.

1993-01-01

There is an increasing need to reduce costs of offshore production facilities in order to make development of offshore fields profitable. For small fields with short production time there is in particular a need to investigate ways to reduce costs. The idea of platform reuse is for such fields particularly attractive. This paper will review reusable platform concepts and will discuss their range of application. Particular emphasis will be placed on technical limitations. Traditional concepts as jackups and floating production facilities will be discussed by major attention will be given to newly developed ideas for reuse of steel jackets and concrete structures. It will be shown how the operator for several fields can obtain considerable savings by applying such reusable platform concepts

Reusability Framework for Cloud Computing

OpenAIRE

Singh, Sukhpal; Singh, Rishideep

2012-01-01

Cloud based development is a challenging task for several software engineering projects, especially for those which needs development with reusability. Present time of cloud computing is allowing new professional models for using the software development. The expected upcoming trend of computing is assumed to be this cloud computing because of speed of application deployment, shorter time to market, and lower cost of operation. Until Cloud Co mputing Reusability Model is considered a fundamen...

Space tourism optimized reusable spaceplane design

Energy Technology Data Exchange (ETDEWEB)

Penn, J.P.; Lindley, C.A. [The Aerospace Corporation El Segundo, California90245-4691 (United States)

1997-01-01

Market surveys suggest that a viable space tourism industry will require flight rates about two orders of magnitude higher than those required for conventional spacelift. Although enabling round-trip cost goals for a viable space tourism business are about {dollar_sign}240 per pound ({dollar_sign}529/kg), or {dollar_sign}72,000 per passenger round-trip, goals should be about {dollar_sign}50 per pound ({dollar_sign}110/kg) or approximately {dollar_sign}15,000 for a typical passenger and baggage. The lower price will probably open space tourism to the general population. Vehicle reliabilities must approach those of commercial aircraft as closely as possible. This paper addresses the development of spaceplanes optimized for the ultra-high flight rate and high reliability demands of the space tourism mission. It addresses the fundamental operability, reliability, and cost drivers needed to satisfy this mission need. Figures of merit similar to those used to evaluate the economic viability of conventional commercial aircraft are developed, including items such as payload/vehicle dry weight, turnaround time, propellant cost per passenger, and insurance and depreciation costs, which show that infrastructure can be developed for a viable space tourism industry. A reference spaceplane design optimized for space tourism is described. Subsystem allocations for reliability, operability, and costs are made and a route to developing such a capability is discussed. The vehicle{close_quote}s ability to also satisfy the traditional spacelift market is shown. {copyright} {ital 1997 American Institute of Physics.}

An Analysis of the Advantages of Reusable Plastic Containers in Strawberry Logistics : A Case Study of the Japan Agricultural Cooperative YOICHI

OpenAIRE

尾碕, 亨; 樋元, 淳一

2014-01-01

This article undertook a comparative analysis of cardboard boxes and reusable plastic containers and their impact on production logistics costs and the receipt prices of producers. The results showed that reusable plastic containers shortened logistical working hours, reduced production logistics costs and increased the receipt prices of the producer. However, exchange-value cannot realized if the quality of the farm product is not maintained, even if it is transported in superior packing con...

Portable, parallel, reusable Krylov space codes

Energy Technology Data Exchange (ETDEWEB)

Smith, B.; Gropp, W. [Argonne National Lab., IL (United States)

1994-12-31

Krylov space accelerators are an important component of many algorithms for the iterative solution of linear systems. Each Krylov space method has it`s own particular advantages and disadvantages, therefore it is desirable to have a variety of them available all with an identical, easy to use, interface. A common complaint application programmers have with available software libraries for the iterative solution of linear systems is that they require the programmer to use the data structures provided by the library. The library is not able to work with the data structures of the application code. Hence, application programmers find themselves constantly recoding the Krlov space algorithms. The Krylov space package (KSP) is a data-structure-neutral implementation of a variety of Krylov space methods including preconditioned conjugate gradient, GMRES, BiCG-Stab, transpose free QMR and CGS. Unlike all other software libraries for linear systems that the authors are aware of, KSP will work with any application codes data structures, in Fortran or C. Due to it`s data-structure-neutral design KSP runs unchanged on both sequential and parallel machines. KSP has been tested on workstations, the Intel i860 and Paragon, Thinking Machines CM-5 and the IBM SP1.

77 FR 71474 - Commercial Space Transportation Advisory Committee-Charter Renewal

Science.gov (United States)

2012-11-30

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation... Transportation (DOT). ACTION: Announcement of Charter Renewal of the Commercial Space Transportation Advisory... Administrator of the Federal Aviation Administration (FAA) on the critical matters facing the U.S. commercial...

Transport processes in space physics and astrophysics

CERN Document Server

Zank, Gary P

2014-01-01

Transport Processes in Space Physics and Astrophysics' is aimed at graduate level students to provide the necessary mathematical and physics background to understand the transport of gases, charged particle gases, energetic charged particles, turbulence, and radiation in an astrophysical and space physics context. Subjects emphasized in the work include collisional and collisionless processes in gases (neutral or plasma), analogous processes in turbulence fields and radiation fields, and allows for a simplified treatment of the statistical description of the system. A systematic study that addresses the common tools at a graduate level allows students to progress to a point where they can begin their research in a variety of fields within space physics and astrophysics. This book is for graduate students who expect to complete their research in an area of plasma space physics or plasma astrophysics. By providing a broad synthesis in several areas of transport theory and modeling, the work also benefits resear...

Multi-Terrain Earth Landing Systems Applicable for Manned Space Capsules

Science.gov (United States)

Fasanella, Edwin L.

2008-01-01

A key element of the President's Vision for Space Exploration is the development of a new space transportation system to replace the Shuttle that will enable manned exploration of the moon, Mars, and beyond. NASA has tasked the Constellation Program with the development of this architecture, which includes the Ares launch vehicle and Orion manned spacecraft. The Orion spacecraft must carry six astronauts and its primary structure should be reusable, if practical. These requirements led the Constellation Program to consider a baseline land landing on return to earth. To assess the landing system options for Orion, a review of current operational parachute landing systems such as those used for the F-111 escape module and the Soyuz is performed. In particular, landing systems with airbags and retrorockets that would enable reusability of the Orion capsule are investigated. In addition, Apollo tests and analyses conducted in the 1960's for both water and land landings are reviewed. Finally, tests and dynamic finite element simulations to understand land landings for the Orion spacecraft are also presented.

76 FR 12211 - Commercial Space Transportation Advisory Committee-Public Teleconference

Science.gov (United States)

2011-03-04

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee--Public Teleconference AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory Committee Teleconference (COMSTAC). SUMMARY: Pursuant...

76 FR 82031 - Commercial Space Transportation Advisory Committee; Public Teleconference

Science.gov (United States)

2011-12-29

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee; Public Teleconference AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory Committee Risk Management Working Group Teleconference...

76 FR 4743 - Commercial Space Transportation Advisory Committee-Public Teleconference

Science.gov (United States)

2011-01-26

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee--Public Teleconference AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section...

75 FR 51332 - Commercial Space Transportation Advisory Committee-Public Teleconference

Science.gov (United States)

2010-08-19

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee--Public Teleconference AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section...

77 FR 48585 - Commercial Space Transportation Advisory Committee-Public Teleconference

Science.gov (United States)

2012-08-14

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee--Public Teleconference AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section...

78 FR 53496 - Commercial Space Transportation Advisory Committee; Public Teleconference

Science.gov (United States)

2013-08-29

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee; Public Teleconference AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section...

76 FR 15041 - Commercial Space Transportation Advisory Committee-Public Teleconference

Science.gov (United States)

2011-03-18

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee--Public Teleconference AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section...

76 FR 67018 - Commercial Space Transportation Advisory Committee-Public Teleconference

Science.gov (United States)

2011-10-28

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee--Public Teleconference AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section...

75 FR 38866 - Commercial Space Transportation Advisory Committee-Public Teleconference

Science.gov (United States)

2010-07-06

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee--Public Teleconference AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section...

78 FR 14401 - Commercial Space Transportation Advisory Committee; Public Teleconference

Science.gov (United States)

2013-03-05

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee; Public Teleconference AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section...

77 FR 35102 - Commercial Space Transportation Advisory Committee; Public Teleconference

Science.gov (United States)

2012-06-12

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee; Public Teleconference AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section...

77 FR 65443 - Commercial Space Transportation Advisory Committee-Public Teleconference

Science.gov (United States)

2012-10-26

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee--Public Teleconference AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section...

75 FR 52058 - Commercial Space Transportation Advisory Committee-Public Teleconference

Science.gov (United States)

2010-08-24

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee-Public Teleconference AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory Committee Teleconference. SUMMARY: Pursuant to Section 10...

Space transportation systems within ESA programmes: Current status and perspectives

Science.gov (United States)

Delahais, Maurice

1993-03-01

An overview of the space transportation aspects of the ESA (European Space Agency) programs as they result from history, present status, and decisions taken at the ministerial level conference in Granada, Spain is presented. The new factors taken into consideration for the long term plan proposed in Munich, Germany, the three strategic options for the reorientation of the ESA long term plan, and the essential elements of space transportation in the Granada long term plan in three areas of space activities, scientific, and commercial launches with expendable launch vehicles, manned flight and in-orbit infrastructure, and future transportation systems are outlined. The new ESA long term plan, in the field of space transportation systems, constitutes a reorientation of the initial program contemplated in previous councils at ministerial level. It aims at balancing the new economic situation with the new avenues of cooperation, and the outcome will be a new implementation of the space transportation systems policy.

Reusable Solid Rocket Motor - Accomplishments, Lessons, and a Culture of Success

Science.gov (United States)

Moore, Dennis R.; Phelps, Willie J.

2011-01-01

The Reusable Solid Rocket Motor represents the largest solid rocket motor ever flown and the only human rated solid motor. Each Reusable Solid Rocket Motor (RSRM) provides approximately 3-million lb of thrust to lift the integrated Space Shuttle vehicle from the launch pad. The motors burn out approximately 2 minutes later, separate from the vehicle and are recovered and refurbished. The size of the motor and the need for high reliability were challenges. Thrust shaping, via shaping of the propellant grain, was needed to limit structural loads during ascent. The motor design evolved through several block upgrades to increase performance and to increase safety and reliability. A major redesign occurred after STS-51L with the Redesigned Solid Rocket Motor. Significant improvements in the joint sealing systems were added. Design improvements continued throughout the Program via block changes with a number of innovations including development of low temperature o-ring materials and incorporation of a unique carbon fiber rope thermal barrier material. Recovery of the motors and post flight inspection improved understanding of hardware performance, and led to key design improvements. Because of the multidecade program duration material obsolescence was addressed, and requalification of materials and vendors was sometimes needed. Thermal protection systems and ablatives were used to protect the motor cases and nozzle structures. Significant understanding of design and manufacturing features of the ablatives was developed during the program resulting in optimization of design features and processing parameters. The project advanced technology in eliminating ozone-depleting materials in manufacturing processes and the development of an asbestos-free case insulation. Manufacturing processes for the large motor components were unique and safety in the manufacturing environment was a special concern. Transportation and handling approaches were also needed for the large

Project of Ariane 5 LV family advancement by use of reusable fly-back boosters (named “Bargouzine”)

Science.gov (United States)

Sumin, Yu.; Bonnal, Ch.; Kostromin, S.; Panichkin, N.

2007-12-01

The paper concerns possible concept variants of a partially reusable Heavy-Lift Launch Vehicle derived from the advanced basic launcher (Ariane-2010) by means of substitution of the EAP Solid Rocket Boosters for a Reusable Starting Stage consisting two Liquid-propellant Reusable Fly-Back Boosters called "Bargouzin". This paper describes the status of the presently studied RFBB concepts during its three phases. The first project phase was dedicated to feasibility expertise of liquid-rocket reusable fly-back boosters ("Baikal" type) utilization for heavy-lift space launch vehicle. The design features and main conclusions are presented. The second phase has been performed with the purpose of selection of preferable concept among the alternative ones for the future Ariane LV modernization by using RFBB instead of EAP Boosters. The main requirements, logic of work, possible configuration and conclusion are presented. Initial aerodynamic, ballistic, thermoloading, dynamic loading, trade-off and comparison analysis have been performed on these concepts. The third phase consists in performing a more detailed expertise of the chosen LV concept. This part summarizes some of the more detailed results related to flight performance, system mass, thermoprotection system, aspects of technologies, ground complex modification, comparison analyses and conclusion.

Commercial aspects of semi-reusable launch systems

Science.gov (United States)

Obersteiner, M. H.; Müller, H.; Spies, H.

2003-07-01

This paper presents a business planning model for a commercial space launch system. The financing model is based on market analyses and projections combined with market capture models. An operations model is used to derive the annual cash income. Parametric cost modeling, development and production schedules are used for quantifying the annual expenditures, the internal rate of return, break even point of positive cash flow and the respective prices per launch. Alternative consortia structures, cash flow methods, capture rates and launch prices are used to examine the sensitivity of the model. Then the model is applied for a promising semi-reusable launcher concept, showing the general achievability of the commercial approach and the necessary pre-conditions.

Advanced Engineering Environments for Space Transportation System Development

Science.gov (United States)

Thomas, L. Dale; Smith, Charles A.; Beveridge, James

2000-01-01

There are significant challenges facing today's launch vehicle industry. Global competition, more complex products, geographically-distributed design teams, demands for lower cost, higher reliability and safer vehicles, and the need to incorporate the latest technologies quicker, all face the developer of a space transportation system. Within NASA, multiple technology development and demonstration projects are underway toward the objectives of safe, reliable, and affordable access to space. New information technologies offer promising opportunities to develop advanced engineering environments to meet these challenges. Significant advances in the state-of-the-art of aerospace engineering practice are envisioned in the areas of engineering design and analytical tools, cost and risk tools, collaborative engineering, and high-fidelity simulations early in the development cycle. At the Marshall Space Flight Center, work has begun on development of an advanced engineering environment specifically to support the design, modeling, and analysis of space transportation systems. This paper will give an overview of the challenges of developing space transportation systems in today's environment and subsequently discuss the advanced engineering environment and its anticipated benefits.

A cislunar transportation system fuelled by lunar resources

Science.gov (United States)

Sowers, G. F.

2016-11-01

A transportation system for a self sustaining economy in cislunar space is discussed. The system is based on liquid oxygen (LO2), liquid hydrogen (LH2) propulsion whose fuels are derived from ice mined at the polar regions of the Moon. The elements of the transportation system consist of the Advanced Cryogenic Evolved Stage (ACES) and the XEUS lander, both being developed by United Launch Alliance (ULA). The main propulsion elements and structures are common between ACES and XEUS. Both stages are fully reusable with refueling of their LO2/LH2 propellants. Utilization of lunar sourced propellants has the potential to dramatically lower the cost of transportation within the cislunar environs. These lower costs dramatically lower the barriers to entry of a number of promising cislunar based activities including space solar power. One early application of the architecture is providing lunar sourced propellant to refuel ACES for traditional spacecraft deployment missions. The business case for this application provides an economic framework for a potential lunar water mining operation.

Model-Based Trade Space Exploration for Near-Earth Space Missions

Science.gov (United States)

Cohen, Ronald H.; Boncyk, Wayne; Brutocao, James; Beveridge, Iain

2005-01-01

We developed a capability for model-based trade space exploration to be used in the conceptual design of Earth-orbiting space missions. We have created a set of reusable software components to model various subsystems and aspects of space missions. Several example mission models were created to test the tools and process. This technique and toolset has demonstrated itself to be valuable for space mission architectural design.

Achievable space elevators for space transportation and starship acceleration

Science.gov (United States)

Pearson, Jerome

1990-04-01

Space elevator concepts for low-cost space launches are reviewed. Previous concepts suffered from requirements for ultra-high-strength materials, dynamically unstable systems, or from danger of collision with space debris. The use of magnetic grain streams solves these problems. Magnetic grain streams can support short space elevators for lifting payloads cheaply into Earth orbit, overcoming the material strength problem in building space elevators. Alternatively, the stream could support an international spaceport circling the Earth daily tens of miles above the equator, accessible to advanced aircraft. Mars could be equipped with a similar grain stream, using material from its moons Phobos and Deimos. Grain-stream arcs about the sun could be used for fast launches to the outer planets and for accelerating starships to near lightspeed for interstellar reconnaisance. Grain streams are essentially impervious to collisions, and could reduce the cost of space transportation by an order of magnitude.

Delayed reactions to reusable protective gloves.

Science.gov (United States)

Pontén, Ann; Dubnika, Inese

2009-04-01

The materials in plastic protective gloves are thought to cause less contact allergy than rubber gloves. Our aim was to estimate the frequency of delayed reactions to different types of reusable protective gloves among dermatitis patients. 2 x 2 cm pieces of polyvinyl chloride (PVC) gloves, nitrile gloves, and natural rubber latex (NRL) gloves were tested as is in consecutive dermatitis patients tested with the baseline series. Among 658 patients, 6 patients reacted to PVC gloves and 6 patients to the NRL gloves. None reacted to both these types of gloves. Five of six patients with reactions to rubber gloves reacted to thiuram mix in the baseline series. Delayed reactions to reusable PVC gloves may be as common as to reusable NRL gloves. In contrast to most reactions to the NRL glove, the reactions to the PVC glove had no obvious association with reactions to any allergen(s) in the baseline series.

Space transportation activities in the United States

Science.gov (United States)

Gabris, Edward A.

1994-01-01

The status of the existing space transportation systems in the U.S. and options for increased capability is being examined in the context of mission requirements, options for new vehicles, cost to operate the existing vehicles, cost to develop new vehicles, and the capabilities and plans of other suppliers. This assessment is addressing the need to build and resupply the space station, to maintain necessary military assets in a rapidly changing world, and to continue a competitive commercial space transportation industry. The Department of Defense (DOD) and NASA each conducted an 'access to space' study using a common mission model but with the emphasis on their unique requirements. Both studies considered three options: maintain and improve the existing capability, build a new launch vehicle using contemporary technology, and build a new launch vehicle using advanced technology. While no decisions have been made on a course of action, it will be influenced by the availability of funds in the U.S. budget, the changing need for military space assets, the increasing competition among space launch suppliers, and the emerging opportunity for an advanced technology, low cost system and international partnerships to develop it.

Reusability of coordination programs

NARCIS (Netherlands)

F. Arbab (Farhad); C.L. Blom (Kees); F.J. Burger (Freek); C.T.H. Everaars (Kees)

1996-01-01

textabstractIsolating computation and communication concerns into separate pure computation and pure coordination modules enhances modularity, understandability, and reusability of parallel and/or distributed software. This can be achieved by moving communication primitives (such as SendMessage and

DEPONTO: A Reusable Dependability Domain Ontology

Directory of Open Access Journals (Sweden)

Teodora Sanislav

2015-08-01

Full Text Available This paper proposes a dependability reusable ontology for knowledge representation. The fundamental knowledge related to dependability follows its taxonomy. Thus, this paper gives an analysis of what is the dependability domain ontology andof its components.The dependability domain ontology plays an important role in ensuring the dependability of information systems by providing support for their diagnosis in case of faults, errors and failures.The proposed ontology is used as a dependability framework in two case study Cyber-Physical Systemswhich demonstrate its reusability within this category of systems.

A densitometric analysis of IIaO film flown aboard the space shuttle transportation system STS #3, 7, and 8

Science.gov (United States)

Hammond, Ernest C., Jr.

1989-01-01

Since the United States of America is moving into an age of reusable space vehicles, both electronic and photographic materials will continue to be an integral part of the recording techniques available. Film as a scientifically viable recording technique in astronomy is well documented. There is a real need to expose various types of films to the Shuttle environment. Thus, the main objective was to look at the subtle densitometric changes of canisters of IIaO film that was placed aboard the Space Shuttle 3 (STS-3).

University of Tennessee Center for Space Transportation and Applied Research (CSTAR)

Science.gov (United States)

1995-10-01

The Center for Space Transportation and Applied Research had projects with space applications in six major areas: laser materials processing, artificial intelligence/expert systems, space transportation, computational methods, chemical propulsion, and electric propulsion. The closeout status of all these projects is addressed.

University of Tennessee Center for Space Transportation and Applied Research (CSTAR)

Science.gov (United States)

1995-01-01

The Center for Space Transportation and Applied Research had projects with space applications in six major areas: laser materials processing, artificial intelligence/expert systems, space transportation, computational methods, chemical propulsion, and electric propulsion. The closeout status of all these projects is addressed.

Nonlinear transport of accelerator beam phase space

International Nuclear Information System (INIS)

Xie Xi; Xia Jiawen

1995-01-01

Based on the any order analytical solution of accelerator beam dynamics, the general theory for nonlinear transport of accelerator beam phase space is developed by inverse transformation method. The method is general by itself, and hence can also be applied to the nonlinear transport of various dynamic systems in physics, chemistry and biology

Considerations when analyzing investment in space transportation business ventures

Science.gov (United States)

S. Greenberg, Joel

2000-07-01

Private sector investment in space transportation, as in most business situations, requires the development of realistic and believable business plans that demonstrate that if an investment is made that there is a reasonable chance that the indicated financial performance will attract the necessary financing. The business plan must also indicate the assumptions upon which the plan rests, and as has become almost second nature to the space transportation industry, the necessary role of the government in risk reduction and/or capital formation [i.e., government actions that are necessary to make the business venture financially attractive]. This paper discusses and describes several factors that must be considered, by both government and industry, when developing a business plan for obtaining financing for space transportation business ventures.

Quadrupole transport experiment with space charge dominated cesium ion beam

International Nuclear Information System (INIS)

Faltens, A.; Keefe, D.; Kim, C.; Rosenblum, S.; Tiefenback, M.; Warwick, A.

1984-08-01

The purpose of the experiment is to investigate the beam current transport limit in a long quadrupole-focussed transport channel in the space charge dominated region where the space charge defocussing force is almost as large as the average focussing force of the channel

On the Concepts of Usability and Reusability of Learning Objects

Directory of Open Access Journals (Sweden)

Miguel-Angel Sicilia

2003-10-01

Full Text Available “Reusable learning objects” oriented towards increasing their potential reusability are required to satisfy concerns about their granularity and their independence of concrete contexts of use. Such requirements also entail that the definition of learning object “usability,” and the techniques required to carry out their “usability evaluation” must be substantially different from those commonly used to characterize and evaluate the usability of conventional educational applications. In this article, a specific characterization of the concept of learning object usability is discussed, which places emphasis on “reusability,” the key property of learning objects residing in repositories. The concept of learning object reusability is described as the possibility and adequacy for the object to be usable in prospective educational settings, so that usability and reusability are considered two interrelated – and in many cases conflicting – properties of learning objects. Following the proposed characterization of two characteristics or properties of learning objects, a method to evaluate usability of specific learning objects will be presented.

Research Data Reusability: Conceptual Foundations, Barriers and Enabling Technologies

Directory of Open Access Journals (Sweden)

Costantino Thanos

2017-01-01

Full Text Available High-throughput scientific instruments are generating massive amounts of data. Today, one of the main challenges faced by researchers is to make the best use of the world’s growing wealth of data. Data (reusability is becoming a distinct characteristic of modern scientific practice. By data (reusability, we mean the ease of using data for legitimate scientific research by one or more communities of research (consumer communities that is produced by other communities of research (producer communities. Data (reusability allows the reanalysis of evidence, reproduction and verification of results, minimizing duplication of effort, and building on the work of others. It has four main dimensions: policy, legal, economic and technological. The paper addresses the technological dimension of data reusability. The conceptual foundations of data reuse as well as the barriers that hamper data reuse are presented and discussed. The data publication process is proposed as a bridge between the data author and user and the relevant technologies enabling this process are presented.

Hospital information system: reusability, designing, modelling, recommendations for implementing.

Science.gov (United States)

Huet, B

1998-01-01

The aims of this paper are to precise some essential conditions for building reuse models for hospital information systems (HIS) and to present an application for hospital clinical laboratories. Reusability is a general trend in software, however reuse can involve a more or less part of design, classes, programs; consequently, a project involving reusability must be precisely defined. In the introduction it is seen trends in software, the stakes of reuse models for HIS and the special use case constituted with a HIS. The main three parts of this paper are: 1) Designing a reuse model (which objects are common to several information systems?) 2) A reuse model for hospital clinical laboratories (a genspec object model is presented for all laboratories: biochemistry, bacteriology, parasitology, pharmacology, ...) 3) Recommendations for generating plug-compatible software components (a reuse model can be implemented as a framework, concrete factors that increase reusability are presented). In conclusion reusability is a subtle exercise of which project must be previously and carefully defined.

Space Geodesy Monitoring Mass Transport in Global Geophysical Fluids

Science.gov (United States)

Chao, Benjamin F.

2004-01-01

Mass transports occurring in the atmosphere-hydrosphere-cryosphere-solid Earth-core system (the 'global geophysical fluids') are important geophysical phenomena. They occur on all temporal and spatial scales. Examples include air mass and ocean circulations, oceanic and solid tides, hydrological water and idsnow redistribution, mantle processes such as post-glacial rebound, earthquakes and tectonic motions, and core geodynamo activities. The temporal history and spatial pattern of such mass transport are often not amenable to direct observations. Space geodesy techniques, however, have proven to be an effective tool in monitorihg certain direct consequences of the mass transport, including Earth's rotation variations, gravitational field variations, and the geocenter motion. Considerable advances have been made in recent years in observing and understanding of these geodynamic effects. This paper will use several prominent examples to illustrate the triumphs in research over the past years under a 'Moore's law' in space geodesy. New space missions and projects promise to further advance our knowledge about the global mass transports. The latter contributes to our understanding of the geophysical processes that produce and regulate the mass transports, as well as of the solid Earth's response to such changes in terms of Earth's mechanical properties.

NASP - Enabling new space launch options

Science.gov (United States)

Froning, David; Gaubatz, William; Mathews, George

1990-10-01

Successful NASP developments in the United States are bringing about the possibility of effective, fully reusable vehicles for transport of people and cargo between earth and space. These developments include: extension of airbreathing propulsion to a much higher speed; densification of propellants for greater energy per unit volume of mass; structures with much greater strength-to-weight at high temperatures; computational advancements that enable more optimal design and integration of airframes, engines and controls; and advances in avionics, robotics, artificial intelligence and automation that enable accomplishment of earth-to-orbit (ETO) operations with much less manpower support and cost. This paper describes the relative magnitude of improvement that these developments may provide.

Indian space transportation programme: Near term outlook and issues for commercialisation

Science.gov (United States)

Nagendra, Narayan Prasad

2015-05-01

The Indian space transportation programme has grown from strength to strength with the launching of sounding rockets in the 60's to the development of heavy lift vehicles for telecommunication satellites in the present decade. With the growing market confidence in Indian Space Research Organisation's ability to reliably deliver payloads to low Earth orbit with its Polar Satellite Launch Vehicle, there is an inherent opportunity for India to cater to the commercial market. The present work assesses the current launch capacity of India in retrospect of international launches and provides India's outlook for the space transportation in the current decade. Launch capacity correlation with the requirements within the Indian space programme as well as the current space transportation infrastructure have been considered to identify bottlenecks in catering to the current national requirements alongside securing a greater market share in the international launch market. The state of commercialisation of launch vehicle development has been presented to provide an overview of policy and organisational issues for commercialisation of space transportation in India.

Space-Time Dependent Transport, Activation, and Dose Rates for Radioactivated Fluids.

Science.gov (United States)

Gavazza, Sergio

Two methods are developed to calculate the space - and time-dependent mass transport of radionuclides, their production and decay, and the associated dose rates generated from the radioactivated fluids flowing through pipes. The work couples space- and time-dependent phenomena, treated as only space- or time-dependent in the open literature. The transport and activation methodology (TAM) is used to numerically calculate space- and time-dependent transport and activation of radionuclides in fluids flowing through pipes exposed to radiation fields, and volumetric radioactive sources created by radionuclide motions. The computer program Radionuclide Activation and Transport in Pipe (RNATPA1) performs the numerical calculations required in TAM. The gamma ray dose methodology (GAM) is used to numerically calculate space- and time-dependent gamma ray dose equivalent rates from the volumetric radioactive sources determined by TAM. The computer program Gamma Ray Dose Equivalent Rate (GRDOSER) performs the numerical calculations required in GAM. The scope of conditions considered by TAM and GAM herein include (a) laminar flow in straight pipe, (b)recirculating flow schemes, (c) time-independent fluid velocity distributions, (d) space-dependent monoenergetic neutron flux distribution, (e) space- and time-dependent activation process of a single parent nuclide and transport and decay of a single daughter radionuclide, and (f) assessment of space- and time-dependent gamma ray dose rates, outside the pipe, generated by the space- and time-dependent source term distributions inside of it. The methodologies, however, can be easily extended to include all the situations of interest for solving the phenomena addressed in this dissertation. A comparison is made from results obtained by the described calculational procedures with analytical expressions. The physics of the problems addressed by the new technique and the increased accuracy versus non -space and time-dependent methods

Product Lifecycle Management and the Quest for Sustainable Space Transportation Solutions

Science.gov (United States)

Caruso, Pamela W.

2009-01-01

This viewgraph presentation reviews NASA Marshall's effort to sustain space transportation solutions through product lines that include: 1) Propulsion and Transportation Systems; 2) Life Support Systems; and 3) and Earth and Space Science Spacecraft Systems, and Operations.

Putting Reusability First: A Paradigm Switch in Remote Laboratories Engineering

Directory of Open Access Journals (Sweden)

Romain Vérot

2009-02-01

Full Text Available In this paper, we present a new devices brought online thanks to our Collaborative Remote Laboratories framework. Whereas previous devices integrated in our remote laboratory belongs to the domain of electronics, such as Vector Network Analyzers, the devices at the concern in this paper are, on one hand, an antenna workbench, and on the other, an homemade switching device, which embeds several electronic components. Because the middleware and framework for our environment were designed to be reusable, we wanted to put it to the test by integrating new and different devices in our Online Engineering catalog. After presenting the devices to be put online, we will expose the software development efforts required in regards to the reusability of the solution. As a consequence, the expose work and results tend to make the Online Engineering software architects to think reusability first, breaking with the current trends to implement Remote Labs one after the other, without much reusability, apart the capitalized experience. In this, we defend a paradigm switch in our current engineering approaches for Remote Laboratories implementations: Reusability should be thought first.

SpaceX making commercial spaceflight a reality

CERN Document Server

Seedhouse, Erik

2013-01-01

2012 - the year when the first ever privately-developed spacecraft visited the International Space Station. This is the story of how one company is transforming commercial space flight. It describes the extraordinary feats of engineering and human achievement that have resulted in the world's first fully reusable launch vehicles and the prospect of human travel to Mars. SpaceX - The First Ten Years: - explores the philosophy behind the success of SpaceX; - explains the practical management that enables SpaceX to keep it simple, reliable, and affordable; - details the developmentof the Falcon 1, Falcon 9 and Falcon Heavy rockets and the technology of the Merlin engines; - describes the collaboration with NASA; - introduces current SpaceX projects, including the Grasshopper reusable launch vehicle and the Stratolaunch System. SpaceX - The First Ten Years is a portrait of one of the most spectacular spaceflight triumphs of the 21st century, one that is laying the foundation for humanity to become a spacefaring c...

Future space transportation systems systems analysis study, phase 1 technical report

Science.gov (United States)

1975-01-01

The requirements of projected space programs (1985-1995) for transportation vehicles more advanced than the space shuttle are discussed. Several future program options are described and their transportation needs are analyzed. Alternative systems approaches to meeting these needs are presented.

Methodology for Evaluating Quality and Reusability of Learning Objects

Science.gov (United States)

Kurilovas, Eugenijus; Bireniene, Virginija; Serikoviene, Silvija

2011-01-01

The aim of the paper is to present the scientific model and several methods for the expert evaluation of quality of learning objects (LOs) paying especial attention to LOs reusability level. The activities of eQNet Quality Network for a European Learning Resource Exchange (LRE) aimed to improve reusability of LOs of European Schoolnet's LRE…

Reusable Rocket Engine Turbopump Health Management System

Science.gov (United States)

Surko, Pamela

1994-01-01

A health monitoring expert system software architecture has been developed to support condition-based health monitoring of rocket engines. Its first application is in the diagnosis decisions relating to the health of the high pressure oxidizer turbopump (HPOTP) of Space Shuttle Main Engine (SSME). The post test diagnostic system runs off-line, using as input the data recorded from hundreds of sensors, each running typically at rates of 25, 50, or .1 Hz. The system is invoked after a test has been completed, and produces an analysis and an organized graphical presentation of the data with important effects highlighted. The overall expert system architecture has been developed and documented so that expert modules analyzing other line replaceable units may easily be added. The architecture emphasizes modularity, reusability, and open system interfaces so that it may be used to analyze other engines as well.

Software Atom: An approach towards software components structuring to improve reusability

Directory of Open Access Journals (Sweden)

Muhammad Hussain Mughal

2017-12-01

Full Text Available Diversity of application domain compelled to design sustainable classification scheme for significantly amassing software repository. The atomic reusable software components are articulated to improve the software component reusability in volatile industry.  Numerous approaches of software classification have been proposed over past decades. Each approach has some limitations related to coupling and cohesion. In this paper, we proposed a novel approach by constituting the software based on radical functionalities to improve software reusability. We analyze the element's semantics in Periodic Table used in chemistry to design our classification approach, and present this approach using tree-based classification to curtail software repository search space complexity and further refined based on semantic search techniques. We developed a Global unique Identifier (GUID for indexing the functions and related components. We have exploited the correlation between chemistry element and software elements to simulate one to one mapping between them. Our approach is inspired from sustainability chemical periodic table. We have proposed software periodic table (SPT representing atomic software components extracted from real application software. Based on SPT classified repository tree parsing & extraction to enable the user to program their software by customizing the ingredients of software requirements. The classified repository of software ingredients assist user to exploits their requirements to software engineer and enable requirement engineer to develop a rapid large-scale prototype with great essence. Furthermore, we would predict the usability of the categorized repository based on feedback of users.  The continuous evolution of that proposed repository will be fine-tuned based on utilization and SPT would be gradually optimized by ant colony optimization techniques. Succinctly would provoke automating the software development process.

Building of Reusable Reverse Logistics Model and its Optimization Considering the Decision of Backorder or Next Arrival of Goods

Science.gov (United States)

Lee, Jeong-Eun; Gen, Mitsuo; Rhee, Kyong-Gu; Lee, Hee-Hyol

This paper deals with the building of the reusable reverse logistics model considering the decision of the backorder or the next arrival of goods. The optimization method to minimize the transportation cost and to minimize the volume of the backorder or the next arrival of goods occurred by the Just in Time delivery of the final delivery stage between the manufacturer and the processing center is proposed. Through the optimization algorithms using the priority-based genetic algorithm and the hybrid genetic algorithm, the sub-optimal delivery routes are determined. Based on the case study of a distilling and sale company in Busan in Korea, the new model of the reusable reverse logistics of empty bottles is built and the effectiveness of the proposed method is verified.

Transport regimes spanning magnetization-coupling phase space

Science.gov (United States)

Baalrud, Scott D.; Daligault, Jérôme

2017-10-01

The manner in which transport properties vary over the entire parameter-space of coupling and magnetization strength is explored. Four regimes are identified based on the relative size of the gyroradius compared to other fundamental length scales: the collision mean free path, Debye length, distance of closest approach, and interparticle spacing. Molecular dynamics simulations of self-diffusion and temperature anisotropy relaxation spanning the parameter space are found to agree well with the predicted boundaries. Comparison with existing theories reveals regimes where they succeed, where they fail, and where no theory has yet been developed.

National Space Transportation System (NSTS) technology needs

Science.gov (United States)

Winterhalter, David L.; Ulrich, Kimberly K.

1990-01-01

The National Space Transportation System (NSTS) is one of the Nation's most valuable resources, providing manned transportation to and from space in support of payloads and scientific research. The NSTS program is currently faced with the problem of hardware obsolescence, which could result in unacceptable schedule and cost impacts to the flight program. Obsolescence problems occur because certain components are no longer being manufactured or repair turnaround time is excessive. In order to achieve a long-term, reliable transportation system that can support manned access to space through 2010 and beyond, NASA must develop a strategic plan for a phased implementation of enhancements which will satisfy this long-term goal. The NSTS program has initiated the Assured Shuttle Availability (ASA) project with the following objectives: eliminate hardware obsolescence in critical areas, increase reliability and safety of the vehicle, decrease operational costs and turnaround time, and improve operational capability. The strategy for ASA will be to first meet the mandatory needs - keep the Shuttle flying. Non-mandatory changes that will improve operational capability and enhance performance will then be considered if funding is adequate. Upgrade packages should be developed to install within designated inspection periods, grouped in a systematic approach to reduce cost and schedule impacts, and allow the capability to provide a Block 2 Shuttle (Phase 3).

Making the Case for Reusable Booster Systems: The Operations Perspective

Science.gov (United States)

Zapata, Edgar

2012-01-01

Presentation to the Aeronautics Space Engineering Board National Research Council Reusable Booster System: Review and Assessment Committee. Addresses: the criteria and assumptions used in the formulation of current RBS plans; the methodologies used in the current cost estimates for RBS; the modeling methodology used to frame the business case for an RBS capability including: the data used in the analysis, the models' robustness if new data become available, and the impact of unclassified government data that was previously unavailable and which will be supplied by the USAF; the technical maturity of key elements critical to RBS implementation and the ability of current technology development plans to meet technical readiness milestones.

Economics of reusable facilities

International Nuclear Information System (INIS)

Antia, D.D.J.

1992-01-01

In this paper some of the different economic development strategies that can be used for reusable facilities in the UK, Norway, Netherlands and in some production sharing contracts are outlined. These strategies focus on an integrated decision analysis approach which considers development phasing, reservoir management, tax planning and where appropriate facility purchase, leasing, or sale and leaseback decisions

76 FR 15039 - Commercial Space Transportation Grants Program

Science.gov (United States)

2011-03-18

... infrastructure system, which supports the National Space Policy and Congressional intent. Begun in 2010, the... funding for Commercial Space Transportation infrastructure projects. It must be noted that with the FY... deadline, pursuant to 49 United States Code (U.S.C.) Chapter 703 (to be recodified at 51 U.S.C. Chapter 511...

Space transportation propulsion USSR launcher technology, 1990

Science.gov (United States)

1991-01-01

Space transportation propulsion U.S.S.R. launcher technology is discussed. The following subject areas are covered: Energia background (launch vehicle summary, Soviet launcher family) and Energia propulsion characteristics (booster propulsion, core propulsion, and growth capability).

Differences in alarm events between disposable and reusable electrocardiography lead wires.

Science.gov (United States)

Albert, Nancy M; Murray, Terri; Bena, James F; Slifcak, Ellen; Roach, Joel D; Spence, Jackie; Burkle, Alicia

2015-01-01

Disposable electrocardiographic lead wires (ECG-LWs) may not be as durable as reusable ones. To examine differences in alarm events between disposable and reusable ECG-LWs. Two cardiac telemetry units were randomized to reusable ECG-LWs, and 2 units alternated between disposable and reusable ECG-LWs for 4 months. A remote monitoring team, blinded to ECG-LW type, assessed frequency and type of alarm events by using total counts and rates per 100 patient days. Event rates were compared by using generalized linear mixed-effect models for differences and noninferiority between wire types. In 1611 patients and 9385.5 patient days of ECG monitoring, patient characteristics were similar between groups. Rates of alarms for no telemetry, leads fail, or leads off were lower in disposable ECG-LWs (adjusted relative risk [95% CI], 0.71 [0.53-0.96]; noninferiority P < .001; superiority P = .03) and monitoring (artifact) alarms were significantly noninferior (adjusted relative risk [95% CI]: 0.88, [0.62-1.24], P = .02; superiority P = .44). No between-group differences existed in false or true crisis alarms. Disposable ECG-LWs were noninferior to reusable ECG-LWs for all false-alarm events (N [rate per 100 patient days], disposable 2029 [79.1] vs reusable 6673 [97.9]; adjusted relative risk [95% CI]: 0.81 [0.63-1.06], P = .002; superiority P = .12.) Disposable ECG-LWs with patented push-button design had superior performance in reducing alarms created by no telemetry, leads fail, or leads off and significant noninferiority in all false-alarm rates compared with reusable ECG-LWs. Fewer ECG alarms may save nurses time, decrease alarm fatigue, and improve patient safety. ©2015 American Association of Critical-Care Nurses.

Final report of the SPS space transportation workshop

Energy Technology Data Exchange (ETDEWEB)

1980-10-01

After a brief description of space power system concepts and the current status of the SPS program, issues relevant to earth-surface-to-low-earth-orbit (ESLEO) and orbit-to-orbit transport are discussed. For ESLEO, vehicle concepts include shuttle transportation systems, heavy lift launch vehicles, and single-stage-to-orbit vehicles. Orbit transfer vehicle missions include transport of cargo and the SPS module from low earth orbit to geosynchronous earth orbit as well as personnel transport. Vehicles discussed for such missions include chemical rocket orbital transfer vehicles, and electric orbital transfer vehicles. Further discussions include SPS station-keeping and attitude control, intra-orbit transport, and advanced propulsion and vehicle concepts. (LEW)

Reusable radiation monitor

International Nuclear Information System (INIS)

Fanselow, D.L.; Ersfeld, D.A.

1978-01-01

An integrating, reusable device for monitoring exposure to actinic radiation is disclosed. The device comprises a substrate having deposited thereon at least one photochromic aziridine compound which is sealed in an oxygen barrier to stabilize the color developed by the aziridine compound in response to actinic radiation. The device includes a spectral response shaping filter to transmit only actinic radiation of the type being monitored. A color standard is also provided with which to compare the color developed by the aziridine compound

Space transportation. [user needs met by information derived from satellites and the interface with space transportation systems

Science.gov (United States)

1975-01-01

User-oriented panels were formed to examine practical applications of information or services derived from earth orbiting satellites. Topics discussed include: weather and climate; uses of communication; land use planning; agriculture, forest, and range; inland water resources; retractable resources; environmental quality; marine and maritime uses; and materials processing in space. Emphasis was placed on the interface of the space transportation system (STS) with the applications envisioned by the user panels. User requirements were compared with expected STS capabilities in terms of availability, carrying payload to orbit, and estimated costs per launch. Conclusions and recommendations were reported.

T-SDN architecture for space and ground integrated optical transport network

Science.gov (United States)

Nie, Kunkun; Hu, Wenjing; Gao, Shenghua; Chang, Chengwu

2015-11-01

Integrated optical transport network is the development trend of the future space information backbone network. The space and ground integrated optical transport network(SGIOTN) may contain a variety of equipment and systems. Changing the network or meeting some innovation missions in the network will be an expensive implement. Software Defined Network(SDN) provides a good solution to flexibly adding process logic, timely control states and resources of the whole network, as well as shielding the differences of heterogeneous equipment and so on. According to the characteristics of SGIOTN, we propose an transport SDN architecture for it, with hierarchical control plane and data plane composed of packet networks and optical transport networks.

The Nuclear Thermal Propulsion Stage (NTPS): A Key Space Asset for Human Exploration and Commercial Missions to the Moon

Science.gov (United States)

Borowski, Stanley K.; McCurdy, David R.; Burke, Laura M.

2014-01-01

The nuclear thermal rocket (NTR) has frequently been discussed as a key space asset that can bridge the gap between a sustained human presence on the Moon and the eventual human exploration of Mars. Recently, a human mission to a near Earth asteroid (NEA) has also been included as a "deep space precursor" to an orbital mission of Mars before a landing is attempted. In his "post-Apollo" Integrated Space Program Plan (1970 to 1990), Wernher von Braun, proposed a reusable Nuclear Thermal Propulsion Stage (NTPS) to deliver cargo and crew to the Moon to establish a lunar base initially before sending human missions to Mars. The NTR was selected because it was a proven technology capable of generating both high thrust and high specific impulse (Isp approx. 900 s)-twice that of today's best chemical rockets. During the Rover and NERVA programs, 20 rocket reactors were designed, built and successfully ground tested. These tests demonstrated the (1) thrust levels; (2) high fuel temperatures; (3) sustained operation; (4) accumulated lifetime; and (5) restart capability needed for an affordable in-space transportation system. In NASA's Mars Design Reference Architecture (DRA) 5.0 study, the "Copernicus" crewed NTR Mars transfer vehicle used three 25 klbf "Pewee" engines-the smallest and highest performing engine tested in the Rover program. Smaller lunar transfer vehicles-consisting of a NTPS with three approx. 16.7 klbf "SNRE-class" engines, an in-line propellant tank, plus the payload-can be delivered to LEO using a 70 t to LEO upgraded SLS, and can support reusable cargo delivery and crewed lunar landing missions. The NTPS can play an important role in returning humans to the Moon to stay by providing an affordable in-space transportation system that can allow initial lunar outposts to evolve into settlements capable of supporting commercial activities. Over the next decade collaborative efforts between NASA and private industry could open up new exploration and commercial

A Path Space Extension for Robust Light Transport Simulation

DEFF Research Database (Denmark)

Hachisuka, Toshiya; Pantaleoni, Jacopo; Jensen, Henrik Wann

2012-01-01

We present a new sampling space for light transport paths that makes it possible to describe Monte Carlo path integration and photon density estimation in the same framework. A key contribution of our paper is the introduction of vertex perturbations, which extends the space of paths with loosely...

Long-haul transportation of perishable products with transshipment and asset management issues

NARCIS (Netherlands)

SteadieSeifi, Maryam; Dellaert, Nico; Van Woensel, Tom

2014-01-01

In this paper, we present an optimization model for a transportation planning problem with multiple transportation modes, highly perishable products, demand and supply dynamics, and management of the reusable transport units (RTIs). Such a problem arises in the European horticultural chain, for

TRANSPORT AND EMPLACEMENT EQUIPMENT DESCRIPTIONS

International Nuclear Information System (INIS)

1997-01-01

The objective and the scope of this document are to list and briefly describe the major mobile equipment necessary for waste package (WP) Transport and Emplacement in the proposed subsurface nuclear waste repository at Yucca Mountain. Primary performance characteristics and some specialized design features of the equipment are explained and summarized in the individual subsections of this document. The Transport and Emplacement equipment described in this document consists of the following: (1) WP Transporter; (2) Reusable Rail Car; (3) Emplacement Gantry; (4) Gantry Carrier; and (5) Transport Locomotive

Longitudinal and transverse space charge limitations on transport of maximum power beams

International Nuclear Information System (INIS)

Khoe, T.K.; Martin, R.L.

1977-01-01

The maximum transportable beam power is a critical issue in selecting the most favorable approach to generating ignition pulses for inertial fusion with high energy accelerators. Maschke and Courant have put forward expressions for the limits on transport power for quadrupole and solenoidal channels. Included in a more general way is the self consistent effect of space charge defocusing on the power limit. The results show that no limits on transmitted power exist in principal. In general, quadrupole transport magnets appear superior to solenoids except for transport of very low energy and highly charged particles. Longitudinal space charge effects are very significant for transport of intense beams

'Complexity' and anomalous transport in space plasmas

International Nuclear Information System (INIS)

Chang, Tom; Wu Chengchin

2002-01-01

'Complexity' has become a hot topic in nearly every field of modern physics. Space plasma is of no exception. In this paper, it is demonstrated that the sporadic and localized interactions of magnetic coherent structures are the origin of 'complexity' in space plasmas. The intermittent localized interactions, which generate the anomalous diffusion, transport, and evolution of the macroscopic state variables of the overall dynamical system, may be modeled by a triggered (fast) localized chaotic growth equation of a set of relevant order parameters. Such processes would generally pave the way for the global system to evolve into a 'complex' state of long-ranged interactions of fluctuations, displaying the phenomenon of forced and/or self-organized criticality. An example of such type of anomalous transport and evolution in a sheared magnetic field is provided via two-dimensional magnetohydrodynamic simulations. The coarse-grained dissipation due to the intermittent triggered interactions among the magnetic coherent structures induces a 'fluctuation-induced nonlinear instability' that reconfigures the sheared magnetic field into an X-point magnetic geometry (in the mean field sense), leading to the anomalous acceleration of the magnetic coherent structures. A phenomenon akin to such type of anomalous transport and acceleration, the so-called bursty bulk flows, has been commonly observed in the plasma sheet of the Earth's magnetotail

Space Transportation and the Computer Industry: Learning from the Past

Science.gov (United States)

Merriam, M. L.; Rasky, D.

2002-01-01

Since the space shuttle began flying in 1981, NASA has made a number of attempts to advance the state of the art in space transportation. In spite of billions of dollars invested, and several concerted attempts, no replacement for the shuttle is expected before 2010. Furthermore, the cost of access to space has dropped very slowly over the last two decades. On the other hand, the same two decades have seen dramatic progress in the computer industry. Computational speeds have increased by about a factor of 1000 and available memory, disk space, and network bandwidth has seen similar increases. At the same time, the cost of computing has dropped by about a factor of 10000. Is the space transportation problem simply harder? Or is there something to be learned from the computer industry? In looking for the answers, this paper reviews the early history of NASA's experience with supercomputers and NASA's visionary course change in supercomputer procurement strategy.

Economic Analysis on the Space Transportation Architecture Study (STAS) NASA Team

Science.gov (United States)

Shaw, Eric J.

1999-01-01

The National Aeronautics and Space Administration (NASA) performed the Space Transportation Architecture Study (STAS) to provide information to support end-of-the-decade decisions on possible near-term US Government (USG) investments in space transportation. To gain a clearer understanding of the costs and benefits of the broadest range of possible space transportation options, six teams, five from aerospace industry companies and one internal to NASA, were tasked to answer three primary questions: a) If the Space Shuttle system should be replaced; b) If so, when the replacement should take place and how the transition should be implemented; and c) If not, what is the upgrade strategy to continue safe and affordable flight of the Space Shuttle beyond 2010. The overall goal of the Study was "to develop investment options to be considered by the Administration for the President's FY2001 budget to meet NASA's future human space flight requirements with significant reductions in costs." This emphasis on government investment, coupled with the participation by commercial f'trms, required an unprecedented level of economic analysis of costs and benefits from both industry and government viewpoints. This paper will discuss the economic and market models developed by the in-house NASA Team to analyze space transportation architectures, the results of those analyses, and how those results were reflected in the conclusions and recommendations of the STAS NASA Team. Copyright 1999 by the American Institute of Aeronautics and Astronautics, Inc. No copyright is asserted in the United States under Title 17, U.$. Code. The U.S. Government has a royalty-free license to exercise all rights under the copyright claimed herein for Governmental purposes. All other rights are reserved by the copyright owner.

Performance of Single-Use FlexorVue vs Reusable BoaVision Ureteroscope for Visualization of Calices and Stone Extraction in an Artificial Kidney Model.

Science.gov (United States)

Schlager, Daniel; Hein, Simon; Obaid, Moaaz Abdulghani; Wilhelm, Konrad; Miernik, Arkadiusz; Schoenthaler, Martin

2017-11-01

To evaluate and compare Flexor ® Vue™, a semidisposable endoscopic deflection system with disposable ureteral sheath and reusable visualization source, and a nondisposable fiber optic ureteroscope in a standard in vitro setting. FlexorVue and a reusable fiber optic flexible ureteroscope were each tested in an artificial kidney model. The experimental setup included the visualization of colored pearls and the extraction of calculi with two different extraction devices (NCircle ® and NGage ® ). The procedures were performed by six experienced surgeons. Visualization time, access to calices, successful stone retraction, and time required were recorded. In addition, the surgeons' workload and subjective performance were determined according to the National Aeronautics and Space Administration-task load index (NASA-TLX). We referred to the Likert scale to assess maneuverability, handling, and image quality. Nearly all calices (99%) were correctly identified using the reusable scope, indicating full kidney access, whereas 74% of the calices were visualized using FlexorVue, of which 81% were correctly identified. Access to the lower poles of the kidney model was significantly less likely with the disposable device, and time to completion was significantly longer (755 s vs 153 s, p NASA-TLX scores were significantly higher using FlexorVue. The conventional reusable device also demonstrated superior maneuverability, handling, and image quality. FlexorVue offers a semidisposable deflecting endoscopic system allowing basic ureteroscopic and cystoscopic procedures. For its use as an addition or replacement for current reusable scopes, it requires substantial technical improvements.

An Integrated Hybrid Transportation Architecture for Human Mars Expeditions

Science.gov (United States)

Merrill, Raymond G.; Chai, Patrick R.; Qu, Min

2015-01-01

NASA's Human Spaceflight Architecture Team is developing a reusable hybrid transportation architecture that uses both chemical and electric propulsion systems on the same vehicle to send crew and cargo to Mars destinations such as Phobos, Deimos, the surface of Mars, and other orbits around Mars. By applying chemical and electrical propulsion where each is most effective, the hybrid architecture enables a series of Mars trajectories that are more fuel-efficient than an all chemical architecture without significant increases in flight times. This paper presents an integrated Hybrid in-space transportation architecture for piloted missions and delivery of cargo. A concept for a Mars campaign including orbital and Mars surface missions is described in detail including a system concept of operations and conceptual design. Specific constraints, margin, and pinch points are identified for the architecture and opportunities for critical path commercial and international collaboration are discussed.

Validation of comprehensive space radiation transport code

International Nuclear Information System (INIS)

Shinn, J.L.; Simonsen, L.C.; Cucinotta, F.A.

1998-01-01

The HZETRN code has been developed over the past decade to evaluate the local radiation fields within sensitive materials on spacecraft in the space environment. Most of the more important nuclear and atomic processes are now modeled and evaluation within a complex spacecraft geometry with differing material components, including transition effects across boundaries of dissimilar materials, are included. The atomic/nuclear database and transport procedures have received limited validation in laboratory testing with high energy ion beams. The codes have been applied in design of the SAGE-III instrument resulting in material changes to control injurious neutron production, in the study of the Space Shuttle single event upsets, and in validation with space measurements (particle telescopes, tissue equivalent proportional counters, CR-39) on Shuttle and Mir. The present paper reviews the code development and presents recent results in laboratory and space flight validation

Reusability of photocatalytic TiO{sub 2} and ZnO nanoparticles immobilized in poly(vinylidene difluoride)-co-trifluoroethylene

Energy Technology Data Exchange (ETDEWEB)

Teixeira, Sara, E-mail: sara.teixeira@nano.tu-dresden.de [Institute for Materials Science and Max Bergmann Center of Biomaterials, TU Dresden, 01062 Dresden (Germany); Martins, P.M. [Centro/Departamento de Física da Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Centro de Engenharia Biológica, Universidade do Minho, 4710-057 Braga (Portugal); Lanceros-Méndez, S. [Centro/Departamento de Física da Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); BCMaterials, Parque Científico y Tecnológico de Bizkaia, 48160 Derio (Spain); IKERBASQUE, Basque Foundation for Science, Bilbao (Spain); Kühn, Klaus [Institute for Materials Science and Max Bergmann Center of Biomaterials, TU Dresden, 01062 Dresden (Germany); Cuniberti, Gianaurelio [Institute for Materials Science and Max Bergmann Center of Biomaterials, TU Dresden, 01062 Dresden (Germany); Dresden Center for Computational Materials Science (DCCMS), TU Dresden, 01062 Dresden (Germany); Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden (Germany)

2016-10-30

Highlights: • Performance of immobilized TiO{sub 2} and ZnO nanoparticles in P(VDF-TrFE) membranes. • Photocatalytic degradation of methylene blue under UV radiation. • Assessment of the reusability of the nanocomposites. • Ecofriendly and cost-effective process for water treatment. - Abstract: Pollutants present in water are increasingly becoming an important public health issue. After their transportation across the sewer network they can pass through the wastewater treatment plants (WWTPs) mostly unchanged because WWTPs are not designed to remove pollutants present at trace levels. Conventional treatments are therefore ineffective. Immobilized photocatalytic systems are thus an advantage for the treatment of contaminated water, because they are ecofriendly, cost-effective and allow reusability. This work reports on TiO{sub 2} and ZnO commercial nanoparticles immobilized in poly(vinylidene difluoride)-co-trifluoroethylene (P(VDF-TrFE)). Nanocomposites of P(VDF-TrFE) with different concentrations of TiO{sub 2} nanoparticles (5, 10, and 15 wt.%) and ZnO nanoparticles (15 wt.%) were produced by solvent casting and tested on the degradation of methylene blue, a model organic dye. Each nanocomposite was tested three times to assess its reusability. It is shown that increasing the photocatalyst concentration results in higher photocatalytic efficiencies; the degradation rates of 15% of TiO{sub 2} and ZnO are similar; and the photoactivity decreases 6%, 16%, 13%, and 11% after three utilizations, for TiO{sub 2} 5%, TiO{sub 2} 10%, TiO{sub 2} 15%, and ZnO 15%, respectively. Thus, the low decrease in the photocatalytic activity after three uses makes the nanocomposites suitable for applications in which reusability is an important key factor.

Lunar transportation scenarios utilising the Space Elevator.

Science.gov (United States)

Engel, Kilian A

2005-01-01

The Space Elevator (SE) concept has begun to receive an increasing amount of attention within the space community over the past couple of years and is no longer widely dismissed as pure science fiction. In light of the renewed interest in a, possibly sustained, human presence on the Moon and the fact that transportation and logistics form the bottleneck of many conceivable lunar missions, it is interesting to investigate what role the SE could eventually play in implementing an efficient Earth to Moon transportation system. The elevator allows vehicles to ascend from Earth and be injected into a trans-lunar trajectory without the use of chemical thrusters, thus eliminating gravity loss, aerodynamic loss and the need of high thrust multistage launch systems. Such a system therefore promises substantial savings of propellant and structural mass and could greatly increase the efficiency of Earth to Moon transportation. This paper analyzes different elevator-based trans-lunar transportation scenarios and characterizes them in terms of a number of benchmark figures. The transportation scenarios include direct elevator-launched trans-lunar trajectories, elevator launched trajectories via L1 and L2, as well as launch from an Earth-based elevator and subsequent rendezvous with lunar elevators placed either on the near or on the far side of the Moon. The benchmark figures by which the different transfer options are characterized and evaluated include release radius (RR), required delta v, transfer times as well as other factors such as accessibility of different lunar latitudes, frequency of launch opportunities and mission complexity. The performances of the different lunar transfer options are compared with each other as well as with the performance of conventional mission concepts, represented by Apollo. c2005 Elsevier Ltd. All rights reserved.

Lunar transportation scenarios utilising the Space Elevator

Science.gov (United States)

Engel, Kilian A.

2005-07-01

The Space Elevator (SE) concept has begun to receive an increasing amount of attention within the space community over the past couple of years and is no longer widely dismissed as pure science fiction. In light of the renewed interest in a, possibly sustained, human presence on the Moon and the fact that transportation and logistics form the bottleneck of many conceivable lunar missions, it is interesting to investigate what role the SE could eventually play in implementing an efficient Earth to Moon transportation system. The elevator allows vehicles to ascend from Earth and be injected into a trans-lunar trajectory without the use of chemical thrusters, thus eliminating gravity loss, aerodynamic loss and the need of high thrust multistage launch systems. Such a system therefore promises substantial savings of propellant and structural mass and could greatly increase the efficiency of Earth to Moon transportation. This paper analyzes different elevator-based trans-lunar transportation scenarios and characterizes them in terms of a number of benchmark figures. The transportation scenarios include direct elevator-launched trans-lunar trajectories, elevator-launched trajectories via L1 and L2, as well as launch from an Earth-based elevator and subsequent rendezvous with lunar elevators placed either on the near or on the far side of the Moon. The benchmark figures by which the different transfer options are characterized and evaluated include release radius (RR), required Δv, transfer times as well as other factors such as accessibility of different lunar latitudes, frequency of launch opportunities and mission complexity. The performances of the different lunar transfer options are compared with each other as well as with the performance of conventional mission concepts, represented by Apollo.

Aerospace News: Space Shuttle Commemoration. Volume 2, No. 7

Science.gov (United States)

2011-01-01

The complex space shuttle design was comprised of four components: the external tank, two solid rocket boosters (SRB), and the orbiter vehicle. Six orbiters were used during the life of the program. In order of introduction into the fleet, they were: Enterprise (a test vehicle), Columbia, Challenger, Discovery, Atlantis and Endeavour. The space shuttle had the unique ability to launch into orbit, perform on-orbit tasks, return to earth and land on a runway. It was an orbiting laboratory, International Space Station crew delivery and supply replenisher, satellite launcher and payload delivery vehicle, all in one. Except for the external tank, all components of the space shuttle were designed to be reusable for many flights. ATK s reusable solid rocket motors (RSRM) were designed to be flown, recovered, and the metal components reused 20 times. Following each space shuttle launch, the SRBs would parachute into the ocean and be recovered by the Liberty Star and Freedom Star recovery ships. The recovered boosters would then be received at the Cape Canaveral Air Force Station Hangar AF facility for disassembly and engineering post-flight evaluation. At Hangar AF, the RSRM field joints were demated and the segments prepared to be returned to Utah by railcar. The segments were then shipped to ATK s facilities in Clearfield for additional evaluation prior to washout, disassembly and refurbishment. Later the refurbished metal components would be transported to ATK s Promontory facilities to begin a new cycle. ATK s RSRMs were manufactured in Promontory, Utah. During the Space Shuttle Program, ATK supported NASA s Marshall Space Flight Center whose responsibility was for all propulsion elements on the program, including the main engines and solid rocket motors. On launch day for the space shuttle, ATK s Launch Site Operations employees at Kennedy Space Center (KSC) provided lead engineering support for ground operations and NASA s chief engineer. It was ATK s responsibility

Authoring Systems Delivering Reusable Learning Objects

Directory of Open Access Journals (Sweden)

George Nicola Sammour

2009-10-01

Full Text Available A three layer e-learning course development model has been defined based on a conceptual model of learning content object. It starts by decomposing the learning content into small chunks which are initially placed in a hierarchic structure of units and blocks. The raw content components, being the atomic learning objects (ALO, were linked to the blocks and are structured in the database. We set forward a dynamic generation of LO's using re-usable e-learning raw materials or ALO’s In that view we need a LO authoring/ assembling system fitting the requirements of interoperability and reusability and starting from selecting the raw learning content from the learning materials content database. In practice authoring systems are used to develop e-learning courses. The company EDUWEST has developed an authoring system that is database based and will be SCORM compliant in the near future.

RAGE Reusable Game Software Components and Their Integration into Serious Game Engines

NARCIS (Netherlands)

Van der Vegt, Wim; Nyamsuren, Enkhbold; Westera, Wim

2016-01-01

This paper presents and validates a methodology for integrating reusable software components in diverse game engines. While conforming to the RAGE com-ponent-based architecture described elsewhere, the paper explains how the interac-tions and data exchange processes between a reusable software

14 CFR 401.3 - The Associate Administrator for Commercial Space Transportation.

Science.gov (United States)

2010-01-01

... space transportation by the United States private sector. [Doc. No. FAA-2006-24197, 72 FR 17016, Apr. 6... AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION GENERAL ORGANIZATION AND DEFINITIONS § 401.3 The...

User community development for the space transportation system/Skylab

Science.gov (United States)

Archer, J. L.; Beauchamp, N. A.

1974-01-01

The New User Function plan for identifying beneficial uses of space is described. Critical issues such as funding, manpower, and protection of user proprietary rights are discussed along with common barriers which impede the development of a user community. Studies for developing methodologies of identifying new users and uses of the space transportation system are included.

New reusable elastomer electrodes for assessing body composition

International Nuclear Information System (INIS)

Moreno, M-V; Chaset, L; Bittner, P A; Barthod, C; Passard, M

2013-01-01

The development of telemedicine requires finding solutions of reusable electrodes for use in patients' homes. The objective of this study is to evaluate the relevance of reusable elastomer electrodes for measuring body composition. We measured a population of healthy Caucasian (n = 17). A measurement was made with a reference device, the Xitron®, associated with AgCl Gel electrodes (Gel) and another measurement with a multifrequency impedancemeter Z-Metrix® associated with reusable elastomer electrodes (Elast). We obtained a low variability with an average error of repeatability of 0.39% for Re and 0.32% for Rinf. There is a non significantly difference (P T-test > 0.1) about 200 ml between extracellular water Ve measured with Gel and Elast in supine and in standing position. For total body water Vt, we note a non significantly difference (P T-test > 0.1) about 100 ml and 2.2 1 respectively in supine and standing position. The results give low dispersion, with R 2 superior to 0.90, with a 1.5% maximal error between Gel and Elast on Ve in standing position. It looks possible, taking a few precautions, using elastomer electrodes for assessing body composition.

Reusable fuel test assembly for the FFTF

International Nuclear Information System (INIS)

Pitner, A.L.; Dittmer, J.O.

1992-01-01

A fuel test assembly that provides re-irradiation capability after interim discharge and reconstitution of the test pin bundle has been developed for use in the Fast Flux Test Facility (FFTF). This test vehicle permits irradiation test data to be obtained at multiple exposures on a few select test pins without the substantial expense of fabricating individual test assemblies as would otherwise be required. A variety of test pin types can be loaded in the reusable test assembly. A reusable test vehicle for irradiation testing in the FFTF has long been desired, but a number of obstacles previously prevented the implementation of such an experimental rig. The MFF-8A test assembly employs a 169-pin bundle using HT-9 alloy for duct and cladding material. The standard driver pins in the fuel bundle are sodium-bonded metal fuel (U-10 wt% Zr). Thirty-seven positions in the bundle are replaceable pin positions. Standard MFF-8A driver pins can be loaded in any test pin location to fill the bundle if necessary. Application of the MFF-8A reusable test assembly in the FFTF constitutes a considerable cost-saving measure with regard to irradiation testing. Only a few well-characterized test pins need be fabricated to conduct a test program rather than constructing entire test assemblies

Wound dressing with reusable electronics for wireless monitoring

KAUST Repository

Shamim, Atif

2016-10-20

A wound dressing device with reusable electronics for wireless monitoring and a method of making the same are provided. The device can be a smart device. In an embodiment, the device has a disposable portion including one or more sensors and a reusable portion including wireless electronics. The one or more sensors can be secured to a flexible substrate and can be printed by non-contact printing on the substrate. The disposable portion can be removably coupled to the one or more sensors. The device can include one or more sensors for wireless monitoring of a wound, a wound dressing, a body fluid exuded by the wound and/or wearer health.

NASA's Commercial Crew Program, The Next Step in U.S. Space Transportation

Science.gov (United States)

Mango, Edward J.; Thomas, Rayelle E.

2013-01-01

The Commercial Crew Program (CCP) is leading NASA's efforts to develop the next U.S. capability for crew transportation and rescue services to and from the International Space Station (ISS) by the mid-decade timeframe. The outcome of this capability is expected to stimulate and expand the U.S. space transportation industry. NASA is relying on its decades of human space flight experience to certify U.S. crewed vehicles to the ISS and is doing so in a two phase certification approach. NASA Certification will cover all aspects of a crew transportation system, including development, test, evaluation, and verification; program management and control; flight readiness certification; launch, landing, recovery, and mission operations; sustaining engineering and maintenance/upgrades. To ensure NASA crew safety, NASA Certification will validate technical and performance requirements, verify compliance with NASA requirements, validate the crew transportation system operates in appropriate environments, and quantify residual risks.

The YES2 Experience : Towards Sustainable Space Transportation using Tethers

NARCIS (Netherlands)

Van der Heide, E.J.; Kruijff, M.; Ockels, W.J.

2008-01-01

Today there is no common vision on sustainable space transportation. Rockets expel gasses and solid rockets often small particles. These have negative effect on the environment, but it is not understood to what extent. With ever growing demand for access to space, sustainable technology developments

Cost analysis of single-use (Ambu® aScope™) and reusable bronchoscopes in the ICU.

Science.gov (United States)

Perbet, S; Blanquet, M; Mourgues, C; Delmas, J; Bertran, S; Longère, B; Boïko-Alaux, V; Chennell, P; Bazin, J-E; Constantin, J-M

2017-12-01

Flexible optical bronchoscopes are essential for management of airways in ICU, but the conventional reusable flexible scopes have three major drawbacks: high cost of repairs, need for decontamination, and possible transmission of infectious agents. The main objective of this study was to measure the cost of bronchoalveolar lavage (BAL) and percutaneous tracheostomy (PT) using reusable bronchoscopes and single-use bronchoscopes in an ICU of an university hospital. The secondary objective was to compare the satisfaction of healthcare professionals with reusable and single-use bronchoscopes. The study was performed between August 2009 and July 2014 in a 16-bed ICU. All BAL and PT procedures were performed by experienced healthcare professionals. Cost analysis was performed considering ICU and hospital organization. Healthcare professional satisfaction with single-use and reusable scopes was determined based on eight factors. Sensitivity analysis was performed by applying discount rates (0, 3, and 5%) and by simulation of six situations based on different assumptions. At a discount rate of 3%, the costs per BAL for the two reusable scopes were 188.86€ (scope 1) and 185.94€ (scope 2), and the costs per PT for the reusable scope 1 and scope 2 and single-use scopes were 1613.84€, 410.24€, and 204.49€, respectively. The cost per procedure for the reusable scopes depended on the number of procedures performed, maintenance costs, and decontamination costs. Healthcare professionals were more satisfied with the third-generation single-use Ambu ® aScope™. The cost per procedure for the single-use scope was not superior to that for reusable scopes. The choice of single-use or reusable bronchoscopes in an ICU should consider the frequency of procedures and the number of bronchoscopes needed.

Transport, space and society in Copenhagen and Bogotá, 1940-2010

DEFF Research Database (Denmark)

Pineda, Andres Felipe Valderrama

This paper explores the way urban space, transportation networks and urban societies co-evolve and shape each other in time and how this process impacts the development of specific infrastructure projects in cities. To illustrate and analyse these processes, I examine the space design and transport...... as both the Metro and Transmilenio were promoted as high end means to move commuters out of their cars and into the public transport system. Based on the work of Ulrik Jørgensen, I propose that a city can be considered as an arena of development where different actor-networks interact and thus shape...... and are shaped by social processes such as the space development of the city, the enactment of certain discourse of self representation (cities as regional poles of development for instance) and the daily routines of city dwellers and their living choices, among others. This type of sociological analysis...

Deep Space Gateway "Recycler" Mission

Science.gov (United States)

Graham, L.; Fries, M.; Hamilton, J.; Landis, R.; John, K.; O'Hara, W.

2018-02-01

Use of the Deep Space Gateway provides a hub for a reusable planetary sample return vehicle for missions to gather star dust as well as samples from various parts of the solar system including main belt asteroids, near-Earth asteroids, and Mars moon.

Ventilation Transport Trade Study for Future Space Suit Life Support Systems

Science.gov (United States)

Kempf, Robert; Vogel, Matthew; Paul, Heather L.

2008-01-01

A new and advanced portable life support system (PLSS) for space suit surface exploration will require a durable, compact, and energy efficient system to transport the ventilation stream through the space suit. Current space suits used by NASA circulate the ventilation stream via a ball-bearing supported centrifugal fan. As NASA enters the design phase for the next generation PLSS, it is necessary to evaluate available technologies to determine what improvements can be made in mass, volume, power, and reliability for a ventilation transport system. Several air movement devices already designed for commercial, military, and space applications are optimized in these areas and could be adapted for EVA use. This paper summarizes the efforts to identify and compare the latest fan and bearing technologies to determine candidates for the next generation PLSS.

Space transportation main engine reliability and safety

Science.gov (United States)

Monk, Jan C.

1991-01-01

Viewgraphs are used to illustrate the reliability engineering and aerospace safety of the Space Transportation Main Engine (STME). A technology developed is called Total Quality Management (TQM). The goal is to develop a robust design. Reducing process variability produces a product with improved reliability and safety. Some engine system design characteristics are identified which improves reliability.

Magnetically-refreshable receptor platform structures for reusable nano-biosensor chips

International Nuclear Information System (INIS)

Yoo, Haneul; Cho, Dong-guk; Park, Juhun; Nam, Ki Wan; Cho, Young Tak; Chen, Xing; Hong, Seunghun; Lee, Dong Jun; Park, Jae Yeol

2016-01-01

We developed a magnetically-refreshable receptor platform structure which can be integrated with quite versatile nano-biosensor structures to build reusable nano-biosensor chips. This structure allows one to easily remove used receptor molecules from a biosensor surface and reuse the biosensor for repeated sensing operations. Using this structure, we demonstrated reusable immunofluorescence biosensors. Significantly, since our method allows one to place receptor molecules very close to a nano-biosensor surface, it can be utilized to build reusable carbon nanotube transistor-based biosensors which require receptor molecules within a Debye length from the sensor surface. Furthermore, we also show that a single sensor chip can be utilized to detect two different target molecules simply by replacing receptor molecules using our method. Since this method does not rely on any chemical reaction to refresh sensor chips, it can be utilized for versatile biosensor structures and virtually-general receptor molecular species. (paper)

A literature review on business process modelling: new frontiers of reusability

Science.gov (United States)

Aldin, Laden; de Cesare, Sergio

2011-08-01

Business process modelling (BPM) has become fundamental for modern enterprises due to the increasing rate of organisational change. As a consequence, business processes need to be continuously (re-)designed as well as subsequently aligned with the corresponding enterprise information systems. One major problem associated with the design of business processes is reusability. Reuse of business process models has the potential of increasing the efficiency and effectiveness of BPM. This article critically surveys the existing literature on the problem of BPM reusability and more specifically on that State-of-the-Art research that can provide or suggest the 'elements' required for the development of a methodology aimed at discovering reusable conceptual artefacts in the form of patterns. The article initially clarifies the definitions of business process and business process model; then, it sets out to explore the previous research conducted in areas that have an impact on reusability in BPM. The article concludes by distilling directions for future research towards the development of apatterns-based approach to BPM; an approach that brings together the contributions made by the research community in the areas of process mining and discovery, declarative approaches and ontologies.

75 FR 71791 - Commercial Space Transportation Advisory Committee-Public Teleconference

Science.gov (United States)

2010-11-24

... debris questions asked by the FAA; continuing the group's review of the Concept of Operation for Global Space Vehicle Debris Threat Management Report, and updating the list of top issues that should require... given of a teleconference of the Space Transportation Operations Working Group (STOWG) of the Commercial...

Microservices in Web Objects Enabled IoT Environment for Enhancing Reusability.

Science.gov (United States)

Jarwar, Muhammad Aslam; Kibria, Muhammad Golam; Ali, Sajjad; Chong, Ilyoung

2018-01-26

In the ubiquitous Internet of Things (IoT) environment, reusing objects instead of creating new one has become important in academics and industries. The situation becomes complex due to the availability of a huge number of connected IoT objects, and each individual service creates a new object instead of reusing the existing one to fulfill a requirement. A well-standard mechanism not only improves the reusability of objects but also improves service modularity and extensibility, and reduces cost. Web Objects enabled IoT environment applies the principle of reusability of objects in multiple IoT application domains through central objects repository and microservices. To reuse objects with microservices and to maintain a relationship with them, this study presents an architecture of Web of Objects platform. In the case of a similar request for an object, the already instantiated object that exists in the same or from other domain can be reused. Reuse of objects through microservices avoids duplications, and reduces time to search and instantiate them from their registries. Further, this article presents an algorithm for microservices and related objects discovery that considers the reusability of objects through the central objects repository. To support the reusability of objects, the necessary algorithm for objects matching is also presented. To realize the reusability of objects in Web Objects enabled IoT environment, a prototype has been designed and implemented based on a use case scenario. Finally, the results of the prototype have been analyzed and discussed to validate the proposed approach.

Microservices in Web Objects Enabled IoT Environment for Enhancing Reusability

Directory of Open Access Journals (Sweden)

Muhammad Aslam Jarwar

2018-01-01

Full Text Available In the ubiquitous Internet of Things (IoT environment, reusing objects instead of creating new one has become important in academics and industries. The situation becomes complex due to the availability of a huge number of connected IoT objects, and each individual service creates a new object instead of reusing the existing one to fulfill a requirement. A well-standard mechanism not only improves the reusability of objects but also improves service modularity and extensibility, and reduces cost. Web Objects enabled IoT environment applies the principle of reusability of objects in multiple IoT application domains through central objects repository and microservices. To reuse objects with microservices and to maintain a relationship with them, this study presents an architecture of Web of Objects platform. In the case of a similar request for an object, the already instantiated object that exists in the same or from other domain can be reused. Reuse of objects through microservices avoids duplications, and reduces time to search and instantiate them from their registries. Further, this article presents an algorithm for microservices and related objects discovery that considers the reusability of objects through the central objects repository. To support the reusability of objects, the necessary algorithm for objects matching is also presented. To realize the reusability of objects in Web Objects enabled IoT environment, a prototype has been designed and implemented based on a use case scenario. Finally, the results of the prototype have been analyzed and discussed to validate the proposed approach.

Reusable coordinator modules for massively concurrent applications

NARCIS (Netherlands)

F. Arbab (Farhad); C.L. Blom (Kees); F.J. Burger (Freek); C.T.H. Everaars (Kees)

1998-01-01

htmlabstractIsolating computation and communication concerns into separate pure computation and pure coordination modules enhances modularity, understandability and reusability of parallel and/or distributed software. MANIFOLD is a pure coordination language that encourages this separation. We use

Reusable Military Launch Systems (RMLS)

Science.gov (United States)

2008-02-01

shown in Figure 11. The second configuration is an axisymmetric, rocket-based combined cycle (RBCC) powered, SSTO vehicle, similar to the GTX...McCormick, D., and Sorensen, K., “Hyperion: An SSTO Vision Vehicle Concept Utilizing Rocket-Based Combined Cycle Propulsion”, AIAA paper 99-4944...there have been several failedattempts at the development of reusable rocket or air-breathing launch vehicle systems. Single-stage-to-orbit ( SSTO

Center for Space Transportation and Applied Research Fifth Annual Technical Symposium Proceedings

Science.gov (United States)

1993-01-01

This Fifth Annual Technical Symposium, sponsored by the UT-Calspan Center for Space Transportation and Applied Research (CSTAR), is organized to provide an overview of the technical accomplishments of the Center's five Research and Technology focus areas during the past year. These areas include chemical propulsion, electric propulsion, commerical space transportation, computational methods, and laser materials processing. Papers in the area of artificial intelligence/expert systems are also presented.

Reusable single-port access device shortens operative time and reduces operative costs.

Science.gov (United States)

Shussman, Noam; Kedar, Asaf; Elazary, Ram; Abu Gazala, Mahmoud; Rivkind, Avraham I; Mintz, Yoav

2014-06-01

In recent years, single-port laparoscopy (SPL) has become an attractive approach for performing surgical procedures. The pitfalls of this approach are technical and financial. Financial concerns are due to the increased cost of dedicated devices and prolonged operating room time. Our aim was to calculate the cost of SPL using a reusable port and instruments in order to evaluate the cost difference between this approach to SPL using the available disposable ports and standard laparoscopy. We performed 22 laparoscopic procedures via the SPL approach using a reusable single-port access system and reusable laparoscopic instruments. These included 17 cholecystectomies and five other procedures. Operative time, postoperative length of stay (LOS) and complications were prospectively recorded and were compared with similar data from our SPL database. Student's t test was used for statistical analysis. SPL was successfully performed in all cases. Mean operative time for cholecystectomy was 72 min (range 40-116). Postoperative LOS was not changed from our standard protocols and was 1.1 days for cholecystectomy. The postoperative course was within normal limits for all patients and perioperative morbidity was recorded. Both operative time and length of hospital stay were shorter for the 17 patients who underwent cholecystectomy using a reusable port than for the matched previous 17 SPL cholecystectomies we performed (p cost difference. Operating with a reusable port ended up with an average cost savings of US$388 compared with using disposable ports, and US$240 compared with standard laparoscopy. Single-port laparoscopic surgery is a technically challenging and expensive surgical approach. Financial concerns among others have been advocated against this approach; however, we demonstrate herein that using a reusable port and instruments reduces operative time and overall operative costs, even beyond the cost of standard laparoscopy.

Mars Conjunction Crewed Missions With a Reusable Hybrid Architecture

Science.gov (United States)

Merrill, Raymond G.; Strange, Nathan J.; Qu, Min; Hatten, Noble

2015-01-01

A new crew Mars architecture has been developed that provides many potential benefits for NASA-led human Mars moons and surface missions beginning in the 2030s or 2040s. By using both chemical and electric propulsion systems where they are most beneficial and maintaining as much orbital energy as possible, the Hybrid spaceship that carries crew round trip to Mars is pre-integrated before launch and can be delivered to orbit by a single launch. After check-out on the way to cis-lunar space, it is refueled and can travel round trip to Mars in less than 1100 days, with a minimum of 300 days in Mars vicinity (opportunity dependent). The entire spaceship is recaptured into cis-lunar space and can be reused. The spaceship consists of a habitat for 4 crew attached to the Hybrid propulsion stage which uses long duration electric and chemical in-space propulsion technologies that are in use today. The hybrid architecture's con-ops has no in-space assembly of the crew transfer vehicle and requires only rendezvous of crew in a highly elliptical Earth orbit for arrival at and departure from the spaceship. The crew transfer vehicle does not travel to Mars so it only needs be able to last in space for weeks and re-enter at lunar velocities. The spaceship can be refueled and resupplied for multiple trips to Mars (every other opportunity). The hybrid propulsion stage for crewed transits can also be utilized for cargo delivery to Mars every other opportunity in a reusable manner to pre-deploy infrastructure required for Mars vicinity operations. Finally, the Hybrid architecture provides evolution options for mitigating key long-duration space exploration risks, including crew microgravity and radiation exposure.

Learning Objects, Repositories, Sharing and Reusability

Science.gov (United States)

Koppi, Tony; Bogle, Lisa; Bogle, Mike

2005-01-01

The online Learning Resource Catalogue (LRC) Project has been part of an international consortium for several years and currently includes 25 institutions worldwide. The LRC Project has evolved for several pragmatic reasons into an academic network whereby members can identify and share reusable learning objects as well as collaborate in a number…

Reusable Solid Rocket Motor - Accomplishment, Lessons, and a Culture of Success

Science.gov (United States)

Moore, D. R.; Phelps, W. J.

2011-01-01

The Reusable Solid Rocket Motor (RSRM) represents the largest solid rocket motor (SRM) ever flown and the only human-rated solid motor. High reliability of the RSRM has been the result of challenges addressed and lessons learned. Advancements have resulted by applying attention to process control, testing, and postflight through timely and thorough communication in dealing with all issues. A structured and disciplined approach was taken to identify and disposition all concerns. Careful consideration and application of alternate opinions was embraced. Focus was placed on process control, ground test programs, and postflight assessment. Process control is mandatory for an SRM, because an acceptance test of the delivered product is not feasible. The RSRM maintained both full-scale and subscale test articles, which enabled continuous improvement of design and evaluation of process control and material behavior. Additionally RSRM reliability was achieved through attention to detail in post flight assessment to observe any shift in performance. The postflight analysis and inspections provided invaluable reliability data as it enables observation of actual flight performance, most of which would not be available if the motors were not recovered. RSRM reusability offered unique opportunities to learn about the hardware. NASA is moving forward with the Space Launch System that incorporates propulsion systems that takes advantage of the heritage Shuttle and Ares solid motor programs. These unique challenges, features of the RSRM, materials and manufacturing issues, and design improvements will be discussed in the paper.

Transforming existing content into reusable Learning Objects

NARCIS (Netherlands)

Doorten, Monique; Giesbers, Bas; Janssen, José; Daniels, Jan; Koper, Rob

2003-01-01

Please cite as: Doorten, M., Giesbers, B., Janssen, J., Daniëls, J, & Koper, E.J.R., (2004). Transforming existing content into reusable learning objects. In R. McGreal, Online Education using Learning Objects (pp. 116-127). London: RoutledgeFalmer.

Space Transportation Materials and Structures Technology Workshop. Volume 2: Proceedings

International Nuclear Information System (INIS)

Cazier, F.W. Jr.; Gardner, J.E.

1993-02-01

The Space Transportation Materials and Structures Technology Workshop was held on September 23-26, 1991, in Newport News, Virginia. The workshop, sponsored by the NASA Office of Space Flight and the NASA Office of Aeronautics and Space Technology, was held to provide a forum for communication within the space materials and structures technology developer and user communities. Workshop participants were organized into a Vehicle Technology Requirements session and three working panels: Materials and Structures Technologies for Vehicle Systems, Propulsion Systems, and Entry Systems. Separate abstracts have been prepared for papers in this report

Collaborative Approaches in Developing Environmental and Safety Management Systems for Commercial Space Transportation

Science.gov (United States)

Zee, Stacey; Murray, D.

2009-01-01

The Federal Aviation Administration (FAA), Office of Commercial Space Transportation (AST) licenses and permits U.S. commercial space launch and reentry activities, and licenses the operation of non-federal launch and reentry sites. ASTs mission is to ensure the protection of the public, property, and the national security and foreign policy interests of the United States during commercial space transportation activities and to encourage, facilitate, and promote U.S. commercial space transportation. AST faces unique challenges of ensuring the protection of public health and safety while facilitating and promoting U.S. commercial space transportation. AST has developed an Environmental Management System (EMS) and a Safety Management System (SMS) to help meet its mission. Although the EMS and SMS were developed independently, the systems share similar elements. Both systems follow a Plan-Do-Act-Check model in identifying potential environmental aspects or public safety hazards, assessing significance in terms of severity and likelihood of occurrence, developing approaches to reduce risk, and verifying that the risk is reduced. This paper will describe the similarities between ASTs EMS and SMS elements and how AST is building a collaborative approach in environmental and safety management to reduce impacts to the environment and risks to the public.

NASA space radiation transport code development consortium

International Nuclear Information System (INIS)

Townsend, L. W.

2005-01-01

Recently, NASA established a consortium involving the Univ. of Tennessee (lead institution), the Univ. of Houston, Roanoke College and various government and national laboratories, to accelerate the development of a standard set of radiation transport computer codes for NASA human exploration applications. This effort involves further improvements of the Monte Carlo codes HETC and FLUKA and the deterministic code HZETRN, including developing nuclear reaction databases necessary to extend the Monte Carlo codes to carry out heavy ion transport, and extending HZETRN to three dimensions. The improved codes will be validated by comparing predictions with measured laboratory transport data, provided by an experimental measurements consortium, and measurements in the upper atmosphere on the balloon-borne Deep Space Test Bed (DSTB). In this paper, we present an overview of the consortium members and the current status and future plans of consortium efforts to meet the research goals and objectives of this extensive undertaking. (authors)

14 CFR 431.23 - Policy review.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Policy review. 431.23 Section 431.23... TRANSPORTATION LICENSING LAUNCH AND REENTRY OF A REUSABLE LAUNCH VEHICLE (RLV) Policy Review and Approval for Launch and Reentry of a Reusable Launch Vehicle § 431.23 Policy review. (a) The FAA reviews an RLV...

Transport and matching of low energy space charge dominated beams

International Nuclear Information System (INIS)

Pandit, V.S.

2013-01-01

The transport and matching of low energy high intensity beams from the ion source to the subsequent accelerating structure are of considerable interest in recent years for variety of applications such as Accelerator driven system (ADSS), transmutation of nuclear waste, spallation neutron sources etc. It is essential to perform detailed simulations with experimentation to predict the beam evolution in the presence of nonlinear self as well as external fields before the design of the next accelerating structure is finalized. In order to study and settle various physics and technical issues related with transport of space charge dominated beams we have developed a 2.45 GHz microwave ion source at VECC which is now delivering more than 10 mA proton beam current at 80 keV. We have successfully transported well collimated 8 mA proton beam through the solenoid based 3 meter long transport line and studied various beam properties. We have also studied the transport of beam through spiral inflector at low beam current ∼ 1mA. In this article we will discuss the beam transport issues and describe a technique for simulation of beam envelopes in presence of linear space charge effects. We use canonical description of the motion of a single particle and then obtain first order differential equations for evolution of the moments of beam ensemble by assuming uniform distribution of the beam. We will also discuss the methodology used in the simulations to understand the observed beam behaviour during transport. (author)

Interfacial and Wall Transport Models for SPACE-CAP Code

International Nuclear Information System (INIS)

Hong, Soon Joon; Choo, Yeon Joon; Han, Tae Young; Hwang, Su Hyun; Lee, Byung Chul; Choi, Hoon; Ha, Sang Jun

2009-01-01

The development project for the domestic design code was launched to be used for the safety and performance analysis of pressurized light water reactors. And CAP (Containment Analysis Package) code has been also developed for the containment safety and performance analysis side by side with SPACE. The CAP code treats three fields (gas, continuous liquid, and dispersed drop) for the assessment of containment specific phenomena, and is featured by its multidimensional assessment capabilities. Thermal hydraulics solver was already developed and now under testing of its stability and soundness. As a next step, interfacial and wall transport models was setup. In order to develop the best model and correlation package for the CAP code, various models currently used in major containment analysis codes, which are GOTHIC, CONTAIN2.0, and CONTEMPT-LT, have been reviewed. The origins of the selected models used in these codes have also been examined to find out if the models have not conflict with a proprietary right. In addition, a literature survey of the recent studies has been performed in order to incorporate the better models for the CAP code. The models and correlations of SPACE were also reviewed. CAP models and correlations are composed of interfacial heat/mass, and momentum transport models, and wall heat/mass, and momentum transport models. This paper discusses on those transport models in the CAP code

Interfacial and Wall Transport Models for SPACE-CAP Code

Energy Technology Data Exchange (ETDEWEB)

Hong, Soon Joon; Choo, Yeon Joon; Han, Tae Young; Hwang, Su Hyun; Lee, Byung Chul [FNC Tech., Seoul (Korea, Republic of); Choi, Hoon; Ha, Sang Jun [Korea Electric Power Research Institute, Daejeon (Korea, Republic of)

2009-10-15

The development project for the domestic design code was launched to be used for the safety and performance analysis of pressurized light water reactors. And CAP (Containment Analysis Package) code has been also developed for the containment safety and performance analysis side by side with SPACE. The CAP code treats three fields (gas, continuous liquid, and dispersed drop) for the assessment of containment specific phenomena, and is featured by its multidimensional assessment capabilities. Thermal hydraulics solver was already developed and now under testing of its stability and soundness. As a next step, interfacial and wall transport models was setup. In order to develop the best model and correlation package for the CAP code, various models currently used in major containment analysis codes, which are GOTHIC, CONTAIN2.0, and CONTEMPT-LT, have been reviewed. The origins of the selected models used in these codes have also been examined to find out if the models have not conflict with a proprietary right. In addition, a literature survey of the recent studies has been performed in order to incorporate the better models for the CAP code. The models and correlations of SPACE were also reviewed. CAP models and correlations are composed of interfacial heat/mass, and momentum transport models, and wall heat/mass, and momentum transport models. This paper discusses on those transport models in the CAP code.

A revolutionary lunar space transportation system architecture using extraterrestrial LOX-augmented NTR propulsion

Science.gov (United States)

Borowski, Stanley K.; Corban, Robert R.; Culver, Donald W.; Bulman, Melvin J.; McIlwain, Mel C.

1994-08-01

The concept of a liquid oxygen (LOX)-augmented nuclear thermal rocket (NTR) engine is introduced, and its potential for revolutionizing lunar space transportation system (LTS) performance using extraterrestrial 'lunar-derived' liquid oxygen (LUNOX) is outlined. The LOX-augmented NTR (LANTR) represents the marriage of conventional liquid hydrogen (LH2)-cooled NTR and airbreathing engine technologies. The large divergent section of the NTR nozzle functions as an 'afterburner' into which oxygen is injected and supersonically combusted with nuclear preheated hydrogen emerging from the NTR's choked sonic throat: 'scramjet propulsion in reverse.' By varying the oxygen-to-fuel mixture ratio (MR), the LANTR concept can provide variable thrust and specific impulse (Isp) capability with a LH2-cooled NTR operating at relatively constant power output. For example, at a MR = 3, the thrust per engine can be increased by a factor of 2.75 while the Isp decreases by only 30 percent. With this thrust augmentation option, smaller, 'easier to develop' NTR's become more acceptable from a mission performance standpoint (e.g., earth escape gravity losses are reduced and perigee propulsion requirements are eliminated). Hydrogen mass and volume is also reduced resulting in smaller space vehicles. An evolutionary NTR-based lunar architecture requiring only Shuttle C and/or 'in-line' shuttle-derived launch vehicles (SDV's) would operate initially in an 'expandable mode' with NTR lunar transfer vehicles (LTV's) delivering 80 percent more payload on piloted missions than their LOX/LH2 chemical propulsion counterparts. With the establishment of LUNOX production facilities on the lunar surface and 'fuel/oxidizer' depot in low lunar orbit (LLO), monopropellant NTR's would be outfitted with an oxygen propellant module, feed system, and afterburner nozzle for 'bipropellant' operation. The LANTR cislunar LTV now transitions to a reusable mode with smaller vehicle and payload doubling benefits on

A Cis-Lunar Propellant Infrastructure for Flexible Path Exploration and Space Commerce

Science.gov (United States)

Oeftering, Richard C.

2012-01-01

This paper describes a space infrastructure concept that exploits lunar water for propellant production and delivers it to users in cis-lunar space. The goal is to provide responsive economical space transportation to destinations beyond low Earth orbit (LEO) and enable in-space commerce. This is a game changing concept that could fundamentally affect future space operations, provide greater access to space beyond LEO, and broaden participation in space exploration. The challenge is to minimize infrastructure development cost while achieving a low operational cost. This study discusses the evolutionary development of the infrastructure from a very modest robotic operation to one that is capable of supporting human operations. The cis-lunar infrastructure involves a mix of technologies including cryogenic propellant production, reusable lunar landers, propellant tankers, orbital transfer vehicles, aerobraking technologies, and electric propulsion. This cislunar propellant infrastructure replaces Earth-launched propellants for missions beyond LEO. It enables users to reach destinations with smaller launchers or effectively multiplies the user s existing payload capacity. Users can exploit the expanded capacity to launch logistics material that can then be traded with the infrastructure for propellants. This mutually beneficial trade between the cis-lunar infrastructure and propellant users forms the basis of in-space commerce.

Generalized free-space diffuse photon transport model based on the influence analysis of a camera lens diaphragm.

Science.gov (United States)

Chen, Xueli; Gao, Xinbo; Qu, Xiaochao; Chen, Duofang; Ma, Xiaopeng; Liang, Jimin; Tian, Jie

2010-10-10

The camera lens diaphragm is an important component in a noncontact optical imaging system and has a crucial influence on the images registered on the CCD camera. However, this influence has not been taken into account in the existing free-space photon transport models. To model the photon transport process more accurately, a generalized free-space photon transport model is proposed. It combines Lambertian source theory with analysis of the influence of the camera lens diaphragm to simulate photon transport process in free space. In addition, the radiance theorem is also adopted to establish the energy relationship between the virtual detector and the CCD camera. The accuracy and feasibility of the proposed model is validated with a Monte-Carlo-based free-space photon transport model and physical phantom experiment. A comparison study with our previous hybrid radiosity-radiance theorem based model demonstrates the improvement performance and potential of the proposed model for simulating photon transport process in free space.

Heavy-ion transport codes for radiotherapy and radioprotection in space

International Nuclear Information System (INIS)

Mancusi, Davide

2006-06-01

Simulation of the transport of heavy ions in matter is a field of nuclear science that has recently received attention in view of its importance for some relevant applications. Accelerated heavy ions can, for example, be used to treat cancers (heavy-ion radiotherapy) and show some superior qualities with respect to more conventional treatment systems, like photons (x-rays) or protons. Furthermore, long-term manned space missions (like a possible future mission to Mars) pose the challenge to protect astronauts and equipment on board against the harmful space radiation environment, where heavy ions can be responsible for a significant share of the exposure risk. The high accuracy expected from a transport algorithm (especially in the case of radiotherapy) and the large amount of semi-empirical knowledge necessary to even state the transport problem properly rule out any analytical approach; the alternative is to resort to numerical simulations in order to build treatment-planning systems for cancer or to aid space engineers in shielding design. This thesis is focused on the description of HIBRAC, a one-dimensional deterministic code optimised for radiotherapy, and PHITS (Particle and Heavy- Ion Transport System), a general-purpose three-dimensional Monte-Carlo code. The structure of both codes is outlined and some relevant results are presented. In the case of PHITS, we also report the first results of an ongoing comprehensive benchmarking program for the main components of the code; we present the comparison of partial charge-changing cross sections for a 400 MeV/n 40 Ar beam impinging on carbon, polyethylene, aluminium, copper, tin and lead targets

Life Cycle Assessment and Costing Methods for Device Procurement: Comparing Reusable and Single-Use Disposable Laryngoscopes.

Science.gov (United States)

Sherman, Jodi D; Raibley, Lewis A; Eckelman, Matthew J

2018-01-09

Traditional medical device procurement criteria include efficacy and safety, ease of use and handling, and procurement costs. However, little information is available about life cycle environmental impacts of the production, use, and disposal of medical devices, or about costs incurred after purchase. Reusable and disposable laryngoscopes are of current interest to anesthesiologists. Facing mounting pressure to quickly meet or exceed conflicting infection prevention guidelines and oversight body recommendations, many institutions may be electively switching to single-use disposable (SUD) rigid laryngoscopes or overcleaning reusables, potentially increasing both costs and waste generation. This study provides quantitative comparisons of environmental impacts and total cost of ownership among laryngoscope options, which can aid procurement decision making to benefit facilities and public health. We describe cradle-to-grave life cycle assessment (LCA) and life cycle costing (LCC) methods and apply these to reusable and SUD metal and plastic laryngoscope handles and tongue blade alternatives at Yale-New Haven Hospital (YNHH). The US Environmental Protection Agency's Tool for the Reduction and Assessment of Chemical and other environmental Impacts (TRACI) life cycle impact assessment method was used to model environmental impacts of greenhouse gases and other pollutant emissions. The SUD plastic handle generates an estimated 16-18 times more life cycle carbon dioxide equivalents (CO2-eq) than traditional low-level disinfection of the reusable steel handle. The SUD plastic tongue blade generates an estimated 5-6 times more CO2-eq than the reusable steel blade treated with high-level disinfection. SUD metal components generated much higher emissions than all alternatives. Both the SUD handle and SUD blade increased life cycle costs compared to the various reusable cleaning scenarios at YNHH. When extrapolated over 1 year (60,000 intubations), estimated costs increased

Design, Analysis and Qualification of Elevon for Reusable Launch Vehicle

Science.gov (United States)

Tiwari, S. B.; Suresh, R.; Krishnadasan, C. K.

2017-12-01

Reusable launch vehicle technology demonstrator is configured as a winged body vehicle, designed to fly in hypersonic, supersonic and subsonic regimes. The vehicle will be boosted to hypersonic speeds after which the winged body separates and descends using aerodynamic control. The aerodynamic control is achieved using the control surfaces mainly the rudder and the elevon. Elevons are deflected for pitch and roll control of the vehicle at various flight conditions. Elevons are subjected to aerodynamic, thermal and inertial loads during the flight. This paper gives details about the configuration, design, qualification and flight validation of elevon for Reusable Launch Vehicle.

The influence of lunar propellant production on the cost-effectiveness of cislunar transportation systems

Science.gov (United States)

Koelle, H. H.

1992-01-01

It is well known that propellants produced at the points of destination such as the Moon or Mars will help the economy of space transportation, particularly if round trips with a crew are involved. The construction and operation of a lunar base shortly after the turn of the century is one of the space programs under serious consideration at the present time. Space transportation is one of the major cost drivers. With present technology, if expendable launchers were employed, the specific transportation costs of one-way cargo flights would be approximately 10,000 dollars/kg (1985) at life-cycle cumulative 100,000 ton payload to the lunar surface. A fully reusable space transportation system using lunar oxygen and Earth-produced liquid hydrogen (LH2) would reduce the specific transportation costs by one order of magnitude to less than 1000 dollars/kg at the same payload volume. Another case of primary interest is the delivery of construction material and consumables from the lunar surface to the assembly site of space solar power plants in geostationary orbit (GEO). If such a system were technically and economically feasible, a cumulative payload of about 1 million tons or more would be required. At this level a space freighter system could deliver this material from Earth for about 300 dollars/kg (1985) to GEO. A lunar space transportation system using lunar oxygen and a fuel mixture of 50 percent Al and 50 percent LH2 (that has to come from Earth) could reduce the specific transportation costs to less than half, approximately 150 dollars/kg. If only lunar oxygen were available, these costs would come down to 200 dollars/kg. This analysis indicates a sizable reduction of the transportation burden on this type of mission. It should not be overlooked, however, that there are several uncertainties in such calculations. It is quite difficult at this point to calculate the cost of lunar-produced O and/or Al. This will be a function of production rate and life

Omicron space habitat—research stage II

Science.gov (United States)

Doule, Ondřej; Šálený, Vratislav; Hérin, Benoît; Rousek, Tomáš

2012-01-01

The design presented in this paper is in response to the revolution in private space activities, the increasing public interest in commercial flights to space and the utilization of structures such as space hotels or private orbital habitats. The baseline for the Omicron design concept is the Russian Salyut derived space station module. Salyut was the first space station to orbit the Earth. Its unique design and technical features were what made the development of space stations Salyut 1-7, MIR and the International Space Station (ISS) Zwezda service module possible. Due to its versatility and the reliable operating launch vehicle Proton, this space module series has the potential to be adapted for space hotel development. This paper proposes a conceptual design of the space habitat called Omicron, with particular focus on interior design for the microgravity environment. The Omicron concepts address the needs of space tourism with a strong emphasis on the safety and comfort of the spaceflight participants. The Omicron habitat supports three inhabitants in nominal conditions (e.g., two passengers and one astronaut). The habitat provides a flexible interior, facilities and spaces dynamically transforming in order to accommodate various types of activities, which will be performed in an organically formed interior supporting spatial orientation and movement in microgravity. The future development potential of Omicron is also considered. The baseline version is composed solely of one rigid module with an inverted cupola for observations. An alternative version offers more space using an inflatable structure. Finally, a combination of multiple Omicron modules enables the creation of a larger orbital habitat. The Omicron's subsystems support a few days visit by trained passengers. The transport to the habitat would be provided e.g., by the Soyuz TMA spacecraft carried by the Soyuz launch vehicle in the early stage of Omicron's development, before a fully reusable

Open-Source RTOS Space Qualification: An RTEMS Case Study

Science.gov (United States)

Zemerick, Scott

2017-01-01

NASA space-qualification of reusable off-the-shelf real-time operating systems (RTOSs) remains elusive due to several factors notably (1) The diverse nature of RTOSs utilized across NASA, (2) No single NASA space-qualification criteria, lack of verification and validation (V&V) analysis, or test beds, and (3) different RTOS heritages, specifically open-source RTOSs and closed vendor-provided RTOSs. As a leader in simulation test beds, the NASA IV&V Program is poised to help jump-start and lead the space-qualification effort of the open source Real-Time Executive for Multiprocessor Systems (RTEMS) RTOS. RTEMS, as a case-study, can be utilized as an example of how to qualify all RTOSs, particularly the reusable non-commercial (open-source) ones that are gaining usage and popularity across NASA. Qualification will improve the overall safety and mission assurance of RTOSs for NASA-agency wide usage. NASA's involvement in space-qualification of an open-source RTOS such as RTEMS will drive the RTOS industry toward a more qualified and mature open-source RTOS product.

Space station evolution: Planning for the future

Science.gov (United States)

Diaz, Alphonso V.; Askins, Barbara S.

1987-06-01

The need for permanently manned presence in space has been recognized by the United States and its international partners for many years. The development of this capability was delayed due to the concurrent recognition that reusable earth-to-orbit transportation was also needed and should be developed first. While the decision to go ahead with a permanently manned Space Station was on hold, requirements for the use of the Station were accumulating as ground-based research and the data from unmanned spacecraft sparked the imagination of both scientists and entrepreneurs. Thus, by the time of the Space Station implementation decision in the early 1980's, a variety of disciplines, with a variety of requirements, needed to be accommodated on one Space Station. Additional future requirements could be forecast for advanced missions that were still in the early planning stages. The logical response was the development of a multi-purpose Space Station with the ability to evolve on-orbit to new capabilities as required by user needs and national or international decisions, i.e., to build an evolutionary Space Station. Planning for evolution is conducted in parallel with the design and development of the baseline Space Station. Evolution planning is a strategic management process to facilitate change and protect future decisions. The objective is not to forecast the future, but to understand the future options and the implications of these on today's decisions. The major actions required now are: (1) the incorporation of evolution provisions (hooks and scars) in the baseline Space Station; and (2) the initiation of an evolution advanced development program.

Space station evolution: Planning for the future

Science.gov (United States)

Diaz, Alphonso V.; Askins, Barbara S.

1987-01-01

The need for permanently manned presence in space has been recognized by the United States and its international partners for many years. The development of this capability was delayed due to the concurrent recognition that reusable earth-to-orbit transportation was also needed and should be developed first. While the decision to go ahead with a permanently manned Space Station was on hold, requirements for the use of the Station were accumulating as ground-based research and the data from unmanned spacecraft sparked the imagination of both scientists and entrepreneurs. Thus, by the time of the Space Station implementation decision in the early 1980's, a variety of disciplines, with a variety of requirements, needed to be accommodated on one Space Station. Additional future requirements could be forecast for advanced missions that were still in the early planning stages. The logical response was the development of a multi-purpose Space Station with the ability to evolve on-orbit to new capabilities as required by user needs and national or international decisions, i.e., to build an evolutionary Space Station. Planning for evolution is conducted in parallel with the design and development of the baseline Space Station. Evolution planning is a strategic management process to facilitate change and protect future decisions. The objective is not to forecast the future, but to understand the future options and the implications of these on today's decisions. The major actions required now are: (1) the incorporation of evolution provisions (hooks and scars) in the baseline Space Station; and (2) the initiation of an evolution advanced development program.

Characterization of cement-based materials using a reusable piezoelectric impedance-based sensor

Science.gov (United States)

Tawie, R.; Lee, H. K.

2011-08-01

This paper proposes a reusable sensor, which employs a piezoceramic (PZT) plate as an active sensing transducer, for non-destructive monitoring of cement-based materials based on the electromechanical impedance (EMI) sensing technique. The advantage of the sensor design is that the PZT can be easily removed from the set-up and re-used for repetitive tests. The applicability of the sensor was demonstrated for monitoring of the setting of cement mortar. EMI measurements were performed using an impedance analyzer and the transformation of the specimen from the plastic to solid state was monitored by automatically measuring the changes in the PZT conductance spectra with respect to curing time using the root mean square deviation (RMSD) algorithm. In another experiment, drying-induced moisture loss of a hardened mortar specimen at saturated surface dry (SSD) condition was measured, and monitored using the reusable sensor to establish a correlation between the RMSD values and moisture loss rate. The reusable sensor was also demonstrated for detecting progressive damages imparted on a mortar specimen attached with the sensor under several loading levels before allowing it to load to failure. Overall, the reusable sensor is an effective and efficient monitoring device that could possibly be used for field application in characterization of cement-based materials.

Characterization of cement-based materials using a reusable piezoelectric impedance-based sensor

International Nuclear Information System (INIS)

Tawie, R; Lee, H K

2011-01-01

This paper proposes a reusable sensor, which employs a piezoceramic (PZT) plate as an active sensing transducer, for non-destructive monitoring of cement-based materials based on the electromechanical impedance (EMI) sensing technique. The advantage of the sensor design is that the PZT can be easily removed from the set-up and re-used for repetitive tests. The applicability of the sensor was demonstrated for monitoring of the setting of cement mortar. EMI measurements were performed using an impedance analyzer and the transformation of the specimen from the plastic to solid state was monitored by automatically measuring the changes in the PZT conductance spectra with respect to curing time using the root mean square deviation (RMSD) algorithm. In another experiment, drying-induced moisture loss of a hardened mortar specimen at saturated surface dry (SSD) condition was measured, and monitored using the reusable sensor to establish a correlation between the RMSD values and moisture loss rate. The reusable sensor was also demonstrated for detecting progressive damages imparted on a mortar specimen attached with the sensor under several loading levels before allowing it to load to failure. Overall, the reusable sensor is an effective and efficient monitoring device that could possibly be used for field application in characterization of cement-based materials

Commercial Space Transportation and Approaches to landing sites over Maritime Areas

OpenAIRE

Morlang, Frank; Hampe, Jens; Kaltenhäuser, Sven; Schmitt, Dirk-Roger

2015-01-01

Commercial Space Transportation becomes an international business and requires landing opportunities all over the world. Hence the integration of space vehicles in other airspace than the US NAS is an important topic to be considered. The Single European Sky ATM Research Programme (SESAR) is preparing the implementation of a new ATM system in Europe. The requirements are defined by the concept of the shared Business Trajectory and System Wide Information Management (SWIM). Space vehicle op...

Clinical outcomes and costs of reusable and single-use flexible ureterorenoscopes: a prospective cohort study.

Science.gov (United States)

Mager, R; Kurosch, M; Höfner, T; Frees, S; Haferkamp, A; Neisius, A

2018-01-22

The purpose of this study is to analyze clinical outcomes and costs of single-use flexible ureterorenoscopes in comparison with reusable flexible ureterorenoscopes in a tertiary referral center. Prospectively, 68 flexible ureterorenoscopies utilizing reusable (Flex-X2S, Flex-X C , Karl Storz) and 68 applying single-use flexible ureterorenoscopes (LithoVue, Boston Scientific) were collected. Clinical outcome parameters such as overall success rate, complication rates according to Clavien-Dindo, operation time and radiation exposure time were measured. Cost analysis was based on purchase costs and recurrent costs for repair and reprocessing divided by number of procedures. In each group 68 procedures were available for evaluation. In 91% of reusable and 88% of single-use ureterorenoscopies stone disease was treated with a mean stone burden of 101 ± 226 and 90 ± 244 mm 2 and lower pole involvement in 47 and 41%, respectively (p > 0.05). Comparing clinical outcomes of reusable vs. single-use instruments revealed no significant difference for overall success rates (81 vs. 87%), stone-free rates (82 vs. 85%), operation time (76.2 ± 46.8 vs. 76.8 ± 40.2 min), radiation exposure time (3.83 ± 3.15 vs. 3.93 ± 4.43 min) and complication rates (7 vs. 17%) (p > 0.05). A wide range of repair and purchase costs resulted in total to $1212-$1743 per procedure for reusable ureterorenoscopy whereas price of single-use ureterorenoscopy was $1300-$3180 per procedure. The current work provided evidence for equal clinical effectiveness of reusable and single-use flexible ureterorenoscopes. Partially overlapping ranges of costs for single-use and reusable scopes stress the importance to precisely know the expenses and caseload when negotiating purchase prices, repair prices and warranty conditions.

14 CFR 431.83 - Compliance monitoring.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Compliance monitoring. 431.83 Section 431.83 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... Requirements-Reusable Launch Vehicle Mission License Terms and Conditions § 431.83 Compliance monitoring. A...

Heavy-ion transport codes for radiotherapy and radioprotection in space

Energy Technology Data Exchange (ETDEWEB)

Mancusi, Davide

2006-06-15

Simulation of the transport of heavy ions in matter is a field of nuclear science that has recently received attention in view of its importance for some relevant applications. Accelerated heavy ions can, for example, be used to treat cancers (heavy-ion radiotherapy) and show some superior qualities with respect to more conventional treatment systems, like photons (x-rays) or protons. Furthermore, long-term manned space missions (like a possible future mission to Mars) pose the challenge to protect astronauts and equipment on board against the harmful space radiation environment, where heavy ions can be responsible for a significant share of the exposure risk. The high accuracy expected from a transport algorithm (especially in the case of radiotherapy) and the large amount of semi-empirical knowledge necessary to even state the transport problem properly rule out any analytical approach; the alternative is to resort to numerical simulations in order to build treatment-planning systems for cancer or to aid space engineers in shielding design. This thesis is focused on the description of HIBRAC, a one-dimensional deterministic code optimised for radiotherapy, and PHITS (Particle and Heavy- Ion Transport System), a general-purpose three-dimensional Monte-Carlo code. The structure of both codes is outlined and some relevant results are presented. In the case of PHITS, we also report the first results of an ongoing comprehensive benchmarking program for the main components of the code; we present the comparison of partial charge-changing cross sections for a 400 MeV/n {sup 40}Ar beam impinging on carbon, polyethylene, aluminium, copper, tin and lead targets.

On the economics of staging for reusable launch vehicles

Science.gov (United States)

Griffin, Michael D.; Claybaugh, William R.

1996-03-01

There has been much recent discussion concerning possible replacement systems for the current U.S. fleet of launch vehicles, including both the shuttle and expendable vehicles. Attention has been focused upon the feasibility and potential benefits of reusable single-stage-to-orbit (SSTO) launch systems for future access to low Earth orbit (LEO). In this paper we assume the technical feasibility of such vehicles, as well as the benefits to be derived from system reusability. We then consider the benefits of launch vehicle staging from the perspective of economic advantage rather than performance necessity. Conditions are derived under which two-stage-to-orbit (TSTO) launch systems, utilizing SSTO-class vehicle technology, offer a relative economic advantage for access to LEO.

Decomposition of business process models into reusable sub-diagrams

Directory of Open Access Journals (Sweden)

Wiśniewski Piotr

2017-01-01

Full Text Available In this paper, an approach to automatic decomposition of business process models is proposed. According to our method, an existing BPMN diagram is disassembled into reusable parts containing the desired number of elements. Such elements and structure can work as design patterns and be validated by a user in terms of correctness. In the next step, these component models are categorised considering their parameters such as resources used, as well as input and output data. The classified components may be considered a repository of reusable parts, that can be further applied in the design of new models. The proposed technique may play a significant role in facilitating the business process redesign procedure, which is of a great importance regarding engineering and industrial applications.

Macro Level Simulation Model Of Space Shuttle Processing

Science.gov (United States)

2000-01-01

The contents include: 1) Space Shuttle Processing Simulation Model; 2) Knowledge Acquisition; 3) Simulation Input Analysis; 4) Model Applications in Current Shuttle Environment; and 5) Model Applications for Future Reusable Launch Vehicles (RLV's). This paper is presented in viewgraph form.

Wound dressing with reusable electronics for wireless monitoring

KAUST Repository

Shamim, Atif; Farooqui, Muhammad Fahad

2016-01-01

A wound dressing device with reusable electronics for wireless monitoring and a method of making the same are provided. The device can be a smart device. In an embodiment, the device has a disposable portion including one or more sensors and a

Logistics: An integral part of cost efficient space operations

Science.gov (United States)

Montgomery, Ann D.

1996-01-01

The logistics of space programs and its history within NASA are discussed, with emphasis on manned space flight and the Space Shuttle program. The lessons learned and the experience gained during these programs are reported on. Key elements of logistics are highlighted, and the problems and issues that can be expected to arise in relation to the support of long-term space operations and future space programs, are discussed. Such missions include the International Space Station program and the reusable launch vehicle. Possible solutions to the problems identified are outlined.

En Route Care in Confined Spaces: Impact of Transport, Immobilization Practices, Space Constraints, and Medical Awareness Enhancements

Science.gov (United States)

2017-10-01

physical space , ergonomics , and enhancement of medical awareness. Outcomes of the project will provide significant information and tools that can be...This group of research projects was designed to look at various aspects of transport, immobilization, optimal physical space , ergonomics , and...Devereux, J. 2002. The nature of work -related neck and upper limb musculoskeletal disorders. Applied Ergonomics . 33(3): 207-17. Chaffin, D.B

A One Chip Hardened Solution for High Speed SpaceWire System Implementations. Session: Components

Science.gov (United States)

Marshall, Joseph R.; Berger, Richard W.; Rakow, Glenn P.

2007-01-01

An Application Specific Integrated Circuit (ASIC) that implements the SpaceWire protocol has been developed in a radiation hardened 0.25 micron CMOS technology. This effort began in March 2003 as a joint development between the NASA Goddard Space Flight Center (GSFC) and BAE Systems. The BAE Systems SpaceWire ASIC is comprised entirely of reusable core elements, many of which are already flight-proven. It incorporates a router with 4 SpaceWire ports and two local ports, dual PC1 bus interfaces, a microcontroller, 32KB of internal memory, and a memory controller for additional external memory use. The SpaceWire cores are also reused in other ASICs under development. The SpaceWire ASIC is planned for use on the Geostationary Operational Environmental Satellites (GOES)-R, the Lunar Reconnaissance Orbiter (LRO) and other missions. Engineering and flight parts have been delivered to programs and users. This paper reviews the SpaceWire protocol and those elements of it that have been built into the current and next SpaceWire reusable cores and features within the core that go beyond the current standard and can be enabled or disabled by the user. The adaptation of SpaceWire to BAE Systems' On Chip Bus (OCB) for compatibility with the other reusable cores will be reviewed and highlighted. Optional configurations within user systems and test boards will be shown. The physical implementation of the design will be described and test results from the hardware will be discussed. Application of this ASIC and other ASICs containing the SpaceWire cores and embedded microcontroller to Plug and Play and reconfigurable implementations will be described. Finally, the BAE Systems roadmap for SpaceWire developments will be updated, including some products already in design as well as longer term plans.

Transportable Applications Environment (TAE) Plus - A NASA productivity tool used to develop graphical user interfaces

Science.gov (United States)

Szczur, Martha R.

1991-01-01

The Transportable Applications Environment (TAE) Plus, developed at NASA's Goddard Space Flight Center, is an advanced portable user interface development environment which simplifies the process of creating and managing complex application graphical user interfaces (GUIs), supports prototyping, allows applications to be oported easily between different platforms, and encourages appropriate levels of user interface consistency between applications. This paper discusses the capabilities of the TAE Plus tool, and how it makes the job of designing and developing GUIs easier for the application developers. The paper also explains how tools like TAE Plus provide for reusability and ensure reliability of UI software components, as well as how they aid in the reduction of development and maintenance costs.

Monoenergetic neutral particle transport in an anisotropically scattering half-space

International Nuclear Information System (INIS)

Ganapol, B.D.; Garth, J.C.; Woolf, S.

1995-01-01

During the past several years, a considerable effort has been underway to develop reliable analytical benchmark solutions to the one-speed transport equation in various geometries. The reader may well ask open-quotes whyclose quotes such a task has been undertaken, given the recent rapid advances in numerical transport theory. The simple answer is that reliable numerical solutions do not yet exist, and their development still represents a mathematical challenge. However, regardless of how mathematically challenging the development is, there are more compelling reasons for this effort which are rooted in the very fundamentals of science and technology. In particular, these solutions, which are highly accurate numerical evaluations of analytical solution representations, serve as open-quotes industry standardsclose quotes to which other more approximate methods or approximations can be compared. Thus analytical benchmarks are part of the process control and continuous improvement of numerical transport methods and are therefore integral components in TQM (Total Quality Management) as applied to transport methods development. With the above reasoning in mind, the authors begin the development and application of a new analytical solution and evaluation for a half-space featuring anisotropic scattering. This work is an extension of previous efforts in which isotropically scattering half-spaces were treated. The previous benchmarks were obtained most conveniently via a numerical Laplace transform inversion which could be applied in a straightforward manner to the case of isotropic scattering. The application of the Laplace transform method is problematical for anisotropic scattering and does not admit to the direct identification of the scalar flux from integral transport theory

Update of KSC activities for the space transportation system

Science.gov (United States)

Gray, R. H.

1979-01-01

The paper is a status report on the facilities and planned operations at the Kennedy Space Center (KSC) that will support Space Shuttle launches. The conversion of KSC facilities to support efficient and economical checkout and launch operations in the era of the Space Shuttle is nearing completion. The driving force behind the KSC effort has been the necessity of providing adequate and indispensable facilities and support systems at minimum cost. This required the optimum utilization of existing buildings, equipment and systems, both at KSC and at Air Force property on Cape Canaveral, as well as the construction of two major new facilities and several minor ones. The entirely new structures discussed are the Shuttle Landing Facility and Orbiter Processing Facility. KSC stands ready to provide the rapid reliable economical landing-to-launch processing needed to ensure the success of this new space transportation system.

In-Space Repair and Refurbishment of Thermal Protection System Structures for Reusable Launch Vehicles

Science.gov (United States)

Singh, M.

2007-01-01

Advanced repair and refurbishment technologies are critically needed for the thermal protection system of current space transportation systems as well as for future launch and crew return vehicles. There is a history of damage to these systems from impact during ground handling or ice during launch. In addition, there exists the potential for in-orbit damage from micrometeoroid and orbital debris impact as well as different factors (weather, launch acoustics, shearing, etc.) during launch and re-entry. The GRC developed GRABER (Glenn Refractory Adhesive for Bonding and Exterior Repair) material has shown multiuse capability for repair of small cracks and damage in reinforced carbon-carbon (RCC) material. The concept consists of preparing an adhesive paste of desired ceramic with appropriate additives and then applying the paste to the damaged/cracked area of the RCC composites with an adhesive delivery system. The adhesive paste cures at 100-120 C and transforms into a high temperature ceramic during reentry conditions. A number of plasma torch and ArcJet tests were carried out to evaluate the crack repair capability of GRABER materials for Reinforced Carbon-Carbon (RCC) composites. For the large area repair applications, Integrated Systems for Tile and Leading Edge Repair (InSTALER) have been developed and evaluated under various ArcJet testing conditions. In this presentation, performance of the repair materials as applied to RCC is discussed. Additionally, critical in-space repair needs and technical challenges are reviewed.

Structures of the fractional spaces generated by the difference neutron transport operator

International Nuclear Information System (INIS)

Ashyralyev, Allaberen; Taskin, Abdulgafur

2015-01-01

The initial boundary value problem for the neutron transport equation is considered. The first, second and third order of accuracy difference schemes for the approximate solution of this problem are presented. Highly accurate difference schemes for neutron transport equation based on Padé approximation are constructed. In applications, stability estimates for solutions of difference schemes for the approximate solution of the neutron transport equation are obtained.The positivity of the neutron transport operator in Slobodeckij spaces is proved. Numerical techniques are developed and algorithms are tested on an example in MATLAB

PATH: a lumped-element beam-transport simulation program with space charge

International Nuclear Information System (INIS)

Farrell, J.A.

1983-01-01

PATH is a group of computer programs for simulating charged-particle beam-transport systems. It was developed for evaluating the effects of some aberrations without a time-consuming integration of trajectories through the system. The beam-transport portion of PATH is derived from the well-known program, DECAY TURTLE. PATH contains all features available in DECAY TURTLE (including the input format) plus additional features such as a more flexible random-ray generator, longitudinal phase space, some additional beamline elements, and space-charge routines. One of the programs also provides a simulation of an Alvarez linear accelerator. The programs, originally written for a CDC 7600 computer system, also are available on a VAX-VMS system. All of the programs are interactive with input prompting for ease of use

Space Transportation System Availability Relationships to Life Cycle Cost

Science.gov (United States)

Rhodes, Russel E.; Donahue, Benjamin B.; Chen, Timothy T.

2009-01-01

Future space transportation architectures and designs must be affordable. Consequently, their Life Cycle Cost (LCC) must be controlled. For the LCC to be controlled, it is necessary to identify all the requirements and elements of the architecture at the beginning of the concept phase. Controlling LCC requires the establishment of the major operational cost drivers. Two of these major cost drivers are reliability and maintainability, in other words, the system's availability (responsiveness). Potential reasons that may drive the inherent availability requirement are the need to control the number of unique parts and the spare parts required to support the transportation system's operation. For more typical space transportation systems used to place satellites in space, the productivity of the system will drive the launch cost. This system productivity is the resultant output of the system availability. Availability is equal to the mean uptime divided by the sum of the mean uptime plus the mean downtime. Since many operational factors cannot be projected early in the definition phase, the focus will be on inherent availability which is equal to the mean time between a failure (MTBF) divided by the MTBF plus the mean time to repair (MTTR) the system. The MTBF is a function of reliability or the expected frequency of failures. When the system experiences failures the result is added operational flow time, parts consumption, and increased labor with an impact to responsiveness resulting in increased LCC. The other function of availability is the MTTR, or maintainability. In other words, how accessible is the failed hardware that requires replacement and what operational functions are required before and after change-out to make the system operable. This paper will describe how the MTTR can be equated to additional labor, additional operational flow time, and additional structural access capability, all of which drive up the LCC. A methodology will be presented that

Approach to an Affordable and Sustainable Space Transportation System

Science.gov (United States)

McCleskey, Caey M.; Rhodes, R. E.; Robinson, J. W.; Henderson, E. M.

2012-01-01

This paper describes an approach and a general procedure for creating space transportation architectural concepts that are at once affordable and sustainable. Previous papers by the authors and other members of the Space Propulsion Synergy Team (SPST) focused on a functional system breakdown structure for an architecture and definition of high-payoff design techniques with a technology integration strategy. This paper follows up by using a structured process that derives architectural solutions focused on achieving life cycle affordability and sustainability. Further, the paper includes an example concept that integrates key design techniques discussed in previous papers. !

The role of space charge compensation for ion beam extraction and ion beam transport (invited)

International Nuclear Information System (INIS)

Spädtke, Peter

2014-01-01

Depending on the specific type of ion source, the ion beam is extracted either from an electrode surface or from a plasma. There is always an interface between the (almost) space charge compensated ion source plasma, and the extraction region in which the full space charge is influencing the ion beam itself. After extraction, the ion beam is to be transported towards an accelerating structure in most cases. For lower intensities, this transport can be done without space charge compensation. However, if space charge is not negligible, the positive charge of the ion beam will attract electrons, which will compensate the space charge, at least partially. The final degree of Space Charge Compensation (SCC) will depend on different properties, like the ratio of generation rate of secondary particles and their loss rate, or the fact whether the ion beam is pulsed or continuous. In sections of the beam line, where the ion beam is drifting, a pure electrostatic plasma will develop, whereas in magnetic elements, these space charge compensating electrons become magnetized. The transport section will provide a series of different plasma conditions with different properties. Different measurement tools to investigate the degree of space charge compensation will be described, as well as computational methods for the simulation of ion beams with partial space charge compensation

From microsystems technology to the Saenger II space transportation system

Science.gov (United States)

Vogels, Hanns Arnt

The role of space projects as drivers and catalysts of technology advances is discussed and illustrated from the perspective of the West German aerospace industry, summarizing a talk presented at the 1986 meeting of the German aerospace society DGLR. The history of space-transportation-system (STS) technology since the 1950s is traced, emphasizing the needs for greater payload weights and lower costs, and the design concept of Saenger II, a proposed two-stage ESA STS employing a hypersonic jet transport aircraft as its first stage, is outlined. It is argued that experience gained in developing the rocket-launched Hermes STS will be applicable to the second stage of Saenger II. Recent developments in microsystems (combining microelectronics, micromechanics, and microoptics), advanced materials (fiber-reinforced plastics, metals, and ceramics), and energy technology (hydrogen-based systems and solar cells) are surveyed, and their applicability to STSs is considered.

Transport processes in space plasmas

International Nuclear Information System (INIS)

Birn, J.; Elphic, R.C.; Feldman, W.C.

1997-01-01

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project represents a comprehensive research effort to study plasma and field transport processes relevant for solar-terrestrial interaction, involving the solar wind and imbedded magnetic field and plasma structures, the bow shock of the Earth's magnetosphere and associated waves, the Earth's magnetopause with imbedded flux rope structures and their connection with the Earth, plasma flow in the Earth's magnetotail, and ionospheric beam/wave interactions. The focus of the work was on the interaction between plasma and magnetic and electric fields in the regions where different plasma populations exist adjacent to or superposed on each other. These are the regions of particularly dynamic plasma behavior, important for plasma and energy transport and rapid energy releases. The research addressed questions about how this interaction takes place, what waves, instabilities, and particle/field interactions are involved, how the penetration of plasma and energy through characteristic boundaries takes place, and how the characteristic properties of the plasmas and fields of the different populations influence each other on different spatial and temporal scales. These topics were investigated through combining efforts in the analysis of plasma and field data obtained through space missions with theory and computer simulations of the plasma behavior

Silica sulfuric acid: a versatile and reusable heterogeneous catalyst ...

African Journals Online (AJOL)

... and reusable heterogeneous catalyst for the synthesis of N-acyl carbamates and ... All the reactions were done at room temperature and the N-acyl carbamates ... This method is attractive and is in a close agreement with green chemistry.

Demands for Space Transportation Systems for the next 30 years

Indian Academy of Sciences (India)

First page Back Continue Last page Overview Graphics. Demands for Space Transportation Systems for the next 30 years. Meeting the in-house and commercial launch demand for Communication and Remote Sensing spacecraft. Payload capability enhancement for expendable launch vehicles to meet the national needs.

NASA Earth-to-Orbit Engineering Design Challenges: Thermal Protection Systems

Science.gov (United States)

National Aeronautics and Space Administration (NASA), 2010

2010-01-01

National Aeronautics and Space Administration (NASA) Engineers at Marshall Space Flight Center, Dryden Flight Research Center, and their partners at other NASA centers and in private industry are currently developing X-33, a prototype to test technologies for the next generation of space transportation. This single-stage-to-orbit reusable launch…

FAA's Implementation of the Commercial Space Launch Amendments Act of 2004- The Experimental Permit

Science.gov (United States)

Repcheck, J. Randall

2005-12-01

A number of entrepreneurs are committed to the goal of developing and operating reusable launch vehicles for private human space travel. In order to promote this emerging industry, and to create a clear legal, regulatory, and safety regime, the United States (U.S.) Congress passed the Commercial Space Launch Amendments Act of 2004 (CSLAA). Signed on December 23, 2004 by U.S. President George W. Bush, the CSLAA makes the Federal Aviation Administration (FAA) responsible for regulating human spaceflight. The CSLAA, among other things, establishes an experimental permit regime for developmental reusable suborbital rockets. This paper describes the FAA's approach in developing guidelines for obtaining and maintaining an experimental permit, and describes the core safety elements of those guidelines.

Reusable launch vehicle development research

Science.gov (United States)

1995-01-01

NASA has generated a program approach for a SSTO reusable launch vehicle technology (RLV) development which includes a follow-on to the Ballistic Missile Defense Organization's (BMDO) successful DC-X program, the DC-XA (Advanced). Also, a separate sub-scale flight demonstrator, designated the X-33, will be built and flight tested along with numerous ground based technologies programs. For this to be a successful effort, a balance between technical, schedule, and budgetary risks must be attained. The adoption of BMDO's 'fast track' management practices will be a key element in the eventual success of NASA's effort.

Numerical design of electron guns and space charge limited transport systems

International Nuclear Information System (INIS)

Herrmannsfeldt, W.B.

1980-10-01

This paper describes the capabilities and limitations of computer programs used to design electron guns and similarly space-charge limited transport systems. Examples of computer generated plots from several different types of gun problems are included

Determination of albumin transport rate between plasma and peritoneal space in decompensated cirrhosis

DEFF Research Database (Denmark)

Ring-Larsen, H; Henriksen, Jens Henrik Sahl

1984-01-01

Plasma-to-peritoneal transport rate of albumin (TERperit.space) was determined in eighteen patients with decompensated cirrhosis by sampling ascitic fluid after i.v. injection of 125I-labelled serum albumin. Median TERperit.space was 0.30% of the intravascular albumin mass (IVM) per hour (range 0...

A reusable multi-agent architecture for active intelligent websites

NARCIS (Netherlands)

Jonker, C.M.; Lam, R.A.; Treur, J.

In this paper a reusable multi-agent architecture for intelligent Websites is presented and illustrated for an electronic department store. The architecture has been designed and implemented using the compositional design method for multi-agent systems DESIRE. The agents within this architecture are

Reusable launch vehicles, enabling technology for the development of advanced upper stages and payloads

International Nuclear Information System (INIS)

Metzger, John D.

1998-01-01

In the near future there will be classes of upper stages and payloads that will require initial operation at a high-earth orbit to reduce the probability of an inadvertent reentry that could result in a detrimental impact on humans and the biosphere. A nuclear propulsion system, such as was being developed under the Space Nuclear Thermal Propulsion (SNTP) Program, is an example of such a potential payload. This paper uses the results of a reusable launch vehicle (RLV) study to demonstrate the potential importance of a Reusable Launch Vehicle (RLV) to test and implement an advanced upper stage (AUS) or payload in a safe orbit and in a cost effective and reliable manner. The RLV is a horizontal takeoff and horizontal landing (HTHL), two-stage-to-orbit (TSTO) vehicle. The results of the study shows that an HTHL is cost effective because it implements airplane-like operation, infrastructure, and flight operations. The first stage of the TSTO is powered by Rocket-Based-Combined-Cycle (RBCC) engines, the second stage is powered by a LOX/LH rocket engine. The TSTO is used since it most effectively utilizes the capability of the RBCC engine. The analysis uses the NASA code POST (Program to Optimize Simulated Trajectories) to determine trajectories and weight in high-earth orbit for AUS/advanced payloads. Cost and reliability of an RLV versus current generation expandable launch vehicles are presented

Applying design principles to fusion reactor configurations for propulsion in space

International Nuclear Information System (INIS)

Carpenter, S.A.; Deveny, M.E.; Schulze, N.R.

1993-01-01

The application of fusion power to space propulsion requires rethinking the engineering-design solution to controlled-fusion energy. Whereas the unit cost of electricity (COE) drives the engineering-design solution for utility-based fusion reactor configurations; initial mass to low earth orbit (IMLEO), specific jet power (kW(thrust)/kg(engine)), and reusability drive the engineering-design solution for successful application of fusion power to space propulsion. Three design principles (DP's) were applied to adapt and optimize three candidate-terrestrial-fusion-reactor configurations for propulsion in space. The three design principles are: provide maximum direct access to space for waste radiation, operate components as passive radiators to minimize cooling-system mass, and optimize the plasma fuel, fuel mix, and temperature for best specific jet power. The three candidate terrestrial fusion reactor configurations are: the thermal barrier tandem mirror (TBTM), field reversed mirror (FRM), and levitated dipole field (LDF). The resulting three candidate space fusion propulsion systems have their IMLEO minimized and their specific jet power and reusability maximized. A preliminary rating of these configurations was performed, and it was concluded that the leading engineering-design solution to space fusion propulsion is a modified TBTM that we call the Mirror Fusion Propulsion System (MFPS)

Self-Healing Nanocomposites for Reusable Composite Cryotanks

Science.gov (United States)

Eberly, Daniel; Ou, Runqing; Karcz, Adam; Skandan, Ganesh

2013-01-01

Composite cryotanks, or composite overwrapped pressure vessels (COPVs), offer advantages over currently used aluminum-lithium cryotanks, particularly with respect to weight savings. Future NASA missions are expected to use COPVs in spaceflight propellant tanks to store fuels, oxidizers, and other liquids for launch and space exploration vehicles. However, reliability, reparability, and reusability of the COPVs are still being addressed, especially in cryogenic temperature applications; this has limited the adoption of COPVs in reusable vehicle designs. The major problem with composites is the inherent brittleness of the epoxy matrix, which is prone to microcrack formation, either from exposure to cryogenic conditions or from impact from different sources. If not prevented, the microcracks increase gas permeation and leakage. Accordingly, materials innovations are needed to mitigate microcrack damage, and prevent damage in the first place, in composite cryotanks. The self-healing technology being developed is capable of healing the microcracks through the use of a novel engineered nanocomposite, where a uniquely designed nanoparticle additive is incorporated into the epoxy matrix. In particular, this results in an enhancement in the burst pressure after cryogenic cycling of the nanocomposite COPVs, relative to the control COPVs. Incorporating a novel, self-healing, epoxy-based resin into the manufacture of COPVs allows repeatable self-healing of microcracks to be performed through the simple application of a low-temperature heat source. This permits COPVs to be reparable and reusable with a high degree of reliability, as microcracks will be remediated. The unique phase-separated morphology that was imparted during COPV manufacture allows for multiple self-healing cycles. Unlike single-target approaches where one material property is often improved at the expense of another, robustness has been introduced to a COPV by a combination of a modified resin and

Method for Controlling Space Transportation System Life Cycle Costs

Science.gov (United States)

McCleskey, Carey M.; Bartine, David E.

2006-01-01

A structured, disciplined methodology is required to control major cost-influencing metrics of space transportation systems during design and continuing through the test and operations phases. This paper proposes controlling key space system design metrics that specifically influence life cycle costs. These are inclusive of flight and ground operations, test, and manufacturing and infrastructure. The proposed technique builds on today's configuration and mass properties control techniques and takes on all the characteristics of a classical control system. While the paper does not lay out a complete math model, key elements of the proposed methodology are explored and explained with both historical and contemporary examples. Finally, the paper encourages modular design approaches and technology investments compatible with the proposed method.

Bacterial contamination of re-usable laryngoscope blades during the ...

African Journals Online (AJOL)

We aimed to assess the level of microbial contamination of re-usable laryngoscope blades at a public hospital in South Africa. Setting. The theatre complex of a secondary-level public hospital in Johannesburg. Methods. Blades from two different theatres were sampled twice daily, using a standardised technique, over a ...

The development of a type B(U) transport container design in cast and forged stainless steel for the transport of immobilised intermediate level waste

International Nuclear Information System (INIS)

Sievwright, B.; Dixon, P.; Tso, C.F.

2004-01-01

United Kingdom Nirex Limited (Nirex) is responsible for providing the United Kingdom with safe, environmentally sound and publicly acceptable options for the long-term management of radioactive materials. This includes intermediate level (ILW) and some low level (LLW) wastes. As part of its role Nirex has defined standards and specifications for the conditioning and packaging of these wastes, and carries out assessments of packaging proposals to ensure compatibility with the requirements for future phases of waste management. In order to facilitate this process and to provide a basis for the production of waste package specifications, Nirex has developed the Phased Disposal Concept, and produced a suite of underpinning safety and performance assessments. It has also undertaken work to assess the compatibility of its waste packaging specifications with other waste management options. The Phased Disposal Concept continues to be developed and updated to incorporate issues arising from dialogue with stakeholders, including members of the public; future changes arising from Government policy, legislation and regulations; information from waste producers, and the results from on-going research and development. One of the documents describing the Phased Disposal Concept is the Generic Transport System Design (GTSD). The GTSD outlines the range of waste packages to be transported and disposed of, and describes the design of the transport system needed to transport wastes from their sites of production or storage to a centralised phased disposal facility site. It also describes a range of re-usable transport containers which could be used to transport those waste packages, which require Type B standards for transport, through the public domain. This paper describes the development to date of such a design of reusable transport container, known as the SWTC-285, the Standard Waste Transport Container (SWTC) with 285 mm of shielding

Advanced Space Transportation Concepts and Propulsion Technologies for a New Delivery Paradigm

Science.gov (United States)

Robinson, John W.; McCleskey, Carey M.; Rhodes, Russel E.; Lepsch, Roger A.; Henderson, Edward M.; Joyner, Claude R., III; Levack, Daniel J. H.

2013-01-01

This paper describes Advanced Space Transportation Concepts and Propulsion Technologies for a New Delivery Paradigm. It builds on the work of the previous paper "Approach to an Affordable and Productive Space Transportation System". The scope includes both flight and ground system elements, and focuses on their compatibility and capability to achieve a technical solution that is operationally productive and also affordable. A clear and revolutionary approach, including advanced propulsion systems (advanced LOX rich booster engine concept having independent LOX and fuel cooling systems, thrust augmentation with LOX rich boost and fuel rich operation at altitude), improved vehicle concepts (autogeneous pressurization, turbo alternator for electric power during ascent, hot gases to purge system and keep moisture out), and ground delivery systems, was examined. Previous papers by the authors and other members of the Space Propulsion Synergy Team (SPST) focused on space flight system engineering methods, along with operationally efficient propulsion system concepts and technologies. This paper continues the previous work by exploring the propulsion technology aspects in more depth and how they may enable the vehicle designs from the previous paper. Subsequent papers will explore the vehicle design, the ground support system, and the operations aspects of the new delivery paradigm in greater detail.

Cost comparison of re-usable and single-use fibrescopes in a large English teaching hospital.

Science.gov (United States)

McCahon, R A; Whynes, D K

2015-06-01

A number of studies in the U.S.A. and mainland Europe have described the costs of fibreoptic tracheal intubation. However, no such data from the UK appear available. We performed a cost assessment of fibreoptic intubation, using re-usable (various devices from Olympus, Acutronic and Karl Storz) and single-use (Ambu aScope) fibrescopes, at the Queens Medical Centre, Nottingham, U.K., between 1 January 2009 and 31 March 2014. The total annual cost of fibreoptic intubation with re-usable fibrescopes was £46,385. Based on 141 fibreoptic intubations per year, this equated to £329 per use, an average dominated by repair/maintenance costs (43%) and capital depreciation costs (42%). In comparison, the total annual cost of using single-use fibrescopes for the same work would have been around £200 per use. The analysis enabled us to develop a generic model, wherein we were able to describe the relationship between total cost of use vs number of uses for a fibrescope. An 'isopleth' was identified for this relationship: a line that joined all the points where the cost of re-usable vs single-use fibrescopes was equal. It appears cheaper to use single-use fibrescopes at up to 200 fibreoptic intubations per year (a range commensurate with normal practice) even when the repair rate for re-usable fibrescopes is low. Any centre, knowing its fibrescope use and repair rate, can plot its data similarly to help ascertain which of the re-usable or single-use fibrescope represents better value. © 2015 The Association of Anaesthetists of Great Britain and Ireland.

An Automatic Indicator of the Reusability of Learning Objects Based on Metadata That Satisfies Completeness Criteria

Science.gov (United States)

Sanz-Rodríguez, Javier; Margaritopoulos, Merkourios; Margaritopoulos, Thomas; Dodero, Juan Manuel; Sánchez-Alonso, Salvador; Manitsaris, Athanasios

The search for learning objects in open repositories is currently a tedious task, owing to the vast amount of resources available and the fact that most of them do not have associated ratings to help users make a choice. In order to tackle this problem, we propose a reusability indicator, which can be calculated automatically using the metadata that describes the objects, allowing us to select those materials most likely to be reused. In order for this reusability indicator to be applied, metadata records must reach a certain amount of completeness, guaranteeing that the material is adequately described. This reusability indicator is tested in two studies on the Merlot and eLera repositories, and results obtained offer evidence to support their effectiveness.

Environmental considerations in the selection of isolation gowns: A life cycle assessment of reusable and disposable alternatives.

Science.gov (United States)

Vozzola, Eric; Overcash, Michael; Griffing, Evan

2018-04-11

Isolation gowns serve a critical role in infection control by protecting healthcare workers, visitors, and patients from the transfer of microorganisms and body fluids. The decision of whether to use a reusable or disposable garment system is a selection process based on factors including sustainability, barrier effectiveness, cost, and comfort. Environmental sustainability is increasingly being used in the decision-making process. Life cycle assessment is the most comprehensive and widely used tool used to evaluate environmental performance. The environmental impacts of market-representative reusable and disposable isolation gown systems were compared using standard life cycle assessment procedures. The basis of comparison was 1,000 isolation gown uses in a healthcare setting. The scope included the manufacture, use, and end-of-life stages of the gown systems. At the healthcare facility, compared to the disposable gown system, the reusable gown system showed a 28% reduction in energy consumption, a 30% reduction in greenhouse gas emissions, a 41% reduction in blue water consumption, and a 93% reduction in solid waste generation. Selecting reusable garment systems may result in significant environmental benefits compared to selecting disposable garment systems. By selecting reusable isolation gowns, healthcare facilities can add these quantitative benefits directly to their sustainability scorecards. Copyright © 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Towards a reusable architecture for message exchange in pervasive healthcare

NARCIS (Netherlands)

Cardoso de Moraes, J.L.; Lopes de Souza, Wanderley; Ferreira Pires, Luis; do Prado, Antonio Francisco; Hammoudi, S.; Maciaszek, L.A.; Cordeiro, J.; Dietz, J.L.G.

The main objective of this paper is to present a reusable architecture for message exchange in pervasive healthcare environments meant to be generally applicable to different applications in the healthcare domain. This architecture has been designed by integrating different concepts and technologies

Developing a Toolset Supporting the Construction of Reusable Components for Embedded Control Systems

DEFF Research Database (Denmark)

Guan, Wei; Sierszecki, Krzysztof; Angelov, Christo K.

2010-01-01

Reusing software components for embedded control applications enhances product quality and reduces time to market when appropriate (formal) methodologies and supporting toolsets are available. That is why industrial companies are interested in developing trusted, in-house reusable components for ...... on open-source technology, in accordance with industrial requirements, as well as the approach used to engineer a toolset supporting component development for embedded control applications.......Reusing software components for embedded control applications enhances product quality and reduces time to market when appropriate (formal) methodologies and supporting toolsets are available. That is why industrial companies are interested in developing trusted, in-house reusable components...

A Reusable Framework for Regional Climate Model Evaluation

Science.gov (United States)

Hart, A. F.; Goodale, C. E.; Mattmann, C. A.; Lean, P.; Kim, J.; Zimdars, P.; Waliser, D. E.; Crichton, D. J.

2011-12-01

Climate observations are currently obtained through a diverse network of sensors and platforms that include space-based observatories, airborne and seaborne platforms, and distributed, networked, ground-based instruments. These global observational measurements are critical inputs to the efforts of the climate modeling community and can provide a corpus of data for use in analysis and validation of climate models. The Regional Climate Model Evaluation System (RCMES) is an effort currently being undertaken to address the challenges of integrating this vast array of observational climate data into a coherent resource suitable for performing model analysis at the regional level. Developed through a collaboration between the NASA Jet Propulsion Laboratory (JPL) and the UCLA Joint Institute for Regional Earth System Science and Engineering (JIFRESSE), the RCMES uses existing open source technologies (MySQL, Apache Hadoop, and Apache OODT), to construct a scalable, parametric, geospatial data store that incorporates decades of observational data from a variety of NASA Earth science missions, as well as other sources into a consistently annotated, highly available scientific resource. By eliminating arbitrary partitions in the data (individual file boundaries, differing file formats, etc), and instead treating each individual observational measurement as a unique, geospatially referenced data point, the RCMES is capable of transforming large, heterogeneous collections of disparate observational data into a unified resource suitable for comparison to climate model output. This facility is further enhanced by the availability of a model evaluation toolkit which consists of a set of Python libraries, a RESTful web service layer, and a browser-based graphical user interface that allows for orchestration of model-to-data comparisons by composing them visually through web forms. This combination of tools and interfaces dramatically simplifies the process of interacting with and

Humidifiers for oxygen therapy: what risk for reusable and disposable devices?

Science.gov (United States)

La Fauci, V; Costa, G B; Facciolà, A; Conti, A; Riso, R; Squeri, R

2017-06-01

Nosocomial pneumonia accounts for the vast majority of healthcare-associated infections (HAI). Although numerous medical devices have been discussed as potential vehicles for microorganisms, very little is known about the role played by oxygen humidifiers as potential sources of nosocomial pathogens. The purpose of this research was to evaluate the safety of the reuse of humidifiers by analysing the rate of microbial contamination in reusable and disposable oxygen humidifiers used during therapy, and then discuss their potential role in the transmission of respiratory pathogens. Water samples from reusable and disposable oxygen humidifiers were collected from different wards of the University Hospital of Messina, Italy, where nosocomial pneumonia has a higher incidence rate due to the "critical" clinical conditions of inpatients. In particular, we monitored the Internal Medicine and Pulmonology wards for the medical area; the General Surgery and Thoracic and Cardiovascular Surgery wards for the surgical area and the Intensive Care Unit and Neonatal Intensive Care Unit for the emergency area. The samples were always collected after a period of 5 days from initial use for both types of humidifiers. Samples were processed using standard bacteriological techniques and microbial colonies were identified using manual and automated methods. High rates of microbial contamination were observed in samples from reusable oxygen humidifiers employed in medical (83%), surgical (77%) and emergency (50%) areas. The most relevant pathogens were Pseudomonas aeruginosa, amongst the Gram-negative bacteria, and Staphylococcus aureus, amongst the Gram-positive bacteria. Other pathogens were detected in lower percentage. The disposable oxygen humidifier samples showed no contamination. This research presents evidence of the high rate and type of microbial contamination of reusable humidifiers employed for oxygen therapy. These devices may thus be involved in the transmission of potential

A solution of the monoenergetic neutral particle transport equation for adjacent half-spaces with anisotropic scattering

Energy Technology Data Exchange (ETDEWEB)

Ganapol, B.D., E-mail: ganapol@cowboy.ame.arizona.edu [Department of Aerospace and Mechanical Engineering, University of Arizona, Tucson, AZ (United States); Mostacci, D.; Previti, A. [Montecuccolino Laboratory, University of Bologna, Via dei Colli, 16, I-40136 Bologna (Italy)

2016-07-01

We present highly accurate solutions to the neutral particle transport equation in a half-space. While our initial motivation was in response to a recently published solution based on Chandrasekhar's H-function, the presentation to follow has taken on a more comprehensive tone. The solution by H-functions certainly did achieved high accuracy but was limited to isotropic scattering and emission from spatially uniform and linear sources. Moreover, the overly complicated nature of the H-function approach strongly suggests that its extension to anisotropic scattering and general sources is not at all practical. For this reason, an all encompassing theory for the determination of highly precise benchmarks, including anisotropic scattering for a variety of spatial source distributions, is presented for particle transport in a half-space. We illustrate the approach via a collection of cases including tables of 7-place flux benchmarks to guide transport methods developers. The solution presented can be applied to a considerable number of one and two half-space transport problems with variable sources and represents a state-of-the-art benchmark solution.

The SPACE 1.0 model: a Landlab component for 2-D calculation of sediment transport, bedrock erosion, and landscape evolution

Science.gov (United States)

Shobe, Charles M.; Tucker, Gregory E.; Barnhart, Katherine R.

2017-12-01

Models of landscape evolution by river erosion are often either transport-limited (sediment is always available but may or may not be transportable) or detachment-limited (sediment must be detached from the bed but is then always transportable). While several models incorporate elements of, or transition between, transport-limited and detachment-limited behavior, most require that either sediment or bedrock, but not both, are eroded at any given time. Modeling landscape evolution over large spatial and temporal scales requires a model that can (1) transition freely between transport-limited and detachment-limited behavior, (2) simultaneously treat sediment transport and bedrock erosion, and (3) run in 2-D over large grids and be coupled with other surface process models. We present SPACE (stream power with alluvium conservation and entrainment) 1.0, a new model for simultaneous evolution of an alluvium layer and a bedrock bed based on conservation of sediment mass both on the bed and in the water column. The model treats sediment transport and bedrock erosion simultaneously, embracing the reality that many rivers (even those commonly defined as bedrock rivers) flow over a partially alluviated bed. SPACE improves on previous models of bedrock-alluvial rivers by explicitly calculating sediment erosion and deposition rather than relying on a flux-divergence (Exner) approach. The SPACE model is a component of the Landlab modeling toolkit, a Python-language library used to create models of Earth surface processes. Landlab allows efficient coupling between the SPACE model and components simulating basin hydrology, hillslope evolution, weathering, lithospheric flexure, and other surface processes. Here, we first derive the governing equations of the SPACE model from existing sediment transport and bedrock erosion formulations and explore the behavior of local analytical solutions for sediment flux and alluvium thickness. We derive steady-state analytical solutions for

The Lunar Space Tug: A sustainable bridge between low Earth orbits and the Cislunar Habitat

Science.gov (United States)

Mammarella, M.; Paissoni, C. A.; Viola, N.; Denaro, A.; Gargioli, E.; Massobrio, F.

2017-09-01

The International Space Station is the first space human outpost and over the last 15 years, it has represented a peculiar environment where science, technology and human innovation converge together in a unique microgravity and space research laboratory. With the International Space Station entering the second part of its life and its operations running steadily at nominal pace, the global space community is starting planning how the human exploration could move further, beyond Low-Earth-Orbit. According to the Global Exploration Roadmap, the Moon represents the next feasible path-way for advances in human exploration towards the nal goal, Mars. Based on the experience of the ISS, one of the most widespread ideas is to develop a Cislunar Station in preparation of long duration missions in a deep space environment. Cislunar space is de ned as the area of deep space under the influence of Earth-Moon system, including a set of special orbits, e.g. Earth-Moon Libration points and Lunar Retrograde Orbit. This habitat represents a suitable environment for demonstrating and testing technologies and capabilities in deep space. In order to achieve this goal, there are several crucial systems and technologies, in particular related to transportation and launch systems. The Orion Multi-Purpose Crew Vehicle is a reusable transportation capsule designed to provide crew transportation in deep space missions, whereas NASA is developing the Space Launch System, the most powerful rocket ever built, which could provide the necessary heavy-lift launch capability to support the same kind of missions. These innovations would allow quite-fast transfers from Earth to the Cislunar Station and vice versa, both for manned and unmanned missions. However, taking into account the whole Concept of Operations for both the growth and sustainability of the Cislunar Space Station, the Lunar Space Tug can be considered as an additional, new and fundamental element for the mission architecture. The

Schoolgirls' experience and appraisal of menstrual absorbents in rural Uganda: a cross-sectional evaluation of reusable sanitary pads.

Science.gov (United States)

Hennegan, Julie; Dolan, Catherine; Wu, Maryalice; Scott, Linda; Montgomery, Paul

2016-12-07

Governments, multinational organisations, and charities have commenced the distribution of sanitary products to address current deficits in girls' menstrual management. The few effectiveness studies conducted have focused on health and education outcomes but have failed to provide quantitative assessment of girls' preferences, experiences of absorbents, and comfort. Objectives of the study were, first, to quantitatively describe girls' experiences with, and ratings of reliability and acceptability of different menstrual absorbents. Second, to compare ratings of freely-provided reusable pads (AFRIpads) to other existing methods of menstrual management. Finally, to assess differences in self-reported freedom of activity during menses according to menstrual absorbent. Cross-sectional, secondary analysis of data from the final survey of a controlled trial of reusable sanitary padand puberty education provision was undertaken. Participants were 205 menstruating schoolgirls from eight schools in rural Uganda. 72 girls who reported using the intervention-provided reusable pads were compared to those using existing improvised methods (predominately new or old cloth). Schoolgirls using reusable pads provided significantly higher ratings of perceived absorbent reliability across activities, less difficulties changing absorbents, and less disgust with cleaning absorbents. There were no significant differences in reports of outside garment soiling (OR 1.00 95%CI 0.51-1.99), or odour (0.84 95%CI 0.40-1.74) during the last menstrual period. When girls were asked if menstruation caused them to miss daily activities there were no differences between those using reusable pads and those using other existing methods. However, when asked about activities avoided during menstruation, those using reusable pads participated less in physical sports, working in the field, fetching water, and cooking. Reusable pads were rated favourably. This translated into some benefits for self

An Affordability Comparison Tool (ACT) for Space Transportation

Science.gov (United States)

McCleskey, C. M.; Bollo, T. R.; Garcia, J. L.

2012-01-01

NASA bas recently emphasized the importance of affordability for Commercial Crew Development Program (CCDP), Space Launch Systems (SLS) and Multi-Purpose Crew Vehicle (MPCV). System architects and designers are challenged to come up with architectures and designs that do not bust the budget. This paper describes the Affordability Comparison Tool (ACT) analyzes different systems or architecture configurations for affordability that allows for a comparison of: total life cycle cost; annual recurring costs, affordability figures-of-merit, such as cost per pound, cost per seat, and cost per flight, as well as productivity measures, such as payload throughput. Although ACT is not a deterministic model, the paper develops algorithms and parametric factors that use characteristics of the architectures or systems being compared to produce important system outcomes (figures-of-merit). Example applications of outcome figures-of-merit are also documented to provide the designer with information on the relative affordability and productivity of different space transportation applications.

SpaceX Dragon Air Circulation System

Science.gov (United States)

Hernandez, Brenda; Piatrovich, Siarhei; Prina, Mauro

2011-01-01

The Dragon capsule is a reusable vehicle being developed by Space Exploration Technologies (SpaceX) that will provide commercial cargo transportation to the International Space Station (ISS). Dragon is designed to be a habitable module while it is berthed to ISS. As such, the Dragon Environmental Control System (ECS) consists of pressure control and pressure equalization, air sampling, fire detection, illumination, and an air circulation system. The air circulation system prevents pockets of stagnant air in Dragon that can be hazardous to the ISS crew. In addition, through the inter-module duct, the air circulation system provides fresh air from ISS into Dragon. To utilize the maximum volume of Dragon for cargo packaging, the Dragon ECS air circulation system is designed around cargo rack optimization. At the same time, the air circulation system is designed to meet the National Aeronautics Space Administration (NASA) inter-module and intra-module ventilation requirements and acoustic requirements. A flight like configuration of the Dragon capsule including the air circulation system was recently assembled for testing to assess the design for inter-module and intra-module ventilation and acoustics. The testing included the Dragon capsule, and flight configuration in the pressure section with cargo racks, lockers, all of the air circulation components, and acoustic treatment. The air circulation test was also used to verify the Computational Fluid Dynamics (CFD) model of the Dragon capsule. The CFD model included the same Dragon internal geometry that was assembled for the test. This paper will describe the Dragon air circulation system design which has been verified by testing the system and with CFD analysis.

Triggered lightning risk assessment for reusable launch vehicles at four regional spaceports

Science.gov (United States)

2010-04-30

The Aerospace Corporation was tasked by the Volpe National Transportation Systems Center to provide technical support to the Federal Aviation Administration, Office of Commercial Space Transportation, in assessing the risks involved with triggered li...

Development and flight test of metal-lined CFRP cryogenic tank for reusable rocket

Science.gov (United States)

Higuchi, Ken; Takeuchi, Shinsuke; Sato, Eiichi; Naruo, Yoshihiro; Inatani, Yoshifumi; Namiki, Fumiharu; Tanaka, Kohtaro; Watabe, Yoko

2005-07-01

A cryogenic tank made of carbon fiber reinforced plastic (CFRP) shell with aluminum thin liner has been designed as a liquid hydrogen (LH2) tank for an ISAS reusable launch vehicle, and the function of it has been proven by repeated flights onboard the test vehicle called reusable vehicle testing (RVT) in October 2003. The liquid hydrogen tank has to be a pressure vessel, because the fuel of the engine of the test vehicle is supplied by fuel pressure. The pressure vessel of a combination of the outer shell of CFRP for strength element at a cryogenic temperature and the inner liner of aluminum for gas barrier has shown excellent weight merit for this purpose. Interfaces such as tank outline shape, bulk capacity, maximum expected operating pressure (MEOP), thermal insulation, pipe arrangement, and measurement of data are also designed to be ready onboard. This research has many aims, not only development of reusable cryogenic composite tank but also the demonstration of repeated operation including thermal cycle and stress cycle, familiarization with test techniques of operation of cryogenic composite tanks, and the accumulation of data for future design of tanks, vehicle structures, safety evaluation, and total operation systems.

A reusable OSL-film for 2D radiotherapy dosimetry

Science.gov (United States)

Wouter, Crijns; Dirk, Vandenbroucke; Paul, Leblans; Tom, Depuydt

2017-11-01

Optical stimulated luminescence (OSL) combines reusability, sub-mm resolution, and a linear dose response in a single radiation detection technology. Such a combination is currently lacking in radiotherapy dosimetry. But OSL-films have a strong energy dependent response to keV photons due to a relative high effective atomic number (Z eff). The current work studied the applicability of a 2D OSL-film with a reduced Z eff as (IMRT/VMAT) dosimeter. Based on their commercial OSL-film experience, Agfa Healthcare N.V. produced a new experimental OSL-film for RT dosimetry. This film had a lower effective atomic number compared to the films used in radiology. Typical 2D dosimeter requirements such as uniformity, dose response, signal stability with time, and angular dependence were evaluated. Additionally, the impact of a possible residual energy dependence was assessed for the infield as well as the out-of-field region of both static beams and standard intensity modulated patterns (chair and pyramid). The OSL-film’s reusable nature allowed for a film specific absolute and linear calibration including a flood-field uniformity correction. The OSL-film was scanned with a CR-15X engine based reader using a strict timing (i.e. 4 min after ‘beam on’ or as soon as possible) to account for spontaneous recombination. The OSL-film had good basic response properties: non-uniformities  ⩽2.6%, a linear dose response (0-32 Gy), a linear signal decay (0.5% min-1) over the 20 min measured, and limited angular dependence  ⩽2.6%. Due to variations of the energy spectrum, larger dose differences were noted outside the central region of the homogenous phantom and outside both static and IMRT fields. However, the OSL-film’s measured dose differences of the IMRT patterns were lower than those of Gafchromic EBT measurements ([-1.6%, 2.1%] versus [-2.9%, 3.6%]). The current OSL-film could be used as a reusable high resolution dosimeter with read-out immediately after

Integration of reusable systems

CERN Document Server

Rubin, Stuart

2014-01-01

Software reuse and integration has been described as the process of creating software systems from existing software rather than building software systems from scratch. Whereas reuse solely deals with the artifacts creation, integration focuses on how reusable artifacts interact with the already existing parts of the specified transformation. Currently, most reuse research focuses on creating and integrating adaptable components at development or at compile time. However, with the emergence of ubiquitous computing, reuse technologies that can support adaptation and reconfiguration of architectures and components at runtime are in demand. This edited book includes 15 high quality research papers written by experts in information reuse and integration to cover the most recent advances in the field. These papers are extended versions of the best papers which were presented at IEEE International Conference on Information Reuse and Integration and IEEE International Workshop on Formal Methods Integration, which wa...

Russian aluminum-lithium alloys for advanced reusable spacecraft

International Nuclear Information System (INIS)

Charette, Ray O.; Leonard, Bruce G.; Bozich, William F.; Deamer, David A.

1998-01-01

Cryotanks that are cost-affordable, robust, fuel-compatible, and lighter weight than current aluminum design are needed to support next-generation launch system performance and operability goals. The Boeing (McDonnell Douglas Aerospace-MDA) and NASA's Delta Clipper-Experimental Program (DC-XA) flight demonstrator test bed vehicle provided the opportunity for technology transfer of Russia's extensive experience base with weight-efficient, highly weldable aluminum-lithium (Al-Li) alloys for cryogenic tank usage. As part of NASA's overall reusable launch vehicle (RLV) program to help provide technology and operations data for use in advanced RLVs, MDA contracted with the Russian Academy of Sciences (RAS/IMASH) for design, test, and delivery of 1460 Al-Li alloy liquid oxygen (LO 2 ) cryotanks: one for development, one for ground tests, and one for DC-XA flight tests. This paper describes the development of Al-Li 1460 alloy for reusable LO 2 tanks, including alloy composition tailoring, mechanical properties database, forming, welding, chemical milling, dissimilar metal joining, corrosion protection, completed tanks proof, and qualification testing. Mechanical properties of the parent and welded materials exceeded expectations, particularly the fracture toughness, which promise excellent reuse potential. The LO 2 cryotank was successfully demonstrated in DC-XA flight tests

Experiences with Reusable E-Learning Objects: From Theory to Practice.

Science.gov (United States)

Muzio, Jeanette A.; Heins, Tanya; Mundell, Roger

2002-01-01

Explains reusable electronic learning objects (ELOs) that are stored in a database and discusses the practical application of creating and reusing ELOs at Royal Roads University (Canada). Highlights include ELOs and the instructional design of online courses; and examples of using templates to develop interactive ELOs. (Author/LRW)

EBQ code: Transport of space-charge beams in axially symmetric devices

Science.gov (United States)

Paul, A. C.

1982-11-01

Such general-purpose space charge codes as EGUN, BATES, WODF, and TRANSPORT do not gracefully accommodate the simulation of relativistic space-charged beams propagating a long distance in axially symmetric devices where a high degree of cancellation has occurred between the self-magnetic and self-electric forces of the beam. The EBQ code was written specifically to follow high current beam particles where space charge is important in long distance flight in axially symmetric machines possessing external electric and magnetic field. EBQ simultaneously tracks all trajectories so as to allow procedures for charge deposition based on inter-ray separations. The orbits are treated in Cartesian geometry (position and momentum) with z as the independent variable. Poisson's equation is solved in cylindrical geometry on an orthogonal rectangular mesh. EBQ can also handle problems involving multiple ion species where the space charge from each must be included. Such problems arise in the design of ion sources where different charge and mass states are present.

EBQ code: transport of space-charge beams in axially symmetric devices

International Nuclear Information System (INIS)

Paul, A.C.

1982-11-01

Such general-purpose space charge codes as EGUN, BATES, WOLF, and TRANSPORT do not gracefully accommodate the simulation of relativistic space-charged beams propagating a long distance in axially symmetric devices where a high degree of cancellation has occurred between the self-magnetic and self-electric forces of the beam. The EBQ code was written specifically to follow high current beam particles where space charge is important in long distance flight in axially symmetric machines possessing external electric and magnetic field. EBQ simultaneously tracks all trajectories so as to allow procedures for charge deposition based on inter-ray separations. The orbits are treated in Cartesian geometry (position and momentum) with z as the independent variable. Poisson's equation is solved in cylindrical geometry on an orthogonal rectangular mesh. EBQ can also handle problems involving multiple ion species where the space charge from each must be included. Such problems arise in the design of ion sources where different charge and mass states are present

Embracing the Importance of FAIR Research Products - Findable, Accessible, Interoperable, and Reusable

Science.gov (United States)

Stall, S.

2017-12-01

Integrity and transparency within research is solidified by a complete set of research products that are findable, accessible, interoperable, and reusable. In other words, they follow the FAIR Guidelines developed by FORCE11.org. Your datasets, images, video, software, scripts, models, physical samples, and other tools and technology are an integral part of the narrative you tell about your research. These research products increasingly are being captured through workflow tools and preserved and connected through persistent identifiers across multiple repositories that keep them safe. They help secure, with your publications, the supporting evidence and integrity of the scientific record. This is the direction that Earth and space science as well as other disciplines is moving. Within our community, some science domains are further along, and others are taking more measured steps. AGU as a publisher is working to support the full scientific record with peer reviewed publications. Working with our community and all the Earth and space science journals, AGU is developing new policies to encourage researchers to plan for proper data preservation and provide data citations along with their research submission and to encourage adoption of best practices throughout the research workflow and data life cycle. Providing incentives, community standards, and easy-to-use tools are some important factors for helping researchers embrace the FAIR Guidelines and support transparency and integrity.

STARS - Supportability Trend Analysis and Reporting System for the National Space Transportation System

Science.gov (United States)

Graham, Leroy J.; Doempke, Gerald T.

1990-01-01

The concept, implementation, and long-range goals of a Supportability Trend Analysis and Reporting System (STARS) for the National Space Transportation System (NSTS) are discussed. The requirement was established as a direct result of the recommendations of the Rogers Commission investigation of the circumstances of the Space Shuttle Challenger accident. STARS outlines the requirements for the supportability-trend data collection, analysis, and reporting requirements that each of the project offices supporting the Space Shuttle are required to provide to the NSTS program office. STARS data give the historic and predictive logistics information necessary for all levels of NSTS management to make safe and cost-effective decisions concerning the smooth flow of Space Shuttle turnaround.

On the Implementation of a European Space Traffic Management System - I. A White Paper

OpenAIRE

Tüllmann, Ralph; Arbinger, Christian; Baskcomb, Stuart; Berdermann, Jens; Fiedler, Hauke; Klock, Erich; Schildknecht, Thomas

2017-01-01

There are high expectations for a global commercial space travel market which is expected to turn into a multi-billion Euro business in the next two decades. Several key players in the space business, companies like Virgin Galactic, SpaceX, Blue Origin or SNC are preparing to serve this market by developing their own ballistic reusable space vehicles to carry humans and cargo payloads into suborbital and Low Earth Orbit (LEO) space. Europe’s single stage to orbit concepts, e.g., REL’s Skylon ...

Enhanced Flexibility and Reusability through State Machine-Based Architectures for Multisensor Intelligent Robotics

Directory of Open Access Journals (Sweden)

Héctor Herrero

2017-05-01

Full Text Available This paper presents a state machine-based architecture, which enhances the flexibility and reusability of industrial robots, more concretely dual-arm multisensor robots. The proposed architecture, in addition to allowing absolute control of the execution, eases the programming of new applications by increasing the reusability of the developed modules. Through an easy-to-use graphical user interface, operators are able to create, modify, reuse and maintain industrial processes, increasing the flexibility of the cell. Moreover, the proposed approach is applied in a real use case in order to demonstrate its capabilities and feasibility in industrial environments. A comparative analysis is presented for evaluating the presented approach versus traditional robot programming techniques.

Reusability Performance of Zinc Oxide Nanoparticles for Photocatalytic Degradation of POME

Science.gov (United States)

Zarifah Zainuri, Nur; Hanis Hayati Hairom, Nur; Abu Bakar Sidik, Dilaelyana; Misdan, Nurasyikin; Yusof, Norhaniza; Wahab Mohammad, Abdul

2018-03-01

Performance and reusability of different zinc oxide nanoparticles (ZnO-PVP and ZnO-PEG) for photocatalytic degradation of palm-mill oil effluent (POME) has been studied. The nanoparticles properties were characterised with fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The TEM results show that ZnO-PEG nanoparticles exhibit the smaller size than ZnO-PVP with less agglomeration. It was found that ZnO-PEG shows better effectiveness than ZnO-PVP in reducing turbidity, colour and increasing the dissolved oxygen (DO). By using two types of reusability methods: (a) oven drying (b) hot water rinsing, the oven drying method portrayed the most efficient route for POME treatment. This research would be a solution to the palm oil industry for photocatalyst recovering as well as reduction of the chemical usage in order to meet the development of advanced and greener technologies.

Space evolution model and empirical analysis of an urban public transport network

Science.gov (United States)

Sui, Yi; Shao, Feng-jing; Sun, Ren-cheng; Li, Shu-jing

2012-07-01

This study explores the space evolution of an urban public transport network, using empirical evidence and a simulation model validated on that data. Public transport patterns primarily depend on traffic spatial-distribution, demands of passengers and expected utility of investors. Evolution is an iterative process of satisfying the needs of passengers and investors based on a given traffic spatial-distribution. The temporal change of urban public transport network is evaluated both using topological measures and spatial ones. The simulation model is validated using empirical data from nine big cities in China. Statistical analyses on topological and spatial attributes suggest that an evolution network with traffic demands characterized by power-law numerical values which distribute in a mode of concentric circles tallies well with these nine cities.

Orion: Design of a system for assured low-cost human access to space

Science.gov (United States)

Elvander, Josh; Heifetz, Andy; Hunt, Teresa; Zhu, Martin

1994-01-01

In recent years, Congress and the American people have begun to seriously question the role and importance of future manned spaceflight. This is mainly due to two factors: a decline in technical competition caused by the collapse of communism, and the high costs associated with the Space Shuttle transportation system. With these factors in mind, the ORION system was designed to enable manned spaceflight at a low cost, while maintaining the ability to carry out diverse missions, each with a high degree of flexibility. It is capable of performing satellite servicing missions, supporting a space station via crew rotation and resupply, and delivering satellites into geosynchronous orbit. The components of the system are a primary launch module, an upper stage, and a manned spacecraft capable of dynamic reentry. For satellite servicing and space station resupply missions, the ORION system utilizes three primary modules, an upper stage, and the spacecraft, which is delivered to low earth orbit and used to rendezvous, transfer materials, and make repairs. For launching a geosynchronous satellite, one primary module and an upper stage are used to deliver the satellite, along with an apogee kick motor, into orbit. The system is designed with reusability and modularity in mind in an attempt to lower cost.

High Efficiency, Transparent, Reusable, and Active PM2.5 Filters by Hierarchical Ag Nanowire Percolation Network.

Science.gov (United States)

Jeong, Seongmin; Cho, Hyunmin; Han, Seonggeun; Won, Phillip; Lee, Habeom; Hong, Sukjoon; Yeo, Junyeob; Kwon, Jinhyeong; Ko, Seung Hwan

2017-07-12

Air quality has become a major public health issue in Asia including China, Korea, and India. Particulate matters are the major concern in air quality. We present the first environmental application demonstration of Ag nanowire percolation network for a novel, electrical type transparent, reusable, and active PM2.5 air filter although the Ag nanowire percolation network has been studied as a very promising transparent conductor in optoelectronics. Compared with previous particulate matter air filter study using relatively weaker short-range intermolecular force in polar polymeric nanofiber, Ag nanowire percolation network filters use stronger long-range electrostatic force to capture PM2.5, and they are highly efficient (>99.99%), transparent, working on an active mode, low power consumption, antibacterial, and reusable after simple washing. The proposed new particulate matter filter can be applied for a highly efficient, reusable, active and energy efficient filter for wearable electronics application.

Integrated Systems Health Management for Space Exploration

Science.gov (United States)

Uckun, Serdar

2005-01-01

Integrated Systems Health Management (ISHM) is a system engineering discipline that addresses the design, development, operation, and lifecycle management of components, subsystems, vehicles, and other operational systems with the purpose of maintaining nominal system behavior and function and assuring mission safety and effectiveness under off-nominal conditions. NASA missions are often conducted in extreme, unfamiliar environments of space, using unique experimental spacecraft. In these environments, off-nominal conditions can develop with the potential to rapidly escalate into mission- or life-threatening situations. Further, the high visibility of NASA missions means they are always characterized by extraordinary attention to safety. ISHM is a critical element of risk mitigation, mission safety, and mission assurance for exploration. ISHM enables: In-space maintenance and repair; a) Autonomous (and automated) launch abort and crew escape capability; b) Efficient testing and checkout of ground and flight systems; c) Monitoring and trending of ground and flight system operations and performance; d) Enhanced situational awareness and control for ground personnel and crew; e) Vehicle autonomy (self-sufficiency) in responding to off-nominal conditions during long-duration and distant exploration missions; f) In-space maintenance and repair; and g) Efficient ground processing of reusable systems. ISHM concepts and technologies may be applied to any complex engineered system such as transportation systems, orbital or planetary habitats, observatories, command and control systems, life support systems, safety-critical software, and even the health of flight crews. As an overarching design and operational principle implemented at the system-of-systems level, ISHM holds substantial promise in terms of affordability, safety, reliability, and effectiveness of space exploration missions.

Reusable Electronics and Adaptable Communication as Implemented in the Odin Modular Robot

DEFF Research Database (Denmark)

Garcia, Ricardo Franco Mendoza; Lyder, Andreas; Christensen, David Johan

2009-01-01

This paper describes the electronics and communication system of Odin, a novel heterogeneous modular robot made of links and joints. The electronics is divided into two printed circuit boards: a General board with reusable components and a Specific board with non-reusable components. While...... electrical signals. The implementations of actuator and power links show that splitting the electronics into General and Specific boards allows rapid development of different types of modules, and an analysis of performance indicates that the communication system is simple, fast and flexible....... As the electronic design reuses approx. 50% of components between two different types of modules, we find it convenient for heterogeneous modular robots where production costs demand a small set of parts. In addition, as the features of the communication system are desirable in modular robots, we think...

Space charge compensation in the Linac4 low energy beam transport line with negative hydrogen ions

Energy Technology Data Exchange (ETDEWEB)

Valerio-Lizarraga, Cristhian A., E-mail: cristhian.alfonso.valerio.lizarraga@cern.ch [CERN, Geneva (Switzerland); Departamento de Investigación en Física, Universidad de Sonora, Hermosillo (Mexico); Lallement, Jean-Baptiste; Lettry, Jacques; Scrivens, Richard [CERN, Geneva (Switzerland); Leon-Monzon, Ildefonso [Facultad de Ciencias Fisico-Matematicas, Universidad Autónoma de Sinaloa, Culiacan (Mexico); Midttun, Øystein [CERN, Geneva (Switzerland); University of Oslo, Oslo (Norway)

2014-02-15

The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Transport using the package IBSimu [T. Kalvas et al., Rev. Sci. Instrum. 81, 02B703 (2010)], which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H{sup −} beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree.

Facility arrangements and the environmental performance of disposable and reusable cups

NARCIS (Netherlands)

Potting, José; Harst-Wintraecken, van der Eugenie

2015-01-01

Purpose: This paper integrates two complementary life cycle assessment (LCA) studies with the aim to advice facility managers on the sustainable use of cups, either disposable or reusable. Study 1 compares three disposable cups, i.e., made from fossil-based polystyrene (PS), biobased and

Commercial suborbital reusable launch vehicles: ushering in a new era for turbopause exploration (Invited)

Science.gov (United States)

Smith, H. T.

2013-12-01

Multiple companies are in the process of developing commercial suborbital reusable launch vehicles (sRLV's). While these companies originally targeted space tourism as the primary customer base, it is rapidly becoming apparent that this dramatic increase in low cost access to space could provide revolutionary opportunities for scientific research, engineering/instrument development and STEM education. These burgeoning capabilities will offer unprecedented opportunities regarding access to space with frequent low-cost access to the region of space from the ground to the boundary of near-Earth space at ~100 km. In situ research of this region is difficult because it is too high for aircraft and balloons and yet too low for orbital satellites and spacecraft. However, this region is very significant because it represents the tenuous boundary of Earth's Atmosphere and Space. It contains a critical portion of the atmosphere where the regime transitions from collisional to non-collisional physics and includes complex charged and neutral particle interactions. These new launch vehicles are currently designed for manned and unmanned flights that reach altitudes up to 110 km for 5K-500K per flight with payload capacity exceeding 600 kg. Considering the much higher cost per flight for a sounding rocket with similar capabilities, high flight cadence, and guaranteed return of payload, commercial spacecraft has the potential to revolutionize access to near space. This unprecedented access to space allows participation at all levels of research, engineering, education and the public at large. For example, one can envision a model where students can conduct complete end to end projects where they design, build, fly and analyze data from individual research projects for thousands of dollars instead of hundreds of thousands. Our community is only beginning to grasp the opportunities and impactions of these new capabilities but with operational flights anticipated in 2014, it is

Sound absorption of low-temperature reusable surface insulation candidate materials

Science.gov (United States)

Johnston, J. D.

1974-01-01

Sound absorption data from tests of four candidate low-temperature reusable surface insulation materials are presented. Limitations on the use of the data are discussed, conclusions concerning the effective absorption of the materials are drawn, and the relative significance to Vibration and Acoustic Test Facility test planning of the absorption of each material is assessed.

Laser Shearography Inspection of TPS (Thermal Protection System) Cork on RSRM (Reusable Solid Rocket Motors)

Science.gov (United States)

Lingbloom, Mike; Plaia, Jim; Newman, John

2006-01-01

Laser Shearography is a viable inspection method for detection of de-bonds and voids within the external TPS (thermal protection system) on to the Space Shuttle RSRM (reusable solid rocket motors). Cork samples with thicknesses up to 1 inch were tested at the LTI (Laser Technology Incorporated) laboratory using vacuum-applied stress in a vacuum chamber. The testing proved that the technology could detect cork to steel un-bonds using vacuum stress techniques in the laboratory environment. The next logical step was to inspect the TPS on a RSRM. Although detailed post flight inspection has confirmed that ATK Thiokol's cork bonding technique provides a reliable cork to case bond, due to the Space Shuttle Columbia incident there is a great interest in verifying bond-lines on the external TPS. This interest provided and opportunity to inspect a RSRM motor with Laser Shearography. This paper will describe the laboratory testing and RSRM testing that has been performed to date. Descriptions of the test equipment setup and techniques for data collection and detailed results will be given. The data from the test show that Laser Shearography is an effective technology and readily adaptable to inspect a RSRM.

Reliable Transport over SpaceWire for James Webb Space Telescope (JWST) Focal Plane Electronics (FPE) Network

Science.gov (United States)

Rakow, Glenn; Schnurr, Richard; Dailey, Christopher; Shakoorzadeh, Kamdin

2003-01-01

combination of requirements necessitates a redundant, fault tolerant, high- speed, low mass, low power network with a low Bit error Rate(1E-9- 1E-12). The ISIM systems team performed many studies of the various network architectures that meeting these requirements. The architecture selected uses the Spacewire protocol, with the addition of a new transport and network layer added to implement end-to-end reliable transport. The network and reliable transport mechanism must be implemented in hardware because of the high average information rate and the restriction on the ability of the detectors to buffer data due to power and size restrictions. This network and transport mechanism was designed to be compatible with existing Spacewire links and routers so that existing equipment and designs may be leveraged upon. The transport layer specification is being coordinated with European Space Agency (ESA), Spacewire Working Group and the Consultative Committee for Space Data System (CCSDS) PlK Standard Onboard Interface (SOIF) panel, with the intent of developing a standard for reliable transport for Spacewire. Changes to the protocol presented are likely since negotiations are ongoing with these groups. A block of RTL VHDL that implements a multi-port Spacewire router with an external user interface will be developed and integrated with an existing Spacewire Link design. The external user interface will be the local interface that sources and sinks packets onto and off of the network (Figure 3). The external user interface implements the network and transport layer and handles acknowledgements and re-tries of packets for reliable transport over the network. Because the design is written in RTL, it may be ported to any technology but will initially be targeted to the new Actel Accelerator series (AX) part. Each link will run at 160 Mbps and the power will be about 0.165 Watt per link worst case in the Actel AX.

Design of shipping packages to transport varying radioisotopic source materials for future space and terrestrial missions

International Nuclear Information System (INIS)

Barklay, C.D.

1995-01-01

The exploration of space will begin with manned missions to the moon and to Mars, first for scientific discoveries, then for mining and manufacturing. Because of the great financial costs of this type of exploration, it can only be accomplished through an international team effort. This unified effort must include the design, planning and, execution phases of future space missions, extending down to such activities as isotope processing, and shipping package design, fabrication, and certification. All aspects of this effort potentially involve the use of radioisotopes in some capacity, and the transportation of these radioisotopes will be impossible without a shipping package that is certified by the Nuclear Regulatory Commission or the U.S. Department of Energy for domestic shipments, and the U.S. Department of Transportation or the International Atomic Energy Agency for international shipments. To remain without the international regulatory constraints, and still support the needs of new and challenging space missions conducted within ever-shrinking budgets, shipping package concepts must be innovative. A shipping package must also be versatile enough to be reconfigured to transport the varying radioisotopic source materials that may be required to support future space and terrestrial missions. One such package is the Mound USA/9516/B(U)F. Taking into consideration the potential need to transport specific types of radioisotopes, approximations of dose rates at specific distances were determined taking into account the attenuation of dose rate with distance for varying radioisotopic source materials. As a result, it has been determined that the shipping package requirements that will be demanded by future space (and terrestrial) missions can be met by making minor modifications to the USA/9516/B(U)F. copyright 1995 American Institute of Physics

Conformal cryogenic tank trade study for reusable launch vehicles

Science.gov (United States)

Rivers, H. Kevin

1999-01-01

Future reusable launch vehicles may be lifting bodies with non-circular cross section like the proposed Lockheed-Martin VentureStar™. Current designs for the cryogenic tanks of these vehicles are dual-lobed and quad-lobed tanks which are packaged more efficiently than circular tanks, but still have low packaging efficiencies with large gaps existing between the vehicle outer mold line and the outer surfaces of the tanks. In this study, tanks that conform to the outer mold line of a non-circular vehicle were investigated. Four structural concepts for conformal cryogenic tanks and a quad-lobed tank concept were optimized for minimum weight designs. The conformal tank concepts included a sandwich tank stiffened with axial tension webs, a sandwich tank stiffened with transverse tension webs, a sandwich tank stiffened with rings and tension ties, and a sandwich tank stiffened with orthogrid stiffeners and tension ties. For each concept, geometric parameters (such as ring frame spacing, the number and spacing of tension ties or webs, and tank corner radius) and internal pressure loads were varied and the structure was optimized using a finite-element-based optimization procedure. Theoretical volumetric weights were calculated by dividing the weight of the barrel section of the tank concept and its associated frames, webs and tension ties by the volume it circumscribes. This paper describes the four conformal tank concepts and the design assumptions utilized in their optimization. The conformal tank optimization results included theoretical weights, trends and comparisons between the concepts, are also presented, along with results from the optimization of a quad-lobed tank. Also, the effects of minimum gauge values and non-optimum weights on the weight of the optimized structure are described in this paper.

Carbon Footprint in Flexible Ureteroscopy: A Comparative Study on the Environmental Impact of Reusable and Single-Use Ureteroscopes.

Science.gov (United States)

Davis, Niall F; McGrath, Shannon; Quinlan, Mark; Jack, Gregory; Lawrentschuk, Nathan; Bolton, Damien M

2018-03-01

There are no comparative assessments on the environmental impact of endourologic instruments. We evaluated and compared the environmental impact of single-use flexible ureteroscopes with reusable flexible ureteroscopes. An analysis of the typical life cycle of the LithoVue™ (Boston Scientific) single-use digital flexible ureteroscope and Olympus Flexible Video Ureteroscope (URV-F) was performed. To measure the carbon footprint, data were obtained on manufacturing of single-use and reusable flexible ureteroscopes and from typical uses obtained with a reusable scope, including repairs, replacement instruments, and ultimate disposal of both ureteroscopes. The solid waste generated (kg) and energy consumed (kWh) during each case were quantified and converted into their equivalent mass of carbon dioxide (kg of CO 2 ) released. Flexible ureteroscopic raw materials composed of plastic (90%), steel (4%), electronics (4%), and rubber (2%). The manufacturing cost of a flexible ureteroscope was 11.49 kg of CO 2 per 1 kg of ureteroscope. The weight of the single-use LithoVue and URV-F flexible ureteroscope was 0.3 and 1 kg, respectively. The total carbon footprint of the lifecycle assessment of the LithoVue was 4.43 kg of CO 2 per endourologic case. The total carbon footprint of the lifecycle of the reusable ureteroscope was 4.47 kg of CO 2 per case. The environmental impacts of the reusable flexible ureteroscope and the single-use flexible ureteroscope are comparable. Urologists should be aware that the typical life cycle of urologic instruments is a concerning source of environmental emissions.

CNTs reinforced super-hydrophobic-oleophilic electrospun polystyrene oil sorbent for enhanced sorption capacity and reusability

KAUST Repository

Wu, Jingya

2016-12-05

To meet the challenges of global oil spills and oil-water contamination, the development of a low-cost and reusable sorbents with good hydrophobicity and oleophilic nature is crucial. In this study, functionalized carbon nanotubes (CNTs) were wrapped in polystyrene (PS) polymer (PS-CNTs) and electrospun to create an effective and rigid sorbent for oil. Covalent modification and fluorination of CNTs improved their dispersibility and interfacial interaction with the polymer, resulting in a well-aligned CNTs configuration inside the porous fiber structure. Interestingly, the oil sorption process using PS-CNTs was observed to have two phases. First, the oil swiftly entered the membrane pores formed by interconnected nanofibers due to oleophilic properties of the micro-sized void. In the second phase, the oil not only moved to nano interior spaces of the fibers by capillary forces but also adsorbed on the surface of fibers where the latter was retained due to Van der Waals force. The sorption process fits well with the intra particle diffusion model. Maximum oil sorption capacity of the PS-CNTs sorbent for sunflower oil, peanut oil, and motor oils were 116, 123, and 112 g/g, respectively, which was 65% higher than that of the PS sorbent without CNTs. Overall, a significant increase in the porosity, surface area, water contact angle, and oleophilic nature was observed for the PS-CNTs composite sorbents. Not only did the PS-CNTs sorbents exhibited a promising oil sorption capacity but also showed potential for reusability, which is an important factor to be considered in determining the overall performance of the sorbent and its environmental impacts.

CNTs reinforced super-hydrophobic-oleophilic electrospun polystyrene oil sorbent for enhanced sorption capacity and reusability

KAUST Repository

Wu, Jingya; Kyoungjin An, Alicia; Guo, Jiaxin; Lee, Eui-Jong; Usman Farid, Muhammad; Jeong, Sanghyun

2016-01-01

To meet the challenges of global oil spills and oil-water contamination, the development of a low-cost and reusable sorbents with good hydrophobicity and oleophilic nature is crucial. In this study, functionalized carbon nanotubes (CNTs) were wrapped in polystyrene (PS) polymer (PS-CNTs) and electrospun to create an effective and rigid sorbent for oil. Covalent modification and fluorination of CNTs improved their dispersibility and interfacial interaction with the polymer, resulting in a well-aligned CNTs configuration inside the porous fiber structure. Interestingly, the oil sorption process using PS-CNTs was observed to have two phases. First, the oil swiftly entered the membrane pores formed by interconnected nanofibers due to oleophilic properties of the micro-sized void. In the second phase, the oil not only moved to nano interior spaces of the fibers by capillary forces but also adsorbed on the surface of fibers where the latter was retained due to Van der Waals force. The sorption process fits well with the intra particle diffusion model. Maximum oil sorption capacity of the PS-CNTs sorbent for sunflower oil, peanut oil, and motor oils were 116, 123, and 112 g/g, respectively, which was 65% higher than that of the PS sorbent without CNTs. Overall, a significant increase in the porosity, surface area, water contact angle, and oleophilic nature was observed for the PS-CNTs composite sorbents. Not only did the PS-CNTs sorbents exhibited a promising oil sorption capacity but also showed potential for reusability, which is an important factor to be considered in determining the overall performance of the sorbent and its environmental impacts.

Commercial Space Travel, Ethics and Society

Science.gov (United States)

Cox, N. L. J.

2002-01-01

For the past two decades interest in the possibilities of commercial (manned) space travel or space tourism has increased among engineers, scientists, entrepreneurs and also citizens. A continuously growing collection of papers is being published on space tourism itself and associated subjects, like new reusable launch vehicles, space habitats, space entertainment and corresponding law and regulation. Market research promises sufficient interest in tourist space travel to take off and develop into a multi billion-dollar business. The basic engineering knowledge and expertise is available to start development and designing of safe and affordable reusable vertical lift off and landing vehicles, like the Kankoh-Maru. However, many issues remain fairly untouched in literature. These include, for example, regulations, law, international agreement on space traffic control and also insurance policy. One important topic however has been barely touched upon. This concerns the ethical issues in commercial (manned) space travel, which need to be considered thoroughly, preferably before actual take off of the first regular space tourist services. The answer to the latter question comprises the major part of the paper. First, the paper deals with the issue of who wants, needs and will go to space at what stage in the development of the space tourism industry. A schematic pyramid differentiating between several community groups is made. Secondly, it discusses the way we can and should deal with our environment. Space is still fairly unspoiled, although there is a lot of (government) debris out there. Rules of the space tourist game need to be established. A few general directions are presented, for example on debris cleaning and garbage disposal. Also our right to exploit the asteroids and the moon for material is discussed. In the last part of this paper, the risks involved with the harsh environment of space are considered. Is it safe and responsible to eject people into outer

An assessment of advanced displays and controls technology applicable to future space transportation systems

Science.gov (United States)

Hatfield, Jack J.; Villarreal, Diana

1990-01-01

The topic of advanced display and control technology is addressed along with the major objectives of this technology, the current state of the art, major accomplishments, research programs and facilities, future trends, technology issues, space transportation systems applications and projected technology readiness for those applications. The holes that may exist between the technology needs of the transportation systems versus the research that is currently under way are addressed, and cultural changes that might facilitate the incorporation of these advanced technologies into future space transportation systems are recommended. Some of the objectives are to reduce life cycle costs, improve reliability and fault tolerance, use of standards for the incorporation of advancing technology, and reduction of weight, volume and power. Pilot workload can be reduced and the pilot's situational awareness can be improved, which would result in improved flight safety and operating efficiency. This could be accomplished through the use of integrated, electronic pictorial displays, consolidated controls, artificial intelligence, and human centered automation tools. The Orbiter Glass Cockpit Display is an example examined.

Formaldehyde in reusable protective gloves.

Science.gov (United States)

Pontén, Ann

2006-05-01

Due to the clinical findings in a single patient's case, formaldehyde was suspected to be present in clinically relevant levels in reusable protective gloves. Therefore, 9 types of gloves were investigated with the semi-quantitative chromotropic acid method. It was found that 6/9 gloves emitted some formaldehyde and that 4/9 gloves emitted > or =40 microg of formaldehyde. Most of the formaldehyde was found on the inside of the gloves. To get an indication of the clinical relevance, a comparison with a protective cream declared to contain the formaldehyde-releasing agent diazolidinyl urea was performed by comparing areas of gloves with areas of cream layers with thickness 1-2 mg/cm(2). It was found that the amounts of formaldehyde emitted from the gloves might be in the same range as emitted from a layer of cream.

A Common Communications, Navigation and Surveillance Infrastructure for Accommodating Space Vehicles in the Next Generation Air Transportation System

Science.gov (United States)

VanSuetendael, RIchard; Hayes, Alan; Birr, Richard

2008-01-01

Suborbital space flight and space tourism are new potential markets that could significantly impact the National Airspace System (NAS). Numerous private companies are developing space flight capabilities to capture a piece of an emerging commercial space transportation market. These entrepreneurs share a common vision that sees commercial space flight as a profitable venture. Additionally, U.S. space exploration policy and national defense will impose significant additional demands on the NAS. Air traffic service providers must allow all users fair access to limited airspace, while ensuring that the highest levels of safety, security, and efficiency are maintained. The FAA's Next Generation Air Transportation System (NextGen) will need to accommodate spacecraft transitioning to and from space through the NAS. To accomplish this, space and air traffic operations will need to be seamlessly integrated under some common communications, navigation and surveillance (CNS) infrastructure. As part of NextGen, the FAA has been developing the Automatic Dependent Surveillance Broadcast (ADS-B) which utilizes the Global Positioning System (GPS) to track and separate aircraft. Another key component of NextGen, System-Wide Information Management/ Network Enabled Operations (SWIM/NEO), is an open architecture network that will provide NAS data to various customers, system tools and applications. NASA and DoD are currently developing a space-based range (SBR) concept that also utilizes GPS, communications satellites and other CNS assets. The future SBR will have very similar utility for space operations as ADS-B and SWIM has for air traffic. Perhaps the FAA, NASA, and DoD should consider developing a common space-based CNS infrastructure to support both aviation and space transportation operations. This paper suggests specific areas of research for developing a CNS infrastructure that can accommodate spacecraft and other new types of vehicles as an integrated part of NextGen.

再使用ロケットスペース・プレーンの遷・超・極超音速流CFD解析

OpenAIRE

Yamamoto, Yukimitsu; Ito, Ryozo; 山本　行光; 伊藤　良三

1999-01-01

In order to evaluate aerodynamic characteristics of future SSTO (Single Stage To Orbit) space transport vehicles, CFD (Computational Fluid Dynamics) analysis was conducted from transonic to hypersonic speed for two reusable rockets and hypersonic flow computations including real gas effects, were made for a space plane. Comparisons with AEDC (Arnold Engineering Development Center) hypersonic wind tunnel experiment were made for the latter space plane analysis. In the present CFD works, geomet...

Simple and reusable fibre-to-chip interconnect with adjustable coupling eficiency

NARCIS (Netherlands)

Heideman, Rene; Lambeck, Paul; Parriaux, Olivier M.; Kley, Ernst-Bernhard

1997-01-01

A simple, efficient and reusable fiber-to-chip interconnect is presented. The interconnect is based on a V-groove (wet- chemically etched) in silicon, combined with a loose-mode Si3N4-channel waveguide. The loose-mode waveguide is adiabatically tapered to the integrated optical (sensor) circuitry.

A Diagnostic Approach to Increase Reusable Dinnerware Selection in a Cafeteria

Science.gov (United States)

Manuel, Jennifer C.; Sunseri, Mary Anne; Olson, Ryan; Scolari, Miranda

2007-01-01

The current project tested a diagnostic approach to selecting interventions to increase patron selection of reusable dinnerware in a cafeteria. An assessment survey, completed by a sample of 43 patrons, suggested that the primary causes of wasteful behavior were (a) environmental arrangement of dinnerware options and (b) competing motivational…

Nano-Fe 3 O 4 /O 2 : Green, Magnetic and Reusable Catalytic ...

African Journals Online (AJOL)

, efficient, heterogeneous and reusable catalytic system for the synthesis of benzimidazoles via the reactions of o-phenylenediamine (1 eq) with aryl aldehydes (1 eq) in excellentyields (85–97 %) and short reaction times (30–100 min) with a ...

Space Van system update

Science.gov (United States)

Cormier, Len

1992-07-01

The Space Van is a proposed commercial launch vehicle that is designed to carry 1150 kg to a space-station orbit for a price of $1,900,000 per flight in 1992 dollars. This price includes return on preoperational investment. Recurring costs are expected to be about $840,000 per flight. The Space Van is a fully reusable, assisted-single-stage-to orbit system. The most innovative new feature of the Space Van system is the assist-stage concept. The assist stage uses only airbreathing engines for vertical takeoff and vertical landing in the horizontal attitude and for launching the rocket-powered orbiter stage at mach 0.8 and an altitude of about 12 km. The primary version of the orbiter is designed for cargo-only without a crew. However, a passenger version of the Space Van should be able to carry a crew of two plus six passengers to a space-station orbit. Since the Space Van is nearly single-stage, performance to polar orbit drops off significantly. The cargo version should be capable of carrying 350 kg to a 400-km polar orbit. In the passenger version, the Space Van should be able to carry two crew members - or one crew member plus a passenger.

Space charge compensation on the low energy beam transport of Linac4

CERN Document Server

AUTHOR|(SzGeCERN)733270; Scrivens, Richard; Jesus Castillo, Santos

Part of the upgrade program in the injector chains of the CERN accelerator complex is the replacement of the the proton accelerator Linac2 for the brand new Linac4 which will accelerate H$^-$ and its main goal is to increase the beam intensity in the next sections of the LHC accelerator chain. The Linac4 is now under commissioning and will use several ion sources to produce high intensity unbunched H$^-$ beams with different properties, and the low energy beam transport (LEBT) is the system in charge of match all these different beams to the Radio frequency quadrupole (RFQ). The space charge forces that spread the beam ions apart of each other and cause emittance growth limits the maximum intensity that can be transported in the LEBT, but the space charge of intense unbunched ion beams can be compensated by the generated ions by the impact ionization of the residual gas, which creates a source of secondary particles inside the beam pipe. For negative ion beams, the effect of the beam electric field is to ex...

Space Transportation System Liftoff Debris Mitigation Process Overview

Science.gov (United States)

Mitchell, Michael; Riley, Christopher

2011-01-01

Liftoff debris is a top risk to the Space Shuttle Vehicle. To manage the Liftoff debris risk, the Space Shuttle Program created a team with in the Propulsion Systems Engineering & Integration Office. The Shutt le Liftoff Debris Team harnesses the Systems Engineering process to i dentify, assess, mitigate, and communicate the Liftoff debris risk. T he Liftoff Debris Team leverages off the technical knowledge and expe rtise of engineering groups across multiple NASA centers to integrate total system solutions. These solutions connect the hardware and ana lyses to identify and characterize debris sources and zones contribut ing to the Liftoff debris risk. The solutions incorporate analyses sp anning: the definition and modeling of natural and induced environmen ts; material characterizations; statistical trending analyses, imager y based trajectory analyses; debris transport analyses, and risk asse ssments. The verification and validation of these analyses are bound by conservative assumptions and anchored by testing and flight data. The Liftoff debris risk mitigation is managed through vigilant collab orative work between the Liftoff Debris Team and Launch Pad Operation s personnel and through the management of requirements, interfaces, r isk documentation, configurations, and technical data. Furthermore, o n day of launch, decision analysis is used to apply the wealth of ana lyses to case specific identified risks. This presentation describes how the Liftoff Debris Team applies Systems Engineering in their proce sses to mitigate risk and improve the safety of the Space Shuttle Veh icle.

Reusable LH2 tank technology demonstration through ground test

Science.gov (United States)

Bianca, C.; Greenberg, H. S.; Johnson, S. E.

1995-01-01

The paper presents the project plan to demonstrate, by March 1997, the reusability of an integrated composite LH2 tank structure, cryogenic insulation, and thermal protection system (TPS). The plan includes establishment of design requirements and a comprehensive trade study to select the most suitable Reusable Hydrogen Composite Tank system (RHCTS) within the most suitable of 4 candidate structural configurations. The 4 vehicles are winged body with the capability to deliver 25,000 lbs of payload to a circular 220 nm, 51.6 degree inclined orbit (also 40,000 lbs to a 28.5 inclined 150 nm orbit). A prototype design of the selected RHCTS is established to identify the construction, fabrication, and stress simulation and test requirements necessary in an 8 foot diameter tank structure/insulation/TPS test article. A comprehensive development test program supports the 8 foot test article development and involves the composite tank itself, cryogenic insulation, and integrated tank/insulation/TPS designs. The 8 foot diameter tank will contain the integrated cryogenic insulation and TPS designs resulting from this development and that of the concurrent lightweight durable TPS program. Tank ground testing will include 330 cycles of LH2 filling, pressurization, body loading, depressurization, draining, and entry heating.

Space-charge limits on the transport of ion beams in a long alternating gradient system

International Nuclear Information System (INIS)

Tiefenback, M.G.

1986-11-01

We have experimentally studied the space-charge-dominated transport of ion beams in an alternating-gradient channel, without acceleration. We parameterize the focusing strength in terms of the zero-current ''betatron'' oscillation phase advance rate, σ 0 (degrees per focusing period). We have investigated the conditions for ''stability'', defined as the constancy of the total current and phase space area of the beam during transport. We find that the beam may be transported with neither loss of current nor growth in phase area if σ 0 0 . In this regime, the space-charge repulsive force can counter 98-99% of the externally applied focusing field, and the oscillation frequency of the beam particles can be depressed by self-forces to almost a factor of 10 below the zero-current value, limited only by the optical quality of our ion source. For σ 0 > 90 0 , we find that collective interactions bound the maintainable density of the beam, and we present a simple, semi-empirical characterization for stability, within our ability to distinguish the growth rate from zero in our apparatus. Our channel comprises 87 quadrupole lenses, 5 of which are used to prepare the beam for injection into the non-azimuthally-symmetric focusing channel

Effect of space structures against development of transport infrastructure in Banda Aceh by using the concept of transit oriented development

Science.gov (United States)

Noer, Fadhly; Matondang, A. Rahim; Sirojuzilam, Saleh, Sofyan M.

2017-11-01

Due to the shifting of city urban development causing the shift of city services center, so there is a change in space pattern and space structure in Banda Aceh, then resulting urban sprawl which can lead to congestion problem occurs on the arterial road in Banda Aceh, it can be seen from the increasing number of vehicles per year by 6%. Another issue occurs by urban sprawl is not well organized of settlement due to the uncontrolled use of space so that caused grouping or the differences in socioeconomic strata that can impact to the complexity of population mobility problem. From this background problem considered to be solved by a concept that is Transit Oriented Development (TOD), that is a concept of transportation development in co-operation with spatial. This research will get the model of transportation infrastructure development with TOD concept that can handle transportation problem in Banda Aceh, due to change of spatial structure, and to find whether TOD concept can use for the area that has a population in medium density range. The result that is obtained equation so the space structure is: Space Structure = 0.520 + 0.206X3 + 0.264X6 + 0.100X7 and Transportation Infrastructure Development = -1.457 + 0.652X1 + 0.388X5 + 0.235X6 + 0.222X7 + 0.327X8, So results obtained with path analysis method obtained variable influences, node ratio, network connectivity, travel frequency, travel destination, travel cost, and travel time, it has a lower value when direct effect with transportation infrastructure development, but if the indirect effect through the structure of space has a greater influence, can be seen from spatial structure path scheme - transportation infrastructure development.

Systems aspects of a space nuclear reactor power system

Science.gov (United States)

Jaffe, L.; Fujita, T.; Beatty, R.; Bhandari, P.; Chow, E.; Deininger, W.; Ewell, R.; Grossman, M.; Bloomfield, H.; Heller, J.

1988-01-01

Various system aspects of a 300-kW nuclear reactor power system for spacecraft have been investigated. Special attention is given to the cases of a reusable OTV and a space-based radar. It is demonstrated that the stowed length of the power system is important to mission design, and that orbital storage for months to years may be needed for missions involving orbital assembly.

Finite-difference solution of the space-angle-lethargy-dependent slowing-down transport equation

Energy Technology Data Exchange (ETDEWEB)

Matausek, M V [Boris Kidric Vinca Institute of Nuclear Sciences, Vinca, Belgrade (Yugoslavia)

1972-07-01

A procedure has been developed for solving the slowing-down transport equation for a cylindrically symmetric reactor system. The anisotropy of the resonance neutron flux is treated by the spherical harmonics formalism, which reduces the space-angle-Iethargy-dependent transport equation to a matrix integro-differential equation in space and lethargy. Replacing further the lethargy transfer integral by a finite-difference form, a set of matrix ordinary differential equations is obtained, with lethargy-and space dependent coefficients. If the lethargy pivotal points are chosen dense enough so that the difference correction term can be ignored, this set assumes a lower block triangular form and can be solved directly by forward block substitution. As in each step of the finite-difference procedure a boundary value problem has to be solved for a non-homogeneous system of ordinary differential equations with space-dependent coefficients, application of any standard numerical procedure, for example, the finite-difference method or the method of adjoint equations, is too cumbersome and would make the whole procedure practically inapplicable. A simple and efficient approximation is proposed here, allowing analytical solution for the space dependence of the spherical-harmonics flux moments, and hence the derivation of the recurrence relations between the flux moments at successive lethargy pivotal points. According to the procedure indicated above a computer code has been developed for the CDC -3600 computer, which uses the KEDAK nuclear data file. The space and lethargy distribution of the resonance neutrons can be computed in such a detailed fashion as the neutron cross-sections are known for the reactor materials considered. The computing time is relatively short so that the code can be efficiently used, either autonomously, or as part of some complex modular scheme. Typical results will be presented and discussed in order to prove and illustrate the applicability of the

Reusable, tamper-indicating seal

International Nuclear Information System (INIS)

Ryan, M.J.

1978-01-01

A reusable, tamper-indicating seal is comprised of a drum confined within a fixed body and rotatable in one direction therewithin, the top of the drum constituting a tray carrying a large number of small balls of several different colors. The fixed body contains parallel holes for looping a seal wire therethrough. The base of the drums carries cams adapted to coact with cam followers to lock the wire within the seal at one angular position of the drum. A channel in the fixed body, visible from outside the seal, adjacent the tray constitutes a segregated location for a small plurality of the colored balls. A spring in the tray forces colored balls into the segregated location at one angular position of the drum, further rotation securing the balls in position and the wires in the seal. A wedge-shaped plough removes the balls from the segregated location, at a different angular position of the drum, the wire being unlocked at the same postion. A new pattern of colored balls will appear in the segregated location when the seal is relocked

Reusable Software Usability Specifications for mHealth Applications.

Science.gov (United States)

Cruz Zapata, Belén; Fernández-Alemán, José Luis; Toval, Ambrosio; Idri, Ali

2018-01-25

One of the key factors for the adoption of mobile technologies, and in particular of mobile health applications, is usability. A usable application will be easier to use and understand by users, and will improve user's interaction with it. This paper proposes a software requirements catalog for usable mobile health applications, which can be used for the development of new applications, or the evaluation of existing ones. The catalog is based on the main identified sources in literature on usability and mobile health applications. Our catalog was organized according to the ISO/IEC/IEEE 29148:2011 standard and follows the SIREN methodology to create reusable catalogs. The applicability of the catalog was verified by the creation of an audit method, which was used to perform the evaluation of a real app, S Health, application created by Samsung Electronics Co. The usability requirements catalog, along with the audit method, identified several usability flaws on the evaluated app, which scored 83%. Some flaws were detected in the app related to the navigation pattern. Some more issues related to the startup experience, empty screens or writing style were also found. The way a user navigates through an application improves or deteriorates user's experience with the application. We proposed a reusable usability catalog and an audit method. This proposal was used to evaluate a mobile health application. An audit report was created with the usability issues identified on the evaluated application.

CLARAty: Challenges and Steps Toward Reusable Robotic Software

Directory of Open Access Journals (Sweden)

Richard Madison

2008-11-01

Full Text Available We present in detail some of the challenges in developing reusable robotic software. We base that on our experience in developing the CLARAty robotics software, which is a generic object-oriented framework used for the integration of new algorithms in the areas of motion control, vision, manipulation, locomotion, navigation, localization, planning and execution. CLARAty was adapted to a number of heterogeneous robots with different mechanisms and hardware control architectures. In this paper, we also describe how we addressed some of these challenges in the development of the CLARAty software.

CLARAty: Challenges and Steps toward Reusable Robotic Software

Directory of Open Access Journals (Sweden)

Issa A.D. Nesnas

2006-03-01

Full Text Available We present in detail some of the challenges in developing reusable robotic software. We base that on our experience in developing the CLARAty robotics software, which is a generic object-oriented framework used for the integration of new algorithms in the areas of motion control, vision, manipulation, locomotion, navigation, localization, planning and execution. CLARAty was adapted to a number of heterogeneous robots with different mechanisms and hardware control architectures. In this paper, we also describe how we addressed some of these challenges in the development of the CLARAty software.

The Development of Reusable Luggage Tag with the Internet of Things for Mobile Tracking and Environmental Sustainability

Directory of Open Access Journals (Sweden)

Eugene Y. C. Wong

2016-12-01

Full Text Available With more than two billion passengers worldwide travelling by air each year, vast amounts of lost luggage and disposable paper adhesive luggage tags are pushing the aviation industry to improve luggage tracking and reduce the one-off adhesive luggage paper tags. This paper reviews the current application of Radio Frequency Identification (RFID in the luggage handling system and proposes the Internet of Things’ (IoT development of the reusable luggage tag to facilitate aviation luggage handling, the tracking process and environmental conservation. A framework of IoT and its RFID components for the proposed reusable tag are presented. An integrated cyber-physical system, including a database management system and mobile app, for the reusable luggage tag is developed. Future studies will enhance the methodology of integrating the retail system, luggage tag, airport check-in counter, luggage handling system, aircraft, and the destination airport through the use of the tag, readers, antenna, and mobile devices.

Space transfer vehicle concepts and requirements, volume 2, book 1

Science.gov (United States)

1991-01-01

The objective of the systems engineering task was to develop and implement an approach that would generate the required study products as defined by program directives. This product list included a set of system and subsystem requirements, a complete set of optimized trade studies and analyses resulting in a recommended system configuration, and the definition of an integrated system/technology and advanced development growth path. A primary ingredient in the approach was the TQM philosophy stressing job quality from the inception. Included throughout the Systems Engineering, Programmatics, Concepts, Flight Design, and Technology sections are data supporting the original objectives as well as supplemental information resulting from program activities. The primary result of the analyses and studies was the recommendation of a single propulsion stage Lunar Transportation System (LTS) configuration that supports several different operations scenarios with minor element changes. This concept has the potential to support two additional scenarios with complex element changes. The space based LTS concept consists of three primary configurations--Piloted, Reusable Cargo, and Expendable Cargo.

Spatial model of convective solute transport in brain extracellular space does not support a "glymphatic" mechanism.

Science.gov (United States)

Jin, Byung-Ju; Smith, Alex J; Verkman, Alan S

2016-12-01

A "glymphatic system," which involves convective fluid transport from para-arterial to paravenous cerebrospinal fluid through brain extracellular space (ECS), has been proposed to account for solute clearance in brain, and aquaporin-4 water channels in astrocyte endfeet may have a role in this process. Here, we investigate the major predictions of the glymphatic mechanism by modeling diffusive and convective transport in brain ECS and by solving the Navier-Stokes and convection-diffusion equations, using realistic ECS geometry for short-range transport between para-arterial and paravenous spaces. Major model parameters include para-arterial and paravenous pressures, ECS volume fraction, solute diffusion coefficient, and astrocyte foot-process water permeability. The model predicts solute accumulation and clearance from the ECS after a step change in solute concentration in para-arterial fluid. The principal and robust conclusions of the model are as follows: (a) significant convective transport requires a sustained pressure difference of several mmHg between the para-arterial and paravenous fluid and is not affected by pulsatile pressure fluctuations; (b) astrocyte endfoot water permeability does not substantially alter the rate of convective transport in ECS as the resistance to flow across endfeet is far greater than in the gaps surrounding them; and (c) diffusion (without convection) in the ECS is adequate to account for experimental transport studies in brain parenchyma. Therefore, our modeling results do not support a physiologically important role for local parenchymal convective flow in solute transport through brain ECS. © 2016 Jin et al.

In-Space Transportation for NASA's Evolvable Mars Campaign

Science.gov (United States)

Percy, Thomas K.; McGuire, Melissa; Polsgrove, Tara

2015-01-01

As the nation embarks on a new and bold journey to Mars, significant work is being done to determine what that mission and those architectural elements will look like. The Evolvable Mars Campaign, or EMC, is being evaluated as a potential approach to getting humans to Mars. Built on the premise of leveraging current technology investments and maximizing element commonality to reduce cost and development schedule, the EMC transportation architecture is focused on developing the elements required to move crew and equipment to Mars as efficiently and effectively as possible both from a performance and a programmatic standpoint. Over the last 18 months the team has been evaluating potential options for those transportation elements. One of the key aspects of the EMC is leveraging investments being made today in missions like the Asteroid Redirect Mission (ARM) mission using derived versions of the Solar Electric Propulsion (SEP) propulsion systems and coupling them with other chemical propulsion elements that maximize commonality across the architecture between both transportation and Mars operations elements. This paper outlines the broad trade space being evaluated including the different technologies being assessed for transportation elements and how those elements are assembled into an architecture. Impacts to potential operational scenarios at Mars are also investigated. Trades are being made on the size and power level of the SEP vehicle for delivering cargo as well as the size of the chemical propulsion systems and various mission aspects including Inspace assembly and sequencing. Maximizing payload delivery to Mars with the SEP vehicle will better support the operational scenarios at Mars by enabling the delivery of landers and habitation elements that are appropriately sized for the mission. The purpose of this investigation is not to find the solution but rather a suite of solutions with potential application to the challenge of sending cargo and crew to Mars

Poorly processed reusable surface disinfection tissue dispensers may be a source of infection.

Science.gov (United States)

Kampf, Günter; Degenhardt, Stina; Lackner, Sibylle; Jesse, Katrin; von Baum, Heike; Ostermeyer, Christiane

2014-01-21

Reusable surface disinfectant tissue dispensers are used in hospitals in many countries because they allow immediate access to pre-soaked tissues for targeted surface decontamination. On the other hand disinfectant solutions with some active ingredients may get contaminated and cause outbreaks. We determined the frequency of contaminated surface disinfectant solutions in reusable dispensers and the ability of isolates to multiply in different formulations. Reusable tissue dispensers with different surface disinfectants were randomly collected from healthcare facilities. Solutions were investigated for bacterial contamination. The efficacy of two surface disinfectants was determined in suspension tests against two isolated species directly from a contaminated solution or after 5 passages without selection pressure in triplicate. Freshly prepared use solutions were contaminated to determine survival of isolates. 66 dispensers containing disinfectant solutions with surface-active ingredients were collected in 15 healthcare facilities. 28 dispensers from nine healthcare facilities were contaminated with approximately 107 cells per mL of Achromobacter species 3 (9 hospitals), Achromobacter xylosoxidans or Serratia marcescens (1 hospital each). In none of the hospitals dispenser processing had been adequately performed. Isolates regained susceptibility to the disinfectants after five passages without selection pressure but were still able to multiply in different formulations from different manufacturers at room temperature within 7 days. Neglecting adequate processing of surface disinfectant dispensers has contributed to frequent and heavy contamination of use-solutions based on surface active ingredients. Tissue dispenser processing should be taken seriously in clinical practice.

The Reusable Launch Vehicle Technology Program and the X-33 Advanced Technology Demonstrator

Science.gov (United States)

Cook, Stephen A.

1995-01-01

The goal of the Reusable Launch Vehicle (RLV) technology program is formulated, and the primary objectives of RLV are listed. RLV technology program implementation phases are outlined. X-33 advanced technology demonstrator is described. Program management is addressed.

Reusable Areas of Clinically Used Ventilators Carry Low Numbers of Aerobic Bacteria

Directory of Open Access Journals (Sweden)

Elizabeth Anne Gonzalez

2014-12-01

Full Text Available Ventilator associated pneumonia (VAP remains a serious problem for critically ill patients. We swabbed nine reusable areas on 20 clinically-used ventilators from a VA Hospital shortly after they had been removed from patients and identified bacterial isolates. No bacteria were isolated from most of the samples and of the samples that did grow bacteria, the majority of those had fewer than 10 colonies. The bacteria that were isolated were primarily non-pathogenic Gram-positive skin flora. Of the 20 ventilators swabbed, only one cultured bacteria associated with nosocomial infections: methicillin-resistant S.aureus. The most commonly contaminated areas were those most likely to be touched by healthcare professionals: the power button and the screen. The areas in closest proximity to the patients, the inspiratory and expiratory ports were the least often contaminated areas. Overall, very few bacteria were transferred to the reusable areas of the ventilators following clinical use.

Reusable Areas of Clinically Used Ventilators Carry Low Numbers of Aerobic Bacteria

Directory of Open Access Journals (Sweden)

Elizabeth Anne Gonzalez

2014-10-01

Full Text Available Ventilator associated pneumonia (VAP remains a serious problem for critically ill patients. We swabbed nine reusable areas on 20 clinically-used ventilators from a VA Hospital shortly after they had been removed from patients and identified bacterial isolates. No bacteria were isolated from most of the samples and of the samples that did grow bacteria, the majority of those had fewer than 10 colonies. The bacteria that were isolated were primarily non-pathogenic Gram-positive skin flora. Of the 20 ventilators swabbed, only one cultured bacteria associated with nosocomial infections: methicillin-resistant S.aureus. The most commonly contaminated areas were those most likely to be touched by healthcare professionals: the power button and the screen. The areas in closest proximity to the patients, the inspiratory and expiratory ports were the least often contaminated areas. Overall, very few bacteria were transferred to the reusable areas of the ventilators following clinical use.

Heat Transfer Measurement and Modeling in Rigid High-Temperature Reusable Surface Insulation Tiles

Science.gov (United States)

Daryabeigi, Kamran; Knutson, Jeffrey R.; Cunnington, George R.

2011-01-01

Heat transfer in rigid reusable surface insulations was investigated. Steady-state thermal conductivity measurements in a vacuum were used to determine the combined contribution of radiation and solid conduction components of heat transfer. Thermal conductivity measurements at higher pressures were then used to estimate the effective insulation characteristic length for gas conduction modeling. The thermal conductivity of the insulation can then be estimated at any temperature and pressure in any gaseous media. The methodology was validated by comparing estimated thermal conductivities with published data on a rigid high-temperature silica reusable surface insulation tile. The methodology was also applied to the alumina enhanced thermal barrier tiles. Thermal contact resistance for thermal conductivity measurements on rigid tiles was also investigated. A technique was developed to effectively eliminate thermal contact resistance on the rigid tile s cold-side surface for the thermal conductivity measurements.

Space Transportation System Availability Requirements and Its Influencing Attributes Relationships

Science.gov (United States)

Rhodes, Russel E.; Adams, TImothy C.

2008-01-01

It is essential that management and engineering understand the need for an availability requirement for the customer's space transportation system as it enables the meeting of his needs, goal, and objectives. There are three types of availability, e.g., operational availability, achieved availability, or inherent availability. The basic definition of availability is equal to the mean uptime divided by the sum of the mean uptime plus the mean downtime. The major difference is the inclusiveness of the functions within the mean downtime and the mean uptime. This paper will address tIe inherent availability which only addresses the mean downtime as that mean time to repair or the time to determine the failed article, remove it, install a replacement article and verify the functionality of the repaired system. The definitions of operational availability include the replacement hardware supply or maintenance delays and other non-design factors in the mean downtime. Also with inherent availability the mean uptime will only consider the mean time between failures (other availability definitions consider this as mean time between maintenance - preventive and corrective maintenance) that requires the repair of the system to be functional. It is also essential that management and engineering understand all influencing attributes relationships to each other and to the resultant inherent availability requirement. This visibility will provide the decision makers with the understanding necessary to place constraints on the design definition for the major drivers that will determine the inherent availability, safety, reliability, maintainability, and the life cycle cost of the fielded system provided the customer. This inherent availability requirement may be driven by the need to use a multiple launch approach to placing humans on the moon or the desire to control the number of spare parts required to support long stays in either orbit or on the surface of the moon or mars. It is

Allocating city space to multiple transportation modes: A new modeling approach consistent with the physics of transport

OpenAIRE

Gonzales, Eric J.; Geroliminis, Nikolas; Cassidy, Michael J.; Daganzo, Carlos F.

2008-01-01

A macroscopic modeling approach is proposed for allocating a city’s road space among competing transport modes. In this approach, a city or neighborhood street network is viewed as a reservoir with aggregated traffic. Taking the number of vehicles (accumulation) in a reservoir as input, we show how one can reliably predict system performance in terms of person and vehicle hours spent in the system and person and vehicle kilometers traveled. The approach is used here to unveil two important ...

End-to-End Trajectory for Conjunction Class Mars Missions Using Hybrid Solar-Electric/Chemical Transportation System

Science.gov (United States)

Chai, Patrick R.; Merrill, Raymond G.; Qu, Min

2016-01-01

NASA's Human Spaceflight Architecture Team is developing a reusable hybrid transportation architecture in which both chemical and solar-electric propulsion systems are used to deliver crew and cargo to exploration destinations. By combining chemical and solar-electric propulsion into a single spacecraft and applying each where it is most effective, the hybrid architecture enables a series of Mars trajectories that are more fuel efficient than an all chemical propulsion architecture without significant increases to trip time. The architecture calls for the aggregation of exploration assets in cislunar space prior to departure for Mars and utilizes high energy lunar-distant high Earth orbits for the final staging prior to departure. This paper presents the detailed analysis of various cislunar operations for the EMC Hybrid architecture as well as the result of the higher fidelity end-to-end trajectory analysis to understand the implications of the design choices on the Mars exploration campaign.

Design and management of networks with fixed transportation costs

OpenAIRE

Lange, Jean-Charles

2010-01-01

Reusable packages are logistic items used for the shipments of goods from a producer to its customers and which, once the goods have been consumed by the customers, are to be returned to the producer. This doctoral thesis addresses the strategic design and the operational management of large independent reverse networks for their return flows when fixed transportation costs apply. At the strategic level, we identify the economic logic by which the allocation of the customers should be made...

REUSABILITY OF BOND ELUT CERTIFY COLUMNS FOR THE EXTRACTION OF DRUGS FROM PLASMA

NARCIS (Netherlands)

CHEN, XH; FRANKE, JP; WIJSBEEK, J; DEZEEUW, RA

1993-01-01

The reusability of Bond Elut Certify columns for the extraction of toxicologically relevant drugs from plasma has been evaluated. Pentobarbital, hexobarbital, mepivacaine, trimipramine and clonazepam were selected as test drugs to represent various classes of drugs. The columns were regenerated

Towards a DNA Nanoprocessor: Reusable Tile-Integrated DNA Circuits.

Science.gov (United States)

Gerasimova, Yulia V; Kolpashchikov, Dmitry M

2016-08-22

Modern electronic microprocessors use semiconductor logic gates organized on a silicon chip to enable efficient inter-gate communication. Here, arrays of communicating DNA logic gates integrated on a single DNA tile were designed and used to process nucleic acid inputs in a reusable format. Our results lay the foundation for the development of a DNA nanoprocessor, a small and biocompatible device capable of performing complex analyses of DNA and RNA inputs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

FFTF radioactive solid waste handling and transport

International Nuclear Information System (INIS)

Thomson, J.D.

1982-01-01

The equipment necessary for the disposal of radioactive solid waste from the Fast Flux Test Facility (FFTF) is scheduled to be available for operation in late 1982. The plan for disposal of radioactive waste from FFTF will utilize special waste containers, a reusable Solid Waste Cask (SWC) and a Disposable Solid Waste Cask (DSWC). The SWC will be used to transport the waste from the Reactor Containment Building to a concrete and steel DSWC. The DSWC will then be transported to a burial site on the Hanford Reservation near Richland, Washington. Radioactive solid waste generated during the operation of the FFTF consists of activated test assembly hardware, reflectors, in-core shim assemblies and control rods. This radioactive waste must be cleaned (sodium removed) prior to disposal. This paper provides a description of the solid waste disposal process, and the casks and equipment used for handling and transport

Reusable locking tube in a reconstitutable fuel assembly

International Nuclear Information System (INIS)

Shallenberger, J.M.; Ferlan, S.J.

1987-01-01

This patent describes a reconstitutable fuel assembly including a top nozzle with an adapter plate having an interior wall forming at least one passageway, at least one guide thimble with an upper end portion, and an attaching structure having an outer socket formed by a circumferential groove defined in the adapter plate passageway wall and opening into the passageway and an inner socket formed by a circumferential bulge and at least one longitudinal slot defined in the upper end portion of the guide thimble. The circumferential bulge is capable of seating within the circumferential groove, an improved reusable tube for releasably locking the inner socket of the guide thimble upper end portion in locking engagement within the outer socket of the adapter plate passageway when the circumferential bulge is seated within the circumferential groove. The reusable tube comprises: (a) an elongated hollow tubular body capable of insertion within the adapter plate passageway and guide thimble upper end portion to a locking position therein such that the circumferential bulge of the inner socket is maintained seated in the locking engagement with the circumferential groove of the outer socket; and (b) at least a pair of dimples performed on the exterior of the tubular body prior to insertion of the body in the guide thimble upper end portion and to the locking position, the dimples being performed and configured to increase the thickness of the tubular body in relation to the remainder of the tubular body. The dimples are substantially resisting resilient yielding in relation to the remainder of the tubular body

An Analysis and Review of Measures and Relationships in Space Transportation Affordability

Science.gov (United States)

Zapata, Edgar; McCleskey, Carey

2014-01-01

The affordability of transportation to or from space is of continued interest across numerous and diverse stakeholders in our aerospace industry. Such an important metric as affordability deserves a clear understanding among stakeholders about what is meant by affordability, costs, and related terms, as otherwise it's difficult to see where specific improvements are needed or where to target specific investments. As captured in the famous words of Lewis Carroll, "If you don't know where you are going, any road will get you there". As important as understanding a metric may be, with terms such as costs, prices, specific costs, average costs, marginal costs, etc., it is equally important to understand the relationship among these measures. In turn, these measures intermingle with caveats and factors that introduce more measures in need of a common understanding among stakeholders. These factors include flight rates, capability, and payload. This paper seeks to review the costs of space transportation systems and the relationships among the many factors involved in costs from the points of view of diverse decision makers. A decision maker may have an interest in acquiring a single launch considering the best price (along with other factors in their business case), or an interest in many launches over time. Alternately, a decision maker may have a specific interest in developing a space transportation system that will offer certain prices, or flight rate capability, or both, at a certain up-front cost. The question arises for the later, to reuse or to expend? As it is necessary in thinking about the future to clearly understand the past and the present, this paper will present data and graphics to assist stakeholders in visualizing trends and the current state of affairs in the launch industry. At all times, raw data will be referenced (or made available separately) alongside detailed explanations about the data, so as to avoid the confusion or misleading conclusions

CITY TRANSPORT IN BARRIER-FREE ARCHITECTURAL PLANNING SPACE FOR PEOPLE WITH LIMITED MOBILITY

Directory of Open Access Journals (Sweden)

Pryadko Igor’ Petrovich

2014-09-01

Full Text Available This paper reviews the current state of transport organization for people with limited mobility. The article evaluates the results of the actions the executive authorities of Moscow and Moscow Region take. Barrier-free space organization for disabled people and parents with prams is given a special attention. The lack of strategy in the sphere leads to considerable difficulties for people with limited ability. This problem should be solved in cooperation with the survey of other peoples' needs. The article gives examples of comfortable urban space in Sochi, Moscow, Chita, Mytishchi and analyses the ways urbanism influences people with limited abilities.

Internal Flow Simulation of Enhanced Performance Solid Rocket Booster for the Space Transportation System

Science.gov (United States)

Ahmad, Rashid A.; McCool, Alex (Technical Monitor)

2001-01-01

An enhanced performance solid rocket booster concept for the space shuttle system has been proposed. The concept booster will have strong commonality with the existing, proven, reliable four-segment Space Shuttle Reusable Solid Rocket Motors (RSRM) with individual component design (nozzle, insulator, etc.) optimized for a five-segment configuration. Increased performance is desirable to further enhance safety/reliability and/or increase payload capability. Performance increase will be achieved by adding a fifth propellant segment to the current four-segment booster and opening the throat to accommodate the increased mass flow while maintaining current pressure levels. One development concept under consideration is the static test of a "standard" RSRM with a fifth propellant segment inserted and appropriate minimum motor modifications. Feasibility studies are being conducted to assess the potential for any significant departure in component performance/loading from the well-characterized RSRM. An area of concern is the aft motor (submerged nozzle inlet, aft dome, etc.) where the altered internal flow resulting from the performance enhancing features (25% increase in mass flow rate, higher Mach numbers, modified subsonic nozzle contour) may result in increased component erosion and char. To assess this issue and to define the minimum design changes required to successfully static test a fifth segment RSRM engineering test motor, internal flow studies have been initiated. Internal aero-thermal environments were quantified in terms of conventional convective heating and discrete phase alumina particle impact/concentration and accretion calculations via Computational Fluid Dynamics (CFD) simulation. Two sets of comparative CFD simulations of the RSRM and the five-segment (IBM) concept motor were conducted with CFD commercial code FLUENT. The first simulation involved a two-dimensional axi-symmetric model of the full motor, initial grain RSRM. The second set of analyses

almaBTE : A solver of the space-time dependent Boltzmann transport equation for phonons in structured materials

Science.gov (United States)

Carrete, Jesús; Vermeersch, Bjorn; Katre, Ankita; van Roekeghem, Ambroise; Wang, Tao; Madsen, Georg K. H.; Mingo, Natalio

2017-11-01

almaBTE is a software package that solves the space- and time-dependent Boltzmann transport equation for phonons, using only ab-initio calculated quantities as inputs. The program can predictively tackle phonon transport in bulk crystals and alloys, thin films, superlattices, and multiscale structures with size features in the nm- μm range. Among many other quantities, the program can output thermal conductances and effective thermal conductivities, space-resolved average temperature profiles, and heat-current distributions resolved in frequency and space. Its first-principles character makes almaBTE especially well suited to investigate novel materials and structures. This article gives an overview of the program structure and presents illustrative examples for some of its uses. PROGRAM SUMMARY Program Title:almaBTE Program Files doi:http://dx.doi.org/10.17632/8tfzwgtp73.1 Licensing provisions: Apache License, version 2.0 Programming language: C++ External routines/libraries: BOOST, MPI, Eigen, HDF5, spglib Nature of problem: Calculation of temperature profiles, thermal flux distributions and effective thermal conductivities in structured systems where heat is carried by phonons Solution method: Solution of linearized phonon Boltzmann transport equation, Variance-reduced Monte Carlo

Space Transportation System Availability Requirements and Its Influencing Attributes Relationships

Science.gov (United States)

Rhodes, Russell E.; Adams, Timothy C.; McCleskey, Carey M.

2008-01-01

It is important that engineering and management accept the need for an availability requirement that is derived with its influencing attributes. It is the intent of this paper to provide the visibility of relationships of these major attribute drivers (variables) to each other and the resultant system inherent availability. Also important to provide bounds of the variables providing engineering the insight required to control the system's engineering solution, e.g., these influencing attributes become design requirements also. These variables will drive the need to provide integration of similar discipline functions or technology selection to allow control of the total parts count. The relationship of selecting a reliability requirement will place a constraint on parts count to achieve a given availability requirement or if allowed to increase the parts count will drive the system reliability requirement higher. They also provide the understanding for the relationship of mean repair time (or mean down time) to maintainability, e.g., accessibility for repair, and both the mean time between failure, e.g., reliability of hardware and availability. The concerns and importance of achieving a strong availability requirement is driven by the need for affordability, the choice of using the two launch solution for the single space application, or the need to control the spare parts count needed to support the long stay in either orbit or on the surface of the moon. Understanding the requirements before starting the architectural design concept will avoid considerable time and money required to iterate the design to meet the redesign and assessment process required to achieve the results required of the customer's space transportation system. In fact the impact to the schedule to being able to deliver the system that meets the customer's needs, goals, and objectives may cause the customer to compromise his desired operational goal and objectives resulting in considerable

Space Transportation System Availability Requirement and Its Influencing Attributes Relationships

Science.gov (United States)

Rhodes, Russel E.; Adams, Timothy C.; McCleskey, Carey M.

2008-01-01

It is important that engineering and management accept the need for an availability requirement that is derived with its influencing attributes. It is the intent of this paper to provide the visibility of relationships of these major attribute drivers (variables) to each other and the resultant system inherent availability. Also important to provide bounds of the variables providing engineering the insight required to control the system's engineering solution, e.g., these influencing attributes become design requirements also. These variables will drive the need to provide integration of similar discipline functions or technology selection to allow control of the total parts count. The relationship of selecting a reliability requirement will place a constraint on parts count to achieve a given availability requirement or if allowed to increase the parts count will drive the system reliability requirement higher. They also provide the understanding for the relationship of mean repair time (or mean down time) to maintainability, e.g., accessibility for repair, and both the mean time between failure, e.g., reliability of hardware and availability. The concerns and importance of achieving a strong availability requirement is driven by the need for affordability, the choice of using the two launch solution for the single space application, or the need to control the spare parts count needed to support the long stay in either orbit or on the surface of the moon. Understanding the requirements before starting the architectural design concept will avoid considerable time and money required to iterate the design to meet the redesign and assessment process required to achieve the results required of the customer's space transportation system. In fact the impact to the schedule to being able to deliver the system that meets the customer's needs, goals, and objectives may cause the customer to compromise his desired operational goal and objectives resulting in considerable

Latent Space Embedding for Retrieval in Question-Answer Archives

OpenAIRE

Padmanabhan, Deepak; Garg, Dinesh; Shevade, Shirish

2017-01-01

Community-driven Question Answering (CQA) systems such as Yahoo! Answers have become valuable sources of reusable information. CQA retrieval enables usage of historical CQA archives to solve new questions posed by users. This task has received much recent attention, with methods building upon literature from translation models, topic models, and deep learning. In this paper, we devise a CQA retrieval technique, LASER-QA, that embeds question-answer pairs within a unified latent space preservi...

Spatial model of convective solute transport in brain extracellular space does not support a “glymphatic” mechanism

Science.gov (United States)

Jin, Byung-Ju; Smith, Alex J.

2016-01-01

A “glymphatic system,” which involves convective fluid transport from para-arterial to paravenous cerebrospinal fluid through brain extracellular space (ECS), has been proposed to account for solute clearance in brain, and aquaporin-4 water channels in astrocyte endfeet may have a role in this process. Here, we investigate the major predictions of the glymphatic mechanism by modeling diffusive and convective transport in brain ECS and by solving the Navier–Stokes and convection–diffusion equations, using realistic ECS geometry for short-range transport between para-arterial and paravenous spaces. Major model parameters include para-arterial and paravenous pressures, ECS volume fraction, solute diffusion coefficient, and astrocyte foot-process water permeability. The model predicts solute accumulation and clearance from the ECS after a step change in solute concentration in para-arterial fluid. The principal and robust conclusions of the model are as follows: (a) significant convective transport requires a sustained pressure difference of several mmHg between the para-arterial and paravenous fluid and is not affected by pulsatile pressure fluctuations; (b) astrocyte endfoot water permeability does not substantially alter the rate of convective transport in ECS as the resistance to flow across endfeet is far greater than in the gaps surrounding them; and (c) diffusion (without convection) in the ECS is adequate to account for experimental transport studies in brain parenchyma. Therefore, our modeling results do not support a physiologically important role for local parenchymal convective flow in solute transport through brain ECS. PMID:27836940

Technology development for metallic hot structures in aerodynamic control surfaces of reusable launchers

NARCIS (Netherlands)

Sudmeijer, K.J.; Wentzel, C.; Lefeber, B.M.; Kloosterman, A.

2002-01-01

In this paper a summary is presented of the technology development in the Netherlands focussed on the design and development of a metallic aerodynamic control surface for the future European reusable launcher. The applied materials are mainly Oxide Dispersion Strengthened (ODS) alloys produced by

Space allowance of young goats during transportation to slaughter = Beladingsdichtheid tijdens het wegtransport van jonge geiten

NARCIS (Netherlands)

Hindle, V.A.; Reimert, H.G.M.; Werf, van der J.T.N.; Lambooij, E.

2011-01-01

Research was performed during long distance road transportations of young goats (6-8 weeks). Effects of three space allowances on physiological responses (blood parameters, heart rate and body temperature) were measured.

Technology Transfer External Metrics, Research, Success Stories, and Participation on Evaluation Team for the Reusable Launch Vehicle (RLV)

Science.gov (United States)

Trivoli, George W.

1996-01-01

This research report is divided into four sections. The first section is related to participation on the team that evaluated the proposals for the X-33 project and the Reusable Launch Vehicle (RLV) during mid-May; prior to beginning the 1996 Summer Faculty Fellowship. The second section discusses the various meetings attended related to the technology evaluation process. The third section is related to various research and evaluation activities engaged in by this researcher. The final section discusses several success stories this researcher aided in preparing. Despite the fact that this researcher is not an engineer or science faculty, invaluable knowledge and experience have been gained at MSFC. Although related to the previous summer's research, the research has been new, varied, and challenging. This researcher was fortunate to have had maximum interaction with NASA colleague, David Cockrell. It would be a privilege and honor to continue a relationship with the Technology Transfer Office. In addition, we will attempt to aid in the establishment of a continuous formalized relationship between MSFC and Jacksonville State University. Dr. David Watts, Vice President for Academic Affairs, J.S.U., is interested in having the Technology Division cooperating with MSFC in sharing information and working tech transfer inquiries. The principal benefits gained by this researcher include the opportunity to conduct research in a non-academic, real world environment. In addition, the opportunity to be involved in aiding with the decision process for the choice of the next generation of space transportation system was a once in a lifetime experience. This researcher has gained enhanced respect and understanding of MSFC/NASA staff and facilities.

Application of space-angle synthesis to two-dimensional neutral-particle transport problems of weapon physics

International Nuclear Information System (INIS)

Roberds, R.M.

1975-01-01

A space-angle synthesis (SAS) method has been developed for treating the steady-state, two-dimensional transport of neutrons and gamma rays from a point source of simulated nuclear weapon radiation in air. The method was validated by applying it to the problem of neutron transport from a point source in air over a ground interface, and then comparing the results to those obtained by DOT, a state-of-the-art, discrete-ordinates code. In the SAS method, the energy dependence of the Boltzmann transport equation was treated in the standard multigroup manner. The angular dependence was treated by expanding the flux in specially tailored trial functions and applying the method of weighted residuals which analytically integrated the transport equation over all angles. The weighted-residual approach was analogous to the conventional spherical-harmonics (P/sub N/) method with the exception that the tailored expansion allowed for more rapid convergence than a spherical-harmonics P 1 expansion and resulted in a greater degree of accuracy. The trial functions used in the expansion were odd and even combinations of selected trial solutions, the trial solutions being shaped ellipsoids which approximated the angular distribution of the neutron flux in one-dimensional space. The parameters which described the shape of the ellipsoid varied with energy group and the spatial medium, only, and were obtained from a one-dimensional discrete-ordinates calculation. Thus, approximate transport solutions were made available for all two-dimensional problems of a certain class by using tabulated parameters obtained from a single, one-dimensional calculation

Modelling informally collected quantities of bulky waste and reusable items in Austria

International Nuclear Information System (INIS)

Ramusch, R.; Pertl, A.; Scherhaufer, S.; Schmied, E.; Obersteiner, G.

2015-01-01

Highlights: • Informal collectors from Hungary collect bulky waste and reusable items in Austria. • Two methodologies were applied to estimate the informally collected quantities. • Both approaches lead to an estimation of roughly 100,000 t p.a. informally collected. • The formal Austrian system collects 72 kg/cap/yr of bulky waste, WEE & scrap metal. • Informal collection amounts to approx. 12 kg/cap/yr. - Abstract: Disparities in earnings between Western and Eastern European countries are the reason for a well-established informal sector actively involved in collection and transboundary shipment activities from Austria to Hungary. The preferred objects are reusable items and wastes within the categories bulky waste, WEEE and metals, intended to be sold on flea markets. Despite leading to a loss of recyclable resources for Austrian waste management, these informal activities may contribute to the extension of the lifetime of certain goods when they are reused in Hungary; nevertheless they are discussed rather controversially. The aim of this paper is to provide objective data on the quantities informally collected and transhipped. The unique activities of informal collectors required the development and implementation of a new set of methodologies. The concept of triangulation was used to verify results obtained by field visits, interviews and a traffic counting campaign. Both approaches lead to an estimation of approx. 100,000 t per year of reusable items informally collected in Austria. This means that in addition to the approx. 72 kg/cap/yr formally collected bulky waste, bulky waste wood, household scrap (excluding packaging) and WEEE, up to a further 12 kg/cap/yr might, in the case that informal collection is abandoned, end up as waste or in the second-hand sector

Modelling informally collected quantities of bulky waste and reusable items in Austria

Energy Technology Data Exchange (ETDEWEB)

Ramusch, R., E-mail: roland.ramusch@boku.ac.at; Pertl, A.; Scherhaufer, S.; Schmied, E.; Obersteiner, G.

2015-10-15

Highlights: • Informal collectors from Hungary collect bulky waste and reusable items in Austria. • Two methodologies were applied to estimate the informally collected quantities. • Both approaches lead to an estimation of roughly 100,000 t p.a. informally collected. • The formal Austrian system collects 72 kg/cap/yr of bulky waste, WEE & scrap metal. • Informal collection amounts to approx. 12 kg/cap/yr. - Abstract: Disparities in earnings between Western and Eastern European countries are the reason for a well-established informal sector actively involved in collection and transboundary shipment activities from Austria to Hungary. The preferred objects are reusable items and wastes within the categories bulky waste, WEEE and metals, intended to be sold on flea markets. Despite leading to a loss of recyclable resources for Austrian waste management, these informal activities may contribute to the extension of the lifetime of certain goods when they are reused in Hungary; nevertheless they are discussed rather controversially. The aim of this paper is to provide objective data on the quantities informally collected and transhipped. The unique activities of informal collectors required the development and implementation of a new set of methodologies. The concept of triangulation was used to verify results obtained by field visits, interviews and a traffic counting campaign. Both approaches lead to an estimation of approx. 100,000 t per year of reusable items informally collected in Austria. This means that in addition to the approx. 72 kg/cap/yr formally collected bulky waste, bulky waste wood, household scrap (excluding packaging) and WEEE, up to a further 12 kg/cap/yr might, in the case that informal collection is abandoned, end up as waste or in the second-hand sector.

Conceptual design of a crewed reusable space transportation system aimed at parabolic flights: stakeholder analysis, mission concept selection, and spacecraft architecture definition

Science.gov (United States)

Fusaro, Roberta; Viola, Nicole; Fenoglio, Franco; Santoro, Francesco

2017-03-01

This paper proposes a methodology to derive architectures and operational concepts for future earth-to-orbit and sub-orbital transportation systems. In particular, at first, it describes the activity flow, methods, and tools leading to the generation of a wide range of alternative solutions to meet the established goal. Subsequently, the methodology allows selecting a small number of feasible options among which the optimal solution can be found. For the sake of clarity, the first part of the paper describes the methodology from a theoretical point of view, while the second part proposes the selection of mission concepts and of a proper transportation system aimed at sub-orbital parabolic flights. Starting from a detailed analysis of the stakeholders and their needs, the major objectives of the mission have been derived. Then, following a system engineering approach, functional analysis tools as well as concept of operations techniques allowed generating a very high number of possible ways to accomplish the envisaged goals. After a preliminary pruning activity, aimed at defining the feasibility of these concepts, more detailed analyses have been carried out. Going on through the procedure, the designer should move from qualitative to quantitative evaluations, and for this reason, to support the trade-off analysis, an ad-hoc built-in mission simulation software has been exploited. This support tool aims at estimating major mission drivers (mass, heat loads, manoeuverability, earth visibility, and volumetric efficiency) as well as proving the feasibility of the concepts. Other crucial and multi-domain mission drivers, such as complexity, innovation level, and safety have been evaluated through the other appropriate analyses. Eventually, one single mission concept has been selected and detailed in terms of layout, systems, and sub-systems, highlighting also logistic, safety, and maintainability aspects.

Interconnection blocks: a method for providing reusable, rapid, multiple, aligned and planar microfluidic interconnections

DEFF Research Database (Denmark)

Sabourin, David; Snakenborg, Detlef; Dufva, Hans Martin

2009-01-01

In this paper a method is presented for creating 'interconnection blocks' that are re-usable and provide multiple, aligned and planar microfluidic interconnections. Interconnection blocks made from polydimethylsiloxane allow rapid testing of microfluidic chips and unobstructed microfluidic observ...

RPD: Reusable Pseudo-Id Distribution for a Secure and Privacy Preserving VANET

Directory of Open Access Journals (Sweden)

Sulaiman Ashraph

2013-08-01

Full Text Available In any VANET, security and privacy are the two fundamental issues. Obtaining efficient security in vehicular communication is essential without compromising privacy-preserving mechanisms. Designing a suitable protocol for VANET by having these two issues in mind is challenging because efficiency, unlinkablity and traceability are the three qualities having contradictions between them. In this paper, we introduce an efficient Reusable Pseudo-id Distribution (RPD scheme. The Trusted Authority (TA designating the Road Side Units (RSUs to generate n reusable pseudo ids and distribute them to the On Board Units (OBUs on request characterizes the proposed protocol. RSUs issue the aggregated hashes of all its valid pseudo-ids along with a symmetric shared key and a particular pseudo-id to each vehicle that enters into its coverage range. Through this the certificates attached to the messages can be eliminated and thus resulting in a significantly reduced packet size. The same anonymous keys can then be re-distributed by the RSUs episodically to other vehicles. We analyze the proposed protocol extensively to demonstrate its merits and efficiency.

Improving learning of anatomy with reusable learning objects

Directory of Open Access Journals (Sweden)

P Rad

2015-12-01

Full Text Available Introduction: The use of modern educational technologies is useful for learning, durability, sociability, and upgrading professionalism. The aim of this study was evaluating the effect of reusable learning objects on improving learning of anatomy. Methods: This was a quasi-experimental study. Fourteen (reusable learning objects RLO from different parts of anatomy of human body including thorax, abdomen, and pelvis were prepared for medical student in Yasuj University of Medical Sciences in 2009. The length of the time for RLO was between 11-22 min. Because their capacities were low, so they were easy to use with cell phone or MP4. These materials were available to the students before the classes. The mean scores of students in anatomy of human body group were compared to the medical students who were not used this method and entered the university in 2008. A questionnaire was designed by the researcher to evaluate the effect of RLO and on, content, interest and motivation, participation, preparation and attitude. Result: The mean scores of anatomy of human body of medical student who were entered the university in 2009 have been increased compare to the students in 2008, but this difference was not significant. Based on the questionnaire data, it was shown that the RLO had a positive effect on improving learning anatomy of human body (75.5% and the effective relationship (60.6%. The students were interested in using RLO (74.6%, some students (54.2% believed that this method should be replaced by lecture. Conclusion: The use of RLO could promote interests and effective communication among the students and led to increasing self-learning motivation.

A reusable suture anchor for arthroscopy psychomotor skills training.

Science.gov (United States)

Tillett, Edward D; Rogers, Rainie; Nyland, John

2003-03-01

For residents to adequately develop the early arthroscopy psychomotor skills required to better learn how to manage the improvisational situations they will encounter during actual patient cases, they need to experience sufficient practice repetitions within a contextually relevant environment. Unfortunately, the cost of suture anchors can be a practice repetition-limiting factor in learning arthroscopic knot-tying techniques. We describe a technique for creating inexpensive reusable suture anchors and provide an example of their application to repair the anterior glenoid labrum during an arthroscopy psychomotor skills laboratory training session.

Space Access for Small Satellites on the K-1

Science.gov (United States)

Faktor, L.

Affordable access to space remains a major obstacle to realizing the increasing potential of small satellites systems. On a per kilogram basis, small launch vehicles are simply too expensive for the budgets of many small satellite programs. Opportunities for rideshare with larger payloads on larger launch vehicles are still rare, given the complications associated with coordinating delivery schedules and deployment orbits. Existing contractual mechanisms are also often inadequate to facilitate the launch of multiple payload customers on the same flight. Kistler Aerospace Corporation is committed to lowering the price and enhancing the availability of space access for small satellite programs through the fully-reusable K-1 launch vehicle. Kistler has been working with a number of entities, including Astrium Ltd., AeroAstro, and NASA, to develop innovative approaches to small satellite missions. The K-1 has been selected by NASA as a Flight Demonstration Vehicle for the Space Launch Initiative. NASA has purchased the flight results during the first four K-1 launches on the performance of 13 advanced launch vehicle technologies embedded in the K-1 vehicle. On K-1 flights #2-#4, opportunities exist for small satellites to rideshare to low-earth orbit for a low-launch price. Kistler's flight demonstration contract with NASA also includes options to fly Add-on Technology Experiment flights. Opportunities exist for rideshare payloads on these flights as well. Both commercial and government customers may take advantage of the rideshare pricing. Kistler is investigating the feasibility of flying dedicated, multiple small payload missions. Such a mission would launch multiple small payloads from a single customer or small payloads from different customers. The orbit would be selected to be compatible with the requirements of as many small payload customers as possible, and make use of reusable hardware, standard interfaces (such as the existing MPAS) and verification plans

Fluid Physical and Transport Phenomena Studies aboard the International Space Station: Planned Experiments

Science.gov (United States)

Singh, Bhim S.

1999-01-01

This paper provides an overview of the microgravity fluid physics and transport phenomena experiments planned for the International Spare Station. NASA's Office of Life and Microgravity Science and Applications has established a world-class research program in fluid physics and transport phenomena. This program combines the vast expertise of the world research community with NASA's unique microgravity facilities with the objectives of gaining new insight into fluid phenomena by removing the confounding effect of gravity. Due to its criticality to many terrestrial and space-based processes and phenomena, fluid physics and transport phenomena play a central role in the NASA's Microgravity Program. Through widely publicized research announcement and well established peer-reviews, the program has been able to attract a number of world-class researchers and acquired a critical mass of investigations that is now adding rapidly to this field. Currently there arc a total of 106 ground-based and 20 candidate flight principal investigators conducting research in four major thrust areas in the program: complex flows, multiphase flow and phase change, interfacial phenomena, and dynamics and instabilities. The International Space Station (ISS) to be launched in 1998, provides the microgravity research community with a unprecedented opportunity to conduct long-duration microgravity experiments which can be controlled and operated from the Principal Investigators' own laboratory. Frequent planned shuttle flights to the Station will provide opportunities to conduct many more experiments than were previously possible. NASA Lewis Research Center is in the process of designing a Fluids and Combustion Facility (FCF) to be located in the Laboratory Module of the ISS that will not only accommodate multiple users but, allow a broad range of fluid physics and transport phenomena experiments to be conducted in a cost effective manner.

Space Shuttle Orbiter - Leading edge structural design/analysis and material allowables

Science.gov (United States)

Johnson, D. W.; Curry, D. M.; Kelly, R. E.

1986-01-01

Reinforced Carbon-Carbon (RCC), a structural composite whose development was targeted for the high temperature reentry environments of reusable space vehicles, has successfully demonstrated that capability on the Space Shuttle Orbiter. Unique mechanical properties, particularly at elevated temperatures up to 3000 F, make this material ideally suited for the 'hot' regions of multimission space vehicles. Design allowable characterization testing, full-scale development and qualification testing, and structural analysis techniques will be presented herein that briefly chart the history of the RCC material from infancy to eventual multimission certification for the Orbiter. Included are discussions pertaining to the development of the design allowable data base, manipulation of the test data into usable forms, and the analytical verification process.

Hydrogen Research for Spaceport and Space-Based Applications: Fuel Cell Projects

Science.gov (United States)

Anderson, Tim; Balaban, Canan

2008-01-01

The activities presented are a broad based approach to advancing key hydrogen related technologies in areas such as fuel cells, hydrogen production, and distributed sensors for hydrogen-leak detection, laser instrumentation for hydrogen-leak detection, and cryogenic transport and storage. Presented are the results from research projects, education and outreach activities, system and trade studies. The work will aid in advancing the state-of-the-art for several critical technologies related to the implementation of a hydrogen infrastructure. Activities conducted are relevant to a number of propulsion and power systems for terrestrial, aeronautics and aerospace applications. Fuel cell research focused on proton exchange membranes (PEM), solid oxide fuel cells (SOFC). Specific technologies included aircraft fuel cell reformers, new and improved electrodes, electrolytes, interconnect, and seals, modeling of fuel cells including CFD coupled with impedance spectroscopy. Research was conducted on new materials and designs for fuel cells, along with using embedded sensors with power management electronics to improve the power density delivered by fuel cells. Fuel cell applications considered were in-space operations, aviation, and ground-based fuel cells such as; powering auxiliary power units (APUs) in aircraft; high power density, long duration power supplies for interplanetary missions (space science probes and planetary rovers); regenerative capabilities for high altitude aircraft; and power supplies for reusable launch vehicles.

Ab initio nonequilibrium quantum transport and forces with the real-space projector augmented wave method

DEFF Research Database (Denmark)

Chen, Jingzhe; Thygesen, Kristian S.; Jacobsen, Karsten W.

2012-01-01

We present an efficient implementation of a nonequilibrium Green's function method for self-consistent calculations of electron transport and forces in nanostructured materials. The electronic structure is described at the level of density functional theory using the projector augmented wave method...... over k points and real space makes the code highly efficient and applicable to systems containing several hundreds of atoms. The method is applied to a number of different systems, demonstrating the effects of bias and gate voltages, multiterminal setups, nonequilibrium forces, and spin transport....

Effectiveness of Loan Guarantees versus Tax Incentives for Space Launch Ventures

Science.gov (United States)

Scottoline, S.; Coleman, R.

1999-01-01

Over the course of the past few years, several new and innovative fully or partiailly reusable launch vehicle designs have been initiated with the objective of reducing the cost of space transportation. These new designs are in various stages hardware development for technology and system demonstrators. The larger vehicles include the Lockheed Martin X-33 technology demonstrator for VentureStar and the Space Access launcher. The smaller launcher ventures include Kelly Space and Technology and Rotary Rocket Company. A common denominator between the new large and small commercial launch systems is the ability to obtain project financing and at an affordable cost. Both are having or will have great difficulty in obtaining financing in the capital markets because of the dollar amounts and the risk involved. The large established companies are pursuing multi-billion dollar developments which are a major challenge to finance because of the size and risk of the projects. The smaller start-up companies require less capital for their smaller systems, however, their lack of corporate financial muscle and launch vehicle track record results in a major challenge to obtain financing also because of high risk. On Wall Street, new launch system financing is a question of market, technical, organizational, legal/regulatory and financial risk. The current limit of acceptable financial risk for Space businesses on Wall Street are the telecommunications and broadcast satellite projects, of which many in number are projected for the future. Tbc recent problems with Iridium market and financial performance are casting a long shadow over new satellite project financing, making it increasingly difficult for the new satellite projects to obtain needed financing.

Developing Reusable and Reconfigurable Real-Time Software using Aspects and Components

OpenAIRE

Tešanović, Aleksandra

2006-01-01

Our main focus in this thesis is on providing guidelines, methods, and tools for design, configuration, and analysis of configurable and reusable real-time software, developed using a combination of aspect-oriented and component-based software development. Specifically, we define a reconfigurable real-time component model (RTCOM) that describes how a real-time component, supporting aspects and enforcing information hiding, could efficiently be designed and implemented. In this context, we out...

Educational Modelling Language and Learning Design: new challenges for instructional re-usability and personalized learning

NARCIS (Netherlands)

Hummel, Hans; Manderveld, Jocelyn; Tattersall, Colin; Koper, Rob

2003-01-01

Published: Hummel, H. G. K., Manderveld, J. M., Tattersall, C.,& Koper, E. J. R. (2004). Educational Modelling Language: new challenges for instructional re-usability and personalized learning. International Journal of Learning Technology, 1, 1, 110-111.

Space storable propulsion components development

Science.gov (United States)

Hagler, R., Jr.

1982-01-01

The current development status of components to control the flow of propellants (liquid fluorine and hydrazine) in a demonstration space storable propulsion system is discussed. The criteria which determined the designs for the pressure regulator, explosive-actuated valves, propellant shutoff valve, latching solenoid-actuated valve and propellant filter are presented. The test philosophy that was followed during component development is outlined. The results from compatibility demonstrations for reusable connectors, flange seals, and CRES/Ti-6Al4V transition tubes and the evaluations of processes for welding (hand-held TIG, automated TIG, and EB), cleaning for fluorine service, and decontamination after fluorine exposure are described.

Improved method for solving the neutron transport problem by discretization of space and energy variables

International Nuclear Information System (INIS)

Bosevski, T.

1971-01-01

The polynomial interpolation of neutron flux between the chosen space and energy variables enabled transformation of the integral transport equation into a system of linear equations with constant coefficients. Solutions of this system are the needed values of flux for chosen values of space and energy variables. The proposed improved method for solving the neutron transport problem including the mathematical formalism is simple and efficient since the number of needed input data is decreased both in treating the spatial and energy variables. Mathematical method based on this approach gives more stable solutions with significantly decreased probability of numerical errors. Computer code based on the proposed method was used for calculations of one heavy water and one light water reactor cell, and the results were compared to results of other very precise calculations. The proposed method was better concerning convergence rate, decreased computing time and needed computer memory. Discretization of variables enabled direct comparison of theoretical and experimental results

High-Glass-Transition-Temperature Polyimides Developed for Reusable Launch Vehicle Applications

Science.gov (United States)

Chuang, Kathy; Ardent, Cory P.

2002-01-01

Polyimide composites have been traditionally used for high-temperature applications in aircraft engines at temperatures up to 550 F (288 C) for thousands of hours. However, as NASA shifts its focus toward the development of advanced reusable launch vehicles, there is an urgent need for lightweight polymer composites that can sustain 600 to 800 F (315 to 427 C) for short excursions (hundreds of hours). To meet critical vehicle weight targets, it is essential that one use lightweight, high-temperature polymer matrix composites in propulsion components such as turbopump housings, ducts, engine supports, and struts. Composite materials in reusable launch vehicle components will heat quickly during launch and reentry. Conventional composites, consisting of layers of fabric or fiber-reinforced lamina, would either blister or encounter catastrophic delamination under high heating rates above 300 C. This blistering and delamination are the result of a sudden volume expansion within the composite due to the release of absorbed moisture and gases generated by the degradation of the polymer matrix. Researchers at the NASA Glenn Research Center and the Boeing Company (Long Beach, CA) recently demonstrated a successful approach for preventing this delamination--the use of three-dimensional stitched composites fabricated by resin infusion.

High temperature glass thermal control structure and coating. [for application to spacecraft reusable heat shielding

Science.gov (United States)

Stewart, D. A.; Goldstein, H. E.; Leiser, D. B. (Inventor)

1983-01-01

A high temperature stable and solar radiation stable thermal control coating is described which is useful either as such, applied directly to a member to be protected, or applied as a coating on a re-usable surface insulation (RSI). It has a base coat layer and an overlay glass layer. The base coat layer has a high emittance, and the overlay layer is formed from discrete, but sintered together glass particles to give the overlay layer a high scattering coefficient. The resulting two-layer space and thermal control coating has an absorptivity-to-emissivity ratio of less than or equal to 0.4 at room temperature, with an emittance of 0.8 at 1200 F. It is capable of exposure to either solar radiation or temperatures as high as 2000 F without significant degradation. When used as a coating on a silica substrate to give an RSI structure, the coatings of this invention show significantly less reduction in emittance after long term convective heating and less residual strain than prior art coatings for RSI structures.

Self-consistent study of space-charge-dominated beams in a misaligned transport system

International Nuclear Information System (INIS)

Sing Babu, P.; Goswami, A.; Pandit, V.S.

2013-01-01

A self-consistent particle-in-cell (PIC) simulation method is developed to investigate the dynamics of space-charge-dominated beams through a misaligned solenoid based transport system. Evolution of beam centroid, beam envelope and emittance is studied as a function of misalignment parameters for various types of beam distributions. Simulation results performed up to 40 mA of proton beam indicate that centroid oscillations induced by the displacement and rotational misalignments of solenoids do not depend of the beam distribution. It is shown that the beam envelope around the centroid is independent of the centroid motion for small centroid oscillation. In addition, we have estimated the loss of beam during the transport caused by the misalignment for various beam distributions

SSTO RLVs: More Global Reach? A Study of the Use of Single Stage to Orbit Reusable Launch Vehicles as Airlift Platforms.

Science.gov (United States)

1996-11-01

Orbit ( SSTO ) Reusable Launch Vehicles (RLVs) are currently under cooperative development by NASA, the Air Force, and the aerospace industry in the pursuit...exploit these rapid transit technologies to advance ’Global Reach for America.’ The SSTO RLV is a single stage rocket that will be completely reusable...investigated to assess the projected capabilities and costs of the SSTO system. This paper reviews the proposed capabilities of the SSTO system, discusses

What If Annotations Were Reusable: A Preliminary Discussion

Science.gov (United States)

Manouselis, Nikos; Vuorikari, Riina

This paper discusses the rationale for the representation of user feedback in a structured and reusable format so that it can be reused by different recommender systems. We emphasize how information about the context can be included in such a representation. This work-in-progress takes place in the context of two large European initiatives that set up collections of digital educational resources in distributed repositories to serve the needs of different user communities, and to collect user feedback such as ratings, bookmarks and tags related to the resources. The overall aim is to facilitate the exchange and reuse of their data sets in order to support recommendation of appropriate resources to the end users.

Qualitative Simulation of Photon Transport in Free Space Based on Monte Carlo Method and Its Parallel Implementation

Directory of Open Access Journals (Sweden)

Xueli Chen

2010-01-01

Full Text Available During the past decade, Monte Carlo method has obtained wide applications in optical imaging to simulate photon transport process inside tissues. However, this method has not been effectively extended to the simulation of free-space photon transport at present. In this paper, a uniform framework for noncontact optical imaging is proposed based on Monte Carlo method, which consists of the simulation of photon transport both in tissues and in free space. Specifically, the simplification theory of lens system is utilized to model the camera lens equipped in the optical imaging system, and Monte Carlo method is employed to describe the energy transformation from the tissue surface to the CCD camera. Also, the focusing effect of camera lens is considered to establish the relationship of corresponding points between tissue surface and CCD camera. Furthermore, a parallel version of the framework is realized, making the simulation much more convenient and effective. The feasibility of the uniform framework and the effectiveness of the parallel version are demonstrated with a cylindrical phantom based on real experimental results.

A Reusable PZT Transducer for Monitoring Initial Hydration and Structural Health of Concrete

Directory of Open Access Journals (Sweden)

Yaowen Yang

2010-05-01

Full Text Available During the construction of a concrete structure, strength monitoring is important to ensure the safety of both personnel and the structure. Furthermore, to increase the efficiency of in situ casting or precast of concrete, determining the optimal time of demolding is important for concrete suppliers. Surface bonded lead zirconate titanate (PZT transducers have been used for damage detection and parameter identification for various engineering structures over the last two decades. In this work, a reusable PZT transducer setup for monitoring initial hydration of concrete and structural health is developed, where a piece of PZT is bonded to an enclosure with two bolts tightened inside the holes drilled in the enclosure. An impedance analyzer is used to acquire the admittance signatures of the PZT. Root mean square deviation (RMSD is employed to associate the change in concrete strength with changes in the PZT admittance signatures. The results show that the reusable setup is able to effectively monitor the initial hydration of concrete and the structural health. It can also be detached from the concrete for future re-use.

A Reusable PZT Transducer for Monitoring Initial Hydration and Structural Health of Concrete

Science.gov (United States)

Yang, Yaowen; Divsholi, Bahador Sabet; Soh, Chee Kiong

2010-01-01

During the construction of a concrete structure, strength monitoring is important to ensure the safety of both personnel and the structure. Furthermore, to increase the efficiency of in situ casting or precast of concrete, determining the optimal time of demolding is important for concrete suppliers. Surface bonded lead zirconate titanate (PZT) transducers have been used for damage detection and parameter identification for various engineering structures over the last two decades. In this work, a reusable PZT transducer setup for monitoring initial hydration of concrete and structural health is developed, where a piece of PZT is bonded to an enclosure with two bolts tightened inside the holes drilled in the enclosure. An impedance analyzer is used to acquire the admittance signatures of the PZT. Root mean square deviation (RMSD) is employed to associate the change in concrete strength with changes in the PZT admittance signatures. The results show that the reusable setup is able to effectively monitor the initial hydration of concrete and the structural health. It can also be detached from the concrete for future re-use. PMID:22399929

A reusable PZT transducer for monitoring initial hydration and structural health of concrete.

Science.gov (United States)

Yang, Yaowen; Divsholi, Bahador Sabet; Soh, Chee Kiong

2010-01-01

During the construction of a concrete structure, strength monitoring is important to ensure the safety of both personnel and the structure. Furthermore, to increase the efficiency of in situ casting or precast of concrete, determining the optimal time of demolding is important for concrete suppliers. Surface bonded lead zirconate titanate (PZT) transducers have been used for damage detection and parameter identification for various engineering structures over the last two decades. In this work, a reusable PZT transducer setup for monitoring initial hydration of concrete and structural health is developed, where a piece of PZT is bonded to an enclosure with two bolts tightened inside the holes drilled in the enclosure. An impedance analyzer is used to acquire the admittance signatures of the PZT. Root mean square deviation (RMSD) is employed to associate the change in concrete strength with changes in the PZT admittance signatures. The results show that the reusable setup is able to effectively monitor the initial hydration of concrete and the structural health. It can also be detached from the concrete for future re-use.

Architecture and Knowledge-Driven Self-Adaptive Security in Smart Space

Directory of Open Access Journals (Sweden)

Antti Evesti

2013-03-01

Full Text Available Dynamic and heterogeneous smart spaces cause challenges for security because it is impossible to anticipate all the possible changes at design-time. Self-adaptive security is an applicable solution for this challenge. This paper presents an architectural approach for security adaptation in smart spaces. The approach combines an adaptation loop, Information Security Measuring Ontology (ISMO and a smart space security-control model. The adaptation loop includes phases to monitor, analyze, plan and execute changes in the smart space. The ISMO offers input knowledge for the adaptation loop and the security-control model enforces dynamic access control policies. The approach is novel because it defines the whole adaptation loop and knowledge required in each phase of the adaptation. The contributions are validated as a part of the smart space pilot implementation. The approach offers reusable and extensible means to achieve adaptive security in smart spaces and up-to-date access control for devices that appear in the space. Hence, the approach supports the work of smart space application developers.

A user interface development tool for space science systems Transportable Applications Environment (TAE) Plus

Science.gov (United States)

Szczur, Martha R.

1990-01-01

The Transportable Applications Environment Plus (TAE PLUS), developed at NASA's Goddard Space Flight Center, is a portable What You See Is What You Get (WYSIWYG) user interface development and management system. Its primary objective is to provide an integrated software environment that allows interactive prototyping and development that of user interfaces, as well as management of the user interface within the operational domain. Although TAE Plus is applicable to many types of applications, its focus is supporting user interfaces for space applications. This paper discusses what TAE Plus provides and how the implementation has utilized state-of-the-art technologies within graphic workstations, windowing systems and object-oriented programming languages.

Space Charge Compensation in the Linac4 Low Energy Beam Transport Line with Negative Hydrogen Ions

CERN Document Server

Valerio-Lizarraga, C; Leon-Monzon, I; Lettry, J; Midttun, O; Scrivens, R

2014-01-01

The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Tranport (LEBT) using the package IBSimu1, which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H- beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree.

Walkability and walking for transport: characterizing the built environment using space syntax.

Science.gov (United States)

Koohsari, Mohammad Javad; Owen, Neville; Cerin, Ester; Giles-Corti, Billie; Sugiyama, Takemi

2016-11-24

Neighborhood walkability has been shown to be associated with walking behavior. However, the availability of geographical data necessary to construct it remains a limitation. Building on the concept of space syntax, we propose an alternative walkability index, space syntax walkability (SSW). This study examined associations of the full walkability index and SSW with walking for transport (WT). Data were collected in 2003-2004 from 2544 adults living in 154 Census Collection Districts (CCD) in Adelaide, Australia. Participants reported past week WT frequency. Full walkability (consisting of net residential density, intersection density, land use mix, and net retail area ratio) and SSW (consisting of gross population density and a space syntax measure of street integration) were calculated for each CCD using geographic information systems and space syntax software. Generalized linear models with negative binomial variance and logarithmic link functions were employed to examine the associations of each walkability index with WT frequency, adjusting for socio-demographic variables. Two walkability indices were closely correlated (ρ = 0.76, p walkability and SSW with WT frequency were positive, with regression coefficients of 1.12 (95% CI: 1.08, 1.17) and 1.14 (95% CI: 1.10, 1.19), respectively. SSW employs readily-available geographic data, yet is comparable to full walkability in its association with WT. The concept and methods of space syntax provide a novel approach to further understanding how urban design influences walking behaviors.

Compactly packaged monolithic four-wavelength VCSEL array with 100-GHz wavelength spacing for future-proof mobile fronthaul transport.

Science.gov (United States)

Lee, Eun-Gu; Mun, Sil-Gu; Lee, Sang Soo; Lee, Jyung Chan; Lee, Jong Hyun

2015-01-12

We report a cost-effective transmitter optical sub-assembly using a monolithic four-wavelength vertical-cavity surface-emitting laser (VCSEL) array with 100-GHz wavelength spacing for future-proof mobile fronthaul transport using the data rate of common public radio interface option 6. The wavelength spacing is achieved using selectively etched cavity control layers and fine current adjustment. The differences in operating current and output power for maintaining the wavelength spacing of four VCSELs are fiber without any dispersion-compensation techniques.

Spaceborne computer executive routine functional design specification. Volume 1: Functional design of a flight computer executive program for the reusable shuttle

Science.gov (United States)

Curran, R. T.

1971-01-01

A flight computer functional executive design for the reusable shuttle is presented. The design is given in the form of functional flowcharts and prose description. Techniques utilized in the regulation of process flow to accomplish activation, resource allocation, suspension, termination, and error masking based on process primitives are considered. Preliminary estimates of main storage utilization by the Executive are furnished. Conclusions and recommendations for timely, effective software-hardware integration in the reusable shuttle avionics system are proposed.

Shackleton Energy enabling Space Resources Exploitation on the Moon within a Decade

Science.gov (United States)

Keravala, J.; Stone, B.; Tietz, D.; Frischauf, N.

2013-09-01

Access to in-space natural resources is a key requirement for increasing exploration and expansion of humanity off Earth. In particular, making use of the Moon's resources in the form of lunar polar ice to fuel propellant depots at key locations in near Earth space enables dramatic reductions in the cost of access and operations in space, while simultaneously leveraging reusable in-space transporters essential to opening the newspace highway system. Success of this private venture will provide for a sustained balance of our terrestrial economy and the growth of our civilisation. Establishing the cis-Lunar highway required to access lunar sourced water from the cold traps of the polar craters provides the backbone infrastructure for an exponential growth of a space-based economy. With that core infrastructure in place, space-based solar power generation systems, debris mitigation capabilities and planetary protection systems plus scientific and exploratory missions, among others, can become commercial realities in our lifetime. Shackleton Energy was founded from the space, mining, energy and exploration sectors to meet this challenge as a fully private venture. Following successful robotic precursor missions, our industrial astronauts combined with a robotic mining capability will make first landings at the South Pole of the Moon and begin deliveries of propellant to our depots in within a decade. Customers, partners, technologies and most importantly, the investor classes aligned with the risk profiles involved, have been identified and all the components for a viable business are available. Infrastructure investment in space programs has traditionally been the province of governments, but sustainable expansion requires commercial leadership and this is now the responsibility of a dynamic new industry. The technologies and know-how are ready to be applied. Launch services to LEO are available and the industrial capability exists in the aerospace, mining and energy

Approach and landing guidance design for reusable launch vehicle using multiple sliding surfaces technique

Directory of Open Access Journals (Sweden)

Xiangdong LIU

2017-08-01

Full Text Available An autonomous approach and landing (A&L guidance law is presented in this paper for landing an unpowered reusable launch vehicle (RLV at the designated runway touchdown. Considering the full nonlinear point-mass dynamics, a guidance scheme is developed in three-dimensional space. In order to guarantee a successful A&L movement, the multiple sliding surfaces guidance (MSSG technique is applied to derive the closed-loop guidance law, which stems from higher order sliding mode control theory and has advantage in the finite time reaching property. The global stability of the proposed guidance approach is proved by the Lyapunov-based method. The designed guidance law can generate new trajectories on-line without any specific requirement on off-line analysis except for the information on the boundary conditions of the A&L phase and instantaneous states of the RLV. Therefore, the designed guidance law is flexible enough to target different touchdown points on the runway and is capable of dealing with large initial condition errors resulted from the previous flight phase. Finally, simulation results show the effectiveness of the proposed guidance law in different scenarios.

Latest Progress in Research on the SpaceLiner High-Speed Passenger Transportation Concept

OpenAIRE

Sippel, Martin; van Foreest, Arnold

2007-01-01

A vision aimed at revolutionizing ultra-long distance travel between different points on earth could be realized by a high-speed intercontinental passenger transport using rocket based, suborbital launchers. The paper gives an overview on the latest progress in conceptual design of the DLR SpaceLiner presenting geometrical size and mass data and describing results of trajectory simulations. The rockets are based on an advanced but technically conservative approach not relying on e...

A microfluidic control system with re-usable micropump/valve actuator and injection moulded disposable polymer lab-on-a-slide

DEFF Research Database (Denmark)

Bu, Minqiang; Perch-Nielsen, Ivan R.; Yi, Sun

2011-01-01

A microfluidic control system consisting of micropump/valves with a re-usable pneumatic actuator and a disposable polymer lab-on-a-slide is presented. The lab-on-a-slide was fabricated using low cost methods, such as injection moulding of TOPAS® cyclic olefin copolymer (COC) slide, lamination...... of different layers of polymer, and ultrasonic welding of TOPAS® lid to the slide. The re-usable pneumatic actuator not only simplifies the design of the lab-on-a-slide and reduces the fabrication cost, but also reduces the possibility of cross contamination during replacement of the disposable lab...

Support to X-33/Reusable Launch Vehicle Technology Program

Science.gov (United States)

2000-01-01

The Primary activities of Lee & Associates for the referenced Purchase Order has been in direct support of the X-33/Reusable Launch Vehicle Technology Program. An independent review to evaluate the X-33 liquid hydrogen fuel tank failure, which recently occurred after-test of the starboard tank has been provided. The purpose of the Investigation team was to assess the tank design modifications, provide an assessment of the testing approach used by MSFC (Marshall Space Flight Center) in determining the flight worthiness of the tank, assessing the structural integrity, and determining the cause of the failure of the tank. The approach taken to satisfy the objectives has been for Lee & Associates to provide the expertise of Mr. Frank Key and Mr. Wayne Burton who have relevant experience from past programs and a strong background of experience in the fields critical to the success of the program. Mr. Key and Mr. Burton participated in the NASA established Failure Investigation Review Team to review the development and process data and to identify any design, testing or manufacturing weaknesses and potential problem areas. This approach worked well in satisfying the objectives and providing the Review Team with valuable information including the development of a Fault Tree. The detailed inputs were made orally in real time in the Review Team daily meetings. The results of the investigation were presented to the MSFC Center Director by the team on February 15, 2000. Attached are four charts taken from that presentation which includes 1) An executive summary, 2) The most probable cause, 3) Technology assessment, and 4) Technology Recommendations for Cryogenic tanks.

Silica Sulfuric Acid: An Eco-Friendly and Reusable Catalyst for Synthesis of Benzimidazole Derivatives

Directory of Open Access Journals (Sweden)

Bahareh Sadeghi

2013-01-01

Full Text Available Silica sulfuric acid (SiO2-OSO3H as an eco-friendly, readily available, and reusable catalyst is applied to benzimidazole derivatives synthesis under reflux in ethanol. The procedure is very simple and the products are isolated with an easy workup in good-to-excellent yields.

Modern architectures for intelligent systems: reusable ontologies and problem-solving methods.

Science.gov (United States)

Musen, M A

1998-01-01

When interest in intelligent systems for clinical medicine soared in the 1970s, workers in medical informatics became particularly attracted to rule-based systems. Although many successful rule-based applications were constructed, development and maintenance of large rule bases remained quite problematic. In the 1980s, an entire industry dedicated to the marketing of tools for creating rule-based systems rose and fell, as workers in medical informatics began to appreciate deeply why knowledge acquisition and maintenance for such systems are difficult problems. During this time period, investigators began to explore alternative programming abstractions that could be used to develop intelligent systems. The notions of "generic tasks" and of reusable problem-solving methods became extremely influential. By the 1990s, academic centers were experimenting with architectures for intelligent systems based on two classes of reusable components: (1) domain-independent problem-solving methods-standard algorithms for automating stereotypical tasks--and (2) domain ontologies that captured the essential concepts (and relationships among those concepts) in particular application areas. This paper will highlight how intelligent systems for diverse tasks can be efficiently automated using these kinds of building blocks. The creation of domain ontologies and problem-solving methods is the fundamental end product of basic research in medical informatics. Consequently, these concepts need more attention by our scientific community.

A Reusable Component for Communication and Data Synchronization in Mobile Distributed Interactive Applications

Directory of Open Access Journals (Sweden)

Abdul Malik Khan

2010-10-01

Full Text Available In Distributed Interactive Applications (DIA such as multiplayer games, where many participants are involved in a same game session and communicate through a network, they may have an inconsistent view of the virtual world because of the communication delays across the network. This issue becomes even more challenging when communicating through a cellular network while executing the DIA client on a mobile terminal. Consistency maintenance algorithms may be used to obtain a uniform view of the virtual world. These algorithms are very complex and hard to program and therefore, the implementation and the future evolution of the application logic code become difficult. To solve this problem, we propose an approach where the consistency concerns are handled separately by a distributed component called a Synchronization Medium, which is responsible for the communication management as well as the consistency maintenance. We present the detailed architecture of the Synchronization Medium and the generic interfaces it offers to DIAs. We evaluate our approach both qualitatively and quantitatively. We first demonstrate that the Synchronization Medium is a reusable component through the development of two game applications, a car racing game and a space war game. A performance evaluation then shows that the overhead introduced by the Synchronization Medium remains acceptable.

A nu-space for ICS: characterization and application to measure protein transport in live cells.

Science.gov (United States)

Potvin-Trottier, Laurent; Chen, Lingfeng; Horwitz, Alan Rick; Wiseman, Paul W

2013-08-01

We introduce a new generalized theoretical framework for image correlation spectroscopy (ICS). Using this framework, we extend the ICS method in time-frequency ( ν , nu) space to map molecular flow of fluorescently tagged proteins in individual living cells. Even in the presence of a dominant immobile population of fluorescent molecules, nu-space ICS (nICS) provides an unbiased velocity measurement, as well as the diffusion coefficient of the flow, without requiring filtering. We also develop and characterize a tunable frequency-filter for STICS that allows quantification of the density, the diffusion coefficient and the velocity of biased diffusion. We show that the techniques are accurate over a wide range of parameter space in computer simulation. We then characterize the retrograde flow of adhesion proteins ( α 6- and αLβ 2-GFP integrins and mCherry-paxillin) in CHO.B2 cells plated on laminin and ICAM ligands respectively. STICS with a tunable frequency filter, in conjunction with nICS, measures two new transport parameters, the density and transport bias coefficient (a measure of the diffusive character of a flow/biased diffusion), showing that molecular flow in this cell system has a significant diffusive component. Our results suggest that the integrinligand interaction, along with the internal myosin-motor generated force, varies for different integrin-ligand pairs, consistent with previous results.

Scaling laws for oxygen transport across the space-filling system of respiratory membranes in the human lung

Science.gov (United States)

Hou, Chen

Space-filling fractal surfaces play a fundamental role in how organisms function at various levels and in how structure determines function at different levels. In this thesis, we develop a quantitative theory of oxygen transport to and across the surface of the highly branched, space-filling system of alveoli, the fundamental gas exchange unit (acinar airways), in the human lung. Oxygen transport in the acinar airways is by diffusion, and we treat the two steps---diffusion through the branched airways, and transfer across the alveolar membranes---as a stationary diffusion-reaction problem, taking into account that there may be steep concentration gradients between the entrance and remote alveoli (screening). We develop a renormalization treatment of this screening effect and derive an analytic formula for the oxygen current across the cumulative alveolar membrane surface, modeled as a fractal, space-filling surface. The formula predicts the current from a minimum of morphological data of the acinus and appropriate values of the transport parameters, through a number of power laws (scaling laws). We find that the lung at rest operates near the borderline between partial screening and no screening; that it switches to no screening under exercise; and that the computed currents agree with measured values within experimental uncertainties. From an analysis of the computed current as a function of membrane permeability, we find that the space-filling structure of the gas exchanger is simultaneously optimal with respect to five criteria. The exchanger (i) generates a maximum oxygen current at minimum permeability; (ii) 'wastes' a minimum of surface area; (iii) maintains a minimum residence time of oxygen in the acinar airways; (iv) has a maximum fault tolerance to loss of permeability; and (v) generates a maximum current increase when switching from rest to exercise.

A Monte Carlo transport code study of the space radiation environment using FLUKA and ROOT

CERN Document Server

Wilson, T; Carminati, F; Brun, R; Ferrari, A; Sala, P; Empl, A; MacGibbon, J

2001-01-01

We report on the progress of a current study aimed at developing a state-of-the-art Monte-Carlo computer simulation of the space radiation environment using advanced computer software techniques recently available at CERN, the European Laboratory for Particle Physics in Geneva, Switzerland. By taking the next-generation computer software appearing at CERN and adapting it to known problems in the implementation of space exploration strategies, this research is identifying changes necessary to bring these two advanced technologies together. The radiation transport tool being developed is tailored to the problem of taking measured space radiation fluxes impinging on the geometry of any particular spacecraft or planetary habitat and simulating the evolution of that flux through an accurate model of the spacecraft material. The simulation uses the latest known results in low-energy and high-energy physics. The output is a prediction of the detailed nature of the radiation environment experienced in space as well a...

Future orbital transfer vehicle technology study. Volume 2: Technical report

Science.gov (United States)

Davis, E. E.

1982-01-01

Missions for future orbit transfer vehicles (1995-2010) are identified and the technology, operations and vehicle concepts that satisfy the transportation requirements are defined. Comparison of reusable space and ground based LO2/LH2 OTV's was made. Both vehicles used advanced space engines and aero assist capability. The SB OTV provided advantages in life cycle cost, performance and potential for improvement. Comparison of an all LO2/LH2 OTV fleet with a fleet of LO2/LH2 OTVs and electric OTV's was also made. The normal growth technology electric OTV used silicon cells with heavy shielding and argon ion thrusters. This provided a 23% advantage in total transportation cost. The impact of accelerated technology was considered in terms of improvements in performance and cost effectiveness. The accelerated technology electric vehicle used GaAs cells and annealing but did not result in the mixed fleet being any cheaper than an all LO2/LH2 OTV fleet. It is concluded that reusable LO2/LH2 OTV's can serve all general purpose cargo roles between LEO and GEO for the forseeable future. The most significant technology for the second generation vehicle would be space debris protection, on-orbit propellant storage and transfer and on-orbit maintenance capability.

Crew/Automation Interaction in Space Transportation Systems: Lessons Learned from the Glass Cockpit

Science.gov (United States)

Rudisill, Marianne

2000-01-01

The progressive integration of automation technologies in commercial transport aircraft flight decks - the 'glass cockpit' - has had a major, and generally positive, impact on flight crew operations. Flight deck automation has provided significant benefits, such as economic efficiency, increased precision and safety, and enhanced functionality within the crew interface. These enhancements, however, may have been accrued at a price, such as complexity added to crew/automation interaction that has been implicated in a number of aircraft incidents and accidents. This report briefly describes 'glass cockpit' evolution. Some relevant aircraft accidents and incidents are described, followed by a more detailed description of human/automation issues and problems (e.g., crew error, monitoring, modes, command authority, crew coordination, workload, and training). This paper concludes with example principles and guidelines for considering 'glass cockpit' human/automation integration within space transportation systems.

The Ascent Study - Understanding the Market Environment for the Follow-on to the Space Shuttle

Science.gov (United States)

Webber, Derek

2002-01-01

The ASCENT Study - Understanding the Market Environment for the Follow-on to NASA's Marshall Space Flight Center in Huntsville, Alabama, awarded a contract (base plus option amounting to twenty months of analysis) to Futron Corporation in June 2001 to investigate the market environment, and explore the price elasticity attributes, relevant for the introduction of the Second Generation Reusable Launch Vehicle (the follow-on to the Space Shuttle) in the second decade of this century. This work is known as the ASCENT Study (Analysis of Space Concepts Enabled by New Transportation) and data collection covering a total of 42 different sectors took place during 2001. Modeling and forecasting activities for 26 of these markets (all of them international in nature) have been taking place throughout 2002, and the final results of the ASCENT Study, which include 20 year forecasts, are due by the end of January, 2003. This paper describes the markets being analyzed for the ASCENT Study, and includes some preliminary findings in terms of launch vehicle demand during the next 20 years, broken down by mass class and mission type. Amongst these markets are the potential public space travel opportunities. When completed, the final report of the ASCENT Study is expected to represent a significant reference document for all business development, financing and planning activities in the space industry for some time to come. One immediate use will be as a key factor in determining the cargo capability and launch rates to be used for designing the follow-on to the Space Shuttle. The Study will also provide NASA with a quantified indication of the extent to which the lower cost to orbit, made possible by a new class of launch vehicle, will bring into being new markets.

Examining the Use of Web-Based Reusable Learning Objects by Animal and Veterinary Nursing Students

Science.gov (United States)

Chapman-Waterhouse, Emily; Silva-Fletcher, Ayona; Whittlestone, Kim David

2016-01-01

This intervention study examined the interaction of animal and veterinary nursing students with reusable learning objects (RLO) in the context of preparing for summative assessment. Data was collected from 199 undergraduates using quantitative and qualitative methods. Students accessed RLO via personal devices in order to reinforce taught…

Comparison of single-use and reusable metal laryngoscope blades for orotracheal intubation during rapid sequence induction of anesthesia: a multicenter cluster randomized study.

Science.gov (United States)

Amour, Julien; Le Manach, Yannick Le; Borel, Marie; Lenfant, François; Nicolas-Robin, Armelle; Carillion, Aude; Ripart, Jacques; Riou, Bruno; Langeron, Olivier

2010-02-01

Single-use metal laryngoscope blades are cheaper and carry a lower risk of infection than reusable metal blades. The authors compared single-use and reusable metal blades during rapid sequence induction of anesthesia in a multicenter cluster randomized trial. One thousand seventy-two adult patients undergoing general anesthesia under emergency conditions and requiring rapid sequence induction were randomly assigned on a weekly basis to either single-use or reusable metal blades (cluster randomization). After induction, a 60-s period was allowed to complete intubation. In the case of failed intubation, a second attempt was performed using the opposite type of blade. The primary endpoint was the rate of failed intubation, and the secondary endpoints were the incidence of complications (oxygen desaturation, lung aspiration, and/or oropharynx trauma) and the Cormack and Lehane score. Both groups were similar in their main characteristics, including the risk factors for difficult intubation. The rate of failed intubation was significantly decreased with single-use metal blades at the first attempt compared with reusable blades (2.8 vs. 5.4%, P < 0.05). In addition, the proportion of grades III and IV in Cormack and Lehane score were also significantly decreased with single-use metal blades (6 vs. 10%, P < 0.05). The global complication rate did not reach statistical significance, although the same trend was noted (6.8% vs. 11.5%, P = not significant). An investigator survey and a measure of illumination pointed that illumination might have been responsible for this result. The single-use metal blade was more efficient than a reusable metal blade in rapid sequence induction of anesthesia.

Modernization of NASA's Johnson Space Center Chamber: A Payload Transport Rail System to Support Cryogenic Vacuum Optical Testing of the James Webb Space Telescope (JWST)

Science.gov (United States)

Garcia, Sam; Homan, Jonathan; Speed, John

2016-01-01

NASA is the mission lead for the James Webb Space Telescope (JWST), the next of the "Great Observatories", scheduled for launch in 2018. It is directly responsible for the integration and test (I&T) program that will culminate in an end-to-end cryo vacuum optical test of the flight telescope and instrument module in Chamber A at NASA Johnson Space Center. Historic Chamber A is the largest thermal vacuum chamber at Johnson Space Center and one of the largest space simulation chambers in the world. Chamber A has undergone a major modernization effort to support the deep cryogenic, vacuum and cleanliness requirements for testing the JWST. This paper describe the challenges of developing, integrating and modifying new payload rails capable of transporting payloads within the thermal vacuum chamber up to 65,000 pounds. Ambient and Cryogenic Operations required to configure for testing will be explained. Lastly review historical payload configurations stretching from the Apollo program era to current James Webb Space Telescope testing.

Fabrication and Optimization of Stable, Optically Transparent, and Reusable pH-Responsive Silk Membranes

Directory of Open Access Journals (Sweden)

Andreas Toytziaridis

2016-11-01

Full Text Available The fabrication of silk-based membranes that are stable, optically transparent and reusable is yet to be achieved. To address this bottleneck we have developed a method to produce transparent chromogenic silk patches that are optically responsive to pH. The patches were produced by blending regenerated silk fibroin (RSF, Laponite RD (nano clay and the organic dyes neutral red and Thionine acetate. The Laponite RD played a central role in the patch mechanical integrity and prevention of dye leaching. The process was optimized using a factorial design to maximize the patch response to pH by UV absorbance and fluorescence emission. New patches of the optimized protocol, made from solutions containing 125 μM neutral red or 250 μM of Thionine and 15 mg/mL silk, were further tested for operational stability over several cycles of pH altering. Stability, performance, and reusability were achieved over the tested cycles. The approach could be extended to other reporting molecules or enzymes able to bind to Laponite.

Space Transportation Engine Program (STEP), phase B

Science.gov (United States)

1990-01-01

The Space Transportation Engine Program (STEP) Phase 2 effort includes preliminary design and activities plan preparation that will allow smooth and time transition into a Prototype Phase and then into Phases 3, 4, and 5. A Concurrent Engineering approach using Total Quality Management (TQM) techniques, is being applied to define an oxygen-hydrogen engine. The baseline from Phase 1/1' studies was used as a point of departure for trade studies and analyses. Existing STME system models are being enhanced as more detailed module/component characteristics are determined. Preliminary designs for the open expander, closed expander, and gas generator cycles were prepared, and recommendations for cycle selection made at the Design Concept Review (DCR). As a result of July '90 DCR, and information subsequently supplied to the Technical Review Team, a gas generator cycle was selected. Results of the various Advanced Development Programs (ADP's) for the Advanced Launch Systems (ALS) were contributive to this effort. An active vehicle integration effort is supplying the NASA, Air Force, and vehicle contractors with engine parameters and data, and flowing down appropriate vehicle requirements. Engine design and analysis trade studies are being documented in a data base that was developed and is being used to organize information. To date, seventy four trade studies were input to the data base.

Comment on 'Quantum secret sharing based on reusable Greenberger-Horne-Zeilinger states as secure carriers'

International Nuclear Information System (INIS)

Gao Fei; Guo Fenzhuo; Wen Qiaoyan; Zhu Fuchen

2005-01-01

In a recent paper [S. Bagherinezhad and V. Karimipour, Phys. Rev. A 67, 044302 (2003)], a quantum secret sharing protocol based on reusable Greenberger-Horne-Zeilinger states was proposed. However, in this Comment, it is shown that this protocol is insecure if Eve employs a special strategy to attack

Modular and Reusable Power System Design for the BRRISON Balloon Telescope

Science.gov (United States)

Truesdale, Nicholas A.

High altitude balloons are emerging as low-cost alternatives to orbital satellites in the field of telescopic observation. The near-space environment of balloons allows optics to perform near their diffraction limit. In practice, this implies that a telescope similar to the Hubble Space Telescope could be flown for a cost of tens of millions as opposed to billions. While highly feasible, the design of a balloon telescope to rival Hubble is limited by funding. Until a prototype is proven and more support for balloon science is gained, projects remain limited in both hardware costs and man hours. Thus, to effectively create and support balloon payloads, engineering designs must be efficient, modular, and if possible reusable. This thesis focuses specifically on a modular power system design for the BRRISON comet-observing balloon telescope. Time- and cost-saving techniques are developed that can be used for future missions. A modular design process is achieved through the development of individual circuit elements that span a wide range of capabilities. Circuits for power conversion, switching and sensing are designed to be combined in any configuration. These include DC-DC regulators, MOSFET drivers for switching, isolated switches, current sensors and voltage sensing ADCs. Emphasis is also given to commercially available hardware. Pre-fabricated DC-DC converters and an Arduino microcontroller simplify the design process and offer proven, cost-effective performance. The design of the BRRISON power system is developed from these low-level circuits elements. A board for main power distribution supports the majority of flight electronics, and is extensible to additional hardware in future applications. An ATX computer power supply is developed, allowing the use of a commercial ATX motherboard as the flight computer. The addition of new capabilities is explored in the form of a heater control board. Finally, the power system as a whole is described, and its overall

On the use of space photography for identifying transportation routes: A summary of problems

Science.gov (United States)

Simonett, D. S.; Henderson, F. M.; Egbert, D. D.

1970-01-01

It has been widely suggested that space photography may be used for updating maps of transportation networks. Proponents of the argument have suggested that color space photographs of the resolution obtained with Hasselblad 80 mm lenses (about 300 feet) contain enough useful information to update the extensions of major U. S. highways. The present study systematically documents for the Dallas-Fort Worth area the potential of such space photography in detecting, and to a lesser degree identifying, the existing road networks. Color separation plates and an enlargement of the color photograph were produced and all visible roads traced onto transparencies for study. Major roads and roads under construction were the most visible while lower class roads and roads in urban areas had the poorest return. Road width and classification were found to be the major determinant in visibility, varying from 100 per cent visible for divided highways to 15 per cent visible of bladed earth roads. In summary, space photographs of this resolution proved to be difficult to use for accurate road delineation. Only super highways in rural areas with the greatest road-width were completely identifiable, the width being about 1/3 that of the resolution cell.

Data as a service a framework for providing reusable enterprise data services

CERN Document Server

Sarkar, Pushpak

2015-01-01

Data as a Service shows how organizations can leverage "data as a service" by providing real-life case studies on the various and innovative architectures and related patterns. Comprehensive approach to introducing data as a service in any organization. A re-usable and flexible SOA based architecture framework. Roadmap to introduce 'big data as a service' for potential clients. Presents a thorough description of each component in the DaaS reference architecture so readers can implement solutions.

Elective gastropexy with a reusable single-incision laparoscopic surgery port in dogs: 14 cases (2012-2013).

Science.gov (United States)

Stiles, Mandy; Case, J Brad; Coisman, James

2016-08-01

OBJECTIVE To describe the technique, clinical findings, and short-term outcome in dogs undergoing laparoscopic-assisted incisional gastropexy with a reusable single-incision surgery port. DESIGN Retrospective case series. ANIMALS 14 client-owned dogs. PROCEDURES Medical records of dogs referred for elective laparoscopic gastropexy between June 2012 and August 2013 were reviewed. History, signalment, results of physical examination and preoperative laboratory testing, surgical procedure, duration of surgery, postoperative complications, duration of hospital stay, and short-term outcome were recorded. All patients underwent general anesthesia and were positioned in dorsal recumbency. After an initial limited laparoscopic exploration, single-incision laparoscopic-assisted gastropexy was performed extracorporeally in all dogs via a conical port placed in a right paramedian location. Concurrent procedures included laparoscopic ovariectomy (n = 4), gastric biopsy (2), and castration (7). Short-term outcome was evaluated. RESULTS Median duration of surgery was 76 minutes (range, 40 to 90 minutes). Intraoperative complications were minor and consisted of loss of pneumoperitoneum in 2 of 14 dogs. A postoperative surgical site infection occurred in 1 dog and resolved with standard treatment. Median duration of follow-up was 371 days (range, 2 weeks to 1.5 years). No dogs developed gastric dilation-volvulus during the follow-up period, and all owners were satisfied with the outcome. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that single-incision laparoscopic-assisted gastropexy with a reusable conical port was feasible and effective in appropriately selected cases. Investigation of the potential benefits of this reusable port versus single-use devices for elective gastropexy in dogs is warranted.

DRAGON solutions to the 3D transport benchmark over a range in parameter space

International Nuclear Information System (INIS)

Martin, Nicolas; Hebert, Alain; Marleau, Guy

2010-01-01

DRAGON solutions to the 'NEA suite of benchmarks for 3D transport methods and codes over a range in parameter space' are discussed in this paper. A description of the benchmark is first provided, followed by a detailed review of the different computational models used in the lattice code DRAGON. Two numerical methods were selected for generating the required quantities for the 729 configurations of this benchmark. First, S N calculations were performed using fully symmetric angular quadratures and high-order diamond differencing for spatial discretization. To compare S N results with those of another deterministic method, the method of characteristics (MoC) was also considered for this benchmark. Comparisons between reference solutions, S N and MoC results illustrate the advantages and drawbacks of each methods for this 3-D transport problem.

New Approaches in Reusable Booster System Life Cycle Cost Modeling

Science.gov (United States)

Zapata, Edgar

2013-01-01

This paper presents the results of a 2012 life cycle cost (LCC) study of hybrid Reusable Booster Systems (RBS) conducted by NASA Kennedy Space Center (KSC) and the Air Force Research Laboratory (AFRL). The work included the creation of a new cost estimating model and an LCC analysis, building on past work where applicable, but emphasizing the integration of new approaches in life cycle cost estimation. Specifically, the inclusion of industry processes/practices and indirect costs were a new and significant part of the analysis. The focus of LCC estimation has traditionally been from the perspective of technology, design characteristics, and related factors such as reliability. Technology has informed the cost related support to decision makers interested in risk and budget insight. This traditional emphasis on technology occurs even though it is well established that complex aerospace systems costs are mostly about indirect costs, with likely only partial influence in these indirect costs being due to the more visible technology products. Organizational considerations, processes/practices, and indirect costs are traditionally derived ("wrapped") only by relationship to tangible product characteristics. This traditional approach works well as long as it is understood that no significant changes, and by relation no significant improvements, are being pursued in the area of either the government acquisition or industry?s indirect costs. In this sense then, most launch systems cost models ignore most costs. The alternative was implemented in this LCC study, whereby the approach considered technology and process/practices in balance, with as much detail for one as the other. This RBS LCC study has avoided point-designs, for now, instead emphasizing exploring the trade-space of potential technology advances joined with potential process/practice advances. Given the range of decisions, and all their combinations, it was necessary to create a model of the original model

Modelling informally collected quantities of bulky waste and reusable items in Austria.

Science.gov (United States)

Ramusch, R; Pertl, A; Scherhaufer, S; Schmied, E; Obersteiner, G

2015-10-01

Disparities in earnings between Western and Eastern European countries are the reason for a well-established informal sector actively involved in collection and transboundary shipment activities from Austria to Hungary. The preferred objects are reusable items and wastes within the categories bulky waste, WEEE and metals, intended to be sold on flea markets. Despite leading to a loss of recyclable resources for Austrian waste management, these informal activities may contribute to the extension of the lifetime of certain goods when they are reused in Hungary; nevertheless they are discussed rather controversially. The aim of this paper is to provide objective data on the quantities informally collected and transhipped. The unique activities of informal collectors required the development and implementation of a new set of methodologies. The concept of triangulation was used to verify results obtained by field visits, interviews and a traffic counting campaign. Both approaches lead to an estimation of approx. 100,000 t per year of reusable items informally collected in Austria. This means that in addition to the approx. 72 kg/cap/yr formally collected bulky waste, bulky waste wood, household scrap (excluding packaging) and WEEE, up to a further 12 kg/cap/yr might, in the case that informal collection is abandoned, end up as waste or in the second-hand sector. Copyright © 2015 Elsevier Ltd. All rights reserved.

Space Shuttle Program (SSP) Shock Test and Specification Experience for Reusable Flight Hardware Equipment

Science.gov (United States)

Larsen, Curtis E.

2012-01-01

As commercial companies are nearing a preliminary design review level of design maturity, several companies are identifying the process for qualifying their multi-use electrical and mechanical components for various shock environments, including pyrotechnic, mortar firing, and water impact. The experience in quantifying the environments consists primarily of recommendations from Military Standard-1540, Product Verification Requirement for Launch, Upper Stage, and Space Vehicles. Therefore, the NASA Engineering and Safety Center (NESC) formed a team of NASA shock experts to share the NASA experience with qualifying hardware for the Space Shuttle Program (SSP) and other applicable programs and projects. Several team teleconferences were held to discuss past experience and to share ideas of possible methods for qualifying components for multiple missions. This document contains the information compiled from the discussions

The Land Transport Network in the Post-Soviet Space- Problems and Prospective Development

Directory of Open Access Journals (Sweden)

Sergej Schlichter

2012-10-01

Full Text Available Road and rail networks in the post-Soviet space are analysedin view of the demands in transportation to be expected inthe 2 I st centwy. The road system is found te1ribly underdel'elopedin terms of density and canying capacity. It widely fails tofulfil the necessary feeder function for the rail system. Both railand road ~ystems need substantial improvements to allow forthe wgent economic recove1y of that lQige area between thosevital and dynamic regions in east (China, south (Middle Eastund west (Europe.

GoldenBraid: An Iterative Cloning System for Standardized Assembly of Reusable Genetic Modules

Science.gov (United States)

Sarrion-Perdigones, Alejandro; Falconi, Erica Elvira; Zandalinas, Sara I.; Juárez, Paloma; Fernández-del-Carmen, Asun; Granell, Antonio; Orzaez, Diego

2011-01-01

Synthetic Biology requires efficient and versatile DNA assembly systems to facilitate the building of new genetic modules/pathways from basic DNA parts in a standardized way. Here we present GoldenBraid (GB), a standardized assembly system based on type IIS restriction enzymes that allows the indefinite growth of reusable gene modules made of standardized DNA pieces. The GB system consists of a set of four destination plasmids (pDGBs) designed to incorporate multipartite assemblies made of standard DNA parts and to combine them binarily to build increasingly complex multigene constructs. The relative position of type IIS restriction sites inside pDGB vectors introduces a double loop (“braid”) topology in the cloning strategy that allows the indefinite growth of composite parts through the succession of iterative assembling steps, while the overall simplicity of the system is maintained. We propose the use of GoldenBraid as an assembly standard for Plant Synthetic Biology. For this purpose we have GB-adapted a set of binary plasmids for A. tumefaciens-mediated plant transformation. Fast GB-engineering of several multigene T-DNAs, including two alternative modules made of five reusable devices each, and comprising a total of 19 basic parts are also described. PMID:21750718

Optically transparent super-hydrophobic thin film fabricated by reusable polyurethane-acrylate (PUA) mold

Science.gov (United States)

Park, J.-S.; Park, J.-H.; Lee, D.-W.

2018-02-01

In this paper, we describe a simple manufacturing method for producing an optically transparent super-hydrophobic polymer thin film using a reusable photo-curable polymer mold. Soluble photoresist (PR) molds were prepared with under-exposed and under-baked processes, which created unique hierarchical micro/nano structures. The reverse phase of the PR mold was replicated on the surface of polydimethylsiloxane (PDMS) substrates. The unique patterns on the replicated PDMS molds were successfully transferred back to the UV curable polyurethane-acrylate (PUA) using a laboratory-made UV exposure system. Continuous production of the super-hydrophobic PDMS thin film was demonstrated using the reusable PUA mold. In addition, hydrophobic nano-silica powder was sprayed onto the micro/nano structured PDMS surfaces to further improve hydrophobicity. The fabricated PDMS thin films with hierarchical surface texturing showed a water contact angle  ⩾150°. Excellent optical transmittance within the range of visible light of wavelengths between 400-800 nm was experimentally confirmed using a spectrophotometer. High efficiency of the super-hydrophobic PDMS film in optical transparency was also confirmed using solar panels. The fabricated PUA molds are very suitable for use in roll-to-roll or roll-to-plate systems which allow continuous production of super-hydrophobic thin films with an excellent optical transparency.

Casting metal microstructures from a flexible and reusable mold

International Nuclear Information System (INIS)

Cannon, Andrew H; King, William P

2009-01-01

This paper describes casting-based microfabrication of metal microstructures and nanostructures. The metal was cast into flexible silicone molds which were themselves cast from microfabricated silicon templates. Microcasting is demonstrated in two metal alloys of melting temperature 70 °C or 138 °C. Many structures were successfully cast into the metal with excellent replication fidelity, including ridges with periodicity 400 nm and holes or pillars with diameter in the range 10–100 µm and aspect ratio up to 2:1. The flexibility of the silicone mold permits casting of curved surfaces, which we demonstrate by fabricating a cylindrical metal roller of diameter 8 mm covered with microstructures. The metal microstructures can be in turn used as a reusable molding tool

A Reusable Software Architecture for Small Satellite AOCS Systems

DEFF Research Database (Denmark)

Alminde, Lars; Bendtsen, Jan Dimon; Laursen, Karl Kaas

2006-01-01

This paper concerns the software architecture called Sophy, which is an abbreviation for Simulation, Observation, and Planning in HYbrid systems. We present a framework that allows execution of hybrid dynamical systems in an on-line distributed computing environment, which includes interaction...... with both hardware and on-board software. Some of the key issues addressed by the framework are automatic translation of mathematical specifications of hybrid systems into executable software entities, management of execution of coupled models in a parallel distributed environment, as well as interaction...... with external components, hardware and/or software, through generic interfaces. Sophy is primarily intended as a tool for development of model based reusable software for the control and autonomous functions of satellites and/or satellite clusters....

Some Problems of Rocket-Space Vehicles' Characteristics co- ordination

Science.gov (United States)

Sergienko, Alexander A.

2002-01-01

of the XX century suffered a reverse. The designers of the United States' firms and enterprises of aviation and rocket-space industry (Boeing, Rocketdyne, Lockheed Martin, McDonnell Douglas, Rockwell, etc.) and NASA (Marshall Space Flight Center, Johnson Space Center, Langley Research Center and Lewis Research Center and others) could not correctly co-ordinate the characteristics of a propulsion system and a space vehicle for elaboration of the "Single-Stage-To-Orbit" reusable vehicle (SSTO) as an integral whole system, which is would able to inject a payload into an orbit and to return back on the Earth. jet nozzle design as well as the choice of propulsion system characteristics, ensuring the high ballistic efficiency, are considered in the present report. The efficiency criterions for the engine and launch system parameters optimization are discussed. The new methods of the nozzle block optimal parameters' choice for the satisfaction of the object task of flight are suggested. The family of SSTO with a payload mass from 5 to 20 ton and initial weight under 800 ton is considered.

Space Colonization Using Space-Elevators from Phobos

Science.gov (United States)

Weinstein, Leonard M.

2003-01-01

A novel approach is examined for creating an industrial civilization beyond Earth. The approach would take advantage of the unique configuration of Mars and its moon Phobos to make a transportation system capable of raising mass from the surface of Mars to space at a low cost. Mars would be used as the primary location for support personnel and infrastructure. Phobos would be used as a source of raw materials for space-based activity, and as an anchor for tethered carbon-nanotube-based space-elevators. One space-elevator would terminate at the upper edge of Mars' atmosphere. Small craft would be launched from Mars' surface to rendezvous with the moving elevator tip and their payloads detached and raised with solar powered loop elevators to Phobos. Another space-elevator would be extended outward from Phobos to launch craft toward the Earth/Moon system or the asteroid belt. The outward tip would also be used to catch arriving craft. This approach would allow Mars to be colonized, and allow transportation of people and supplies from Mars to support the space industry. In addition, large quantities of material obtained from Phobos could be used to construct space habitats and also supply propellant and material for space industry in the Earth/Moon system as well as around Mars.

Bulk-Like Electrical Properties Induced by Contact-Limited Charge Transport in Organic Diodes: Revised Space Charge Limited Current

KAUST Repository

Xu, Guangwei

2018-02-22

Charge transport governs the operation and performance of organic diodes. Illuminating the charge-transfer/transport processes across the interfaces and the bulk organic semiconductors is at the focus of intensive investigations. Traditionally, the charge transport properties of organic diodes are usually characterized by probing the current–voltage (I–V) curves of the devices. However, to unveil the landscape of the underlying potential/charge distribution, which essentially determines the I–V characteristics, still represents a major challenge. Here, the electrical potential distribution in planar organic diodes is investigated by using the scanning Kelvin probe force microscopy technique, a method that can clearly separate the contact and bulk regimes of charge transport. Interestingly, by applying to devices based on novel, high mobility organic materials, the space-charge-limited-current-like I–V curves, which are previously believed to be a result of the bulk transport, are surprisingly but unambiguously demonstrated to be caused by contact-limited conduction. A model accounting is developed for the transport properties of both the two metal/organic interfaces and the bulk. The results indicate that pure interface-dominated transport can indeed give rise to I–V curves similar to those caused by bulk transport. These findings provide a new insight into the charge injection and transport processes in organic diodes.

A variable-order time-dependent neutron transport method for nuclear reactor kinetics using analytically-integrated space-time characteristics

International Nuclear Information System (INIS)

Hoffman, A. J.; Lee, J. C.

2013-01-01

A new time-dependent neutron transport method based on the method of characteristics (MOC) has been developed. Whereas most spatial kinetics methods treat time dependence through temporal discretization, this new method treats time dependence by defining the characteristics to span space and time. In this implementation regions are defined in space-time where the thickness of the region in time fulfills an analogous role to the time step in discretized methods. The time dependence of the local source is approximated using a truncated Taylor series expansion with high order derivatives approximated using backward differences, permitting the solution of the resulting space-time characteristic equation. To avoid a drastic increase in computational expense and memory requirements due to solving many discrete characteristics in the space-time planes, the temporal variation of the boundary source is similarly approximated. This allows the characteristics in the space-time plane to be represented analytically rather than discretely, resulting in an algorithm comparable in implementation and expense to one that arises from conventional time integration techniques. Furthermore, by defining the boundary flux time derivative in terms of the preceding local source time derivative and boundary flux time derivative, the need to store angularly-dependent data is avoided without approximating the angular dependence of the angular flux time derivative. The accuracy of this method is assessed through implementation in the neutron transport code DeCART. The method is employed with variable-order local source representation to model a TWIGL transient. The results demonstrate that this method is accurate and more efficient than the discretized method. (authors)

A green, reusable SERS film with high sensitivity for in-situ detection of thiram in apple juice

Science.gov (United States)

Sun, Hongbao; Liu, Hai; Wu, Yiyong

2017-09-01

We report a green and reusable surface-enhanced Raman scattering (SERS) film based on PMMA/Ag NPs/graphene. By using this Raman substrate, the SERS signals of R6G were significantly enhanced reaching a minimum detectable concentration of 5 × 10-8 M, due to having lots of hot spots adhered backside to the exposed graphene. The SERS film can be used for in-situ monitoring of trace thiram in apple juice with a detection limit of 1 × 10-6 M (0.24 ppm), which is below the maximal residue limit (MRL) of 7 ppm in fruit prescribed by the U.S. Environmental Protection Agency (EPA). Furthermore, reusability studies show that the SERS film can be used repeatedly. In addition, the graphene-enhanced SERS technique shows great potential applications for the in-situ detection and identification of pesticide residues in environmental water, fruits and vegetables.

Engineering America's Current and Future Space Transportation Systems: 50 Years of Systems Engineering Innovation for Sustainable Exploration

Science.gov (United States)

Dmbacher, Daniel L.; Lyles, Garry M.; McConnaughey, Paul

2008-01-01

Over the past 50 years, the National Aeronautics and Space Administration (NASA) has delivered space transportation solutions for America's complex missions, ranging from scientific payloads that expand knowledge, such as the Hubble Space Telescope, to astronauts and lunar rovers destined for voyages to the Moon. Currently, the venerable Space Shuttle, which has been in service since 1981, provides the United States' (U.S.) capability for both crew and heavy cargo to low-Earth orbit to' construct the International Space Station, before the Shuttle is retired in 2010. In the next decade, NASA will replace this system with a duo of launch vehicles: the Ares I Crew Launch Vehicle and the Ares V Cargo Launch Vehicle (Figure 1). The goals for this new system include increased safety and reliability coupled with lower operations costs that promote sustainable space exploration for decades to come. The Ares I will loft the Orion Crew Exploration Vehicle, while the heavy-lift Ares V will carry the Altair Lunar Lander and the equipment and supplies needed to construct a lunar outpost for a new generation of human and robotic space pioneers. This paper will provide details of the in-house systems engineering and vehicle integration work now being performed for the Ares I and planned for the Ares V. It will give an overview of the Ares I system-level test activities, such as the ground vibration testing that will be conducted in the Marshall Center's Dynamic Test Stand to verify the integrated vehicle stack's structural integrity and to validate computer modeling and simulation (Figure 2), as well as the main propulsion test article analysis to be conducted in the Static Test Stand. These activities also will help prove and refine mission concepts of operation, while supporting the spectrum of design and development work being performed by Marshall's Engineering Directorate, ranging from launch vehicles and lunar rovers to scientific spacecraft and associated experiments

SU-E-T-353: Effects of Time and Temperature On a Potential Reusable 3D Dosimeter

Energy Technology Data Exchange (ETDEWEB)

Juang, T; Miles, D; Crockett, E [Medical Physics Graduate Program, Duke University Medical Center, Durham, NC (United States); Adamovics, J [Rider University, Skillman, NJ (United States); Oldham, M [Duke University Medical Center, Durham, NC (United States)

2015-06-15

Purpose: Preliminary studies of a novel, optically-clearing PRESAGE 3D dosimeter formulation (Presage-RU) demonstrated potential reusability. This study investigates the effects of time and temperature on the accuracy and reusability of Presage-RU, and reports on progress toward developing a reusable 3D dosimeter. Methods: Presage-RU was cast as small volume samples (1×1×4.5cm). The effect of dose response sensitivity with reirradiation and time was evaluated by irradiating samples from 0–10Gy, measuring change in optical density (ΔOD), clearing at room temperature (RT) (5–7 days to fully clear), and then repeating for a total of 5 irradiations. Effects of heating on clearing rate were investigated by irradiating samples to 8Gy, then tracking measurements with samples held at RT, 35°C, and 45°C. Two cylindrical dosimeters (11cm diameter, 9.5cm length) were evaluated for dosimetric accuracy when stored at RT and −3°C prior to irradiation. Plans delivered were 2 overlapping AP fields (RT) and VMAT (-3°C). Results: Heating the dosimeters reduced the clearing half-life from 16.3h at RT to 5.8h (35°C) and 5.1h (45°C), but also increased background ΔOD by 1.7x (35°C) and 2.3x (45°C). Reductions in dose response were more closely linked to age than reirradiation, and storage at RT showed pronounced desensitization from dosimeter edges. These results suggest desensitization from oxygen diffusion. It should be noted that atmospheric diffusion into the dosimeter is not seen in standard, single-use PRESAGE, and is likely caused by differences in the Presage-RU polyurethane matrix. The dosimeter kept in cold storage, however, showed no evidence of desensitization and exhibited accuracy on par with standard PRESAGE with a 3%/3mm 3D gamma passing rate of 98.1%. Conclusions: Presage-RU is sensitive to storage temperatures and time, both of which affect oxygen diffusion and subsequent desensitization. Development shows promising progress with further formulation

Space Elevators: Building a Permanent Bridge for Space Exploration and Economic Development

Science.gov (United States)

Smitherman, David V., Jr.; Howell, Joe T. (Technical Monitor)

2000-01-01

A space elevator is a physical connection from the surface of the Earth to a geo-stationary orbit above the Earth approximately 35,786 km in altitude. Its center of mass is at the geo-stationary point such that it has a 24-hour orbit, and stays over the same point above the equator as the Earth rotates on its axis. The structure is utilized as a transportation and utility system for moving payloads, power, and gases between the surface of the Earth and space. It makes the physical connection from Earth to space in the same way a bridge connects two cities across a body of' water. The space elevator may be an important concept for the future development of space in the latter part of the 21th century. It has the potential to provide mass-transportation to space in the same way highways, railroads, power lines, and pipelines provide mass-transportation across the Earth's surface. The low energy requirements for moving payloads up and down the elevator make it one of only a few concepts that has the potential of lowering the cost to orbit to less than $10 per kilogram. This paper will summarize the findings from a 1999 NASA workshop on Space Elevators held at the NASA Marshall Space Flight Center (MSFC). The workshop was sponsored by the Advanced Projects Office in the Flight Projects Directorate at MSFC, and was organized in cooperation with the Advanced Space Transportation Program at MSFC and the Advanced Concepts Office in the Office of Space Flight at NASA Headquarters. New concepts will be examined for space elevator construction and a number of issues will be discussed that has helped to bring the space elevator concept out of the realm of science fiction and into the realm of possibility. In conclusion, it appears that the space elevator concept may well he possible in the latter part of the 21st century if proper planning and technology development is emphasized to resolve key issues in the development of this advanced space infrastructure concept.

A Technology Plan for Enabling Commercial Space Business

Science.gov (United States)

Lyles, Garry M.

1997-01-01

The National Aeronautics and Space Administration's (NASA) Advanced Space Transportation Program is a customer driven, focused technology program that supports the NASA Strategic Plan and considers future commercial space business projections. The initial cycle of the Advanced Space Transportation Program implementation planning was conducted from December 1995 through February 1996 and represented increased NASA emphasis on broad base technology development with the goal of dramatic reductions in the cost of space transportation. The second planning cycle, conducted in January and February 1997, updated the program implementation plan based on changes in the external environment, increased maturity of advanced concept studies, and current technology assessments. The program has taken a business-like approach to technology development with a balanced portfolio of near, medium, and long-term strategic targets. Strategic targets are influenced by Earth science, space science, and exploration objectives as well as commercial space markets. Commercial space markets include those that would be enhanced by lower cost transportation as well as potential markets resulting in major increases in space business induced by reductions in transportation cost. The program plan addresses earth-to-orbit space launch, earth orbit operations and deep space systems. It also addresses all critical transportation system elements; including structures, thermal protection systems, propulsion, avionics, and operations. As these technologies are matured, integrated technology flight experiments such as the X-33 and X-34 flight demonstrator programs support near-term (one to five years) development or operational decisions. The Advanced Space Transportation Program and the flight demonstrator programs combine business planning, ground-based technology demonstrations and flight demonstrations that will permit industry and NASA to commit to revolutionary new space transportation systems

A nu-space for image correlation spectroscopy: characterization and application to measure protein transport in live cells

Science.gov (United States)

Potvin-Trottier, Laurent; Chen, Lingfeng; Horwitz, Alan Rick; Wiseman, Paul W.

2013-08-01

We introduce a new generalized theoretical framework for image correlation spectroscopy (ICS). Using this framework, we extend the ICS method in time-frequency (ν, nu) space to map molecular flow of fluorescently tagged proteins in individual living cells. Even in the presence of a dominant immobile population of fluorescent molecules, nu-space ICS (nICS) provides an unbiased velocity measurement, as well as the diffusion coefficient of the flow, without requiring filtering. We also develop and characterize a tunable frequency-filter for spatio-temporal ICS (STICS) that allows quantification of the density, the diffusion coefficient and the velocity of biased diffusion. We show that the techniques are accurate over a wide range of parameter space in computer simulation. We then characterize the retrograde flow of adhesion proteins (α6- and αLβ2-GFP integrins and mCherry-paxillin) in CHO.B2 cells plated on laminin and intercellular adhesion molecule 1 (ICAM-1) ligands respectively. STICS with a tunable frequency filter, in conjunction with nICS, measures two new transport parameters, the density and transport bias coefficient (a measure of the diffusive character of a flow/biased diffusion), showing that molecular flow in this cell system has a significant diffusive component. Our results suggest that the integrin-ligand interaction, along with the internal myosin-motor generated force, varies for different integrin-ligand pairs, consistent with previous results.

14 CFR 206.1 - Emergency transportation.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Emergency transportation. 206.1 Section 206.1 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS... EXEMPTIONS § 206.1 Emergency transportation. Notwithstanding the provisions of section 41101 of the Statute...

Design study of RL10 derivatives. Volume 3, part 2: Operational and flight support plan. [analysis of transportation requirements for rocket engine in support of space tug program

Science.gov (United States)

Shubert, W. C.

1973-01-01

Transportation requirements are considered during the engine design layout reviews and maintenance engineering analyses. Where designs cannot be influenced to avoid transportation problems, the transportation representative is advised of the problems permitting remedies early in the program. The transportation representative will monitor and be involved in the shipment of development engine and GSE hardware between FRDC and vehicle manufacturing plant and thereby will be provided an early evaluation of the transportation plans, methods and procedures to be used in the space tug support program. Unanticipated problems discovered in the shipment of development hardware will be known early enough to permit changes in packaging designs and transportation plans before the start of production hardware and engine shipments. All conventional transport media can be used for the movement of space tug engines. However, truck transport is recommended for ready availability, variety of routes, short transit time, and low cost.

A development of logistics management models for the Space Transportation System

Science.gov (United States)

Carrillo, M. J.; Jacobsen, S. E.; Abell, J. B.; Lippiatt, T. F.

1983-01-01

A new analytic queueing approach was described which relates stockage levels, repair level decisions, and the project network schedule of prelaunch operations directly to the probability distribution of the space transportation system launch delay. Finite source population and limited repair capability were additional factors included in this logistics management model developed specifically for STS maintenance requirements. Data presently available to support logistics decisions were based on a comparability study of heavy aircraft components. A two-phase program is recommended by which NASA would implement an integrated data collection system, assemble logistics data from previous STS flights, revise extant logistics planning and resource requirement parameters using Bayes-Lin techniques, and adjust for uncertainty surrounding logistics systems performance parameters. The implementation of these recommendations can be expected to deliver more cost-effective logistics support.

Scalable and reusable emulator for evaluating the performance of SS7 networks

Science.gov (United States)

Lazar, Aurel A.; Tseng, Kent H.; Lim, Koon Seng; Choe, Winston

1994-04-01

A scalable and reusable emulator was designed and implemented for studying the behavior of SS7 networks. The emulator design was largely based on public domain software. It was developed on top of an environment supported by PVM, the Parallel Virtual Machine, and managed by OSIMIS-the OSI Management Information Service platform. The emulator runs on top of a commercially available ATM LAN interconnecting engineering workstations. As a case study for evaluating the emulator, the behavior of the Singapore National SS7 Network under fault and unbalanced loading conditions was investigated.

Performance of a neutron transport code with full phase space decomposition on the Cray Research T3D

International Nuclear Information System (INIS)

Dorr, M.R.; Salo, E.M.

1995-01-01

We present performance results obtained on a 128-node Cray Research T3D computer by a neutron transport code implementing a standard mtiltigroup, discrete ordinates algorithm on a three-dimensional Cartesian grid. After summarizing the implementation strategy used to obtain a full decomposition of phase space (i.e., simultaneous parallelization of the neutron energy, directional and spatial variables), we investigate the scalability of the fundamental source iteration step with respect to each phase space variable. We also describe enhancements that have enabled performance rates approaching 10 gigaflops on the full 128-node machine

Best practices in road transport: An exploratory study

Directory of Open Access Journals (Sweden)

Mar Fernández Vázquez-Noguerol

2018-04-01

Full Text Available Purpose: Road transport aspects are becoming increasingly important due to their high impact on economic, environmental and social sustainability. Considering the triple bottom line approach, best practices play a fundamental role within organisations. The purpose of this paper is to analyse several sustainable initiatives in road transport adopted by companies. Design/methodology/approach: The findings were developed and evaluated based on empirical data captured through a survey of 98 professionals involved in logistics and transport activities. Additionally, key literature on transport initiatives was reviewed to supplement the framework for the implementation of best practices in road transport. Findings: The exploratory study shows the importance of each best practice and determines the level of implementation of each initiative, comparing the results among different dealers (retailers, wholesalers, carriers and manufacturers, type of transport fleet and companies’ revenues. Research limitations/implications: The sample of 98 companies was based on simple search filters and the group is not wholly representative of all sectors. Respondents were mainly managers from Spain involved in logistics and transport activities. Surveyed companies included manufacturing, retailers, wholesalers and third-party logistics providers. Practical implications: The most common best practices in road transport are identified, including initiatives related to: efficiency, reusability, safety, optimization, emissions, waste and recycling. Initiatives that influence road transport are ranked by their degree of implementation in the companies analysed.  Social implications: Implementation of some of these best practices may help lessen negative impacts of road transport on society and the environment. Originality/value: The study results indicate which practices are most frequently used and their level of implementation depending on companies’ roles in the

Probability Distribution for Flowing Interval Spacing

International Nuclear Information System (INIS)

Kuzio, S.

2001-01-01

The purpose of this analysis is to develop a probability distribution for flowing interval spacing. A flowing interval is defined as a fractured zone that transmits flow in the Saturated Zone (SZ), as identified through borehole flow meter surveys (Figure 1). This analysis uses the term ''flowing interval spacing'' as opposed to fractured spacing, which is typically used in the literature. The term fracture spacing was not used in this analysis because the data used identify a zone (or a flowing interval) that contains fluid-conducting fractures but does not distinguish how many or which fractures comprise the flowing interval. The flowing interval spacing is measured between the midpoints of each flowing interval. Fracture spacing within the SZ is defined as the spacing between fractures, with no regard to which fractures are carrying flow. The Development Plan associated with this analysis is entitled, ''Probability Distribution for Flowing Interval Spacing'', (CRWMS M and O 2000a). The parameter from this analysis may be used in the TSPA SR/LA Saturated Zone Flow and Transport Work Direction and Planning Documents: (1) ''Abstraction of Matrix Diffusion for SZ Flow and Transport Analyses'' (CRWMS M and O 1999a) and (2) ''Incorporation of Heterogeneity in SZ Flow and Transport Analyses'', (CRWMS M and O 1999b). A limitation of this analysis is that the probability distribution of flowing interval spacing may underestimate the effect of incorporating matrix diffusion processes in the SZ transport model because of the possible overestimation of the flowing interval spacing. Larger flowing interval spacing results in a decrease in the matrix diffusion processes. This analysis may overestimate the flowing interval spacing because the number of fractures that contribute to a flowing interval cannot be determined from the data. Because each flowing interval probably has more than one fracture contributing to a flowing interval, the true flowing interval spacing could be

Standards and Specifications for Ground Processing of Space Vehicles: From an Aviation-Based Shuttle Project to Global Application

Science.gov (United States)

Ingalls, John; Cipolletti, John

2011-01-01

Proprietary or unique designs and operations are expected early in any industry's development, and often provide a competitive early market advantage. However, there comes a time when a product or industry requires standardization for the whole industry to advance...or survive. For the space industry, that time has come. Here, we will focus on standardization of ground processing for space vehicles and their ground systems. With the retirement of the Space Shuttle, and emergence of a new global space race, affordability and sustainability are more important now than ever. The growing commercialization of the space industry and current global economic environment are driving greater need for efficiencies to save time and money. More RLV's (Reusable Launch Vehicles) are being developed for the gains of reusability not achievable with traditional ELV's (Expendable Launch Vehicles). More crew/passenger vehicles are also being developed. All of this calls for more attention needed for ground processing-repeatedly before launch and after landing/recovery. RLV's should provide more efficiencies than ELV's, as long as MRO (Maintenance, Repair, and Overhaul) is well-planned-even for the unplanned problems. NASA's Space Shuttle is a primary example of an RLV which was supposed to thrive on reusability savings with efficient ground operations, but lessons learned show that costs were (and still are) much greater than expected. International standards and specifications can provide the commonality needed to simplify design and manufacturing as well as to improve safety, quality, maintenance, and operability. There are standards organizations engaged in the space industry, but ground processing is one of the areas least addressed. Challenges are encountered due to various factors often not considered during development. Multiple vehicle elements, sites, customers, and contractors pose various functional and integration difficulties. Resulting technical publication structures

14 CFR 375.35 - Free transportation.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Free transportation. 375.35 Section 375.35 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) SPECIAL... transportation. (a) Foreign civil aircraft may be navigated in the United States by a foreign air carrier for the...

Crew Transportation Technical Management Processes

Science.gov (United States)

Mckinnie, John M. (Compiler); Lueders, Kathryn L. (Compiler)

2013-01-01

Under the guidance of processes provided by Crew Transportation Plan (CCT-PLN-1100), this document, with its sister documents, International Space Station (ISS) Crew Transportation and Services Requirements Document (CCT-REQ-1130), Crew Transportation Technical Standards and Design Evaluation Criteria (CCT-STD-1140), Crew Transportation Operations Standards (CCT STD-1150), and ISS to Commercial Orbital Transportation Services Interface Requirements Document (SSP 50808), provides the basis for a National Aeronautics and Space Administration (NASA) certification for services to the ISS for the Commercial Provider. When NASA Crew Transportation System (CTS) certification is achieved for ISS transportation, the Commercial Provider will be eligible to provide services to and from the ISS during the services phase.

Note: reliable and reusable ultrahigh vacuum optical viewports.

Science.gov (United States)

Arora, P; Sen Gupta, A

2012-04-01

We report a simple technique for the realization of ultrahigh vacuum optical viewports. The technique relies on using specially designed thin copper knife-edges and using a thin layer of Vacseal(®) on tip of the knife-edges between the optical flat and the ConFlat(®) (CF) flange. The design of the windows is such that it gives uniform pressure on the flat without breaking it. The assembled window is a complete unit, which can be mounted directly onto a CF flange of the vacuum chamber. It can be removed and reused without breaking the window seal. The design is reliable as more than a dozen such windows have survived several bake out and cooling cycles and have been leak tested up to 10(-11) Torr l/s level with a commercial Helium leak detector. The advantages of this technique are ease of assembly and leak proof sealing that survives multiple temperature cycling making the windows reliable and reusable. © 2012 American Institute of Physics

Reusable Solid Rocket Motor - V(RSRMV)Nozzle Forward Nose Ring Thermo-Structural Modeling

Science.gov (United States)

Clayton, J. Louie

2012-01-01

During the developmental static fire program for NASAs Reusable Solid Rocket Motor-V (RSRMV), an anomalous erosion condition appeared on the nozzle Carbon Cloth Phenolic nose ring that had not been observed in the space shuttle RSRM program. There were regions of augmented erosion located on the bottom of the forward nose ring (FNR) that measured nine tenths of an inch deeper than the surrounding material. Estimates of heating conditions for the RSRMV nozzle based on limited char and erosion data indicate that the total heat loading into the FNR, for the new five segment motor, is about 40-50% higher than the baseline shuttle RSRM nozzle FNR. Fault tree analysis of the augmented erosion condition has lead to a focus on a thermomechanical response of the material that is outside the existing experience base of shuttle CCP materials for this application. This paper provides a sensitivity study of the CCP material thermo-structural response subject to the design constraints and heating conditions unique to the RSRMV Forward Nose Ring application. Modeling techniques are based on 1-D thermal and porous media calculations where in-depth interlaminar loading conditions are calculated and compared to known capabilities at elevated temperatures. Parameters such as heat rate, in-depth pressures and temperature, degree of char, associated with initiation of the mechanical removal process are quantified and compared to a baseline thermo-chemical material removal mode. Conclusions regarding postulated material loss mechanisms are offered.

In-Space Propellant Production Using Water

Science.gov (United States)

Notardonato, William; Johnson, Wesley; Swanger, Adam; McQuade, William

2012-01-01

A new era of space exploration is being planned. Manned exploration architectures under consideration require the long term storage of cryogenic propellants in space, and larger science mission directorate payloads can be delivered using cryogenic propulsion stages. Several architecture studies have shown that in-space cryogenic propulsion depots offer benefits including lower launch costs, smaller launch vehicles, and enhanced mission flexibility. NASA is currently planning a Cryogenic Propellant Storage and Transfer (CPST) technology demonstration mission that will use existing technology to demonstrate long duration storage, acquisition, mass gauging, and transfer of liquid hydrogen in low Earth orbit. This mission will demonstrate key technologies, but the CPST architecture is not designed for optimal mission operations for a true propellant depot. This paper will consider cryogenic propellant depots that are designed for operability. The operability principles considered are reusability, commonality, designing for the unique environment of space, and use of active control systems, both thermal and fluid. After considering these operability principles, a proposed depot architecture will be presented that uses water launch and on orbit electrolysis and liquefaction. This could serve as the first true space factory. Critical technologies needed for this depot architecture, including on orbit electrolysis, zero-g liquefaction and storage, rendezvous and docking, and propellant transfer, will be discussed and a developmental path forward will be presented. Finally, use of the depot to support the NASA Science Mission Directorate exploration goals will be presented.

Chamber transport

International Nuclear Information System (INIS)

Olson, Craig L.

2001-01-01

Heavy ion beam transport through the containment chamber plays a crucial role in all heavy ion fusion (HIF) scenarios. Here, several parameters are used to characterize the operating space for HIF beams; transport modes are assessed in relation to evolving target/accelerator requirements; results of recent relevant experiments and simulations of HIF transport are summarized; and relevant instabilities are reviewed. All transport options still exist, including (1) vacuum ballistic transport, (2) neutralized ballistic transport, and (3) channel-like transport. Presently, the European HIF program favors vacuum ballistic transport, while the US HIF program favors neutralized ballistic transport with channel-like transport as an alternate approach. Further transport research is needed to clearly guide selection of the most attractive, integrated HIF system

Chemical transport reactions

CERN Document Server

Schäfer, Harald

2013-01-01

Chemical Transport Reactions focuses on the processes and reactions involved in the transport of solid or liquid substances to form vapor phase reaction products. The publication first offers information on experimental and theoretical principles and the transport of solid substances and its special applications. Discussions focus on calculation of the transport effect of heterogeneous equilibria for a gas motion between equilibrium spaces; transport effect and the thermodynamic quantities of the transport reaction; separation and purification of substances by means of material transport; and

Planning, Implementation and Optimization of Future space Missions using an Immersive Visualization Environement (IVE) Machine

Science.gov (United States)

Harris, E.

Planning, Implementation and Optimization of Future Space Missions using an Immersive Visualization Environment (IVE) Machine E. N. Harris, Lockheed Martin Space Systems, Denver, CO and George.W. Morgenthaler, U. of Colorado at Boulder History: A team of 3-D engineering visualization experts at the Lockheed Martin Space Systems Company have developed innovative virtual prototyping simulation solutions for ground processing and real-time visualization of design and planning of aerospace missions over the past 6 years. At the University of Colorado, a team of 3-D visualization experts are developing the science of 3-D visualization and immersive visualization at the newly founded BP Center for Visualization, which began operations in October, 2001. (See IAF/IAA-01-13.2.09, "The Use of 3-D Immersive Visualization Environments (IVEs) to Plan Space Missions," G. A. Dorn and G. W. Morgenthaler.) Progressing from Today's 3-D Engineering Simulations to Tomorrow's 3-D IVE Mission Planning, Simulation and Optimization Techniques: 3-D (IVEs) and visualization simulation tools can be combined for efficient planning and design engineering of future aerospace exploration and commercial missions. This technology is currently being developed and will be demonstrated by Lockheed Martin in the (IVE) at the BP Center using virtual simulation for clearance checks, collision detection, ergonomics and reach-ability analyses to develop fabrication and processing flows for spacecraft and launch vehicle ground support operations and to optimize mission architecture and vehicle design subject to realistic constraints. Demonstrations: Immediate aerospace applications to be demonstrated include developing streamlined processing flows for Reusable Space Transportation Systems and Atlas Launch Vehicle operations and Mars Polar Lander visual work instructions. Long-range goals include future international human and robotic space exploration missions such as the development of a Mars

Reusable rocket engine preventive maintenance scheduling using genetic algorithm

International Nuclear Information System (INIS)

Chen, Tao; Li, Jiawen; Jin, Ping; Cai, Guobiao

2013-01-01

This paper deals with the preventive maintenance (PM) scheduling problem of reusable rocket engine (RRE), which is different from the ordinary repairable systems, by genetic algorithm. Three types of PM activities for RRE are considered and modeled by introducing the concept of effective age. The impacts of PM on all subsystems' aging processes are evaluated based on improvement factor model. Then the reliability of engine is formulated by considering the accumulated time effect. After that, optimization model subjected to reliability constraint is developed for RRE PM scheduling at fixed interval. The optimal PM combination is obtained by minimizing the total cost in the whole life cycle for a supposed engine. Numerical investigations indicate that the subsystem's intrinsic reliability characteristic and the improvement factor of maintain operations are the most important parameters in RRE's PM scheduling management

Underground spaces/cybernetic spaces

Directory of Open Access Journals (Sweden)

Tomaž Novljan

2000-01-01

Full Text Available A modern city space is a space where in the vertical and horizontal direction dynamic, non-linear processes exist, similar as in nature. Alongside the “common” city surface, cities have underground spaces as well that are increasingly affecting the functioning of the former. It is the space of material and cybernetic communication/transport. The psychophysical specifics of using underground places have an important role in their conceptualisation. The most evident facts being their limited volume and often limited connections to the surface and increased level of potential dangers of all kinds. An efficient mode for alleviating the effects of these specific features are artistic interventions, such as: shape, colour, lighting, all applications of the basic principles of fractal theory.