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1

Budgetary Implications of NASA's Current Plans for Space Exploration.  

National Technical Information Service (NTIS)

In 2004, President Bush announced his Vision for U.S. Space Exploration, which called for the National Aeronautics and Space Administration (NASA) to develop new vehicles for spaceflight that would allow humans to return to the moon by 2020. In response, ...

2009-01-01

2

The space elevator in the context of current space exploration policy  

Microsoft Academic Search

The space elevator is an advanced space transportation system that someday could replace chemical rockets as humanity's primary means of reaching Earth's orbit. However, before this can occur, a number of enabling technologies will need to be developed, and a variety of economic and policy questions must be addressed. The goal of this paper is to examine the feasibility of

Mark S. Avnet

2006-01-01

3

Biomimetics Applied to Space Exploration  

Microsoft Academic Search

Abstract A review of the possible applications of biomimetic research and engineering to space exploration ,is presented. The review ,begins ,by briefly ,introducing biomimicry as an engineering discipline, and then, through considering the characteristics that typify current and future space exploration missions, along with the characteristics commonly associated with biological systems, it is argued that biomimicry,has a high ,degree of

Mark Ayre

4

Nutrition for Space Exploration.  

National Technical Information Service (NTIS)

Nutrition has proven to be critical throughout the history of human exploration, on both land and water. The importance of nutrition during long-duration space exploration is no different. Maintaining optimal nutritional status is critical for all bodily ...

S. M. Smith

2005-01-01

5

Exploring the energy/beam current parameter space for the isotope production facility (IPF) at LANSCE  

SciTech Connect

IPF has recently investigated isotope production with proton beams at energies other than the 100-MeV currently available to the IPF beam line. To maximize the yield of a particular isotope, it is necessary to measure the production rate and cross section versus proton beam energy. Studies were conducted at 800 MeV and 197 MeV to determine the cross section of Tb-159. Also, the ability to irradiate targets at different proton beam energies opens up the possibility of producing other radioisotopes. A proof-of-principle test was conducted to develop a 40-MeV tune in the 100-MeV beam line. Another parameter explored was the beam current, which was raised from the normal limit of 250 {mu}A up to 356 {mu}A via both power and repetition rate increase. This proof-of-principle test demonstrated the capability of the IPF beam line for high current operation with potential for higher isotope yields. For the full production mode, system upgrades will need to be in place to operate at high current and high duty factor. These activities are expected to provide the data needed for the development of a new and unique isotope production capability complementing the existing 100-MeV IPF facility.

Gulley, Mark S [Los Alamos National Laboratory; Bach, Hong [Los Alamos National Laboratory; Nortier, Francis M [Los Alamos National Laboratory; Pillai, Chandra [Los Alamos National Laboratory; Bitteker, Leo J [Los Alamos National Laboratory; John, Kevin D [Los Alamos National Laboratory; Valdez, Frank O [Los Alamos National Laboratory; Seifter, Achim [Los Alamos National Laboratory

2010-09-07

6

History of Space Exploration  

NSDL National Science Digital Library

Users can choose from an extensive selection of links to resources for use in the study of the history of space exploration. The links provide access to historic information and publications, chronologies, and mission summaries for American, Russian, European, and other space missions. For educators, there are links to guides to robotic spacecraft and to observing the space shuttle in orbit. Links are also provided to a variety of spacecraft homepages and to other topics such as a primer on the basics of space flight, the Apollo lunar surface journals, and the NASA historic archives.

7

Robotics for space exploration  

NASA Astrophysics Data System (ADS)

The robotic potential for the Space Exploration Initiative and the First Lunar Outpost, as well as some of the challenges that appear to be presented are reviewed. Parallels are drawn to other bodies of system engineering where system engineering methodologies are well developed. Comparsions between metrics and robotic system engineering are also presented.

Seidman, Lawrence P.; Huber, Eric L.

1992-11-01

8

Space Science in Action: Space Exploration [Videotape].  

ERIC Educational Resources Information Center

|In this videotape recording, students learn about the human quest to discover what is out in space. Students see the challenges and benefits of space exploration including the development of rocket science, a look back at the space race, and a history of manned space travel. A special section on the Saturn V rocket gives students insight into the…

1999

9

Robotic Exploration of Space Timeline  

NSDL National Science Digital Library

This interactive timeline from NASA journeys through the last century, detailing key discoveries, experiments, missions, and other events that brought robotic space exploration from science fiction to reality.

Foundation, Wgbh E.

2005-12-17

10

The Space Science Explorers Series  

NSDL National Science Digital Library

The National Aeronautics and Space Administration (NASA) Space Explorers Series is a collection of articles on 'Space Explorers', people connected by their interest in space science and research. This monthly series will introduce the reader to these people, young and old, and with a variety of backgrounds and interests. The articles are designed for a wide range of educational levels and feature career profiles and biographical information on the Space Explorers. The Institute for Global Environmental Strategies (IGES) maintains a topic index for users who want to browse archived articles by subject.

11

Exploring Earth from Space  

NSDL National Science Digital Library

This set of lithographs from the ISS EarthKAM program contains an educators' guide, student information and worksheets, and several Earth photos taken from the Space Shuttle. Shuttle astronauts and the ISS EarthKAM program provide photos of our planet from the unique perspective of Earth orbit. This resource can enhance students' studies of Earth and space science, geography, social studies, mathematics, and educational technologies.

2002-12-01

12

Radioelectronics and space exploration  

NASA Astrophysics Data System (ADS)

Citing the 23 years since Yuriy Gagarin's first radio transmission from outer space, the developments in radio communications and their role in mission control are summarized. Use of satellites for radio and television links with ground stations are an important part of information exchange. Construction and preventive maintenance activities by Soviet cosmonauts, use of radio technology for docking procedures and the reliability of such equipment, and the growing role of computer technology in space vehicles with human crews and pilotless craft are discussed. Automatic interplanetary vehicles that have landed on the moon, Mars and Venus, as well as artificial earth satellites, are facilitating weather and communication advances. Mock space equipment using radio and computer technology is of great importance for training cosmonauts. Despite all these practical applications, optimum utilization of automated equipment has yet to be achieved, and offers further challenge to Soviet and other engineers and technicians.

Sarafanov, T.; Bogoroditskiy, Y.; Milyukov, I.

1985-03-01

13

Radioelectronics and space exploration  

Microsoft Academic Search

Citing the 23 years since Yuriy Gagarin's first radio transmission from outer space, the developments in radio communications and their role in mission control are summarized. Use of satellites for radio and television links with ground stations are an important part of information exchange. Construction and preventive maintenance activities by Soviet cosmonauts, use of radio technology for docking procedures and

T. Sarafanov; Y. Bogoroditskiy; I. Milyukov

1985-01-01

14

Space exploration in neglect  

Microsoft Academic Search

Summary The present study investigated the gaze as well as the head and the eye-in-head movements of neglect patients while they were exploring their surroundings. A random configuration of letters was presented on the inner surface of a sphere that surrounded the subject, requiring free exploratory eye and head movements. The subjects were requested to search for a single (non-existent)

H.-O. Karnath; M. Niemeier; J. Dichgans

1998-01-01

15

From space exploration to commercialisation  

Microsoft Academic Search

Space exploration has captured the imagination and dreams of many scientists, engineers and visionaries.The ISS is being built by five ISS partners; NASA, RSA, ESA, CSA and JAXA. ISS commercialisation is the process by which ISS products and services are sold to private companies, without transferring ISS ownership. This thesis has two objectives; to propose a collaboration between space agencies

S. A. Tkatchova

2006-01-01

16

SCIENTIFIC INSTRUMENTS IN SPACE EXPLORATION  

Microsoft Academic Search

The path is a long one between the conception of a scientific instrument ; for space exploration and the goal of obtaining scientific measurements from ; space, from the moon, or from the atmosphere or the surface of a planet. These ; instruments must be designed to meet the scientific objectives under adverse ; environmental conditions and within the constraints

R. L. Heacock

1963-01-01

17

Why Do We Explore Space?  

NASA Astrophysics Data System (ADS)

The launch of the Soviet Sputnik satellite in 1957 challenged the American space enterprise to a race for political and technological superiority. During the Cold War era, the space program had a very clear goal - to show the world that we were the premier force and player in this new frontier. The American public could, therefore, relate to such a simplistic goal and largely was very supportive of the US space program. Since the end of the Cold War, the raison d'etre for space exploration has been less clear and not as well articulated. This paper is part of a dialogue hoping to solicit input from the public domain on the topic of space exploration. We first examine a previous study on some of the "why's" anticipated by the American public. Then we propose a triumvirate perspective to seek a balance among the romantic, pragmatic and scientific aspects of space faring ventures. Finally, we suggest a somewhat simplistic message that can be more easily related to the common person on the street. We assert that we go to space to "explore the Heavens, enhance the Earth and enrich humankind", and cite numerous concrete examples to support these three themes.(Disclaimer: these are personal ideas and opinions of the authors and do not represent an official NASA position. All references to NASA information are from NASA web pages or in the public domain. This paper is written from an American vantage point due to the authors' experience with the American space agency.)

Ng, E. W.; Skiles, J. W.

2006-09-01

18

Ethics and the Space Explorer  

NASA Astrophysics Data System (ADS)

Ethics is not a word often encountered at meetings of space activists or in work groups planning a space future. Yet, the planning of space exploration ought to have ethical dimensions because space workers are not disconnected from the remainder of society in either their professional disciplines, in their institutions, or in the subject matter they choose to study. As a scientist, I have been trained in the schema of research. Although the scientific method is noted for its system of self -correction in the form of peer review, sharing of information, and repeatability of new findings, the enterprise of universal knowledge still depends heavily on an ethical system rooted in honesty in the reporting of findings and in the processing of data. As a government employee, I receive annual "ethical training". However, the training consists almost entirely of reminders to obey various laws governing the activities and the external relationships of government employees. For 20 years l have been involved in discussions of possible futures for human exploration of space beyond low Earth orbit. Many scenarios ranging from lunar landing to Martian settlement have been discussed without any mention of possible ethical issues. l remember hearing Apollo astronaut Harrison Schmitt once remark that space exploration was attractive because technology can be employed in its purest form in the conquest of space. His point was that the challenge was Man against Nature, a struggle in which the consequences or side effects of technology was not an issue. To paraphrase, in space you do not need an environmental impact study. I wish to analyze this proposition with regard to contexts in which people initiate, or plan to initiate, activities in space. Depending on the situation, space can be viewed as a laboratory, as a frontier, as a resource, as an environment, or as a location to conduct business. All of these associations and contexts also are found in our everyday activities on Earth, and by analogy ethical issues exist that translate into the spatial dimension.

Mendell, W.

2002-01-01

19

"Space, the Final Frontier"; Books on Space and Space Exploration.  

ERIC Educational Resources Information Center

Advocates play in a child's life. Describes how science fiction seizes the imaginations of young readers with its tales of the future and of outer space. Talks about various nonfiction books about space. Elaborates a workshop on books about space exploration. Gives 10 questions about stimulating student response. (PA)

Jordan, Anne Devereaux

1997-01-01

20

"Space, the Final Frontier"; Books on Space and Space Exploration.  

ERIC Educational Resources Information Center

|Advocates play in a child's life. Describes how science fiction seizes the imaginations of young readers with its tales of the future and of outer space. Talks about various nonfiction books about space. Elaborates a workshop on books about space exploration. Gives 10 questions about stimulating student response. (PA)|

Jordan, Anne Devereaux

1997-01-01

21

NASA Robotics for Space Exploration.  

National Technical Information Service (NTIS)

This presentation focuses on NASA's use of robotics in support of space exploration. The content was taken from public available websites in an effort to minimize any ITAR or EAR issues. The agenda starts with an introduction to NASA and the 'Vision for S...

R. I. T. Fischer

2007-01-01

22

Power systems for space exploration  

SciTech Connect

The Outreach Program was designed to solicit creative ideas from academia, research institutions, private enterprises, and the general public and is intended to be helpful in defining promising technical areas and program paths for more detailed study. To the Outreach Program, a number of power system concepts were proposed. In conclusion, there are a number of advanced concepts for space power and propulsion sources that deserve study if we want to expand our ability to not only explore space, but to utilize it. Advanced nuclear concepts and power beaming concepts are two areas worthy of detailed assessments.

Shipbaugh, C.; Solomon, K.A.

1992-01-01

23

Robotic Exploration of Space Timeline  

NSDL National Science Digital Library

The invention of the telescope forever changed astronomy by allowing exploration of the universe in far greater detail than was possible with human eyes alone. Technological advances of the twentieth century, such as computers, rockets, and other scientific instruments made even more detailed views of the universe possible. In this interactive timeline from NASA, users can follow the development of rocketry and space exploration from early research by Russian schoolteacher Konstantin Tsiolkovsky and American Robert Goddard through the arrival of the Cassini-Huygens probe in orbit around Saturn in 2004.

24

Propellant Depots: The Future of Space Exploration  

NASA Astrophysics Data System (ADS)

NASA is currently exploring several options for mankind's return to the lunar surface and beyond. The selected option must stimulate both commercial and international involvement, support future missions to the Moon and other destinations, and above all, fit within the current budget profile. Contrary to the current Constellation approach, this paper describes the option of using an in-space propellant depot architecture that can refuel or top-off visiting vehicles at EML1, and how it fits within NASA's new space exploration criteria. In addition to receiving and transferring fuel, the propellant depot will also provide cryogenic propellant storage and management that utilizes flight proven technologies in conjunction with technologies currently under development. The propellant depot system, propellant management and acquisition devices, thermodynamic analysis, and key enabling technologies are also discussed. Depot design concepts along with an overview of a future lunar mission sequence are also presented.

Crenwelge, Drew

25

The business of space exploration  

NASA Astrophysics Data System (ADS)

Despite healthy economic conditions worldwide, aerospace companies have been struggling since the end of the Cold War. The industry faces a very uncertain future as people and money are leaving in droves. But that has not diminished interest in significantly opening up the space frontier for commercial uses. Is there a major disconnect between expectation and reality? What can the Government and private sectors do to positively shape the future? This paper examines the market forces in play and uses the development of the commercial air transportation business to assess the prospect for commercial space transportation and exploration. It also addresses the elements and criteria for business opportunity, and suggests ways in which the public and private sector can work together to build the future of space. .

Tam, Daniel C.

2001-02-01

26

The Vision for Space Exploration  

NASA Astrophysics Data System (ADS)

The Vision, announced by President Bush in January 2004, will extend humanity's presence across the solar system, starting with a return to the moon by the end of the next decade, followed by journeys to Mars and beyond. Building on the best of Apollo and shuttle technology, NASA's 21st century exploration system will be affordable, reliable, versatile and safe. The exploratory voyages of the next few decades have the potential, in this lifetime, to answer age-old questions about how life begins, whether life exists elsewhere, and how the inevitable discoveries along the way will help better our lives here on Earth. Over the next century, the Vision for Space Exploration will set in motion activities to improve our understanding of age-old questions, and inspire new generations to pursue math and science. We'll see new industries and technologies evolve and discoveries that will benefit all.

Griffin, M.

2005-12-01

27

DIPS Space Exploration Initiative safety  

NASA Astrophysics Data System (ADS)

The Dynamic Isotope Power Subsystem has been identified for potential applications for the Space Exploration Initiative. A qualitative safety assessment has been performed to demonstrate the overall safety adequacy of the Dynamic Isotope Power Subsystem for these applications. Mission profiles were defined for reference lunar and Martian flights. Accident scenarios were qualitatively defined for all mission phases. Safety issue were then identified. The safety issues included radiation exposure, fuel containment, criticality, diversion, toxic materials, heat flux to the extravehicular mobility unit, and disposal. The design was reviewed for areas where safety might be further improved. Safety would be improved by launching the fuel separate from the rest of the subsystem on expendable launch vehicles, using a fuel handling tool during unloading of the hot fuel canister, and constructing a cage-like structure around the reversible heat removal system lithium heat pipes. The results of the safety assessment indicate that the DIPS design with minor modifications will produce a low risk concept.

Dix, Terry E.

28

DIPS space exploration initiative safety  

NASA Astrophysics Data System (ADS)

The Dynamic Isotope Power Subsystem has been identified for potential applications for the Space Exploration Initiative. A qualitative safety assessment has been performed to demonstrate the overall safety adequacy of the Dynamic Isotope Power Subsystem for these applications. Mission profiles were defined for reference lunar and martian flights. Accident scenarios were qualitatively defined for all mission phases. Safety issues were then identified. The safety issues included radiation exposure, fuel containment, criticality, diversion, toxic materials, heat flux to the extravehicular mobility unit, and disposal. The design was reviewed for areas where safety might be further improved. Safety would be improved by launching the fuel separate from the rest of the subsystem on expendable launch vehicles, using a fuel handling tool during unloading of the hot fuel canister, and constructing a cage-like structure around the reversible heat removal system lithium heat pipes. The results of the safety assessment indicate that the DIPS design with minor modifications will produce a low risk concept.

Dix, Terry E.

1991-01-01

29

Parallel Global Aircraft Configuration Design Space Exploration  

Microsoft Academic Search

The preliminary design space exploration for large, interdisciplinary engineering problems is often a difficult and time-consuming task. General techniques are needed that efficiently and methodically search the design space. This work focuses on the use of parallel load balancing techniques integrated with a global optimizer to reduce the computational time of the design space exploration. The method is applied to

CHUCK A. BAKER; LAYNE T. WATSON; BERNARD GROSSMAN; WILLIAM H. MASON; RAPHAEL T. HAFTKA

1999-01-01

30

Exploring outer space technologies for sustainable buildings  

Microsoft Academic Search

Purpose – The purpose of this paper is to explore and identify the potential outer space technologies that can be used in the construction industry to enhance sustainability in buildings. Design\\/methodology\\/approach – Outer space technologies developed by the National Aeronautics and Space Administration (NASA) in the USA are explored for possible use in sustainable construction within the context of the

Sui Pheng Low; Xiu Ting Goh

2010-01-01

31

Exploring the Galaxy using space probes  

Microsoft Academic Search

This paper investigates the possible use of space probes to explore the Milky Way, as a means both of finding life elsewhere in the Galaxy and as finding an answer to the Fermi paradox. I simulate exploration of the Galaxy by first examining how long time it takes a given number of space probes to explore 40,000 stars in a

R. Bjørk

32

Exploring the Galaxy using space probes  

Microsoft Academic Search

This paper investigates the possible use of space probes to explore the Milky Way, as a means both of finding life elsewhere in the Galaxy and as finding an answer to the Fermi paradox. Exploration of the Galaxy is simulated by first examining how long time it takes a given number of space probes to explore 40000 stars in a

R. Bjørk

2007-01-01

33

Global visions for space exploration education  

NASA Astrophysics Data System (ADS)

The National Space Biomedical Research Institute (NSBRI), established in 1997 through a National Aeronautics and Space Administration (NASA) competition, is a 12-university consortium dedicated to space life science research and education. NSBRI's Education and Public Outreach Program (EPOP) has partnered with Morehouse School of Medicine (MSM) to support NSBRI-NASA's education mission, which is to strengthen the nation's future science workforce through initiatives that communicate space exploration biology research findings to schools; support undergraduate and graduate programs; fund postdoctoral fellowships; and engage national and international audiences in collegial exchanges that promote global visions for space exploration education. This paper describes select MSM-NSBRI-EPOP activities, including scholarly interchanges with audiences in Austria, Canada, France, China, Greece, Italy, Scotland and Spain. The paper also makes the case for a global space exploration education vision that inspires students, engages educators and informs general audiences about the benefits that space exploration holds for life on Earth.

MacLeish, Marlene Y.; Thomson, William A.

2010-04-01

34

BiSpace Planning: Concurrent Multi-Space Exploration  

Microsoft Academic Search

We present a planning algorithm called BiSpace that produces fast plans to complex high-dimensional problems by simultaneously exploring multiple spaces. We specifically focus on finding robust solutions to manipulation and grasp planning problems by using BiSpace's special characteristics to explore the work and configuration spaces of the environment and robot. Furthermore, we present a number of techniques for constructing informed

Rosen Diankov; Nathan Ratliff; Dave Ferguson; Siddhartha Srinivasa; James Kuffner

35

Why Do We Explore Space?  

Microsoft Academic Search

The launch of the Soviet Sputnik satellite in 1957 challenged the American space enterprise to a race for political and technological superiority. During the Cold War era, the space program had a very clear goal - to show the world that we were the premier force and player in this new frontier. The American public could, therefore, relate to such

E. W. Ng; J. W. Skiles

2006-01-01

36

Design space exploration using the genetic algorithm  

Microsoft Academic Search

A typical VLSI layout problem involves the simultaneous optimization of a number of competing criteria. Rather than generating a single compromise solution, some recent approaches explicitly explores the design space and outputs a set of alternative solutions, thereby providing explicit information on the possible tradeoffs. This paper discuss the use of genetic algorithms (GAs) for design space exploration and propose

Henrdk Esbensen; Ernest S. Kuh

1996-01-01

37

Exploring the Galaxy using space probes  

Microsoft Academic Search

This paper investigates the possible use of space probes to explore the Milky\\u000aWay, as a means both of finding life elsewhere in the Galaxy and as finding an\\u000aanswer to the Fermi paradox. I simulate exploration of the Galaxy by first\\u000aexamining how long time it takes a given number of space probes to explore\\u000a40,000 stars in a

Rasmus Bjoerk

2007-01-01

38

Human Space Exploration architecture study in TAS-I  

NASA Astrophysics Data System (ADS)

The international space exploration plans foresee in the next decades multiple robotic and human missions to Moon, Mars and asteroids. The US Space Exploration program addresses the objective "to explore space and extend a human presence across the Solar System". Main steps include the completion of the International Space Station and its utilization in support of space exploration goals, "as the launching point for missions beyond the Low Earth Orbit". Along a parallel matching path, Europe has developed a roadmap for exploration - Aurora - and has supported design activities on combined Moon-Mars Exploration Architectures. Thales Alenia Space - Italia has been involved in the major European activities related to exploration and it is currently analyzing the different exploration scenarios considered by the major Space Agencies with the objective to identify an international reference scenario for exploration taking into account the need to balance collaboration at international level due to the highly demanding nature of planetary exploration missions, and the development of autonomous key capabilities considered of strategic importance.

Perino, M. A.

39

Power systems for space exploration  

Microsoft Academic Search

The Outreach Program was designed to solicit creative ideas from academia, research institutions, private enterprises, and the general public and is intended to be helpful in defining promising technical areas and program paths for more detailed study. To the Outreach Program, a number of power system concepts were proposed. In conclusion, there are a number of advanced concepts for space

Calvin Shipbaugh; Kenneth A. Solomon

1992-01-01

40

Efficient design space exploration in PICO  

Microsoft Academic Search

Automated design tools must understand and exploit the hierarchical structure of large design spaces. We have developed a general methodology for decomposing system design spaces into smaller component design spaces, followed by component-level evaluation, filtering, recomposition and system-level evaluation. This methodology greatly reduces the time and cost of design space exploration, since the typical number of system-level evaluations is greatly

Santosh G. Abraham; B. Ramakrishna Rau

2000-01-01

41

Innovative Explorer Mission to Interstellar Space  

NASA Astrophysics Data System (ADS)

A mission to interstellar space has been under discussion for over 25 years. Many fundamental scientific questions about the nature of the surrounding galactic medium and its interaction with the solar system can only be answered by in situ measurements that such a mission would provide. The technical difficulties and budgetary and programmatic realities have prevented implementation of previous studies based on the use of a near-Sun perihelion propulsive maneuver, solar sails, and large fission-reactor-powered nuclear electric propulsion systems. We present an alternative approach - the Innovative Interstellar Explorer - based on Radioisotope Electric Propulsion. A high-energy, current-technology launch of the small spacecraft is followed by long-term, lowthrust, continuous acceleration enabled by a kilowatt-class ion thruster powered by Pu-238 Stirling radioisotope generators. We describe the science, payload, and mission and spacecraft design. We also discuss the role such a mission plays in assessing heliospheric “space climate,” knowledge of which is vital for human exploration to Mars and beyond.

Gruntman, M.; McNutt, R. L., Jr.; Gold, R. E.; Krimigis, S. M.; Roelof, E. C.; Leary, J. C.; Gloeckler, G.; Koehn, P. L.; Kurth, W. S.; Oleson, S. R.; Fiehler, D.

42

Toward a global space exploration program: A stepping stone approach  

NASA Astrophysics Data System (ADS)

In response to the growing importance of space exploration in future planning, the Committee on Space Research (COSPAR) Panel on Exploration (PEX) was chartered to provide independent scientific advice to support the development of exploration programs and to safeguard the potential scientific assets of solar system objects. In this report, PEX elaborates a stepwise approach to achieve a new level of space cooperation that can help develop world-wide capabilities in space science and exploration and support a transition that will lead to a global space exploration program. The proposed stepping stones are intended to transcend cross-cultural barriers, leading to the development of technical interfaces and shared legal frameworks and fostering coordination and cooperation on a broad front. Input for this report was drawn from expertise provided by COSPAR Associates within the international community and via the contacts they maintain in various scientific entities. The report provides a summary and synthesis of science roadmaps and recommendations for planetary exploration produced by many national and international working groups, aiming to encourage and exploit synergies among similar programs. While science and technology represent the core and, often, the drivers for space exploration, several other disciplines and their stakeholders (Earth science, space law, and others) should be more robustly interlinked and involved than they have been to date. The report argues that a shared vision is crucial to this linkage, and to providing a direction that enables new countries and stakeholders to join and engage in the overall space exploration effort. Building a basic space technology capacity within a wider range of countries, ensuring new actors in space act responsibly, and increasing public awareness and engagement are concrete steps that can provide a broader interest in space exploration, worldwide, and build a solid basis for program sustainability. By engaging developing countries and emerging space nations in an international space exploration program, it will be possible to create a critical bottom-up support structure to support program continuity in the development and execution of future global space exploration frameworks. With a focus on stepping stones, COSPAR can support a global space exploration program that stimulates scientists in current and emerging spacefaring nations, and that will invite those in developing countries to participate—pursuing research aimed at answering outstanding questions about the origins and evolution of our solar system and life on Earth (and possibly elsewhere). COSPAR, in cooperation with national and international science foundations and space-related organizations, will advocate this stepping stone approach to enhance future cooperative space exploration efforts.

Ehrenfreund, Pascale; McKay, Chris; Rummel, John D.; Foing, Bernard H.; Neal, Clive R.; Masson-Zwaan, Tanja; Ansdell, Megan; Peter, Nicolas; Zarnecki, John; Mackwell, Steve; Perino, Maria Antionetta; Billings, Linda; Mankins, John; Race, Margaret

2012-01-01

43

The Scientific Case for Human Space Exploration  

NASA Astrophysics Data System (ADS)

Many scientists are skeptical about the scientific value of sending people into space, arguing that its high cost would be better invested in additional robotic missions. Here I argue that this skepticism is misplaced, and that the history of human space exploration, particularly of the Apollo Project, indicates that science has actually been a major beneficiary of having people in space. I argue that the same will be true of future human missions to both the Moon and Mars, and that scientific exploration will benefit enormously from exploiting the infrastructure that is developed to support human space activities.

Crawford, I. A.

2001-08-01

44

Material flammability in space exploration atmospheres  

NASA Astrophysics Data System (ADS)

In order to reduce the risk of decompression sickness associated with extravehicular activity, NASA is designing the next generation of exploration vehicles with a different cabin pressure and oxygen concentration than used previously. This work explores how the flammability of solid materials changes in this new environment. One method to evaluate material flammability is by its ease of ignition. To this end, piloted ignition delay tests were conducted in a small-scale wind tunnel subject to this new space exploration atmosphere (SEA -- 58.6 kPa and 32% oxygen) and compared to similar tests in standard atmospheric conditions. In these tests, polymethylmethacylate (PMMA) was exposed to a range of oxidizer flow velocities and externally applied heat fluxes. It was found that the ignition time was reduced by 27% in the intended space exploration atmosphere. It was also noted that the critical heat flux for ignition decreases in exploration atmospheres. These results show that materials are more susceptible to ignition than in current spacecraft atmospheres. To further explore the effect of pressure and oxygen concentration, tests were performed for a wide range of pressures and oxygen concentrations. In all oxygen concentrations tested, the ignition delay time was seen to decrease with pressure, reach a minimum, and then increase with further reduction in pressure creating a classic u-shaped curve. No ignition was seen at sufficiently low pressures. The no ignition pressure depended on the oxygen concentration. Increasing the oxygen concentration uniformly decreases the ignition time; however, no significant differences were seen in oxygen concentrations above 24%. These results indicate there are several competing mechanisms controlling the ignition time. By reducing the pressure, the heat transfer coefficient and the mass flow rate of fuel to reach the lean flammability limit are reduced. Conversely, a reduction in pressure increases the gas-phase chemical induction time. The competition between these three mechanisms is responsible for the u-shaped dependence of ignition time on total pressure. In addition to gaining insight into the effect of pressure on piloted ignition, these results have practical applications including high altitude structures and airplane cabins.

McAllister, Sara Suzanne

45

Technology transfer from the space exploration initiative  

SciTech Connect

Space exploration has demonstrated that it stimulates the national economy by creating new and improved products, increased employment, and provides a stimulus to education. The exploration of the Moon and Mars under the Space Exploration Initiative has the potential of accelerating this stimulates to the economy. It is difficult to identify all of the concrete ways this will be accomplished. However, many areas can be identified. The space exploration building blocks of power, propulsion, spacecraft, robotics, rovers, mining and manufacturing, communications, navigation, habitats, life support and infrastructures are reviewed to identify possible technology areas. For example, better means for working in hazardous areas and handling hazardous waste are potential outcomes of this initiative. Methods to produce higher quality goods and improve America's competitiveness in manufacturing will undoubtedly evolve from the need to produce products that must last many years in the harsh environments of space and planetary surfaces. Some ideas for technology transfer are covered in this paper.

Buden, D.

1991-06-14

46

Technology transfer from the space exploration initiative  

SciTech Connect

Space exploration has demonstrated that it stimulates the national economy by creating new and improved products, increased employment, and provides a stimulus to education. The exploration of the Moon and Mars under the Space Exploration Initiative has the potential of accelerating this stimulates to the economy. It is difficult to identify all of the concrete ways this will be accomplished. However, many areas can be identified. The space exploration building blocks of power, propulsion, spacecraft, robotics, rovers, mining and manufacturing, communications, navigation, habitats, life support and infrastructures are reviewed to identify possible technology areas. For example, better means for working in hazardous areas and handling hazardous waste are potential outcomes of this initiative. Methods to produce higher quality goods and improve America`s competitiveness in manufacturing will undoubtedly evolve from the need to produce products that must last many years in the harsh environments of space and planetary surfaces. Some ideas for technology transfer are covered in this paper.

Buden, D.

1991-06-14

47

An exploration of leakage current  

Microsoft Academic Search

A simple programmable sequence of measurements which allows classification of leakage currents of capacitors based on their time, temperature, and voltage characteristics has been devised. The method adopts the concept that the measured current is the sum of independent flow mechanisms, one of which is present to a consistent extent in all the capacitors. By removal of this part from

R. W. Franklin

1990-01-01

48

Advances in Autonomous Systems for Missions of Space Exploration  

Microsoft Academic Search

New missions of space exploration will require unprecedented levels of autonomy to successfully accomplish their objectives. Both inherent complexity and communication distances will preclude levels of human involvement common to current and previous space flight missions. With exponentially increasing capabilities of computer hardware and software, including networks and communication systems, a new balance of work is being developed between humans

A. R. Gross; B. D. Smith; G. A. Briggs; J. Hieronymus; D. J. Clancy

2002-01-01

49

Design Space Exploration of Network Processor Architectures  

Microsoft Academic Search

We describe an approach to explore the design space for architectures of packet processing devices on the sys- tem level. Our method is specific to the application domain of packet processors and is based on (1) models for packet processing tasks, a specification of the workload generated by traffic streams, and a description of the feasible space of architectures including

Lothar Thiele; Samarjit Chakraborty; Matthias Gries; Simon Kunzli

2002-01-01

50

Heavy ion carcinogenesis and human space exploration  

Microsoft Academic Search

Before the human exploration of Mars or long-duration missions on the Earth's moon, the risk of cancer and other diseases from space radiation must be accurately estimated and mitigated. Space radiation, comprised of energetic protons and heavy nuclei, has been shown to produce distinct biological damage compared with radiation on Earth, leading to large uncertainties in the projection of cancer

Marco Durante; Francis A. Cucinotta

2008-01-01

51

Zack Crues on Space Exploration Vehicle Mockup  

NASA Video Gallery

Zack Crues, the Space Exploration Vehicle modeling and simulation lead, talks to NASA Public Affairs Officer Brandi Dean about the importance of creating an immersive virtual reality environment for tests such as the simulated mission to an asteroid taking place at the Johnson Space Center in Houston.

John Kossum

2012-01-20

52

‘Explorers’ – Star Trek: Deep Space Nine  

Microsoft Academic Search

This article examines race in a Star Trek: Deep Space Nine episode entitled ‘Explorers’. This Star Trek™ spin-off's lead character, named Benjamin Sisko, is of African descent. Sisko must safeguard a fragile peace between Bajorans and Cardassians and secure the commercial and strategic rights to the galaxy's only known stable wormhole, a gateway beyond the Alpha quadrant. In ‘Explorers’ Sisko

Micheal Charles Pounds

2009-01-01

53

Conference on Advanced Space Exploration Initiative Technologies  

Microsoft Academic Search

In striving to reduce exploration cost and exploration risks, a crucial aspect of the plans is program continuity, i.e., the continuing application of a given technology over a long period so that experience will accumulate from extended testing here on Earth and from a diversity of applications in space. An integrated view needs to be formed of the missions SEI

1991-01-01

54

Human exploration and development of space: using XML database Space Wide Web: Space Wide Web by adapters in distributed systems configuration from reusable components  

Microsoft Academic Search

Human exploration and development of space will involve opening the space frontier by exploring, using and enabling the development of space through information technology, while expanding the human experience into the far reaches of space. At that point in time we assert that the current primitive World Wide Web (Web) will be replaced and dramatically expanded into an Interstellar Space

David Rine

2003-01-01

55

Cross-cultural management supporting global space exploration  

NASA Astrophysics Data System (ADS)

A new era of space exploration has begun that may soon expand into a global endeavor mainly driven by socio-economic motives. Currently the main space powers, namely the United States, Russia, Europe, Japan, Canada as well as new rising space powers China and India, are pursuing national exploration programs to explore robotically and later with humans the Earth-Moon-Mars space. New axes of partnerships and cooperation mechanisms have emerged in the last decades. However, in order to achieve highly ambitious goals such as establishing human bases on the Moon, journeys to Mars and the construction of new infrastructures in space, international space cooperation has to be optimized to reduce costs and reap the benefits of worldwide expertise. Future ambitious space exploration endeavors are a long-term undertaking that could influence countries to look beyond their own interests and see the advantages that a larger program can bring. This paper provides new concepts for managing global space exploration in the framework of cross-cultural management, an element often neglected in the planning of future partnerships.

Ehrenfreund, P.; Peter, N.; Schrogl, K. U.; Logsdon, J. M.

2010-01-01

56

Life sciences issues affecting space exploration.  

PubMed

The U.S. space program is undertaking a serious examination of new initiatives in human space exploration involving permanent colonies on the Moon and an outpost on Mars. Life scientists have major responsibilities to the crew, to assure their health, productivity, and safety throughout the mission and the postflight rehabilitation period; to the mission, to provide a productive working environment; and to the scientific community, to advance knowledge and understanding of human adaptation to the space environment. Critical areas essential to the support of human exploration include protection from the radiation hazards of the space environment, reduced gravity countermeasures, artificial gravity, medical care, life support systems, and behavior, performance, and human factors in an extraterrestrial environment. Developing solutions to these concerns is at the heart of the NASA Life Sciences ground-based and flight research programs. Facilities analogous to planetary outposts are being considered in Antarctica and other remote settings. Closed ecological life support systems will be tested on Earth and Space Station. For short-duration simulations and tests, the Space Shuttle and Spacelab will be used. Space Station Freedom will provide the essential scientific and technological research in areas that require long exposures to reduced gravity conditions. In preparation for Mars missions, research on the Moon will be vital. As the challenges of sustaining humans on space are resolved, advances in fundamental science, medicine and technology will follow. PMID:11541483

White, R J; Leonard, J I; Leveton, L; Gaiser, K; Teeter, R

1990-12-01

57

The virtual space exploration education portal  

NASA Astrophysics Data System (ADS)

New information technologies have evolved from space exploration—3-D visualisation ‘lenses’ and a growing suite of tools that allow access to exploration, analysis and interpretation of often complex information by a range of end users including the public, communicators, and policy makers. These tools have only become viable in the past year or two with the combination of the availability of inexpensive, but powerful, personal computers and widespread use of the Internet. A new study group under Commission 6 has been established, entitled ‘Future Directions of Space Exploration Education’, to build a Virtual Global Space Exploration Education Portal (VGSEEP) to open this revolution to all audiences, not just students. This paper describes the initial stages of VGSEEP. The NASA Learning Technologies suite of ‘lenses’ and tools will be demonstrated: World Wind, a 3-D globe that provides insights into our planet from space and almost down to ground level; the Virtual Field Trip that explores at ground level in 3-D; the Virtual Lab, which allows a range of samples to be examined via a virtual light microscope and/or a Scanning Electron Microscope and What’s the Difference?, which allows users to manipulate information in a multi-graphical interface.

Oliver, C. A.

2007-06-01

58

Mars exploration invites global space cooperation  

NASA Astrophysics Data System (ADS)

A conference of space scientists, engineers, and managers was held at Wiesbaden, Germany on May 10-11, 1993, in order to foster coordination among agencies interested in Mars exploration in the late 1990s and early 2000s. The international planning thus initiated for unmanned flights is expected to lead the way to eventual multinational (U.S., European, Russian, and Japanese) Mars exploration. Attention is presently given to the robotic technologies whose development is required for these ventures.

Covault, Craig

59

Power efficient mediaprocessors: design space exploration  

Microsoft Academic Search

We present a framework for rapidly exploring the design space of low power application-specific programmable processors (ASPP), in particular mediaprocessors. We focus on a category of proces- sors that are programmable yet optimized to reduce power con- sumption for a specific set of applications. The key components of the framework presented in this paper are a retargetable instruction level parallelism

Johnson Kin; Chunho Lee; William H. Mangione-Smith; Miodrag Potkonjak

1999-01-01

60

Design space exploration of streaming multiprocessor architectures  

Microsoft Academic Search

In this paper, we present a comparison of two design-space exploration approaches. The comparison is in terms of (1) speed of simulation versus accuracy of performance numbers, and (2) connection to trajectories for detailed design. The two approaches are: the trace driven approach and the control data flow graph approach. The first approach leads to the shortest simulation time, but

V. D. Zivkovic; Ed Deprettere; P. van der Wolf; E. de Kock

2002-01-01

61

Advanced Regenerative Life Support for Space Exploration.  

National Technical Information Service (NTIS)

Advanced regenerative Environmental Control and Life Support System (ECLSS) technology was identified by NASA as enabling for space exploration. Low Earth Orbit (LEO) mass savings of over 700,000 pounds (320,000 kg) per year are expected for a lunar outpo...

H. T. Couch J. W. Auman T. C. Falvey

1991-01-01

62

Trade space exploration: New Visual Steering features  

Microsoft Academic Search

The Applied Research Laboratory at Penn State University has a long history of developing software tools to support decision-making within the conceptual stage of complex systems design. Previous research introduced a new approach to trade space exploration called Visual Steering. This approach combines exercising a design model and analyzing the results into a tightly coupled loop that lets decision makers

Sara E. Lego; Gary M. Stump; Mike Yukish

2010-01-01

63

Exploring the chemical space of aromatase inhibitors.  

PubMed

Aromatase, a rate-limiting enzyme catalyzing the conversion of androgen to estrogen, is overexpressed in human breast cancer tissue. Aromatase inhibitors (AIs) have been used for the treatment of estrogen-dependent breast cancer in post-menopausal women by blocking the biosynthesis of estrogen. The undesirable side effects in current AIs have called for continued pursuit for novel candidates with aromatase inhibitory properties. This study explores the chemical space of all known AIs as a function of their physicochemical properties by means of univariate (i.e., statistical and histogram analysis) and multivariate (i.e., decision tree and principal component analysis) approaches in order to understand the origins of aromatase inhibitory activity. Such a non-redundant set of AIs spans a total of 973 compounds encompassing both steroidal and non-steroidal inhibitors. Substructure analysis of the molecular fragments provided pertinent information on the structural features important for ligands providing high and low aromatase inhibition. Analyses were performed on data sets stratified according to their structural scaffolds (i.e., steroids and non-steroids) and bioactivities (i.e., actives and inactives). These analyses have uncover a set of rules characteristic to active and inactive AIs as well as revealing the constituents giving rise to potent aromatase inhibition. PMID:23857318

Nantasenamat, Chanin; Li, Hao; Mandi, Prasit; Worachartcheewan, Apilak; Monnor, Teerawat; Isarankura-Na-Ayudhya, Chartchalerm; Prachayasittikul, Virapong

2013-07-16

64

Astrobiological Benefits of Human Space Exploration  

NASA Astrophysics Data System (ADS)

An ambitious program of human space exploration, such as that envisaged in the Global Exploration Strategy and considered in the Augustine Commission report, will help advance the core aims of astrobiology in multiple ways. In particular, a human exploration program will confer significant benefits in the following areas: (i) the exploitation of the lunar geological record to elucidate conditions on early Earth; (ii) the detailed study of near-Earth objects for clues relating to the formation of the Solar System; (iii) the search for evidence of past or present life on Mars; (iv) the provision of a heavy-lift launch capacity that will facilitate exploration of the outer Solar System; and (v) the construction and maintenance of sophisticated space-based astronomical tools for the study of extrasolar planetary systems. In all these areas a human presence in space, and especially on planetary surfaces, will yield a net scientific benefit over what can plausibly be achieved by autonomous robotic systems. A number of policy implications follow from these conclusions, which are also briefly considered.

Crawford, Ian A.

2010-08-01

65

[Consequences of space exploration for mankind].  

PubMed

Space exploration obliges man to confront a hostile environment of cosmic radiation, microgravity, and magnetic field changes. Although the people who will go to Mars have been born, many new discoveries will be needed and new disciplines will have to be created before they can actually go there. All of this will have a tremendous impact on our health technology. For one thing, universities will work together with enterprises, creating a new way to carry out research. Space exploration has already generated new insight into osteoporosis, muscle atrophy, and motor coordination disorders. Space research has produced a long list of utilities including bone fixation devices and wheelchairs. Over the next 5 to 7 years, in the International Space Station many programs ranging from molecular biology to direct observation of human subjects will be developed. This will mean that, while awaiting the first expedition to Mars (which will take place after 2080), the collaboration of scientists with small and medium enterprises will continue to produce useful devices for people on earth. PMID:19048568

Bizzarri, M

66

Abstracting Attribute Space for Transfer Function Exploration and Design.  

PubMed

Currently, user centered transfer function design begins with the user interacting with a one or two-dimensional histogram of the volumetric feature space. The feature space is visualized as a function of the number of voxels, allowing the user to explore the data in terms of the feature size/magnitude. However, such visualizations provide the user with no information on the relationship between the feature space and the volumetric space. We propose a modification to the feature space visualization in which the user is no longer presented with the magnitude of the feature; instead, the user is presented with an information metric detailing the relationship between the feature space and the volumetric space. In this way, the user can guide their exploration based on the relationship between the feature magnitude and the spatial information as opposed to being constrained by only visualizing the magnitude of the feature. Our system utilizes common one and two-dimensional histogram widgets where the bins of the abstract feature space now correspond to a feature relationship in terms of the spatial mean, standard deviation, entropy, or skewness. In this manner, we exploit the relationships and correlations present in the underlying data with respect to the dimension(s) under examination. PMID:22508900

Maciejewski, Ross; Jang, Yun; Woo, Insoo; Janicke, Heike; Gaither, Kelly P; Ebert, David S

2012-04-10

67

Interactive Exploration of Neuroanatomical Meta-Spaces  

PubMed Central

Large-archives of neuroimaging data present many opportunities for re-analysis and mining that can lead to new findings of use in basic research or in the characterization of clinical syndromes. However, interaction with such archives tends to be driven textually, based on subject or image volume meta-data, not the actual neuroanatomical morphology itself, for which the imaging was performed to measure. What is needed is a content-driven approach for examining not only the image content itself but to explore brains that are anatomically similar, and identifying patterns embedded within entire sets of neuroimaging data. With the aim of visual navigation of large- scale neurodatabases, we introduce the concept of brain meta-spaces. The meta-space encodes pair-wise dissimilarities between all individuals in a population and shows the relationships between brains as a navigable framework for exploration. We employ multidimensional scaling (MDS) to implement meta-space processing for a new coordinate system that distributes all data points (brain surfaces) in a common frame-of-reference, with anatomically similar brain data located near each other. To navigate within this derived meta-space, we have developed a fully interactive 3D visualization environment that allows users to examine hundreds of brains simultaneously, visualize clusters of brains with similar characteristics, zoom in on particular instances, and examine the surface topology of an individual brain's surface in detail. The visualization environment not only displays the dissimilarities between brains, but also renders complete surface representations of individual brain structures, allowing an instant 3D view of the anatomies, as well as their differences. The data processing is implemented in a grid-based setting using the LONI Pipeline workflow environment. Additionally users can specify a range of baseline brain atlas spaces as the underlying scale for comparative analyses. The novelty in our approach lies in the user ability to simultaneously view and interact with many brains at once but doing so in a vast meta-space that encodes (dis) similarity in morphometry. We believe that the concept of brain meta-spaces has important implications for the future of how users interact with large-scale archives of primary neuroimaging data.

Joshi, Shantanu H.; Horn, John Darrell Van; Toga, Arthur W.

2009-01-01

68

Reactor safety for the space exploration initiative  

SciTech Connect

A task force was created by the National Aeronautics and Space Administration to conduct a 90-day study to support efforts to determine requirements to meet the goals of the Space Exploration Initiative. The task force identified the need for a nuclear reactor to provide the electrical power required as the outpost power demands on the Moon and Mars evolve into hundreds of kilowatts. A preliminary hazards analysis has been performed to examine safety aspects of nuclear reactor power systems for representative missions to the Moon and Mars. Mission profiles were defined for reference lunar and martian flights. Potential alternatives to each mission phase were also defined. Accident scenarios were qualitatively defined for the mission phases. The safety issues decay heat removal, reactor control, disposal, criticality, end-of-mission shutdown, radiation exposure, the martian environment, high speed impact on the surfaces of the Moon or Mars, and return flyby trajectories were identified.

Dix, T.E. (Rockwell International/Rocketdyne Division, 6633 Canoga Avenue, MS HB07, Canoga Park, California 91303 (US))

1991-01-01

69

Deep space environments for human exploration.  

PubMed

Mission scenarios outside the Earth's protective magnetic shield are being studied. Included are high usage assets in the near-Earth environment for casual trips, for research, and for commercial/operational platforms, in which career exposures will be multi-mission determined over the astronaut's lifetime. The operational platforms will serve as launching points for deep space exploration missions, characterized by a single long-duration mission during the astronaut's career. The exploration beyond these operational platforms will include missions to planets, asteroids, and planetary satellites. The interplanetary environment is evaluated using convective diffusion theory. Local environments for each celestial body are modeled by using results from the most recent targeted spacecraft, and integrated into the design environments. Design scenarios are then evaluated for these missions. The underlying assumptions in arriving at the model environments and their impact on mission exposures within various shield materials will be discussed. PMID:15880915

Wilson, J W; Clowdsley, M S; Cucinotta, F A; Tripathi, R K; Nealy, J E; De Angelis, G

2004-01-01

70

Envisioning cognitive robots for future space exploration  

NASA Astrophysics Data System (ADS)

Cognitive robots in the context of space exploration are envisioned with advanced capabilities of model building, continuous planning/re-planning, self-diagnosis, as well as the ability to exhibit a level of 'understanding' of new situations. An overview of some JPL components (e.g. CASPER, CAMPOUT) and a description of the architecture CARACaS (Control Architecture for Robotic Agent Command and Sensing) that combines these in the context of a cognitive robotic system operating in a various scenarios are presented. Finally, two examples of typical scenarios of a multi-robot construction mission and a human-robot mission, involving direct collaboration with humans is given.

Huntsberger, Terry; Stoica, Adrian

2010-04-01

71

Current Soviet exploration plays: Success and potential  

SciTech Connect

Soviet hydrocarbon exploration in the 1980s took four distinct directions. First was extension exploration and the search for smaller new fields in discrete traps in traditional producing regions, such as the Apsheron Peninsula, North Caucasus, and Volga-Urals. This strategy produced a large number of small discoveries close to established infrastructure. Second was new field exploration in West Siberia in the stratigraphically complex Jurassic and the lower Neocomian sections. Third was expansion of the prolific gas plays in northern West Siberia. Exploratory success in West Siberia has created a backlog of several hundred discoveries awaiting full delineation and development. Most of these fields are distant from the established oil production center in the Middle Ob region and, therefore, may remain in inventory. Fourth was initial tests of new exploration frontiers, most important, the Paleozoic and Mesozoic plays of the Barents and Kara seas and the subsalt plays of the North Caspian basin. While these plays have yielded very important discoveries, significant technological barriers impede their development. The outlook for Soviet oil exploration in the 1990s is for significant opportunities for discovery of large volumes of oil, but at radically increasing exploration and production costs. In established regions, these costs arise from small field sizes and low well productivities. In frontier regions, exploitation of new fields will require technology not currently available in the USSR. The outlook for gas exploration continues to be very bright, as the onshore northern West Siberia is not fully explored and initial results from the Barents and Kara seas promise more very large gas discoveries.

Grace, J.D. (ARCO, Los Angeles, CA (United States))

1991-03-01

72

Nuclear safety for the space exploration initiative  

NASA Astrophysics Data System (ADS)

The results of a study to identify potential hazards arising from nuclear reactor power systems for use on the lunar and Martian surfaces, related safety issues, and resolutions of such issues by system design changes, operating procedures, and other means are presented. All safety aspects of nuclear reactor power systems from prelaunch ground handling to eventual disposal were examined consistent with the level of detail for SP-100 reactor design at the 1988 System Design Review and for launch vehicle and space transport vehicle designs and mission descriptions as defined in the 90-day Space Exploration Initiative (SEI) study. Information from previous aerospace nuclear safety studies was used where appropriate. Safety requirements for the SP-100 space nuclear reactor system were compiled. Mission profiles were defined with emphasis on activities after low earth orbit insertion. Accident scenarios were then qualitatively defined for each mission phase. Safety issues were identified for all mission phases with the aid of simplified event trees. Safety issue resolution approaches of the SP-100 program were compiled. Resolution approaches for those safety issues not covered by the SP-100 program were identified. Additionally, the resolution approaches of the SP-100 program were examined in light of the moon and Mars missions.

Dix, Terry E.

1991-11-01

73

Towards a new inspiring era of collaborative space exploration  

Microsoft Academic Search

In recent years, space exploration has topped the agenda of most space-faring countries. This interest in solar system exploration\\u000a can be illustrated by the development of the U.S. Vision for Space Exploration, the European Space Agency (ESA) Aurora programme,\\u000a as well as robotic exploration missions under development in India, China, Japan and Russia. This is completed by the fact\\u000a that

Nicolas Peter

74

Rationale and constituencies for the Space Exploration Initiative  

Microsoft Academic Search

In order to maximize the benefits from prospective space-exploration endeavors, and to enlist the support of as many constituencies as possible, NASA is either conducting or developing programs which emphasize different aspects of the Space Exploration Initiative. Attention is presently given to the cases of education using space exploration themes as teaching tools and technology transfer from government to private

Kristine A. Johnson

1992-01-01

75

Human space exploration – A global trans-cultural quest  

Microsoft Academic Search

This Viewpoint is a slightly edited version of the ‘Statement by Space Explorers on Human Space Exploration’ produced in the wake of a workshop organized by the European Space Policy Institute and held in Vienna in May 2010. While noting the cultural differences in understandings of ‘exploration’ around the world, it also affirms the phenomenon as a globe-wide, human urge,

Sergey Avdeyev; Jean-Francois Clervoy; Jean-Marc Comtois; Takao Doi; Jeffrey Hoffman; Mamoru Mohri; Gerhard Thiele

2011-01-01

76

Space exploration, Mars, and the nervous system.  

PubMed

When human beings venture back to the moon and then on to Mars in the coming decade or so, we will be riding on the accumulated data and experience from approximately 50 years of manned space exploration. Virtually every organ system functions differently in the absence of gravity, and some of these changes are maladaptive. From a biologic perspective, long duration spaceflight beyond low Earth orbit presents many unique challenges. Astronauts traveling to Mars will live in the absence of gravity for more than 1 year en route and will have to transition between weightlessness and planetary gravitational forces at the beginning, middle, and end of the mission. We discuss some of what is known about the effects of spaceflight on nervous system function, with emphasis on the neuromuscular and vestibular systems because success of a Mars mission will depend on their proper functioning. PMID:17420309

Kalb, Robert; Solomon, David

2007-04-01

77

Exploring Space, Exploring Earth: New Understanding of the Earth from Space Research  

NASA Astrophysics Data System (ADS)

This book describes the impact of space flight on geology and geophysics, beginning with a foreword by Neil Armstrong, which illustrates how the exploration of space has lead us to a far deeper understanding of our own planet. Direct results from Earth-orbital missions include studies of Earth's gravity and magnetic fields. In contrast, the recognition of the economic and biological significance of impact craters on Earth is an indirect consequence of the study of the geology of other planets. The final chapter presents a new theory for the tectonic evolution of the Earth based on comparative planetology and the Gaia concept.

Lowman, Paul D., Jr.

2002-08-01

78

Risk management for the Space Exploration Initiative  

NASA Astrophysics Data System (ADS)

Probabilistic Risk Assessment (PRA) is a quantitative engineering process that provides the analytic structure and decision-making framework for total programmatic risk management. Ideally, it is initiated in the conceptual design phase and used throughout the program life cycle. Although PRA was developed for assessment of safety, reliability, and availability risk, it has far greater application. Throughout the design phase, PRA can guide trade-off studies among system performance, safety, reliability, cost, and schedule. These studies are based on the assessment of the risk of meeting each parameter goal, with full consideration of the uncertainties. Quantitative trade-off studies are essential, but without full identification, propagation, and display of uncertainties, poor decisions may result. PRA also can focus attention on risk drivers in situations where risk is too high. For example, if safety risk is unacceptable, the PRA prioritizes the risk contributors to guide the use of resources for risk mitigation. PRA is used in the Space Exploration Initiative (SEI) Program. To meet the stringent requirements of the SEI mission, within strict budgetary constraints, the PRA structure supports informed and traceable decision-making. This paper briefly describes the SEI PRA process.

Buchbinder, Ben

1993-01-01

79

Investigating public space exploration support in the UK  

Microsoft Academic Search

Space agencies such as NASA and ESA have ambitious long-term programmes that mark the beginning of a new era in space exploration where humans will land on Mars; an era requiring public support and, therefore, more consideration for public opinion. Empirical research shows that there are substantial differences in the level of understanding of space exploration among the general public.

Marta Entradas; Steve Miller

2010-01-01

80

Ethical Considerations for Planetary Protection in Space Exploration: A Workshop  

PubMed Central

Abstract With the recognition of an increasing potential for discovery of extraterrestrial life, a diverse set of researchers have noted a need to examine the foundational ethical principles that should frame our collective space activities as we explore outer space. A COSPAR Workshop on Ethical Considerations for Planetary Protection in Space Exploration was convened at Princeton University on June 8–10, 2010, to examine whether planetary protection measures and practices should be extended to protect planetary environments within an ethical framework that goes beyond “science protection” per se. The workshop had been in development prior to a 2006 NRC report on preventing the forward contamination of Mars, although it responded directly to one of the recommendations of that report and to several peer-reviewed papers as well. The workshop focused on the implications and responsibilities engendered when exploring outer space while avoiding harmful impacts on planetary bodies. Over 3 days, workshop participants developed a set of recommendations addressing the need for a revised policy framework to address “harmful contamination” beyond biological contamination, noting that it is important to maintain the current COSPAR planetary protection policy for scientific exploration and activities. The attendees agreed that there is need for further study of the ethical considerations used on Earth and the examination of management options and governmental mechanisms useful for establishing an environmental stewardship framework that incorporates both scientific input and enforcement. Scientists need to undertake public dialogue to communicate widely about these future policy deliberations and to ensure public involvement in decision making. A number of incremental steps have been taken since the workshop to implement some of these recommendations. Key Words: Planetary protection—Extraterrestrial life—Life in extreme environments—Environment—Habitability. Astrobiology 12, 1017–1023.

Rummel, J.D.; Horneck, G.

2012-01-01

81

Ethical considerations for planetary protection in space exploration: a workshop.  

PubMed

With the recognition of an increasing potential for discovery of extraterrestrial life, a diverse set of researchers have noted a need to examine the foundational ethical principles that should frame our collective space activities as we explore outer space. A COSPAR Workshop on Ethical Considerations for Planetary Protection in Space Exploration was convened at Princeton University on June 8-10, 2010, to examine whether planetary protection measures and practices should be extended to protect planetary environments within an ethical framework that goes beyond "science protection" per se. The workshop had been in development prior to a 2006 NRC report on preventing the forward contamination of Mars, although it responded directly to one of the recommendations of that report and to several peer-reviewed papers as well. The workshop focused on the implications and responsibilities engendered when exploring outer space while avoiding harmful impacts on planetary bodies. Over 3 days, workshop participants developed a set of recommendations addressing the need for a revised policy framework to address "harmful contamination" beyond biological contamination, noting that it is important to maintain the current COSPAR planetary protection policy for scientific exploration and activities. The attendees agreed that there is need for further study of the ethical considerations used on Earth and the examination of management options and governmental mechanisms useful for establishing an environmental stewardship framework that incorporates both scientific input and enforcement. Scientists need to undertake public dialogue to communicate widely about these future policy deliberations and to ensure public involvement in decision making. A number of incremental steps have been taken since the workshop to implement some of these recommendations. PMID:23095097

Rummel, J D; Race, M S; Horneck, G

2012-10-24

82

Explorations in Space and Time: Computer-Generated Astronomy Films  

ERIC Educational Resources Information Center

Discusses the use of the computer animation technique to travel through space and time and watch models of astronomical systems in motion. Included is a list of eight computer-generated demonstration films entitled Explorations in Space and Time.'' (CC)

Meeks, M. L.

1973-01-01

83

Management Model for International Participation in Space Exploration Missions.  

National Technical Information Service (NTIS)

This paper proposes an engineering management model for NASA's future space exploration missions based on past experiences working with the International Partners of the International Space Station. The authors have over 25 years of combined experience wo...

P. J. George G. M. Pease T. E. Tyburski

2005-01-01

84

Global visions for space exploration education  

Microsoft Academic Search

The National Space Biomedical Research Institute (NSBRI), established in 1997 through a National Aeronautics and Space Administration (NASA) competition, is a 12-university consortium dedicated to space life science research and education. NSBRI's Education and Public Outreach Program (EPOP) has partnered with Morehouse School of Medicine (MSM) to support NSBRI-NASA's education mission, which is to strengthen the nation's future science workforce

Marlene Y. MacLeish; William A. Thomson

2010-01-01

85

Radiation risk and human space exploration  

Microsoft Academic Search

Radiation protection is essential to enable humans to live and work safely in space. Predictions about the nature and magnitude of the risks posed by space radiation are subject to very large uncertainties. Prudent use of worst-case scenarios may impose unacceptable constraints on shielding mass for spacecraft or habitats, tours of duty of crews on Space Station, and on the

W. Schimmerling; F. A. Cucinotta; J. W. Wilson

2003-01-01

86

Exploring Space Physics Concepts Using Simulation Results  

Microsoft Academic Search

The Center for Integrated Space Weather Modeling (CISM), a Science and Technology Center (STC) funded by the National Science Foundation, has the goal of developing a suite of integrated physics based computer models of the space environment that can follow the evolution of a space weather event from the Sun to the Earth. In addition to the research goals, CISM

N. A. Gross

2008-01-01

87

Symmetric Space ?-MODEL Dynamics:. Current Formalism  

NASA Astrophysics Data System (ADS)

After explicitly constructing the symmetric space sigma model Lagrangian in terms of the coset scalars of the solvable Lie algebra gauge in the current formalism, we derive the field equations of the theory.

Yilmaz, Nejat T.

88

Exploration of Space and the Discovery of the Unintended  

Microsoft Academic Search

This research seeks to understand and define what are called here, unintentional spaces. This research begins by looking into different types of space and spatial intricacies. The intricacies introduced include: representation, perception, value, beauty, and interaction. These initial explorations seek to establish a general understanding and vocabulary for examining unintentional space. Once a basic definition of these spaces is established,

Sheila McLain

2005-01-01

89

Exploration Challenges: Transferring Ground Repair Techniques to Space Flight Application  

NASA Astrophysics Data System (ADS)

Fulfilling NASA's Vision for Space Exploration will demand an extended presence in space at distances from our home planet that exceed our current experience in space logistics and maintenance. The ability to perform repairs in lieu of the customary Orbital Replacement Unit (ORU) process where a faulty part is replaced will be elevated from contingency to routine to sustain operations. The use and cost effectiveness of field repairs for ground based operations in industry and the military have advanced with the development of technology in new materials, new repair techniques and new equipment. The unique environments, accessibility constraints and Extra Vehicular Activity (EVA) issues of space operations will require extensive assessment and evolution of these technologies to provide an equivalent and expected level of assurance to mission success. Challenges include the necessity of changes in design philosophy and policy, extremes in thermal cycling, disruptive forces (such as static charge and wind entrainment) on developed methods for control of materials, dramatically increased volatility of chemicals for cleaning and other compounds due to extremely low pressures, the limits imposed on dexterity and maneuverability by current EVA equipment and practices, and the necessity of unique verification methodology. This paper describes these challenges in and discusses the effects on the established ground techniques for repair. The paper also describes the leading repair methodology candidates and their beneficial attributes for resolving these issues with the evolution of technology.

McLemore, Carole A.; Kennedy, James P.; Rose, Frederick A.; Evans, Brian W.

2007-01-01

90

Nuclear data needs for the space exploration initiative  

SciTech Connect

On July 20, 1989, the President of the United States announced a new direction for the US Space Program. The new Space Exploration Initiative (SEI) is intended to emplace a permanent base on the Lunar surface and a manned outpost on the Mars surface by 2019. In order to achieve this ambitious challenge, new, innovative and robust technologies will have to be developed to support crew operations. Nuclear power and propulsion have been recognized as technologies that are at least mission enhancing and, in some scenarios, mission enabling. Because of the extreme operating conditions present in a nuclear rocket core, accurate modeling of the rocket will require cross section data sets which do not currently exist. In order to successfully achieve the goals of the SEI, major obstacles inherent in long duration space travel will have to be overcome. One of these obstacles is the radiation environment to which the astronauts will be exposed. In general, an unshielded crew will be exposed to roughly one REM per week in free space. For missions to Mars, the total dose could exceed more than one-half the total allowed lifetime level. Shielding of the crew may be possible, but accurate assessments of shield composition and thickness are critical if shield masses are to be kept at acceptable levels. In addition, the entire ship design may be altered by the differential neutron production by heavy ions (Galactic Cosmic Rays) incident on ship structures. The components of the radiation environment, current modeling capability and envisioned experiments will be discussed.

Howe, S.D.; Auchampaugh, G.

1991-01-01

91

Human & robotics technology space exploration communication scenarios: characteristics, challenges & scenarios for developing intelligent Internet protocols  

Microsoft Academic Search

In this paper, we provide a comprehensive view of current and future space communications systems, and scenarios in relation with intelligent Internet protocol (IIP). IIP is an innovative network layer protocol developed to meet the shortcomings of existing Internet protocol (IP) in an adverse space networking environment and provide future communication support for NASA space exploration activities. IIP distinguishes itself

Behnam Malakooti; Hyun Kim; Kul Bhasin

2006-01-01

92

NASA Now Minute: Technology and Design: The Future of Space Exploration  

NASA Video Gallery

John Connolly, deputy manager of the Exploration Missions and Systems Office, describes the physics and environmental differences engineers must consider when designing crewed exploration missions to destinations in space. NASA Now Minutes are excerpts from a weekly current events program available for classroom use at the NASA Explorer Schools Virtual Campus located at: › http://explorerschools.nasa.gov.

Heather Deiss

2012-12-05

93

International Space Station as an Exploration Platform for Deep Space  

NASA Astrophysics Data System (ADS)

We will introduce concepts for how ISS could be fully utilized to support exploration. Pressure on program budgets will only intensify the need to use existing assets to their fullest extent. Meaningful progress on exploration can be made using ISS.

Raftery, M.; Hoffman, J.; Klaus, K.

2012-03-01

94

SPACE AGRICULTURE FOR MANNED SPACE EXPLORATION ON MARS  

Microsoft Academic Search

Concept of space agriculture is discussed for habitation on Mars. Space agriculture enables human to live and survive comfortably with biological and ecological functions. Water and gas are revitalized by photosynthetic process of plants. Hyper-thermophilic aerobic composting bacteria drive recycling loop of metabolic waste of human and inedible biomass to cultivate plants. Trees and insects play important role in space

Masamichi Yamashita; Yoji Ishikawa; Makoto Nagatomo; Tairo Oshima

95

Exploration of RNA Structure Spaces (Abstract Only).  

National Technical Information Service (NTIS)

In order to understand the structure of real structure spaces, we are studying the 5S rRNA structure space experimentally. A plasmid containing a synthetic 5S rRNA gene, two rRNA promoters, and transcription terminators has been assembled. Assays are cond...

G. E. Fox

1991-01-01

96

Interaction Challenges in Human-Robot Space Exploration.  

National Technical Information Service (NTIS)

In January 2004, NASA established a new, long-term exploration program to fulfill the President's Vision for U.S. Space Exploration. The primary goal of this program is to establish a sustained human presence in space, beginning with robotic missions to t...

T. Fong I. Nourbakhsh

2005-01-01

97

Global partnerships: Expanding the frontiers of space exploration education  

NASA Astrophysics Data System (ADS)

Globalization is creating an interdependent space-faring world and new opportunities for international partnerships that strengthen space knowledge development and transfer. These opportunities have been codified in the Global Exploration Strategy, which endorses the "inspirational and educational value of space exploration" [1]. Also, during the 2010 Heads of Space Agencies Summit celebrating the International Academy of Astronautics' (IAA) 50th Anniversary, space-faring nations from across the globe issued a collective call in support of robust international partnerships to expand the frontiers of space exploration and generate knowledge for improving life on Earth [2]. Educators play a unique role in this mission, developing strategic partnerships and sharing best educational practices to (1) further global understanding of the benefits of space exploration for life on Earth and (2) prepare the next generation of scientists required for the 21st Century space workforce. Educational Outreach (EO) programs use evidence-based, measurable outcomes strategies and cutting edge information technologies to transfer space-based science, technology, engineering and mathematics (STEM) knowledge to new audiences; create indigenous materials with cultural resonance for emerging space societies; support teacher professional development; and contribute to workforce development initiatives that inspire and prepare new cohorts of students for space exploration careers. The National Space Biomedical Research Institute (NSBRI), the National Aeronautics and Space Administration (NASA) and Morehouse School of Medicine (MSM) have sustained a 13-year space science education partnership dedicated to these objectives. This paper briefly describes the design and achievements of NSBRI's educational programs, with special emphasis on those initiatives' involvement with IAA and the International Astronautical Congress (IAC). The IAA Commission 2 Draft Report, Space for Africa, is discussed as a model for developing sustainable partnerships and indigenous programs that support Africa's steady emergence as a global space-faring force. The IAC will provide timely: 2011 South Africa will provide timely feedback to refine that report's strategies for space life sciences education and public engagement in Africa and around the globe.

MacLeish, Marlene Y.; Akinyede, Joseph O.; Goswami, Nandu; Thomson, William A.

2012-11-01

98

Radiation risk and human space exploration.  

PubMed

Radiation protection is essential to enable humans to live and work safely in space. Predictions about the nature and magnitude of the risks posed by space radiation are subject to very large uncertainties. Prudent use of worst-case scenarios may impose unacceptable constraints on shielding mass for spacecraft or habitats, tours of duty of crews on Space Station, and on the radius and duration of sorties on planetary surfaces. The NASA Space Radiation Health Program has been devised to develop the knowledge required to accurately predict and to efficiently manage radiation risk. The knowledge will be acquired by means of a peer-reviewed, largely ground-based and investigator-initiated, basic science research program. The NASA Strategic Plan to accomplish these objectives in a manner consistent with the high priority assigned to the protection and health maintenance of crews will be presented. PMID:12577903

Schimmerling, W; Cucinotta, F A; Wilson, J W

2003-01-01

99

Novel Chemical Space Exploration via Natural Products  

PubMed Central

Natural products (NPs) are a rich source of novel compound classes and new drugs. In the present study we have used the chemical space navigation tool ChemGPS-NP to evaluate the chemical space occupancy by NPs and bioactive medicinal chemistry compounds from the database WOMBAT. The two sets differ notable in coverage of chemical space, and tangible lead-like NPs were found to cover regions of chemical space that lack representation in WOMBAT. Property based similarity calculations were performed to identify NP neighbours of approved drugs. Several of the NPs revealed by this method, were confirmed to exhibit the same activity as their drug neighbours. The identification of leads from a NP starting point may prove a useful strategy for drug discovery, in the search for novel leads with unique properties.

Rosen, Josefin; Gottfries, Johan; Muresan, Sorel; Backlund, Anders; Oprea, Tudor I.

2009-01-01

100

The “Vision for Space Exploration” of President George W. Bush, space science, and U.S. space policy  

Microsoft Academic Search

On January 14, 2004 President George W. Bush announced a major overhaul of U.S. space exploration strategy and infrastructure, stipulating that NASA complete the International Space Station (ISS) and retire the Space Shuttle fleet by 2010, develop a new suite of launch and exploration vehicles for deployment shortly thereafter, and embark on a program of human exploration of the solar

Joseph N. Tatarewicz

2009-01-01

101

An Initiative for Organizing International Cooperation in Space Exploration  

NASA Astrophysics Data System (ADS)

It is suggested that at the Beijing COSPAR Assembly in July 2006 a panel meet to discuss the creation of an International Space Exploration Council to provide guidance in preparing future cooperation on space exploration by begin itemize item coordinating ILEWG and IMEWG item analyzing the possibilities of joint actions for the elaboration of an international road map in planetary exploration item implementing cooperative ventures through agencies end itemize

Blamont, J. E.

102

Space Exploration; Power Sources for Deep Space Probes.  

National Technical Information Service (NTIS)

The National Aeronautics and Space Administration (NASA) launched its nuclear powered Cassini spacecraft on October 15, 1997, on a 12 year mission to Saturn. You asked that we review the use of nuclear power systems for Cassini and other space missions. A...

1998-01-01

103

Biomimetics on seed dispersal: survey and insights for space exploration.  

PubMed

Seeds provide the vital genetic link and dispersal agent between successive generations of plants. Without seed dispersal as a means of reproduction, many plants would quickly die out. Because plants lack any sort of mobility and remain in the same spot for their entire lives, they rely on seed dispersal to transport their offspring throughout the environment. This can be accomplished either collectively or individually; in any case as seeds ultimately abdicate their movement, they are at the mercy of environmental factors. Thus, seed dispersal strategies are characterized by robustness, adaptability, intelligence (both behavioral and morphological), and mass and energy efficiency (including the ability to utilize environmental sources of energy available): all qualities that advanced engineering systems aim at in general, and in particular those that need to enable complex endeavors such as space exploration. Plants evolved and adapted their strategy according to their environment, and taken together, they enclose many desirable characteristics that a space mission needs to have. Understanding in detail how plants control the development of seeds, fabricate structural components for their dispersal, build molecular machineries to keep seeds dormant up to the right moment and monitor the environment to release them at the right time could provide several solutions impacting current space mission design practices. It can lead to miniaturization, higher integration and packing efficiency, energy efficiency and higher autonomy and robustness. Consequently, there would appear to be good reasons for considering biomimetic solutions from plant kingdom when designing space missions, especially to other celestial bodies, where solid and liquid surfaces, atmosphere, etc constitute and are obviously parallel with the terrestrial environment where plants evolved. In this paper, we review the current state of biomimetics on seed dispersal to improve space mission design. PMID:23648867

Pandolfi, Camilla; Izzo, Dario

2013-05-07

104

PROPOSAL FOR AN INTEGRATED EUROPEAN SPACE EXPLORATION STRATEGY  

Microsoft Academic Search

Recently, in his vision for space exploration, US president Bush announced to extend human presence across the solar system, starting with a human return to the Moon as early as 2015 in preparation for hu- man exploration of Mars and other destinations. In Europe, an exploration program, termed AURORA, was established by ESA in 2001 - funded on a voluntary

Wolfgang Seboldt; Hans-Joachim Blome; Bernd Dachwald; Lutz Richter

105

Shielding Strategies for Human Space Exploration  

Microsoft Academic Search

The shield effectiveness of lunar regolith is compared with possible prefabricated shield materials from Earth,including commercially used shield materials in nuclear facilities. Several of the fabricated materials categorized asneutron absorbers and moderators exhibit favorable characteristics for space radiation protection. Although thiseffort is not intended to be a definitive trade study for specific shielding recommendations, attention is given toseveral factors that

J. W. Wilson; J. Miller; A. Konradi; F. A. Cucinotta

1997-01-01

106

The political sustainability of space exploration  

Microsoft Academic Search

The swiftly changing policy environment introduces significant uncertainty into the design of technical systems that rely on public resources. Politics necessarily impacts technical design as requirements change to suit different needs. Simple game-theoretic models may be used to provide insights into resource allocation dynamics between the National Aeronautics and Space Administration (NASA) and the US Congress. This paper utilizes game

David A. Broniatowski; Annalisa L. Weigel

2008-01-01

107

Indian Space Science and Exploration Missions  

Microsoft Academic Search

In earlier years, Indian scientists carried out studies of ionosphere and cosmic rays phenomena primarily using ground based radio techniques and balloon borne detectors. With the advent of the space era, parallel efforts in the indigenous design and development of different sounding rockets for electrojet and x-ray astronomy related research, satellite launch vehicles and satellites were undertaken. While these developments

S. C. Chakravarty

2004-01-01

108

Space Exploration and the Benefits to Mankind  

SciTech Connect

Paper presented at the 41st Congress of the International Astronautical Federation in Dresden, GDR in October 1990. This paper analyzes the past challenges of the space program's multi-national cooperative agreements and examines the challenges of the future as we quickly become a global society. Cross Reference ESD-T1.

Moser, T.L.; Freitag, R.; Schneider, W.C.

1990-10-01

109

Tracking and Data Acquisition for Space Exploration  

Microsoft Academic Search

The tracking and data acquisition systems provide the key link between the remote spacecraft and the scientific experimenter on the ground. The operation of the space experiment takes place through the links of command, telemetry and tracking. The evolution from the early very simple spacecraft missions toward more complex and sophisticated missions has been paralleled by a similar evolution in

Robert J. Coates

1969-01-01

110

Tracking and data acquisition for space exploration  

Microsoft Academic Search

The tracking and data acquisition systems provide the key link between the remote spacecraft and the scientific experimenter on the ground. The operation of the space experiment takes place through the links of command, telemetry and tracking. The evolution from the early very simple spacecraft missions toward more complex and sophisticated missions has been paralleled by a similar evolution in

Robert J. Coates

1969-01-01

111

Exploring Aeronautics and Space Technology. Teacher Edition.  

ERIC Educational Resources Information Center

|This curriculum guide contains six units of instruction for an introduction to the technology systems in the National Aeronautics and Space Administration (NASA). Designed to be used either as a stand-alone publication or to be infused into the instruction and activities of an existing technology education program, this publication describes the…

Buck, Sue; And Others

112

INNOVATIVE EXPLORER MISSION TO INTERSTELLAR SPACE  

Microsoft Academic Search

A mission to interstellar space has been under discussion for over 25 years. Many fundamental scientific questions about the nature of the surrounding galactic medium and its interaction with the solar system can only be answered by in situ measurements that such a mission would provide. The technical difficulties and budgetary and programmatic realities have prevented implementation of previous studies

Mike Gruntman; Ralph L. McNutt; Robert E. Gold; Stamatios M. Krimigis; Edmond C. Roelof; James C. Leary; George Gloeckler; Patrick L. Koehn; William S. Kurth; Steve R. Oleson

113

Explorations in Context Space: Words, Sentences, Discourse.  

ERIC Educational Resources Information Center

Describes a computational model of high-dimensional context space: the Hyperspace Analog to Language (HAL). Shows that HAL provides sufficient information to make semantic, grammatical, and abstract distinctions. Demonstrates the cognitive compatibility of the representations with human processing; and introduces a new methodology that extracts…

Burgess, Curt; Livesay, Kay; Lund, Kevin

1998-01-01

114

Design Space Exploration for The Beamformer System  

Microsoft Academic Search

We present a design exploration strategy for the beamformer system, an exampleof a typical DSP system. In order to do so, we first define a parameterizeddesign template for the beamformer and for a FIR filter, since the filteringoperation is a part of the overall beamformer system. We then discuss someapproaches for varying the design parameters for the filter and the

Daniel D. Gajski; Smita Bakshi

1993-01-01

115

Design space exploration with A Stream Compiler  

Microsoft Academic Search

We consider speeding up general-purpose applications with hardware accelerators. Traditionally hardware accelerators are tediously hand-crafted to achieve top performance ASC (A Stream Complier) simplifies exploration of hardware accelerators by transforming the hardware design task into a software design process using only 'gcc' and 'make' to obtain a hardware netlist. ASC enables programmers to customize hardware accelarators at three levels of

Oskar Mencer; David J. Pearce; Lee W. Howes; Wayne Luk

2003-01-01

116

Odyssey: Principles for enduring space exploration  

Microsoft Academic Search

As the USA, Europe and other nations embark on a new voyage of exploration to the Moon, Mars and beyond, they should lay the foundations and establish precedents that invite a host of participants and followers. We argue that international cooperation, driven by foreign-policy and cost-sharing considerations, has taken a prominent role but must be pragmatically and flexibly balanced with

Randall R. Correll; Nicolas Peter

2005-01-01

117

Fostering links between environmental and space exploration: the Earth and Space Foundation  

Microsoft Academic Search

The links between Earth and space exploration occur across a broad spectrum, from the use of satellite technology to support environmental monitoring and habitat protection to the study of extreme environments on Earth to prepare for the exploration of other planets. Taking the view that Earth and space exploration are part of a mutually beneficial continuum is in contrast to

Charles Cockell; Don White; Douglas Messier; M. Dale Stokes

2002-01-01

118

Fostering links between environmental and space exploration: the Earth and Space Foundation  

Microsoft Academic Search

The links between Earth and space exploration occur across a broad spectrum, from the use of satellite technology to support environmental monitoring and habitat protection to the study of extreme environments on Earth to prepare for the exploration of other planets. Taking the view that Earth and space exploration are part of a mutually beneficial continuum is in contrast to

Charles Cockella; Don Whitec; Douglas Messierd; M. Dale Stokese

119

Deep space flight of Hayabusa asteroid explorer  

NASA Astrophysics Data System (ADS)

The Hayabusa spacecraft rendezvoused with the asteroid Itokawa in 2005 after the powered flight in the deep space by the ?10 cathode-less electron cyclotron resonance ion engines. Though the spacecraft was seriously damaged after the successful soft-landing and lift-off, the xenon cold gas jets from the ion engines rescued it. New attitude stabilization method using a single reaction wheel, the ion beam jets, and the photon pressure was established and enabled the homeward journey from April 2007 aiming the Earth return on 2010. The total accumulated operational time of the ion engines reaches 31,400 hours at the end of 2007. One of four thrusters achieved 13,400-hour space operation.

Kuninaka, Hitoshi; Kawaguchi, Jun'ichiro

2008-05-01

120

Nuclear technology and the space exploration missions  

SciTech Connect

The strategy for a major exploration initiative leading to permanent human presence beyond earth orbit is still being developed; however enough is known to begin defining the role of nuclear technologies. Three broad areas are discussed: low power (less than 10 kWe) rover/vehicle power systems; integrated, evolutionary base power systems (25 to 100 kW) and nuclear energy for electric propulsion (2 to 100 MWe); and direct thermal propulsion (1000s MW). A phased, evolutionary approach is described for both the moon and Mars, and the benefits of nuclear technologies relative to solar and their integration are described.

Brandhorst, H.W.; Sovie, R.J.

1990-01-01

121

Space and Surface Power for the Space Exploration Initiative: Results from Project Outreach.  

National Technical Information Service (NTIS)

The analysis and evaluations of the Space and Surface Power panel, one of eight panels created by RAND to screen and analyze submissions to the Space Exploration Initiative (SEI) Outreach Program, is documented. In addition to managing and evaluating the ...

C. Shipbaugh K. Solomon D. Gonzales M. Juncosa T. Bauer

1991-01-01

122

Extreme Requirements for Robotics in Space Exploration and Utilization  

Microsoft Academic Search

This article intends to list and analyze the class of specific requirements implied in the R&D work for robotic systems suited for space exploration and utilization. The requirements can be called as \\

A. K. Bejczy

2006-01-01

123

Hardware\\/Software Design Space Exploration for a Reconfigurable Processor  

Microsoft Academic Search

This paper describes an approach to hardware\\/software design space exploration for reconfigurable processors. The existing compiler tool-chain, because of the user-definable instructions, needs to be extended in order to offer developers an easy way to explore design space. Such extension often is not easy to use for developer that have only a software background, thus ignoring reconfigurable architecture details or

Alberto La Rosa; Luciano Lavagno; Claudio Passerone

2003-01-01

124

School of Earth and Space Exploration at Arizona State University  

NSDL National Science Digital Library

The ASU School of Earth and Space Exploration (SESE) was formed in 2006 by merging previously separate academic programs in geoscience and planetary science, astronomy, and systems engineering. SESE is explicitly designed to enhance knowledge of Earth and the universe through innovative trans-disciplinary exploration, research, and teaching. Earth and space science education research, teacher preparation, and outreach are among the principal functions of SESE.

Exploration, School O.; University, Arizona S.

125

Noradrenergic modulation of space exploration in visual neglect.  

PubMed

Visual neglect after stroke is often associated with a failure to explore contralesional space. Here, we show that guanfacine, a noradrenergic agonist that modulates dorsolateral prefrontal cortex, improves leftward space exploration in selected right-hemisphere patients with neglect. The positive effects of guanfacine were associated with extended ability to maintain attention on task. The results suggest that neuropharmacological targeting of intact frontal areas might be one way to enhance cognitive function after damage to posterior brain regions in selected individuals. PMID:16261567

Malhotra, Paresh A; Parton, Andrew D; Greenwood, Richard; Husain, Masud

2006-01-01

126

A solution methodology for exact design space exploration in a three-dimensional design space  

Microsoft Academic Search

This paper describes an exact solution methodology, implemented in Rensselaer's Voyager design space exploration system, for solving the scheduling problem in a three-dimensional (3-D) design space: the usual two-dimensional (2-D) design space (which trades off area and schedule length), plus a third dimension representing clock length. Unlike design space exploration methodologies which rely on bounds or estimates, this methodology is

Samit Chaudhuri; S. A. Blthye; Robert A. Walker

1997-01-01

127

Will the US remain the real leader of human space exploration? A comparative assessment of space exploration policies  

NASA Astrophysics Data System (ADS)

Human space exploration is at a turning point which should find its outcome during the coming decade: Shuttle is being retired, ISS will be exploited up to 2020 minimum. Today the US exploration plans are sucked down into political battles, Europe and Japan are nearly nowhere, Russia's plans are hazy, China's ambitions are clear and implemented, and new actors such as India are raising their profile. In this uncertain environment, the question might be asked: who will be the leaders of human space exploration in 10-15 years from now?The assumption of the paper is that some key enabling factors are essential for a country to play a substantial role in human space exploration:There should be some long term political stability or continuityThe domain should be high in the political agenda of the country's decision makersThe global budget environment of the country should be positiveSpace should not be too much competed by other budget “catchers”The paper will propose a tentative comparison of the main space faring countries plans, ambitions and likely positioning, for human space exploration. Starting from the today situation and recent past evolutions, we will try to establish future trends for these key factors, and through that to identify which countries might be the most dynamically engaged in human space exploration.

Grimard, Max

2012-06-01

128

C-QWIPs for space exploration  

Microsoft Academic Search

We have extended our investigation of corrugated quantum well infrared photodetector focal plane arrays (C-QWIP FPAs) into the far infrared regime. Specifically, we are developing the detectors for the thermal infrared sensor (TIRS) used in the NASA Landsat Data Continuity Mission. This mission requires infrared detection cutoff at 12.5?m and FPAs operated at ?43K. To maintain a low dark current

K. K. Choi; M. D. Jhabvala; D. P. Forrai; J. Sun; D. Endres

2011-01-01

129

Mothers in the making? Exploring liminality in cyber\\/space  

Microsoft Academic Search

This paper makes a case for cyberspace and geographical space coexisting simultaneously as an interconnected dyadic cyber\\/space combining the virtually real and the actually real. Based on empirical evidence from a study examining the role of the Internet in the life of new mothers, we investigate the simultaneity of online\\/onsite experiences through an exploration of cyberspace as a performative liminal

Clare Madge; Henrietta O'Connor

2005-01-01

130

TriMedia CPU64 Design Space Exploration  

Microsoft Academic Search

Within Philips Research Labs, we are investigating the 64- bit VLIW core for future TriMedia processors. We have per- formed an extensive Design Space Exploration (DSE) on this core using quantitative analysis, using a benchmark suite of applications which are representative for multi- media processing. We have explored, among others, the configurations of the different functional units (FUs) of the

Gerben J. Hekstra; G. D. La Hei; Peter Bingley; Frans Sijstermans

1999-01-01

131

U.S. Vision for Space Exploration: Who Benefits?  

Microsoft Academic Search

In January 2004, President Bush announced a new vision for NASA, starting with a human return to the Moon by 2020 to be followed by human exploration of Mars and other destinations. The President's Moon-Mars initiative provides a compelling directive for the future of NASA, one that is at the next frontier in space exploration. However, it also presents substantial

Eric Barron

2005-01-01

132

Goals for space exploration based on stakeholder value network considerations  

Microsoft Academic Search

We present a methodology that provides traceable analysis from stakeholders’ needs to prioritized goals for human space exploration. We first construct a network to represent the stakeholder environment of NASA’s human exploration efforts, then assess the intensity of these stakeholder needs, and build a numerical model to represent the flow of value in the network. The underlying principle is that

Bruce G. Cameron; Theodore Seher; Edward F. Crawley

2011-01-01

133

Power system requirements and selection for the Space Exploration Initiative  

NASA Astrophysics Data System (ADS)

The role of the NASA Synthesis Group in four significantly different architectures for the SEI program is discussed. These architectures are: (1) Mars Exploration, (2) Science Emphasis for the moon and Mars, (3) the moon to stay and Mars exploration, and (4) Space Resource Utilization. The power requirements and power system options are examined for these architectures.

Biringer, Kent L.; Bartine, Dave E.; Buden, David; Foreman, Joe; Harrison, Steve

1991-09-01

134

Concept Space Comparisons: Explorations with Five Health Domains  

PubMed Central

This paper explores methods to compare concept spaces derived from different discourses in a common health domain. The concept spaces are generated from the research literature and from message board discussions on the Internet. We explore a number of methods for comparing and contrasting concept space pairs. We experiment with five select health domains in this exploratory research: Autism, AIDS, Fibromyalgia, Irritable Bowel Syndrome and Multiple Sclerosis. The paper concludes with a discussion about the potential of our methods. Future work on refinements to our techniques is also outlined.

Zhou, Li; Srinivasan, Padmini

2005-01-01

135

Future perspectives on space exploration and options for Europe  

NASA Astrophysics Data System (ADS)

This paper is intended as a first step in paving the way towards further reflection on the future position and role of Europe in space exploration. It provides a contribution to strategic policy-making at the European level by highlighting some of the variables influencing the evolution of the international system in which Europe will have to operate until 2025, as well as plans and ambitions for major and emerging space actors. Space exploration is an emblematic domain of space activities where traditionally only established space powers have been active. But, following the evolution of the space context new actors are increasingly interested to be involved in those activities principally for international prestige reasons. An increasing number of actors are thus taking on ambitious plans with orbiters, robotic landers, sample return and human exploration missions. However, complementing national endeavours international cooperation has over the years become a central element of the strategy of most countries involved in space exploration since it is a demanding effort. Human and robotic space exploration endeavours are embedded in a complex system of different "earthly" factors. These determinants will influence the decisions taken today for programmes which will be carried out in the future. It is therefore indispensable to be prepared for the on-going changes in the world which might affect the planning and the aspirations of space-faring countries. Europe's long-term exploration programme thus cannot be decoupled from emerging global trends and the plans of other major space-faring actors who shape the global environment for space exploration. The development of Europe into a fully-fledged actor in space exploration plans requires consequently a shared assessment of the future challenges, threats and opportunities with which it will be confronted with. Europe will have to take into account the evolution of key structural factors affecting changes over the two decades to come (demography, economy, environment, energy etc.) and the development of future potential partners to derive the best options for leading and anticipate rather than following and enduring change.

Peter, N.

2009-04-01

136

The Solar System in the Age of Space Exploration  

NASA Astrophysics Data System (ADS)

We are celebrating the 50th anniversary of the launch of Sputnik, which began the space age. Though the manned exploration of the solar system has been limited to the Moon, in NASA's Apollo Program that ended over 35 years ago, robotic exploration of the solar system continues to be very successful. This paper explores the latest space mission and other observations of each planet and of each type of solar-system object, including dwarf planets, asteroids, and comets, as well as the sun.

Pasachoff, Jay M.

2011-06-01

137

Science Goals for Human Explorers in Deep Space  

NASA Astrophysics Data System (ADS)

At the turn of the Century there have been several reports by the U.S. National Academy of Sciences that recommend scientific goals and set priorities for robotic space exploration by NASA in the first decade of the 21st Century. These are the so-called "Decadal Reports" the first of which appeared for Astronomy and Astrophysics in 1998, and the second two issued this year for Solar System Exploration and for Solar and Space Physics. These reports contain the kernel for extrapolating science goals into the following decade and identifying which are most appropriate for implementation by human explorers. Additionally, there are studies by NASA, ESA and professional organizations which explore visions for the next steps in exploring deep space including both robotic and human elements--an internal study by NASA, some of which was presented at the Space 2001 Conference, a Space Policy Summit sponsored by the AIAA for this conference, a study by the IAA reported at this conference and to be completed in the next year, and the Aurora study by ESA. The science goals for human exploration beyond Earth orbit for the next 10-20 years that emerge from these studies will be reported.

Huntress, W. T.

2002-01-01

138

Human life support for advanced space exploration.  

PubMed

The requirements for a human life support system for long-duration space missions are reviewed. The system design of a controlled ecological life support system is briefly described, followed by a more detailed account of the study of the conceptual design of a Lunar Based CELSS. The latter is to provide a safe, reliable, recycling lunar base life support system based on a hybrid physicochemical/biological representative technology. The most important conclusion reached by this study is that implementation of a completely recycling CELSS approach for a lunar base is not only feasible, but eminently practical. On a cumulative launch mass basis, a 4-person Lunar Base CELSS would pay for itself in approximately 2.6 years relative to a physicochemical air/water recycling system with resupply of food from the Earth. For crew sizes of 30 and 100, the breakeven point would come even sooner, after 2.1 and 1.7 years, respectively, due to the increased mass savings that can be realized with the larger plant growth units. Two other conclusions are particularly important with regard to the orientation of future research and technology development. First, the mass estimates of the Lunar Base CELSS indicate that a primary design objective in implementing this kind of system must be to minimized the mass and power requirement of the food production plant growth units, which greatly surpass those of the other air and water recycling systems. Consequently, substantial research must be directed at identifying ways to produce food more efficiently. On the other hand, detailed studies to identify the best technology options for the other subsystems should not be expected to produce dramatic reductions in either mass or power requirement of a Lunar Base CELSS. The most crucial evaluation criterion must, therefore, be the capability for functional integration of these technologies into the ultimate design of the system. Secondly, this study illustrates that existing or near-term technologies are adequate to implement a Lunar Base CELSS. There are no apparent "show-stoppers" which require the development of new technologies. However, there are several areas in which new materials and technologies could be used for a more efficient implementation of the system, e.g., by decreasing mass or power requirement and increasing recycling efficiency. These areas must be further addressed through research and development. Finally, although this study focused on the development of a Lunar Base CELSS, the same technologies and a nearly identical design would be appropriate for a Mars base. Actually, except for the distance of transportation, the implementation of a CELSS on Mars would even be easier than it would be on the Moon. The presence of atmospheric CO2 on Mars, although in low concentration, coupled with the fact that the day/night cycle on Mars is very similar to that on Earth, makes the use of light-weight, greenhouse-like structures for growing food plants even more feasible than on the Moon. There are some environmental problems, which would have to be dealt with, like dust storms and the large amount of the ultraviolet radiation incident on the planet's surface. However, the materials and methods are largely available today to develop such a life support system for a Mars base. PMID:9048141

Schwartzkopf, S H

1997-01-01

139

Evaluation of dual multi-mission space exploration vehicle operations during simulated planetary surface exploration  

NASA Astrophysics Data System (ADS)

A pair of small pressurized rovers (multi-mission space exploration vehicles, or MMSEVs) is at the center of the Global Point-of-Departure architecture for future human lunar exploration. Simultaneous operation of multiple crewed surface assets should maximize productive crew time, minimize overhead, and preserve contingency return paths.

Abercromby, Andrew F. J.; Gernhardt, Michael L.; Jadwick, Jennifer

2013-10-01

140

Development of a biochip dedicated to planetary exploration. First step: resistance studies to space conditions  

NASA Astrophysics Data System (ADS)

For upcoming exploration missions, space agencies advocate the development of a new promising technique to search for traces of extent or extinct life: the biochip use. As space is a hazardous environment, a main concern relies on the resistance of this device to a panel of harsh constraints. Within the framework of the BiOMAS (Biochip for Organic Matter Analysis in Space) project, our team is currently developing a biochip especially designed for planetary exploration. We present here the methodology adopted and the beginning experiments to select the best constituents, to determine resistance levels and to define well-adapted protection for the biochip.

Le Postollec, A.; Dobrijevic, M.; Incerti, S.; Moretto, Ph.; Seznec, H.; Desorgher, L.; Santin, G.; Nieminen, P.; Dartnell, L.; Vandenabeele-Trambouze, O.; Coussot, G.

2007-07-01

141

Science on the Moon: The Wailing Wall of Space Exploration  

NASA Astrophysics Data System (ADS)

Science on and from the Moon has important implications for expanding human knowledge and understanding, a prospect for the 21st Century that has been under discussion for at least the past 25 years [1-3]. That having been said, however, there remain many issues of international versus national priorities, strategy, economy, and politics that come into play. The result is a very complex form of human behavior where science and exploration take center stage, but many other important human options are sacrificed. To renew this dialogue about the Moon, it seems we are already rushing pell-mell into it as has been done in the past. The U.S., Japan, China, India, and Russia either have sent or plan to send satellites and robotic landers there at this time. What does a return to the Moon mean, why are we doing this now, who should pay for it, and how? The only semblance of such a human enterprise seems to be the LHC currently coming online at CERN. Can it be used as a model of international collaboration rather than a sports or military event focused on national competition? Who decides and what is the human sacrifice? There are compelling arguments for establishing science on the Moon as one of the primary goals for returning to the Moon and venturing beyond. A number of science endeavors will be summarized, beyond lunar and planetary science per se. These include fundamental physics experiments that are background-limited by the Earth's magnetic dipole moment and noise produced by its atmosphere and seismic interior. The Moon is an excellent platform for some forms of astronomy. Other candidate Moon-based experiments vary from neutrino and gravitational wave astronomy, particle astrophysics, and cosmic-ray calorimeters, to space physics and fundamental physics such as proton decay. The list goes on and includes placing humans in a hostile environment to study the long-term effects of space weather. The list is long, and even newer ideas will come from this COSPAR conference. However, whatever the list the issue of cooperation and binding collaboration remains. As observers of Moon and other space enterprises, we all know that a room full of 60 scientists will not agree on much of anything and there will probably be 60! pleas for more funding. People have special interests and little common sense (e.g., conflict between NSF- and NASA-funding roadmaps). Scientists are no exception. Nevertheless, CERN has done it on Earth! Can we do the same on the Moon? Some of the present generation of proposals for science from and on the Moon, plus new ones, will witness a place in space exploration's future. It is clear, however, that the world has not thought this through adequately, except for talk about an international space federation - whatever that is. An outpost on the Moon with humans permanently living there much like Antarctica on Earth may be in our future. However, such planning is our collective international responsibility and not that of special-interest investigators from individual nations - unless they intend to pay for it. [1] Mendell W. W. (1985) Lunar Bases and Space Activities of the 21st Century, Lunar and Planetary Institute, Houston. [2] Potter A. E. and Wilson T. L. (1990) Physics and Astrophysics from a Lunar Base, AIP Conf. Proc. 202, American Institute of Physics, New York. [3] Mumma M. J. and Smith H. J. (1990) Astrophysics from the Moon, AIP Conf. Proc. 207, American Institute of Physics, New York.

Wilson, Thomas

142

A Sweep-Line Method for State Space Exploration  

Microsoft Academic Search

We present a state space exploration method for on-the-fly verification. The method is aimed at systems for which it is possible to define a measure of progress based on the states of the system. The measure of progress makes it possible to delete certain states on-the-fly during state space generation, since these states can never be reached again. This in

Søren Christensen; Lars Michael Kristensen; Thomas Mailund

2001-01-01

143

Multi-objective design space exploration using genetic algorithms  

Microsoft Academic Search

In this work, we provide a technique for efficiently exploring a parameterized system-on-a-chip (SoC) architecture to find all Pareto-optimal configurations in a multi-objective design space. Globally, our approach uses a parameter dependency model of our target parameterized SoC architecture to extensively prune non-optimal sub-spaces. Locally, our approach applies Genetic Algorithms (GAs) to discover Pareto-optimal configurations within the remaining design points.

Maurizio Palesi; Tony Givargis

2002-01-01

144

Partial-Order Reduction in Symbolic State-Space Exploration  

Microsoft Academic Search

Abstract. State space explosion is a fundamental,obstacle in formal verification of de- signs and protocols. Several techniques for combating,this problem have emerged,in the past few years, among which two are significant: partial-ord er reductions and symbolic state space search. In asynchronous systems, interleaving s of independent concurrent events are equivalent, and only a representative interleav ing needs to be explored

Rajeev Alur; Robert K. Brayton; Thomas A. Henzinger; Shaz Qadeer; Sriram K. Rajamani

2001-01-01

145

Efficiently exploring architectural design spaces via predictive modeling  

Microsoft Academic Search

Architects use cycle-by-cycle simulation to evaluate design choices and understand tradeoffs and interactions among design param- eters. Efficiently exploring exponential-size design spaces with many interacting parameters remains an open problem: the sheer number of experiments renders detailed simulation intractable. We attack this problem via an automated approach that builds accurate, confident predictive design-space models. We simulate sampled points, using the

Engin Ipek; Sally A. Mckee; Rich Caruana; Bronis R. De Supinski; Martin Schulz

2006-01-01

146

Third SEI Technical Interchange: Proceedings. [Space Exploration Initiative  

SciTech Connect

Given here are the proceedings of the 3rd Space Exploration Initiative (SEI) Technical Interchange. Topics covered include the First Lunar Outpost (FLO), the Lunar Resource Mapper, lunar rovers, lunar habitat concepts, lunar shelter construction analysis, thermoelectric nuclear power systems for SEI, cryogenic storage, a space network for lunar communications, the moon as a solar power satellite, and off-the-shelf avionics for future SEI missions.

Not Available

1992-01-01

147

CMP design space exploration subject to physical constraints  

Microsoft Academic Search

This paper explores the multi-dimensional design space for chip multiprocessors, exploring the inter-related vari-ables of core count, pipeline depth, superscalar width, L2 cache size, and operating voltage and frequency, under various area and thermal constraints. The results show the importance of joint optimization. Thermal constraints dominate other physical constraints such as pin-bandwidth and power delivery, demonstrating the importance of con-sidering

Yingmin Li; Benjamin Lee; David Brooks; Zhigang Hu; Kevin Skadron

2006-01-01

148

CMP Design Space Exploration Subject to Physical Constraints  

Microsoft Academic Search

This paper explores the multi-dimensional design space for chip multiprocessors, exploring the inter-related vari- ables of core count, pipeline depth, superscalar width, L2 cache size, and operating voltage and frequency, under various area and thermal constraints. The results show the importance of joint optimization. Thermal constraints dominate other physical constraints such as pin-bandwidth and power delivery, demonstrating the importance of

Yingmin Li; Benjamin Lee; David Brooks; Zhigang Huy; Kevin Skadron

149

Space Storms, Ring Current and Space-Atmosphere Coupling  

Microsoft Academic Search

\\u000a Space storms are the prime complex processes of space weather. They interconnect, in a uniquely global manner, the Sun, the\\u000a interplanetary space, the terrestrial magnetosphere and atmosphere, and occasionally the surface of the Earth. Energy from\\u000a the Sun drives a continuous interaction of these distinct but coupled regions. The essential element of space storms in the\\u000a near-Earth space environment is

Ioannis A. Daglis

150

Document Explorer Visualizations of WWW Document and Term Spaces  

Microsoft Academic Search

Visualization is a promising technique for both enhancing users' perception of structure in the Internet and providing navigation facilities for its large information spaces. This paper describes an application of the Document Explorer to the visualization of WWW content structure. The system provides visualization, browsing, and query formulation mechanisms based on documents' semantic content. These mechanisms complement text and link

Richard H. Fowler; Wendy A. L. Fowler; Jorge L. Williams

1996-01-01

151

Functional abstraction driven design space exploration of heterogeneous programmable architectures  

Microsoft Academic Search

Rapid Design Space Exploration (DSE) of a programmable architecture is feasible using an automatic toolkit (compiler, simulator, assembler) generation methodology driven by an Architecture Description Language (ADL). While many contemporary ADLs can effectively capture one class of architecture, they are typically unable to capture a wide spectrum of processor and memory features present in DSP, VLIW, EPIC and Superscalar processors.

Prabhat Mishra; Nikil D. Dutt; Alexandru Nicolau

2001-01-01

152

Efficient search space exploration for HW-SW partitioning  

Microsoft Academic Search

Hardware\\/software (HW-SW) partitioning is a key problem in the codesign of embedded systems, studied extensively in the past. One major open challenge for traditional partitioning approaches -- as we move to more complex and heterogeneous SOCs -- is the lack of efficient exploration of the large space of possible HW\\/SW configurations, coupled with the inability to efficiently scale up with

Sudarshan Banerjee; Nikil D. Dutt

2004-01-01

153

Hardware\\/software partitioning with integrated hardware design space exploration  

Microsoft Academic Search

This paper presents an integrated approach to hardware software partitioning and hardware design space exploration. We propose a genetic algorithm which performs hardware software partitioning on a task graph while simultaneously contemplating various design alternatives for tasks mapped to hardware. We primarily deal with data dominated designs typically found in digital signal processing and image processing applications. A detailed description

Vinoo Srinivasan; Shankar Radhakrishnan; Ranga Vemuri

1998-01-01

154

Intelligent Systems Technologies for Human Space Exploration Mission Operations  

Microsoft Academic Search

Human space flight and exploration continues to be a key goal of the NASA, with an emphasis on utilizing new technologies to improve the effectiveness, efficiencies and safety associated with this endeavor, including the ground-based mission support. This search for improvement has led to cross- fertilization between the advanced software development community and the manned spaceflight operations community within NASA.

Ernest E. Smith; David J. Korsmeyer

2011-01-01

155

The practical value of health management in space exploration systems  

Microsoft Academic Search

There is a body of evidence, and a group of advocates, supporting the need for integrated system health management for space exploration systems. The advocates include operators responsible for complex and inherently risky decisions, and the technologists working in the domain of health management and looking for application for their products. Others in the decision loops take the view that

William Kahle; Jim Miller

2005-01-01

156

SPACE TRANSPORTATION NETWORK MODEL FOR RAPID LUNAR ARCHITECTURES EXPLORATION  

Microsoft Academic Search

The challenge of space exploration is to do technologically and cost efficient short and long-term missions. With uncertainty in funding, political and public support, mission design and planning needs to forward sustainable architecture decisions. We develop a rapid evaluation tool for lunar architectures, which allows analysis of many mission and technological options simultaneously. This paper explains the modeling approach, and

Gergana Bounova; Olivier de Weck

157

Skateboarders exploring urban public space: Ollies, obstacles and conflicts  

Microsoft Academic Search

This paper reports on an explorative study about skateboarding practices in Amsterdam. One indoor spot and nine street locations for skateboarding were observed and over thirty skaters were interviewed. The research questions concern the identity of the people involved, the group interactions, and the use of urban space and routes. The majority of the observed skateboarders are male middle-class youngsters.

Lia Karsten; Eva Pel

2000-01-01

158

The excitement and challenges of space and earth exploration  

Microsoft Academic Search

Over the last 50 years, the use of space platform to explore and observe our planet and the universe surrounding us has advanced in leaps and bounds. As of today there are more than hundred scientific Spacecraft monitoring all aspects of our planet environment and studying the planets in our solar system. In this talk I will discuss the advances

Charles Etachi

2009-01-01

159

Space: exploration-exploitation and the role of man.  

PubMed

The early years of space activity have emphasized a crew role similar to that of the test pilot or the crew of a high performance aircraft; even the Apollo lunar exploration missions were dominated by the task of getting to and from the moon. Skylab was a prototype space station and began to indicate the range of other functional roles man will play in space. The operation of the Space Shuttle has the elements of the operation of any other high performance flight vehicle during launch and landing; but in its on-orbit operations, it is often a surrogate space station, developing techniques and demonstrating the role of a future space station in various functions. In future space systems, the role of the crew will encompass all of the activities pursued in research laboratories, manufacturing facilities, maintenance shops, and construction sites. The challenge will be to design the tasks and the tools so that the full benefit of the opportunities offered by performing these functions in space can be attained. PMID:3778404

Loftus, J P

1986-10-01

160

Space and surface power for the space exploration initiative: Results from project outreach  

Microsoft Academic Search

The analysis and evaluations of the Space and Surface Power panel, one of eight panels created by RAND to screen and analyze submissions to the Space Exploration Initiative (SEI) Outreach Program, is documented. In addition to managing and evaluating the responses, or submissions, to this public outreach program, RAND conducted its own analysis and evaluation relevent to SEI mission concepts,

C. Shipbaugh; K. Solomon; D. Gonzales; M. Juncosa; T. Bauer; R. Salter

1991-01-01

161

NASA Utilization of the International Space Station and the Vision for Space Exploration.  

National Technical Information Service (NTIS)

Under U.S. President Bush's Vision for Space Exploration (January 14, 2004), NASA has refocused its utilization plans for the International Space Station (ISS). This use will now focus on: (1) the development of countermeasures that will protect crews fro...

J. A. Robinson D. A. Thomas

2006-01-01

162

NASA's In-Space Propulsion Technology Program: A Step Toward Interstellar Exploration  

NASA Astrophysics Data System (ADS)

NASA's In-Space Propulsion Technology Program is investing in technologies that have the potential to revolutionize the robotic exploration of deep space. For robotic exploration and science missions, increased efficiencies of future propulsion systems are critical to reduce overall life-cycle costs and, in some cases, enable missions previously considered impossible. Continued reliance on conventional chemical propulsion alone will not enable the robust exploration of deep space. The maximum theoretical efficiencies have almost been reached and are insufficient to meet needs for many ambitious science missions currently being considered. By developing the capability to support mid-term robotic mission needs, the program is laying the technological foundation for travel to nearby interstellar space. The In-Space Propulsion Technology Program's technology portfolio includes many advanced propulsion systems. From the next-generation ion propulsion systems operating in the 5-10 kW range, to solar sail propulsion, substantial advances in spacecraft propulsion performance are anticipated. Some of the most promising technologies for achieving these goals use the environment of space itself for energy and propulsion and are generically called “propellantless” because they do not require onboard fuel to achieve thrust. Propellantless propulsion technologies include scientific innovations such as solar sails and aerocapture. This paper will provide an overview of those propellantless and propellant-based advanced propulsion technologies that will most significantly advance our exploration of deep space.

Johnson, L.; James, B.; Baggett, R.; Montgomery, E. E., IV

163

The role of nuclear reactors in space exploration and development  

SciTech Connect

The United States has launched more than 20 radioisotopic thermoelectric generators (RTGs) into space over the past 30 yr but has launched only one nuclear reactor, and that was in 1965. Russia has launched more than 30 reactors. The RTGs use the heat of alpha decay of {sup 238}Pu for power and typically generate <1 kW of electricity. Apollo, Pioneer, Voyager, Viking, Galileo, Ulysses, and Cassini all used RTGs. Space reactors use the fission energy of {sup 235}U; typical designs are for 100 to 1000 kW of electricity. The only US space reactor launch (SNAP-10A) was a demonstration mission. One reason for the lack of space reactor use by the United States was the lack of space missions that required high power. But, another was the assumed negative publicity that would accompany a reactor launch. The net result is that all space reactor programs after 1970 were terminated before an operating space reactor could be developed, and they are now many years from recovering the ability to build them. Two major near-term needs for space reactors are the human exploration of Mars and advanced missions to and beyond the orbit of Jupiter. To help obtain public acceptance of space reactors, one must correct some of the misconceptions concerning space reactors and convey the following facts to the public and to decision makers: Space reactors are 1000 times smaller in power and size than a commercial power reactor. A space reactor at launch is only as radioactive as a pile of dirt 60 m (200 ft) across. A space reactor contains no plutonium at launch. It does not become significantly radioactive until it is turned on, and it will be engineered so that no launch accident can turn it on, even if that means fueling it after launch. The reactor will not be turned on until it is in a high stable orbit or even on an earth-escape trajectory for some missions. The benefits of space reactors are that they give humanity a stairway to the planets and perhaps the stars. They open a new frontier for their children and their grandchildren. They pave the way for all life on earth to move out into the solar system. At one time, humans built and flew space reactors; it is time to do so again.

Lipinski, R.J.

2000-07-01

164

Manned Space Exploration Can Provide Great Scientific Benefits  

Microsoft Academic Search

An AGU Council statement (NASA: Earth and space sciences at risk, available at http:\\/\\/ www.agu.org\\/sci_soc\\/policy\\/positions\\/ earthspace_risk.shtml) and an Eos editorial [Barron, 2005], addressing NASA's envisioned manned Moon-Mars initiative, implicitly assume a zero-sum situation between manned and unmanned space programs. They also imply that the NASA initiative will not contribute significantly to science but will ``impact on the current and future

S. Fred Singer

2005-01-01

165

Space debris, remarks on current legal issues  

Microsoft Academic Search

A legal definition of space debris must take into consideration its consequences on the legal status of the object. For the purpose of mitigation of space debris at the time of the launch, any object launched in outer pace will turn sooner or later into a space debris. For liability purposes, a definition of a \\

Armel Kerrest

2001-01-01

166

Space transportation systems, launch systems, and propulsion for the Space Exploration Initiative: Results from Project Outreach  

NASA Astrophysics Data System (ADS)

A number of transportation and propulsion options for Mars exploration missions are analyzed. As part of Project Outreach, RAND received and evaluated 350 submissions in the launch vehicle, space transportation, and propulsion areas. After screening submissions, aggregating those that proposed identical or nearly identical concepts, and eliminating from further consideration those that violated known physical princples, we had reduced the total number of viable submissions to 213. In order to avoid comparing such disparate things as launch vehicles and electric propulsion systems, six broad technical areas were selected to categorize the submissions: space transportation systems; earth-to-orbit (ETO) launch systems; chemical propulsion; nuclear propulsion; low-thrust propulsion; and other. To provide an appropriate background for analyzing the submissions, an extensive survey was made of the various technologies relevant to the six broad areas listed above. We discuss these technologies with the intent of providing the reader with an indication of the current state of the art, as well as the advances that might be expected within the next 10 to 20 years.

Garber, T.; Hiland, J.; Orletsky, D.; Augenstein, B.; Miller, M.

1991-12-01

167

Space debris, remarks on current legal issues  

NASA Astrophysics Data System (ADS)

A legal definition of space debris must take into consideration its consequences on the legal status of the object. For the purpose of mitigation of space debris at the time of the launch, any object launched in outer pace will turn sooner or later into a space debris. For liability purposes, a definition of a "space object " is more useful that the notion of "space debris". It must be sure that every space debris is considered as a space objet according to the liability convention. At the end and certainly a more difficult issue is the qualification of a space object as a space debris when it will be technically feasible to remove it. The question of the property of the debris or object should be important. States are responsible and liable for space debris. According to article VI and VII of the Outer Space Treaty, they must authorise and control any national space activity and make sure these activities will not be conducted against the law. In the case of an accident and excepting the use of nuclear power sources, the main problem lies on damage in outer space to other spacecraft. In that case, the victim must prove a fault. According with the lack of precise rules it should be difficult. It should be necessary to precise the law applicable to space debris. At the domestic level, rules must be taken to prevent space debris through an assessment of risk within the licensing process. At the international level, the principle of an obligation to mitigate debris should be clearly accepted. Some general rules should be useful to avoid breach of competition between commercial actors. The adoption of a clear and precise code of conduct should be of great help because it would determine the good launching States' behaviour and greatly helps the judge appreciating the proof of a fault in case of an accident.

Kerrest, Armel

2001-10-01

168

Parameter space discretization and exploration for conceptual design of Mars in-situ instruments  

NASA Astrophysics Data System (ADS)

New system design processes are changing the way space instrument conceptual designs are generated. Processes are developed for concurrent engineering, and optimizing instrument mass, cost, and volume. However, it is often the case that using these processes generates only point designs, or a fraction of possible design solutions within the parameter space. Parameter space includes design and performance spaces. Design space is the decomposition of a product design into tasks and options. Design parameters of interest constitute the performance space. Furthermore, although the point designs are valid solutions, there are often viable solutions that have not been considered, which may better solve the optimization problem. The hypothesis of this research is that designers exploring the parameter space will find solutions that may not have otherwise been considered. These previously unconsidered solutions may better optimize design parameters than the point designs found with other methods. Current design approaches are summarized, and a GENEration of Space Instrument Systems (GENESIS) parameter space discretization and exploration conceptual design process is described that expands on these approaches. GENESIS combines design approaches, parametric models, database tools, and intelligent agents in a unique manner to discretize and explore instrument parameter space. While generic enough to apply to wide ranges of problems, this research focuses on application to Mars in-situ instruments. In-situ instruments are those that take measurements in contact with or close proximity to the object being measured. These instruments are interesting because they are often under strict mass, cost, and volume constraints, and require unique design solutions to meet these constraints. An instrument design model built around existing Mars in-situ instruments supports GENESIS. Case studies of existing instruments are examined to answer the question, 'Where do existing Mars in-situ instrument designs lie within the parameter space?' The contribution of GENESIS is: (1) a Mars in-situ instrument design space model; (2) a process for generating design options and exploring the parameter space; and (3) exploring Mars in-situ instrument parameter space to characterize possible improvement of current design methods. GENESIS extends the state of the practice in design and aids designers in finding unexplored solutions.

Rademacher, Joel David

169

Communicating about space science and exploration: a two way street.  

NASA Astrophysics Data System (ADS)

The news from space enter the press rooms of the media in different ways: from institutional communication of the space agencies and research institutes and from cables from the press agencies. The media then selects at several decision points in time which news deserve a subject for print or broadcast This process frequently by-passes communication plans and can lead to confusion especially when the covered events do not correspond to the expectations or reveal surprising science data as for example in the case of the GIOTTO spacecraft encounter with comet Halley when the camera were pointing towards bright jets and the dark cometary nucleus was relegated to a corner of the image. Informal case studies in both recent manned space flight and planetary explorations missions will be presented with discussion seeds in order to be able to satisfy better the needs of the public and society in the future.

Muller, C.

170

Exploring the solution space of beaconing in VANETs  

Microsoft Academic Search

Vehicular networking is an enabling technology for intelligent transportation systems (ITS). Different types of vehicular traffic applications are currently being investigated. In this paper we briefly introduce the communication requirements of a cooperative adaptive cruise control (C-ACC) vehicular traffic efficiency application. Furthermore, we propose a channel busy time model to evaluate the solution space of a vehicular beaconing system designed

Eenennaam van Martijn; Wouter Klein Wolterink; Georgios Karagiannis; Geert Heijenk

2009-01-01

171

Opportunities for Space Science Education Using Current and Future Solar System Missions  

Microsoft Academic Search

The Education and Public Outreach (E\\/PO) office in The Johns Hopkins University Applied Physics Laboratory (APL) Space Department strives to excite and inspire the next generation of explorers by creating interactive education experiences. Since 1959, APL engineers and scientists have designed, built, and launched 61 spacecraft and over 150 instruments involved in space science. With the vast array of current

M. Matiella Novak; K. Beisser; L. Butler; D. Turney

2010-01-01

172

Crew roles and interactions in scientific space exploration  

NASA Astrophysics Data System (ADS)

Future piloted space exploration missions will focus more on science than engineering, a change which will challenge existing concepts for flight crew tasking and demand that participants with contrasting skills, values, and backgrounds learn to cooperate as equals. In terrestrial space flight analogs such as Desert Research And Technology Studies, engineers, pilots, and scientists can practice working together, taking advantage of the full breadth of all team members' training to produce harmonious, effective missions that maximize the time and attention the crew can devote to science. This paper presents, in a format usable as a reference by participants in the field, a successfully tested crew interaction model for such missions. The model builds upon the basic framework of a scientific field expedition by adding proven concepts from aviation and human space flight, including expeditionary behavior and cockpit resource management, cooperative crew tasking and adaptive leadership and followership, formal techniques for radio communication, and increased attention to operational considerations. The crews of future space flight analogs can use this model to demonstrate effective techniques, learn from each other, develop positive working relationships, and make their expeditions more successful, even if they have limited time to train together beforehand. This model can also inform the preparation and execution of actual future space flights.

Love, Stanley G.; Bleacher, Jacob E.

2013-10-01

173

Who Has Control: The Battle Between NASA and Congress Over the Space Shuttle to Vision for Space Exploration Transition  

Microsoft Academic Search

NASA rests under the Executive Branch as 2005 NASA Authorization Act and Aeronautics and Space act of 1958 fund NASA. NASA Authorization Acts and The Vision for Space Exploration (VSE) signed by President Bush in 2004 signaled the end of space explorations. Both Congress and the President are trying to assert control over future human space flight programs as Congress

Ashley Walker

2008-01-01

174

Exploring Current Arts Practice in Kindergartens and Preparatory Classrooms  

ERIC Educational Resources Information Center

|The arts are an important area of development for young children in their early years. By engaging with arts activities, young children are able to use their senses to explore the world. This paper reports on current arts practice in two kindergartens and two preparatory classrooms in Queensland, Australia. All sites are located in neighbouring…

Garvis, Susanne

2012-01-01

175

Introduction to the session on `Human Space Exploration'  

NASA Astrophysics Data System (ADS)

When Schiaparelli tried to interpret the surface of Mars as it appeared from his telescope, in particular with reference to the famous "channels", he formulated the hypothesis that they would have been the product of some intelligent Mars population. Today we know that this interpretation was not correct, but we would like to consider his idea as a sort of vision for a future when the humankind will export our civilization on Mars. In fact the objective of the international plans of "Space Exploration" is exactly to land the humans on Mars to start its colonization. Although a new approach is proposed which includes International Space Station, Moon, Asteroids, etc. in a sort of "flexible path" to look for "new worlds in the Solar System where is possible for the humankind to live and operate", it is confirmed that the "final destination" is Mars.

Messidoro, P.

176

Multi Robot Flocking Using Cooperative Control for Space Exploration  

NASA Astrophysics Data System (ADS)

This paper aims at achieving flocking behavior of multi robot systems for space explorations. Cooperative control of unmanned vehicles is used in the survey of unknown environments. Distributed control of multiple vehicles achieves the objective of exploration of wide areas while avoiding obstacles on their path. Gradient based algorithm is used to obtain necessary attractive/repulsive force to maintain flock. Similar force is used to avoid obstacles, which may be present in the environment. Velocity consensus algorithm helps in maintaining the necessary geometry of the flock. A target agent specifies the group behavior for the flock. Two wheel differential robot model with second order dynamics is considered here. Robot motion is assumed to be on plane terrain.

Chandran, Priya

2012-07-01

177

NASA utilization of the International Space Station and the Vision for Space Exploration  

NASA Astrophysics Data System (ADS)

In response to the US President's Vision for Space Exploration (January 14, 2004), NASA has revised its utilization plans for International Space Station (ISS) to focus on (1) research on astronaut health and the development of countermeasures that will protect our crews from the space environment during long-duration voyages, (2) ISS as a test bed for research and technology developments that will insure vehicle systems and operational practices are ready for future exploration missions, (3) developing and validating operational practices and procedures for long-duration space missions. In addition, NASA will continue a small amount of fundamental research in life and microgravity sciences. There have been significant research accomplishments that are important for achieving the Exploration Vision. Some of these have been formal research payloads, while others have come from research based on the operation of ISS. We will review a selection of these experiments and results, as well as outline some of ongoing and upcoming research. The ISS represents the only microgravity opportunity to perform on-orbit long-duration studies of human health and performance and technologies relevant for future long-duration missions planned during the next 25 years. Even as NASA focuses on developing the Orion spacecraft and return to the moon (2015 2020), research on and operation of the ISS is fundamental to the success of NASA's Exploration Vision.

Robinson, Julie A.; Thumm, Tracy L.; Thomas, Donald A.

2007-06-01

178

JEM on the Space Station: Current Status and Scientific Missions  

NASA Astrophysics Data System (ADS)

The international Space Station project is gradually in progress with various comments on yes or no. Space Activities Commission (a steering committee of all space activities in Japan) has reviewed current activities and proposed measures to promote space environment utilization for Japanese Experiment Module (JEM) on the Space Station. JEM has the exposed facility for space observations which will be available from 2001. In this report I describe a recent status of space activities for JEM briefly, and I would like to give a personal comment what kinds of high energy astrophysics missions should be considered or fit for the exposed facility for JEM.

Matsuoka, Masaru

179

U.S. Space Transportation Policy: Increased Military Role, Decreased International Cooperation, and Impacts to the Vision for Space Exploration  

Microsoft Academic Search

Approximately one year after the release of the Vision for Space Exploration (VSE), a United States Presidential Directive established the U. S. Space Transportation Policy on January 6, 2005. The policy supersedes aspects of previous Presidential Decision Directives pertaining to National Security Council Policy, National Space Policy, Defense Space Sector Guidelines, Commercial Space Guidelines, and others. The new U. S.

Corinne M. Contant-Jorgenson

180

National Space Biomedical Research Institute Education and Public Outreach Program: Education for the next generation of space explorers  

NASA Astrophysics Data System (ADS)

The National Space Biomedical Research Institute (NSBRI) Education and Public Outreach Program (EPOP) is supporting the National Aeronautics and Space Administration's (NASA) new vision for space exploration by educating and inspiring the next generation of students through a seamless pipeline of kindergarten through postdoctoral education programs. NSBRI EPOP initiatives are designed to train scientists and to communicate the significance of NSBRI science, as well as other space exploration science, to schools, families and lay audiences. The NSBRI EPOP team is comprised of eight main partners: Baylor College of Medicine (BCM), Binghamton University-State University of New York (BUSUNY), Colorado Consortium for Earth and Space Science Education (CCESSE), Massachusetts Institute of Technology (MIT), Morehouse School of Medicine (MSM), Mount Sinai School of Medicine (MSSM), Rice University and the University of Texas Medical Branch (RU-UTMB), and Texas A&M University (TAMU). The current kindergarten through undergraduate college (K-16) team, which was funded through an open national competition in 2004, consolidates the past 7 years of K-16 education activities and expands the team's outreach activities to more museums and science centers across the nation. NSBRI also recently expanded its education mission to include doctoral and postdoctoral level programs. This paper describes select K-16 EPOP activities and products developed over the past 7 years, and reports on new activities planned for the next 3 years. The paper also describes plans for a doctoral program and reports on 1st-year outcomes of the new postdoctoral program.

MacLeish, Marlene Y.; Thomson, William A.; Moreno, Nancy; Gannon, Patrick J.; Smith, Roland B.; Houston, Clifford W.; Coulter, Gary; Vogt, Gregory L.

2007-02-01

181

The Hematopoietic Stem Cell Therapy for Exploration of Deep Space  

NASA Astrophysics Data System (ADS)

Astronauts experience severe/invasive disorders caused by space environments. These include hematological and cardiac abnormalities, bone and muscle losses, immunodeficiency, neurological disorders and cancer. Exploiting the extraordinary plasticity of hematopoietic stem cells (HSCs), which differentiate not only to all types of blood cells, but also to various tissues, including muscle, bone, skin, liver, and neuronal cells, we advanced a hypothesis that some of the space-caused disorders might be amenable to hematopoietic stem cell therapy (HSCT) so as to maintain astronauts' homeostasis. If this were achievable, the HSCT could promote human exploration of deep space. Using mouse models of human anemia (?-thalassemia) and spaceflight (hindlimb suspension unloading system), we have obtained feasibility results of HSCT for space anemia, muscle loss, and immunodeficiency. For example, the ?-thalassemic mice were successfully transplanted with isologous HSCs, resulting in chimerism of hemoglobin species and alleviation of the hemoglobinopathy. In the case of HSCT for muscle loss, ?-galactosidase-marked HSCs, which were prepared from ?-galactosidase-transgenic mice, were detected by the X-gal wholemount staining procedure in the hindlimbs of unloaded mice following transplantation. Histochemical and physical analyses indicated structural contribution of HSCs to the muscle. To investigate HSCT for immunodeficiency, ?-galactosidase-transformed Escherichia coli was used as the reporter bacteria, and infected to control and the hindlimb suspended mice. Results of the X-gal stained tissues indicated that the HSCT could help eliminate the E. coli infection. In an effort to facilitate the HSCT in space, growth of HSCs has been optimized in the NASA Rotating Wall Vessel (RWV) culture systems, including Hydrodynamic Focusing Bioreactor (HFB).

Ohi, Seigo; Roach, Allana-Nicole; Ramsahai, Shweta; Kim, Bak C.; Fitzgerald, Wendy; Riley, Danny A.; Gonda, Steven R.

2004-02-01

182

Multi-Attribute Tradespace Exploration in Space System Design  

NASA Astrophysics Data System (ADS)

The complexity inherent in space systems necessarily requires intense expenditures of resources both human and monetary. The high level of ambiguity present in the early design phases of these systems causes long, highly iterative, and costly design cycles. This paper looks at incorporating decision theory methods into the early design processes to streamline communication of wants and needs among stakeholders and between levels of design. Communication channeled through formal utility interviews and analysis enables engineers to better understand the key drivers for the system and allows a more thorough exploration of the design tradespace. Multi-Attribute Tradespace Exploration (MATE), an evolving process incorporating decision theory into model and simulation- based design, has been applied to several space system case studies at MIT. Preliminary results indicate that this process can improve the quality of communication to more quickly resolve project ambiguity, and enable the engineer to discover better value designs for multiple stakeholders. MATE is also being integrated into a concurrent design environment to facilitate the transfer knowledge of important drivers into higher fidelity design phases. Formal utility theory provides a mechanism to bridge the language barrier between experts of different backgrounds and differing needs (e.g. scientists, engineers, managers, etc). MATE with concurrent design couples decision makers more closely to the design, and most importantly, maintains their presence between formal reviews.

Ross, A. M.; Hastings, D. E.

2002-01-01

183

Current Density and Space Potential in Plasmas.  

National Technical Information Service (NTIS)

A model that describes the operation of a magnetically confined, hollow cathode arc discharge has been developed. This model will be used to design a high current arc facility suitable for the development of plasma current density techniques using an ion ...

R. L. Hickok W. C. Jennings

1975-01-01

184

Exploration mission enhancements possible with power beaming. [Space Applications Power Beaming  

SciTech Connect

A key factor in the exploration and development of the space frontier is the availability of energy where and when it is needed. Currently all space satellites and platforms include self-contained power systems that supply the energy necessary to accomplish mission objectives. An alternative approach is to couple advanced high power system with energy beam transmitters and energy receivers to form an infrastructure of a space power utility where a central power system provides power to multiple users. Major space activities, such as low Earth orbit space commercialization and the colonization of the Moon or Mars, would benefit significantly from a central power generation and transmission system. This paper describes the power-beaming concept and system components as applied to space power generation and distribution in support of the Space Exploration Initiative. Beam-power scenarios are discussed including commonality of systems and hardware with cargo transport vehicles, power beaming from orbit to stationary and mobile users on the Lunar and Mars surfaces, and other surface applications. 6 refs.

Bamberger, J.A.; Coomes, E.P. (Pacific Northwest Lab., Richland, WA (USA)); Segna, D.R. (USDOE Richland Operations Office, WA (USA))

1990-10-01

185

Rule-based graph theory to enable exploration of the space system architecture design space  

NASA Astrophysics Data System (ADS)

The primary goal of this research is to improve upon system architecture modeling in order to enable the exploration of design space options. A system architecture is the description of the functional and physical allocation of elements and the relationships, interactions, and interfaces between those elements necessary to satisfy a set of constraints and requirements. The functional allocation defines the functions that each system (element) performs, and the physical allocation defines the systems required to meet those functions. Trading the functionality between systems leads to the architecture-level design space that is available to the system architect. The research presents a methodology that enables the modeling of complex space system architectures using a mathematical framework. To accomplish the goal of improved architecture modeling, the framework meets five goals: technical credibility, adaptability, flexibility, intuitiveness, and exhaustiveness. The framework is technically credible, in that it produces an accurate and complete representation of the system architecture under consideration. The framework is adaptable, in that it provides the ability to create user-specified locations, steady states, and functions. The framework is flexible, in that it allows the user to model system architectures to multiple destinations without changing the underlying framework. The framework is intuitive for user input while still creating a comprehensive mathematical representation that maintains the necessary information to completely model complex system architectures. Finally, the framework is exhaustive, in that it provides the ability to explore the entire system architecture design space. After an extensive search of the literature, graph theory presents a valuable mechanism for representing the flow of information or vehicles within a simple mathematical framework. Graph theory has been used in developing mathematical models of many transportation and network flow problems in the past, where nodes represent physical locations and edges represent the means by which information or vehicles travel between those locations. In space system architecting, expressing the physical locations (low-Earth orbit, low-lunar orbit, etc.) and steady states (interplanetary trajectory) as nodes and the different means of moving between the nodes (propulsive maneuvers, etc.) as edges formulates a mathematical representation of this design space. The selection of a given system architecture using graph theory entails defining the paths that the systems take through the space system architecture graph. A path through the graph is defined as a list of edges that are traversed, which in turn defines functions performed by the system. A structure to compactly represent this information is a matrix, called the system map, in which the column indices are associated with the systems that exist and row indices are associated with the edges, or functions, to which each system has access. Several contributions have been added to the state of the art in space system architecture analysis. The framework adds the capability to rapidly explore the design space without the need to limit trade options or the need for user interaction during the exploration process. The unique mathematical representation of a system architecture, through the use of the adjacency, incidence, and system map matrices, enables automated design space exploration using stochastic optimization processes. The innovative rule-based graph traversal algorithm ensures functional feasibility of each system architecture that is analyzed, and the automatic generation of the system hierarchy eliminates the need for the user to manually determine the relationships between systems during or before the design space exploration process. Finally, the rapid evaluation of system architectures for various mission types enables analysis of the system architecture design space for multiple destinations within an evolutionary exploration program. (Abstract shortened by UMI.).

Arney, Dale Curtis

186

Current and future air force space cryogenic technology development  

Microsoft Academic Search

Current space cryocooler developments have achieved performance and capability that have made the use of active refrigeration in space missions feasible. Several space flight demonstrations and operational programs have baselined and implemented active refrigeration to achieve mission goals. The application of cryocooler technology validates the progress achieved to enable improved mission capabilities and reliability and lifetime confidence in active refrigeration

B. J. Tomlinson; T. M. Davis; S. D. Hill; C. H. Bruninghaus

2002-01-01

187

Exploration of Stellarator Configuration Space with Global Search Methods  

SciTech Connect

An exploration of stellarator configuration space z for quasi-axisymmetric stellarator (QAS) designs is discussed, using methods which provide a more global view of that space. To this end, we have implemented a ''differential evolution'' (DE) search algorithm in an existing stellarator optimizer, which is much less prone to become trapped in local, suboptimal minima of the cost function chi than the local search methods used previously. This search algorithm is complemented by mapping studies of chi over z aimed at gaining insight into the results of the automated searches. We find that a wide range of the attractive QAS configurations previously found fall into a small number of classes, with each class corresponding to a basin of chi(z). We develop maps on which these earlier stellarators can be placed, the relations among them seen, and understanding gained into the physics differences between them. It is also found that, while still large, the region of z space containing practically realizable QAS configurations is much smaller than earlier supposed.

H.E. Mynick; N. Pomphrey; S. Ethier

2001-09-10

188

Nuclear safety for the space exploration initiative. Final report  

SciTech Connect

The results of a study to identify potential hazards arising from nuclear reactor power systems for use on the lunar and Martian surfaces, related safety issues, and resolutions of such issues by system design changes, operating procedures, and other means are presented. All safety aspects of nuclear reactor power systems from prelaunch ground handling to eventual disposal were examined consistent with the level of detail for SP-100 reactor design at the 1988 System Design Review and for launch vehicle and space transport vehicle designs and mission descriptions as defined in the 90-day Space Exploration Initiative (SEI) study. Information from previous aerospace nuclear safety studies was used where appropriate. Safety requirements for the SP-100 space nuclear reactor system were compiled. Mission profiles were defined with emphasis on activities after low earth orbit insertion. Accident scenarios were then qualitatively defined for each mission phase. Safety issues were identified for all mission phases with the aid of simplified event trees. Safety issue resolution approaches of the SP-100 program were compiled. Resolution approaches for those safety issues not covered by the SP-100 program were identified. Additionally, the resolution approaches of the SP-100 program were examined in light of the moon and Mars missions.

Dix, T.E.

1991-11-01

189

Space vector based current control schemes for voltage source inverters  

Microsoft Academic Search

Hysteresis controllers are very simple and fast schemes for current control in voltage source inverters. Their disadvantage, a much higher switching frequency compared to other PWM methods, can be distinctly reduced by applying space vector based two dimensional hysteresis controllers. Four different control schemes are discussed and compared: the conventional method with three independent phase current controllers and three space

D. Wuest; F. Jenni

1993-01-01

190

Private equity investments beyond Earth orbits: Can space exploration be the new frontier for private investments?  

Microsoft Academic Search

The year 2004 can be considered an important milestone for space activities. First, on January 14, 2004 President Bush announced a new vision for human and robotic space exploration named “A Renewed Spirit of Discovery”. This new space exploration policy called for “a sustained and affordable human and robotic program to explore the solar system and beyond” and seeks also

Jeph Mathurin; Nicolas Peter

2006-01-01

191

Affordable Mars Exploration Architectures: Applying Systems From The Commercial Development Of Space  

Microsoft Academic Search

This paper discusses the possibility of leveraging systems concepts and technologies needed for the commercial development of space in innovative, affordable human Mars exploration architectures. Since the late 1980s, various space agencies, industry and university groups have examined a diverse set of human Mars exploration options. In the United States, the 1989 Space Exploration Initiative (SEI) initiated a continuing series

John C. Mankins

2002-01-01

192

Algorithm and architecture-level design space exploration using hierarchical data flows  

Microsoft Academic Search

Incorporating algorithm and architecture level design space exploration in the early phases of the design process can have a dramatic impact on the area, speed, and power consumption of the resulting systems. This paper proposes a framework for supporting system-level design space exploration and discusses the three fundamental issues involved in effectively supporting such an early design space exploration: definition

Helvio P. Peixoto; Margarida F. Jacome

1997-01-01

193

Highly Survivable Avionics Systems for Long-Term Deep Space Exploration  

NASA Astrophysics Data System (ADS)

The design of highly survivable avionics systems for long-term (> 10 years) exploration of space is an essential technology for all current and future missions in the Outer Planets roadmap. Long-term exposure to extreme environmental conditions such as high radiation and low-temperatures make survivability in space a major challenge. Moreover, current and future missions are increasingly using commercial technology such as deep sub-micron (0.25 microns) fabrication processes with specialized circuit designs, commercial interfaces, processors, memory, and other commercial off the shelf components that were not designed for long-term survivability in space. Therefore, the design of highly reliable, and available systems for the exploration of Europa, Pluto and other destinations in deep-space require a comprehensive and fresh approach to this problem. This paper summarizes work in progress in three different areas: a framework for the design of highly reliable and highly available space avionics systems, distributed reliable computing architecture, and Guarded Software Upgrading (GSU) techniques for software upgrading during long-term missions. Additional information is contained in the original extended abstract.

Alkalai, L.; Chau, S.; Tai, A. T.

2001-01-01

194

Trade space evaluation of multi-mission architectures for the exploration of Europa  

NASA Astrophysics Data System (ADS)

Recent cuts to NASA's planetary exploration budget have precipitated a debate in the community on whether large flagship missions to planetary bodies in the outer solar system or sequences of smaller missions as part of a long-term exploration program would be more beneficial. The work presented explores the trade between these two approaches as applied to the exploration of Europa and concentrates on identifying combinations of flyby, orbiter and/or lander missions that achieve high value at a lower cost than the Jupiter Europa Orbiter (JEO) flagship mission concept. The effects of the value attributed to the four main science objectives for Europa, which can be broadly classified as investigating the ocean, ice-shell, composition and geology, are demonstrated. The current approach proposed to complete the ocean exploration objective is shown to have conflicting requirements with the other three objectives. For missions that fully address all the science objectives, such as JEO, the ocean goal is therefore found to be the main cost driver. Instrument combinations for low-cost flyby missions are also presented, and simple lander designs able to achieve a wide range of objectives at a low additional cost are identified. Finally, the current designs for the Europa Habitability Mission (EHM) are compared to others in the trade space, based on the prioritization given to the science goals for the exploration of Europa. The current EHM flyby mission (Clipper) is found to be highly promising in terms of providing very high potential science value at a low cost.

Alibay, F.; Strange, N. J.

195

Data Management in Planetary Exploration and Space Physics  

NASA Astrophysics Data System (ADS)

Planetary exploration and space physics approach data management in very different ways. In this talk we will compare the approaches in these two disciplines with emphasis on how each has dealt with the problems of locating and accessing distributed data. We also will outline the data management challenges each will face in the next decade. Sixteen years ago the NASA Solar System Exploration Division founded the Planetary Data System (PDS) to coordinate the data activities of planetary missions, provide the scientific community with access to planetary data and preserve the data from planetary missions for future analysis. PDS is organized into "nodes" by scientific sub-disciplines (Atmospheres, Geoscience, Plasma Interactions, Rings and Small Bodies) and experimental technique (Imaging and Radio Science). In addition the Navigation and Ancillary Information Facility (NAIF) addresses data issues involving navigation and instrument pointing. All planetary data from NASA missions are prepared to the same metadata standards that include a common data dictionary. Initially access to the data was by sub-discipline although within a sub-discipline the access was to all missions and instrument types. More recently planetary science has become more interdisciplinary and now PDS is moving toward a system that supports cross discipline access. Data are available either on online or on hard media (CDROM or DVD). In recent years space physics data access has been organized by missions. Some missions support data systems through which all of the data from the mission can be accessed while for others the data are available from individual principal investigator sites. In general the space physics missions support an open data policy and much of the data is available online. There are no discipline wide metadata standards. Different missions support different data dictionaries, schemas and interfaces. The data come in a variety of formats. In the near future both planetary science and space physics will be challenged with massive volumes of data from new missions (approximately 1015 bytes). In both disciplines the need for comparative research across missions or sub-disciplines is becoming more common. Both will have to support data structures that allow users to readily locate, access, and use data from distributed and diverse sources. Both disciplines must address the issue of how to distribute these massive data sets to the science community. Distributable media (DVD) are too expensive due to their limited storage capacity and the network bandwidth is unlikely to be able to support online distribution.

Walker, R. J.; Joy, S. P.; King, T. A.

2003-12-01

196

An integrated mission planning approach for the Space Exploration initiative  

NASA Astrophysics Data System (ADS)

This report discusses a fully integrated energy-based approach to mission planning which is needed if the Space Exploration Initiative (SEI) is to succeed. Such an approach would reduce the number of new systems and technologies requiring development. The resultant horizontal commonality of systems and hardware would reduce the direct economic impact of SEI and provide an economic benefit by greatly enhancing our international technical competitiveness through technology spin-offs and through the resulting early return on investment. Integrated planning and close interagency cooperation must occur if the SEI is to achieve its goal of expanding the human presence into the solar system and be an affordable endeavor. An energy-based mission planning approach gives each mission planner the needed power, yet preserves the individuality of mission requirements and objectives while reducing the concessions mission planners must make. This approach may even expand the mission options available and enhance mission activities.

Coomes, E. P.; Dagle, J. E.; Bamberger, J. A.; Noffsinger, K. E.

1992-08-01

197

An integrated mission planning approach for the Space Exploration Initiative  

SciTech Connect

This report discusses a fully integrated energy-based approach to mission planning which is needed if the Space Exploration Initiative (SEI) is to succeed. Such an approach would reduce the number of new systems and technologies requiring development. The resultant horizontal commonality of systems and hardware would reduce the direct economic impact of SEI and provide an economic benefit by greatly enhancing our international technical competitiveness through technology spin-offs and through the resulting early return on investment. Integrated planning and close interagency cooperation must occur if the SEI is to achieve its goal of expanding the human presence into the solar system and be an affordable endeavor. An energy-based mission planning approach gives each mission planner the needed power, yet preserves the individuality of mission requirements and objectives while reducing the concessions mission planners must make. This approach may even expand the mission options available and enhance mission activities.

Coomes, E.P.; Dagle, J.E.; Bamberger, J.A.; Noffsinger, K.E.

1992-08-01

198

An integrated mission planning approach for the space exploration initiative  

SciTech Connect

A fully integrated energy-based approach to mission planning is needed if the Space Exploration Initiative (SEI) is to succeed. Such an approach would reduce the number of new systems and technologies requiring development. The resultant horizontal commonality of systems and hardware would reduce the direct economic impact of SEI and provide an economic benefit by greatly enhancing our international technical competitiveness through technology spin-offs and through the resulting early return on investment. Integrated planning and close interagency cooperation must occur if the SEI is to achieve its goal of expanding the human presence into the solar system and be an affordable endeavor. An energy-based mission planning approach gives each mission planner the needed power, yet preserves the individuality of mission requirements and objectives while reducing the concessions mission planners must make. This approach may even expand the mission options available and enhance mission activities.

Coomes, E.P.; Dagle, J.E.; Bamberger, J.A.; Noffsinger, K.E.

1992-01-01

199

Exploring lexical co-occurrence space using HiDEx.  

PubMed

Hyperspace analog to language (HAL) is a high-dimensional model of semantic space that uses the global co-occurrence frequency of words in a large corpus of text as the basis for a representation of semantic memory. In the original HAL model, many parameters were set without any a priori rationale. We have created and publicly released a computer application, the High Dimensional Explorer (HiDEx), that makes it possible to systematically alter the values of these parameters to examine their effect on the co-occurrence matrix that instantiates the model. We took an empirical approach to understanding the influence of the parameters on the measures produced by the models, looking at how well matrices derived with different parameters could predict human reaction times in lexical decision and semantic decision tasks. New parameter sets give us measures of semantic density that improve the model's ability to predict behavioral measures. Implications for such models are discussed. PMID:20479171

Shaoul, Cyrus; Westbury, Chris

2010-05-01

200

Power-Beaming Concepts for Future Deep Space Exploration  

NASA Astrophysics Data System (ADS)

We explore uses of thermal desorption of materials from prepared LEO sails, which can give additional propulsion when struck by intense microwave beams from the ground. Beam heating of a sail until its surface coat sublimes or desorps can add far more thrust, roughly a factor of 1000. Beamed power from Earth can heat sails to temperatures >1000 K, both to drive them to high velocities and to simulate similar conditions for very near-Sun missions. This approach promises to make microwave- riding sails greatly superior to both solar sails and laser-driven sails, because it uses the best features of both, in a wavelength region of maximum utility. A natural collaboration emerges between subliming and/or desorping sails driven by microwave beams in LEO, becoming high velocity solar sails for the long mission. Resonant boosting from repeated shots can liberate sails in weeks into interplanetary space. Spinning sails by using polarized beams can deploy sails. A Mars Fast Track mission to speeds ~50 km/sec may be possible with an enhanced Deep Space Network. With this array one could test near-sun conditions for desorption in a Sun-Diver mission, enabling high-speed near-interstellar voyages.

Benford, G.; Benford, J.

201

Systems and Technologies for Space Exploration: the regional project STEPS  

NASA Astrophysics Data System (ADS)

The Aerospace technology network of Piemonte represents ˜25% of the italian capacity and handles a comprehensive spectrum of products (aircraft, propulsion, satellites, space station modules, avionics. components, services...). The cooperation between the Comitato Distretto Aerospaziale Piemonte and the European Regional Development Fund 2007-2013 has enabled Regione Piemonte to launch three regional Projects capable to enhance the synergy and competitiveness of the network, among which: STEPS - Sistemi e Tecnologie per l'EsPlorazione Spaziale, a joint development of technologies for robotic and human Space Exploration by 3 large Industries, 27 SMEs, 3 Universities and one public Research Centre. STEPS develops virtual and hardware demonstrators for a range of technologies to do with a Lander's descent and soft landing, and a Rover's surface mobility, of both robotic and manned equipment on Moon and Mars. It also foresees the development of Teleoperations labs and Virtual Reality environments and physical simulations of Moon and Mars surface conditions and ground. Mid-way along STEPS planned development, initial results in several technology domains are available and are presented in this paper.

Boggiatto, D.; Moncalvo, D.

202

Collective control of spacecraft swarms for space exploration  

NASA Astrophysics Data System (ADS)

Swarms are characterized in nature by a dynamic behaviour which is quite appealing for researchers involved in numerous fields of study, like robotics, computer science, pure mathematics and space sciences. Global group organization acquired in absence of centralized control is the feature of natural swarms which is most interesting to reproduce. This study proposes to make use of some evolutionary robotics findings in order to obtain the autonomous group organization in the framework of a deeper knowledge of the astrodynamics. The main task which will be accomplished is the implementation of the control laws for the single satellite. A careful tuning of the parameters at member level is necessary in order to gain an autonomously evolving global behaviour in a number of space missions of immediate interest. In remote sensing missions, for example, trains of a small number of satellites are already orbiting and integrating their collected data: in near future entire swarms of agents could accomplish this task, and should be controlled in order to acquire and maintain the desired leader-follower configuration. Another example can be seen in deep space exploration of unknown celestial bodies, where the migration of the entire swarm from a reference orbit to a (previously unknown) targeted one is an issue; the same group migration is of interest in Earth orbit, when transferring from parking to operational orbit. Finally, self-assembly of rigid-like virtual structures is also simulated. This paper shows that all these cases are autonomously performed by the swarm by correctly implementing four simple rules at individual level, which assess the primal needs for any satellite: avoid collision, remain grouped, align to the neighbor, reach a goal.

Sabatini, Marco; Palmerini, Giovanni B.

2009-11-01

203

Three near term commercial markets in space and their potential role in space exploration  

NASA Astrophysics Data System (ADS)

Independent market studies related to Low Earth Orbit (LEO) commercialization have identified three near term markets that have return-on-investment potential. These markets are: (1) Entertainment (2) Education (3) Advertising/sponsorship. Commercial activity is presently underway focusing on these areas. A private company is working with the Russians on a commercial module attached to the ISS that will involve entertainment and probably the other two activities as well. A separate corporation has been established to commercialize the Russian Mir Space Station with entertainment and promotional advertising as important revenue sources. A new startup company has signed an agreement with NASA for commercial media activity on the International Space Station (ISS). Profit making education programs are being developed by a private firm to allow students to play the role of an astronaut and work closely with space scientists and astronauts. It is expected that the success of these efforts on the ISS program will extend to exploration missions beyond LEO. The objective of this paper is to extrapolate some of the LEO commercialization experiences to see what might be expected in space exploration missions to Mars, the Moon and beyond. .

Gavert, Raymond B.

2001-02-01

204

Exploration of the Equilibrium Operating Space For NSTX-Upgrade  

SciTech Connect

This paper explores a range of high-performance equilibrium scenarios available in the NSTX-Upgrade device [J.E. Menard, submitted for publication to Nuclear Fusion]. NSTX-Upgrade is a substantial upgrade to the existing NSTX device [M. Ono, et al., Nuclear Fusion 40, 557 (2000)], with significantly higher toroidal field and solenoid capabilities, and three additional neutral beam sources with significantly larger current drive efficiency. Equilibria are computed with freeboundary TRANSP, allowing a self consistent calculation of the non-inductive current drive sources, the plasma equilibrium, and poloidal field coil current, using the realistic device geometry. The thermal profiles are taken from a variety of existing NSTX discharges, and different assumptions for the thermal confinement scalings are utilized. The no-wall and idealwall n=1 stability limits are computed with the DCON code. The central and minimum safety factors are quite sensitive to many parameters: they generally increases with large outer plasmawall gaps and higher density, but can have either trend with the confinement enhancement factor. In scenarios with strong central beam current drive, the inclusion of non-classical fast ion diffusion raises qmin, decreases the pressure peaking, and generally improves the global stability, at the expense of a reduction in the non-inductive current drive fraction; cases with less beam current drive are largely insensitive to additional fast ion diffusion. The non-inductive current level is quite sensitive to the underlying confinement and profile assumptions. For instance, for BT=1.0 T and Pinj=12.6 MW, the non-inductive current level varies from 875 kA with ITER-98y,2 thermal confinement scaling and narrow thermal profiles to 1325 kA for an ST specific scaling expression and broad profiles. This sensitivity should facilitate the determination of the correct scaling of transport with current and field to use for future fully non-inductive ST devices. Scenarios are presented which can be sustained for 8-10 seconds, or (20-30)?CR, at ?N=3.8-4.5, facilitating, for instance, the study of disruption avoidance for very long pulse. Scenarios have been documented which can operate with ?T~25% and equilibrated qmin>1. The value of qmin can be controlled at either fixed non-inductive fraction of 100% or fixed plasma current, by varying which beam sources are used, opening the possibility for feedback qmin control. In terms of quantities like collisionality, neutron emission, non-inductive fraction, or stored energy, these scenarios represent a significant performance extension compared to NSTX and other present spherical torii.

S.P. Gerhardt, R. Andre and J.E. Menard

2012-04-25

205

Exploration of the equilibrium operating space for NSTX-Upgrade  

NASA Astrophysics Data System (ADS)

This paper explores a range of high-performance equilibrium scenarios achievable with neutral beam heating in the NSTX-Upgrade device (Menard J.E. 2012 Nucl. Fusion 52 083015). NSTX-Upgrade is a substantial upgrade to the existing NSTX device (Ono M. et al 2000 Nucl. Fusion 40 557), with significantly higher toroidal field and solenoid capabilities, and three additional neutral beam sources with significantly larger current-drive efficiency. Equilibria are computed with free-boundary TRANSP, allowing a self-consistent calculation of the non-inductive current-drive sources, the plasma equilibrium and poloidal-field coil currents, using the realistic device geometry. The thermal profiles are taken from a variety of existing NSTX discharges, and different assumptions for the thermal confinement scalings are utilized. The no-wall and ideal-wall n = 1 stability limits are computed with the DCON code. The central and minimum safety factors are quite sensitive to many parameters: they generally increase with large outer plasma-wall gaps and higher density, but can have either trend with the confinement enhancement factor. In scenarios with strong central beam current drive, the inclusion of non-classical fast-ion diffusion raises qmin, decreases the pressure peaking, and generally improves the global stability, at the expense of a reduction in the non-inductive current-drive fraction; cases with less beam current drive are largely insensitive to additional fast-ion diffusion. The non-inductive current level is quite sensitive to the underlying confinement and profile assumptions. For instance, for BT = 1.0 T and Pinj = 12.6 MW, the non-inductive current level varies from 875 kA with ITER-98y,2 thermal confinement scaling and narrow thermal profiles to 1325 kA for an ST specific scaling expression and broad profiles. Scenarios are presented which can be sustained for 8-10 s, or (20-30) ?CR, at ?N = 3.8-4.5. The value of qmin can be controlled at either fixed non-inductive fraction of 100% or fixed plasma current, by varying which beam sources are used, opening the possibility for feedback control of the current profile. In terms of quantities like collisionality, neutron emission, non-inductive fraction, or stored energy, these scenarios represent a significant performance extension compared with NSTX and other present spherical torii.

Gerhardt, S. P.; Andre, R.; Menard, J. E.

2012-08-01

206

14 CFR 1266.104 - Cross-waiver of liability for launch agreements for science or space exploration activities...  

Code of Federal Regulations, 2010 CFR

...liability for launch agreements for science or space exploration activities unrelated...liability for launch agreements for science or space exploration activities unrelated...parties to agreements for NASA's science or space exploration activities that...

2011-01-01

207

14 CFR 1266.104 - Cross-waiver of liability for launch agreements for science or space exploration activities...  

Code of Federal Regulations, 2010 CFR

...liability for launch agreements for science or space exploration activities...to agreements for NASA's science or space exploration activities...party to a NASA agreement for science or space exploration activities...profits; or (iv) Other direct, indirect, or...

2009-01-01

208

Efficient exploration of the space of reconciled gene trees.  

PubMed

Gene trees record the combination of gene-level events, such as duplication, transfer and loss (DTL), and species-level events, such as speciation and extinction. Gene tree-species tree reconciliation methods model these processes by drawing gene trees into the species tree using a series of gene and species-level events. The reconstruction of gene trees based on sequence alone almost always involves choosing between statistically equivalent or weakly distinguishable relationships that could be much better resolved based on a putative species tree. To exploit this potential for accurate reconstruction of gene trees, the space of reconciled gene trees must be explored according to a joint model of sequence evolution and gene tree-species tree reconciliation. Here we present amalgamated likelihood estimation (ALE), a probabilistic approach to exhaustively explore all reconciled gene trees that can be amalgamated as a combination of clades observed in a sample of gene trees. We implement the ALE approach in the context of a reconciliation model (Szöll?si et al. 2013), which allows for the DTL of genes. We use ALE to efficiently approximate the sum of the joint likelihood over amalgamations and to find the reconciled gene tree that maximizes the joint likelihood among all such trees. We demonstrate using simulations that gene trees reconstructed using the joint likelihood are substantially more accurate than those reconstructed using sequence alone. Using realistic gene tree topologies, branch lengths, and alignment sizes, we demonstrate that ALE produces more accurate gene trees even if the model of sequence evolution is greatly simplified. Finally, examining 1099 gene families from 36 cyanobacterial genomes we find that joint likelihood-based inference results in a striking reduction in apparent phylogenetic discord, with respectively. 24%, 59%, and 46% reductions in the mean numbers of duplications, transfers, and losses per gene family. The open source implementation of ALE is available from https://github.com/ssolo/ALE.git. [amalgamation; gene tree reconciliation; gene tree reconstruction; lateral gene transfer; phylogeny.]. PMID:23925510

Szöllosi, Gergely J; Rosikiewicz, Wojciech; Boussau, Bastien; Tannier, Eric; Daubin, Vincent

2013-08-06

209

Efficient Exploration of the Space of Reconciled Gene Trees  

PubMed Central

Gene trees record the combination of gene-level events, such as duplication, transfer and loss (DTL), and species-level events, such as speciation and extinction. Gene tree–species tree reconciliation methods model these processes by drawing gene trees into the species tree using a series of gene and species-level events. The reconstruction of gene trees based on sequence alone almost always involves choosing between statistically equivalent or weakly distinguishable relationships that could be much better resolved based on a putative species tree. To exploit this potential for accurate reconstruction of gene trees, the space of reconciled gene trees must be explored according to a joint model of sequence evolution and gene tree–species tree reconciliation. Here we present amalgamated likelihood estimation (ALE), a probabilistic approach to exhaustively explore all reconciled gene trees that can be amalgamated as a combination of clades observed in a sample of gene trees. We implement the ALE approach in the context of a reconciliation model (Szöll?si et al. 2013), which allows for the DTL of genes. We use ALE to efficiently approximate the sum of the joint likelihood over amalgamations and to find the reconciled gene tree that maximizes the joint likelihood among all such trees. We demonstrate using simulations that gene trees reconstructed using the joint likelihood are substantially more accurate than those reconstructed using sequence alone. Using realistic gene tree topologies, branch lengths, and alignment sizes, we demonstrate that ALE produces more accurate gene trees even if the model of sequence evolution is greatly simplified. Finally, examining 1099 gene families from 36 cyanobacterial genomes we find that joint likelihood-based inference results in a striking reduction in apparent phylogenetic discord, with respectively. 24%, 59%, and 46% reductions in the mean numbers of duplications, transfers, and losses per gene family. The open source implementation of ALE is available from https://github.com/ssolo/ALE.git. [amalgamation; gene tree reconciliation; gene tree reconstruction; lateral gene transfer; phylogeny.

Szollosi, Gergely J.; Rosikiewicz, Wojciech; Boussau, Bastien; Tannier, Eric; Daubin, Vincent

2013-01-01

210

Space medicine innovation and telehealth concept implementation for medical care during exploration-class missions  

NASA Astrophysics Data System (ADS)

Medical care on the International Space Station (ISS) is provided using real-time communication with limited medical data transmission. In the occurrence of an off-nominal medical event, the medical care paradigm employed is ‘stabilization and transportation’, involving real-time management from ground and immediate return to Earth in the event that the medical contingency could not be resolved in due time in space. In preparation for future missions beyond Low-Earth orbit (LEO), medical concepts of operations are being developed to ensure adequate support for the new mission profiles: increased distance, duration and communication delays, as well as impossibility of emergency returns and limitations in terms of medical equipment availability. The current ISS paradigm of medical care would no longer be adequate due to these new constraints. The Operational Space Medicine group at the Canadian Space Agency (CSA) is looking towards synergies between terrestrial and space medicine concepts for the delivery of medical care to deal with the new challenges of human space exploration as well as to provide benefits to the Canadian population. Remote and rural communities on Earth are, in fact, facing similar problems such as isolation, remoteness to tertiary care centers, resource scarcity, difficult (and expensive) emergency transfers, limited access to physicians and specialists and limited training of medical and nursing staff. There are a number of researchers and organizations, outside the space communities, working in the area of telehealth. They are designing and implementing terrestrial telehealth programs using real-time and store-and-forward techniques to provide isolated populations access to medical care. The cross-fertilization of space-Earth research could provide support for increased spin-off and spin-in effects and stimulate telehealth and space medicine innovations to engage in the new era of human space exploration. This paper will discuss the benefits of space-Earth research projects for the advancement of both terrestrial and space medicine and will use examples of operational space medicine projects conducted at the CSA in areas such as remote training, tele-mentoring and remote control of an ultrasound.

Martin, Annie; Sullivan, Patrick; Beaudry, Catherine; Kuyumjian, Raffi; Comtois, Jean-Marc

2012-12-01

211

Exploring the Use of Online Space in an Elementary School  

ERIC Educational Resources Information Center

|This paper analysed how three teacher-researchers of Singapore's elementary school used online space extensively in Grade 2-Grade 4 classrooms. Such online space, made possible by free and readily available web 2.0 and open source applications, was meant to complement the physical learning space as such space can allow learning activities, which…

Lye, Sze Yee; Abas, Suriati; Tay, Lee Yong; Saban, Fadilah

2012-01-01

212

Exploring predictions of safe operating spaces for human water use  

NASA Astrophysics Data System (ADS)

In the Nature article 'A safe operating space for humanity', Rockström et al. (2009) introduce the idea of a safe space for human activities that will not push the planet out of the 'Holocene state'. Rockström et al. have identified nine earth-system processes and associated thresholds which, if crossed, are expected to generate unacceptable environmental change. Rockström et al. (2009) focus on the scientific prediction of these thresholds. Concerning the use of these boundaries for public policy, these authors limit their efforts to concluding that the evidence so far suggests that, as long as the thresholds are not crossed, humanity has the freedom to pursue long-term social and economic development. The approach advocated by Rockström et al. (2009) is plagued by two related problems: uncertainty and dynamic complexity (Molden, 2009; Brewer, 2009). The latter problem addresses the reductionist approach of Rockström et al and argues, in opposition, that the limits on each of the nine earth-system processes are co-depended and thus the safe operating space constitutes a single multi-dimensional space that can only be identified holistically. The first problem is that our current scientific knowledge and understanding of the earth system is incomplete and partly contested. A majority of the authors reacting on the global limit concept do however emphasize their relevance as "targets for policy makers". However, the two problems imply that the establishment of predicted global limits as a substantive base for public policy is meaningless. Still, the presence of scientific uncertainty and dynamic complexity and thus the omnipresence of unpredictability need not be used as an excuse to ignore the importance of a substantive grounding of these policies. In this paper, we argue and show how despite dynamic complexity and irreducible uncertainty, policies can be designed, tested, and shown to be effective in reaching broad social goals related to social and economic development. To this end, we utilize ANEMI (Davies and Simonovic, 2011), a dynamic impact assessment model of the planetary fresh water cycle and related systems (e.g. economy, land use, population, and climate). We assess the dynamics of this model over a broad range of different uncertainties; we identify combinations of uncertainties that produce dynamics that threaten the flourishing of humanity, and use these insights to develop public policies that can counteract these undesirable dynamics.

Kwakkel, J. H.; Timmermans, J. S.

2012-04-01

213

Use of antarctic analogs to support the space exploration initiative  

NASA Astrophysics Data System (ADS)

This report has discussed the Space Exploration Initiative (SEI) and the U.S. Antarctic Program (USAP) in the context of assessing the potential rationale and strategy for conducting a cooperative NASA/NSF (National Science Foundation) effort. Specifically, such an effort would address shared research and data on living and conducting scientific research in isolated, confined, hostile, and remote environments. A review of the respective goals and requirements of NASA and the NSF indicates that numerous opportunities exist to mutually benefit from sharing relevant technologies, data, and systems. Two major conclusions can be drawn: (1) The technologies, experience, and capabilities existing and developing in the aerospace community would enhance scientific research capabilities and the efficiency and effectiveness of operations in Antarctica. The transfer and application of critical technologies (e.g., power, waste management, life support) and collaboration on crew research needs (e.g., human behavior and medical support needs) would streamline the USAP operations and provide the scientific community with advancements in facilities and tools for Antarctic research. (2) Antarctica is the most appropriate earth analog for the environments of the the Moon and Mars. Using Antarctica in this way would contribute substantially to near- and long-term needs and plans for the SEI. Antarctica is one of the few ground-based analogs that would permit comprehensive and integrated studies of three areas deemed critical to productive and safe operations on the Moon and Mars: human health and productivity; innovative scientific research techniques; and reliable, efficient technologies and facilities.

Wharton, Robert; Roberts, Barney; Chiang, Erick; Lynch, John; Roberts, Carol; Buoni, Corinne; Andersen, Dale

1990-12-01

214

Space and surface power for the space exploration initiative: Results from project outreach  

NASA Astrophysics Data System (ADS)

The analysis and evaluations of the Space and Surface Power panel, one of eight panels created by RAND to screen and analyze submissions to the Space Exploration Initiative (SEI) Outreach Program, is documented. In addition to managing and evaluating the responses, or submissions, to this public outreach program, RAND conducted its own analysis and evaluation relevent to SEI mission concepts, systems, and technologies. The Power panel screened and analyzed submissions for which a substantial portion of the concepts involved power generation sources, transmission, distribution, thermal management, and handling of power (including conditioning, conversion, packaging, and enhancements in system components). A background discussion of the areas the Power panel covered and the issues the reviewers considered pertinent to the analysis of power submissions are presented. An overview of each of the highest-ranked submissions and then a discussion of these submissions is presented. The results of the analysis is presented.

Shipbaugh, C.; Solomon, K.; Gonzales, D.; Juncosa, M.; Bauer, T.; Salter, R.

215

{sup 238}PuO{sub 2} heat sources: An enabling technology for space exploration  

SciTech Connect

Surprisingly, during the 35 yr that {sup 238}PuO{sub 2}-fueled radioisotope power systems have been demonstrated and continuously improved in terms of safety, reliability, and efficiency, US capabilities to produce {sup 238}PuO{sub 2} have significantly decreased. At the same time, progress in the efficiency and longevity of chemical and solar power systems has reduced the suite of potential applications for radioisotope power systems remain a viable option for deep space exploration and planetary missions that must survive hostile operating environments. The enabling aspect of radioisotope power supplies for deep space exploration missions can best be illustrated by a comparative analysis of power supply options available for the National Aeronautics and Space Administration`s most recent planetary explorer, the Cassini mission to Saturn. A comparative evaluation of currently available power supply options for the Cassini mission, demonstrates the significant mass and maneuverability penalties that would result from the use of chemical or solar energy sources in place of the RTGs and heater units. Absent additional nuclear power options, such as a spacecraft reactor, radioisotope power sources were clearly the only viable option for providing electrical and thermal power to the Cassini spacecraft.

George, T.G. [Los Alamos National Lab., NM (United States)

1998-12-31

216

Human factors and nuclear space technology in long-term exploration  

SciTech Connect

Allocation of manual versus automated tasks for operation and maintenance of nuclear power systems in space will be crucial at the onset and at the return of a space flight. Such factors as space adaptation syndrome (SAS), a temporary space motion sickness that has affected 40 to 50% of crew members on past space flights, can result in lost effort ranging from a few hours to a full day. This could have a significant impact on manual performance where high levels of execution are likely to be required in the very early stages of the mission. Other considerations involving higher-level behavioral phenomena such as interpersonal and group processes, individual belief systems, social and motivational factors, and (subjective) cognitive function have received little attention; nevertheless these will be essential elements for success in long-term exploration. Understanding that long-term space flight missions may create groups that become unique societies distinct unto themselves will test current ethical, moral, and social belief systems, requiring one to examine the amalgamation as well as organizational structures for the safety and balance of the crew.

Brown-VanHoozer, S.A.; VanHoozer, W.R.

2000-07-01

217

National Space Biomedical Research Institute Education and Public Outreach Program: Education for the next generation of space explorers  

Microsoft Academic Search

The National Space Biomedical Research Institute (NSBRI) Education and Public Outreach Program (EPOP) is supporting the National Aeronautics and Space Administration's (NASA) new vision for space exploration by educating and inspiring the next generation of students through a seamless pipeline of kindergarten through postdoctoral education programs. NSBRI EPOP initiatives are designed to train scientists and to communicate the significance of

Marlene Y. MacLeish; William A. Thomson; Nancy Moreno; Patrick J. Gannon; Roland B. Smith; Clifford W. Houston; Gary Coulter; Gregory L. Vogt

2007-01-01

218

Giving children space: A phenomenological exploration of student experiences in space science inquiry  

NASA Astrophysics Data System (ADS)

This study explores the experiences of 4th grade students in an inquiry-based space science classroom. At the heart of the study lies the essential question: What is the lived experience of children engaged in the process of space science inquiry? Through the methodology of phenomenological inquiry, the author investigates the essence of the lived experience of twenty 4th grade students as well as the reflections of two high school students looking back on their 4th grade space science experience. To open the phenomenon more deeply, the concept of space is explored as an overarching theme throughout the text. The writings of several philosophers including Martin Heidegger and Hans-Georg Gadamer are opened up to understand the existential aspects of phenomenology and the act of experiencing the classroom as a lived human experience. The methodological structure for the study is based largely on the work of Max van Manen (2003) in his seminal work, Researching Lived Experience, which describes a structure of human science research. A narrative based on classroom experiences, individual conversations, written reflections, and group discussion provides insight into the students' experiences. Their stories and thoughts reveal the themes of activity , interactivity, and "inquiractivity," each emerging as an essential element of the lived experience in the inquiry-based space science classroom. The metaphor of light brings illumination to the themes. Activity in the classroom is associated with light's constant and rapid motion throughout the Milky Way and beyond. Interactivity is seen through students' interactions just as light's reflective nature is seen through the illumination of the planets. Finally, inquiractivity is connected to questioning, the principal aspect of the inquiry-based classroom just as the sun is the essential source of light in our solar system. As the era of No Child Left Behind fades, and the next generation of science standards emerge, the students' stories are viewed through the lens of the scientific practices found in A Framework for K-12 Science Education (The National Research Council, 2011). The critical challenge for elementary educators interacting with this text is to find the lived meaning of giving children space in an inquiry-based experience.

Horne, Christopher R.

219

Current and future air force space cryogenic technology development  

NASA Astrophysics Data System (ADS)

Current space cryocooler developments have achieved performance and capability that have made the use of active refrigeration in space missions feasible. Several space flight demonstrations and operational programs have baselined and implemented active refrigeration to achieve mission goals. The application of cryocooler technology validates the progress achieved to enable improved mission capabilities and reliability and lifetime confidence in active refrigeration in space. Past development efforts have focused primarily on reliability and the achievement of long life. However, future military space applications have renewed focus on improvements needed in several aspects of current cooling technology including higher capacity cooling loads, multistage cooling, mass reduction, and improvement in efficiency, low temperature performance, and lifetimes greater than 10 years. In addition, due to the potential for large system parasitic heat penalties, cryogenic integration technology is currently being developed to allow efficient cryocooler to cooled component integration. This paper will focus on the current and future developments at the Air Force Research Laboratory (AFRL), Space Vehicles Directorate for advanced cryogenic integration technology. .

Tomlinson, B. J.; Davis, T. M.; Hill, S. D.; Bruninghaus, C. H.

2002-05-01

220

NASA Exploration Team (NExT) In-Space Transportation Overview.  

National Technical Information Service (NTIS)

This presentation provides an overview of NASA Exploration Team's (NEXT) vision of in-space transportation in the future. Hurdles facing in-space transportation include affordable power sources, crew health and safety, optimized robotic and human operatio...

B. G. Drake D. R. Cooke L. D. Kos

2002-01-01

221

Recent advances in nuclear powered electric propulsion for space exploration  

Microsoft Academic Search

Nuclear and radioisotope powered electric thrusters are being developed as primary in space propulsion systems for potential future robotic and piloted space missions. Possible applications for high-power nuclear electric propulsion include orbit raising and maneuvering of large space platforms, lunar and Mars cargo transport, asteroid rendezvous and sample return, and robotic and piloted planetary missions, while lower power radioisotope electric

R. Joseph Cassady; Robert H. Frisbee; James H. Gilland; Michael G. Houts; Michael R. LaPointe; Colleen M. Maresse-Reading; Steven R. Oleson; James E. Polk; Derrek Russell; Anita Sengupta

2008-01-01

222

From ISS to Human Space Exploration: TAS-I contribution and perspectives  

Microsoft Academic Search

The paper describes the contribution of Thales Alenia Space Italia (TAS-I) in Torino to the Human Space Exploration starting from the participation to the International Space Station (ISS) up to the new perspectives in the fields of the Space Habitats, Transportation Systems and related technologies. The contribution of more than 50% of the habitable volume of the ISS is underlined

P. Messidoro

2011-01-01

223

"Festival of Flight Special": Opening Space for Next Generation Explorers. NASA CONNECT[TM]. [Videotape].  

ERIC Educational Resources Information Center

|The National Aeronautics and Space Administration's (NASA) Space Launch Initiative (SLI) Program will ultimately move from the explorations of the Mercury, Gemini, Apollo, and Space Shuttle missions to a new period of pioneering in which people and businesses are more routinely traveling, working, and living in space. (Author/NB)|

National Aeronautics and Space Administration, Hampton, VA. Langley Research Center.

224

Viewpoints: A New Computer Program for Interactive Exploration of Large Multivariate Space Science and Astrophysics Data.  

NASA Astrophysics Data System (ADS)

The graphics processing units (GPUs) built in to all professional desktop and laptop computers currently on the market are capable of transforming, filtering, and rendering hundreds of millions of points per second. We present a prototype open-source cross-platform (windows, linux, Apple OSX) application which leverages some of the power latent in the GPU to enable smooth interactive exploration and analysis of large high-dimensional data using a variety of classical and recent techniques. The targeted application area is the interactive analysis of complex, multivariate space science and astrophysics data sets, with dimensionalities that may surpass 100 and sample sizes that may exceed 10^6-10^8.

Levit, Creon; Gazis, P.

2006-06-01

225

Exploration of the Chemical Space of Group 4 Polymer Dielectrics  

NASA Astrophysics Data System (ADS)

The current standards for capacitive energy storage applications are polypropylene (PP) and polyethylene (PE) which have large band gap and high breakdown strength, but a small dielectric constant. The envisaged next generation dielectric should provide high dielectric constant, while still preserving the insulating characteristics of PP and PE. To meet these growing needs, we use high throughput density functional theory (DFT) calculations in combination with machine learning (ML) methods to identify classes of polymers with large dielectric constant and band gap. In our work, we consider various possible local chemical modifications to polyethylene (PE). To be specific, we allow the -CH2- unit in the PE backbone segment to be replaced by -SiF2-, -SiCl2-, -GeF2-, -GeCl2-, -SnF2-, or -SnCl2- units in a systematic manner. High throughput methods were used first to accurately determine the dielectric constant and band gap of the chemically modified PE chains for a set of limited compositions and configurations. ML methods were then used to predict the properties of systems spanning a much larger part of the configurational and compositional space. A set of most promising PE modifications (with simultaneously large dielectric constant and band gap) is identified using this strategy.

Wang, Chenchen; Pilania, Ghanshyam; Ramprasad, Rampi

2013-03-01

226

Fiber lasers and amplifiers for space-based science and exploration  

NASA Astrophysics Data System (ADS)

We present current and near-term uses of high-power fiber lasers and amplifiers for NASA science and spacecraft applications. Fiber lasers and amplifiers offer numerous advantages for the deployment of instruments on exploration and science remote sensing satellites. Ground-based and airborne systems provide an evolutionary path to space and a means for calibration and verification of space-borne systems. NASA fiber-laser-based instruments include laser sounders and lidars for measuring atmospheric carbon dioxide, oxygen, water vapor and methane and a pulsed or pseudo-noise (PN) code laser ranging system in the near infrared (NIR) wavelength band. The associated fiber transmitters include high-power erbium, ytterbium, and neodymium systems and a fiber laser pumped optical parametric oscillator. We discuss recent experimental progress on these systems and instrument prototypes for ongoing development efforts.

Yu, Anthony W.; Krainak, Michael A.; Stephen, Mark A.; Chen, Jeffrey R.; Coyle, Barry; Numata, Kenji; Camp, Jordan B.; Abshire, James B.; Allan, Graham R.; Li, Steven X.; Riris, Haris

2012-02-01

227

Exploring the universe with the Hubble Space Telescope  

NASA Astrophysics Data System (ADS)

A general overview is given of the operations, engineering challenges, and components of the Hubble Space Telescope. Deployment, checkout and servicing in space are discussed. The optical telescope assembly, focal plane scientific instruments, wide field/planetary camera, faint object spectrograph, faint object camera, Goddard high resolution spectrograph, high speed photometer, fine guidance sensors, second generation technology, and support systems and services are reviewed.

228

Exploration Space Suit Architecture: Destination Environmental-Based Technology Development.  

National Technical Information Service (NTIS)

This paper picks up where EVA Space Suit Architecture: Low Earth Orbit Vs. Moon Vs. Mars (Hill, Johnson, IEEEAC paper no. 1209) left off in the development of a space suit architecture that is modular in design and interfaces and could be reconfigured to ...

T. R. Hill

2010-01-01

229

The synergy of biology, intelligent systems, and space exploration  

Microsoft Academic Search

The authors discuss some of the ways that intelligent systems are advancing the understanding of human and other genomes as well as the molecular regulatory mechanisms for gene expression. They also extrapolate and speculate on space applications that could result from this new understanding of biology, in such areas as human spaceflight (including space medicine and life support systems), NASA's

E. Mjolsness; A. Tavormina

2000-01-01

230

Exploring design space for an integrated intelligent system  

Microsoft Academic Search

Understanding the trade-offs available in the design space of intelligent systems is a major unaddressed element in the study of Artificial Intelligence. In this paper we approach this problem in two ways. First, we discuss the development of our integrated robotic system in terms of its trajectory through design space. Second, we demonstrate the practical implications of architectural design decisions

Nick Hawes; Jeremy Wyatt; Aaron Sloman

2009-01-01

231

Toys in Space: Exploring Science with the Astronauts.  

ERIC Educational Resources Information Center

|The purpose of the Toys in Space project was to create new ways for children to discover the joy and excitement of science and technology in the world around us. This book describes how familiar toys behave in the space environment where the downward pull of gravity is absent, and clearly documents those principles of physics that explain why the…

Sumners, Carolyn

232

THE VALUE OF HUMANS IN THE BIOLOGICAL EXPLORATION OF SPACE  

Microsoft Academic Search

.  Regardless of the discovery of life on Mars, or of “no apparent life” on Mars, the questions that follow will provide a rich future for biological exploration. Extraordinary pattern recognition skills, decadal assimilation of data and experience, and rapid sample acquisition are just three of the characteristics that make humans the best means we have to explore the biological potential

C. S. COCKELL

2004-01-01

233

Leveraging exploration capabilites for space-based astronomical observatories  

NASA Astrophysics Data System (ADS)

Recent work done in preparation for a potential robotic mission to the Hubble Space Telescope has verified that the capability now exists to assemble, upgrade, and service large space-based telescopes robotically. This paper recommends that future space-based telescopes explicitly take this capability into account and plan for periodic robotic upgrades and servicing, just as the Hubble Space Telescope planned for periodic human upgrades and servicing. A single robotic servicing spacecraft stored at the Earth-Moon Lagrangian point, EML1, can readily provide capabilities for assembly, instrument and component replacements, and routine and emergency servicing for all future space telescopes located in Earth orbit or at the Earth-Sun Lagrangian points, ESL1 and ESL2.

Stevens, John; King, Dan

2005-08-01

234

Currents limited by the space charge in ice  

NASA Astrophysics Data System (ADS)

The currents limited by the space charge in ice are studied theoretically and experimentally. A value for the mobility of the most mobile current carriers, H3O(+) ions, is found by comparing theoretical calculations with the results of a proton injection experiment in frozen distilled water with an initial resistivity of (0.9 to 0.3) x 10 to the 7th ohms/cm.

Petrenko, V. F.; Ryzhkin, I. A.

1984-08-01

235

Temporal partitioning combined with design space exploration for latency minimization of run-time reconfigured designs  

Microsoft Academic Search

We present combined temporal partitioning and design space exploration techniques for synthesizing behavioral specifications for run-time reconfigurable processors. De- sign space exploration involves selecting a design point for each task from a set of design points for that task to achieve latency minimization of partitioned solutions. We present an iterative search procedure that uses a core ILP (Integer Linear Programming)

Meenakshi Kaul; Ranga Vemuri

1999-01-01

236

Temporal partitioning combined with design space exploration for latency minimization of run-time reconfigured designs  

Microsoft Academic Search

We present combined temporal partitioning and design space exploration techniques for synthesizing behavioral specifications for run-time reconfigurable processors. Design space exploration involves selecting a design point for each task from a set of design points for that task to achieve latency minimization of partitioned solutions. We present an iterative search procedure that uses a core ILP (integer linear programming) technique,

Meenakshi Kaul; Ranga Vemuri

1999-01-01

237

Building and maintaining the constituency for long-term space exploration  

Microsoft Academic Search

The exploration of space is a long-term endeavor that will require strong public support to weather societal and political changes over the period of its implementation. In August 2006, George Mason University's Center for Aerospace Policy Research organized a workshop to address this issue. The sustainability of space exploration was investigated from a variety of perspectives by invited experts from

Peggy Finarelli; Ian Pryke

2007-01-01

238

Rapid design space exploration using legacy design data and technology scaling trend  

Microsoft Academic Search

Rapid and effective design space exploration at all stages of a design process enables faster design convergence and shorter time-to-market. This is particularly important during the early stage of a design where design decisions can have a significant impact on design convergence. This paper describes a methodology for design space exploration using design target prediction models. These models are driven

Charles Thangaraj; Alkan Cengiz; Tom Chen

2010-01-01

239

Heavy ions, radioprotectors and genomic instability: implications for human space exploration.  

PubMed

The risk associated with space radiation exposure is unique from terrestrial radiation exposures due to differences in radiation quality, including linear energy transfer (LET). Both high- and low-LET radiations are capable of inducing genomic instability in mammalian cells, and this instability is thought to be a driving force underlying radiation carcinogenesis. Unfortunately, during space exploration, flight crews cannot entirely avoid radiation exposure. As a result, chemical and biological countermeasures will be an important component of successful extended missions such as the exploration of Mars. There are currently several radioprotective agents (radioprotectors) in use; however, scientists continue to search for ideal radioprotective compounds-safe to use and effective in preventing and/or reducing acute and delayed effects of irradiation. This review discusses the agents that are currently available or being evaluated for their potential as radioprotectors. Further, this review discusses some implications of radioprotection for the induction and/or propagation of genomic instability in the progeny of irradiated cells. PMID:20035342

Dziegielewski, Jaroslaw; Goetz, Wilfried; Baulch, Janet E

2009-12-25

240

Space transfer concepts and analyses for exploration missions, phase 3  

NASA Astrophysics Data System (ADS)

This report covers the third phase of a broad-scoped and systematic study of space transfer concepts for human lunar and Mars missions. The study addressed issues that were raised during Phase 2, developed generic Mars missions profile analysis data, and conducted preliminary analysis of the Mars in-space transportation requirements and implementation from Stafford Committee Synthesis Report. The major effort of the study was the development of the first Lunar Outpost (FLO) baseline which evolved from the Space Station Freedom Hab Module. Modifications for the First Lunar Outpost were made to meet mission requirements and technology advancements.

Woodcock, Gordon R.

1993-06-01

241

Advanced Water Recovery Technologies for Long Duration Space Exploration Missions.  

National Technical Information Service (NTIS)

Extended-duration space travel and habitation require recovering water from wastewater generated in spacecrafts and extraterrestrial outposts since the largest consumable for human life support is water. Many wastewater treatment technologies used for ter...

S. X. Liu

2005-01-01

242

Hematopoietic Stem Cell Therapy for Exploration of Space.  

National Technical Information Service (NTIS)

Astronauts experience severe/invasive disorders caused by space environments. These include hematological/cardiac abnormalities, bone and muscle losses, immunodeficiency, neurological disorders and cancer. While the cause of these symptoms are not yet ful...

A. N. Roach J. Brezo B. C. Kim S. Ohi

2000-01-01

243

The Henrietta Leavitt Flat Screen Space Theater: Explorations in Astronomy  

NSDL National Science Digital Library

The Henrietta Leavitt Flat Screen Space Theater is named for an American astronomer working at the Harvard Observatory in the beginning of this century. The site is authored by Carolyn Collins Petersen, an accomplished astronomy writer and part-time Hubble researcher. Carolyn takes viewers to "The Planetarium Show That Never Ends," where various heavenly bodies are displayed and described in non-scientific but informative and inspiring ways. Next stop is the "The Space Image Gallery" where we can view beautiful photos of star birth, Jupiter's Moons, and the Cat's Eye Nebula, all with brief, lucid descriptions. The Flat Screen Space Theater is not so much educational as it is inspirational for those of us who haven't stopped recently to view the photos coming back from space, and so have forgotten what all the fuss is about.

1995-01-01

244

Language, Space, Time: Anthropological Tools and Scientific Exploration on Mars.  

National Technical Information Service (NTIS)

This viewgraph presentation reviews the importance of social science disciplines in the scientific exploration of Mars. The importance of language, workspace, and time differences are reviewed. It would appear that the social scientist perspective in deve...

R. Wales

2005-01-01

245

Exploring Design Space For An Integrated Intelligent System  

Microsoft Academic Search

\\u000a Understanding the trade-offs available in the design space of intelligent systems is a major unaddressed element in the study\\u000a of Artificial Intelligence. In this paper we approach this problem in two ways. First, we discuss the development of our integrated\\u000a robotic system in terms of its trajectory through design space. Second, we demonstrate the practical implications of architectural\\u000a design decisions

Nick Hawes; Jeremy Wyatt; Aaron Sloman

2009-01-01

246

Exploration of Unknown Spaces by People Who Are Blind Using a Multi-sensory Virtual Environment  

ERIC Educational Resources Information Center

|The ability to explore unknown spaces independently, safely and efficiently is a combined product of motor, sensory, and cognitive skills. Normal exercise of this ability directly affects an individual?s quality of life. Mental mapping of spaces and of the possible paths for navigating these spaces is essential for the development of efficient…

Lahav, Orly; Mioduser, David

2004-01-01

247

Mars Wars: The Rise and Fall of the Space Exploration Initiative  

Microsoft Academic Search

The rise of Space Exploration Initiative (SEI) and its eventual demise represents one of the landmark episodes in the history of the American space program ranking with the creation of NASA, the decision to go to the Moon, the post-Apollo planning process, and the space station decision. The story of this failed initiative is one shaped by key protagonists and

Thor Hogan

2007-01-01

248

New Heavy-Lift Capability for Space Exploration: NASA's Ares V Cargo Launch Vehicle.  

National Technical Information Service (NTIS)

The National Aeronautics and Space Administration (NASA) is developing new launch systems in preparation for the retirement of the Space Shuttle by 2010, as directed in the United States (U.S.) Vision for Space Exploration. The Ares I Crew Launch Vehicle ...

J. P. Sumrall

2006-01-01

249

Social Interaction History: A Framework for Supporting Exploration of Social Information Spaces  

Microsoft Academic Search

Abstract— Social interaction history refers to traces of social interaction in information spaces. These traces have potential to help users explore and navigate through information spaces. Indigital spaces, however, past records of social interaction are often hidden or underutilized. As a result, users cannot use social navigation to guide their movement while browsing information collections. We developed a conceptual framework

Indratmo; Julita Vassileva

2009-01-01

250

Space Travel is Utter Bilge: Early Ideas on Interplanetary Exploration  

NASA Astrophysics Data System (ADS)

Until a few decades ago, interplanetary travel was the stuff of dreams but the dreamers often turned out to be farsighted while the predictions of some eminent scientists were far too conservative. The prescient dreamers include the Russian schoolteacher, Konstanin Tsiolkovsky who, in 1883, was the first to note that only rockets could serve the needs of space travel. In 1923, Herman Oberth published a treatise discussing various aspects of interplanetary travel including the impulse necessary to escape the Earth's gravitational pull. In his spare time, a German civil engineer, Walter Hohmann, established in 1925 that the optimal energy transfer orbit between planets is an ellipse that is tangent to the orbits of both bodies. Four year later, an Austrian army officer, Hermann Potocnik outlined the benefits of space stations including those in geosynchronous orbits. Whereas Tsiolkovsky, Oberth, Hohmann, and Potocnik provided ideas and theories, the American, Robert H. Goddard, was testing liquid fueled rockets by as early as 1925. By the time he was finished in 1941, Goddard flew liquid fueled rockets that reached speeds of 700 mph and altitudes above 8,000 feet. In direct contrast to the advances by these mostly amateur engineers, many respected authorities scoffed at space travel because of the insurmountable technological difficulties. One year prior to the launch of Sputnik, the British Astronomer Royal, Sir Richard Wooley, declared, "space travel is utter bilge." While the theories of space travel were well developed by the late 1920's, space travel technology was still a poorly funded, mostly amateur, endeavor until the German army hired Oberth's student, Werner von Braun, and others to develop long range rockets for military purposes. In the early 1940's, Von Braun's team developed the rocket propulsion and guidance systems that would one day form the basis of the American space program.

Yeomans, D. K.

2003-12-01

251

Spaceward Bound: Field Training for the Next Generation of Space Explorers  

NASA Astrophysics Data System (ADS)

Spaceward Bound is an educational program developed at NASA Ames to train the next generation of space explorers where students and teachers participate in the exploration of interesting, remote and extreme environments — analogs for human exploration of the Moon and Mars.

Coe, L. K.; Sun, H.; McKay, C. P.

2010-04-01

252

Building long-term constituencies for space exploration: The challenge of raising public awareness and engagement in the United States and in Europe  

NASA Astrophysics Data System (ADS)

Space exploration is a multifaceted endeavor and will be a "grand challenge" of the 21st century. It has already become an element of the political agenda of a growing number of countries worldwide. However, the public is largely unaware of space exploration activities and in particular does not perceive any personal benefit. In order to achieve highly ambitious space exploration goals to explore robotically and with humans the inner solar system, space agencies must improve and expand their efforts to inform and raise the awareness of the public about what they are doing, and why. Therefore adopting new techniques aiming at informing and engaging the public using participatory ways, new communication techniques to reach, in particular, the younger generation will be a prerequisite for a sustainable long-term exploration program: as they will enable it and carry most of the associated financial burden. This paper presents an environmental analysis of space exploration in the United States and Europe and investigates the current branding stature of the National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA). We discuss how improved market research and new branding methods can increase public space awareness and improve the image of NASA and ESA. We propose a new participatory approach to engage the public as major stakeholder (along governments, the industrial space sector and the science community) that may provide sufficient resources for and sustainability of a long-term space exploration program.

Ehrenfreund, P.; Peter, N.; Billings, L.

2010-08-01

253

Human exploration of space: why, where, what for?  

PubMed

"Man must rise above Earth to the top of the atmosphere and beyond, for only then will he fully understand the world in which he lives"-Socrates (469-399 BC). The basic driving rationales for human space flight (HSF) are rooted in age-old and persisting dreams. Fascination with the idea of people going into the sky for adventures in other worlds goes back to ancient myths. This paper sheds light onto criticisms of HSF programs, by revisiting their scientific grounds and associated benefits, along with the different types of emerging commercial enterprise. Research from space has lead to a wealth of commercial and societal applications on Earth, building up the case for the so-called "Space Applications Market". PMID:19048086

Vernikos, J

2008-08-01

254

The Current Status of Low Frequency Radio Astronomy from Space  

NASA Astrophysics Data System (ADS)

Ground-based radio astronomy is severely limited by the Earth's ionosphere. Below 15 -- 20 MHz, space-based radio observations are superior or even mandatory. Three different areas of astronomical research manifest themselves at low radio frequencies: solar, planetary, and galactic-extragalactic. Space-based observations of solar phenomena at low frequencies are a natural extension of high-frequency ground-based observations that have been carried out since the beginnings of radio astronomy. Measurements of known solar phenomena such as Types II and III bursts have been extended from the few solar radii altitude range reachable by ground-based techniques out to 1 AU and beyond. These space-based solar measurements have become critical in our developing an understanding of ``space weather." In contrast, non-thermal planetary radio emissions are almost exclusively a space radio astronomy phenomenon. With the exception of two components of Jupiter's complex radio spectrum, the magnetospheric and Auroral radio emissions of Earth, Jupiter, Saturn, Uranus, and Neptune have all been discovered by space radio astronomy techniques. For astrophysical applications, the lack of angular resolution from space at low frequencies has thwarted progress such that most areas still remain to be fully exploited. Results to date have only included overall cosmic background spectra and extremely crude (~1 steradian resolution) ``maps." In this overview we will briefly summarize the current status of science in the three areas of research and outline some future concepts for low-frequency, space-based instruments for solar, planetary, and astrophysical problems.

Kaiser, M. L.; Weiler, K. W.

255

Integrating Collaborative Distributed Simulations for Space Exploration Missions  

Microsoft Academic Search

This paper describes the architecture and implementation of a distributed simulation of NASA's Orion spacecraft and Ares launch vehicle in a mission to the International Space Station. The simulation is part of the Integrated Mission Simulation (IMSim) project which aims at research and development collaboration among NASA centers. As mission systems are complex, a distributed simulation allows participating centers to

Esther H. Jennings; Michael G. Blum; Juan M. Busto; Victoria Chung; Joe Hawkins

256

Exploring the Distant Universe With the Spitzer Space Telescope  

Microsoft Academic Search

The infrared Spitzer Space Telescope is the last of NASA's Great Observatories. Highlights of the first results from the Infrared Spectrograph (IRS) Extragalactic Team are given. The main focus of this paper is a demonstration of the unprecedented sensitivity of the IRS, which makes observations of distant, dust enshrouded galaxies possible.

Sarah J. U. Higdon; James L. Higdon; Dan Weedman; James R. Houck; B. T. Soifer; Lee Armus; Vassilis Charmandaris; Terry L. Herter

2004-01-01

257

Solar Power Satellites for Space Exploration and Applications  

Microsoft Academic Search

Power generation is one of the crucial elements of space vehicles and of future infrastructures on planets and moons. The increased demand for power faces many constraints, in particular the sizing of the power generation system also driven by eclipse periods and the solar intensity at the operational spot. In the medium term, Earth orbiting platforms will require higher power

C. Cougnet; E. Sein; A. Celeste; L. Summerer

2004-01-01

258

Systems and Technologies for Space Exploration: the regional project STEPS  

Microsoft Academic Search

The Aerospace technology network of Piemonte represents ˜25% of the italian capacity and handles a comprehensive spectrum of products (aircraft, propulsion, satellites, space station modules, avionics. components, services...). The cooperation between the Comitato Distretto Aerospaziale Piemonte and the European Regional Development Fund 2007-2013 has enabled Regione Piemonte to launch three regional Projects capable to enhance the synergy and competitiveness of

D. Boggiatto; D. Moncalvo

2011-01-01

259

Exploring the Optimization Space of Dense Linear Algebra Kernels  

Microsoft Academic Search

Dense linear algebra kernels such as matrix multiplication have been used as benchmarks to evaluate the effectiveness of many au- tomated compiler optimizations. However, few studies have looked at collectively applying the transformations and parameterizing them for external search. In this paper, we take a detailed look at the optimiza- tion space of three dense linear algebra kernels. We use

Qing Yi; Apan Qasem

2008-01-01

260

From Early Exploration to Space Weather Forecasts: Canada's Geomagnetic Odyssey  

NASA Astrophysics Data System (ADS)

Canada is a region ideally suited for the study of space weather: The north magnetic pole is encompassed within its territory, and the auroral oval traverses its vast landmass from east to west. Magnetic field lines link the country directly to the outer magnetosphere. In light of this geographic suitability, it has been a Canadian tradition to install ground monitors to remotely sense the space above Canadian territory. The beginning of this tradition dates back to 1840, when Edward Sabine, a key figure in the “magnetic crusade” to establish magnetic observatories throughout the British Empire in the nineteenth century, founded the first Canadian magnetic observatory on what is now the campus of the University of Toronto, 27 years before the birth of Canada. This observatory, which later became the Toronto Magnetic and Meteorological Observatory, marked the beginning of the Canadian heritage of installing magnetic stations and other ground instruments in the years to come. This extensive network of ground-based measurement devices, coupled with space-based measurements in more modern times, has enabled Canadian researchers to contribute significantly to studies related to space weather.

Lam, Hing-Lan

2011-05-01

261

Survey of intra- and intermission flexibility in space exploration systems  

Microsoft Academic Search

An increasingly common objective in the design of new space systems is the property of flexibility, or the capability to easily modify a system after it has been fielded in response to a changing environment or changing requirements. The body of research on this topic has been growing, but substantial work remains in developing metrics for characterizing system flexibility and

Jarret M. Lafleur; Joseph H. Saleh

2010-01-01

262

The liquid annular reactor system (LARS) for deep space exploration  

Microsoft Academic Search

A new propulsion concept for high ? V space missions, termed LARS (Liquid Annular Reactor System), uses liquid nuclear fuel elements to heat hydrogen propellant to very high temperatures (-6000 K). The molten fuel is contained in a lower-temperature solid container which rotates to stabilize and hold in the liquid layer by centripetal force. Containment of ultra high temperature molten

H. Ludewig; M. Todosow; J. R. Powell

1999-01-01

263

Contested Cultural Spaces: Exploring Illicit Drug-Using through "Trainspotting"  

ERIC Educational Resources Information Center

|Contending that culture is one of the most potentially divisive signifiers of human activity, this paper probes some of the complexities that attend the (un)popular culture of illicit drug-using with which many young people in contemporary Britain are identified. Irvine Welsh's multi-media drugs narrative "Trainspotting" is drawn on to explore…

Hemingway, Judy

2006-01-01

264

Negotiating Displacement Spaces: Exploring Teachers' Stories about Learning and Diversity  

ERIC Educational Resources Information Center

The purpose of this qualitative investigation was to explore the learning of six in-service U.S. teachers who engaged in a cross-cultural learning experience during the summer of 2001. The teachers were enrolled in a graduate seminar conducted in English and entitled "Literacy Across Languages and Cultures." Cindy (the first author of this…

Brock, Cynthia; Wallace, Jill; Herschbach, Michelle; Johnson, Christine; Raikes, Bill; Warren, Kim; Nikoli, Melissa; Poulsen, Holland

2006-01-01

265

Negotiating Displacement Spaces: Exploring Teachers' Stories about Learning and Diversity  

ERIC Educational Resources Information Center

|The purpose of this qualitative investigation was to explore the learning of six in-service U.S. teachers who engaged in a cross-cultural learning experience during the summer of 2001. The teachers were enrolled in a graduate seminar conducted in English and entitled "Literacy Across Languages and Cultures." Cindy (the first author of this…

Brock, Cynthia; Wallace, Jill; Herschbach, Michelle; Johnson, Christine; Raikes, Bill; Warren, Kim; Nikoli, Melissa; Poulsen, Holland

2006-01-01

266

Time to imagine space: a chronometric exploration of representational neglect  

Microsoft Academic Search

When describing known places from memory, patients with left spatial neglect may mention more right- than left-sided items, thus showing representational, or imaginal, neglect. This suggests that these patients cannot either build or explore left locations in visual mental imagery. However, in place description there is no guarantee that patients are really employing visual mental imagery abilities, rather than verbal-propositional

Paolo Bartolomeo; Anne-Catherine Bachoud-Lévi; Philippe Azouvi; Sylvie Chokron

2005-01-01

267

NASA Selects Next Generation of Space Explorers; Google+ Hangout Today  

NASA Website

After an extensive year-and-a-half search, NASA has a new group of potential astronauts who will help the agency push the boundaries of exploration and travel to new destinations in the solar system, including an asteroid and Mars.

268

Future space explorations in the bio-nano millennium  

Microsoft Academic Search

Some of the fundamental questions that NASA has outlined in its 2000 Strategic Plan include investigating how did the universe, galaxies, stars, and planets form and evolve, and what is their destiny; does life in any form exist (or has it existed) elsewhere in the universe; how can our exploration of the universe and our solar system revolutionize our understanding

Leon Alkalai

269

Scalable partitioning and exploration of chemical spaces using geometric hashing.  

PubMed

Virtual screening (VS) has become a preferred tool to augment high-throughput screening(1) and determine new leads in the drug discovery process. The core of a VS informatics pipeline includes several data mining algorithms that work on huge databases of chemical compounds containing millions of molecular structures and their associated data. Thus, scaling traditional applications such as classification, partitioning, and outlier detection for huge chemical data sets without a significant loss in accuracy is very important. In this paper, we introduce a data mining framework built on top of a recently developed fast approximate nearest-neighbor-finding algorithm(2) called locality-sensitive hashing (LSH) that can be used to mine huge chemical spaces in a scalable fashion using very modest computational resources. The core LSH algorithm hashes chemical descriptors so that points close to each other in the descriptor space are also close to each other in the hashed space. Using this data structure, one can perform approximate nearest-neighbor searches very quickly, in sublinear time. We validate the accuracy and performance of our framework on three real data sets of sizes ranging from 4337 to 249 071 molecules. Results indicate that the identification of nearest neighbors using the LSH algorithm is at least 2 orders of magnitude faster than the traditional k-nearest-neighbor method and is over 94% accurate for most query parameters. Furthermore, when viewed as a data-partitioning procedure, the LSH algorithm lends itself to easy parallelization of nearest-neighbor classification or regression. We also apply our framework to detect outlying (diverse) compounds in a given chemical space; this algorithm is extremely rapid in determining whether a compound is located in a sparse region of chemical space or not, and it is quite accurate when compared to results obtained using principal-component-analysis-based heuristics. PMID:16426067

Dutta, Debojyoti; Guha, Rajarshi; Jurs, Peter C; Chen, Ting

270

Space charge templates for high-current beam modeling  

SciTech Connect

A computational method to evaluate space charge potential and gradients of charged particle beam in the presence of conducting boundaries, has been introduced. The three-dimensional (3D) field of the beam can be derived as a convolution of macro Green's functions (template fields), satisfying the same boundary conditions, as the original beam. Numerical experiments gave a confidence that space charge effects can be modeled by templates with enough accuracy and generality within dramatically faster computational times than standard combination: a grid density + Poisson solvers, realized in the most of Particle in Cell codes. The achieved rapidity may significantly broaden the high-current beam design space, making the optimization in automatic mode possible, which so far was only feasible for simplest self-field formulations such as rms envelope equations. The template technique may be used as a standalone program, or as an optional field solver in existing beam dynamics codes both in one-passage structures and in rings.

Vorobiev, Leonid G.; /Fermilab

2008-07-01

271

Identifying organic molecules in space: the AstroBiology Explorer (ABE) MIDEX misson concept  

NASA Astrophysics Data System (ADS)

In this paper we review our current state of knowledge regarding the identity of organic and related compounds in the interstellar medium (ISM). The remote detection and identification of organics is ideally suited to the technique of infrared spectroscopy since such data can be obtained telescopically and this spectral range encompasses the fundamental vibrational modes of common molecular bonds. Despite recent advances in our knowledge of the organic component of the ISM, we are still far from understanding the distribution, abundance and evolutionary inter- relationship of these materials within our galaxy and the universe as a whole. Many of these issues can be addressed by the acquisition of new infrared spectra. We briefly describe a potential new Explorer-class space mission capable of obtaining such data, the AstroBiology Explorer (ABE) which consists of a space observatory capable of obtaining spectra in the 2.5-16.0 micrometers range at a spectral resolution of (Delta) $lamda/(lambda) equals 2000-3000. ABE would be capable of addressing outstanding problems in Astrochemistry and Astrophysics that are particularly relevant to Astrobiology and addressable via astronomical observation. ABE would have approximately one year lifetime during which it would obtain a coordinated set of infrared spectroscopic observations of large numbers of galaxies, stars, planetary nebulae, interstellar clouds, young star planetary systems and objects within our own Solar System.

Sandford, Scott; Allamandola, Louis; Bregman, Jesse D.; Ennico, Kimberly A.; Greene, Thomas P.; Hudgins, Douglas; Strecker, Donald W.

2002-02-01

272

Exploration of DGVM Parameter Solution Space Using Simulated Annealing: Implications for Forecast Uncertainties  

NASA Astrophysics Data System (ADS)

Parameters in dynamic global vegetation models (DGVMs) are thought to be weakly constrained and can be a significant source of errors and uncertainties. DGVMs use between 5 and 26 plant functional types (PFTs) to represent the average plant life form in each simulated plot, and each PFT typically has a dozen or more parameters that define the way it uses resource and responds to the simulated growing environment. Sensitivity analysis explores how varying parameters affects the output, but does not do a full exploration of the parameter solution space. The solution space for DGVM parameter values are thought to be complex and non-linear; and multiple sets of acceptable parameters may exist. In published studies, PFT parameters are estimated from published literature, and often a parameter value is estimated from a single published value. Further, the parameters are "tuned" using somewhat arbitrary, "trial-and-error" methods. BIOMAP is a new DGVM created by fusing MAPSS biogeography model with Biome-BGC. It represents the vegetation of North America using 26 PFTs. We are using simulated annealing, a global search method, to systematically and objectively explore the solution space for the BIOMAP PFTs and system parameters important for plant water use. We defined the boundaries of the solution space by obtaining maximum and minimum values from published literature, and where those were not available, using +/-20% of current values. We used stratified random sampling to select a set of grid cells representing the vegetation of the conterminous USA. Simulated annealing algorithm is applied to the parameters for spin-up and a transient run during the historical period 1961-1990. A set of parameter values is considered acceptable if the associated simulation run produces a modern potential vegetation distribution map that is as accurate as one produced by trial-and-error calibration. We expect to confirm that the solution space is non-linear and complex, and that multiple acceptable parameter sets exist. Further we expect to demonstrate that the multiple parameter sets produce significantly divergent future forecasts in NEP, C storage, and ET and runoff; and thereby identify a highly important source of DGVM uncertainty

Wells, J. R.; Kim, J. B.

2011-12-01

273

Exploring the conformational space of FRET biosensors for improved designs  

NASA Astrophysics Data System (ADS)

Fusion proteins are an important class of proteins with diverse applications in biotechnology. They consist of 2 or more rigid domains joined by a flexible linker. Understanding the conformational space of fusion proteins conferred by the flexible linkers is important to predicting its behavior. In this paper, we introduce a modeling tool called FPMOD (Fusion Protein MODeller) which samples the conformational space of fusion proteins by treating all domains as rigid bodies and rotating each of them around their flexible linkers. As a demonstration, FPMOD was used to predict the fluorescence resonance energy transfer (FRET) efficiency of three different fusion protein biosensors. The simulation results of the FRET efficiency prediction were consistent with the in vitro experimental data, which verified that FPMOD is a valid tool to predicting the behavior of fusion proteins.

Truong, Kevin; Pham, Elizabeth

2008-02-01

274

Design space exploration for optimizing on-chip communication architectures  

Microsoft Academic Search

Rapid growth in the complexity of system-on-chips is being accompanied by increasing volume and diversity of on-chip communi- cation traffic,which in turn,is driving the development of advanced system-level communication architectures. While these architectures have the potential to improve system performance,they pose significant new challenges to the system designer,owing to the complex design space de- fined by the availability of numerous

Kanishka Lahiri; Anand Raghunathan; Sujit Dey

2004-01-01

275

Collective control of spacecraft swarms for space exploration  

Microsoft Academic Search

Swarms are characterized in nature by a dynamic behaviour which is quite appealing for researchers involved in numerous fields\\u000a of study, like robotics, computer science, pure mathematics and space sciences. Global group organization acquired in absence\\u000a of centralized control is the feature of natural swarms which is most interesting to reproduce. This study proposes to make\\u000a use of some evolutionary

Marco Sabatini; Giovanni B. Palmerini

2009-01-01

276

The role of nuclear reactors in space exploration and development  

Microsoft Academic Search

The United States has launched more than 20 radioisotopic thermoelectric generators (RTGs) into space over the past 30 yr but has launched only one nuclear reactor, and that was in 1965. Russia has launched more than 30 reactors. The RTGs use the heat of alpha decay of ²³⁸Pu for power and typically generate <1 kW of electricity. Apollo, Pioneer, Voyager,

Lipinski

2000-01-01

277

Exploration of the Chemical Space of Public Genomic Databases  

EPA Science Inventory

The current project aims to chemically index the content of public genomic databases to make these data accessible in relation to other publicly available, chemically-indexed toxicological information. ...

278

Space and Architecture's Current Line of Research? A Lunar Architecture Workshop With An Architectural Agenda.  

NASA Astrophysics Data System (ADS)

The "2002 ESA Lunar Architecture Workshop" (June 3-16) ESTEC, Noordwijk, NL and V2_Lab, Rotterdam, NL) is the first-of-its-kind workshop for exploring the design of extra-terrestrial (infra) structures for human exploration of the Moon and Earth-like planets introducing 'architecture's current line of research', and adopting an architec- tural criteria. The workshop intends to inspire, engage and challenge 30-40 European masters students from the fields of aerospace engineering, civil engineering, archi- tecture, and art to design, validate and build models of (infra) structures for Lunar exploration. The workshop also aims to open up new physical and conceptual terrain for an architectural agenda within the field of space exploration. A sound introduc- tion to the issues, conditions, resources, technologies, and architectural strategies will initiate the workshop participants into the context of lunar architecture scenarios. In my paper and presentation about the development of the ideology behind this work- shop, I will comment on the following questions: * Can the contemporary architectural agenda offer solutions that affect the scope of space exploration? It certainly has had an impression on urbanization and colonization of previously sparsely populated parts of Earth. * Does the current line of research in architecture offer any useful strategies for com- bining scientific interests, commercial opportunity, and public space? What can be learned from 'state of the art' architecture that blends commercial and public pro- grammes within one location? * Should commercial 'colonisation' projects in space be required to provide public space in a location where all humans present are likely to be there in a commercial context? Is the wave in Koolhaas' new Prada flagship store just a gesture to public space, or does this new concept in architecture and shopping evolve the public space? * What can we learn about designing (infra-) structures on the Moon or any other space context that will be useful on Earth on a conceptual and practical level? * In what ways could architecture's field of reference offer building on the Moon (and other celestial bodies) a paradigm shift? 1 In addition to their models and designs, workshop participants will begin authoring a design recommendation for the building of (infra-) structures and habitats on celestial bodies in particular the Moon and Mars. The design recommendation, a substantiated aesthetic code of conduct (not legally binding) will address long term planning and incorporate issues of sustainability, durability, bio-diversity, infrastructure, CHANGE, and techniques that lend themselves to Earth-bound applications. It will also address the cultural implications of architectural design might have within the context of space exploration. The design recommendation will ultimately be presented for peer review to both the space and architecture communities. What would the endorsement from the architectural community of such a document mean to the space community? The Lunar Architecture Workshop is conceptualised, produced and organised by(in alphabetical order): Alexander van Dijk, Art Race in Space, Barbara Imhof; ES- CAPE*spHERE, Vienna, University of Technology, Institute for Design and Building Construction, Vienna, Bernard Foing; ESA SMART1 Project Scientist, Susmita Mo- hanty; MoonFront, LLC, Hans Schartner' Vienna University of Technology, Institute for Design and Building Construction, Debra Solomon; Art Race in Space, Dutch Art Institute, Paul van Susante; Lunar Explorers Society. Workshop locations: ESTEC, Noordwijk, NL and V2_Lab, Rotterdam, NL Workshop dates: June 3-16, 2002 (a Call for Participation will be made in March -April 2002.) 2

Solomon, D.; van Dijk, A.

279

Human Space Exploration and Radiation Exposure from EVA: 1981-2011  

NASA Astrophysics Data System (ADS)

There are several risks for any human space exploration endeavor. One such inevitable risk is exposure to the space radiation environment of which extra vehicular activity (EVA) demands more challenges due to limited amount of protection from space suit shielding. We recently compiled all EVA data comprising low-earth orbit (LEO) from Space Shuttle (STS) flights, International Space Station (ISS) expeditions, and Shuttle-Mir missions. Assessment of such radiation risk is very important, particularly for the anticipated long-term, deep-space human explorations in the near future. We present our assessment of anticipated radiation exposure and space radiation dose contribution to each crew member from a listing of 350 different EVA events resulting in more than 1000+ hrs of total EVA time. As of July 12, 2011, 197 astronauts have made spacewalks (out of 520 people who have gone into Earth orbit). Only 11 women have been on spacewalks.

Way, A. R.; Saganti, S. P.; Erickson, G. M.; Saganti, P. B.

2011-12-01

280

The Hematopoietic Stem Cell Therapy for Exploration of Space  

NASA Astrophysics Data System (ADS)

Departments of Biochemistry &Molecular Biology, Genetics &Human Genetics, Pediatrics &Child Long-duration space missions require countermeasures against severe/invasive disorders in astronauts that are caused by space environments, such as hematological/cardiac abnormalities, bone/muscle losses, immunodeficiency, neurological disorders, and cancer. Some, if not all, of these disorders may be amenable to hematopoietic stem cell therapy and gene therapy. Growing evidence indicates that hematopoietic stem cells (HSCs) possess extraordinary plasticity to differentiate not only to all types of blood cells but also to various tissues, including bone, muscle, skin, liver and neuronal cells. Therefore, our working hypothesis is that the hematopoietic stem cell-based therapy, herein called as the hematopoietic stem cell therapy (HSCT), might provide countermeasure/prevention for hematological abnormalities, bone and muscle losses in space, thereby maintaining astronauts' homeostasis. Our expertise lies in recombinant adeno-associated virus (rAAV)-mediated gene therapy for the hemoglobinopathies, -thalassemia and sickle cell disease (Ohi S, Kim BC, J Pharm Sci 85: 274-281, 1996; Ohi S, et al. Grav Space Biol Bull 14: 43, 2000). As the requisite steps in this protocol, we established procedures for purification of HSCs from both mouse and human bone marrow in 1 G. Furthermore, we developed an easily harvestable, long-term liquid suspension culture system, which lasts more than one year, for growing/expanding HSCs without stromal cells. Human globin cDNAs/gene were efficiently expressed from the rAAVs in the mouse HSCs in culture. Additionally, the NASA Rotating Wall Vessel (RWV) culture system is being optimized for the HSC growth/expansion. Thus, using these technologies, the above hypothesis is being investigated by the ground-based experiments as follows: 1) -thalassemic mice (C57BL/6-Hbbth/Hbbth, Hbd-minor) are transplanted with normal isologous HSCs to correct the hematological abnormalities. To date, the - thalassemic mice have been successfully HSC-transplanted to produce chimerism of hemoglobin species (Ohi S, J Grav Physiol 7: 67-68, 2000); 2) Transgenic HSCs harboring green fluorescent protein (GFP) gene or -galactosidase gene are/will be transplanted to hindlimb suspended mice, and differentiation of HSCs to bone will be traced by the marker gene expression. Repair/prevention of bone loss by the HSCT will be investigated by analyzing physical/biochemical parameters; 3) Similarly, the efficacy of HSCT for muscle loss in the unloaded mouse is being studied. In addition, using the hindlimb suspension model, effects of exercise on the HSCT for bone and muscle losses are being investigated. Our long-term goal is to automate/robotize the HSCT protocols so that astronauts would be able to treat themselves during long-duration space missions. Such a program will be also beneficial to the earth people as a self-care health system. Upon optimization of the condition of HSC growth in the RWV culture system, it is in our plan to conduct the similar experiments as above in the International Space Station in future. (Supported in part by grant from NASA Institute for Advanced Concepts/USRA.

Ohi, S.

281

Class Explorations in Space: From the Blackboard and History to the Outdoors and Future  

NASA Astrophysics Data System (ADS)

Our everyday activities occur so seamlessly in the space around us as to leave us unawares of space, its properties, and our use of it. What might we notice, wonder about and learn through interacting with space exploratively? My seminar class took on that question as an opening for personal and group experiences during this semester. In the process, they observe space locally and in the sky, read historical works of science involving space, and invent and construct forms in space. All these actions arise responsively, as we respond to: physical materials and space; historical resources; our seminar participants, and future learners. Checks, revisions and further developments -- on our findings, geometrical constructions, shared or personal inferences---come about observationally and collaboratively. I teach this seminar as an expression of the research pedagogy of critical exploration, developed by Eleanor Duckworth from the work of Jean Piaget, B"arbel Inhelder and the Elementary Science Study. This practice applies the quest for understanding of a researcher to spontaneous interactions evolving within a classroom. The teacher supports students in satisfying and developing their curiosities, which often results in exploring the subject matter by routes that are novel to both teacher and student. As my students ``mess about'' with geometry, string and chalk at the blackboard, in their notebooks, and in response to propositions in Euclid's Elements, they continually imagine further novel venues for using geometry to explore space. Where might their explorations go in the future? I invite you to hear from them directly!

Cavicchi, Elizabeth

2011-11-01

282

EXPLORING TRANSITIONS OF SPACE PLASMAS OUT OF EQUILIBRIUM  

SciTech Connect

Space plasmas from the solar wind to planetary magnetospheres and the outer heliosphere are systems in stationary states out of equilibrium. Empirical kappa distributions, which naturally emerge from Tsallis Statistics, successfully describe these space plasmas. The Tsallis formalism offers a solid statistical foundation and provides a set of proven tools for understanding these distributions, including a consistent definition of temperature-the physical temperature, which characterizes the non-equilibrium stationary states. Here, we develop a measure of the 'thermodynamic distance' of stationary states away from equilibrium. The stationary states are labeled by the value of the entropic q-index, lying in a spectrum from q = 1 (equilibrium) to the maximum value of q, which specifies the furthest possible stationary state from equilibrium. We call this the 'q-frozen state', because as a system approaches this state, it behaves analogously to when its temperature approaches absolute zero. We also introduce a novel isothermal procedure that describes a system's transition into different stationary states by varying the q-index, and show how the variation of temperature can be realized using an 'iso-metastability' procedure, in which the system remains in a fixed stationary state. These innovations allow a generalization of the zeroth law of thermodynamics to cover stationary states out of equilibrium. By expressing the entropy in terms of the q-index, we show the detailed paths by which the transition of stationary states evolves toward equilibrium following the dynamics of a characteristic difference equation along the q-indices. This naturally exhibits certain stationary states out of equilibrium that are frequently observed in space plasmas.

Livadiotis, G.; McComas, D. J. [Southwest Research Institute, San Antonio, TX 78238 (United States)

2010-05-01

283

A methodology to support strategic decisions in future human space exploration: From scenario definition to building blocks assessment  

NASA Astrophysics Data System (ADS)

The human exploration of multiple deep space destinations (e.g. Cis-Lunar, NEAs), in view of the final challenge of sending astronauts to Mars, represents a current and consistent study domain especially in terms of its possible scenarios and mission architectures assessments, as proved by the numerous on-going activities about this topic and moreover by the global exploration roadmap. After exploring and analysing different possible solutions to identify the most flexible path, a detailed characterisation of several Design Reference Missions (DRMs) represents a necessity in order to evaluate the feasibility and affordability of deep space exploration missions, specifically in terms of enabling technological capabilities. The study presented in this paper was aimed at defining an evolutionary scenario for deep space exploration in the next 30 years with the final goal of sending astronauts on the surface of Mars by the end of 2030 decade. Different destinations were considered as targets to build the human exploration scenario, with particular attention to Earth-Moon Lagrangian points, NEA and Moon. For all the destinations selected as part of the exploration scenario, the assessment and characterisation of the relative Design Reference Missions were performed. Specifically they were defined in terms of strategies, architectures and mission elements. All the analyses were based on a pure technical approach with the objective of evaluating the feasibility of a long term strategy for capabilities achievement and technological development to enable future space exploration. This paper describes the process that was followed within the study, focusing on the adopted methodology, and reports the major obtained results, in terms of scenario and mission analysis.

Viscio, Maria Antonietta; Gargioli, Eugenio; Hoffman, Jeffrey A.; Maggiore, Paolo; Messidoro, Andrea; Viola, Nicole

2013-10-01

284

Ocean Surface Current Monitoring from Space: Methodology and Progress  

NASA Astrophysics Data System (ADS)

Monitoring the ocean surface currents is a primary application of the highly successful satellite altimetry missions that started 15 years ago. This symposium coincides with the implementation of a significant achievement of the NOAA Ocean Surface Current Analyses Real-time project (OSCAR, http://www.oscar.noaa.gov), namely the extension of satellite-derived surface current processing, and its associated datacenter, to the global ocean. We present a synthesis of the efforts resulting in the estimation of surface currents from satellite within the framework of OSCAR. We summarize the methodology associated with OSCAR, particularly emphasizing the respective contributions of satellite altimeter and scatterometer data to the diagnostic calculations of surface currents. Additionally, we show how the methodology is extended from the tropics, where it was initially developed, to the mid and high latitudes. Finally, we underline the near real-time characteristic of the space- based monitoring of the ocean currents and their validation. This would not be possible without the continuous and on-going satellite coverage of the ocean surface height and winds. Concomitant with the present and future altimetry missions, the OSCAR web site and data server will continue to be updated and will provide an account of any extreme surface current change occurring in the global ocean.

Bonjean, F.; Lagerloef, G.; Johnson, E.; Gunn, J.; Miller, L.; Legeckis, Mitchum, G.; Soreide, N.; Bourassa, M.

2006-07-01

285

Exploring the mental space of autonomous intentional agents.  

PubMed

The ability to infer the intentions of other agents on the basis of their motion is a critical psychological faculty. In the present study, we examine a key question underlying this process, namely: What are the psychologically natural categories of intentional agents and actions? To investigate this question empirically, we use displays containing a number of autonomous, independently programmed agents moving about a two-dimensional environment and interacting with one another. Each agent behaves according to its own simple program, controlled by a small number of parameters that define its "personality." We probe participants' impressions of the similarities among the behaviors of the various agents, and then use multidimensional scaling in an attempt to recover the subjective mental space of agent types. An important variable underlying this space turns out to be a parameter that determines how the agent reacts to a nearby agent at one critical distance. A follow-up experiment suggests that variation along this parameter ultimately contributes to modulating a more fundamental perceptual dimension that reflects how "hostile" or "friendly" the agents appear to be. PMID:22006525

Pantelis, Peter C; Feldman, Jacob

2012-01-01

286

Explore! Materials for Sharing Earth and Space Science in Libraries and After-School Programs  

NASA Astrophysics Data System (ADS)

The Lunar and Planetary Institute's Explore! team trains library and after-school program staff through workshops and Web casts, to engage families and children in their communities in Earth and space science through hands-on actvities.

Nelson, B.; Shipp, S.

2008-03-01

287

Progress on the Development of a Thin Section Sample Preparation Device for Space Exploration  

Microsoft Academic Search

Progress toward the development of a automated rock thin section device for space exploration is presented, supported by PIDDP funding. Progress on rock requirements, rough cutting, and sample grinding\\/polishing is shown.

C. B. Dreyer; K. Zacny; J. Skok; J. Steele; G. Paulsen; M. Nakagawa; J. Schwendeman; E. Carroll

2008-01-01

288

Advanced Analytical Instrument Facility for Analysis of Return Samples from NASA Space Exploration Missions  

NASA Astrophysics Data System (ADS)

A new mass spectrometer with laser post-ionization of neutral species constructed at Argonne National Lab is well suited for analyses of return samples from NASA space exploration missions because of its high useful yield and analytical resolutions.

Veryovkin, I. V.; Calaway, W. F.; Tripa, C. E.; Pellin, M. J.

2006-03-01

289

A multi-objective stochastic approach to combinatorial technology space exploration  

NASA Astrophysics Data System (ADS)

Historically, aerospace development programs have frequently been marked by performance shortfalls, cost growth, and schedule slippage. New technologies included in systems are considered to be one of the major sources of this programmatic risk. Decisions regarding the choice of technologies to include in a design are therefore crucial for a successful development program. This problem of technology selection is a challenging exercise in multi-objective decision making. The complexity of this selection problem is compounded by the geometric growth of the combinatorial space with the number of technologies being considered and the uncertainties inherent in the knowledge of the technological attributes. These problems are not typically addressed in the selection methods employed in common practice. Consequently, a method is desired to aid the selection of technologies for complex systems design with consideration of the combinatorial complexity, multi-dimensionality, and the presence of uncertainties. Several categories of techniques are explored to address the shortcomings of current approaches and to realize the goal of an efficient and effective combinatorial technology space exploration method. For the multi-objective decision making, a posteriori preference articulation is implemented. To realize this, a stochastic algorithm for Pareto optimization is formulated based on the concepts of SPEA2. Techniques to address the uncertain nature of technology impact on the system are also examined. Monte Carlo simulations using the surrogate models are used for uncertainty quantification. The concepts of graph theory are used for modeling and analyzing compatibility constraints among technologies and assessing their impact on the technology combinatorial space. The overall decision making approach is enabled by the application of an uncertainty quantification technique under the framework of an efficient probabilistic Pareto optimization algorithm. As a result, multiple Pareto hyper-surfaces are obtained in a multi-dimensional objective space. Each hypersurface represents a specified probability level, which in turn enables probabilistic comparison of various options. Other more traditional technology selection and scanning techniques such as the greedy algorithm, one-on one-off technique and designs of experiments are also explored. An advisor to recommend the best selection technique from amongst these options based on the complexity and scope of the problem is also an important contribution of this research. Various techniques used for creating the exploration and decision making methodology are experimented on a benchmark knapsack problem. These techniques are used in a synergistic manner to formulate the Pareto Optimization and Selection of Technologies (POST) methodology. POST is implemented on an example technology exploration and selection problem for a 300 passenger commercial aircraft. This is a large problem with 29 technologies, 11 objectives and 4 constraints. Initially, the technologies and their system impacts are defined along with their uncertainties. The computational complexity is evaluated and the problem dimensionality reduced using a dominance structure preserving approach. Probabilistic Pareto optimization is implemented with the reduced dimensionality and three Pareto layers each corresponding to a predefined probability level are created. These Pareto layers are exported to a visualization and analysis environment enabled by JMPRTM. The technology combinations on these Pareto layers are explored using various visualization tools and one combination is selected. The main outcome of this research is a method based on a consistent analytical foundation to create a dynamic tradeoff environment in which decision makers can interactively explore and select technology combinations.

Patel, Chirag B.

290

Towards AN Integrated Scientific and Social Case for Human Space Exploration  

NASA Astrophysics Data System (ADS)

I will argue that an ambitious programme of human space exploration, involving a return to the Moon, and eventually human missions to Mars, will add greatly to human knowledge. Gathering such knowledge is the primary aim of science, but science’s compartmentalisation into isolated academic disciplines tends to obscure the overall strength of the scientific case. Any consideration of the scientific arguments for human space exploration must therefore take a holistic view, and integrate the potential benefits over the entire spectrum of human knowledge. Moreover, science is only one thread in a much larger overall case for human space exploration. Other threads include economic, industrial, educational, geopolitical and cultural benefits. Any responsibly formulated public space policy must weigh all of these factors before deciding whether or not an investment in human space activities is scientifically and socially desirable.

Crawford, I. A.

2004-06-01

291

Rights Spaces: An Exploration of Feminist Approaches to Refugee Law  

Microsoft Academic Search

The exigent needs of refugee women necessitate feminist attempts to use legal mechanisms, however imperfect, to their benefit. However, the temptation to overestimate the importance of feminist gains in this realm must be avoided due to current constraints within the international refugee regime. Most forcibly displaced persons never reach the borders of western countries to claim asylum. Moreover, western 'refugee-receiving'

Natalie Oswin

2001-01-01

292

Tubes of Magnetic Flux and Electric Current in Space Physics  

NASA Astrophysics Data System (ADS)

The singularities of an irrotational magnetic field are lines of electric current. This property derives from the relationship between vector fields and the topology of the underlying three-space and allows for a definition of cosmic field flux tubes and flux ropes as cores (in the sense of the physics of defects) of helical singularities. When applied to force-free flux ropes, and assuming current conservation, an interesting feature is the quantization of the radii, pitches, and helicities. One expects similar quantization effects in the general case. In the special case when the total electric current vanishes, a force-free rope embedded in a medium devoid of magnetic field is nonetheless topologically stable, because it is the core of a singularity of the vector potential. Magnetic merging is also briefly discussed in the same framework.

Kleman, M.; Robbins, J. M.

2013-09-01

293

DesertFD: a finite-domain constraint based tool for design space exploration  

Microsoft Academic Search

As the complexity of computer based systems increases, designers are faced with the task of balancing a variety of design\\u000a choices and parameters against conflicting optimization criteria. Design space exploration seeks to automate or partially\\u000a automate the process of evaluating tradeoff decisions at design time. DesertFD is a domain-independent design space exploration\\u000a tool which facilitates the representation and pruning of

Brandon K. Eames; Sandeep K. Neema; Rohit Saraswat

2010-01-01

294

Exploring the parameter space of the Green-Ampt model  

NASA Astrophysics Data System (ADS)

This study systematically investigates the entire parameter space of the Green-Ampt model for water infiltration and allows for arbitrary constant hydraulic head boundary conditions, any column inclination, hydrophilic and hydrophobic porous media, and a nonzero initial cumulative infiltration. There are five infiltration and five liquid-withdrawal scenarios which differ with respect to the direction of flow and the sign of the acceleration of the liquid. We present analytical solutions for these flow scenarios and 2D phase diagrams that show which flow scenario is predicted depending on the model parameters. All liquid infiltration scenarios, except accelerating downward infiltration (ADI), have already been reported by Green and Ampt. For liquid withdrawal, however, only decelerating downward flow has previously been reported, which is representative of drainage to the water table. We present experimental evidence that ADI may occur in hydrophobic media.

Hilpert, Markus; Glantz, Roland

2013-03-01

295

SEAFLOOR EXPLORATION AND CHARACTERIZATION: PREREQUISITE TO OCEAN SPACE UTILIZATION.  

USGS Publications Warehouse

A historical survey of US bathymetric mapping is presented up through the major mapping project begun in response to the 1983, establishment of an Exclusive Economic Zone (EEZ), 200 nautical miles seaward. The EEZ extends sovereign rights for the purposes of exploring, exploiting, conserving, and managing natural resources in the coastal ocean. This new area is approximately 3. 4 million square nautical miles or about 1. 3 times the total US land area. To characterize the resources within it, the US National Oceanic and Atmospheric Administration (NOAA) and the US Geological Survey (USGS) are undertaking systematic mapping programs of the EEZ. NOAA's effort includes detailed bathymetric mapping of the seabed. The USGS is using a wide-swath side-scan sonar system to map the EEZ seafloor on a reconaissance scale.

Hill, Gary; Lockwood, Millington

1987-01-01

296

Iridium satellites help map electrical currents in space  

NASA Astrophysics Data System (ADS)

The satellite constellation of Iridium LLC, which filed for Chapter 11 bankruptcy in 1999 after it failed to win enough business for its commercial satellite communications services, is still orbiting at an altitude of about 780 kilometers. Now, however, the satellites are helping to write a new chapter in understanding space weather.Magnetometers onboard each of the system's 66 polar-orbiting satellites are working in conjunction with the high-frequency, multinational Super Dual Auroral Radar Network, or SuperDARN, to provide the first continuous measurements of electrical currents between Earth's upper atmosphere and space. These tools also are generating the first global maps of electrical power flowing into the polar upper atmosphere.

Showstack, Randy

297

Current Status and Perspectives of the Space Stations Program: Europe  

NASA Astrophysics Data System (ADS)

Europe became formally Partner of the International Space Station Programme together with Japan and ISS In-Orbit Configuration - April 2002 Canada in 1988 through the signature of the Intergovernmental Agreement following an invitation by US President Reagan to join Programme. In 1993 Russia joined the partnership and the International Partners adopted the current ISS configuration. The International Space Station is today reality with more than 16 assembly flights completed and more than 1/3 of the ISS infrastructure already assembled in orbit. The first European elements operate in-orbit and some early utilisation projects have been successfully completed. The transition from the ISS development to utilisation phase has started. More than 250 future European ISS utilisation projects are today (June 2002) in preparation and an utilisation plan of the European Columbus laboratory, which will be connected to ISS in October 2004, has been established for its first 3 years in orbit. ISS. Achievements of these past Astronauts missions andColumbus Integration at ASTRIUM plans for future missions are summarised. The implementation of the cooperative International Space Station programme is based on the principle of `no exchange of funds between the Partners'. Following this principle ESA has concluded barter agreements with the Partner Agencies to obtain ISS services from the International Partners, in particular the launch of Columbus by the American Space Shuttle, in return for development of elements for the International Partners including infrastructure elements and laboratory support equipment. The paper summarises the current implementation status of existing barter and cooperation agreements and provides an outlook on future cooperation opportunities. With the development of ISS nearing its completion and the demand for its utilisation increasing, Europe is preparing for the future evolution of ISS. The paper presents Europe's vision for future ISS utilisation scenarios and resulting requirements for improved and new ISS services and infrastructure elements.

Feustel-Büechl, J.

2002-01-01

298

Current NASA studies for a Far Ultraviolent Spectrographic Explorer (FUSE)  

NASA Astrophysics Data System (ADS)

The NASA plans for FUSE, a satellite which obtains spectra with resolutions between 100,000 and 100 in the spectral regions from 912 to 1216A and 100 to 912A, are outlined. Scientific problems which can be tackled by FUSE, but not by IUE or the Space Telescope, are discussed. A grazing incidence echelle and a hybrid echelle design are presented. They have high throughput, large simultaneous spectral range, and low background photon counting statistics. The satellite operational organization is similar to that of IUE.

Linsky, J.; Boggess, A.; Bowyer, S.; Caldwell, J.; Cash, W.; Cohen, J.; Dupree, A.; Green, R.; Jenkins, E.; Jura, M.; Leckrone, D.; Moos, H. W.; Savage, B.; Shull, M.; Snow, T.; Timothy, J. G.; Weiler, E.; York, D.

1982-06-01

299

The Strategy Hypercube: Exploring Strategy Space Using Agent-Based Models  

Microsoft Academic Search

We demonstrate a method of representing a firm's strategy as its po- sition and movement within an n-dimensional strategy space. We explore this space through the use of an agent-based model and provide preliminary results as to the appropriateness of different strategies under differing levels of envi- ronmental turbulence.

Duncan A. Robertson

2003-01-01

300

Novel Rock Detection Intelligence for Space Exploration Based on Non-Symbolic Algorithms and Concepts  

Microsoft Academic Search

Future space exploration can utilize artificial intelligence as an integral part of next generation space rover technology to make the rovers more autonomous in performing mission objectives. The main advantage of the increased autonomy through a higher degree of intelligence is that it allows for greater utilization of rover resources by reducing the frequency of time consuming communications between rover

Sule Yildirim; Ronald L. Beachell; Henning Veflingstad

2007-01-01

301

The application of nuclear power and propulsion for space exploration missions  

Microsoft Academic Search

An approach to integrating nuclear technology into space exploration missions is advanced that is based on conditioning nuclear technology to be broadly applicable across the existing mission set. Two similar baselines are presented for small nuclear thermal rocket (NTR) engines for exploration missions. Small NTR engines are also examined in terms of their use in manned Mars missions, and the

Robert M. Zubrin; Tal K. Sulmeisters

1992-01-01

302

Technology assessment in support of the presidential vision for space exploration  

Microsoft Academic Search

This paper discusses the process and results of technology assessment in support of the United States vision for space exploration of the Moon, Mars and beyond. The paper begins by reviewing the presidential vision: a major endeavor in building systems of systems. It discusses why we wish to return to the Moon, and the exploration architecture for getting there safely,

Charles R. Weisbin; William Lincoln; Joe Mrozinski; Hook Hua; Sofia Merida; Kacie Shelton; Virgil Adumitroaie; Jason Derleth; Robert Silberg

2006-01-01

303

The exploration about the means of lunar-landing based on space-launch  

Microsoft Academic Search

The lunar exploration and lunar-landing is the first step of china s deep space exploration On the basement of our country s achievements and the experiences of the foreign countries the paper brings forward the idea that use the existing transportation technology to sent the Launch vehicles and cosmonauts to the near-earth orbit in batches assemble the components together on

Jiang Yi; Zhang Zheming; Fu Debin

2006-01-01

304

Space Nuclear Power and Propulsion - a basic Tool for the manned Exploration of the Solar System  

Microsoft Academic Search

Humanity has started to explore space more than 40 years ago. Numerous spacecraft have left the Earth in this endeavour, but while unmanned spacecraft were already sent out on missions, where they would eventually reach the outer limits of the Solar System, manned exploration has always been confined to the tiny bubble of the Earth's gravitational well, stretching out at

Norbert Frischauf

2004-01-01

305

Exploring the limits of critical currents in superconductors  

NASA Astrophysics Data System (ADS)

Mechanisms, which determine the ultimate limit of the critical current density Jc(T,B) in superconductors are discussed. The talk is mostly focused on the extreme strong pinning limit of highly deformed vortex segments, the role of anisotropy, current-blocking effects of pinning centers and grain boundaries, thermal fluctuations of vortices in high-Tc superconductors. In particular, the design of optimum pinning nanostructures, which produce the maximum Jc is addressed. The results are applied to YBCO thick-film coated conductors with insulating nanoprecipitates, for which several groups have reported very high Jc values, up to 12-20 % of the depairing current density. Requirements for a putative room-temperature superconductor to be useful in high-field applications are discussed.

Gurevich, Alex

2008-03-01

306

Exploring Current Issues through the Hot Topics Poster  

ERIC Educational Resources Information Center

|This paper describes a research paper and poster assignment used in an undergraduate leisure and human behavior course. The intent of this learning activity is to increase student knowledge of current issues within the industry as well as to enhance students' professional communication skills. A description of the assignment is shared along with…

Nisbett, Nancy

2012-01-01

307

Development of Advanced Stirling Radioisotope Generator for Space Exploration  

NASA Astrophysics Data System (ADS)

Under the joint sponsorship of the Department of Energy and NASA, a radioisotope power system utilizing Stirling power conversion technology is being developed for potential future space missions. The higher conversion efficiency of the Stirling cycle compared with that of Radioisotope Thermoelectric Generators (RTGs) used in previous missions (Viking, Pioneer, Voyager, Galileo, Ulysses, Cassini, and New Horizons) offers the advantage of a four-fold reduction in PuO2 fuel, thereby saving cost and reducing radiation exposure to support personnel. With the advancement of state-of-the-art Stirling technology development under the NASA Research Announcement (NRA) project, the Stirling Radioisotope Generator program has evolved to incorporate the advanced Stirling convertor (ASC), provided by Sunpower, into an engineering unit. Due to the reduced envelope and lighter mass of the ASC compared to the previous Stirling convertor, the specific power of the flight generator is projected to increase from 3.5 We/kg to 7 We/kg, along with a 25% reduction in generator length. Modifications are being made to the ASC design to incorporate features for thermal, mechanical, and electrical integration with the engineering unit. These include the heat collector for hot end interface, cold-side flange for waste heat removal and structural attachment, and piston position sensor for ASC control and power factor correction. A single-fault tolerant, active power factor correction controller is used to synchronize the Stirling convertors, condition the electrical power from AC to DC, and to control the ASCs to maintain operation within temperature and piston stroke limits. Development activities at Sunpower and NASA Glenn Research Center (GRC) are also being conducted on the ASC to demonstrate the capability for long life, high reliability, and flight qualification needed for use in future missions.

Chan, Jack; Wood, J. Gary; Schreiber, Jeffrey G.

2007-01-01

308

Geodiversity: Exploration of 3D geological model space  

NASA Astrophysics Data System (ADS)

The process of building a 3D model necessitates the reconciliation of field observations, geophysical interpretation, geological data uncertainty and the prevailing tectonic evolution hypotheses and interpretations. Uncertainty is compounded when clustered data points collected at local scales are statistically upscaled to one or two points for use in regional models. Interpretation is required to interpolate between sparse field data points using ambiguous geophysical data in covered terranes. It becomes clear that multiple interpretations are possible during model construction. The various interpretations are considered as potential natural representatives, but pragmatism typically dictates that just a single interpretation is offered by the modelling process. Uncertainties are introduced into the 3D model during construction from a variety of sources and through data set optimisation that produces a single model. Practices such as these are likely to result in a model that does not adequately represent the target geology.A set of geometrical 'geodiversity' metrics are used to analyse a 3D model of the Gippsland Basin, southeastern Australia after perturbing geological input data via uncertainty simulation. The resulting sets of perturbed geological observations are used to calculate a suite of geological 3D models that display a range of geological architectures. The concept of biodiversity has been adapted for the geosciences to quantify geometric variability, or geodiversity, between models in order to understand the effect uncertainty has models geometry. Various geometrical relationships (depth, volume, contact surface area, curvature and geological complexity) are used to describe the range of possibilities exhibited throughout the model suite. End-member models geodiversity metrics are classified in a similar manner to taxonomic descriptions. Further analysis of the model suite is performed using principal component analysis (PCA) to determine important geometrical characteristics. The configuration of the model space is determined through identifying 'outlier' model examples, which potentially represent undiscovered model 'species'.

Lindsay, M. D.; Jessell, M. W.; Ailleres, L.; Perrouty, S.; de Kemp, E.; Betts, P. G.

2013-05-01

309

From Ground to Space: A Roadmap with Robotic & Exploration Elements  

NASA Astrophysics Data System (ADS)

Ground-based 21 cm cosmology and astrophysics measurements are underway, with initial limits on the H I signal at various redshifts established. The Moon is a unique platform for 21 cm cosmology and astrophysics because its farside is shielded from intense terrestrial emissions and its ionosphere is significantly less dense than Earth's. There is international interest in returning humans to the Moon, with instrument packages and telescopes deployed as part of Exploration activities. A roadmap for the staged deployment of lunar telescopes is Stage I: On-going ground-based activities to develop the instruments and techniques, as well as detect or place austere limits on the redshifted H I 21 cm line. Stage IIa: One antenna (or a few) on a lunar orbiter. The prime science is to detect the sky-averaged, redshifted H I 21 cm line that is excited by the UV and X-ray fields of the first stars and accreting black holes. Stage IIb: One antenna (or a few) on the lunar surface. A near-side antenna would monitor the lunar ionosphere and track the balance between solar wind-induced effects and lunar interior outgassing; a far-side antenna would study the redshifted 21 cm line. Deployment could be done either during astronaut sorties or telerobotically. This stage could occur in parallel with Stage IIa. Stage III: A near-side telescope capable of studying particle acceleration within the inner heliosphere ( 100 antennas distributed over 1 km). Such a telescope could detect the magnetically-generated emissions from solar system planets, and potentially from extrasolar planets. Stage IV: A far-side telescope capable of imaging the H I 21 cm line from Cosmic Dawn and into the Dark Ages ( 105 antennas over 10 km). It would also be capable of detecting the magnetospheric emission from extrasolar planets.

Lazio, T. Joseph W.; Bowman, J.; Burns, J.; Farrell, W.; Jones, D.; Kasper, J.; Stewart, K.; Weiler, K.

2012-05-01

310

Alien Genetic Algorithm for Exploration of Search Space  

NASA Astrophysics Data System (ADS)

Genetic Algorithm (GA) is a widely accepted population based stochastic optimization technique used for single and multi objective optimization problems. Various versions of modifications in GA have been proposed in last three decades mainly addressing two issues, namely increasing convergence rate and increasing probability of global minima. While both these. While addressing the first issue, GA tends to converge to a local optima and addressing the second issue corresponds the large computational efforts. Thus, to reduce the contradictory effects of these two aspects, we propose a modification in GA by adding an alien member in the population at every generation. Addition of an Alien member in the current population at every generation increases the probability of obtaining global minima at the same time maintaining higher convergence rate. With two test cases, we have demonstrated the efficacy of the proposed GA by comparing with the conventional GA.

Patel, Narendra; Padhiyar, Nitin

2010-10-01

311

ESSC-ESF Position Paper-Science-Driven Scenario for Space Exploration: Report from the European Space Sciences Committee (ESSC)  

Microsoft Academic Search

In 2005 the then ESA Directorate for Human Spaceflight, Microgravity and Exploration (D-HME) commissioned a study from the European Science Foundation's (ESF) European Space Sciences Committee (ESSC) to examine the science aspects of the Aurora Programme in preparation for the December 2005 Ministerial Conference of ESA Member States, held in Berlin. A first interim report was presented to ESA at

Jean-Claude Worms; Helmut Lammer; Antonella Barucci; Reta Beebe; Jean-Pierre Bibring; Jacques Blamont; Michel Blanc; Roger Bonnet; John R. Brucato; Eric Chassefière; Angioletta Coradini; Ian Crawford; Pascale Ehrenfreund; Heino Falcke; Rupert Gerzer; Monica Grady; Manuel Grande; Gerhard Haerendel; Gerda Horneck; Bernhard Koch; Andreï Lobanov; José J. Lopez-Moreno; Robert Marco; Peter Norsk; Dave Rothery; Jean-Pierre Swings; Cam Tropea; Stephan Ulamec; Frances Westall; John Zarnecki

2009-01-01

312

14 CFR 1266.104 - Cross-waiver of liability for launch agreements for science or space exploration activities...  

Code of Federal Regulations, 2010 CFR

14 Aeronautics and Space 5 2010-01-01 2010-01-01 false...of liability for launch agreements for science or space exploration activities unrelated to the International Space Station. 1266.104 Section 1266.104...

2010-01-01

313

Private equity investments beyond Earth orbits: Can space exploration be the new frontier for private investments?  

NASA Astrophysics Data System (ADS)

The year 2004 can be considered an important milestone for space activities. First, on January 14, 2004 President Bush announced a new vision for human and robotic space exploration named “A Renewed Spirit of Discovery”. This new space exploration policy called for “a sustained and affordable human and robotic program to explore the solar system and beyond” and seeks also to “promote international and commercial participation in space exploration to further US scientific, security, and economic interests”. Secondly, the satellite industry has experienced a trend of private investment fund acquisitions. Five of six major fixed and mobile satellite service providers in the world have been partly or entirely sold to conventional financial investors. These transactions have taken place despite the background noise of overcapacity, stagnant growth and declining operating margins satellite services sector. Over the last 18 months, we have seen a total of approximately US $12B dollars in private equity transactions in the satellite sector. Finally, the Ansari X prize has been won opening the possibility of the personal spaceflight revolution. This paper seeks to provide some insights into the nature, timing and a rationale for these investments in the space sector. Then, an attempt is made to analyze the potential that space exploration might present for traditional financial investors.

Mathurin, Jeph; Peter, Nicolas

2006-07-01

314

Accessing the Moon: Engaging Diverse Audiences in Current and Future Lunar Exploration  

NASA Astrophysics Data System (ADS)

A new age of lunar exploration and discovery is dawning that will require participation by the next generations of students and active engagement of the general public. In recent years, the Lunar and Planetary Institute (LPI) has engaged diverse audiences - classroom teachers, librarians and after school program providers, the general public - in learning about lunar science and exploration, often in collaboration with lunar mission E/PO teams, such as the Lunar Reconnaissance Orbiter and the Moon Mineralogy Mapper instrument on Chandrayaan-1, and with Johnson Space Center's Astromaterials Research and Exploration Science education team. In the process, LPI has developed a suite of lunar educational programs and products, including week-long lunar educator institutes, curriculum materials, library programs, classroom poster sets, and distance learning courses, The large variety of resources, powerpoints, posters, activities, and more are now freely available to both educators and to the general public to download and use, at www.lpi.usra.edu/education/moon . The week-long Earth-Moon Institute for Teachers grades 5-8 provided a mechanism for sharing a broad variety of content, activities, and pedagogy on the Moon. Much of the Institute focused on hands-on inquiry based age-appropriate activities. Modeling and discussion encompassed research about best practices for facilitating student learning on specific topics and strategies for uncovering and addressing student misconceptions. The participants conducted related, integrated, inquiry projects, in which inquiry was explicitly discussed to support participants in their future implementation. This poster will share:

  • the variety of lunar resources and programs developed by LPI
  • mechanisms for their use
  • audience reactions to lunar science and exploration so far
  • details about programs that can be adapted at other sites, such as the week-long institute
  • and new programs currently underway.

Shupla, Christine; Shipp, S.

2009-01-01

315

Grid-based Exploration of Cosmological Parameter Space with Snake  

NASA Astrophysics Data System (ADS)

We present a fully parallelized grid-based parameter estimation algorithm for investigating multidimensional likelihoods called Snake, and apply it to cosmological parameter estimation. The basic idea is to map out the likelihood grid-cell by grid-cell according to decreasing likelihood, and stop when a certain threshold has been reached. This approach improves vastly on the "curse of dimensionality" problem plaguing standard grid-based parameter estimation simply by disregarding grid cells with negligible likelihood. The main advantages of this method compared to standard Metropolis-Hastings Markov Chain Monte Carlo methods include (1) trivial extraction of arbitrary conditional distributions; (2) direct access to Bayesian evidences; (3) better sampling of the tails of the distribution; and (4) nearly perfect parallelization scaling. The main disadvantage is, as in the case of brute-force grid-based evaluation, a dependency on the number of parameters, N par. One of the main goals of the present paper is to determine how large N par can be, while still maintaining reasonable computational efficiency; we find that N par = 12 is well within the capabilities of the method. The performance of the code is tested by comparing cosmological parameters estimated using Snake and the WMAP-7 data with those obtained using CosmoMC, the current standard code in the field. We find fully consistent results, with similar computational expenses, but shorter wall time due to the perfect parallelization scheme.

Mikkelsen, K.; Næss, S. K.; Eriksen, H. K.

2013-11-01

316

On the Organisation of World Ships and Other Gigascale Interstellar Space Exploration Projects  

NASA Astrophysics Data System (ADS)

The development and deployment of world ships or other feats of interstellar exploration will without doubt require orders of magnitude more resources than needed for current or past megaprojects (Apollo, Iter, LHC,...). Question is how enough resources for such gigaprojects can be found in a scenario assuming limited, moderate economic growth throughout the next centuries, i.e. without human population and productivity continuing to grow exponentially, and without extreme events such as economic collapse or singularity.Three defining features of gigascale space projects are identified, which should be recognized to the fullest: their almost absolute nonprofit character, their massive cost in terms of time and resources and their non-urgency leading to procrastina- tion. It will be argued that the best chance of getting a world ship or another interstellar project started in this generation is to establish an international network of non governmental organizations (NGOs) focused on private and public fundraising for interstellar exploration and supporting a bottom-up societal movement, similar to e.g. the WWF. It will be shown that this path can reduce the massive barriers to entry as well as the level of governmental support needed.

Ceyssens, F.; Driesen, M.; Wouters, K.

317

The Space Science Suitcase—Instruments for Exploring Near-Earth Space from the Classroom  

NASA Astrophysics Data System (ADS)

The aurora and other phenomena in near Earth space are becoming a considerable part of the science curriculum in upper secondary school (high school) in Norway. Introducing scientific methods to the young students is an important objective of the education, but experimental experience is mainly restricted to simple laboratory exercises under controlled conditions; observations of uncontrollable natural phenomena are generally left to academic scientists and researchers. The Space Physics Group and The Science Education and Outreach Group at The Department of Physics and Technology, University of Bergen, are constructing a Space Science Suitcase with a set of simple versions of instruments for monitoring solar and geophysical activity in near Earth space. The instruments will be lent to physics classes in upper secondary schools.

Olafsson, Kjartan; Ostgaard, Nikolai; Tanskanen, Eija

2009-04-01

318

Phase Space Exploration of Acetylene at Energies up to 13,000 Cm-1  

NASA Astrophysics Data System (ADS)

The rotation-vibration Hamiltonian of acetylene is known in detail up to 13,000 Cm-1 in the electronic ground state, allows the calculation of time-dependent dynamics for postulated excitations of certain bright states. Three different measures of phase space exploration are examined including the participation number, Gruebele's dispersion, and the Shannon entropy. The time scales for phase space exploration span the range from 20 fs to 10 ps. The volume of phase space explored by the dynamics increases with energy and the rotational quantum number, J reaching about 90% of the (GOE) statistical limit at 12,000 Cm-1 and J = 100. At low and intermediate J, the extent of phase space exploration is reduced for the local bender and counter-rotator bright states as compared to their normal mode counterparts. However, the phase space exploration of the local mode CH stretch state is similar to that of the corresponding normal mode vibration. These calculations shed light on the applicability of the energy randomization assumption that is at the heart of the Rice-Rampsberger-Kassel-Marcus (RRKM) theory of unimolecular reactions.

Perry, David S.; Martens, Jonathan; Herman, Michel; Amyay, Badr

2011-06-01

319

Novel Rock Detection Intelligence for Space Exploration Based on Non-Symbolic Algorithms and Concepts  

NASA Astrophysics Data System (ADS)

Future space exploration can utilize artificial intelligence as an integral part of next generation space rover technology to make the rovers more autonomous in performing mission objectives. The main advantage of the increased autonomy through a higher degree of intelligence is that it allows for greater utilization of rover resources by reducing the frequency of time consuming communications between rover and earth. In this paper, we propose a space exploration application of our research on a non-symbolic algorithm and concepts model. This model is based on one of the most recent approaches of cognitive science and artificial intelligence research, a parallel distributed processing approach. We use the Mars rovers. Sprit and Opportunity, as a starting point for proposing what rovers in the future could do if the presented model of non-symbolic algorithms and concepts is embedded in a future space rover. The chosen space exploration application for this paper, novel rock detection, is only one of many potential space exploration applications which can be optimized (through reduction of the frequency of rover-earth communications. collection and transmission of only data that is distinctive/novel) through the use of artificial intelligence technology compared to existing approaches.

Yildirim, Sule; Beachell, Ronald L.; Veflingstad, Henning

2007-01-01

320

Development of a thin section device for space exploration: Overview and system performance estimates  

NASA Astrophysics Data System (ADS)

In this paper we present a conceptual design of a spaceborne instrument for the in situ production of rock thin sections on planetary surfaces. The in situ Automated Rock Thin Section Instrument (IS-ARTS) conceptual design demonstrates that the in situ production of thin sections on a planetary body is a plausible new instrument capability for future planetary exploration. Thin section analysis would reduce much ambiguity in the geological history of a sampled site that is present with instruments currently flown. The technical challenge of producing a thin section device compatible with the spacecraft environment is formidable and has been thought too technically difficult to be practical. Terrestrial thin section preparation requires a skilled petrographist, several preparation instruments that individually exceed typical spacecraft mass and power limits, and consumable materials that are not easily compatible with spaceflight. In two companion papers we present research and development work used to constrain the capabilities of IS-ARTS in the technical space compatible with the spacecraft environment. For the design configuration shown we conclude that a device can be constructed that is capable of 50 sample preparations over a 2 year lifespan with mass, power, and volume constraints compatible with current landed Mars mission configurations. The technical requirements of IS-ARTS (mass, power and number of samples produced) depend strongly on the sample mechanical properties, sample processing rate, the sample size and number of samples to be produced.

Dreyer, Christopher B.; Zacny, Kris; Steele, John P. H.; Schwendeman, James R.; Paulsen, Gale; Andersen, Robert C.; Skok, John

2013-05-01

321

ESRO and the Deep Space - European Planetary Exploration Planning Before ESA  

NASA Astrophysics Data System (ADS)

In the 1960s and early 1970s the United States and the Soviet Union were racing each other in the “space race” whose main arena were piloted spaceflight, and in particular Moon missions, and, to a lesser extent, planetary exploration. During the same timeframe, several European states were trying to cooperate in the scientific exploration of space and in the design of space launchers. Undaunted by many difficulties, including the late start of the European space program, at least when compared with the efforts of the US and USSR, the relative lack of “world class” planetary scientists in Europe and the fear to duplicate the results of the two superpowers, European space planners prepared several studies of deep space missions. In the end, none of the European projects came to fruition, although some of these studies paved the way for successful missions such as Giotto and Ulysses. At the same time, some European countries elected to participate to the planetary exploration programs of the superpowers, thus maturing experiences that would turn out to be useful when European deep space missions finally took off in the 1980s.

Ulivi, P.

322

Space-charge-limited currents in polyimide films  

NASA Astrophysics Data System (ADS)

Space-charge-limited currents have been identified in thin polyimide film capacitor structures as the main conduction process in the very high temperature range from 320 °C to 400 °C before the breakdown. The transition field between the trap-filled-limit conduction and the trap-free conduction is reported versus temperature. Assuming an exponential distribution of the traps in the forbidden gap, both the characteristic temperature and trap energy are obtained at 446 °C and 62 meV, respectively. The total trap density is accurately estimated at 1.5 × 1017 cm-3 using the Kumar approximation [Kumar et al., J. Appl. Phys. 94, 1283 (2003)]. Finally, the mobility temperature dependence of free charges is reported between 1.6 × 10-6 and 2.3 × 10-6 cm2 V-1 s-1 in the range from 340 °C to 400 °C.

Diaham, Sombel; Locatelli, Marie-Laure

2012-12-01

323

Current views and future programs in cardiovascular physiology in space  

NASA Astrophysics Data System (ADS)

The volume shift of 2000 cm 3 from the lower to the upper part of the human body during weightlessness gave rise to theoretical and practical questions which are addressed in this communication. The analysis revealed that the mobilized fluid reduced the interstitial fluid of the lower extremities by 40%. Applying the current ideas in the field of interstitial tissue physiology to these problems, one must conclude that the fluid displacement can only be brought about by a change of the interstitial tissue compliance. Based on the observations made by the astronauts and on our working hypothesis, a method was proposed to follow the fluid migration and to measure the tissue compliance in man. Results are reported from experiments under terrestrial conditions. They show that the tissue compliance indeed can be modulated. Applying the method in space can eventually help to clarify several concepts in terrestrial physiology.

Kirsch, K. A.; Von Ameln, H.

324

The Space Science Suitcase - Instruments for Exploring Space Weather From the Classroom  

NASA Astrophysics Data System (ADS)

The aurora and other phenomena in near Earth space are becoming a considerable part of the science curriculum in upper secondary school (high school - age 16 to 19) in Norway. Introducing scientific methods to the young students is an important task of the education, but experimental science experience is to a great extent restricted to simple laboratory exercises under controlled conditions; observations of uncontrollable natural phenomena are generally left to academic scientists and researchers. The Space Physics Group and The Science Education and Outreach Group at The Department of Physics and Technology, University of Bergen, have constructed a "Space Science Suitcase" with a set of simple versions of instruments for monitoring solar and geophysical activity in near Earth space. The contents of the suitcase are: Two solar telescopes, commercial SLR digital camera with a fisheye lens for photographing the aurora, tri-axial magnetometer, Geiger counter, two spectroscopes, GPS-receiver, a laptop for collecting the pictures and measurements, and a manual with suggestions for some relevant experiments. The suitcase is lent to physics classes in upper secondary schools for 3-4 weeks at each school, allowing the students to do their own quantitative observations of sunspots, magnetic disturbances, optical aurora, background radiation etc. Comparison of these observations with online observations from ground based observatories and satellites is an integrated part of the project. The purpose of the experiment is to promote scientific literacy, bring excitement about space phenomena into the classroom, and, finally, to recruit enthusiastic students to university studies in physic and geophysics in general, and space science in particular.

Olafsson, K.; Ostgaard, N.

2008-12-01

325

Design of high performance management and control system of nano-satellite for distributed space exploration  

NASA Astrophysics Data System (ADS)

Nano-satellite is a kind of advanced and effective tool for space exploration. And the nano-satellite formation flight technology becomes more and more important in distributed space exploration. Thus a design of high performance management and control system (named MCS) of nano-satellite for formation space exploration is presented in this paper. Different with traditional design concept for satellites, MCS adopts a modular configuration not only to satisfy composite requirements of processing capacity, integration, cost and power of nano-satellite, but also to fit applications in formation flight experimentation. MCS includes OBC (on-board computer) module, attitude & orbit control module, telemetry & telecommand module, and power management module. Furthermore, as core component the design uses reconfiguration scheme and COTS (commercial-off-the-shelf) technology, so it shows an outstanding performance in high efficiency, high reliability, low power and low cost for satellite engineering applications.

Sun, Ke; Fang, Jiancheng; Zhu, Zhuangsheng; Wei, Xuechao

2008-11-01

326

Ethical Considerations and Planetary Protection for Future Space Exploration - Starting with the Basics  

NASA Astrophysics Data System (ADS)

As COSPAR scientists deliberate what types of frameworks and policy approaches may be applicable to future activities by various sectors in space exploration, it also needs to consider the challenging question of what ethical values and foundations should be used in dealing with life, objects and activities in outer space. A 2010 COSPAR Workshop Report on Ethical Considerations for Planetary Protection in Space Exploration recommended that it is appropriate to maintain the existing PP policy aimed at scientific concerns even as we begin to explore various practical approaches to future contamination avoidance policies. It is also appropriate to examine in parallel the ethical considerations applicable to potential indigenous extraterrestrial life, non-living extraterrestrial features and environments, and planned uses and activities involving diverse life from Earth. Since numerous sectors have begun to propose activities raising varied ethical concerns (e.g., protection and management on the moon, strip mining, space synthetic biology, space code of conduct, and commercial space transport), it is timely to initiate serious international discussions about the appropriate ethical foundations and questions applicable to future space exploration. Plans are underway for convening interdisciplinary work groups to explore and deliberate on the values (e.g., intrinsic and instrumental) and ethical foundations that are appropriate for use in deliberations involving potential indigenous extraterrestrial life and the different classes of target objects and environments in our solar system. More than ever, information on bioethics, environmental ethics and geoethics will provide helpful guidance and foundational approaches of relevance to future policy deliberations that seek to go beyond science protection per se.

Race, Margaret

2012-07-01

327

Modeling international cooperation in human space exploration for the twenty-first century  

NASA Astrophysics Data System (ADS)

The policy process of international cooperation in space exploration, including optimistic and pessimistic scenarios for the twenty-first century, is modeled and examined in this study. In the optimistic scenario, international cooperation involves a balanced and interdependent distribution of capabilities between states, their respective national space agencies and communities of space scientists and space engineers. Cooperation is characterized by interstate participation in critical path components and joint research and development. In the pessimistic scenario, international cooperation is structured and dominated politically and economically by powerful states vis-à-vis weaker states. Cooperation is limited to coordination of separate nationally approved projects and augmentation of capabilities in noncritical path components. On the basis of these two scenarios, policy predictions and implications relevant to exploration missions in the twenty-first century, such as a human-tended lunar base and human missions to Mars, are presented and discussed.

Sadeh, E.; Lester, J. P.; Sadeh, W. Z.

328

Space Elevators: Building a Permanent Bridge for Space Exploration and Economic Development.  

National Technical Information Service (NTIS)

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 s...

D. V. Smitherman

2000-01-01

329

Course Crash in Hybrid Space: An Exploration and Recommendations for Virtual Course Space  

ERIC Educational Resources Information Center

Understanding what hybrid space is, much less understanding what happens in that virtual realm, can raise difficult questions. For example, our campus's question "How do we define hybrid?" has kept us busy and guessing for over a year now. In this article, we offer a few suggestions on how to proceed with hybrid issues, including how to deal with…

Gerard, Joseph G.; Gerard, Reena Lederman; Casile, Maureen

2010-01-01

330

The Space Science Suitcase - Instruments for Exploring Space Weather From the Classroom  

Microsoft Academic Search

The aurora and other phenomena in near Earth space are becoming a considerable part of the science curriculum in upper secondary school (high school - age 16 to 19) in Norway. Introducing scientific methods to the young students is an important task of the education, but experimental science experience is to a great extent restricted to simple laboratory exercises under

K. Olafsson; N. Ostgaard

2008-01-01

331

Course Crash in Hybrid Space: An Exploration and Recommendations for Virtual Course Space  

ERIC Educational Resources Information Center

|Understanding what hybrid space is, much less understanding what happens in that virtual realm, can raise difficult questions. For example, our campus's question "How do we define hybrid?" has kept us busy and guessing for over a year now. In this article, we offer a few suggestions on how to proceed with hybrid issues, including how to deal with…

Gerard, Joseph G.; Gerard, Reena Lederman; Casile, Maureen

2010-01-01

332

Performance/price estimates for cortex-scale hardware: a design space exploration.  

PubMed

In this paper, we revisit the concept of virtualization. Virtualization is useful for understanding and investigating the performance/price and other trade-offs related to the hardware design space. Moreover, it is perhaps the most important aspect of a hardware design space exploration. Such a design space exploration is a necessary part of the study of hardware architectures for large-scale computational models for intelligent computing, including AI, Bayesian, bio-inspired and neural models. A methodical exploration is needed to identify potentially interesting regions in the design space, and to assess the relative performance/price points of these implementations. As an example, in this paper we investigate the performance/price of (digital and mixed-signal) CMOS and hypothetical CMOL (nanogrid) technology based hardware implementations of human cortex-scale spiking neural systems. Through this analysis, and the resulting performance/price points, we demonstrate, in general, the importance of virtualization, and of doing these kinds of design space explorations. The specific results suggest that hybrid nanotechnology such as CMOL is a promising candidate to implement very large-scale spiking neural systems, providing a more efficient utilization of the density and storage benefits of emerging nano-scale technologies. In general, we believe that the study of such hypothetical designs/architectures will guide the neuromorphic hardware community towards building large-scale systems, and help guide research trends in intelligent computing, and computer engineering. PMID:21232918

Zaveri, Mazad S; Hammerstrom, Dan

2010-12-23

333

Explaining public support for space exploration funding in America: A multivariate analysis  

NASA Astrophysics Data System (ADS)

Recent studies have identified the need to understand what shapes public attitudes toward space policy. I address this gap in the literature by developing a multivariate regression model explaining why many Americans support government spending on space exploration. Using pooled data from the 2006 and 2008 General Social Surveys, the study reveals that spending preferences on space exploration are largely apolitical and associated instead with knowledge and opinions about science. In particular, the odds of wanting to increase funding for space exploration are significantly higher for white, male Babyboomers with a higher socio-economic status, a fondness for organized science, and a post-secondary science education. As such, I argue that public support for NASA's spending epitomizes what Launius termed “Apollo Nostalgia” in American culture. That is, Americans benefitting most from the old social order of the 1960s developed a greater fondness for science that makes them more likely to lament the glory days of space exploration. The article concludes with suggestions for how to elaborate on these findings in future studies.

Nadeau, François

2013-05-01

334

EXPLORING TRANSVERSE BEAM STABILITY IN THE SNS IN THE PRESENCE OF SPACE CHARGE.  

SciTech Connect

The highest possible intensity in the machine is typically determined by the onset of coherent beam instabilities. Understanding the contribution of various effects to the damping and growth of such instabilities in the regime of strong space charge is thus of crucial importance. In this paper we explore transverse beam stability by numerical simulations using recently implemented models of transverse impedance and three-dimensional space charge. Results are discussed with application to the SNS accumulators.

FEDOTOV,A.V.; BLASKIEWICZ,M.; WEI,J.; DANILOV,V.; HOLMES,J.; SHISHLO,A.

2002-06-03

335

Impact of the Columbia supercomputer on NASA space and exploration missions  

Microsoft Academic Search

NASA's 10,240-processor Columbia supercomputer gained worldwide recognition in 2004 for increasing the space agency's computing capability ten-fold, and enabling U.S. scientists and engineers to perform significant, breakthrough simulations. Columbia has amply demonstrated its capability to accelerate NASA 's key missions in space operations, exploration systems, science, and aeronautics. Columbia is part of an integrated high-end computing (HEC) environment comprised of

Rupak Biswas; Dochan Kwak; Cetin Kiris; Scott Lawrence

2006-01-01

336

The Space Science Suitcase—Instruments for Exploring Near-Earth Space from the Classroom  

Microsoft Academic Search

The aurora and other phenomena in near Earth space are becoming a considerable part of the science curriculum in upper secondary\\u000a school (high school) in Norway. Introducing scientific methods to the young students is an important objective of the education,\\u000a but experimental experience is mainly restricted to simple laboratory exercises under controlled conditions; observations\\u000a of uncontrollable natural phenomena are generally

Kjartan Olafsson; Nikolai Ostgaard; Eija Tanskanen

2009-01-01

337

Opportunities for Space Science Education Using Current and Future Solar System Missions  

NASA Astrophysics Data System (ADS)

The Education and Public Outreach (E/PO) office in The Johns Hopkins University Applied Physics Laboratory (APL) Space Department strives to excite and inspire the next generation of explorers by creating interactive education experiences. Since 1959, APL engineers and scientists have designed, built, and launched 61 spacecraft and over 150 instruments involved in space science. With the vast array of current and future Solar System exploration missions available, endless opportunities exist for education programs to incorporate the real-world science of these missions. APL currently has numerous education and outreach programs tailored for K-12 formal and informal education, higher education, and general outreach communities. Current programs focus on Solar System exploration missions such as the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), Miniature Radio Frequency (Mini-RF) Moon explorer, the Radiation Belt Storm Probes (RBSP), New Horizons mission to Pluto, and the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) Satellite, to name a few. Education and outreach programs focusing on K-12 formal education include visits to classrooms, summer programs for middle school students, and teacher workshops. APL hosts a Girl Power event and a STEM (Science, Technology, Engineering, and Mathematics) Day each year. Education and outreach specialists hold teacher workshops throughout the year to train educators in using NASA spacecraft science in their lesson plans. High school students from around the U.S. are able to engage in NASA spacecraft science directly by participating in the Mars Exploration Student Data Teams (MESDT) and the Student Principal Investigator Programs. An effort is also made to generate excitement for future missions by focusing on what mysteries will be solved. Higher education programs are used to recruit and train the next generation of scientists and engineers. The NASA/APL Summer Internship Program offers a unique glimpse into the Space Department’s “end-to-end” approach to mission design and execution. College students - both undergraduate and graduate - are recruited from around the U.S. to work with APL scientists and engineers who act as mentors to the students. Many students are put on summer projects that allow them to work with existing spacecraft systems, while others participate in projects that investigate the operational and science objectives of future planned spacecraft systems. In many cases these interns have returned to APL as full-time staff after graduation.

Matiella Novak, M.; Beisser, K.; Butler, L.; Turney, D.

2010-12-01

338

The Acoustic Doppler Current Profiler (adcp) as a Tool for Ocean Exploration  

NASA Astrophysics Data System (ADS)

Although the ADCP has been around for three decades it remains somewhat underappreciated for its excellent exploratory potential in several areas. First and perhaps foremost because oceanographers have always been handicapped in their ability to resolve horizontal patterns below the surface, the ADCP opens up a powerful and very cost-effective window into the ocean water column to explore the meso- and submesoscale velocity field at very high resolution. This is particularly true when ADCP data are collected from just a single instrument mounted on a vessel operating repeatedly over an extended period of time in an area or along a route. The ADCP greatly expands upon hydrographic and XBT information by directly measuring the velocity field accurately without any assumptions about geostrophy or the velocity of reference layers. Second, vessels in transit can characterize currents and eddy activities across contrasting oceanic regimes and highlight their relation to the steering role of bottom topography. Third, even though the ADCP is a single frequency device the backscatter signal recorded by the ADCP is showing considerable skill in revealing space-time patterns of biomass variability. Here, through data we have taken over the past ten years, we survey the ADCP’s future as a tool of exploration across several dimensions: space, time, and parameter (physics and biology). Today, thanks to the ADCP we have a far more accurate picture of the velocity and vorticity structure of fronts and eddies. At the surface a front is simply a transition between different water masses, but the actual transition will often consist a water-mass and potential vorticity jump on a significantly smaller scale within the frontal feature. The same applies to the boundaries of rings and lenses. Commercial vessels equipped with ADCPs operating on a repeat schedule can document underlying patterns that single transects or cruises cannot detect due to inherent eddy activity. Newly discovered fronts within the Slope waters north of the Gulf Stream and along the Reykjanes Ridge are examples of underlying complexities in the mean field that have yet to be adequately explored and understood. Repeat sampling of weakly stratified waters can reveal strong fluxes that might otherwise might go undetected due to a lack of the baroclinity that we often depend upon to define currents. Given careful calibration and intercomparison with quantitative measures, backscatter information can provide powerful qualitative information on biological activity. Besides the well-known diel migration of mesopelagic fishes and zooplankton, one can also identify striking pattern changes across fronts and in eddy structures. Today remote sensing of currents and biomass to depths greater than 1 km is readily available technology. This remote sensing tool offers tremendous opportunities for ocean exploration on the one hand, and how the oceans may be responding to and partnering in global change on the other.

Rossby, H. T.; Flagg, C. N.; Ortner, P. B.

2010-12-01

339

The Next Generation Deep Space Network: Meeting the Needs of Future Human and Robotic Space Exploration Missions  

NASA Astrophysics Data System (ADS)

NASA's Deep Space Network (DSN) is evolving to meet the communication and navigation needs of increasingly complex, data-intensive exploration and space science missions, both human and robotic. Solar system exploration missions, for instance, are focusing more on long-duration orbital remote sensing at increasing spatial, spectral, and temporal resolutions. Such missions are also conducting more elaborate in situ investigations - with short-lived probes being superceded by multiple, long-lived, mobile robotic explorers. Meanwhile, solar and astrophysical missions are moving from low-Earth-orbit, single-spacecraft observatories to multi-spacecraft observatories operating in more distant Earth-trailing and Lagrange point orbits. In the coming decades, human missions will play a key role in exploring the Moon and, eventually, Mars. Analysis of NASA's roadmap missions suggests that, over the next 25 years, these various changes will drive downlink and uplink rates up by a factor of at least 1,000 - even from the more distant regions of our solar system. At the same time, the trend toward multi-spacecraft missions will likely cause a doubling in the number of such links back to Earth. To meet these challenges, the DSN is transforming its network of large antennas to a hybrid network of large arrays of small antennas, optical communications terminals, and, at destinations undergoing intensive exploration, relay satellites. It is also developing more capable spacecraft communications components and systems and is exploring more accurate navigation techniques. All of these capabilities are being designed to play together in a seamless, cost-effective reliable manner, providing 21st century missions with a 21st century DSN. This work was performed in part at the Jet Propulsion Laboratory, California Institute of Technology, under contract to NASA

Preston, R. A.; Abraham, D. S.; Deutsch, L. J.; Geldzahler, B.

2004-12-01

340

Human Exploration using Real-Time Robotic Operations (HERRO): A space exploration strategy for the 21st century  

NASA Astrophysics Data System (ADS)

This paper presents an exploration strategy for human missions beyond Low Earth Orbit (LEO) and the Moon that combines the best features of human and robotic spaceflight. This “Human Exploration using Real-time Robotic Operations” (HERRO) strategy refrains from placing humans on the surfaces of the Moon and Mars in the near-term. Rather, it focuses on sending piloted spacecraft and crews into orbit around Mars and other exploration targets of interest, and conducting astronaut exploration of the surfaces using telerobots and remotely-controlled systems. By eliminating the significant communications delay or “latency” with Earth due to the speed of light limit, teleoperation provides scientists real-time control of rovers and other sophisticated instruments. This in effect gives them a “virtual presence” on planetary surfaces, and thus expands the scientific return at these destinations. HERRO mitigates several of the major issues that have hindered the progress of human spaceflight beyond Low Earth Orbit (LEO) by: (1) broadening the range of destinations for near-term human missions; (2) reducing cost and risk through less complexity and fewer man-rated elements; (3) offering benefits of human-equivalent in-situ cognition, decision-making and field-work on planetary bodies; (4) providing a simpler approach to returning samples from Mars and planetary surfaces; and (5) facilitating opportunities for international collaboration through contribution of diverse robotic systems. HERRO provides a firm justification for human spaceflight—one that expands the near-term capabilities of scientific exploration while providing the space transportation infrastructure needed for eventual human landings in the future.

Schmidt, George R.; Landis, Geoffrey A.; Oleson, Steven R.

2012-11-01

341

Direct-current-like Phase Space Manipulation Using Chirped Alternating Current Fields  

SciTech Connect

Waves in plasmas can accelerate particles that are resonant with the wave. A dc electric field also accelerates particles, but without a resonance discrimination, which makes the acceleration mechanism profoundly different. Whereas wave-particle acceleration mechanisms have been widely discussed in the literature, this work discusses the direct analogy between wave acceleration and dc field acceleration in a particular parameter regime explored in previous works. Apart from the academic interest of this correspondence, there may be practical advantages in using waves to mimic dc electric fields, for example, in driving plasma current with high efficiency.

P.F. Schmit and N.J. Fisch

2010-02-01

342

Generation of Relativistic Electron Bunches with Arbitrary Current Distribution via Transverse-to-Longitudinal Phase Space Exchange  

SciTech Connect

We propose a general method for tailoring the current distribution of relativistic electron bunches. The technique relies on a recently proposed method to exchange the longitudinal phase space emittance with one of the transverse emittances. The method consists of transversely shaping the bunch and then converting its transverse profile into a current profile via a transverse-to-longitudinal phase-space-exchange beamline. We show that it is possible to tailor the current profile to follow, in principle, any desired distributions. We demonstrate, via computer simulations, the application of the method to generate trains of microbunches with tunable spacing and linearly-ramped current profiles. We also briefly explore potential applications of the technique.

Piot, P.; /NICADD, DeKalb /Fermilab; Sun, Y.-E; /Fermilab; Power, J.G.; /Argonne; Rihaoui, M.; /NICADD, DeKalb

2010-07-01

343

MECHANICAL COUNTER PRESSURE SPACE SUITS: ADVANTAGES, LIMITATIONS AND CONCEPTS FOR MARTIAN EXPLORATION  

Microsoft Academic Search

Gas-pressurised space suits have been highly effect ive as a life support system, but are a severe hindrance to astronaut function and capabili ty. They are rigid, heavy, bulky, costly, leaky, and require high maintenance due to the comp lexity of constant volume joints and associated bearings and restraint layers. For futu re planetary exploration, revolutionary suit designs must be

James M. A. Waldie

344

Low-Power High-Speed Smart Sensor Design for Space Exploration Missions.  

National Technical Information Service (NTIS)

A low-power high-speed smart sensor system based on a large format active pixel sensor (APS) integrated with a programmable neural processor for space exploration missions is presented. The concept of building an advanced smart sensing system is demonstra...

W. C. Fang

1997-01-01

345

Application-specific clustered VLIW datapaths: early exploration on a parameterized design space  

Microsoft Academic Search

Specialized clustered very large instruction word (VLIW) processors combined with effective compilation tech- niques enable aggressive exploitation of the high instruction-level parallelism inherent in many embedded media applications, while unlocking a variety of possible performance\\/cost tradeoffs. In this work, the authors propose a methodology to support early design space exploration of clustered VLIW datapaths, in the context of a specific

Viktor S. Lapinskii; Margarida F. Jacome; Gustavo A. de Veciana

2002-01-01

346

Retargetable profiling for rapid, early system-level design space exploration  

Microsoft Academic Search

Fast and accurate estimation is critical for exploration of any design space in general. As we move to higher levels of abstraction, estimation of complete system designs at each level of abstraction is needed. Estimation should provide a variety of useful metrics relevant to design tasks in different domains and at each stage in the design process.In this paper, we

Lukai Cai; Andreas Gerstlauer; Daniel Gajski

2004-01-01

347

A genetic algorithm for the design space exploration of datapaths during high-level synthesis  

Microsoft Academic Search

High-level synthesis is comprised of interdependent tasks such as scheduling, allocation, and module selection. For today's very large-scale integration (VLSI) designs, the cost of solving the combined scheduling, allocation, and module selection problem by exhaustive search is prohibitive. However, to meet design objectives, an extensive design space exploration is often critical to obtaining superior designs. We present a framework for

Vyas Krishnan; Srinivas Katkoori

2006-01-01

348

An Iterative Algorithm for Hardware-Software Partitioning, Hardware Design Space Exploration and Scheduling  

Microsoft Academic Search

The paper proposes a novel heuristic technique for integrated hardware-software partitioning, hardware design space exploration and scheduling. The technique maps an application specified as a task graph on a heterogeneous architecture with an objective to minimize the latency of the task graph subject to the area constraint on the hardware coprocessor. The technique uses an iterative approach where the partitioner

Karam S. Chatha; Ranga Vemuri

2000-01-01

349

Reliability Programs and the Problem of Attaining High Probabilities of Mission Success in Space Exploration  

Microsoft Academic Search

The major obstacles to attaining high probabilities of mission success in future space exploration are described to be as follows: dependence on large numbers of propulsive stages in a given vehicle development of relatively many more long-lived components and subsystems than has been possible to achieve to date heed to improve the development process so that a reletively much ower

Nicholas E. Golovin

1964-01-01

350

Exploring the design space of cache memories, bus width, and burst transfer memory systems  

Microsoft Academic Search

Caches, data path, and burst transfer memory are the major hardware techniques used to reduce the latency between the processor and the main memory. We explore the design space among the hit ratio (hence a cache size, or an improved cache structure), data path width, and the transfer memory design through a performance tradeoff methodology. For the tradeoffs among these

1998-01-01

351

Between unsafe spaces and the comfort zone? Exploring the impact of learning environments on 'doing' learning  

Microsoft Academic Search

This paper explores how learning can be understood as a liminal space or transitional journey from one way of knowing to another? and where 'doing' learning is as much about being inculcated into the un­noticed rules and conventions of education itself as it is about developing understanding of the content of a subject discipline. By starting from Meyer and Land's

Jos Boys

352

Nuclear safety policy working group recommendations on nuclear propulsion safety for the space exploration initiative  

Microsoft Academic Search

An interagency Nuclear Safety Working Group (NSPWG) was chartered to recommend nuclear safety policy, requirements, and guidelines for the Space Exploration Initiative (SEI) nuclear propulsion program. These recommendations, which are contained in this report, should facilitate the implementation of mission planning and conceptual design studies. The NSPWG has recommended a top-level policy to provide the guiding principles for the development

Albert C. Marshall; James H. Lee; William H. McCulloch; J. Charles Sawyer Jr.; Robert A. Bari; Hatice S. Cullingford; Alva C. Hardy; George F. Niederauer; Kerry Remp; John W. Rice

1993-01-01

353

Defining and exploring public space: perspectives of young people from Regent Park, Toronto  

Microsoft Academic Search

Inner city public housing figures prominently on the urban regeneration agenda. Regent Park, Toronto, Canada's largest and oldest public housing development, is in the midst of a 15-year, billion dollar revitalisation plan involving extensive physical and social changes. This paper explores how Regent Park's young people define and value public space and compares this with the revitalisation plan. Findings reveal

Danielle Leahy Laughlin; Laura C. Johnson

2011-01-01

354

Hybrid Analytical-Statistical Modeling for Efficiently Exploring Architecture and Workload Design Spaces  

Microsoft Academic Search

Abstract: Microprocessor design time and effort are getting impractical due to the huge number of simulations that need to be done to evaluate various processor configurations for various workloads. An early design stage methodology could be useful to efficiently cull huge design spaces to identify regions of interest to be further explored using more accurate simulations. In this paper, we

Lieven Eeckhout; Koenraad De Bosschere

2001-01-01

355

Implications of Outside-the-Box Technologies on Future Space Exploration and Colonization  

Microsoft Academic Search

In general, planning for future manned space exploration either to the moon, Mars, or an asteroid has depended on a somewhat linear extrapolation of our present technologies. Two major prohibitive cost issues regarding such planning are payload lift and in-flight energy generation. The costs of these in both engineering and actual flight costs, coupled with the planning necessary to carry

Theodore C. Loder

356

Implications of Outside-the-Box Technologies on Future Space Exploration and Colonization  

Microsoft Academic Search

In general, planning for future manned space exploration either to the moon, Mars, or an asteroid has depended on a somewhat linear extrapolation of our present technologies. Two major prohibitive cost issues regarding such planning are payload lift and in-flight energy generation. The costs of these in both engineering and actual flight costs, coupled with the planning necessary to carry

Theodore C. Loder

2003-01-01

357

Pareto front feature selection: using genetic programming to explore feature space  

Microsoft Academic Search

In this paper we use genetic programming (GP) for feature selection in binary classification tasks. Mathematical expressions built by GP transform the feature space in a way that the relevance of subsets of features can be measured using a simple relevance function. We make some modifications to the standard GP to make it explore large subsets of features when necessary.

Kourosh Neshatian; Mengjie Zhang

2009-01-01

358

Gigantic Follies. Human Exploration and the Space Age in Long-term Historical Perspective.  

National Technical Information Service (NTIS)

This chapter attempts to place the whole endeavor of the Space Age into a global historical context. The motivation for exploration that human history has chronicled, according to the author throughout the history of our species, has had less to do with a...

J. R. McNeill

2008-01-01

359

Rapid Design Space Exploration of Application Specific Heterogeneous Pipelined Multiprocessor Systems  

Microsoft Academic Search

This paper describes a rapid design methodology to create a pipeline of processors to execute streaming applications. The methodology seeks a system with the smallest area while its runtime is within a specified runtime constraint. Initially, a heuristic is used to rapidly explore a large number of processor configurations to find the near Pareto front of the design space, and

Haris Javaid; Aleksandar Ignjatovic; Sri Parameswaran

2010-01-01

360

A quadratic regulator-based heuristic for rapidly exploring state space  

Microsoft Academic Search

Kinodynamic planning algorithms like Rapidly-Exploring Randomized Trees (RRTs) hold the promise of finding feasible trajectories for rich dynamical systems with complex, nonconvex constraints. In practice, these algorithms perform very well on configuration space planning, but struggle to grow efficiently in systems with dynamics or differential constraints. This is due in part to the fact that the conventional distance metric, Euclidean

Elena Leah Glassman; Russ Tedrake

2010-01-01

361

Exploring c-Met kinase flexibility by sampling and clustering its conformational space.  

PubMed

It is now widely recognized that the flexibility of both partners has to be considered in molecular docking studies. However, the question how to handle the best the huge computational complexity of exploring the protein binding site landscape is still a matter of debate. Here we investigate the flexibility of c-Met kinase as a test case for comparing several simulation methods. The c-Met kinase catalytic site is an interesting target for anticancer drug design. In particular, it harbors an unusual plasticity compared with other kinases ATP binding sites. Exploiting this feature may eventually lead to the discovery of new anticancer agents with exquisite specificity. We present in this article an extensive investigation of c-Met kinase conformational space using large-scale computational simulations in order to extend the knowledge already gathered from available X-ray structures. In the process, we compare the relevance of different strategies for modeling and injecting receptor flexibility information into early stage in silico structure-based drug discovery pipeline. The results presented here are currently being exploited in on-going virtual screening investigations on c-Met. PMID:22275094

Asses, Yasmine; Venkatraman, Vishwesh; Leroux, Vincent; Ritchie, David W; Maigret, Bernard

2012-01-24

362

Identifying Organic Molecules in Space - The AstroBiology Explorer (ABE) MIDEX Mission Concept  

NASA Astrophysics Data System (ADS)

Infrared spectroscopy in the 2.5-16 micron range is a principle means by which organic compounds can be detected and identified in space via their vibrational transitions. Ground-based, airborne, and spaceborne IR spectral studies have already demonstrated that a significant fraction of the carbon in the interstellar medium (ISM) resides in the form of complex organic molecular species. Unfortunately, neither the distribution of these materials nor their genetic and evolutionary relationships with each other or their environments are well understood. The Astrobiology Explorer (ABE) is a MIDEX mission concept currently under study at NASA's Ames Research Center in collaboration with Ball Aerospace and Technologies Corporation. ABE will conduct IR spectroscopic observations to address outstanding important problems in astrobiology, astrochemistry, and astrophysics. The core observational program would make fundamental scientific progress in understanding (1) the evolution of ices and organic matter in dense molecular clouds and young forming stellar systems, (2) the chemical evolution of organic molecules in the ISM as they transition from AGB outflows to planetary nebulae to the general diffuse ISM to HII regions and dense clouds, (3) the distribution of organics in the diffuse ISM, (4) the nature of organics in the Solar System (in comets, asteroids, satellites), and (5) the nature and distribution of organics in local galaxies. The technical considerations of achieving these science objectives in a MIDEX-sized mission will be presented.

Sandford, S. A.; Allamandola, L. J.; Bregman, J.; Ennico, K.; Greene, T.; Hudgins, D.; Strecker, D.

2001-05-01

363

Design and Performance Analysis of Downlink in Space Communications System for Lunar Exploration  

NASA Astrophysics Data System (ADS)

Korean government made clear that it would make efforts to carry out full-fledged research into space exploration with the aim of developing a Lunar Orbiter (LO) from 2017 to 2020 in the detailed implement guidance of the space development project established in 2007 (Lee 2009). To make the plan realized, basic researches into a space communication link are essential (Kim et al. 2009). However, local researches in Korea were focused on the near-earth satellite communication links and the researches on the deep space communications were hardly founded. This paper designs and analyzes the downlink between a LO and an Earth Station (ES) in space communications system for lunar exploration, and suggests requirements for the communication link design with conforming to international recommendations. In general, among the losses in the calculation of a space communication link budget between the LO and the ES, the largest one is the free space loss comes from the distance between the earth and the moon. Furthermore, an accurate link model should be made up in order to analyze the performance in a more accurate way, with all the other elements influencing on signal quality. In this paper, we design the model of a space communications system considering almost all elements to affect the downlink performance of the space communications system between the LO and the ES, based on detailed requirements by CCSDS (the Consultative Committee for Space Data Systems, 2007), and verify the results with reference to the foreign operation cases of NASA (National Aeronautics and Space Administration) DSN (Deep Space Network) (Slobin 2006, Sniffin 2002, 2008). According to the CCSDS, we assume that the communication links have the line of sight path between the LO and the ES for S, X, Ku, and Ka bands, and an uncoded OQPSK signal is considered for a telemetry transmission. Also, a required target BER (Bit Error Rate) in the downlink space communications systems is assumed to be 10^5. We calculate the Eb=N0 (Bit Energy to Noise Power Density Ratio) with the designed model for a downlink space communications system, and compare it with the required Eb=N0 to satisfy the target BER. Then, we analyze the link performance between the LO and the ES depending on the data rates, the diameters of antennas, and the transmit powers in S, X, Ku, and Ka bands. The remainder of this paper is organized as follows: section 2 introduces a system model, section 3 analyzes the performance of the downlink space communications system, and the final section gives conclusions.

Lee, Wooju; Cho, Kyongkuk; Yoon, Dongweon

2010-03-01

364

Past Realities Versus Hypothetical Futures: Bridging Accurate Perceptions and Individual Expectations Gaps in Relation to Future Space Exploration at Entertainment Attractions  

NASA Astrophysics Data System (ADS)

Past Realities Versus Hypothetical Futures: Bridging Accurate Perceptions and Individual Expectation Gaps in Relation to It has been more than forty years since the dawn of the space age and the notion of human space flight has settled comfortably into the human psyche. Yet there is disconnect between the cinematic representations of space exploration and long-term program plans of national space agencies. For entertainment attractions, too often these cinematic representations cloud public perceptions of the art of the possible in space exploration. The forecasts of personal hover mobiles, ubiquitous robots, and luxury cruises to the moon that were to be available to society at the end of the last century have turned out to be grossly exaggerated. This results in continued frustration and subsequent ambivalence of the public towards space. Eventually, these misperceptions have a direct relationship to the level of support shown by legislative bodies towards public outlays for space exploration. The value proposition to society of space has changed, from one of transformational change (Apollo) to transactional apathy (the current Space Shuttle). The past realities of the space program and the potential futures enabled by the current generation of space scientists and engineers will not be equivalent. Yet there is an opportunity to showcase the best of the upcoming future without defrauding the public's imagination. At the start of this century, new visions of the future are being prepared by various entertainment entities (e.g. for movies, them park attractions). This examination consists of a review of previous paradigms of translating space visions to the public. Given the background of the authors in conceptual space engineering, recommendations are made as to more scientifically credible attractions while maintaining the entertainment proposition. Different scenarios are presented as to potential futures and impact of these on entertainment attractions. Criteria are given as to the characteristics of exhibits that can be robust enough for both the near term and will not fall into the trap of being outdated by actual events.

Charania, A.; Bradford, J.; Shkirenko, A.

2002-01-01

365

A phenomenological exploration of reflections on lived space by child sexual abusers.  

PubMed

Child sexual abusers may be better understood by phenomenological exploration of reflections on childhood lived space. Child sexual abusers often suffer from child sexual abuse, physical abuse, and neglect in their childhood lived space. These experiences may be considered a limitation or deformation of the child's lived space, resulting in a distorted self view that contributes to adult behavior. Child sexual abuse is not a new phenomenon; it is a problem that has existed throughout history but has rarely enjoyed the publicity and concern of recent times. Child sexual abusers' reflections on their lived space during childhood were explored by interviewing eight incarcerated child sexual abusers in a US correctional center. Van Manen's descriptive-interpretive theoretical process was used to guide abusers' existential reflections on their childhood lived space. van Manen's phenomenological method is dynamic and was used to organize and analyze data into essential categorical themes, one of which is "failure to root." While the viewpoint is retrospective, participants in this study provided unique perspectives on childhood reflections on lived space. These experiences, as reported by the participants, could be used to assist child victims to cope and to guide nursing practice, education, and future research related to Healthy People 2010's Goal 15 (Healthy People 2010, n.d.). PMID:21142595

Garrett, Linda H

2010-12-01

366

An integrated mission approach to the space exploration initiative will ensure success  

SciTech Connect

The direction of the American space program, as defined by President Bush and the National Commission on Space, is to expand human presence into the solar system. Landing an American on Mars by the 50th anniversary of the Apollo 11 lunar landing is the goal. This challenge has produced a level of excitement among young Americans not seen for nearly three decades. The exploration and settlement of the space frontier will occupy the creative thoughts and energies of generations of Americans well into the next century. The return of Americans to the moon and beyond must be viewed as a national effort with strong public support if it is to become a reality. Key to making this an actuality is the mission approach selected. Developing a permanent presence in space requires a continual stepping outward from Earth in a logical progressive manner. If we seriously plan to go and to stay, then not only must we plan what we are to do and how we are to do it, we must address the logistic support infrastructure that will allow us to stay there once we arrive. A fully integrated approach to mission planning is needed if the Space Exploration Initiative (SEI) is to be successful. Only in this way can a permanent human presence in space be sustained. An integrated infrastructure approach would reduce the number of new systems and technologies requiring development. The resultant horizontal commonality of systems and hardware would reduce the direct economic impact of SEI while an early return on investment through technology spin-offs would be an economic benefit by greatly enhancing our international technical competitiveness. If the exploration, development, and colonization of space is to be affordable and acceptable, careful consideration must be given to such things as return on investment'' and commercial product potential'' of the technologies developed. 7 refs., 3 figs.

Coomes, E.P.; Dagle, J.E.; Bamberger, J.A.; Noffsinger, K.E.

1990-10-01

367

An integrated mission approach to the space exploration initiative will ensure success  

SciTech Connect

The direction of the American space program, as defined by President Bush and the National Commission on Space, is to expand human presence into the solar system. Landing an American on Mars by the 50th anniversary of the Apollo 11 lunar landing is the goal. This challenge has produced a level of excitement among young Americans not seen for nearly three decades. The exploration and settlement of the space frontier will occupy the creative thoughts and energies of generations of Americans well into the next century. The return of Americans to the moon and beyond must be viewed as a national effort with strong public support if it is to become a reality. Key to making this an actuality is the mission approach selected. Developing a permanent presence in space requires a continual stepping outward from Earch in a logical progressive manner. If we seriously plan to go and to stay, then not only must we plan what we are to do and how we are to do it, we must address the logistic support infrastructure that will allow us to stay there once we arrive. A fully integrated approach to mission planning is needed if the Space exploration Initiative (SEI) is to be successful. Only in this way can a permanent human presence in space be sustained. An integrated infrastructure approach would reduce the number of new systems and technologies requiring development. The resultant horizontal commonality of systems and hardware would reduce the direct economic impact of SEI while an early return on investment through technology spin-offs would be an economic benefit by greatly enhancing our international technical competitiveness. If the exploration, development, and colonization of space is to be affordable and acceptable, careful consideration must be given to such things as return on investment'' and commercial product potential'' of the technologies developed.

Coomes, E.P.; Dagle, J.E.; Bamberger, J.A.; Noffsinger, K.E. (Pacific Northwest Laboratory, P.O. Box 999, M/S K5-21, Richland, Washington 99352 (US))

1991-01-05

368

Mars Wars: The Rise and Fall of the Space Exploration Initiative  

NASA Astrophysics Data System (ADS)

The rise of Space Exploration Initiative (SEI) and its eventual demise represents one of the landmark episodes in the history of the American space program ranking with the creation of NASA, the decision to go to the Moon, the post-Apollo planning process, and the space station decision. The story of this failed initiative is one shaped by key protagonists and critical battles. It is a tale of organizational, cultural, and personal confrontation. Organizational skirmishes involved the Space Council versus NASA, the White House versus congressional appropriators, and the Johnson Space Center versus the rest of the space agency all seeking control of the national space policy process. Cultural struggles pitted the increasingly conservative engineering ethos of NASA against the faster, better, cheaper philosophy of a Space Council looking for innovative solutions to technical problems. Personality clashes matched Vice President Dan Quayle and Space Council Executive Secretary Mark Albrecht against NASA Administrator Dick Truly and Johnson Space Center Director Aaron Cohen. In the final analysis, the demise of SEI was a classic example of a defective decision-making process one that lacked adequate high-level policy guidance, failed to address critical fiscal constraints, developed inadequate programmatic alternatives, and garnered no congressional support. Some space policy experts have argued that SEI was doomed to fail, due primarily to the immense budgetary pressures facing the nation during the early 1990's. This book will argue, however, that the failure of the initiative was not predetermined; instead, it was the result of a deeply flawed policy process that failed to develop (or even consider) policy options that may have been politically acceptable given the existing political environment.

Hogan, Thor

2007-08-01

369

Space physiology IV: mathematical modeling of the cardiovascular system in space exploration.  

PubMed

Mathematical modeling represents an important tool for analyzing cardiovascular function during spaceflight. This review describes how modeling of the cardiovascular system can contribute to space life science research and illustrates this process via modeling efforts to study postflight orthostatic intolerance (POI), a key issue for spaceflight. Examining this application also provides a context for considering broader applications of modeling techniques to the challenges of bioastronautics. POI, which affects a large fraction of astronauts in stand tests upon return to Earth, presents as dizziness, fainting and other symptoms, which can diminish crew performance and cause safety hazards. POI on the Moon or Mars could be more critical. In the field of bioastronautics, POI has been the dominant application of cardiovascular modeling for more than a decade, and a number of mechanisms for POI have been investigated. Modeling approaches include computational models with a range of incorporated factors and hemodynamic sophistication, and also physical models tested in parabolic and orbital flight. Mathematical methods such as parameter sensitivity analysis can help identify key system mechanisms. In the case of POI, this could lead to more effective countermeasures. Validation is a persistent issue in modeling efforts, and key considerations and needs for experimental data to synergistically improve understanding of cardiovascular responses are outlined. Future directions in cardiovascular modeling include subject-specific assessment of system status, as well as research on integrated physiological responses, leading, for instance, to assessment of subject-specific susceptibility to POI or effects of cardiovascular alterations on muscular, vision and cognitive function. PMID:23539439

Keith Sharp, M; Batzel, Jerry Joseph; Montani, Jean-Pierre

2013-03-29

370

Exploring the Phase Space of the Quantum {delta}-Kicked Accelerator  

SciTech Connect

We experimentally explore the underlying pseudoclassical phase space structure of the quantum {delta}-kicked accelerator. This was achieved by exposing a Bose-Einstein condensate to the spatially corrugated potential created by pulses of an off-resonant standing light wave. For the first time quantum accelerator modes were realized in such a system. By utilizing the narrow momentum distribution of the condensate we were able to observe the discrete momentum state structure of a quantum accelerator mode and also to directly measure the size of the structures in the phase space.

Behinaein, G.; Ramareddy, V.; Ahmadi, P.; Summy, G. S. [Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078-3072 (United States)

2006-12-15

371

Exploring the phase space of the quantum delta-kicked accelerator.  

PubMed

We experimentally explore the underlying pseudoclassical phase space structure of the quantum delta-kicked accelerator. This was achieved by exposing a Bose-Einstein condensate to the spatially corrugated potential created by pulses of an off-resonant standing light wave. For the first time quantum accelerator modes were realized in such a system. By utilizing the narrow momentum distribution of the condensate we were able to observe the discrete momentum state structure of a quantum accelerator mode and also to directly measure the size of the structures in the phase space. PMID:17280289

Behinaein, G; Ramareddy, V; Ahmadi, P; Summy, G S

2006-12-13

372

Automation and robotics for the Space Exploration Initiative: Results from Project Outreach  

NASA Astrophysics Data System (ADS)

A total of 52 submissions were received in the Automation and Robotics (A&R) area during Project Outreach. About half of the submissions (24) contained concepts that were judged to have high utility for the Space Exploration Initiative (SEI) and were analyzed further by the robotics panel. These 24 submissions are analyzed here. Three types of robots were proposed in the high scoring submissions: structured task robots (STRs), teleoperated robots (TORs), and surface exploration robots. Several advanced TOR control interface technologies were proposed in the submissions. Many A&R concepts or potential standards were presented or alluded to by the submitters, but few specific technologies or systems were suggested.

Gonzales, D.; Criswell, D.; Heer, E.

373

International Space Environment Service: Current Activities and Future Plans  

NASA Astrophysics Data System (ADS)

The International Space Environment Service ISES is a permanent service of the Federations of Astronomical and Geophysical Data Analysis Services FAGS with the mission to encourage and facilitate near-real-time international monitoring and prediction of the space environment This is done through the work of Regional Warning Centres RWC around the world who collaborate in the exploitation of a wide range of space-based and ground-based data Rapid exchange of information about the space environment is facilitated through the use of standard URSIgram codes RWCs also collaborate in sharing expertise in particular areas of specialty ISES also prepares the International Geophysical Calendar IGC each year giving a list of World Days during which scientists are encouraged to carry out their experiments and the monthly Spacewarn Bulletins which summarize the status of satellites in earth orbit and in the interplanetary medium ISES has its origins in the former URSI Central Committee of USRIgrams which initiated rapid international data interchange services in 1928 The modern system of regional warning centres was set up during the International Geophysical Year and now exist in every populated continent except Africa and South America ISES as part of its IGY 50 activities is working to develop RWCs in those continents ISES is also involved in developing new multi-national space weather services for example for trans-polar flights New space-based data on space weather activity will require extensive collaboration if it is to be

Boteler, D. H.; H. Lundstedt, H.; Kunches, J.; Coffey, H.; Hilgers, A.; Patterson, G.; van der Linden, R.; Lam, H.-L.; Wang, H.; Buresova, D.; et al.

374

A methodology for the validated design space exploration of fuel cell powered unmanned aerial vehicles  

NASA Astrophysics Data System (ADS)

Unmanned Aerial Vehicles (UAVs) are the most dynamic growth sector of the aerospace industry today. The need to provide persistent intelligence, surveillance, and reconnaissance for military operations is driving the planned acquisition of over 5,000 UAVs over the next five years. The most pressing need is for quiet, small UAVs with endurance beyond what is capable with advanced batteries or small internal combustion propulsion systems. Fuel cell systems demonstrate high efficiency, high specific energy, low noise, low temperature operation, modularity, and rapid refuelability making them a promising enabler of the small, quiet, and persistent UAVs that military planners are seeking. Despite the perceived benefits, the actual near-term performance of fuel cell powered UAVs is unknown. Until the auto industry began spending billions of dollars in research, fuel cell systems were too heavy for useful flight applications. However, the last decade has seen rapid development with fuel cell gravimetric and volumetric power density nearly doubling every 2--3 years. As a result, a few design studies and demonstrator aircraft have appeared, but overall the design methodology and vehicles are still in their infancy. The design of fuel cell aircraft poses many challenges. Fuel cells differ fundamentally from combustion based propulsion in how they generate power and interact with other aircraft subsystems. As a result, traditional multidisciplinary analysis (MDA) codes are inappropriate. Building new MDAs is difficult since fuel cells are rapidly changing in design, and various competitive architectures exist for balance of plant, hydrogen storage, and all electric aircraft subsystems. In addition, fuel cell design and performance data is closely protected which makes validation difficult and uncertainty significant. Finally, low specific power and high volumes compared to traditional combustion based propulsion result in more highly constrained design spaces that are problematic for design space exploration. To begin addressing the current gaps in fuel cell aircraft development, a methodology has been developed to explore and characterize the near-term performance of fuel cell powered UAVs. The first step of the methodology is the development of a valid MDA. This is accomplished by using propagated uncertainty estimates to guide the decomposition of a MDA into key contributing analyses (CAs) that can be individually refined and validated to increase the overall accuracy of the MDA. To assist in MDA development, a flexible framework for simultaneously solving the CAs is specified. This enables the MDA to be easily adapted to changes in technology and the changes in data that occur throughout a design process. Various CAs that model a polymer electrolyte membrane fuel cell (PEMFC) UAV are developed, validated, and shown to be in agreement with hardware-in-the-loop simulations of a fully developed fuel cell propulsion system. After creating a valid MDA, the final step of the methodology is the synthesis of the MDA with an uncertainty propagation analysis, an optimization routine, and a chance constrained problem formulation. This synthesis allows an efficient calculation of the probabilistic constraint boundaries and Pareto frontiers that will govern the design space and influence design decisions relating to optimization and uncertainty mitigation. A key element of the methodology is uncertainty propagation. The methodology uses Systems Sensitivity Analysis (SSA) to estimate the uncertainty of key performance metrics due to uncertainties in design variables and uncertainties in the accuracy of the CAs. A summary of SSA is provided and key rules for properly decomposing a MDA for use with SSA are provided. Verification of SSA uncertainty estimates via Monte Carlo simulations is provided for both an example problem as well as a detailed MDA of a fuel cell UAV. Implementation of the methodology was performed on a small fuel cell UAV designed to carry a 2.2 kg payload with 24 hours of endurance. Uncertainty distributions for both design

Moffitt, Blake Almy

375

Media spaces: past visions, current realities, future promise  

Microsoft Academic Search

Established researchers and practitioners active in the development and deployment of media spaces review what seemed to be promised twenty years ago, what has actually been achieved, and what we might anticipate over the next twenty years.

Ronald Baecker; Steve R. Harrison; William Buxton; Steven E. Poltrock; Elizabeth F. Churchill

2008-01-01

376

Extension of PWM space vector technique for multilevel current-controlled voltage source inverters  

Microsoft Academic Search

The space vector technique is widely used to shape the inverter output currents. In order to improve the inverter performance, especially in high-voltage applications, multilevel inverters structures are utilized. The conventional space vector technique cannot be applied to control the multilevel inverter output currents. In this paper, a generalized method for controlling the output currents of this type of inverter

J. Mahdavi; A. Agah; A. M. Ranjbar; H. A. Toliyat

1999-01-01

377

Review and Synthesis of Considerations in Architecting Heterogeneous Teams of Humans and Robots for Optimal Space Exploration  

Microsoft Academic Search

Human-robot systems will play a critical role in space exploration, should NASA embark on missions to the Moon and Mars. A unified framework to optimally leverage the capabilities of humans and robots in space exploration will be an invaluable tool for mission planning. Although there is a growing body of literature on human-robot interactions, there is not yet a framework

Julie Ann Shah; Joseph H. Saleh; Jeffrey A. Hoffman

2007-01-01

378

Design space exploration algorithm for heterogeneous multi-processor embedded system design  

Microsoft Academic Search

Single-chip multi-processor embedded system becomesnowadays a feasible and very interesting option. What isneeded however is an environment that supports the designerin transforming an algorithmic specification into a suitableparallel implementation. In this paper we present anddemonstrate an important component of such an environment - an efficient design space exploration algorithm. The algorithm can be used to semi-automatically find the bestparallelization of

Ireneusz Karkowski; Henk Corporaal

1998-01-01

379

A Sensitivity-Based Design Space Exploration Methodology for Embedded Systems  

Microsoft Academic Search

In this paper, we propose a system-level design methodology for the efficient exploration of the architectural parameters of the memory sub-systems, from the energy-delay joint perspective. The aim is to find the best configuration of the memory hierarchy without performing the exhaustive analysis of the parameters space. The target system architecture includes the processor, separated instruction and data caches, the

WILLIAM FORNACIARI; DONATELLA SCIUTO; CRISTINA SILVANO; VITTORIO ZACCARIA

2002-01-01

380

Using estimates from behavioral synthesis tools in compiler-directed design space exploration  

Microsoft Academic Search

This paper considers the role of performance and area estimates from behavioral synthesis in design space exploration. We have developed a compilation system that automatically maps high-level algorithms written in C to application-specific designs for Field Programmable Gate Arrays (FPGAs), through a collaboration between parallelizing compiler technology and high-level synthesis tools. Using several code transformations, the compiler optimizes a design

Byoungro So; Pedro C. Diniz; Mary W. Hall

2003-01-01

381

Design-Space Exploration of Power-Aware On\\/Off Interconnection Networks  

Microsoft Academic Search

With power a major limiting factor in the design of scalable interconnected systems, power-aware networks will become inherent components of single-chip and multi-chip systems. As commu- nication links consume significant power regardless of utilization, we propose and investigate power-aware networks whose links are turned on and off in response to bursts and dips in traffic. We explore the design space

Vassos Soteriou; Li-shiuan Peh

2004-01-01

382

Distributed design-space exploration for high-level synthesis systems  

Microsoft Academic Search

A parallel algorithm for design-space exploration and trade-o flanalysis is presented, Coarse-grained parallelism is introduced by generating multiple module bags and perjorming scheduling andperjormance analysis of the data j?owgraph joreach module bagin parallel. This algorithm is impiementedon a multiple pr-ocessor machine as part of a distributed high-leuel synthesis s~stem. Experimental results show reduction in search time, improvement in design quality,

Rajiv Dutta; Jayanta Roy; Ranga Vemuri

1992-01-01

383

An MCM\\/IC timing-driven placement algorithm featuring explicit design space exploration  

Microsoft Academic Search

A genetic algorithm for building-block placement of MCMs and ICs is presented which simultaneously minimizes layout area and an Elmore-based estimate of the maximum path delay while trying to meet a target aspect ratio. Explicit design space exploration is performed by using a vector-valued, S-dimensional cost function and searching for a set of distinct solutions representing the best tradeoffs of

Henrik Esbensen; E. S. Euh

1996-01-01

384

Leisure, business and fantasy worlds: exploring donor-funded ‘youth spaces’ in southern Kyrgyzstan  

Microsoft Academic Search

This article explores the participation of university students in non-governmental organizations (NGOs) and other forms of association in the city of Osh, Kyrgyzstan. While the literature tends to criticize donor interventions in the post-Soviet space, an analysis of donor-funded youth projects calls for a more differentiated evaluation. It is argued that youth-oriented associations appeal to the students of Osh because

Stefan B. Kirmse

2009-01-01

385

Closed cycle MHD power generation system driven by nuclear reactor for space exploration  

Microsoft Academic Search

For deep space explorations, we have to develop high-efficiency, high-reliability and high-performance electric power generation system. In this paper, a closed cycle magnetohydrodynamic (CCMHD) power generation system directly driven by a nuclear fission reactor (NFR) was proposed and investigated. Output electric power level is multi-MWe. Particularly, influence of the number of compressor stages, the regenerator efficiency and the radiator temperature

N. Harada; C. Buttapeng

2004-01-01

386

Rapid exploration of configuration space with diffusion-map-directed molecular dynamics.  

PubMed

The gap between the time scale of interesting behavior in macromolecular systems and that which our computational resources can afford often limits molecular dynamics (MD) from understanding experimental results and predicting what is inaccessible in experiments. In this paper, we introduce a new sampling scheme, named diffusion-map-directed MD (DM-d-MD), to rapidly explore molecular configuration space. The method uses a diffusion map to guide MD on the fly. DM-d-MD can be combined with other methods to reconstruct the equilibrium free energy, and here, we used umbrella sampling as an example. We present results from two systems: alanine dipeptide and alanine-12. In both systems, we gain tremendous speedup with respect to standard MD both in exploring the configuration space and reconstructing the equilibrium distribution. In particular, we obtain 3 orders of magnitude of speedup over standard MD in the exploration of the configurational space of alanine-12 at 300 K with DM-d-MD. The method is reaction coordinate free and minimally dependent on a priori knowledge of the system. We expect wide applications of DM-d-MD to other macromolecular systems in which equilibrium sampling is not affordable by standard MD. PMID:23865517

Zheng, Wenwei; Rohrdanz, Mary A; Clementi, Cecilia

2013-08-07

387

Chemodiversity and molecular plasticity: recognition processes as explored by property spaces.  

PubMed

In the last few years, a need to account for molecular flexibility in drug-design methodologies has emerged, even if the dynamic behavior of molecular properties is seldom made explicit. For a flexible molecule, it is indeed possible to compute different values for a given conformation-dependent property and the ensemble of such values defines a property space that can be used to describe its molecular variability; a most representative case is the lipophilicity space. In this review, a number of applications of lipophilicity space and other property spaces are presented, showing that this concept can be fruitfully exploited: to investigate the constraints exerted by media of different levels of structural organization, to examine processes of molecular recognition and binding at an atomic level, to derive informative descriptors to be included in quantitative structure--activity relationships and to analyze protein simulations extracting the relevant information. Much molecular information is neglected in the descriptors used by medicinal chemists, while the concept of property space can fill this gap by accounting for the often-disregarded dynamic behavior of both small ligands and biomacromolecules. Property space also introduces some innovative concepts such as molecular sensitivity and plasticity, which appear best suited to explore the ability of a molecule to adapt itself to the environment variously modulating its property and conformational profiles. Globally, such concepts can enhance our understanding of biological phenomena providing fruitful descriptors in drug-design and pharmaceutical sciences. PMID:21707401

Vistoli, Giulio; Pedretti, Alessandro; Testa, Bernard

2011-06-01

388

The application of nuclear power and propulsion for space exploration missions  

SciTech Connect

An approach to integrating nuclear technology into space exploration missions is advanced that is based on conditioning nuclear technology to be broadly applicable across the existing mission set. Two similar baselines are presented for small nuclear thermal rocket (NTR) engines for exploration missions. Small NTR engines are also examined in terms of their use in manned Mars missions, and the Integrated Power and Propulsion Stage (IPPS) is illustrated for providing electric power and direct thermal thrust for a variety of missions. An IPPS is proposed for use in the Titan IV launch, earth orbital missions, and for applications such as instrument delivery and exploration missions. The paper concludes the review of NTR engine technology possibilities by suggesting that the keys to integrating NTR engines are versatility and synergism. 8 refs.

Zubrin, R.M.; Sulmeisters, T.K. (Martin Marietta Astronautics Group, Denver, CO (United States))

1992-07-01

389

The application of nuclear power and propulsion for space exploration missions  

NASA Astrophysics Data System (ADS)

An approach to integrating nuclear technology into space exploration missions is advanced that is based on conditioning nuclear technology to be broadly applicable across the existing mission set. Two similar baselines are presented for small nuclear thermal rocket (NTR) engines for exploration missions. Small NTR engines are also examined in terms of their use in manned Mars missions, and the Integrated Power and Propulsion Stage (IPPS) is illustrated for providing electric power and direct thermal thrust for a variety of missions. An IPPS is proposed for use in the Titan IV launch, earth orbital missions, and for applications such as instrument delivery and exploration missions. The paper concludes the review of NTR engine technology possibilities by suggesting that the keys to integrating NTR engines are versatility and synergism.

Zubrin, Robert M.; Sulmeisters, Tal K.

1992-07-01

390

"Amazing Space": Creating Educational Resources from Current Scientific Research Results from the Hubble Space Telescope.  

ERIC Educational Resources Information Center

|Introduces the Amazing Space program which is designed to enhance student mathematics, science, and technology skills using recent data and results from the National Aeronautics and Space Administration's (NASA) Hubble Space Telescope mission. Explains the process of designing multi-media resources in a five-week summer workshop that partners…

Christian, C. A.; Eisenhamer, B.; Eisenhamer, Jonathan; Teays, Terry

2001-01-01

391

Space Nuclear Power and Propulsion - a basic Tool for the manned Exploration of the Solar System  

SciTech Connect

Humanity has started to explore space more than 40 years ago. Numerous spacecraft have left the Earth in this endeavour, but while unmanned spacecraft were already sent out on missions, where they would eventually reach the outer limits of the Solar System, manned exploration has always been confined to the tiny bubble of the Earth's gravitational well, stretching out at maximum to our closest celestial companion - the Moon - during the era of the Apollo programme in the late 60's and early 70's. When mankind made its giant leap, the exploration of our cosmic neighbour was seen as the initial step for the manned exploration of the whole Solar System. Consequently ambitious research and development programmes were undertaken at that time to enable what seemed to be the next logical steps: the establishment of a permanent settled base on the Moon and the first manned mission to Mars in the 80's. Nuclear space power and propulsion played an important role in these entire future scenarios, hence ambitious development programmes were undertaken to make these technologies available. Unfortunately the 70's-paradigm shift in space policies did not only bring an end to the Apollo programme, but it also brought a complete halt to all of these technology programmes and confined the human presence in space to a tiny bubble including nothing more than the Earth's sphere and a mere shell of a few hundred kilometres of altitude, too small to even include the Moon. Today, after more than three decades, manned exploration of the Solar System has become an issue again and so are missions to Moon and Mars. However, studies and analyses show that all of these future plans are hampered by today's available propulsion systems and by the problematic of solar power generation at distances at and beyond of Mars, a problem, however, that can readily be solved by the utilisation of space nuclear reactors and propulsion systems. This paper intends to provide an overview on the various fission- and fusion-based Nuclear Power and Propulsion system concepts and tries to compare these systems' different working principles and technical implementations with each other. The overview and comparison will be complemented by a closer look at ongoing activities related to research and development in this area and by an outlook on what kind of systems might be employed to carry the first astronauts to Mars and beyond. (autho0008.

Frischauf, Norbert; Hamilton, Booz Allen [ESA/ESTEC, Keplerlaan 1, P.O. Box 29, NL-2200 AG Noordwijk (Netherlands)

2004-07-01

392

Study explores space weather risk to natural gas pipeline in Finland  

Microsoft Academic Search

Data being collected on the Finnish natural gas pipeline are providing a basis for estimating the space weather risk for the pipeline and for designing possible countermeasures. Finland's high latitude location makes such systems prone to problems caused by geomagnetically induced currents (GICs),but so far no harm has been detected. The statistical GIC risk in the Finnish high-voltage power system

Risto Pirjola; Antti Pulkkinen; Ari Viljanen; Heikki Nevanlinna; Kari Pajunpää

1999-01-01

393

U. S.-U. S. S. R. Space Exploration and Technology, John F. Kennedy, and the Press.  

ERIC Educational Resources Information Center

Debates and policies in the late 1950s and early 1960s regarding the United States-Soviet space race are described in this paper, and an analysis is presented of press coverage of President John F. Kennedy's public statements regarding space technology and exploration. The first sections of the paper present a selected space chronology from 1957…

Babcock, William A.; Ostman, Ronald E.

394

The AstroBiology Explorer (ABE) MIDEX Mission Concept: Identifying Organic Molecules in Space  

Microsoft Academic Search

The Astrobiology Explorer (ABE) is a MIDEX mission concept, currently under Concept Phase A study at NASA's Ames Research Center in collaboration with Ball Aerospace &Technologies, Corp., and managed by NASA's Jet Propulsion Laboratory. ABE will conduct infrared spectroscopic observations to address important problems in astrobiology, astrochemistry, and astrophysics. The core observational program would make fundamental scientific progress in understanding

Kimberly A. Ennico; Scott Sandford; Louis Allamandola; Jesse D. Bregman; Martin Cohen; Dale Cruikshank; Thomas P. Greene; Douglas Hudgins; Sun Kwok; Steven D. Lord; Suzanne Madden; Craig R. McCreight; Thomas L. Roellig; Donald W. Strecker; A. G. G. M. Tielens; Michael W. Werner

2003-01-01

395

The New World and the New Frontier: Studying the Age of Exploration and the Space Age with Elementary Students.  

ERIC Educational Resources Information Center

Discusses a social studies classroom unit for use with elementary students. Focuses on comparing the age of exploration and space age exploration. Provides background information on both explorations and compares the similarities and differences between the two. Includes suggestions and questions for using this interdisciplinary approach. (CMK)

Fritzer, Penelope; Ploger, Don

2001-01-01

396

Current Developments in Basic Space Science in Nigeria  

Microsoft Academic Search

Astronomy is important to developing African countries. In this paper, a brief review of the situation of astronomical research in Africa before 1991 is given. During that period only South Africa and Egypt were carrying out observational research in astronomy. In other African countries astronomy research was in its infancy, except the University of Nigeria Space Research Centre (UNNSRC) in

P. N. Okeke

2004-01-01

397

Current Developments in Basic Space Science in Nigeria  

NASA Astrophysics Data System (ADS)

Astronomy is important to developing African countries. In this paper, a brief review of the situation of astronomical research in Africa before 1991 is given. During that period only South Africa and Egypt were carrying out observational research in astronomy. In other African countries astronomy research was in its infancy, except the University of Nigeria Space Research Centre (UNNSRC) in theoretical areas. A summary of the important recommendations for Africa at the United Nations/ European Space Agency (UN/ESA) series of workshops on basic space science were itemized to help identify those which have now been accomplished. Additionally, UNNSRC has now embarked on further observational programmes through the establishment of strong collaborative ventures with two observatories in South Africa, the Hartesbeesthoek Radio Astronomical Observatory (Hart RAO) and the South African Astronomical Observatory (SAAO). UNNSRC has also made permanent arrangements with HartRAO, SAAO, and the Jodrell Bank for collaborations in data analysis. A new interest in astronomy appears to have awakened in Nigeria with three more universities joining this area of basic space science. It is recommended that the time has come for all African countries to contribute towards a common facility such as the Southern African Large Telescope (SALT). The efforts of UN/ESA which resulted in tremendous achievements are commended.

Okeke, P. N.

398

The Value of Humans in the Biological Exploration OF?SPACE  

NASA Astrophysics Data System (ADS)

Regardless of the discovery of life on Mars, or of “no apparent life” on Mars, the questions that follow will provide a rich future for biological exploration. Extraordinary pattern recognition skills, decadal assimilation of data and experience, and rapid sample acquisition are just three of the characteristics that make humans the best means we have to explore the biological potential of Mars and other planetary surfaces. I make the case that instead of seeing robots as in conflict, or even in support, of human exploration activity, from the point of view of scientific data gathering and analysis, we should view humans as the most powerful robots we have, thus removing the separation that dogs discussions on the exploration of space. The narrow environmental requirements of humans, although imposing constraints on the life support systems required, is more than compensated for by their capabilities in biological exploration. I support this view with an example of the “Christmas present effect,” a simple demonstration of human data and pattern recognition capabilities.

Cockell, C. S.

2004-06-01

399

Exploration  

USGS Publications Warehouse

This summary of international nonfuel mineral exploration activities for 1998 draws on available data from literature, industry and US Geological Survey (USGS) specialists. Data on exploration budgets by region and commodity are reported, significant mineral discoveries and exploration target areas are identified and government programs affecting the mineral exploration industry are discussed. Inferences and observations on mineral industry direction are drawn from these data and discussions.

Wilburn, D. R.; Porter, K. E.

1999-01-01

400

International Space Station as a base camp for exploration beyond low Earth orbit  

NASA Astrophysics Data System (ADS)

The idea for using the International Space Station (ISS) as a platform for exploration has matured in the past few years and the concept continues to gain momentum. ISS provides a robust infrastructure which can be used to test systems and capabilities needed for missions to the Moon, Mars, asteroids and other potential destinations. International cooperation is a critical enabler and ISS has already demonstrated successful management of a large multi-national technical endeavor. Systems and resources needed for expeditions can be aggregated and thoroughly tested at ISS before departure thus providing wide operational flexibility and the best assurance of mission success. A small part of ISS called an Exploration Platform (ISS-EP) can be placed in cislunar space providing immediate benefits and flexibility for future exploration missions. We will show how ISS and the ISS-EP can be used to reduce risk and improve the operational flexibility for missions beyond low Earth orbit. Life support systems and other technologies developed for ISS can be evolved and adapted to the ISS-EP and other exploration spacecrafts. New technology, such as electric propulsion and advanced life support systems can be tested and proven at ISS as part of an incremental development program. Commercial companies who are introducing transportation and other services will benefit with opportunities to contribute to the mission since ISS will serve as a focal point for the commercialization of low earth orbit services. Finally, we will show how the use of ISS provides immediate benefits to the scientific community because its capabilities are available today and certain critical aspects of exploration missions can be simulated.

Raftery, Michael; Hoffman, Jeffrey

2013-04-01

401

Current Developments in Basic Space Science in Nigeria  

Microsoft Academic Search

Astronomy is important to developing African countries. In this paper, a brief review of the situation of astronomical research\\u000a in Africa before 1991 is given. During that period only South Africa and Egypt were carrying out observational research in\\u000a astronomy. In other African countries astronomy research was in its infancy, except the University of Nigeria Space Research\\u000a Centre (UNNSRC) in

P. N. Okeke

402

An exploration of the potential of WWW current awareness services for oncology nurses  

Microsoft Academic Search

Purpose – The potential of current awareness services (CAS) for oncology nurses is considered with special reference to the spectrum of WWW CAS that are available, their benefits and problems, and how these can be linked to the dynamic health environments in which oncology nurses may find themselves. The intention with the article is to show the need for exploring

Ina Fourie; Retha Claasen-veldsman

2007-01-01

403

Survey Exploring Views of Scientists on Current Trends in Chemistry Education  

ERIC Educational Resources Information Center

A survey exploring the views of scientists, chemists and chemical engineers, on current trends in Chemistry Education was conducted in Greece. Their opinions were investigated using a questionnaire focusing on curricula (the content and process of chemistry teaching and learning), as well as on the respondents' general educational beliefs and…

Vamvakeros, Xenofon; Pavlatou, Evangelia A.; Spyrellis, Nicolas

2010-01-01

404

Exploration of Current Trends of the Arts Policy in America: Within the Economic and Educational Aspects  

Microsoft Academic Search

The purpose of this article is to explore and analyze the current trends of the arts policy in America within the aspects of economics and education. There are five parts in this article of the arts policy in America, including background, ideology and effects, contents, analysis and a conclusion. Study and observation have led to several conclusions. The trends of

Maxine Huang

405

Face recognition by exploring information jointly in space, scale and orientation.  

PubMed

Information jointly contained in image space, scale and orientation domains can provide rich important clues not seen in either individual of these domains. The position, spatial frequency and orientation selectivity properties are believed to have an important role in visual perception. This paper proposes a novel face representation and recognition approach by exploring information jointly in image space, scale and orientation domains. Specifically, the face image is first decomposed into different scale and orientation responses by convolving multiscale and multiorientation Gabor filters. Second, local binary pattern analysis is used to describe the neighboring relationship not only in image space, but also in different scale and orientation responses. This way, information from different domains is explored to give a good face representation for recognition. Discriminant classification is then performed based upon weighted histogram intersection or conditional mutual information with linear discriminant analysis techniques. Extensive experimental results on FERET, AR, and FRGC ver 2.0 databases show the significant advantages of the proposed method over the existing ones. PMID:20643604

Lei, Zhen; Liao, Shengcai; Pietikäinen, Matti; Li, Stan Z

2010-07-19

406

Novel space vector based current controllers for PWM-inverters  

Microsoft Academic Search

Two novel, simple control strategies for current-controlled pulse-width modulated (PWM) transistor inverters are presented. Both methods are based on the three-level hysteresis comparators which select appropriate inverter output voltage vectors via a switching electrically programmable read-only memory (EPROM) table. The first controller works with current components represented in a stationary coordinate system (AC components) and the second with components represented

M. P. Kazmierkowski; M. A. Dzieniakowski; W. Sulkowski

1991-01-01

407

New Insights about Cross-Contamination Procedures for Analogue Missions in Space Exploration  

NASA Astrophysics Data System (ADS)

Environments such as the surface of other planets like Mars are subject to contamination processes by human exploration. Therefore, this is a crucial issue for planetary protection which needs to be addressed before investigating possible extraterrestrial life forms. Within AustroMars, the module track & trace assessed the dimension of back- and forward contamination which was verifiable in both directions. Sterile filters which were exposed to the environment during repeated EVAs showed persistent contaminations with bacteria. On-site contamination within the habitat was checked by exposed agar plates which were all positive with cultivable strains. The second module LiMa ("Life on Mars") simulates sterile procedures to collect samples with subsequent cultivation efforts under harsh conditions. These modules have been accomplished under high fidelity conditions and are the first analogue experiments conducted within the background of space exploration.

Sattler, B.; Selch, F.; Klammer, S.; Groemer, G.; Sipiera, P.

2007-10-01

408

Heavy-lift launch vehicle options for future space exploration initiatives  

NASA Astrophysics Data System (ADS)

A review of present heavy-lift launch vehicles (HLLV) capable of placing heavy payloads in earth orbit is presented and the basis for an emerging consensus that an HLLV will be required in the near future is discussed. Some of the factors for the policies governing the roles and requirements for these vehicles in the future, such as cost, technology development, and lead time to first use are addressed. Potential Space Station Freedom application is discussed as well as application to the proposed initiatives for human exploration of Mars and the moon.

Branscome, Darrell R.; Harris, Ronald J.

1990-10-01

409

Students for the Exploration and Development of Space: The Messier Catalog  

NSDL National Science Digital Library

Messier Objects are covered with images, links, and descriptions on this Students for the Exploration and Development of Space (SEDS) website. Detailed information is given on Messier and how he discovered these objects, which include nebulae, star clusters, and galaxies, all cataloged by number. For each Messier Object known, the user can access an image, proper name, location, additional links, and description with history of the object. There is also a Messier object of the week, and a clickable icon sheet to view objects. The information is available in English, German, Italian, and French.

Frommert, Harmut; Kronberg, Christine

410

Thermoelectric Alloys and Devices for Radioisotope Space Power Systems: State of the Art and Current Developments  

SciTech Connect

Lead telluride and silicon germanium type alloys have served over the past several decades as the preferred thermoelectric conversion materials for U. S. radioisotope thermoelectric generator (RTG) power systems for planetary deep space exploration missions. The Pioneer missions to Jupiter and Jupiter/Saturn and the Viking Mars Lander missions employed TAGS-2N (lead and germanium telluride derivatives) power conversion devices. Since 1976, silicon germanium (SiGe) alloys, incorporated into the unicouple device, have evolved as the thermoelectric materials of choice for U. S. RTG powered space missions. These include the U. S. Air Force Lincoln Experimental Satellites 8 & 9 for communications, in 1976, followed in 1977 by the National Aeronautics and Space Administration Voyager 1 and 2 planetary missions. In 1989, advanced SiGe RTGs were used to power the Galileo exploration of Jupiter and, in 1990, will be used to power the Ulysses investigation of the Sun. In addition, SiGe technology has been chosen to provide RTG power for the 1995 Comet Rendezvous and Asteroid Flyby mission and the 1996 Cassini Saturn orbiter mission. Summaries of the flight performance data for these systems are presented.; Current U. S. Department of Energy thermoelectric development activities include (1) the development of conversion devices based on hi-density, close packed couple arrays and (2) the development of improved performance silicon germanium type thermoelectric materials. The silicon germanium type "multicouple", being developed in conjunction with the Modular RTG program, is discussed in a companion paper. A lead telluride type close-packed module, discussed herein, offers the promise of withstanding high velocity impacts and, thus, is a candidate for a Mars Penetrator application.; Recent projects sponsored by the U. S. Department of Energy, including the Improved Thermoelectric Materials and Modular Radioisotope Thermoelectric Generator programs, have shown that improvements in silicon germanium thermoelectric energy conversion capabilities of at least 50 percent can be achieved by tailoring the characteristics of the silicon germanium alloy materials and devices. This paper compares the properties and characteristics of the SiGe alloys now being developed with those used in the operational space power system.

Barnett, W.; Dick, P.; Beaudry, B.; Gorsuch, P.; Skrabek, E.

1989-01-01

411

Measurement realities of current collection in dynamic space plasma environments  

NASA Astrophysics Data System (ADS)

Theories which describe currents collected by conducting and non-conducting bodies immersed in plasmas have many of their concepts based upon the fundamentals of sheath-potential distributions and charged-particle behavior in superimposed electric and magnetic fields. Those current-collecting bodies (or electrodes) may be Langmuir probes, electric field detectors, aperture plates on ion mass spectrometers and retarding potential analyzers, or spacecraft and their rigid and tethered appendages. Often the models are incomplete in representing the conditions under which the current-voltage characteristics of the electrode and its system are to be measured. In such cases, the experimenter must carefully take into account magnetic field effects and particle anisotropies, perturbations caused by the current collection process itself and contamination on electrode surfaces, the complexities of non-Maxwellian plasma distributions, and the temporal variability of the local plasma density, temperature, composition and fields. This set of variables is by no means all-inclusive, but it represents a collection of circumstances guaranteed to accompany experiments involving energetic particle beams, plasma discharges, chemical releases, wave injection and various events of controlled and uncontrolled spacecraft charging. Here, an attempt is made to synopsize these diagnostic challenges and frame them within a perspective that focuses on the physics under investigation and the requirements on the parameters to be measured. Examples include laboratory and spaceborne applications, with specific interest in dynamic and unstable plasma environments.

Szuszczewicz, Edward P.

1990-12-01

412

NASA's First in-Space Optical Gyroscope: A Technology Experiment on the X ray Timing Explorer Spacecraft.  

National Technical Information Service (NTIS)

A technology experiment on the X-ray Timing Explorer spacecraft to determine the feasibility of Interferometric Fiber Optic Gyroscopes for space flight navigation is described. The experiment consists of placing a medium grade fiber optic gyroscope in par...

G. Unger D. M. Kaufman M. Krainak G. Sanders B. Taylor

1993-01-01

413

Enabling technologies for space exploration systems: The STEPS project results and perspectives  

NASA Astrophysics Data System (ADS)

The project STEPS (Sistemi e Tecnologie per l'EsPlorazione Spaziale) is a joint development of technologies and systems for Space Exploration supported by Regione Piemonte, the European Regional Development Fund (E.R.D.F.) 2007-2013, Thales Alenia Space Italia (TAS-I), SMEs, Universities and public Research Centres belonging to the network "Comitato Distretto Aerospaziale del Piemonte" the Piedmont Aerospace District (PAD) in Italy. The project first part terminated in May 2012 with a final demonstration event that summarizes the technological results of research activities carried-out during a period the three years and half. The project developed virtual and hardware demonstrators for a range of technologies for the descent, soft landing and surface mobility of robotic and manned equipment for Moon and Mars exploration. The two key hardware demonstrators—a Mars Lander and a Lunar Rover—fit in a context of international cooperation for the exploration of Moon and Mars, as envisaged by Space Agencies worldwide. The STEPS project included also the development and utilization of a system of laboratories equipped for technology validation, teleoperations, concurrent design environments, and virtual reality simulation of the Exploration Systems in typical Moon and Mars environments. This paper presents the reached results in several technology domains like: vision-based GNC for the last portion of Mars Entry, Descent and Landing sequence, Hazard avoidance and complete spacecraft autonomy; Autonomous Rover Navigation, based on the determination of the terrain morphology by a stereo camera; Mobility and Mechanisms providing an Integrated Ground Mobility System, Rendezvous and Docking equipment, and protection from Environment effects; innovative Structures such as Inflatable, Smart and Multifunction Structures, an Active Shock Absorber for safe landing, balance restoring and walking; Composite materials Modelling and Monitoring; Human-machine interface features of a predictive Command and Control System; Energy Management systems based on Regenerative Fuel Cells; aerothermodynamic solutions for Atmospheric Re-entry of Commercial Transportation Systems; novel Design and Development Tools, such as a Rover S/W simulator and prototypes of the DEM viewer and of a S/W Rock Creator/visualizator. The paper also provides perspectives on the proposed STEPS 2 project that will likely continue the development of a subset of the above technologies in view of their possible in-flight validation within next five years.

Messidoro, Piero; Perino, Maria Antonietta; Boggiatto, Dario

2013-05-01

414

Survey Exploring Views of Scientists on Current Trends in Chemistry Education  

Microsoft Academic Search

A survey exploring the views of scientists, chemists and chemical engineers, on current trends in Chemistry Education was\\u000a conducted in Greece. Their opinions were investigated using a questionnaire focusing on curricula (the content and process\\u000a of chemistry teaching and learning), as well as on the respondents’ general educational beliefs and their underlying epistemological\\u000a views. The aim of this work was

Xenofon Vamvakeros; Evangelia A. Pavlatou; Nicolas Spyrellis

2010-01-01

415

High-power constant current technique for the excitation source of electromagnetic exploration on land  

Microsoft Academic Search

In the field of geophysical exploration, one of effective methods to detect buried metal ores is multiple-frequency fusion electromagnetic excitation and its imaging. This technique needs to set a high-power artificial EM source in subsurface of the target area. To facilitate supply of such a large power, a constant current of high-voltage is necessary. However, some factors such as heterogeneities

Fusheng Shi; Ming Deng; Meng Wang; Yingying Liu

2009-01-01

416

Meander: visually exploring the structural variome using space-filling curves  

PubMed Central

The introduction of next generation sequencing methods in genome studies has made it possible to shift research from a gene-centric approach to a genome wide view. Although methods and tools to detect single nucleotide polymorphisms are becoming more mature, methods to identify and visualize structural variation (SV) are still in their infancy. Most genome browsers can only compare a given sequence to a reference genome; therefore, direct comparison of multiple individuals still remains a challenge. Therefore, the implementation of efficient approaches to explore and visualize SVs and directly compare two or more individuals is desirable. In this article, we present a visualization approach that uses space-filling Hilbert curves to explore SVs based on both read-depth and pair-end information. An interactive open-source Java application, called Meander, implements the proposed methodology, and its functionality is demonstrated using two cases. With Meander, users can explore variations at different levels of resolution and simultaneously compare up to four different individuals against a common reference. The application was developed using Java version 1.6 and Processing.org and can be run on any platform. It can be found at http://homes.esat.kuleuven.be/~bioiuser/meander.

Pavlopoulos, Georgios A.; Kumar, Parveen; Sifrim, Alejandro; Sakai, Ryo; Lin, Meng Lay; Voet, Thierry; Moreau, Yves; Aerts, Jan

2013-01-01

417

Meander: visually exploring the structural variome using space-filling curves.  

PubMed

The introduction of next generation sequencing methods in genome studies has made it possible to shift research from a gene-centric approach to a genome wide view. Although methods and tools to detect single nucleotide polymorphisms are becoming more mature, methods to identify and visualize structural variation (SV) are still in their infancy. Most genome browsers can only compare a given sequence to a reference genome; therefore, direct comparison of multiple individuals still remains a challenge. Therefore, the implementation of efficient approaches to explore and visualize SVs and directly compare two or more individuals is desirable. In this article, we present a visualization approach that uses space-filling Hilbert curves to explore SVs based on both read-depth and pair-end information. An interactive open-source Java application, called Meander, implements the proposed methodology, and its functionality is demonstrated using two cases. With Meander, users can explore variations at different levels of resolution and simultaneously compare up to four different individuals against a common reference. The application was developed using Java version 1.6 and Processing.org and can be run on any platform. It can be found at http://homes.esat.kuleuven.be/~bioiuser/meander. PMID:23605045

Pavlopoulos, Georgios A; Kumar, Parveen; Sifrim, Alejandro; Sakai, Ryo; Lin, Meng Lay; Voet, Thierry; Moreau, Yves; Aerts, Jan

2013-04-19

418

Current collection from the space plasma through defects in solar array insulation  

Microsoft Academic Search

Operating high-voltage solar arrays in the space environment can result in anomalously large currents being collected through small insulation defects. Tests simulating the electron collection have shown that there are two major collection modes. The first involves current enhancement by means of a surface phenomenon involving secondary electron emission from the surrounding insulator. In the second mode, the current collection

R. S. Robinson; R. P. Stillwell; H. R. Kaufman

1985-01-01

419

Space experiment BTN-NEUTRON on INTERNATIONAL SPACE STATION - CURRENT STATUS and future stages  

NASA Astrophysics Data System (ADS)

Space experiment BTN (Board Telescope of Neutrons) was suggested in 1997 for the Russian segment of International Space Station. The first stage of this experiment was started in February 2007 with instrumentation BTN-M1, which contain two separate units: 1) the electronics unit for commanding and data handling, which is installed inside the Station; 2) the detector unit, which is installed at the outer surface of Russian Service Module "Zvezda". The total mass of this instrument without cables is about 15 kg and total power consumption is about 18 Watts. Detector unit of BTN-M1 has the set of four neutron detectors: three proportional counters of epithermal neutrons with 3He covered by cadmium shields and polyethylene moderators with different thickness and stylbene scintillator for fast neutrons at the energy range 0.4 Mev - 10 Mev. There are three sources of neutrons in the near-Earth space. Permanent flux of neutrons is produced due to interaction of energetic particles of galactic and solar cosmic rays with the upper atmosphere of the Earth ("natural neutrons") and with the body of the spacecraft ("technogenic neutrons"). The third transient sources of neutrons are active regions of the Sun, which may sporadically emit energetic neutrons during strong flares. Some of these particles have sufficiently high energy to neutrons cover the distance to the Earth before decay Data from BTN-M1 after 2 years of space operations is sufficient for preliminary estimation of neutron component of radiation environment in the near-Earth space. BTN-M1 detector unit is equal to the Russian instrument HEND, which also operates now onboard NASA's Mars Odyssey orbiter since May 2001. Simultaneous measurements of neutron radiation on orbits around Mars and Earth give the unique opportunity to compare neutron radiation environment around two planets. The technogenic component of neutron background may be estimated by analysis of data for different stages of flight. After evaluation of local background, the natural components of neutron radiation environment around two planets are deconvolved from the data of two instruments. Using the data from HEND/MO and BTN/ISS for 2007 - 2008 years time interval, the neutron contribution to the total radiation doze is estimated in conditions of solar minimum both for near-Earth and near-Mars space. In 2009 - 2010, when the rising phase of the next 24th solar cycle will be in progress, the data of measurements of HEND/MO and BTN/ISS will allow to model space environment for more complex conditions, when decreasing flux of galactic cosmic rays will be compensated by episodes of powerful solar particles events. Presently instrumentation BTN-M2 for the 2nd stage of space experiment BTN-Neutron is designed, which will allow to study the neutron fluxes in different places inside of Station. This data will allow to compare neutrons outside and inside Station at different conditions of orbital flight. Detector unit of BTN-M2 will be surrounded by different shielding materials, which are known as good neutron moderators and absorbers. Measurements with shielded and open detectors will provide the experimental data for designing future spacecraft for long space flights in the interplanetary space.

Tretyakov, V. I.; Kozyrev, A. S.; Laygushin, V. I.; Litvak, M. L.; Malakhov, A. V.; Mitrofanov, I. G.; Mokrousov, M. I.; Pronin, M. A.; Vostrukhin, A. A.; Sanin, A. B.

2009-04-01

420

Modular, Adaptive, Reconfigurable Systems: Technology for Sustainable, Reliable, Effective, and Affordable Space Exploration  

NASA Astrophysics Data System (ADS)

In order to execute the Vision for Space Exploration, we must find ways to reduce cost, system complexity, design, build, and test times, and at the same time increase flexibility to satisfy multiple functions. Modular, Adaptive, Reconfigurable System (MARS) technologies promise to set the stage for the delivery of system elements that form the building blocks of increasingly ambitious missions involving humans and robots. Today, space systems are largely specialized and built on a case-by-case basis. The notion of modularity however, is nothing new to NASA. The 1970's saw the development of the Multi-Mission Modular spacecraft (MMS). From 1980 to 1992 at least six satellites were built under this paradigm, and included such Goddard Space Flight Center missions as SSM, EUVE, UARS, and Landsat 4 and 5. Earlier versions consisted of standard subsystem ``module'' or ``box'' components that could be replaced within a structure based on predefined form factors. Although the primary motivation for MMS was faster/cheaper integration and test, standardization of interfaces, and ease of incorporating new subsystem technology, it lacked the technology maturity and programmatic ``upgrade infrastructure'' needed to satisfy varied mission requirements, and ultimately it lacked user buy-in. Consequently, it never evolved and was phased out. Such concepts as the Rapid Spacecraft Development Office (RSDO) with its regularly updated catalogue of pre-qualified busses became the preferred method for acquiring satellites. Notwithstanding, over the past 30 years since MMS inception, technology has advanced considerably and now modularity can be extended beyond the traditional MMS module or box to cover levels of integration, from the chip, card, box, subsystem, to the space system and to the system-of-systems. This paper will present the MARS architecture, cast within the historical context of MMS. Its application will be highlighted by comparing a state-of-the-art point design vs. a MARS-enabled lunar mission, as a representative robotic case design.

Esper, Jaime

2005-02-01

421

The Case of the Great Space Exploration: An Educator Guide with Activities in Mathematics, Science, and Technology. The NASA SCI Files. EG-2004-09-12-LARC  

ERIC Educational Resources Information Center

|In this companion to the "NASA SCI Files" episode "The Case of the Great Space Exploration," the tree house detectives learn about NASA's new vision for exploring space. In four segments aimed at grades 3-5, students learn about a variety of aspects of space exploration. Each segment of the guide includes an overview, a set of objectives,…

Ricles, Shannon; Jaramillo, Becky; Fargo, Michelle

2004-01-01

422

NASA's Office of Aeronautics and Exploration Technology space power flight projects  

NASA Astrophysics Data System (ADS)

NASA created a program called In-STEP (in-space technology experiments program) to give the aerospace community an opportunity to validate advanced technologies in space. In-STEP has funded feasibility studies for the following experiments in the power technology arena: a microsphere insulation investigation, a utilized regenerative fuel cell experiment, an inflatable solar collector experiment, a moving belt radiator experiment, and a liquid drop radiator experiment. The following experiments are currently in the experiment definition phase: an integrated two-phase thermal experiment, an electrolysis performance experiment, and a sodium sulfur battery experiment. Three In-STEP experiments are entering the hardware fabrication phase: thermal energy storage technology, solar array module plasma interaction, and heat pipe performance experiments. Each of these experiments is described, with an emphasis on the benefits of technology validation.

Chmielewski, Art B.; Pyle, Jon S.

423

Long-term modulation of galactic cosmic radiation and its model for space exploration  

NASA Astrophysics Data System (ADS)

As the human exploration of space has received new attention in the United States, studies find that exposure to space radiation could adversely impact the mission design. Galactic Cosmic Radiation (GCR), with its very wide range of charges and energies, is particularly important for a mission to Mars, because it imposes a stiff mass penalty for spacecraft shielding. Dose equivalent versus shielding thickness calculations, show a rapid initial drop on exposure with thickness, but an asymptotic behavior at a higher shielding thickness. Uncertainties in the radiobiology are largely unknown. For a fixed radiation risk, this leads to large uncertainties in shielding thickness for small uncertainties in estimated dose. In this paper we investigate the application of steady-state, spherically-symmetric diffusion-convection theory of solar modulation to individual measurements of differential energy spectra from 1954 to 1989 in order to estimate the diffusion coefficient, kappa(r,t), as a function of time. We have correlated the diffusion coefficient to the Climax neutron monitor rates and show that, if the diffusion coefficient can be separated into independent functions of space and time: kappa(r,t)=K(t) k0 beta Pk1 (r), where beta is the particle velocity and P the rigidity, then (i) The time dependent quantity 1/K(t), which is proportional to the deceleration potential, phi(r,t), is linearly related to the Climax neutron monitor counting rate. (ii) The coefficients obtained from hydrogen or helium intensity measurements are the same. (iii) There are different correlation functions for odd and even solar cycles. (iv) The correlation function for the Climax neutron monitor counting rate for given time, t, can be used to estimate mean deceleration parameter phi(t) to within +/- 15% with 90% confidence. We have shown that k(r,t) determined from hydrogen and/or helium data, can be used to fit the oxygen and iron differential energy spectra with a root mean square error of about +/- 10%, and essentially independent of the particle charge or energy. We have also examined the ion chamber and C-14 measurements which allow the analysis to be extended from the year 1906 to 1990. Using this model we have defined reference GCR spectra at solar minimum and solar maximum. These can be used for space exploration studies and provide a quantitative estimate of the error in dose due to changes in GCR intensities.

Badhwan, G. D.; O'Neill, P. M.

1994-10-01

424

Exploring near and far regions of space: Distance-specific visuospatial neglect after stroke.  

PubMed

Visuospatial neglect has been observed in the horizontal (left/right) and vertical (up/down) dimension and depends on the distance at which a task is presented (near/far). Previously, studies have mainly focused on investigating the overall severity of neglect in near and far space in a group of neglect patients instead of examining subgroups of neglect patients with different types of distance-specific neglect. We investigated the spatial specificity (near vs. far space), frequency, and severity of neglect in the horizontal and vertical dimensions in a large group of stroke patients. We used three tasks to assess neglect in near (30 cm) and far (120 cm) space: a shape cancellation, letter cancellation, and a line bisection task. Patients were divided into four groups based on their performance: a group without neglect (N-F-), a near only neglect (N+F-), a far only neglect (N-F+), and a near and far neglect group (N+F+). About 40% of our sample showed neglect. Depending on the task, N+F- was observed in 8 to 22% of the sample, whereas N-F+ varied between 8% and 11%, and N+F+ varied between 11% to 14% of the sample. The current findings indicate that horizontal and vertical biases in performance can be confined to one region of space and are task dependent. We recommend testing for far space neglect during neuropsychological assessments in clinical practice, because this cannot be diagnosed using standard paper-and-pencil tasks. PMID:23984973

Van der Stoep, Nathan; Visser-Meily, Johanna M A; Kappelle, L Jaap; de Kort, Paul L M; Huisman, Krista D; Eijsackers, Anja L H; Kouwenhoven, Mirjam; Van der Stigchel, Stefan; Nijboer, Tanja C W

2013-08-28

425

X-ray induced currents and space-charge buildup in MOS capacitors  

Microsoft Academic Search

The primary effect of ionizing radiation on the MOS structure is the buildup of positive space charge in the oxide layer. The purpose of this work was to study the results of the currents induced during X-irradiation in relation to the process of space charge buildup. The MOS structures used in the present study were made from thermally oxidized Si

J. W. Farmer

1974-01-01

426

Current collection by high voltage solar array from the space plasma  

SciTech Connect

This article presents a type of theoretical statistical model which is capable of conveniently calculating high voltage solar array (HVSA) current collections given rise to by space plasma. Through analysis of physical processes, it is believed that HVSA power consumption caused by space plasma should not be ignored with regard to HVSA design.

Shifen, G.; Liqin, S.; Li, S.; Baoning, T.

1996-08-20

427

A prospective health impact assessment of the international astronomy and space exploration centre  

PubMed Central

STUDY OBJECTIVES—Assess the potential health impacts of the proposed International Astronomy and Space Exploration Centre on the population of New Wallasey. Contribute to the piloting of health impact assessment methods.?DESIGN—Prospective health impact assessment involving brainstorming sessions and individual interviews with key informants and a literature review.?SETTING—New Wallasey Single Regeneration Budget 4 area.?PARTICIPANTS—Key stakeholders including local residents' groups selected through purposeful snowball sampling.?MAIN RESULTS—Recommendations are made that cover issues around: transport and traffic; civic design; security; public safety, employment and training.?CONCLUSIONS—Health impact assessment is a useful pragmatic tool for facilitating wide consultation. In particular engaging the local population in the early planning stages of a proposed development, and assisting in highlighting changes to maximise the positive health influences on affected communities.???Keywords: health impact assessment; health determinants

Winters, L

2001-01-01

428

The Stafford Commission synthesis group evaluation of power for the space exploration initiative  

NASA Astrophysics Data System (ADS)

Power for life support systems, experiments, operation of computers and communications equipment, preparation of sites, surface transportation, and extraction and processing resources from planetary surface is an essential element of the space exploration initiative. The philosophies for meeting power system requirements include: use of multiple units and power system types to ensure high reliability and safety; modular units that can be launched as a unit; minimization/elimination of off-earth assembly; emergency backup power for manned operational product improvement rather than developing the ultimate in the first unit; and adequate power options to satisfy anticipated power demand growth. The assessment approach used was to first examine the needs in terms of power level, duration, specific power, reliability, and need dates. Then, an assessment was performed of candidate technologies. A decision matrix was used to assess the candidate technologies relative to the needs. From this, candidate power systems were selected. Finally, particular systems are recommended for flight development.

Buden, David; Bartine, David; Harrison, Steve; Foremen, Joe; Biringer, Kent

429

Wall current probe: A non-invasive in situ plasma diagnostic for space and time resolved current density distribution measurement  

NASA Astrophysics Data System (ADS)

In the context of low temperature plasma research, we propose a wall current probe to determine the local charged particle fluxes flowing to the chamber walls. This non-intrusive planar probe consists of an array of electrode elements which can be individually biased and for which the current can be measured separately. We detail the probe properties and present the ability of the diagnostic to be used as a space and time resolved measurement of the ion and electron current density at the chamber walls. This diagnostic will be relevant to study the electron transport in magnetized low-pressure plasmas.

Baude, R.; Gaboriau, F.; Hagelaar, G. J. M.

2013-08-01

430

An assessment of prospects for international cooperation on the space exploration initiative  

NASA Astrophysics Data System (ADS)

This paper discusses: the unique characteristics of the Space Exploration Initiative (SEI) which will have to be taken into account if the Initiative is to become an international one; the technical capabilities offered by prospective international partners; the political and economic prospects for proceeding with the Initiative both in the United States and elsewhere; the advantages and disadvantages of various possible approaches to international cooperation on SEI; and some of the key issues which will have to be resolved if SEI is to become an international activity. International participation in SEI appears to be a very natural extension of prior space cooperation. There are common interests with a number of potential partners, and a substantial technical capability available outside the United States. However, world-wide political and economic prospects for actually proceeding with the Initiative in the near-term are uncertain. Consequently, SEI preparatory activities are likely to extend over a several-year period. Such an extended preparatory period should provide the time needed for coordinating studies, for identifying interests and potential contributions, and for resolving the numerous planning, budgeting, organizational and political issues which will have to be dealt with if such a complex undertaking is to be successfully internationalized.

Cline, Lynn F. H.; Rosendhal, Jeffrey D.

431

Planning ahead for asteroid and comet hazard mitigation, phase 1: parameter space exploration and scenario modeling  

SciTech Connect

The mitigation of impact hazards resulting from Earth-approaching asteroids and comets has received much attention in the popular press. However, many questions remain about the near-term and long-term, feasibility and appropriate application of all proposed methods. Recent and ongoing ground- and space-based observations of small solar-system body composition and dynamics have revolutionized our understanding of these bodies (e.g., Ryan (2000), Fujiwara et al. (2006), and Jedicke et al. (2006)). Ongoing increases in computing power and algorithm sophistication make it possible to calculate the response of these inhomogeneous objects to proposed mitigation techniques. Here we present the first phase of a comprehensive hazard mitigation planning effort undertaken by Southwest Research Institute and Los Alamos National Laboratory. We begin by reviewing the parameter space of the object's physical and chemical composition and trajectory. We then use the radiation hydrocode RAGE (Gittings et al. 2008), Monte Carlo N-Particle (MCNP) radiation transport (see Clement et al., this conference), and N-body dynamics codes to explore the effects these variations in object properties have on the coupling of energy into the object from a variety of mitigation techniques, including deflection and disruption by nuclear and conventional munitions, and a kinetic impactor.

Plesko, Catherine S [Los Alamos National Laboratory; Clement, R Ryan [Los Alamos National Laboratory; Weaver, Robert P [Los Alamos National Laboratory; Bradley, Paul A [Los Alamos National Laboratory; Huebner, Walter F [Los Alamos National Laboratory

2009-01-01

432

Enabling Opportunities for Large Space Telescopes in the Era of the Exploration Initiative  

NASA Astrophysics Data System (ADS)

We discuss enabling opportunities and implementation strategies for human and robotic servicing of a large space telescope operating at the Earth-Sun L2 location. The NASA SAFIR (Single Aperture Far Infrared) Vision Mission is used as a representative strawman case. Following earlier agency studies, we consider "gateway" operations at the Earth-Moon L1 location in a scenario that might involve a Crew Exploration Vehicle (CEV). We assess requirements for that vehicle that would permit such servicing operations. We consider propulsion-economical observatory transfer between L1 and L2, the importance of subsystem modularity, strategies for contamination mitigation and on-orbit integration and test, and the functional relationship of humans and robots, including latency issues for telerobotics. Issues of safety and risk to observatory and personnel are reviewed. Options for in situ servicing at L2 are briefly considered. Opportunities are discussed in the context of value that such an L1 gateway might have to lunar surface efforts and other exploration goals. This work is supported by the NASA Science Mission Directorate.

Lester, D. F.; Moe, R. V.; Derkowski, B. J.; Friedman, E. J.; Espero, T.; Lillie, C. F.

2005-05-01

433

ESSC-ESF Position Paper-Science-Driven Scenario for Space Exploration: Report from the European Space Sciences Committee (ESSC)  

NASA Astrophysics Data System (ADS)

In 2005 the then ESA Directorate for Human Spaceflight, Microgravity and Exploration (D-HME) commissioned a study from the European Science Foundation's (ESF) European Space Sciences Committee (ESSC) to examine the science aspects of the Aurora Programme in preparation for the December 2005 Ministerial Conference of ESA Member States, held in Berlin. A first interim report was presented to ESA at the second stakeholders meeting on 30 and 31 May 2005. A second draft report was made available at the time of the final science stakeholders meeting on 16 September 2005 in order for ESA to use its recommendations to prepare the Executive proposal to the Ministerial Conference. The final ESSC report on that activity came a few months after the Ministerial Conference (June 2006) and attempted to capture some elements of the new situation after Berlin, and in the context of the reduction in NASA's budget that was taking place at that time; e.g., the postponement sine die of the Mars Sample Return mission. At the time of this study, ESSC made it clear to ESA that the timeline imposed prior to the Berlin Conference had not allowed for a proper consultation of the relevant science community and that this should be corrected in the near future. In response to that recommendation, ESSC was asked again in the summer of 2006 to initiate a broad consultation to define a science-driven scenario for the Aurora Programme. This exercise ran between October 2006 and May 2007. ESA provided the funding for staff support, publication costs, and costs related to meetings of a Steering Group, two meetings of a larger ad hoc group (7 and 8 December 2006 and 8 February 2007), and a final scientific workshop on 15 and 16 May 2007 in Athens. As a result of these meetings a draft report was produced and examined by the Ad Hoc Group. Following their endorsement of the report and its approval by the plenary meeting of the ESSC, the draft report was externally refereed, as is now normal practice with all ESSC-ESF reports, and amended accordingly. The Ad Hoc Group defined overarching scientific goals for Europe's exploration programme, dubbed "Emergence and co-evolution of life with its planetary environments," focusing on those targets that can ultimately be reached by humans, i.e., Mars, the Moon, and Near Earth Objects. Mars was further recognized as the focus of that programme, with Mars sample return as the recognized primary goal; furthermore the report clearly states that Europe should position itself as a major actor in defining and leading Mars sample return missions. The report is reproduced in this article. On 26 November 2008 the Ministers of ESA Member States decided to give a high strategic priority to the robotic exploration programme of Mars by funding the enhanced ExoMars mission component, in line therefore with the recommendations from this ESSC-ESF report.

Worms, Jean-Claude; Lammer, Helmut; Barucci, Antonella; Beebe, Reta; Bibring, Jean-Pierre; Blamont, Jacques; Blanc, Michel; Bonnet, Roger; Brucato, John R.; Chassefière, Eric; Coradini, Angioletta; Crawford, Ian; Ehrenfreund, Pascale; Falcke, Heino; Gerzer, Rupert; Grady, Monica; Grande, Manuel; Haerendel, Gerhard; Horneck, Gerda; Koch, Bernhard; Lobanov, Andreï; Lopez-Moreno, José J.; Marco, Robert; Norsk, Peter; Rothery, Dave; Swings, Jean-Pierre; Tropea, Cam; Ulamec, Stephan; Westall, Frances; Zarnecki, John

2009-02-01

434

ESSC-ESF position paper--science-driven scenario for space exploration: report from the European Space Sciences Committee (ESSC).  

PubMed

In 2005 the then ESA Directorate for Human Spaceflight, Microgravity and Exploration (D-HME) commissioned a study from the European Science Foundation's (ESF) European Space Sciences Committee (ESSC) to examine the science aspects of the Aurora Programme in preparation for the December 2005 Ministerial Conference of ESA Member States, held in Berlin. A first interim report was presented to ESA at the second stakeholders meeting on 30 and 31 May 2005. A second draft report was made available at the time of the final science stakeholders meeting on 16 September 2005 in order for ESA to use its recommendations to prepare the Executive proposal to the Ministerial Conference. The final ESSC report on that activity came a few months after the Ministerial Conference (June 2006) and attempted to capture some elements of the new situation after Berlin, and in the context of the reduction in NASA's budget that was taking place at that time; e.g., the postponement sine die of the Mars Sample Return mission. At the time of this study, ESSC made it clear to ESA that the timeline imposed prior to the Berlin Conference had not allowed for a proper consultation of the relevant science community and that this should be corrected in the near future. In response to that recommendation, ESSC was asked again in the summer of 2006 to initiate a broad consultation to define a science-driven scenario for the Aurora Programme. This exercise ran between October 2006 and May 2007. ESA provided the funding for staff support, publication costs, and costs related to meetings of a Steering Group, two meetings of a larger ad hoc group (7 and 8 December 2006 and 8 February 2007), and a final scientific workshop on 15 and 16 May 2007 in Athens. As a result of these meetings a draft report was produced and examined by the Ad Hoc Group. Following their endorsement of the report and its approval by the plenary meeting of the ESSC, the draft report was externally refereed, as is now normal practice with all ESSC-ESF reports, and amended accordingly. The Ad Hoc Group defined overarching scientific goals for Europe's exploration programme, dubbed "Emergence and co-evolution of life with its planetary environments," focusing on those targets that can ultimately be reached by humans, i.e., Mars, the Moon, and Near Earth Objects. Mars was further recognized as the focus of that programme, with Mars sample return as the recognized primary goal; furthermore the report clearly states that Europe should position itself as a major actor in defining and leading Mars sample return missions. The report is reproduced in this article. On 26 November 2008 the Ministers of ESA Member States decided to give a high strategic priority to the robotic exploration programme of Mars by funding the enhanced ExoMars mission component, in line therefore with the recommendations from this ESSC-ESF report. PMID:19203241

Worms, Jean-Claude; Lammer, Helmut; Barucci, Antonella; Beebe, Reta; Bibring, Jean-Pierre; Blamont, Jacques; Blanc, Michel; Bonnet, Roger; Brucato, John R; Chassefière, Eric; Coradini, Angioletta; Crawford, Ian; Ehrenfreund, Pascale; Falcke, Heino; Gerzer, Rupert; Grady, Monica; Grande, Manuel; Haerendel, Gerhard; Horneck, Gerda; Koch, Bernhard; Lobanov, Andreï; Lopez-Moreno, José J; Marco, Roberto; Norsk, Peter; Rothery, Dave; Swings, Jean-Pierre; Tropea, Cam; Ulamec, Stephan; Westall, Frances; Zarnecki, John

435

Explore  

NSDL National Science Digital Library

Offered by the Tata Energy Research Institute, the EduGreen Explore Web site allows kids to learn about energy, water, climate change, solid waste, and more. Besides giving good descriptions on these various subjects, students will also gain a global perspective on these issues since the Institute, which is located in India, gives specific information for the country. The site also contains quizzes, maps, activities, and more worth checking out.

2002-01-01

436

Maximizing Ion Current by Space Charge Neutralization using Negative Ions and Dust Particles  

SciTech Connect

Ion current extracted from an ion source (ion thruster) can be increased above the Child-Langmuir limit if the ion space charge is neutralized. Similarly, the limiting kinetic energy density of the plasma flow in a Hall thruster might be exceeded if additional mechanisms of space charge neutralization are introduced. Space charge neutralization with high-mass negative ions or negatively charged dust particles seems, in principle, promising for the development of a high current or high energy density source of positive light ions. Several space charge neutralization schemes that employ heavy negatively charged particles are considered. It is shown that the proposed neutralization schemes can lead, at best, only to a moderate but nonetheless possibly important increase of the ion current in the ion thruster and the thrust density in the Hall thruster.

A. Smirnov; Y. Raitses; N.J. Fisch

2005-01-25

437

Limitations Of The Current State Space Modelling Approach In Multistage Machining Processes Due To Operation Variations  

NASA Astrophysics Data System (ADS)

The State Space modelling approach has been recently proposed as an engineering-driven technique for part quality prediction in Multistage Machining Processes (MMP). Current State Space models incorporate fixture and datum variations in the multi-stage variation propagation, without explicitly considering common operation variations such as machine-tool thermal distortions, cutting-tool wear, cutting-tool deflections, etc. This paper shows the limitations of the current State Space model through an experimental case study where the effect of the spindle thermal expansion, cutting-tool flank wear and locator errors are introduced. The paper also discusses the extension of the current State Space model to include operation variations and its potential benefits.

Abellán-Nebot, J. V.; Liu, J.; Romero, F.

2009-11-01

438

Maximizing ion current by space-charge neutralization using negative ions and dust particles  

SciTech Connect

Ion current extracted from an ion source (ion thruster) can be increased above the Child-Langmuir limit if the ion space charge is neutralized. Similarly, the limiting kinetic energy density of the plasma flow in a Hall thruster might be exceeded if additional mechanisms of space-charge neutralization are introduced. Space-charge neutralization with high-mass negative ions or negatively charged dust particles seems, in principle, promising for the development of a high current or high energy density source of positive light ions. Several space-charge neutralization schemes that employ heavy negatively charged particles are considered. It is shown that the proposed neutralization schemes can lead, at best, only to a moderate but nonetheless possibly important increase of the ion current in the ion thruster and the thrust density in the Hall thruster.

Smirnov, A.; Raitses, Y.; Fisch, N.J. [Princeton University Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543 (United States)

2005-05-15

439

Considering the Ethical Implications of Space Exploration and Potential Impacts on Planetary Environments and Possible Indigenous Life  

NASA Astrophysics Data System (ADS)

Since the early days of the Outer Space Treaty, a primary concern of planetary protection policy has been to avoid contamination of planetary environments by terrestrial microbes that could compromise current or subsequent scientific investigations, particularly those searching for indigenous life. Over the past decade robotic missions and astrobiological research have greatly increased our understanding of diverse planetary landscapes and altered our views about the survivability of terrestrial organisms in extreme environments. They have also expanded notions about the prospect for finding evidence of extraterrestrial life. Recently a number of different groups, including the COSPAR Planetary Protection Workshop in Montreal (January 2008), have questioned whether it is advisable to re-examine current<