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1

Atmosphere Explorer (AE) spacecraft system description  

NASA Technical Reports Server (NTRS)

The principal design and performance characteristics of the AE spacecraft system designed to support the Atmosphere Explorer C, D, and E missions are summarized. It has been prepared for the information of experimenters and other participants in the Atmosphere Explorer program as a general guide for design and operational planning. The description represents the spacecraft system as defined at the conclusion of the interface definition study.

1972-01-01

2

Automated Estimating System (AES)  

SciTech Connect

This document describes Version 3.1 of the Automated Estimating System, a personal computer-based software package designed to aid in the creation, updating, and reporting of project cost estimates for the Estimating and Scheduling Department of the Martin Marietta Energy Systems Engineering Division. Version 3.1 of the Automated Estimating System is capable of running in a multiuser environment across a token ring network. The token ring network makes possible services and applications that will more fully integrate all aspects of information processing, provides a central area for large data bases to reside, and allows access to the data base by multiple users. Version 3.1 of the Automated Estimating System also has been enhanced to include an Assembly pricing data base that may be used to retrieve cost data into an estimate. A WBS Title File program has also been included in Version 3.1. The WBS Title File program allows for the creation of a WBS title file that has been integrated with the Automated Estimating System to provide WBS titles in update mode and in reports. This provides for consistency in WBS titles and provides the capability to display WBS titles on reports generated at a higher WBS level.

Holder, D.A.

1989-09-01

3

AE-5 end of mission tests report. [Explorer 55 satellite  

NASA Technical Reports Server (NTRS)

A spin up test and a TDRS tracking simulation were performed on the AE-5 spacecraft before its end of mission. the spin up test showed that the Body Horizon Scanner could be successfully used on other spacecraft with spin rates up to 10 RPM. the TDRS tracking simulation showed that an AE-5 type attitude control system could be successfully used to point the spacecraft towards a TDRS for the purpose of transmitting/relaying data via the TDRS.

Stengle, T. H.; Kissel, F.; Schaefer, J.; Kalil, F.

1981-01-01

4

Development of Carbon Dioxide Removal Systems for Advanced Exploration Systems.  

National Technical Information Service (NTIS)

NASA's Advanced Exploration Systems (AES) program is pioneering new approaches for rapidly developing prototype systems, demonstrating key capabilities, and validating operational concepts for future human missions beyond Earth orbit (NASA 2012). These fo...

D. Trinh D. Watson E. King E. M. Mattox J. Thomas J. C. Knox R. Gostowski

2012-01-01

5

An expert system program for ICP-AES system diagnosis  

NASA Astrophysics Data System (ADS)

This article is an electronic publication in Spectrochimica Acta Electronica (SAE), the electronic section of Spectrochimica Acta Part B (SAB). The hardcopy text is accompanied by two diskettes containing the installation program for the application. The main article discusses the purpose of this work and the Appendix provides instructions on the use of the program. ICP-AES performance can be followed by monitoring a series of atomic lines. QUID Expert is a Windows based program which uses line intensities from a standard solution in conjunction with a series of rules to determine when an ICP-AES is degrading and where the probable fault lies. The software provides other features such as a logbook and automatic recording to allow users to monitor system performance over extended times. In the tradition of modern expert systems, QUID Expert provides guidance as to what possible fault(s) might be present in the system and recommends remedial action(s).

Sartoros, Christine; Alary, Jean-François; Salin, Eric D.; Mermet, Jean-Michel

1997-11-01

6

An expert system program for ICP-AES system diagnosis  

Microsoft Academic Search

This article is an electronic publication in Spectrochimica Acta Electronica (SAE), the electronic section of Spectrochimica Acta Part B (SAB). The hardcopy text is accompanied by two diskettes containing the installation program for the application. The main article discusses the purpose of this work and the Appendix provides instructions on the use of the program. ICP-AES performance can be followed

Christine Sartoros; Jean-François Alary; Eric D. Salin; Jean-Michel Mermet

1997-01-01

7

The near-wake structure of the Atmosphere Explorer C /AE-C/ satellite - A parametric investigation  

NASA Technical Reports Server (NTRS)

Measurements of ion current, electron temperature, and values of space potential obtained from the cylindrical electrostatic probe on board the Atmosphere Explorer C (AE-C) satellite were used to examine, in a parametric manner, the angular distribution of charge around the satellite. Interest is focused on nighttime equatorial data in the altitude range 275-620 km, which yields a wide range for the parameter R sub D (the radius of the satellite divided by the ambient value of the Debye lengths), including R sub D greater than 100, which is of practical significance to large space platforms. The variations of normalized ion current in the wake zone of the AE-C satellite appear to display an exponential dependence on R sub D for 'constant' values of other relevant parameters. The angular variations of electron temperature and space potential in the close vicinity of the satellite's surface were examined and compared with results from the Explorer 31 satellite. The variation of the ratio of measured to computed space potential with electron temperature was examined using data from both the AE-C and Explorer 31 satellites. It was found that the ratio is greater than unity. Possible causes for the above inequality are discussed.

Samir, U.; Gordon, R.; Brace, L.; Theis, R.

1979-01-01

8

Solar System Exploration  

NSDL National Science Digital Library

Solar System Exploration, a NASA Office of Space Science site, is dedicated to information about the exploration of our solar system. Press releases, latest images, and late breaking astronomy news discuss the most up-to-date knowledge. The planets section has facts about all nine planets, as well as a comparative data table (for mass, orbit, volume, density, rotation, etc.). Each planet is described in detail, and links to additional information are given. The missions section highlights the dates, objectives, and general overview about each spacecraft. There is also a technology and research section, as well as a timeline illustrating the history of space exploration.

9

Optimal exploration systems  

NASA Astrophysics Data System (ADS)

This dissertation studies optimal exploration, defined as the collection of information about given objects of interest by a mobile agent (the explorer) using imperfect sensors. The key aspects of exploration are kinematics (which determine how the explorer moves in response to steering commands), energetics (which determine how much energy is consumed by motion and maneuvers), informatics (which determine the rate at which information is collected) and estimation (which determines the states of the objects). These aspects are coupled by the steering decisions of the explorer. We seek to improve exploration by finding trade-offs amongst these couplings and the components of exploration: the Mission, the Path and the Agent. A comprehensive model of exploration is presented that, on one hand, accounts for these couplings and on the other hand is simple enough to allow analysis. This model is utilized to pose and solve several exploration problems where an objective function is to be minimized. Specific functions to be considered are the mission duration and the total energy. These exploration problems are formulated as optimal control problems and necessary conditions for optimality are obtained in the form of two-point boundary value problems. An analysis of these problems reveals characteristics of optimal exploration paths. Several regimes are identified for the optimal paths including the Watchtower, Solar and Drag regime, and several non-dimensional parameters are derived that determine the appropriate regime of travel. The so-called Power Ratio is shown to predict the qualitative features of the optimal paths, provide a metric to evaluate an aircrafts design and determine an aircrafts capability for flying perpetually. Optimal exploration system drivers are identified that provide perspective as to the importance of these various regimes of flight. A bank-to-turn solar-powered aircraft flying at constant altitude on Mars is used as a specific platform for analysis using the coupled model. Flight-paths found with this platform are presented that display the optimal exploration problem characteristics. These characteristics are used to form heuristics, such as a Generalized Traveling Salesman Problem solver, to simplify the exploration problem. These heuristics are used to empirically show the successful completion of an exploration mission by a physical explorer.

Klesh, Andrew T.

10

Solar system exploration  

NASA Technical Reports Server (NTRS)

The goal of planetary exploration is to understand the nature and development of the planets, as illustrated by pictures from the first two decades of spacecraft missions and by the imaginations of space artists. Planets, comets, asteroids, and moons are studied to discover the reasons for their similarities and differences and to find clues that contain information about the primordial process of planet origins. The scientific goals established by the National Academy of Sciences as the foundation of NASA's Solar System Exploration Program are covered: to determine the nature of the planetary system, to understand its origin and evolution, the development of life on Earth, and the principles that shape present day Earth.

Chapman, Clark R.; Ramlose, Terri (editor)

1989-01-01

11

Automated Estimating System (AES) version 6.0 - user`s manual. Revision 5  

SciTech Connect

This document describes Version 6.0 of the Automated Estimating System (AES), a personal computer-based software package. The AES is designed to aid in the creation, updating, and reporting of project cost estimates for the Estimating and Scheduling Engineering Department of Central Engineering Services of Martin Marietta Energy Systems, Inc. AES provides formatted input screens to guide the user through the estimate creation/update process and provides several standardized reports that allow cost to be sorted and summarized in many different formats and at several levels of aggregation.

Holder, D.A.; Schwarz, R.K. [ed.

1994-06-01

12

Automated Estimating System (AES): Version 6.1: User`s manual. Revision 6  

SciTech Connect

This document describes Version 6.1 of the Automated Estimating System (AES), a personal computer-based software package. The AES is designed to aid in the creation, updating, and reporting of project cost estimates for the Estimating and Scheduling Engineering Department of Central Engineering Services of Lockheed Martin Energy Systems,Inc. AES provides formatted input screens to guide the user through the estimate creation/update process and provides several standardized reports that allow cost to be sorted and summarized in many different formats and at several levels of aggregation.

Schwarz, R.K. [ed.; Holder, D.A.

1996-03-01

13

Ultrasonic fatigue process analyzed by using LVD and continuous ae waveform analysis system  

NASA Astrophysics Data System (ADS)

Non-linear ultrasonic parameter ? and acoustic emission signals of ultrasonic fatigue testing were analyzed by using Laser Doppler Vibrometer and continuous AE waveform analysis system. Notched specimens of the high-strength low-alloy steel were prepared for the ultrasonic fatigue testing with exciting vibration frequency of 20 kHz. The AE events for each broken specimens were detected prior to the increase of ? parameter.

Shiwa, M.; Furuya, Y.; Yamawaki, H.; Ito, K.; Enoki, M.

2012-05-01

14

Seismic exploration system improvement  

SciTech Connect

This patent describes a seismic exploration system having geophone locations along a survey line with at least one geophone connected to separate circuits connected to corresponding terminals of a roll-along common depth point switch. A means is described for identifying a specific one of the geophone locations as the switch changes connections, comprising means for superimposing a signal outside the useful range of seismic energy signals generated by the geophones on the one of the separate circuits connected to the specific geophone location whereby the location may be identified on the changed connection side of the switch.

Bearden, J.M.

1987-01-06

15

Exploration Medical System Demonstration  

NASA Technical Reports Server (NTRS)

BACKGROUND: Exploration class missions will present significant new challenges and hazards to the health of the astronauts. Regardless of the intended destination, beyond low Earth orbit a greater degree of crew autonomy will be required to diagnose medical conditions, develop treatment plans, and implement procedures due to limited communications with ground-based personnel. SCOPE: The Exploration Medical System Demonstration (EMSD) project will act as a test bed on the International Space Station (ISS) to demonstrate to crew and ground personnel that an end-to-end medical system can assist clinician and non-clinician crew members in optimizing medical care delivery and data management during an exploration mission. Challenges facing exploration mission medical care include limited resources, inability to evacuate to Earth during many mission phases, and potential rendering of medical care by non-clinicians. This system demonstrates the integration of medical devices and informatics tools for managing evidence and decision making and can be designed to assist crewmembers in nominal, non-emergent situations and in emergent situations when they may be suffering from performance decrements due to environmental, physiological or other factors. PROJECT OBJECTIVES: The objectives of the EMSD project are to: a. Reduce or eliminate the time required of an on-orbit crew and ground personnel to access, transfer, and manipulate medical data. b. Demonstrate that the on-orbit crew has the ability to access medical data/information via an intuitive and crew-friendly solution to aid in the treatment of a medical condition. c. Develop a common data management framework that can be ubiquitously used to automate repetitive data collection, management, and communications tasks for all activities pertaining to crew health and life sciences. d. Ensure crew access to medical data during periods of restricted ground communication. e. Develop a common data management framework that allows for scalability, extensibility, and interoperability of data sources and data users. f. Lower total cost of ownership for development and sustainment of peripheral hardware and software that use EMSD for data management. g. Provide a better standard of healthcare for crew members through reductions in the time required by crew and ground personnel to provide medical treatment and the number of crew errors experienced during treatment.

Rubin, D. A.; Watkins, S. D.

2014-01-01

16

Advanced Exploration Systems Water Architecture Study Interim Results  

NASA Technical Reports Server (NTRS)

The mission of the Advanced Exploration System (AES) Water Recovery Project (WRP) is to develop advanced water recovery systems that enable NASA human exploration missions beyond low Earth orbit (LEO). The primary objective of the AES WRP is to develop water recovery technologies critical to near-term missions beyond LEO. The secondary objective is to continue to advance mid-readiness-level technologies to support future NASA missions. An effort is being undertaken to establish the architecture for the AES Water Recovery System (WRS) that meets both near- and long-term objectives. The resultant architecture will be used to guide future technical planning, establish a baseline development roadmap for technology infusion, and establish baseline assumptions for integrated ground and on-orbit Environmental Control and Life Support Systems definition. This study is being performed in three phases. Phase I established the scope of the study through definition of the mission requirements and constraints, as well as identifying all possible WRS configurations that meet the mission requirements. Phase II focused on the near-term space exploration objectives by establishing an International Space Station-derived reference schematic for long-duration (>180 day) in-space habitation. Phase III will focus on the long-term space exploration objectives, trading the viable WRS configurations identified in Phase I to identify the ideal exploration WRS. The results of Phases I and II are discussed in this paper.

Sargusingh, Miriam J.

2013-01-01

17

Exploration geochemical technique for the determination of preconcentrated organometallic halides by ICP-AES  

USGS Publications Warehouse

An atomic absorption extraction technique which is widely used in geochemical exploration for the determination of Ag, As, Au, Bi, Cd, Cu, Mo, Pb, Sb, and Zn has been modified and adapted to a simultaneous inductively coupled plasma-atomic emission instrument. the experimental and operating parameters are described for the preconcentration of the metals into their organometallic halides and for the determination of the metals. Lower limits of determination are equal to or improved over those for flame atomic absorption (except Au) and ICP results are very similar to the accepted AA values, with precision for the ICP data in excess of that necessary for exploration purposes.

Motooka, J. M.

1988-01-01

18

Automated Estimating System (AES), Standard Value Update Program, user`s manual  

SciTech Connect

This manual contains instructions for operating the Standard Value Update Program. This program is operated and controlled by selected individuals in the Estimating and Scheduling Engineering Department of the Martin Marietta Energy Systems, Inc., Engineering Division. It is used to control and standardized input into the Automated Estimating System (AES) Estimating program, a person computer-based software package designed to aid in the creation, updating, and reporting of project cost estimates. The AES Estimating program is documented in a separate user`s manual.

Schwartz, R.K. [ed.; Holder, D.A.

1994-08-01

19

iPAS: AES Flight System Technology Maturation for Human Spaceflight  

NASA Technical Reports Server (NTRS)

In order to realize the vision of expanding human presence in space, NASA will develop new technologies that can enable future crewed spacecraft to go far beyond Earth orbit. These technologies must be matured to the point that future project managers can accept the risk of incorporating them safely and effectively within integrated spacecraft systems, to satisfy very challenging mission requirements. The technologies must also be applied and managed within an operational context that includes both on-board crew and mission support on Earth. The Advanced Exploration Systems (AES) Program is one part of the NASA strategy to identify and develop key capabilities for human spaceflight, and mature them for future use. To support this initiative, the Integrated Power Avionics and Software (iPAS) environment has been developed that allows engineers, crew, and flight operators to mature promising technologies into applicable capabilities, and to assess the value of these capabilities within a space mission context. This paper describes the development of the integration environment to support technology maturation and risk reduction, and offers examples of technology and mission demonstrations executed to date.

Othon, William L.

2014-01-01

20

Exploration Systems Town Hall Meeting  

NASA Video Gallery

Doug Cooke, Associate Administrator for NASA's Exploration Systems Mission Directorate, discusses the future during a question and answer session with employees at NASA Headquarters on April 19, 2010.

21

NASA: Solar System Exploration  

NSDL National Science Digital Library

This NASA website offers a wide variety of space science-related activities, multimedia, and facts for people of all ages. The website presents the latest news and upcoming space science events. Students and educators can explore space missions by name, decade, target, and nation. In the Science and Technology link, visitors can find the latest science and technology features, NASA science highlights, as well as information about astrobiology and power and propulsion. Kids will enjoy the Alien Safari interactive module and interesting facts about the planets. Teachers can easily locate activities about the science behind the latest NASA headlines through the Fast Lesson Finder. Everyone can view the images and videos of the planets, spacecraft, technology, and additional subjects.

2006-01-10

22

Data exploration systems for databases  

NASA Technical Reports Server (NTRS)

Data exploration systems apply machine learning techniques, multivariate statistical methods, information theory, and database theory to databases to identify significant relationships among the data and summarize information. The result of applying data exploration systems should be a better understanding of the structure of the data and a perspective of the data enabling an analyst to form hypotheses for interpreting the data. This paper argues that data exploration systems need a minimum amount of domain knowledge to guide both the statistical strategy and the interpretation of the resulting patterns discovered by these systems.

Greene, Richard J.; Hield, Christopher

1992-01-01

23

Development of Carbon Dioxide Removal Systems for Advanced Exploration Systems  

NASA Technical Reports Server (NTRS)

"NASA's Advanced Exploration Systems (AES) program is pioneering new approaches for rapidly developing prototype systems, demonstrating key capabilities, and validating operational concepts for future human missions beyond Earth orbit" (NASA 2012). These forays beyond the confines of earth's gravity will place unprecedented demands on launch systems. They must not only blast out of earth's gravity well as during the Apollo moon missions, but also launch the supplies needed to sustain a crew over longer periods for exploration missions beyond earth's moon. Thus all spacecraft systems, including those for the separation of metabolic carbon dioxide and water from a crewed vehicle, must be minimized with respect to mass, power, and volume. Emphasis is also placed on system robustness both to minimize replacement parts and ensure crew safety when a quick return to earth is not possible. Current efforts are focused on improving the current state-of-the-art systems utilizing fixed beds of sorbent pellets by seeking more robust pelletized sorbents, evaluating structured sorbents, and examining alternate bed configurations to improve system efficiency and reliability. These development efforts combine testing of sub-scale systems and multi-physics computer simulations to evaluate candidate approaches, select the best performing options, and optimize the configuration of the selected approach, which is then implemented in a full-scale integrated atmosphere revitalization test. This paper describes the carbon dioxide (CO2) removal hardware design and sorbent screening and characterization effort in support of the Atmosphere Resource Recovery and Environmental Monitoring (ARREM) project within the AES program. A companion paper discusses development of atmosphere revitalization models and simulations for this project.

Knox, James C.; Trinh, Diep; Gostowski, Rudy; King, Eric; Mattox, Emily M.; Watson, David; Thomas, John

2012-01-01

24

Strong Authentication for RFID Systems Using the AES Algorithm  

Microsoft Academic Search

Radio frequency identification (RFID) is an emerging technology which brings enormous productivity benefits in applications where objects have to be identified automatically. This paper presents issues concerning security and privacy of RFID systems which are heavily discussed in public. In contrast to the RFID community, which claims that cryptographic components are too costly for RFID tags, we describe a solution

Martin Feldhofer; Sandra Dominikus; Johannes Wolkerstorfer

2004-01-01

25

AES Security Protocol Implementation for Automobile Remote Keyless System  

Microsoft Academic Search

The remote keyless system is widely used in automobile industry to lock or unlock the automobile's door, trunk, and start the ignition. It comprises a handheld key fob to be held by the driver and a set of radio transceiver devices located in the automobile. Operation commands are represented by strings of wireless signal transmitted between the key fob and

Xiao Ni; Weiren Shi; V. F. S. Fook

2007-01-01

26

Exploring the Systems in Ecosystems  

NSDL National Science Digital Library

In this media-rich lesson, students use a systems thinking approach to explore the components and processes of ecosystems. They analyze both a hypothetical and a local ecosystem by identifying abiotic and biotic components and their relationships.

Foundation, Wgbh E.

2007-08-09

27

Exobiology in Solar System Exploration  

NASA Technical Reports Server (NTRS)

A symposium, 'Exobiology in Solar System Exploration,' was held on 24-26 Aug. 1988. The symposium provided an in-depth investigation of the role of Exobiology in solar system exploration. It is expected that the symposium will provide direction for future participation of the Exobiology community in solar system exploration and alert the Planetary community to the continued importance of an Exobiology Flight Program. Although the focus of the symposium was primarily on Exobiology in solar system exploration missions, several ground based and Earth-orbital projects such as the Search for Extraterrestrial Intelligence, Gas Grain Facility, and Cosmic Dust Collection Facility represent upcoming research opportunities planned to accommodate the goals and objectives of the Exobiology community as well. This report contains papers for all but one of the presentations given at the symposium.

Carle, Glenn C. (editor); Schwartz, Deborah E. (editor); Huntington, Judith L. (editor)

1992-01-01

28

Fission Systems for Mars Exploration  

NASA Technical Reports Server (NTRS)

Fission systems are used extensively on earth, and 34 such systems have flown in space. The energy density of fission is over 10 million times that of chemical reactions, giving fission the potential to eliminate energy density constraints for many space missions. Potential safety and operational concerns with fission systems are well understood, and strategies exist for affordably developing such systems. By enabling a power-rich environment and highly efficient propulsion, fission systems could enable affordable, sustainable exploration of Mars.

Houts, Michael G.; Kim, T.; Dorney, D. J.; Swint, Marion Shayne

2012-01-01

29

The Exploration Water Recovery System  

NASA Technical Reports Server (NTRS)

The Exploration Water Recovery System is designed towards fulfillment of NASA s Vision for Space Exploration, which will require elevation of existing technologies to higher levels of optimization. This new system, designed for application to the Exploration infrastructure, presents a novel combination of proven air and water purification technologies. The integration of unit operations is modified from that of the current state-of-the-art water recovery system so as to optimize treatment of the various waste water streams, contaminant loads, and flow rates. Optimization is achieved primarily through the removal of volatile organic contaminants from the vapor phase prior to their absorption into the liquid phase. In the current state-of-the-art system, the water vapor in the cabin atmosphere is condensed, and the volatile organic contaminants present in that atmosphere are absorbed into the aqueous phase. Removal of contaminants the5 occurs via catalytic oxidation in the liquid phase. Oxidation kinetics, however, dictate that removal of volatile organic contaminants from the vapor phase can inherently be more efficient than their removal from the aqueous phase. Taking advantage of this efficiency reduces the complexity of the water recovery system. This reduction in system complexity is accompanied by reductions in the weight, volume, power, and resupply requirements of the system. Vapor compression distillation technology is used to treat the urine, condensate, and hygiene waste streams. This contributes to the reduction in resupply, as incorporation of vapor compression distillation technology at this point in the process reduces reliance on the expendable ion exchange and adsorption media used in the current state-of-the-art water recovery system. Other proven technologies that are incorporated into the Exploration Water Recovery System include the Trace Contaminant Control System and the Volatile Removal Assembly.

ORourke, Mary Jane E.; Carter, Layne; Holder, Donald W.; Tomes, Kristin M.

2006-01-01

30

MET3-AE system to support management of pediatric asthma exacerbation in the emergency department.  

PubMed

A decision making process behind the management of pediatric patients with asthma exacerbations in the Emergency Department includes three stages: data collection, diagnosis formulation and treatment planning. These stages are associated with activities involving different types of clinical knowledge: factual, conceptual and procedural. Effective decision support should span over the entire decision making process and facilitate the use of diversified clinical knowledge. In this paper we present MET3-AE - a point of care decision support system that satisfies this requirement. The system helps emergency physician collect data, evaluate exacerbation severity, plan corresponding treatment and retrieve clinical evidence associated with a given treatment plan. It was developed using ontology-driven and multi-agent methodologies and implemented with open source software. The system is accessible on tablet and desktop computers and smartphones, and it interacts with other hospital information systems. It was successfully verified in a simulated clinical setting and now it is undergoing testing in a teaching hospital. PMID:20841804

Wilk, Szymon; Michalowski, Wojtek; Farion, Ken; Sayyad Shirabad, Jelber

2010-01-01

31

A first arrival identification system of acoustic emission (AE) signals by means of a high-order statistics approach  

NASA Astrophysics Data System (ADS)

One of the fundamental problems in non-destructive testing and geophysics is the precise determination of the first arrival of acoustic emission (AE) signals (or seismic signals) recorded by multi-channel systems. The knowledge of this time is very important, mainly in the case of automatic localization of individual AE events. Several approaches are routinely used in practice such as crossing of the threshold level, analysis of the LTA/STA (long-time average/short-time average), etc. In our paper, an approach based on high-order statistics (HOS) that is able to carry out precise arrival time determination without human intervention is presented. The approach was tested on real AE data recorded by an eight-channel recording system. This simple, accurate and quite fast method is predetermined to be used in automatic processing of transient waveform data from acoustic emission, seismic signals, ultrasonic sounding, etc.

Lokajícek, T.; Klíma, K.

2006-09-01

32

Learning by exploration: Thinking aloud while exploring an information system  

Microsoft Academic Search

The aim of the current research is to examine the ability of people to learn a computer system by exploration and to asses the efficacy of a user interface with properties that are supposed to support exploration. The study described in this paper used the think-aloud method to obtain detailed information about the goals of the user and their realization

HERRE VAN OOSTENDORP; SJAAK DE MUL

1999-01-01

33

AES Water Architecture Study Interim Results  

NASA Technical Reports Server (NTRS)

The mission of the Advanced Exploration System (AES) Water Recovery Project (WRP) is to develop advanced water recovery systems in order to enable NASA human exploration missions beyond low earth orbit (LEO). The primary objective of the AES WRP is to develop water recovery technologies critical to near term missions beyond LEO. The secondary objective is to continue to advance mid-readiness level technologies to support future NASA missions. An effort is being undertaken to establish the architecture for the AES Water Recovery System (WRS) that meets both near and long term objectives. The resultant architecture will be used to guide future technical planning, establish a baseline development roadmap for technology infusion, and establish baseline assumptions for integrated ground and on-orbit environmental control and life support systems (ECLSS) definition. This study is being performed in three phases. Phase I of this study established the scope of the study through definition of the mission requirements and constraints, as well as indentifying all possible WRS configurations that meet the mission requirements. Phase II of this study focused on the near term space exploration objectives by establishing an ISS-derived reference schematic for long-duration (>180 day) in-space habitation. Phase III will focus on the long term space exploration objectives, trading the viable WRS configurations identified in Phase I to identify the ideal exploration WRS. The results of Phases I and II are discussed in this paper.

Sarguisingh, Miriam J.

2012-01-01

34

Exploration Medical System Demonstration Project  

NASA Technical Reports Server (NTRS)

A near-Earth Asteroid (NEA) mission will present significant new challenges including hazards to crew health created by exploring a beyond low earth orbit destination, traversing the terrain of asteroid surfaces, and the effects of variable gravity environments. Limited communications with ground-based personnel for diagnosis and consultation of medical events require increased crew autonomy when diagnosing conditions, creating treatment plans, and executing procedures. Scope: The Exploration Medical System Demonstration (EMSD) project will be a test bed on the International Space Station (ISS) to show an end-to-end medical system assisting the Crew Medical Officers (CMO) in optimizing medical care delivery and medical data management during a mission. NEA medical care challenges include resource and resupply constraints limiting the extent to which medical conditions can be treated, inability to evacuate to Earth during many mission phases, and rendering of medical care by a non-clinician. The system demonstrates the integration of medical technologies and medical informatics tools for managing evidence and decision making. Project Objectives: The objectives of the EMSD project are to: a) Reduce and possibly eliminate the time required for a crewmember and ground personnel to manage medical data from one application to another. b) Demonstrate crewmember's ability to access medical data/information via a software solution to assist/aid in the treatment of a medical condition. c) Develop a common data management architecture that can be ubiquitously used to automate repetitive data collection, management, and communications tasks for all crew health and life sciences activities. d) Develop a common data management architecture that allows for scalability, extensibility, and interoperability of data sources and data users. e) Lower total cost of ownership for development and sustainment of peripheral hardware and software that use EMSD for data management f) Provide better crew health via the reduction in crew errors, crew time, and ground time.

Chin, D. A.; McGrath, T. L.; Reyna, B.; Watkins, S. D.

2011-01-01

35

Biotechnology for Solar System Exploration  

NASA Astrophysics Data System (ADS)

With the advent of a new era of astrobiology missions in the exploration of the solar system and the search for evidence of life elsewhere, we present a new approach to this goal, the integration of biotechnology. We have reviewed the current list of biotechnology techniques, which are applicable to miniaturization, automatization and integration into a combined flight platform. Amongst the techniques reviewed are- The uses of antibodies- Fluorescent detection strategies- Protein and DNA chip technology- Surface plasmon resonance and its relation to other techniques- Micro electronic machining (MEMS where applicable to biologicalsystems)- nanotechnology (e.g. molecular motors)- Lab-on-a-chip technology (including PCR)- Mass spectrometry (i.e. MALDI-TOF)- Fluid handling and extraction technologies- Chemical Force Microscopy (CFM)- Raman Spectroscopy We have begun to integrate this knowledge into a single flight instrument approach for the sole purpose of combining several mutually confirming tests for life, organic and/or microbial contamination, as well as prebiotic and abiotic organic chemicals. We will present several innovative designs for new instrumentation including pro- engineering design drawings of a protein chip reader for space flight and fluid handling strategies. We will also review the use of suitable extraction methodologies for use on different solar system bodies.

Steele, A.; Maule, J.; Toporski, J.; Parro-Garcia, V.; Briones, C.; Schweitzer, M.; McKay, D.

36

76 FR 4089 - Proposed Information Collection; Comment Request; Automated Export System (AES) Program  

Federal Register 2010, 2011, 2012, 2013

...the reporting of export trade information, customer service, compliance with and enforcement of export laws, and provide paperless reports of export information. The AES also enables the U.S. Government to increase its ability to prevent the...

2011-01-24

37

NASA Center for Intelligent Robotic Systems for Space Exploration  

NASA Technical Reports Server (NTRS)

NASA's program for the civilian exploration of space is a challenge to scientists and engineers to help maintain and further develop the United States' position of leadership in a focused sphere of space activity. Such an ambitious plan requires the contribution and further development of many scientific and technological fields. One research area essential for the success of these space exploration programs is Intelligent Robotic Systems. These systems represent a class of autonomous and semi-autonomous machines that can perform human-like functions with or without human interaction. They are fundamental for activities too hazardous for humans or too distant or complex for remote telemanipulation. To meet this challenge, Rensselaer Polytechnic Institute (RPI) has established an Engineering Research Center for Intelligent Robotic Systems for Space Exploration (CIRSSE). The Center was created with a five year $5.5 million grant from NASA submitted by a team of the Robotics and Automation Laboratories. The Robotics and Automation Laboratories of RPI are the result of the merger of the Robotics and Automation Laboratory of the Department of Electrical, Computer, and Systems Engineering (ECSE) and the Research Laboratory for Kinematics and Robotic Mechanisms of the Department of Mechanical Engineering, Aeronautical Engineering, and Mechanics (ME,AE,&M), in 1987. This report is an examination of the activities that are centered at CIRSSE.

1990-01-01

38

The mass ratio and formation mechanisms of Herbig Ae/Be star binary systems  

NASA Astrophysics Data System (ADS)

We present B- and R-band spectroastrometry of a sample of 45 Herbig Ae/Be (HAe/Be) stars in order to study their binary properties. All but one of the targets known to be binary systems with a separation of ~0.1-2.0 arcsec are detected by a distinctive spectroastrometric signature. Some objects in the sample exhibit spectroastrometric features that do not appear attributable to a binary system. We find that these may be due to light reflected from dusty haloes or material entrained in winds. We present eight new binary detections and four detections of an unknown component in previously discovered binary systems. The data confirm previous reports that HAe/Be stars have a high binary fraction, 74 +/- 6 per cent in the sample presented here. We use a spectroastrometric deconvolution technique to separate the spatially unresolved binary spectra into the individual constituent spectra. The separated spectra allow us to ascertain the spectral type of the individual binary components, which in turn allows the mass ratio of these systems to be determined. In addition, we appraise the method used and the effects of contaminant sources of flux. We find that the distribution of system mass ratios is inconsistent with random pairing from the initial mass function, and that this appears robust despite a detection bias. Instead, the mass ratio distribution is broadly consistent with the scenario of binary formation via disc fragmentation. Based on observations made with the William Herschel Telescope (WHT) and the Isaac Newton Telescope (INT) operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias. E-mail: pyhew@leeds.ac.uk

Wheelwright, H. E.; Oudmaijer, R. D.; Goodwin, S. P.

2010-01-01

39

Venus Exploration opportunities within NASA's Solar System Exploration roadmap  

NASA Technical Reports Server (NTRS)

Science goals to understand the origin, history and environment of Venus have been driving international space exploration missions for over 40 years. Past missions include the Magellan and Pioneer-Venus missions by the US; the Venera program by the USSR; and the Vega missions through international cooperation. Furthermore, the US National Research Council (NRC), in the 2003 Solar System Exploration (SSE) Decadal Survey, identified Venus as a high priority target, thus demonstrating a continuing interest in Earth's sister planet. In response to the NRC recommendation, the 2005 NASA SSE Roadmap included a number of potential Venus missions arching through all mission classes from small Discovery, to medium New Frontiers and to large Flagship class missions. While missions in all of these classes could be designed as orbiters with remote sensing capabilities, the desire for scientific advancements beyond our current knowledge - including what we expect to learn from the ongoing ESA Venus Express mission - point to in-situ exploration of Venus.

Balint, Tibor; Thompson, Thomas; Cutts, James; Robinson, James

2006-01-01

40

SIM_EXPLORE: Software for Directed Exploration of Complex Systems  

NASA Technical Reports Server (NTRS)

Physics-based numerical simulation codes are widely used in science and engineering to model complex systems that would be infeasible to study otherwise. While such codes may provide the highest- fidelity representation of system behavior, they are often so slow to run that insight into the system is limited. Trying to understand the effects of inputs on outputs by conducting an exhaustive grid-based sweep over the input parameter space is simply too time-consuming. An alternative approach called "directed exploration" has been developed to harvest information from numerical simulators more efficiently. The basic idea is to employ active learning and supervised machine learning to choose cleverly at each step which simulation trials to run next based on the results of previous trials. SIM_EXPLORE is a new computer program that uses directed exploration to explore efficiently complex systems represented by numerical simulations. The software sequentially identifies and runs simulation trials that it believes will be most informative given the results of previous trials. The results of new trials are incorporated into the software's model of the system behavior. The updated model is then used to pick the next round of new trials. This process, implemented as a closed-loop system wrapped around existing simulation code, provides a means to improve the speed and efficiency with which a set of simulations can yield scientifically useful results. The software focuses on the case in which the feedback from the simulation trials is binary-valued, i.e., the learner is only informed of the success or failure of the simulation trial to produce a desired output. The software offers a number of choices for the supervised learning algorithm (the method used to model the system behavior given the results so far) and a number of choices for the active learning strategy (the method used to choose which new simulation trials to run given the current behavior model). The software also makes use of the LEGION distributed computing framework to leverage the power of a set of compute nodes. The approach has been demonstrated on a planetary science application in which numerical simulations are used to study the formation of asteroid families.

Burl, Michael; Wang, Esther; Enke, Brian; Merline, William J.

2013-01-01

41

Geologic exploration of solar system  

Microsoft Academic Search

The processes that must have operated on the early Earth have been deduced from evidence from ancient surfaces of the Moon and planets. In particular, such comparative studies have demonstrated that only two geologic processes have been widespread throughout the history of the solar system: impact cratering and volcanism. Impact craters have formed throughout solar system history, indeed the planets

Wood

1987-01-01

42

Water Recovery Systems for Exploration Missions  

NASA Technical Reports Server (NTRS)

As NASA prepares for the Vision for Space Exploration, advances in technology for water recovery systems are necessary to enable future missions. This paper examines the proposed water recovery systems for the initial Constellation exploration missions as well as the capability gaps that exist in the current technology portfolio. We discuss how these gaps will be addressed with future technology development. In addition, the paper reviews how the water recovery system matures throughout the sequence of planned exploration missions, to ultimately support a 180-day lunar mission.

Pickering, Karen D.

2007-01-01

43

Space exploration of the solar system  

Microsoft Academic Search

A brief review of the current situation of space exploration of the solar system is presented. Particular attention is given to the meaning, object, scheme and achievements in the exploration of the Moon, Mars, asteroids and outer planets. The future space missions of NASA, ESA, Russia and Japan are also outlined.

Daohan Chen

1999-01-01

44

Exploration Medical System Demonstration (EMSD) Project.  

National Technical Information Service (NTIS)

The Exploration Medical System Demonstration (EMSD) is a project under the Exploration Medical Capability (ExMC) element managed by the Human Research Program (HRP). The vision for the EMSD is to utilize ISS as a test bed to show that several medical tech...

D. Chin

2012-01-01

45

Bio-Inspired Engineering of Exploration Systems  

NASA Technical Reports Server (NTRS)

The multidisciplinary concept of "bioinspired engineering of exploration systems" (BEES) is described, which is a guiding principle of the continuing effort to develop biomorphic explorers as reported in a number of articles in the past issues of NASA Tech Briefs. The intent of BEES is to distill from the principles found in successful nature-tested mechanisms of specific crucial functions that are hard to accomplish by conventional methods but that are accomplished rather deftly in nature by biological organisms. The intent is not just to mimic operational mechanisms found in a specific biological organism but to imbibe the salient principles from a variety of diverse bio-organisms for the desired crucial function. Thereby, we can build explorer systems that have specific capabilities endowed beyond nature, as they will possess a combination of the best nature-tested mechanisms for that particular function. The approach consists of selecting a crucial function, for example, flight or some selected aspects of flight, and develop an explorer that combines the principles of those specific attributes as seen in diverse flying species into one artificial entity. This will allow going beyond biology and achieving unprecedented capability and adaptability needed in encountering and exploring what is as yet unknown. A classification of biomorphic flyers into two main classes of surface and aerial explorers is illustrated in the figure, with examples of a variety of biological organisms that provide the inspiration in each respective subclass. Such biomorphic explorers may possess varied mobility modes: surface-roving, burrowing, hopping, hovering, or flying, to accomplish surface, subsurface, and aerial exploration. Preprogrammed for a specific function, they could serve as one-way communicating beacons, spread over the exploration site, autonomously looking for/at the targets of interest. In a hierarchical organization, these biomorphic explorers would report to the next level of exploration mode (say, a large conventional lander/rover) in the vicinity. A widespread and affordable exploration of new/hazardous sites at lower cost and risk would thus become possible by utilizing a faster aerial flyer to cover long ranges and deploying a variety of function- specific, smaller biomorphic explorers for distributed sensing and local sample acquisition. Several conceptual biomorphic missions for planetary and terrestrial exploration applications have been illustrated in "Surface-Launched Explorers for Reconnaissance/ Scouting" (NPO-20871), NASA Tech Briefs, Vol. 26, No. 4 (April, 2002), page 69 and "Bio-Inspired Engineering of Exploration Systems," Journal of Space Mission Architecture, Issue 2, Fall 2000, pages 49-79.

Thakoor, Sanita

2003-01-01

46

Cascade Helps JPL Explore the Solar System  

NASA Technical Reports Server (NTRS)

At Jet Propulsion Laboratory (JPL), we are involved with the unmanned exploration of the solar system. Unmanned probes observe the planet surfaces using radar and optical cameras to take a variety of measurements.

Burke, G. R.

1996-01-01

47

International solar system exploration - Opportunities and obstacles  

NASA Technical Reports Server (NTRS)

A review is conducted of the exploration of the solar system carried out with the aid of various types of spacecraft during the past two decades, taking into account also space missions planned for thy next few years. A wealth of information has been obtained regarding the planets and their satellites. However, there remain many important questions concerning the solar system, and a continuation of space exploration for the solution of these questions appears highly desirable, particularly when the comparatively little cost of these missions is taken into account. However, major fiscal limitations within the U.S. economy have led to pressure to postpone any new solar system exploration projects unless there can be major reductions in their cost. A special committee has been studying the options for future low-cost solar system exploration missions, giving attention also to some options for international implementation. Various aspects of joint space projects are examined.

Moore, J. W.; Parks, R. J.

1982-01-01

48

Water Recovery System Evolved for Exploration.  

National Technical Information Service (NTIS)

A new water recovery system designed towards fulfillment of NASA's Vision for Space Exploration is presented. This water recovery system is an evolution of the current state-of-the-art system. Through novel integration of proven technologies for air and w...

M. J. E. ORourke J. L. Perry D. L. Carter

2006-01-01

49

Exploring Systems of Equations using Graphing Calculators  

NSDL National Science Digital Library

This lesson plan introduces the concept of graphing a system of linear equations. Students will use graphing technology to explore the meaning of the solution of a linear system including solutions that correspond to intersecting lines, parallel lines, and coinciding lines. Students will also do graph linear systems by hand.

2012-12-18

50

A perception system for a planetary explorer  

NASA Technical Reports Server (NTRS)

To perform planetary exploration without human supervision, a complete autonomous robot must be able to model its environment and to locate itself while exploring its surroundings. For that purpose, the authors propose a modular perception system for an autonomous explorer. The perception system maintains a consistent internal representation of the observed terrain from multiple sensor views. The representation can be accessed from other modules through queries. The perception system is intended to be used by the Ambler, a six-legged vehicle being built at CMU. A partial implementation of the system using a range scanner is presented as well as experimental results on a testbed that includes the sensor, one computer-controlled leg, and obstacles on a sandy surface.

Hebert, M.; Krotkov, E.; Kanade, T.

1989-01-01

51

Solar System Exploration, 1995-2000  

NASA Technical Reports Server (NTRS)

Goals for planetary exploration during the next decade include: (1) determine how our solar system formed, and understand whether planetary systems are a common phenomenon through out the cosmos; (2) explore the diverse changes that planets have undergone throughout their history and that take place at present, including those that distinguish Earth as a planet; (3) understand how life might have formed on Earth, whether life began anywhere else in the solar system, and whether life (including intelligent beings) might be a common cosmic phenomenon; (4) discover and investigate natural phenomena that occur under conditions not realizable in laboratories; (5) discover and inventory resources in the solar system that could be used by human civilizations in the future; and (6) make the solar system a part of the human experience in the same way that Earth is, and hence lay the groundwork for human expansion into the solar system in the coming century. The plan for solar system exploration is motivated by these goals as well as the following principle: The solar system exploration program will conduct flight programs and supporting data analysis and scientific research commensurate with United States leadership in space exploration. These programs and research must be of the highest scientific merit, they must be responsive to public excitement regarding planetary exploration, and they must contribute to larger national goals in technology and education. The result will be new information, which is accessible to the public, creates new knowledge, and stimulates programs of education to increase the base of scientific knowledge in the general public.

Squyres, S.; Varsi, G.; Veverka, J.; Soderblom, L.; Black, D.; Stern, A.; Stetson, D.; Brown, R. A.; Niehoff, J.; Squibb, G.

1994-01-01

52

Modular, Intelligent Power Systems for Space Exploration  

NASA Technical Reports Server (NTRS)

NASA's new Space Exploration Initiative demands that vehicles, habitats, and rovers achieve unprecedented levels of reliability, safety, effectiveness, and affordability. Modular and intelligent electrical power systems are critical to achieving those goals. Modular electrical power systems naturally increase reliability and safety through built-in fault tolerance. These modular systems also enable standardization across a multitude of systems, thereby greatly increasing affordability of the programs. Various technologies being developed to support this new paradigm for space power systems will be presented. Examples include the use of digital control in power electronics to enable better performance and advanced modularity functions such as distributed, master-less control and series input power conversion. Also, digital control and robust communication enables new levels of power system control, stability, fault detection, and health management. Summary results from recent development efforts are presented along with expected future technology development needs required to support NASA's ambitious space exploration goals.

Button, Robert

2006-01-01

53

Future exploration of the outer solar system  

NASA Astrophysics Data System (ADS)

Missions to the frigid outer reaches of our solar system present significant technological challenges, but there remains a breathtaking scope for new and exciting discoveries. Leigh Fletcher reports on an RAS meeting that demonstrated a host of innovative ideas to explore the giant planets.

Fletcher, Leigh

2013-04-01

54

Memory exploration for low power, embedded systems  

Microsoft Academic Search

In embedded system design, the designer has to choose an on- chip memory configuration that is suitable for a specific application. To aid in this design choice, we present a memory exploration strategy based on three performance metrics, namely, cache size, the number of processor cycles and the energy consumption. We show how the performance is affected by cache parameters

Wen-Tsong Shiue; Chaitali Chakrabarti

1999-01-01

55

Exploring the solar system — A current overview —  

NASA Astrophysics Data System (ADS)

This paper examines the history of robotic exploration of the solar system from the initial flights to present day. Analysis demonstrates how flight rate and spacecraft mass have varied in the programs of the major space faring countries. The paper also demonstrates how the faster, better, cheaper approach has significantly increased scientific productivity and program resiliency to failures.

Huckins, Earle K.; Elachi, Charles; Woods, Dan V.

2000-07-01

56

Ground Mobility Systems for Planetary Exploration  

Microsoft Academic Search

This paper surveys past and current designs of surface mobility systems lor planetary exploration i robots developed at JPL\\/Canech. Wheeled rovers are ! discussed in some detail, andxompared to new designs, such as legged and hopping robots, which are emerg- ing as viable alternatives to wheeled mobility for spe- cific applications. The paper discusses the main fea- tures of mobility

Paolo Fiorini

2000-01-01

57

Integrated Systems Health Management for Space Exploration  

NASA Technical Reports Server (NTRS)

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

Uckun, Serdar

2005-01-01

58

Boeing Integrated Defense System : Space Exploration  

NSDL National Science Digital Library

Space Exploration, a division of Boeing Integrated Defense Systems, is a leading global supplier of reusable and human space systems and services. Headquartered in Houston, the organization comprises more than 4,000 people operating in five locations. The organization s legacy began in the late 1950s with the X-15, spanned to the Apollo missions of the 1960 and 70s, and continues today with the Space Shuttle and International Space Station.

2007-12-12

59

The Solar System: Recent Exploration Results  

NASA Technical Reports Server (NTRS)

The solar system has been visited by space probes, ranging from the Mariner Mercury-Venus mission exploring inward toward the sun, and continuing through the Voyager probes out into interstellar space and (on its way now) the New Horizons probe to Pluto and the Kuiper belt. This talk examines what we know of the planets of the solar system from probes, and talks about where we will go from here.

Landis, Geoffrey A.

2006-01-01

60

The Small Explorer power system electronics  

NASA Technical Reports Server (NTRS)

The power system electronics for the NASA Goddard Space Flight Center Small Explorer Satellites are intended to satisfy various planned missions. The selected topology is a direct energy transfer (DET) system with the battery connected directly to the bus. The shunt control technique is a linear sequential full shunt which provides a simple solar array interface and can support both 3 axis stabilized and spinner satellites. In addition, it can meet stringent electromagnetic interference requirements which are expected on some Small Explorer Missions. The Power Systems Electronics (PSE) performs battery charge control using both temperature compensated charge/discharge ratio ampere hour integration and voltage-temperature control. The PSE includes all the circuits needed to perform telemetry and command functions using an optical MIL-STD-1773 interface.

Dakermanji, G.; Carlsson, U.; Temkin, D.; Culver, H.; Rodriguez, G. E.; Ahmad, A.

1991-01-01

61

Micro and Nano Systems for Space Exploration  

NASA Technical Reports Server (NTRS)

This slide presentation reviews the use of micro and nano systems in Space exploration. Included are: an explanation of the rationales behind nano and micro technologies for space exploration, a review of how the devices are fabricated, including details on lithography with more information on Electron Beam (E-Beam) lithography, and X-ray lithography, a review of micro gyroscopes and inchworm Microactuator as examples of the use of MicroElectoMechanical (MEMS) technology. Also included is information on Carbon Nanotubes, including a review of the CVD growth process. These micro-nano systems have given rise to the next generation of miniature X-ray Diffraction, X-ray Fluorescence instruments, mass spectrometers, and terahertz frequency vacuum tube oscillators and amplifiers, scanning electron microscopes and energy dispersive x-ray spectroscope. The nanotechnology has also given rise to coating technology, such as silicon nanotip anti-reflection coating.

Manohara, Harish

2007-01-01

62

On the alignment between the circumstellar disks and orbital planes of Herbig Ae/Be binary systems  

NASA Astrophysics Data System (ADS)

Context. The majority of the intermediate mass, pre-main-sequence Herbig Ae/Be stars reside in binary systems. As these systems are young, their properties may contain an imprint of the star formation process at intermediate masses (2-15 M?). However, these systems are generally spatially unresolved, making it difficult to probe their circumstellar environment to search for manifestations of their formation process, such as accretion disks. Aims: Here we investigate the formation mechanism of Herbig Ae/Be (HAe/Be) binary systems by studying the relative orientation of their binary orbits and circumstellar disks. Methods: We present linear spectropolarimetric observations of HAe/Be stars over the H? line, which are used to determine the orientation of their circumstellar disks. In conjunction with data from the literature, we obtain a sample of 20 binaries with known disk position angles (PAs). We subsequently compare our disk PA data to a model to investigate whether HAe/Be binary systems and their disks are co-planar. Moreover, in the light of a relatively recent suggestion that some HAe/Be star spectropolarimetric signatures may not necessarily be related to circumstellar disks, we re-assess the relationship between spectropolarimetric signatures and disk PAs. We do this by comparing spectropolarimetric and high spatial resolution observations of young stellar objects (both HAe/Be and T Tauri stars). Results: We find that spectropolarimetric observations of pre-main-sequence stars do indeed trace circumstellar disks. This finding is significant above the 3? level. In addition, our data are entirely consistent with the situation in which HAe/Be binary systems and circumstellar disks are co-planar, while random orientations can be rejected at the 2.2? level. Conclusions: The conclusive alignment (at more than 3?) between the disk PAs derived from linear spectropolarimetry and high spatial resolution observations indicates that linear spectropolarimetry traces disks. This in turn allows us to conclude that the orbital planes of HAe/Be binary systems and the disks around the primaries are likely to be co-planar, which is consistent with the notion that these systems form via monolithic collapse and subsequent disk fragmentation.

Wheelwright, H. E.; Vink, J. S.; Oudmaijer, R. D.; Drew, J. E.

2011-08-01

63

Performance Evaluation of Automatic Extraction System. Volume V. Geotechnical Investigations of the Roof Conditions in the Area Mined by the AES Machine. Final Technical Report.  

National Technical Information Service (NTIS)

This report presents the results of an in-depth geotechnical investigation aimed at assessing the roof, floor, and coal pillar conditions in the area mined by an experimental Automatic Extraction System (AES), built by National Mine Service Co. The study ...

D. A. Newman F. Rafia Z. T. Bieniawski

1980-01-01

64

Exploration Medical System Demonstration (EMSD) Project  

NASA Technical Reports Server (NTRS)

The Exploration Medical System Demonstration (EMSD) is a project under the Exploration Medical Capability (ExMC) element managed by the Human Research Program (HRP). The vision for the EMSD is to utilize ISS as a test bed to show that several medical technologies needed for an exploration mission and medical informatics tools for managing evidence and decision making can be integrated into a single system and used by the on-orbit crew in an efficient and meaningful manner. Objectives: a) Reduce and even possibly eliminate the time required for on-orbit crew and ground personnel (which include Surgeon, Biomedical Engineer (BME) Flight Controller, and Medical Operations Data Specialist) to access and move medical data from one application to another. b) Demonstrate that the on-orbit crew has the ability to access medical data/information using an intuitive and crew-friendly software solution to assist/aid in the treatment of a medical condition. c) Develop a common data management framework and architecture that can be ubiquitously used to automate repetitive data collection, management, and communications tasks for all crew health and life sciences activities.

Chin, Duane

2012-01-01

65

Exploration missions with a solar bimodal system  

NASA Astrophysics Data System (ADS)

This paper reports the results of an examination of planetary missions performed using a solar bimodal power and propulsion system. The Air force Phillips Laboratory has initiated an Integrated Solar Upper Stage (ISUS) technology demonstration program intended to mature solar bimodal technology to flight demonstration. The ISUS development program has focused on decreasing the cost of placing military satellites in high Earth orbits. This is accomplished by providing high specific impulse thrust for orbital transfer of spacecraft launched from smaller and less expensive boosters. This paper, however, reviews the applications of the ISUS technology to NASA solar system exploration missions. Mission analysis is presented showing the capability of the ISUS to deliver payloads from LEO to orbit around the Moon, Mars, Jupiter and Saturn. Both direct and gravity assisted trajectories are included, as are mission plans including both staged and unstaged strategies for Earth escape. A minimum mass spacecraft system for solar system exploration is presented, and used as a baseline to develop estimates of potential science payload deliverable to each planetary destination of interest as a function of launch booster capability. Booster fairing packaging considerations are examined. Earth escape time using a variety of perigee-kick orbit transfer strategies is also calculated, as is the communication capability of the ISUS as a function of planetary destination. It is shown that the ISUS offers significant potential as a propulsion system supporting interplanetary exploration. In general, it is found that the optimal trajectories for maximum science return require staging the spacecraft off the ISUS shortly before escape from the Earth. Providing other supporting technologies are developed, such a strategy would also allow the ISUS to be returned to LEO for reuse after each mission.

Zubrin, Robert; Chew, Gilbert; Lowther, Scott

1997-01-01

66

Jet Propulsion Laboratory's Space Explorations Part 2: Solar System Exploration  

NASA Technical Reports Server (NTRS)

This slide presentation reviews what is currently known about the solar system and the objects that make up the solar system. Information about the individual planets, comets, asteroids and moons is reviewed.

Chau, Savio

2005-01-01

67

Solar System Exploration: Fast Lesson Finder  

NSDL National Science Digital Library

How does one get around the solar system? Well, that's a tricky question unless you have a lot of time on your hands, but it's certainly easy to learn about the solar system with these useful lessons provided courtesy of NASA. Their Solar System Exploration website includes hundreds of lessons designed for grades K-12, which visitors can navigate by using the helpful tab menus to look for specific types of materials. The tabs include Grade Level, Solar System Body, Mission, and Topic. Visitors looking for high school materials will do well to look at the Globe Visualization Student Activities, which include close examinations of the Earth hydrology, including aspects of air temperature, ozone, salinity, and so on. Additionally, visitors can use the Education section on the left-hand side of the site to learn about scientists' work in the "Through the Eyes of Scientists" features.

2012-11-26

68

Exploring Exploring  

NSDL National Science Digital Library

Learners will investigate, discuss, and determine why humans have always explored the world (and now space) around them. Students determine these reasons for exploration through a class discussion. In the first activity, students use the Internet to examine the characteristics of past explorers and why they conducted their exploration. The students then examine why current explorers - including the students themselves - want to explore other worlds in the Solar System. By the end of the lesson, the students can conclude that no matter what or when we explore - past, present, or future - the reasons for exploration are the same; the motivation for exploration is universal.

69

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

70

The Mars Exploration Rover Instrument Positioning System  

NASA Technical Reports Server (NTRS)

During Mars Exploration Rover (MER) surface operations, the scientific data gathered by the in situ instrument suite has been invaluable with respect to the discovery of a significant water history at Meridiani Planum and the hint of water processes at work in Gusev Crater. Specifically, the ability to perform precision manipulation from a mobile platform (i.e., mobile manipulation) has been a critical part of the successful operation of Spirit and Opportunity rovers. As such, this paper describes the MER Instrument Positioning System that allows the in situ instruments to operate and collect their important science data using a robust, dexterous robotic arm combined with visual target selection and autonomous software functions.

Baumgartner, Eric T.; Bonitz, Robert G.; Shiraishi, Lori R.; Melko, Joseph P.; Leger, P. Chris

2005-01-01

71

Microarray assays for solar system exploration  

NASA Astrophysics Data System (ADS)

The detection of evidence of extinct and extant life is a key issue in astrobiological research, particularly with respect to future exploration of the solar system. Simple life forms may have evolved and developed on planetary bodies such as Mars or Europa. At this point in time, tests whether life once was or still is present can only be carried out by means of in situ experiments. Here, we discuss the potential and advantages of immunological concepts for life detection and the development of a miniaturized automated immunoassay flight device.

Steele, Andrew; Toporski, Jan; McKay, David S.; Schweitzer, Mary; Pincus, Seth; Pérez-Mercader, Juan; Parro García, Victor

2001-08-01

72

Automated Operations Development for Advanced Exploration Systems  

NASA Technical Reports Server (NTRS)

Automated space operations command and control software development and its implementation must be an integral part of the vehicle design effort. The software design must encompass autonomous fault detection, isolation, recovery capabilities and also provide single button intelligent functions for the crew. Development, operations and safety approval experience with the Timeliner system on-board the International Space Station (ISS), which provided autonomous monitoring with response and single command functionality of payload systems, can be built upon for future automated operations as the ISS Payload effort was the first and only autonomous command and control system to be in continuous execution (6 years), 24 hours a day, 7 days a week within a crewed spacecraft environment. Utilizing proven capabilities from the ISS Higher Active Logic (HAL) System [1] , along with the execution component design from within the HAL 9000 Space Operating System [2] , this design paper will detail the initial HAL System software architecture and interfaces as applied to NASA s Habitat Demonstration Unit (HDU) in support of the Advanced Exploration Systems, Autonomous Mission Operations project. The development and implementation of integrated simulators within this development effort will also be detailed and is the first step in verifying the HAL 9000 Integrated Test-Bed Component [2] designs effectiveness. This design paper will conclude with a summary of the current development status and future development goals as it pertains to automated command and control for the HDU.

Haddock, Angie; Stetson, Howard K.

2012-01-01

73

Flash LIDAR Systems for Planetary Exploration  

NASA Astrophysics Data System (ADS)

Ball Aerospace offers a mature, highly capable 3D flash-imaging LIDAR system for planetary exploration. Multi mission applications include orbital, standoff and surface terrain mapping, long distance and rapid close-in ranging, descent and surface navigation and rendezvous and docking. Our flash LIDAR is an optical, time-of-flight, topographic imaging system, leveraging innovations in focal plane arrays, readout integrated circuit real time processing, and compact and efficient pulsed laser sources. Due to its modular design, it can be easily tailored to satisfy a wide range of mission requirements. Flash LIDAR offers several distinct advantages over traditional scanning systems. The entire scene within the sensor's field of view is imaged with a single laser flash. This directly produces an image with each pixel already correlated in time, making the sensor resistant to the relative motion of a target subject. Additionally, images may be produced at rates much faster than are possible with a scanning system. And because the system captures a new complete image with each flash, optical glint and clutter are easily filtered and discarded. This allows for imaging under any lighting condition and makes the system virtually insensitive to stray light. Finally, because there are no moving parts, our flash LIDAR system is highly reliable and has a long life expectancy. As an industry leader in laser active sensor system development, Ball Aerospace has been working for more than four years to mature flash LIDAR systems for space applications, and is now under contract to provide the Vision Navigation System for NASA's Orion spacecraft. Our system uses heritage optics and electronics from our star tracker products, and space qualified lasers similar to those used in our CALIPSO LIDAR, which has been in continuous operation since 2006, providing more than 1.3 billion laser pulses to date.

Dissly, Richard; Weinberg, J.; Weimer, C.; Craig, R.; Earhart, P.; Miller, K.

2009-01-01

74

Space Launch System for Exploration and Science  

NASA Astrophysics Data System (ADS)

Introduction: The Space Launch System (SLS) is the most powerful rocket ever built and provides a critical heavy-lift launch capability enabling diverse deep space missions. The exploration class vehicle launches larger payloads farther in our solar system and faster than ever before. The vehicle's 5 m to 10 m fairing allows utilization of existing systems which reduces development risks, size limitations and cost. SLS lift capacity and superior performance shortens mission travel time. Enhanced capabilities enable a myriad of missions including human exploration, planetary science, astrophysics, heliophysics, planetary defense and commercial space exploration endeavors. Human Exploration: SLS is the first heavy-lift launch vehicle capable of transporting crews beyond low Earth orbit in over four decades. Its design maximizes use of common elements and heritage hardware to provide a low-risk, affordable system that meets Orion mission requirements. SLS provides a safe and sustainable deep space pathway to Mars in support of NASA's human spaceflight mission objectives. The SLS enables the launch of large gateway elements beyond the moon. Leveraging a low-energy transfer that reduces required propellant mass, components are then brought back to a desired cislunar destination. SLS provides a significant mass margin that can be used for additional consumables or a secondary payloads. SLS lowers risks for the Asteroid Retrieval Mission by reducing mission time and improving mass margin. SLS lift capacity allows for additional propellant enabling a shorter return or the delivery of a secondary payload, such as gateway component to cislunar space. SLS enables human return to the moon. The intermediate SLS capability allows both crew and cargo to fly to translunar orbit at the same time which will simplify mission design and reduce launch costs. Science Missions: A single SLS launch to Mars will enable sample collection at multiple, geographically dispersed locations and a low-risk, direct return of Martian material. For the Europa Clipper mission the SLS eliminates Venus and Earth flybys, providing a direct launch to the Jovian system, arriving four years earlier than missions utilizing existing launch vehicles. This architecture allows increased mass for radiation shielding, expansion of the science payload and provides a model for other outer planet missions. SLS provides a direct launch to the Uranus system, reducing travel time by two years when compared to existing launch capabilities. SLS can launch the Advanced Technology Large-Aperture Space Telescope (ATLAST 16 m) to SEL2, providing researchers 10 times the resolution of the James Webb Space Telescope and up to 300 times the sensitivity of the Hubble Space Telescope. SLS is the only vehicle capable of deploying telescopes of this mass and size in a single launch. It simplifies mission design and reduces risks by eliminating the need for multiple launches and in-space assembly. SLS greatly shortens interstellar travel time, delivering the Interstellar Explorer to 200 AU in about 15 years with a maximum speed of 63 km/sec--13.3 AU per year (Neptune orbits the sun at an approximate distance of 30 AU ).

Klaus, K.

2013-12-01

75

A Water Recovery System Evolved for Exploration  

NASA Technical Reports Server (NTRS)

A new water recovery system designed towards fulfillment of NASA's Vision for Space Exploration is presented. This water recovery system is an evolution of the current state-of-the-art system. Through novel integration of proven technologies for air and water purification, this system promises to elevate existing technology to higher levels of optimization. The novel aspect of the system is twofold: Volatile organic contaminants will be removed from the cabin air via catalytic oxidation in the vapor phase, prior to their absorption into the aqueous phase, and vapor compression distillation technology will be used to process the condensate and hygiene waste streams in addition to the urine waste stream. Oxidation kinetics dictate that removal of volatile organic contaminants from the vapor phase is more efficient. Treatment of the various waste streams by VCD will reduce the load on the expendable ion exchange and adsorption media which follow, and on the aqueous-phase volatile removal assembly further downstream. Incorporating these advantages will reduce the weight, volume, and power requirements of the system, as well as resupply.

ORourke, Mary Jane E.; Perry, Jay L.; Carter, Donald L.

2006-01-01

76

Exploring the Planets: Our Solar System  

NSDL National Science Digital Library

This resource offers information that will allow students to see just how big each planet and its major satellites are relative to each other in the scale model of the Solar System. Students will see where the planets are in relation to the Sun and to each other and learn just how big the Sun is compared to all the planets in our Solar System. Sections at this site include Planetary Physical Data, Planetary Satellites Physical Data, Relative Sizes of the Planets, Relative Planetary Distances from the Sun, and the Size of the Sun. In addition, each planet has an individual online section that gives an overview of what has been learned through imagery and data obtained from Earth-based and spacecraft exploration.

77

Small Scale Variants of the AES  

Microsoft Academic Search

In this paper we deflne small scale variants of the AES. These variants inherit the design features of the AES and provide a suitable framework for comparing difierent cryptanalytic methods. In particular, we provide some preliminary results and insights when using ofi-the- shelf computational algebra techniques to solve the systems of equations arising from these small scale variants.

Carlos Cid; Sean Murphy; Matthew J. B. Robshaw

2005-01-01

78

Exploring the Trans-Neptunian Solar System  

NASA Astrophysics Data System (ADS)

A profound question for scientists, philosophers and, indeed, all humans concerns how the solar system originated and subsequently evolved. To understand the solar system's formation, it is necessary to document fully the chemical and physical makeup of its components today, particularly those parts thought to retain clues about primordial conditions and processes.] In the past decade, our knowledge of the outermost, or trans-neptunian, region of the solar system has been transformed as a result of Earth-based observations of the Pluto-Charon system, Voyager 2's encounter with Neptune and its satellite Triton, and recent discoveries of dozens of bodies near to or beyond the orbit of Neptune. As a class, these newly detected objects, along with Pluto, Charon, and Triton, occupy the inner region of a hitherto unexplored component of the solar system, the Kuiper Belt. The Kuiper Belt is believed to be a reservoir of primordial objects of the type that formed in the solar nebula and eventually accreted to form the major planets. The Kuiper Belt is also thought to be the source of short-period comets and a population of icy bodies, the Centaurs, with orbits among the giant planets. Additional components of the distant outer solar system, such as dust and the Oort comet cloud, as well as the planet Neptune itself, are not discussed in this report. Our increasing knowledge of the trans-neptunian solar system has been matched by a corresponding increase in our capabilities for remote and in situ observation of these distant regions. Over the next 10 to 15 years, a new generation of ground- and space-based instruments, including the Keck and Gemini telescopes and the Space Infrared Telescope Facility, will greatly expand our ability to search for and conduct physical and chemical studies on these distant bodies. Over the same time span, a new generation of lightweight spacecraft should become available and enable the first missions designed specifically to explore the icy bodies that orbit 30 astronomical units (AU) or more from the Sun. The combination of new knowledge, plus the technological capability to greatly expand this knowledge over the next decade or so, makes this a particularly opportune time to review current understanding of the trans-neptunian solar system and to begin planning for the future exploration of this distant realm. Based on current knowledge, studies of trans-neptunian objects are important for a variety of reasons that can be summarized under five themes: (1) Exploration of new territory; (2) reservoirs of primitive materials; (3) Processes that reveal the solar system's origin and evolution; (4) Links to extrasolar planets; and (5) prebiotic chemistry. These five themes are not on an equal footing. The first three are well-established areas of scientific investigation and are backed up by a substantial body of observational and theoretical understanding. The last two, however are more speculative. They are included here because they raise a number of interesting possibilities that seem particularly suited to an interdisciplinary approach uniting planetary scientists with their colleagues in the astrophysical and life science communities. Although not considered in any detail in this report, the distant outer solar system also has direct relevance to Earth and the other terrestrial planets because it is the source of comets that bring volatiles into the inner solar system. The resulting inevitable impacts between comets and other planetary bodies can play major roles in the evolution of life as suggested by, for example, the Cretaceous-tertiary boundary bolide and the extinction of the dinosaurs.

1998-01-01

79

Logistics Modeling for Lunar Exploration Systems  

NASA Technical Reports Server (NTRS)

The extensive logistics required to support extended crewed operations in space make effective modeling of logistics requirements and deployment critical to predicting the behavior of human lunar exploration systems. This paper discusses the software that has been developed as part of the Campaign Manifest Analysis Tool in support of strategic analysis activities under the Constellation Architecture Team - Lunar. The described logistics module enables definition of logistics requirements across multiple surface locations and allows for the transfer of logistics between those locations. A key feature of the module is the loading algorithm that is used to efficiently load logistics by type into carriers and then onto landers. Attention is given to the capabilities and limitations of this loading algorithm, particularly with regard to surface transfers. These capabilities are described within the context of the object-oriented software implementation, with details provided on the applicability of using this approach to model other human exploration scenarios. Some challenges of incorporating probabilistics into this type of logistics analysis model are discussed at a high level.

Andraschko, Mark R.; Merrill, R. Gabe; Earle, Kevin D.

2008-01-01

80

Biology-Inspired Explorers for Space Systems  

NASA Astrophysics Data System (ADS)

Building upon three innovative technologies, each of which received a NTR award from NASA, a specific explorer is described. This "robot" does away with conventional gears, levers, pulleys,.... And uses "Muscle Materials" instead; these shape-memory materials, formerly in the Nickel-Titanium family, but now in the much wider class of ElectroActivePolymers(EAP), have the ability to precisely respond to pre"programmed" shape changes upon application of an electrical input. Of course, the pre"programs" are at the molecular level, much like in biological systems. Another important feature is the distributed power. That is, the power use in the "limbs" is distributed, so that if one "limb" should fail, the others can still function. The robot has been built and demonstrated to the media (newspapers and television). The fundamental control aspects are currently being worked upon, and we expect to have a more complete mathematical description of its operation. Future plans, and specific applications for reliable planetary exploration will be outlined.

Ramohalli, Kumar; Lozano, Peter; Furfaro, Roberto

2002-01-01

81

Mineralogical basis for the interpretation of multi-element (ICP-AES), oxalic acid, and aqua regia partial digestions of stream sediments for reconnaissance exploration geochemistry  

USGS Publications Warehouse

We have applied partial digestion procedures, primarily oxalic acid and aqua regia leaches, to several regional geochemical reconnaissance studies carried out using Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) analytical methods. We have chosen to use these two acids because the oxalic acid primarily attacks those compounds formed during secondary geochemical processes, whereas aqua regia will digest the primary sulfide phases as well as secondary phases. Application of the partial digestion technique has proven superior to total digestion because the concentration of metals in hydromorphic compounds and the sulfides is enhanced relative to the metals bound in the unattacked silicate phases. The aqua regia digestion attacks and leaches metals from the mafic chain silicates and the phyllosilicates (coordination number of VI or more), yielding a characteristic geochemical signature, but does not leach appreciable metal from many other silicates. In order to interpret the results from these leach studies, we have initiated an investigation of a large suite of hand-picked mineral separates. The study includes analyses of about two hundred minerals representing the common rock-forming minerals as well as end-member compositions of various silicates, oxides, sulfides, carbonates, sulfates, and some vanadates, molybdates, tungstates, and phosphates. The objective of this study is to evaluate the effect of leaching by acids of particular lattice sites in specific mineral structures. ?? 1987.

Church, S. E.; Mosier, E. L.; Motooka, J. M.

1987-01-01

82

Spacecraft Radio Scintillation and Solar System Exploration  

NASA Technical Reports Server (NTRS)

When a wave propagates through a turbulent medium, scattering by the random refractive index inhomogeneities can lead to a wide variety of phenomena that have been the subject of extensive study. The observed scattering effects include amplitude or intensity scintillation, phase scintillation, angular broadening, and spectral broadening, among others. In this paper, I will refer to these scattering effects collectively as scintillation. Although the most familiar example is probably the twinkling of stars (light wave intensity scintillation by turbulence in the Earth's atmosphere), scintillation has been encountered and investigated in such diverse fields as ionospheric physics, oceanography, radio astronomy, and radio and optical communications. Ever since planetary spacecraft began exploring the solar system, scintillation has appeared during the propagation of spacecraft radio signals through planetary atmospheres, planetary ionospheres, and the solar wind. Early studies of these phenomena were motivated by the potential adverse effects on communications and navigation, and on experiments that use the radio link to conduct scientific investigations. Examples of the latter are radio occultation measurements (described below) of planetary atmospheres to deduce temperature profiles, and the search for gravitational waves. However,these concerns soon gave way to the emergence of spacecraft radio scintillation as a new scientific tool for exploring small-scale dynamics in planetary atmospheres and structure in the solar wind, complementing in situ and other remote sensing spacecraft measurements, as well as scintillation measurements using natural (celestial) radio sources. The purpose of this paper is to briefly describe and review the solar system spacecraft radio scintillation observations, to summarize the salient features of wave propagation analyses employed in interpreting them, to underscore the unique remote sensing capabilities and scientific relevance of the scintillation measurements, and to highlight some of the scientific results obtained to date. Special emphasis is placed on comparing the remote sensing features of planetary and terrestrial scintillation measurements, and on contrasting spacecraft and natural radio source scintillation measurements. I will first discuss planetary atmospheres and ionospheres, and then the solar wind.

Woo, Richard

1993-01-01

83

AES chemunex ADIAFOOD detection system for Listeria spp. environmental sample testing.  

PubMed

The ADIAFOOD Detection System for the detection of Listeria species from environmental surfaces is based on real-time PCR technology and allows rapid pathogen detection within 21 h. The strength of the ADIAFOOD technology resides in its ability to rapidly and accurately detect Listeria species present on surfaces, such as stainless steel, plastic, ceramic, and sealed concrete. The technology is easy to use and versatile. PMID:22649931

Plante, Daniel; Côté, Yvan P; Giovannetti, Louisiane

2012-01-01

84

Cross Cutting Structural Design for Exploration Systems  

NASA Technical Reports Server (NTRS)

The challenge of our new National Space Policy and NASA's Vision for Space Exploration (VSE) is keyed to the development of more effective space access and transportation systems. Optimizing in-space systems through innovative cross cutting structural designs that reduce mass, combine functional requirements and improve performance can significantly advance spacecraft designs to meet the ever growing demands of our new National Space Policy. Dependence on limited structural designs is no longer an option. We must create robust materials, forms, function and evolvable systems. We must advance national policy objectives in the design, development, test and operation of multi-billion dollar new generation crew capsules by enabling them to evolve in meeting the requirements of long duration missions to the moon and mars. This paper discusses several current issues and major design drivers for consideration in structural design of advanced spacecraft systems. Approaches to addressing these multifunctional requirements is presented as well as a discussion on utilizing Functional Analysis System Technique (FAST) in developing cross cutting structural designs for future spacecraft. It will be shown how easy it is to deploy such techniques in any conceptual architecture definition or ongoing preliminary design. As experts in merging mission, safety and life support requirements of the frail human existence into robust vehicle and habitat design, we will conquer the final frontier, harness new resources and develop life giving technologies for mankind through more innovative designs. The rocket equation tells us that a reduction in mass optimizes our propulsive results. Primary and secondary structural elements provide for the containment of gases, fluids and solids; translate and sustain loads/impacts; conduct/radiate thermal energy; shield from the harmful effects of radiation; provide for grounding/bonding of electrical power systems; compartmentalize operational functions; and provide physical interface with multiple systems. How can we redefine, combine, substitute, rearrange and otherwise modify our structural systems to reduce mass? New technologies will be needed to fill knowledge gaps and propagate new design methods. Such an integrated process is paramount in maintaining U.S. leadership and in executing our national policy goals. The cross cutting process can take many forms, but all forms will have a positive affect on the demanding design environment through initial radical thinking. The author will illustrate such cross cutting results achievable through a formal process called FAST. The FAST example will be used to show how a multifunctional structural system concept for long duration spacecraft might be generated.

Semmes, Edmund B.

2007-01-01

85

Experimental validation of the cooling loop for a passive system for removing heat from the AES2006 protective envelope design for the Leningradskaya nuclear power plant site  

Microsoft Academic Search

Equipping new-generation nuclear power plants with passive means for controlling unanticipated accidents is one of the most\\u000a promising directions for increasing safety, which is being implemented in the AES-2006 design for the site of the Leningradskaya\\u000a nuclear power plant. An urgent problem is to obtain experimental validation of the passive system for removing heat from the\\u000a protective envelope during unanticipated

A. M. Bakhmet’ev; M. A. Bol’shukhin; V. V. Vakhrushev; A. M. Khizbullin; O. V. Makarov; V. V. Bezlepkin; S. E. Semashko; I. M. Ivkov

2009-01-01

86

Exploring our outer solar system - The Giant Planet System Observers  

NASA Astrophysics Data System (ADS)

As space-faring peoples now work together to plan and implement future missions that robotically prepare for landing humans to explore the Moon, and later Mars, the time is right to develop evolutionary approaches for extending this next generation of exploration beyond Earth's terrestrial planet neighbors to the realm of the giant planets. And while initial fly-by missions have been hugely successful in providing exploratory surveys of what lies beyond Mars, we need to consider now what robotic precursor mission capabilities we need to emplace that prepare us properly, and comprehensively, for long-term robotic exploration, and eventual human habitation, beyond Mars to the outer reaches of our solar system. To develop practical strategies that can establish prioritized capabilities, and then develop a means for achieving those capabilities within realistic budget and technology considerations, and in reasonable timeframes, is our challenge. We suggest one component of such an approach to future outer planets exploration is a series of Giant Planets System Observer (GPSO) missions that provide for long- duration observations, monitoring, and relay functions to help advance our understanding of the outer planets and thereby enable a sound basis for planning their eventual exploration by humans. We envision these missions as being comparable to taking Hubble-class remote-sensing facilities, along with the space physics capabilities of long-lived geospace and heliospheric missions, to the giant planet systems and dedicating long observing lifetimes (HST, 16 yr.; Voyagers, 29 yr.) to the exhaustive study and characterization of those systems. GPSO missions could feature 20-yr+ extended mission lifetimes, direct inject trajectories to maximize useful lifetime on target, placement strategies that take advantage of natural environment shielding (e.g., Ganymede magnetic field) where possible, orbit designs having favorable planetary system viewing geometries, comprehensive broadband remote sensing capabilities, a complementary and redundant science instrument suite, fully autonomous operations, high bandwidth science data downlink, advanced solar power technologies (supplemented where necessary), functional interfaces that are compatible with future small fly-by missions, and fail-safe features for mission operations and planetary protection, 1 among other considerations. We describe in this paper one example of a GPSO-type mission our team has been formulating as a practical approach that addresses many of the most highly-rated future science exploration needs in the Jovian system, including the exploration of Europa, observation of Io and Ganymede, and characterization of the Jovian atmosphere. We call this mission concept the Ganymede Exploration Observer with Probes (GEOP), and describe its architecture, mission design, system features, science capabilities, key trades, and notional development plan for implementation within the next decade. 2

Cooper, J. F.; Sittler, E. C., Jr.; Sturner, S. J.; Pitman, J. T.

87

EXPLOREMAP: An Exploration System for Choropleth Maps  

Microsoft Academic Search

Software for interactive choropleth mapping typically focuses on design, with the assumption that the resulting map will be used like a traditional paper one. We believe that interactive graphics also should enable users to explore the database underlying a map. In this vein, we have developed software that will permit users to both design a map and explore the underlying

Stephen L. Egbert; Terry A. Slocum

1992-01-01

88

System Considerations for an Exploration Spacesuit Upper Torso Architecture  

Microsoft Academic Search

NASA's Exploration Architecture announced in September 2005, calls for development and flight of a Crew Exploration Vehicle (CEV) no later than 2014 and return to the moon by 2020 with a goal to reach and explore Mars. Intra-Vehicular Activity (IVA) suit systems will need to comfortably protect the crew during launch entry and abort scenarios. Extra-Vehicular Activity (EVA) suit systems

ILC Dover; J. Ferl; L. Hewes; D. Cadogan; D. Graziosi; K. Splawn

89

Discovery of potent BACE-1 inhibitors containing a new hydroxyethylene (HE) Scaffold: Exploration of P1? alkoxy residues and an aminoethylene (AE) central core  

Microsoft Academic Search

In a preceding study we have described the development of a new hydroxyethylene (HE) core motif displaying P1 aryloxymethyl and P1? methoxy substituents delivering potent BACE-1 inhibitors. In a continuation of this work we have now explored the SAR of the S1? pocket by introducing a set of P1? alkoxy groups and evaluated them as BACE-1 inhibitors. Previously the P1

Catarina Björklund; Hans Adolfsson; Katarina Jansson; Jimmy Lindberg; Lotta Vrang; Anders Hallberg; Åsa Rosenquist; Bertil Samuelsson

2010-01-01

90

Comparison of theory and in situ observations for electron and ion distributions in the near wake of the Explorer 31 and AE-C satellites  

NASA Technical Reports Server (NTRS)

Measurements of electron density, plasma potential, and mean ion mass from the Explorer 31 satellite, and measurements of ion current, plasma potential, and ion composition from the Atmosphere Explorer C satellite were used in a comparative study with Parker's theory regarding the charged particle distribution in the near wake of an ionospheric satellite (1976). It is shown that theory and experiment agree fairly well in the angle-of-attack range between 90 and 135 deg. In the maximum rarefaction zone (between 145 and 180 deg), however, the theoretical model overestimates the measured ion depletion by several orders of magnitude. A comparison between theory and the Explorer 31 electron measurements shows that the theory again overestimates the electron depletion. These discrepancies are mainly due to the use of a steady-state theory and a single ion equation (using a mean ion mass). Improved agreement between theory and experiment can be obtained by the use of the time-dependent Vlasov-Poisson equations with separate equations for the various ion species.

Samir, U.; Fontheim, E. G.

1981-01-01

91

NASA Advanced Explorations Systems: Concepts for Logistics to Living  

NASA Technical Reports Server (NTRS)

The NASA Advanced Exploration Systems (AES) Logistics Reduction and Repurposing (LRR) project strives to enable a largely mission-independent cradle-to-grave-to-cradle approach to minimize logistics contributions to total mission architecture mass. The goals are to engineer logistics materials, common crew consumables, and container configurations to meet the following five basic goals: 1. Minimize intrinsic logistics mass and improve ground logistics flexibility. 2. Allow logistics components to be directly repurposed for on-orbit non-logistics functions (e.g., crew cabin outfitting) thereby indirectly reducing mass/volume. 3. Compact and process logistics that have not been directly repurposed to generate useful on-orbit components and/or compounds (e.g., radiation shielding, propellant, other usable chemical constituents). 4. Enable long-term stable storage and disposal of logistics end products that cannot be reused or repurposed (e.g., compaction for volume reduction, odor control, and maintenance of crew cabin hygienic conditions). 5. Allow vehicles in different mission phases to share logistics resources. This paper addresses the work being done to meet the second goal, the direct repurposing of logistics components to meet other on-orbit needs, through a strategy termed Logistics to Living (L2L). L2L has several areas but can be defined as repurposing or converting logistical items (bags, containers, foam, components, etc.) into useful crew items or life support augmentation on-orbit after they have provided their primary logistics function. The intent is that by repurposing items, dedicated crew items do not have to be launched and overall launch mass is decreased. For non-LEO missions, the vehicle interior volume will be relatively fixed so L2L will enable this volume to be used more effectively through reuse and rearrangement of logistical components. Past work in the area of L2L has already conceptually developed several potential technologies [Howe, Howard 2010]. Several of the L2L concepts that have shown the most potential in the past are based on NASA cargo transfer bags (CTBs) or their equivalents which are currently used to transfer cargo to and from the ISS. A high percentage of all logistics supplies are packaging mass and for a 6-month mission a crew of four might need over 100 CTBs. These CTBs are used for on-orbit transfer and storage but eventually becomes waste after use since down mass is very limited. The work being done in L2L also considering innovative interior habitat construction that integrate the CTBs into the walls of future habitats. The direct integration could provide multiple functions: launch packaging, stowage, radiation protection, water processing, life support augmentation, as well as structure. Reuse of these CTBs would reduce the amount of waste generated and also significantly reduce future up mass requirements for exploration missions. Also discussed here is the L2L water wall , an innovative reuse of an unfolded CTB as a passive water treatment system utilizing forward osmosis. The bags have been modified to have an inner membrane liner that allows them to purify wastewater. They may also provide a structural water-wall element that can be used to provide radiation protection and as a structural divider. Integration of the components into vehicle/habitat architecture and consideration of operations concepts and human factors will be discussed. In the future these bags could be designed to treat wastewater, concentrated brines, and solid wastes, and to dewater solid wastes and produce a bio-stabilized construction element. This paper will describe the follow-on work done in design, fabrication and demonstrations of various L2L concepts, including advanced CTBs for reuse/repurposing, internal outfitting studies and the CTB-based forward osmosis water wall.

Shull, Sarah A.; Howe, A. Scott; Flynn, Michael T.; Howard, Robert

2012-01-01

92

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

93

The Space Launch System: NASA's Exploration Rocket  

NASA Technical Reports Server (NTRS)

Powerful, versatile, and capable vehicle for entirely new missions to deep space. Vital to NASA's exploration strategy and the Nation's space agenda. Safe, affordable, and sustainable. Engaging the U.S. aerospace workforce and infrastructure. Competitive opportunities for innovations that affordably upgrade performance. Successfully meeting milestones in preparation for Preliminary Design Review in 2013. On course for first flight in 2017.

Blackerby, Christopher; Cate, Hugh C., III

2013-01-01

94

The Mars Exploration Rover instrument positioning system  

Microsoft Academic Search

During Mars Exploration Rover (MER) surface operations, the scientific data gathered by the in situ instrument suite has been invaluable with respect to the discovery of a significant water history at Meridiani Planum and the hint of water processes at work in Gusev Crater. Specifically, the ability to perform precision manipulation from a mobile platform (i.e., mobile manipulation) has been

Eric T. Baumgartner; Robert G. Bonitz; Joseph P. Melko; Lori R. Shiraishi; P. Chris Leger

2005-01-01

95

External Resource: Solar System Exploration: People  

NSDL National Science Digital Library

It takes hundreds of people -- machinists, engineers, scientists and many others -- to get a spacecraft from the planning stages to its destination in outer space. The people in this gallery represent just a few of the folks who make space exploration ide

1900-01-01

96

Breaking AES Encryption Model  

NSDL National Science Digital Library

The Breaking the AES Cipher Model encrypts a plaintext message using AES encryption and attempts to break this encryption using a plaintext attack. The attacker (Eve) obtains both the plaintext and the cyphered text for a message between two people, Alice and Bob, and systematically encrypts the plaintext using the AES encryption function with all possible keys until the function's output matches the known cyphered text. Eve starts with a key, feeds the key and the plaintext into the encryption function, and checks whether the cyphered text is equal to the known value. If so, Eve has found the correct key. Otherwise, Eve systematically changes the key until she is successful. If the key is small or if Eve knows some of the key, the computational task may be manageable. This model displays the computation time using both a sequential and a parallel do-loop implementation of the plaintext attack. The model is designed to show how Java performs standard AES encryption and to test the speedup and sizeup of parallel computation using multi-core processors. The Breaking the AES Cipher Model was created using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the model's jar file will run the simulation if Java is installed.

Christian, Wolfgang

2012-02-18

97

Optimization of System Maturity and Equivalent System Mass for Exploration Systems Development Planning  

NASA Technical Reports Server (NTRS)

The Exploration Systems Mission Directorate of the National Aeronautics and Space Administration (NASA) is currently pursuing the development of the next generation of human spacecraft and exploration systems throughout the Constellation Program. This includes, among others, habitation technologies for supporting lunar and Mars exploration. The key to these systems is the Exploration Life Support (ELS) system that composes several technology development projects related to atmosphere revitalization, water recovery, waste management and habitation. The proper functioning of these technologies is meant to produce sufficient and balanced resources of water, air, and food to maintain a safe and comfortable environment for long-term human habitation and exploration of space.

Magnaye, Romulo; Tan, Weiping; Ramirez-Marquez, Jose; Sauser, Bruce

2010-01-01

98

Intelligent Systems: Shaping the Future of Aeronautics and Space Exploration  

NASA Technical Reports Server (NTRS)

Intelligent systems are nature-inspired, mathematically sound, computationally intensive problem solving tools and methodologies that have become important for NASA's future roles in Aeronautics and Space Exploration. Intelligent systems will enable safe, cost and mission-effective approaches to air& control, system design, spacecraft autonomy, robotic space exploration and human exploration of Moon, Mars, and beyond. In this talk, we will discuss intelligent system technologies and expand on the role of intelligent systems in NASA's missions. We will also present several examples of which some are highlighted m this extended abstract.

Krishnakumar, Kalmanje; Lohn, Jason; Kaneshige, John

2004-01-01

99

Performance Assessment of the Exploration Water Recovery System.  

National Technical Information Service (NTIS)

A new water recovery system architecture designed to fulfill the National Aeronautics and Space Administration's (NASA) Space Exploration Policy has been tested at the Marshall Space Flight Center (MSFC). This water recovery system architecture evolved fr...

D. Tabb J. Perry

2008-01-01

100

Exploring Structure and Function in Biological Systems  

NSDL National Science Digital Library

In this media-rich lesson, students analyze structure and function relationships at different levels of organization in nonbiological systems and then perform a similar analysis using biological systems.

2007-08-09

101

Generic netlist representation for system and PE level design exploration  

Microsoft Academic Search

Designer productivity and design predictability are vital factors for successful embedded system design. Shrinking time-to-market and increasing complexity of these systems require more productive design approaches starting from high-level languages such as C. On the other hand, tight constraints of embedded systems require careful design exploration at system level (coarse grained exploration) and at the processing-element (PE) level (fine grained

Bita Gorjiara; Mehrdad Reshadi; Pramod Chandraiah; Daniel Gajski

2006-01-01

102

Enabling Solar System Exploration with Small Radioisotope Power Systems  

NASA Astrophysics Data System (ADS)

The increased use of smaller spacecraft over the last decade, in combination with studies of potential science applications, has suggested that a wide range of low power missions and applications could be enabled by a new generation of conceptual small radioisotope power systems with power levels in the range of 20 mW to a few 10's of watts. Such systems have the potential to extend the capability of small science payloads and instruments, and to enable applications such as long-lived meteorological/seismological stations broadly distributed across planetary surfaces, navigational beacons, small landers or rovers at extreme latitudes or in regions of low solar flux, surface and atmosphere-based mobility systems, subsurface probes, including autonomous boring devices, and deep space micro-spacecraft and sub-satellites. Such units could also find application in future human exploration missions involving use of monitoring stations and autonomous devices, similar to the ALSEP units deployed on the Moon during the Apollo program. We present descriptions and performance predictions of conceptual milliwatt and multi-watt class small RPS designs. Our team has performed a number of mission studies to evaluate the potential contributions of small RPS systems. Among these are a long-duration Europa lander; MER-class Lunar and Mars rovers; small seismic monitoring stations; and an adjunct satellite for performing deep space fields and particles measurements. Although flight-qualified small RPS units do not presently exist, their potential to support a broad range of exploration tasks has led NASA and the Department of Energy (DOE) to consider their development such that they might be available for missions by the early part of next decade.

Abelson, R. D.; Balint, T. S.; Noravian, H.; Randolph, J. E.; Satter, C.; Schmidt, G. R.; Shirley, J. H.

2005-12-01

103

Exploring Embedded-Systems Architectures with Artemis  

Microsoft Academic Search

Because embedded systems mostly target mass production and often run on batteries, they should be cheap to realize and power efficient. In addition, they require a high degree of programmability to provide real-time performance for multiple applications and standards. However, performance requirements as well as cost and power-consumption constraints demand that substantial parts of these systems be implemented in dedicated

Andy D. Pimentel; Louis O. Hertzberger; Paul Lieverse; Pieter Van Der Wolf; Ed F. Deprettere

2001-01-01

104

Exploration\\/exploitation in adaptive recommender systems  

Microsoft Academic Search

Interactive information systems are often designed on the basis of little knowledge about users goals and about the final content of the information base. In addition users vary widely in their interests. This makes it useful to give such systems the ability to dynamically adapt to its users. Here we focus on \\

Hagen ten S. H. G; Someren van M; V. Hollink

2003-01-01

105

Human System Drivers for Exploration Missions  

NASA Technical Reports Server (NTRS)

Evaluation of DRM4 in terms of the human system includes the ability to meet NASA standards, the inclusion of the human system in the design trade space, preparation for future missions and consideration of a robotic precursor mission. Ensuring both the safety and the performance capability of the human system depends upon satisfying NASA Space Flight Human System Standards.1 These standards in turn drive the development of program-specific requirements for Near-earth Object (NEO) missions. In evaluating DRM4 in terms of these human system standards, the currently existing risk models, technologies and biological countermeasures were used. A summary of this evaluation is provided below in a structure that supports a mission architecture planning activities. 1. Unacceptable Level of Risk The duration of the DRM4 mission leads to an unacceptable level of risk for two aspects of human system health: A. The permissible exposure limit for space flight radiation exposure (a human system standard) would be exceeded by DRM4. B. The risk of visual alterations and abnormally high intracranial pressure would be too high. 1

Kundrot, Craig E.; Steinberg, Susan; Charles, John B.

2010-01-01

106

Electrical system options for space exploration  

NASA Technical Reports Server (NTRS)

The need for a space power utility concept is discussed and the impact of this concept on the engineering of space power systems is examined. Experiences gained from Space Station Freedom and SEI systems studies are used to discuss the factors that may affect the choice of frequency standards on which to build such a space power utility. Emphasis is given to electrical power control, conditioning, and distribution subsystems.

Bercaw, Robert W.; Cull, Ronald C.

1991-01-01

107

Anarchy in AE Aquarii  

NASA Astrophysics Data System (ADS)

Interest in AE Aqr remains high, as evidenced by the lively discussion that took place during the workshop. In this contribution I briefly remark on the results I presented at the workshop, then address topics that were raised during the discussion. I attempt to preserve the spirit and flavor of that discussion.

Welsh, W. F.

108

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

109

National Aeronautics and Space Administration Exploration Systems Interim Strategy  

NASA Technical Reports Server (NTRS)

Contents include the following: 1. The Exploration Systems Mission Directorate within NASA. Enabling the Vision for Space Exploration. The Role of the Directorate. 2. Strategic Context and Approach. Corporate Focus. Focused, Prioritized Requirements. Spiral Transformation. Management Rigor. 3. Achieving Directorate Objectives. Strategy to Task Process. Capability Development. Research and Technology Development. 4. Beyond the Horizon. Appendices.

2004-01-01

110

IN-SITU EXPLORATION OF MARS USING ROVER SYSTEMS  

Microsoft Academic Search

This paper will describe a NASA\\/JPL rover system that has been focused on developing technologies required for the in-situ exploration of Mars. In particular, JPL has been developing a class of rovers that carry significant science payloads that address geological exploration and discovery along with the ability to acquire samples from soils and rocks. The aim of this work is

Eric T. Baumgartner

2000-01-01

111

In-situ exploration of Mars using rover systems  

NASA Technical Reports Server (NTRS)

This paper will describe a NASA/JPL rover system that has been focused on developing technologies required for the in-situ exploration of Mars. In particular, JPL has been developing a class of rovers that carrry significant payloads that address geological exploration and discovery along with the ability to acquire samples from soils and rocks.

Baumgartner, E. T.

2000-01-01

112

Participatory Exploration: The Role of the User Contribution System  

NASA Technical Reports Server (NTRS)

This viewgraph presentation explores how NASA can apply the global shift in demographics, the popularity of collaborative technology and the desire for participation to the future of space exploration. Included in this is a review of the evolution of work, the engagement gap, user contribution systems and a case study concerning the "digital astronaut".

Skytland, Nicholas G.

2009-01-01

113

External Resource: Solar System Exploration: Planets  

NSDL National Science Digital Library

Our galaxy - the Milky Way - is a spiral galaxy with arms extending from the center like a pinwheel. Our solar system is in the Orion arm of the Milky Way. Our Sun is one of about 100 billion stars in the Milky Way. And our galaxy is just one of roughly 1

1900-01-01

114

Combustion and Reacting Systems for Exploration  

NASA Technical Reports Server (NTRS)

Contents include the foloving: 1. Spacecraft Fire Prevention, Detection, and Suppression. 2. Advanced Life Support. Air/water revitalization, waste management. 3. In Situ Resource Utilization (ISRU). Fuel/consumables from regolith/atmosphere. 4. Extra vehicular Activity. Air revitalization, power systems (MEMS scale combustors). 5. In-situ Fabrication and Repair.Of these we have the lead responsibility in Fire Safety.

Urban, David L.

2004-01-01

115

Drilling systems for extraterrestrial subsurface exploration.  

PubMed

Drilling consists of 2 processes: breaking the formation with a bit and removing the drilled cuttings. In rotary drilling, rotational speed and weight on bit are used to control drilling, and the optimization of these parameters can markedly improve drilling performance. Although fluids are used for cuttings removal in terrestrial drilling, most planetary drilling systems conduct dry drilling with an auger. Chip removal via water-ice sublimation (when excavating water-ice-bound formations at pressure below the triple point of water) and pneumatic systems are also possible. Pneumatic systems use the gas or vaporization products of a high-density liquid brought from Earth, gas provided by an in situ compressor, or combustion products of a monopropellant. Drill bits can be divided into coring bits, which excavate an annular shaped hole, and full-faced bits. While cylindrical cores are generally superior as scientific samples, and coring drills have better performance characteristics, full-faced bits are simpler systems because the handling of a core requires a very complex robotic mechanism. The greatest constraints to extraterrestrial drilling are (1) the extreme environmental conditions, such as temperature, dust, and pressure; (2) the light-time communications delay, which necessitates highly autonomous systems; and (3) the mission and science constraints, such as mass and power budgets and the types of drilled samples needed for scientific analysis. A classification scheme based on drilling depth is proposed. Each of the 4 depth categories (surface drills, 1-meter class drills, 10-meter class drills, and deep drills) has distinct technological profiles and scientific ramifications. PMID:18598141

Zacny, K; Bar-Cohen, Y; Brennan, M; Briggs, G; Cooper, G; Davis, K; Dolgin, B; Glaser, D; Glass, B; Gorevan, S; Guerrero, J; McKay, C; Paulsen, G; Stanley, S; Stoker, C

2008-06-01

116

Formal System-level Design Space Exploration  

Microsoft Academic Search

The paper focuses on the formal aspects of the DIPLODOCUS environment. DIPLODOCUS is a UML profile intended for the modeling and verification of real-time and embedded applications meant to be executed on complex Systems-on-Chip. Application tasks and architectural elements (e.g., CPUs, bus, memories) are described with a UML-based language, using an open-source toolkit named TTool. Those descriptions may be automatically

Daniel Knorreck; Ludovic Apvrille; Renaud Pacalet

2010-01-01

117

Exploring the opioid system by gene knockout  

Microsoft Academic Search

The endogenous opioid system consists of three opioid peptide precursor genes encoding enkephalins (preproenkephalin, Penk), dynorphins (preprodynorphin, Pdyn) and ?-endorphin (?end), proopiomelanocortin (POMC) and three receptor genes encoding mu-opiod receptor (MOR), delta-opiod receptor (DOR) and kappa-opiod receptor (KOR). In the past years, all six genes have been inactivated in mice by homologous recombination. The analysis of spontaneous behavior in mutant

Brigitte L Kieffer; Claire Gavériaux-Ruff

2002-01-01

118

Exploring the perceptions of knowledge management systems  

Microsoft Academic Search

Purpose – Diffusion (spread in usage) of knowledge management systems (KMSs) depends on a number of factors. Among them perceptions of KMS, including perceived usefulness\\/benefits, perceived user-friendliness, perceived voluntary use and subject norms are significant factors. This paper aims to investigate the factors impacting the diffusion (spread and sustained use) of KMSs. Design\\/methodology\\/approach – This paper first presents an integrated

Jun Xu; Mohammed Quaddus

2005-01-01

119

Ares V: Application to Solar System Scientific Exploration  

NASA Technical Reports Server (NTRS)

The following sections describe Ares V performance and its payoff to a wide array of potential solar system exploration missions. Application to potential Astrophysics missions is addressed in Reference 3.

Reh, Kim; Spilker, Tom; Elliott, John; Balint, Tibor; Donahue, Ben; McCormick, Dave; Smith, David B.; Tandon, Sunil; Woodcock, Gordon

2008-01-01

120

The AE gene family of Cl/HCO3- exchangers.  

PubMed

Tubular acid-base transport regulates systemic acid-base balance. Transepithelial acid-base transport across nephron segments requires the coordinated control of intracellular pH and cellular volume by transporters of protons and bicarbonate. Bicarbonate transporter polypeptides are encoded by at least two gene families, SLC4 and SLC26. The SLC4 gene family includes at least three Na()+)-independent chloride-bicarbonate exchanger genes and multiple Na(+)-bicarbonate cotransporter and Na(+)-dependent anion exchanger genes. The most extensively studied among them are the Na(+)-independent anion exchangers, AE1, AE2, and AE3, all of which are expressed in kidney. The AE1 gene encodes eAE1 (band 3), the major intrinsic protein of the erythrocyte, as well as kAE1, the basolateral Cl/HCO3 exchanger of the acid-secreting Type A intercalated cell. Mutations in AE1 are responsible for some forms of heritable distal renal tubular acidosis. The widely expressed AE2 anion exchanger participates in recovery from alkaline load and in regulatory cell volume increase following shrinkage. AE2 can also be regulated by ammonium ion. These properties are not shared by the closely related AE1 anion exchanger. Less is known about AE3 in kidney. Structure-function studies of recombinant proteins involving chimeras, deletions, and point mutations have delineated regions of AE2 which are important in exhibition of the regulatory properties absent from AE1. These include regions of the transmembrane domain and the N-terminal cytoplasmic domain. Noncontiguous regions in the middle of the N-terminal cytoplasmic domain are of particular importance for acute regulation by several types of stimulus. PMID:12027221

Alper, Seth L; Darman, Rachel B; Chernova, Marina N; Dahl, Neera K

2002-01-01

121

Picking a Planet, Exploring Our Solar System  

NSDL National Science Digital Library

It is the year 2025 and a large company, Z-Tech, wants to put a hotel in space having it orbit around one of the planets in our solar system. Our 5th grade class has been given a very important job. We have to search for the perfect location for the hotel. Our job is to report back to the company with the planet that is the best place for an orbiting hotel. The Task: You are to write a report recommending which planet should be chosen. Your report should include pictures of the planet you recommended. Here are the questions you should answer in order to report back to Z-Tech with your recommendation. * Which planet will be the ...

Chari

2008-11-23

122

Exploring Merchant Adoption of Mobile Payment Systems: An Empirical Study  

Microsoft Academic Search

The growth of mobile commerce depends on widely accepted mobile payment systems. Although new mobile payment systems have been increasingly introduced in Asia, Europe and the United States, their adoption has remained modest. Little research has been conducted to examine and explain adopters’ views on the new payment technology. In this article, we explore merchant adoption of mobile payment systems

Niina Mallat; Virpi Kristiina Tuunainen

2008-01-01

123

AE aeronomy studies  

NASA Technical Reports Server (NTRS)

Chemical processes in the thermosphere and ionosphere using AE data were studied. These data were analyzed and interpreted in such a way as to verify and correct laboratory measured rate coefficients, obtain values for rate coefficients not measured in the laboratory, and to reveal and correct inadequacies in existing models of thermospheric chemistry. This activity stimulated new work in the laboratory measurement of rate coefficients by revealing errors in existing measurements and by suggesting new measurements that need to be made.

Walker, J. C. G.

1983-01-01

124

Plutonium well logging with the photoneutron uranium exploration system  

SciTech Connect

The Los Alamos National Laboratory prototype photoneutron uranium exploration system was recently demonstrated at the Hanford site near Richland, Washington, for Rockwell-Hanford Operations (Rockwell). The demonstration determined the field performance capabilities of the uranium exploration system for in situ, downhole measurements of transuranic waste concentrations. The uranium exploration system is indeed capable of detecting plutonium in the test wells at the waste sites investigated. The excellent signal-to-background ratio (15:1 in the worst case) of the system made positive plutonium determinations possible despite neutron backgrounds caused by spontaneous fission and (..cap alpha..,n) emitters. We present all the data collected from seven test wells and guidance for interpreting the data relative to the known uranium ore calibration of the system. The demonstration indicated no operational difficulties in the waste site environment, and routine use by Rockwell personnel appears practical.

Baker, M.P.; Marks, T.

1982-09-01

125

ADVANCED RADIOISOTOPE HEAT SOURCE AND PROPULSION SYSTEMS FOR PLANETARY EXPLORATION  

SciTech Connect

The exploration of planetary surfaces and atmospheres may be enhanced by increasing the range and mobility of a science platform. Fundamentally, power production and availability of resources are limiting factors that must be considered for all science and exploration missions. A novel power and propulsion system is considered and discussed with reference to a long-range Mars surface exploration mission with in-situ resource utilization. Significance to applications such as sample return missions is also considered. Key material selections for radioisotope encapsulation techniques are presented.

R. C. O'Brien; S. D. Howe; J. E. Werner

2010-09-01

126

Space Medicine Issues and Healthcare Systems for Space Exploration Medicine  

NASA Technical Reports Server (NTRS)

This viewgraph presentation reviews issues of health care in space. Some of the issues reviewed are: (1) Physiological adaptation to microgravity, partial gravity, (2) Medical events during spaceflight, (3) Space Vehicle and Environmental and Surface Health Risks, (4) Medical Concept of Operations (CONOPS), (4a) Current CONOPS & Medical Hardware for Shuttle (STS) and ISS, (4b) Planned Exploration Medical CONOPS & Hardware needs, (5) Exploration Plans for Lunar Return Mission & Mars, and (6) Developing Medical Support Systems.

Scheuring, Richard A.; Jones, Jeff

2007-01-01

127

Petrologic Constraints on Amorphous and Crystalline Magnesium Silicates: Dust Formation and Evolution in Selected Herbig Ae/Be Systems  

NASA Astrophysics Data System (ADS)

The Infrared Space Observatory, Spitzer Space Telescope, and Herschel Space Observatory surveys provided a wealth of data on the Mg-silicate minerals (forsterite, enstatite), silica, and "amorphous silicates with olivine and pyroxene stoichiometry" around Herbig Ae/Be stars. These incredible findings do not resonate with the mainstream Earth Sciences because of (1) disconnecting "astronomical nomenclature" and the long existing mineralogical and petrologic terminology of minerals and amorphous materials, and (2) the fact that Earth scientists (formerly geologists) are bound by the "Principle of Actualism" that was put forward by James Hutton (1726-1797). This principle takes a process-oriented approach to understanding mineral and rock formation and evolution. This paper will (1) review and summarize the results of laboratory-based vapor phase condensation and thermal annealing experiments, (2) present the pathways of magnesiosilica condensates to Mg-silicate mineral (forsterite, enstatite) formation and processing, and (3) present mineralogical and petrologic implications of the properties and compositions of the infrared-observed crystalline and amorphous dust for the state of circumstellar disk evolution. That is, the IR-observation of smectite layer silicates in HD142527 suggests the break-up of asteroid-like parent bodies that had experienced aqueous alteration. We discuss the persistence of amorphous dust around some young stars and an ultrafast amorphous to crystalline dust transition in HD 163296 that leads to forsterite grains with numerous silica inclusions. These dust evolution processes to form forsterite, enstatite ± tridymite could occur due to amorphous magnesiosilica dust precursors with a serpentine- or smectite-dehydroxylate composition.

Rietmeijer, Frans J. M.; Nuth, Joseph A.

2013-07-01

128

PETROLOGIC CONSTRAINTS ON AMORPHOUS AND CRYSTALLINE MAGNESIUM SILICATES: DUST FORMATION AND EVOLUTION IN SELECTED HERBIG Ae/Be SYSTEMS  

SciTech Connect

The Infrared Space Observatory, Spitzer Space Telescope, and Herschel Space Observatory surveys provided a wealth of data on the Mg-silicate minerals (forsterite, enstatite), silica, and ''amorphous silicates with olivine and pyroxene stoichiometry'' around Herbig Ae/Be stars. These incredible findings do not resonate with the mainstream Earth Sciences because of (1) disconnecting ''astronomical nomenclature'' and the long existing mineralogical and petrologic terminology of minerals and amorphous materials, and (2) the fact that Earth scientists (formerly geologists) are bound by the ''Principle of Actualism'' that was put forward by James Hutton (1726-1797). This principle takes a process-oriented approach to understanding mineral and rock formation and evolution. This paper will (1) review and summarize the results of laboratory-based vapor phase condensation and thermal annealing experiments, (2) present the pathways of magnesiosilica condensates to Mg-silicate mineral (forsterite, enstatite) formation and processing, and (3) present mineralogical and petrologic implications of the properties and compositions of the infrared-observed crystalline and amorphous dust for the state of circumstellar disk evolution. That is, the IR-observation of smectite layer silicates in HD142527 suggests the break-up of asteroid-like parent bodies that had experienced aqueous alteration. We discuss the persistence of amorphous dust around some young stars and an ultrafast amorphous to crystalline dust transition in HD 163296 that leads to forsterite grains with numerous silica inclusions. These dust evolution processes to form forsterite, enstatite {+-} tridymite could occur due to amorphous magnesiosilica dust precursors with a serpentine- or smectite-dehydroxylate composition.

Rietmeijer, Frans J. M. [Department of Earth and Planetary Sciences, MSC 03 2040, 1-University of New Mexico, Albuquerque, NM 87131-001 (United States); Nuth, Joseph A., E-mail: fransjmr@unm.edu [Astrochemistry Laboratory, Solar System Exploration Division, Code 691, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

2013-07-01

129

Hybrid Exploration Agent Platform and Sensor Web System  

NASA Technical Reports Server (NTRS)

A sensor web to collect the scientific data needed to further exploration is a major and efficient asset to any exploration effort. This is true not only for lunar and planetary environments, but also for interplanetary and liquid environments. Such a system would also have myriad direct commercial spin-off applications. The Hybrid Exploration Agent Platform and Sensor Web or HEAP-SW like the ANTS concept is a Sensor Web concept. The HEAP-SW is conceptually and practically a very different system. HEAP-SW is applicable to any environment and a huge range of exploration tasks. It is a very robust, low cost, high return, solution to a complex problem. All of the technology for initial development and implementation is currently available. The HEAP Sensor Web or HEAP-SW consists of three major parts, The Hybrid Exploration Agent Platforms or HEAP, the Sensor Web or SW and the immobile Data collection and Uplink units or DU. The HEAP-SW as a whole will refer to any group of mobile agents or robots where each robot is a mobile data collection unit that spends most of its time acting in concert with all other robots, DUs in the web, and the HEAP-SWs overall Command and Control (CC) system. Each DU and robot is, however, capable of acting independently. The three parts of the HEAP-SW system are discussed in this paper. The Goals of the HEAP-SW system are: 1) To maximize the amount of exploration enhancing science data collected; 2) To minimize data loss due to system malfunctions; 3) To minimize or, possibly, eliminate the risk of total system failure; 4) To minimize the size, weight, and power requirements of each HEAP robot; 5) To minimize HEAP-SW system costs. The rest of this paper discusses how these goals are attained.

Stoffel, A. William; VanSteenberg, Michael E.

2004-01-01

130

Multiple-Agent Air/Ground Autonomous Exploration Systems  

NASA Technical Reports Server (NTRS)

Autonomous systems of multiple-agent air/ground robotic units for exploration of the surfaces of remote planets are undergoing development. Modified versions of these systems could be used on Earth to perform tasks in environments dangerous or inaccessible to humans: examples of tasks could include scientific exploration of remote regions of Antarctica, removal of land mines, cleanup of hazardous chemicals, and military reconnaissance. A basic system according to this concept (see figure) would include a unit, suspended by a balloon or a blimp, that would be in radio communication with multiple robotic ground vehicles (rovers) equipped with video cameras and possibly other sensors for scientific exploration. The airborne unit would be free-floating, controlled by thrusters, or tethered either to one of the rovers or to a stationary object in or on the ground. Each rover would contain a semi-autonomous control system for maneuvering and would function under the supervision of a control system in the airborne unit. The rover maneuvering control system would utilize imagery from the onboard camera to navigate around obstacles. Avoidance of obstacles would also be aided by readout from an onboard (e.g., ultrasonic) sensor. Together, the rover and airborne control systems would constitute an overarching closed-loop control system to coordinate scientific exploration by the rovers.

Fink, Wolfgang; Chao, Tien-Hsin; Tarbell, Mark; Dohm, James M.

2007-01-01

131

The Exploration of Titan and the Saturnian System  

Microsoft Academic Search

The exploration of the outer solar system and in particular of the giant planets and their environments is an on-going process with the Cassini spacecraft currently around Saturn, the Juno mission to Jupiter preparing to depart and two large future space missions planned to launch in the 2020-2025 time frame for the Jupiter system and its satellites (Europa and Ganymede)

Athena Coustenis

2010-01-01

132

eID: A System for Exploration of Image Databases.  

ERIC Educational Resources Information Center

Describes an exploration system for large image databases. The system, which consists of three stages, allows user to interpret and annotate an image in the context in which that image appears, dramatically reducing the time taken to annotate a large collection of images. Includes 25 figures and two tables. (AEF)

Stan, Daniela; Sethi, Ishwar K.

2003-01-01

133

The CAPA Integrative Online System for College Major Exploration  

Microsoft Academic Search

Career assessment has advanced on several fronts, enabling a CAPA integrative online system for exploring college majors with unprecedented precision and utility. The key inventories in the system are the CAPA Confidence Inventory (CCI), with its 6 general and 27 specific scales, and the CAPA Interest Inventory, with its 6 general and 35 specific scales. Results for these inventories are

Nancy E. Betz; Fred H. Borgen

2010-01-01

134

A Methodology for Architecture Exploration of Heterogeneous Signal Processing Systems  

Microsoft Academic Search

We present a methodology for the exploration of signal processing architectures at the system level. The methodology, named Spade, provides a means to quickly build models of architectures at an abstract level, to easily map applications, modeled as Kahn Process Networks, onto these architecture models, and to analyze the performance of the resulting system by simulation. The methodology distinguishes between

Paul Lieverse; Pieter Van Der Wolf; Kees A. Vissers; Ed F. Deprettere

2001-01-01

135

The CAPA Integrative Online System for College Major Exploration  

ERIC Educational Resources Information Center

Career assessment has advanced on several fronts, enabling a CAPA integrative online system for exploring college majors with unprecedented precision and utility. The key inventories in the system are the CAPA Confidence Inventory (CCI), with its 6 general and 27 specific scales, and the CAPA Interest Inventory, with its 6 general and 35 specific…

Betz, Nancy E.; Borgen, Fred H.

2010-01-01

136

Scientific Assessment of NASA's Solar System Exploration Roadmap  

NASA Technical Reports Server (NTRS)

At its June 24-28, 1996, meeting, the Space Studies Board's Committee on Planetary and Lunar Exploration (COMPLEX), chaired by Ronald Greeley of Arizona State University, conducted an assessment of NASA's Mission to the Solar System Roadmap report. This assessment was made at the specific request of Dr. Jurgen Rahe, NASA's science program director for solar system exploration. The assessment includes consideration of the process by which the Roadmap was developed, comparison of the goals and objectives of the Roadmap with published National Research Council (NRC) recommendations, and suggestions for improving the Roadmap.

1996-01-01

137

Scientific Assessment of NASA's Solar System Exploration Roadmap  

NASA Astrophysics Data System (ADS)

At its June 24-28, 1996, meeting, the Space Studies Board's Committee on Planetary and Lunar Exploration (COMPLEX), chaired by Ronald Greeley of Arizona State University, conducted an assessment of NASA's Mission to the Solar System Roadmap report. This assessment was made at the specific request of Dr. Jurgen Rahe, NASA's science program director for solar system exploration. The assessment includes consideration of the process by which the Roadmap was developed, comparison of the goals and objectives of the Roadmap with published National Research Council (NRC) recommendations, and suggestions for improving the Roadmap.

1996-08-01

138

Modular antenna pointing system for the Explorer platform satellite  

NASA Technical Reports Server (NTRS)

A Modular Antenna Pointing System (MAPS) is described which was designed for on-orbit servicing and on-orbit exchange. The MAPS provides a data link between the Explorer Platform (EP) satellite and the Tracking and Data Relay Satellite (TDRS). The MAPS consists of a two axis gimbal set used fo position a High Gain Antenna (HGA) toward TDRS, system control electronics, and an extendable mast. The system was qualified and integrated with the EP satellite for an April 1992 launch.

Andrus, James; Korzeniowski, ED

1992-01-01

139

Matt Rogers on AES Energy Storage  

ScienceCinema

The Department of Energy and AES Energy Storage recently agreed to a $17.1M conditional loan guarantee commitment. This project will develop the first battery-based energy storage system to provide a more stable and efficient electrical grid for New York State's high-voltage transmission network. Matt Rogers is the Senior Advisor to the Secretary for Recovery Act Implementation.

Rogers, Matt

2013-05-29

140

Exploring \\  

Microsoft Academic Search

This paper builds upon existing research and commentary from a variety of disciplinary sources including Information Systems, Organisational and Management Studies, and the Social Sciences that focus upon the meaning, significance and impact of 'events' in both an organisational and a social sense. The aim of this paper is to define how the examination of the event is an appropriate,

Anita Greenhill; Gordon Fletcher

2007-01-01

141

Overview of NASA's Thermal Control System Development for Exploration Project  

NASA Technical Reports Server (NTRS)

NASA s Constellation Program includes the Orion, Altair, and Lunar Surface Systems project offices. The first two elements, Orion and Altair, are manned space vehicles while the third element is broader and includes several subelements including Rovers and a Lunar Habitat. The upcoming planned missions involving these systems and vehicles include several risks and design challenges. Due to the unique thermal environment, many of these risks and challenges are associated with the vehicles thermal control system. NASA s Exploration Systems Mission Directorate (ESMD) includes the Exploration Technology Development Program (ETDP). ETDP consists of several technology development projects. The project chartered with mitigating the aforementioned risks and design challenges is the Thermal Control System Development for Exploration Project. The risks and design challenges are addressed through a rigorous technology development process that culminates with an integrated thermal control system test. The resulting hardware typically has a Technology Readiness Level (TRL) of six. This paper summarizes the development efforts being performed by the technology development project. The development efforts involve heat acquisition and heat rejection hardware including radiators, heat exchangers, and evaporators. The project has also been developing advanced phase change material heat sinks and performing assessments for thermal control system fluids. The current paper will provide an update to a similar overview paper published at last year s International Conference on Environmental Systems (ICES).

Stephan, Ryan A.

2009-01-01

142

Nuclear power systems for Lunar and Mars exploration  

SciTech Connect

Initial studies of a variety of mission scenarios for the new Space Exploration Initiative, and the technologies necessary to enable or significantly enhance them, have identified the development of advanced space power systems - whether solar, chemical or nuclear - to be of prime importance. Lightweight, compact, reliable power systems for planetary rovers and a variety of surface vehicles, utility surface power, and power for advanced propulsion systems were identified as critical needs for these missions. This paper discusses these mission scenarios, the concomitant power system requirements; the power system options considered and identifies the significant potential benefits of nuclear power for meeting the power needs of the above applications.

Sovie, R.J.; Bozek, J.M.

1994-09-01

143

Nuclear power systems for lunar and Mars exploration  

NASA Technical Reports Server (NTRS)

Initial studies of a variety of mission scenarios for the new Space Exploration Initiative, and the technologies necessary to enable or significantly enhance them, have identified the development of advanced space power systems whether solar, chemical or nuclear to be of prime importance. Lightweight, compact, reliable power systems for planetary rovers and a variety of surface vehicles, utility surface power, and power for advanced propulsion systems have been identified as critical needs for these missions. These mission scenarios, the concomitant power system requirements, and power system options considered are discussed. The significant potential benefits of nuclear power are identified for meeting the power needs of the above applications.

Sovie, R. J.; Bozek, J. M.

1990-01-01

144

Radioisotope-based Nuclear Power Strategy for Exploration Systems Development  

SciTech Connect

Nuclear power will play an important role in future exploration efforts. Its benefits pertain to practically all the different timeframes associated with the Exploration Vision, from robotic investigation of potential lunar landing sites to long-duration crewed missions on the lunar surface. However, the implementation of nuclear technology must follow a logical progression in capability that meets but does not overwhelm the power requirements for the missions in each exploration timeframe. It is likely that the surface power infrastructure, particularly for early missions, will be distributed in nature. Thus, nuclear sources will have to operate in concert with other types of power and energy storage systems, and must mesh well with the power architectures envisioned for each mission phase. Most importantly, they must demonstrate a clear advantage over other non-nuclear options (e.g., solar power, fuel cells) for their particular function. This paper describes a strategy that does this in the form of three sequential system developments. It begins with use of radioisotope generators currently under development, and applies the power conversion technology developed for these units to the design of a simple, robust reactor power system. The products from these development efforts would eventually serve as the foundation for application of nuclear power systems for exploration of Mars and beyond.

Schmidt, George R.; Houts, Michael G. [NASA Marshall Space Flight Center, Huntsville, AL 35812 (United States)

2006-01-20

145

Information technology aided exploration of system design spaces  

NASA Technical Reports Server (NTRS)

We report on a practical application of information technology techniques to aid system engineers effectively explore large design spaces. We make use of heuristic search, visualization and data mining, the combination of which we have implemented wtihin a risk management tool in use at JPL and NASA.

Feather, Martin S.; Kiper, James D.; Kalafat, Selcuk

2004-01-01

146

Advanced thermionic systems for the Space Exploration Initiative  

Microsoft Academic Search

Technology assessments and system comparison study results are presented to support the candidacy of in-core thermionics for U.S. Space Exploration Initiative (SEI) applications. The history of thermionic development is reviewed, advanced technology options are identified, and the technology paths needed to reach readiness for the SEI goals are discussed.

Thomas H. van Hagan; Joseph C. Mills

1991-01-01

147

2004: the Old Continent explores the Solar System  

Microsoft Academic Search

This a fundamental year in the history of exploration of the Solar System. I will discuss the role that Europe has taken to undergo this enterprise. I will start from the recent results on Mars, due to Mars Express, indicating the presence of minerals, like Hematitis, that usually involve water in the process of formation. I will discuss the new

M. Fulchignoni

2004-01-01

148

Advanced thermionic systems for the Space Exploration Initiative  

NASA Astrophysics Data System (ADS)

Technology assessments and system comparison study results are presented to support the candidacy of in-core thermionics for U.S. Space Exploration Initiative (SEI) applications. The history of thermionic development is reviewed, advanced technology options are identified, and the technology paths needed to reach readiness for the SEI goals are discussed.

van Hagan, Thomas H.; Mills, Joseph C.

1991-09-01

149

Overview of NASA's Thermal Control System Development for Exploration Project  

NASA Technical Reports Server (NTRS)

NASA's Constellation Program includes the Orion, Altair, and Lunar Surface Systems project offices. The first two elements, Orion and Altair, are manned space vehicles while the third element is broader and includes several sub-elements including Rovers and a Lunar Habitat. The upcoming planned missions involving these systems and vehicles include several risks and design challenges. Due to the unique thermal environment, many of these risks and challenges are associated with the vehicles' thermal control system. NASA's Exploration Systems Mission Directorate (ESMD) includes the Exploration Technology Development Program (ETDP). ETDP consists of several technology development projects. The project chartered with mitigating the aforementioned risks and design challenges is the Thermal Control System Development for Exploration Project. The risks and design challenges are addressed through a rigorous technology development process that culminates with an integrated thermal control system test. The resulting hardware typically has a Technology Readiness Level (TRL) of six. This paper summarizes the development efforts being performed by the technology development project. The development efforts involve heat acquisition and heat rejection hardware including radiators, heat exchangers, and evaporators. The project has also been developing advanced phase change material heat sinks and performing assessments for thermal control system fluids.

Stephan, Ryan A.

2010-01-01

150

Overview of NASA's Thermal Control System Development for Exploration Project  

NASA Technical Reports Server (NTRS)

NASA's Constellation Program includes the Orion, Altair, and Lunar Surface Systems (LSS) project offices. The first two elements, Orion and Altair, are manned space vehicles while the third element is broader and includes several subelements including Rovers and a Lunar Habitat. The upcoming planned missions involving these systems and vehicles include several risks and design challenges. Due to the unique thermal environment, many of these risks and challenges are associated with the vehicles thermal control system. NASA s Exploration Systems Mission Directorate (ESMD) includes the Exploration Technology Development Program (ETDP). ETDP consists of several technology development projects. The project chartered with mitigating the aforementioned risks and design challenges is the Thermal Control System Development for Exploration Project. The risks and design challenges are addressed through a rigorous technology development process that culminates with an integrated thermal control system test. The resulting hardware typically has a Technology Readiness Level (TRL) of approximately six. This paper summarizes the development efforts being performed by the technology development project. The development efforts involve heat acquisition and heat rejection hardware including radiators, heat exchangers, and evaporators. The project has also been developing advanced phase change material heat sinks and performing assessments for thermal control system fluids.

Stephan, Ryan A.

2009-01-01

151

Lunar Dust Characterization for Exploration Life Support Systems  

NASA Technical Reports Server (NTRS)

Lunar dust effects can have a significant impact on the performance and maintenance of future exploration life support systems. Filtration systems will be challenged by the additional loading from lunar dust, and mitigation technology and strategies have to be adapted to protect sensitive equipment. An initial characterization of lunar dust and simulants was undertaken. The data emphasize the irregular morphology of the dust particles and the frequency dependence of lunar dust layer detachment from shaken surfaces.

Agui, Juan H.

2007-01-01

152

Mars Exploration Rover: thermal design is a system engineering activity  

NASA Technical Reports Server (NTRS)

The Mars Exploration Rovers (MER), were launched in June and July of 2003, repsectively and successfully landed on Mars in early and late January of 2004, repectively. The flight system architecture implemented many successful features of the Mars Pathfinder (MPF) system: A cruise stage that transported an entry vehicle that housed the Lander, which in turn, used airbags to cushion the Rover during the landing event.

Tsuyuki, Glenn T.; Avila, Arturo; Awaya, Henry I.; Krylo, Robert; Novak, Keith; Phillips, Charles

2003-01-01

153

A System for Multimodal Exploration of Social Spaces  

Microsoft Academic Search

This paper describes a system developed to help people explore local communities by providing navigation services in social\\u000a spaces created by members of the communities. Just as a community’s social space is formed by communication and knowledge-sharing\\u000a practices, the proposed system utilizes data of the corresponding social network to reconstruct the social space, which is\\u000a otherwise not physically perceptible but

Victor V. Kryssanov; Shizuka Kumokawa; Igor Goncharenko; Hitoshi Ogawa

2008-01-01

154

Human Centered Autonomous and Assistant Systems Testbed for Exploration Operations  

NASA Technical Reports Server (NTRS)

The Engineering and Mission Operations Directorates at NASA Johnson Space Center are combining laboratories and expertise to establish the Human Centered Autonomous and Assistant Systems Testbed for Exploration Operations. This is a testbed for human centered design, development and evaluation of intelligent autonomous and assistant systems that will be needed for human exploration and development of space. This project will improve human-centered analysis, design and evaluation methods for developing intelligent software. This software will support human-machine cognitive and collaborative activities in future interplanetary work environments where distributed computer and human agents cooperate. We are developing and evaluating prototype intelligent systems for distributed multi-agent mixed-initiative operations. The primary target domain is control of life support systems in a planetary base. Technical approaches will be evaluated for use during extended manned tests in the target domain, the Bioregenerative Advanced Life Support Systems Test Complex (BIO-Plex). A spinoff target domain is the International Space Station (ISS) Mission Control Center (MCC). Prodl}cts of this project include human-centered intelligent software technology, innovative human interface designs, and human-centered software development processes, methods and products. The testbed uses adjustable autonomy software and life support systems simulation models from the Adjustable Autonomy Testbed, to represent operations on the remote planet. Ground operations prototypes and concepts will be evaluated in the Exploration Planning and Operations Center (ExPOC) and Jupiter Facility.

Malin, Jane T.; Mount, Frances; Carreon, Patricia; Torney, Susan E.

2001-01-01

155

Power system requirements and selection for the space exploration initiative  

SciTech Connect

The Space Exploration Initiative (SEI) seeks to reestablish a US program of manned and unmanned space exploration. The President has called for a program which includes a space station element, a manned habitation of the moon, and a human exploration of Mars. The NASA Synthesis Group has developed four significantly different architectures for the SEI program. One key element of a space exploration effort is the power required to support the missions. The Power Speciality Team of the Synthesis Group was tasked with assessing and evaluating the power requirements and candidate power technologies for such missions. Inputs to the effort came from existing NASA studies as well as other governments agency inputs such as those from DOD and DOE. In addition, there were industry and university briefings and results of solicitations from the AIAA and the general public as part of the NASA outreach effort. Because of the variety of power needs in the SEI program, there will be a need for multiple power system technologies including solar, nuclear and electrochemical. Due to the high rocket masses required to propel payloads to the moon and beyond to Mars, there is great emphasis placed on the need for high power density and high energy density systems. Power system technology development work is needed results will determine the ultimate technology selections. 23 refs., 10 figs.

Biringer, K.L. (Sandia National Labs., Albuquerque, NM (United States)); Bartine, D.E. (Oak Ridge National Lab., TN (United States)); Buden, D. (Idaho National Engineering Lab., Idaho Falls, ID (United States)); Foreman, J. (Naval Research Lab., Washington, DC (United States)); Harrison, S. (Strategic Defense Initiative Organization, Washington, DC (United States))

1991-01-01

156

Project SPECTRA! Phase II: Developing Solar System Exploration Data Stories  

NASA Astrophysics Data System (ADS)

Project SPECTRA!, a program that combines math and science in an engineering framework, emphasizes hands-on and data-based activities for students in Grades 7 through 10. During the initial phase of Project SPECTRA!, we developed a series of foundational lessons that engaged students in the basics of light and spectroscopy, building spectroscopes at a variety of levels, and learning how to use light to give information about our solar system. During Phase II of the program, Project SPECTRA! is developing a wide range of Solar System Exploration Data Stories, where authentic data from NASA missions are brought into the classroom in a constrained and contextual way and work towards a specific space science teaching goal. Data stories explore a myriad of solar system bodies, looking at surface and atmospheric composition, atmospheric dynamics, planetary history and habitability.

Murphy, N.; Cobabe-Ammann, E.; Wood, E.

2007-12-01

157

Simulation Based Acquisition for NASA's Office of Exploration Systems  

NASA Technical Reports Server (NTRS)

In January 2004, President George W. Bush unveiled his vision for NASA to advance U.S. scientific, security, and economic interests through a robust space exploration program. This vision includes the goal to extend human presence across the solar system, starting with a human return to the Moon no later than 2020, in preparation for human exploration of Mars and other destinations. In response to this vision, NASA has created the Office of Exploration Systems (OExS) to develop the innovative technologies, knowledge, and infrastructures to explore and support decisions about human exploration destinations, including the development of a new Crew Exploration Vehicle (CEV). Within the OExS organization, NASA is implementing Simulation Based Acquisition (SBA), a robust Modeling & Simulation (M&S) environment integrated across all acquisition phases and programs/teams, to make the realization of the President s vision more certain. Executed properly, SBA will foster better informed, timelier, and more defensible decisions throughout the acquisition life cycle. By doing so, SBA will improve the quality of NASA systems and speed their development, at less cost and risk than would otherwise be the case. SBA is a comprehensive, Enterprise-wide endeavor that necessitates an evolved culture, a revised spiral acquisition process, and an infrastructure of advanced Information Technology (IT) capabilities. SBA encompasses all project phases (from requirements analysis and concept formulation through design, manufacture, training, and operations), professional disciplines, and activities that can benefit from employing SBA capabilities. SBA capabilities include: developing and assessing system concepts and designs; planning manufacturing, assembly, transport, and launch; training crews, maintainers, launch personnel, and controllers; planning and monitoring missions; responding to emergencies by evaluating effects and exploring solutions; and communicating across the OExS enterprise, within the Government, and with the general public. The SBA process features empowered collaborative teams (including industry partners) to integrate requirements, acquisition, training, operations, and sustainment. The SBA process also utilizes an increased reliance on and investment in M&S to reduce design risk. SBA originated as a joint Industry and Department of Defense (DoD) initiative to define and integrate an acquisition process that employs robust, collaborative use of M&S technology across acquisition phases and programs. The SBA process was successfully implemented in the Air Force s Joint Strike Fighter (JSF) Program.

Hale, Joe

2004-01-01

158

NASA plans for exploration of the Earth-Sun system  

NASA Astrophysics Data System (ADS)

NASA's Science Mission Directorate's Earth-Sun System Division (ESSD) uses the unique vantage point of space to understand and explore Earth and the Sun. The relationship between the Sun and the Earth is at the heart of a complex, dynamic system that researchers do not yet fully understand. The Earth-Sun system is comprised of diverse components that interact in complex ways, requiring unique capabilities for characterizing, understanding, and predicting change. Therefore, researchers need to understand the Sun, the heliosphere, and Earth's atmosphere, lithosphere, hydrosphere, cryosphere, and biosphere as a single connected system. At the center of the solar system is the Sun, a magnetically variable star. This variability has impacts on life and technology that are felt here on Earth and throughout the solar system. NASA is working to understand this planetary system because it is the only star-planet system researchers can investigate in detail. Using NASA's view from space to study the Earth-Sun system, researchers also can better predict critical changes to Earth and its space environment. NASA's ESSD has a critical role in implementing three major national directives: - Climate Change Research via Climate Change Science Program - Global Earth Observation System of Systems via the U.S. Group on Earth Observations (US GEO) - Vision for Space Exploration NASA Earth-Sun system science conducts and sponsors research, collects new observations from space, develops technologies and extends science and technology education to learners of all ages. NASA now has a system of spacecraft with the ability to characterize the current state of the Earth-Sun system. In the years ahead, NASA's fleet will evolve into constellations of smart satellites that can be reconfigured based on the changing needs of science and technology. From there we envision an intelligent and integrated observation network composed of sensors deployed in vantage points from the subsurface to deep space. Technical and programmatic details and status of representative Earth-Sun system missions will be presented.

Neeck, Steven P.; Gay, Charles J.

2005-10-01

159

Automatic Event Detection in Noisy Environment for Material Process Monitoring by Laser AE Method  

NASA Astrophysics Data System (ADS)

Laser acoustic emission (AE) method is a unique in-situ and non-contact nondestructive evaluation (NDE) method. It has a capability to detect signals generated from crack generation and propagation, friction and other physical phenomena in materials even in high temperature environment. However, laser AE system has lower signal-to-noise ratio compared to the conventional AE system using PZT sensors, so it is difficult to apply this method in noisy environment. A novel AE measurement system to detect events in such difficult environments was developed. This system could continuously record all AE waveforms and enable unrestricted post-analyses. Noise reduction filters in frequency domain coupling with a new AE event extraction using multiple threshold values showed a good potential for AE signal processing. This system was successfully applied for crack monitoring of plasma spray deposition process of ceramic coating.

Ito, K.; Kuriki, H.; Araki, H.; Kuroda, S.; Enoki, M.

2014-06-01

160

NASA's Space Launch System: An Enabling Capability for International Exploration  

NASA Technical Reports Server (NTRS)

As the program moves out of the formulation phase and into implementation, work is well underway on NASA's new Space Launch System, the world's most powerful launch vehicle, which will enable a new era of human exploration of deep space. As assembly and testing of the rocket is taking place at numerous sites around the United States, mission planners within NASA and at the agency's international partners continue to evaluate utilization opportunities for this ground-breaking capability. Developed with the goals of safety, affordability, and sustainability in mind, the SLS rocket will launch the Orion Multi-Purpose Crew Vehicle (MPCV), equipment, supplies, and major science missions for exploration and discovery. NASA is developing this new capability in an austere economic climate, a fact which has inspired the SLS team to find innovative solutions to the challenges of designing, developing, fielding, and operating the largest rocket in history, via a path that will deliver an initial 70 metric ton (t) capability in December 2017 and then continuing through an incremental evolutionary strategy to reach a full capability greater than 130 t. SLS will be enabling for the first missions of human exploration beyond low Earth in almost half a century, and from its first crewed flight will be able to carry humans farther into space than they have ever voyaged before. In planning for the future of exploration, the International Space Exploration Coordination Group, representing 12 of the world's space agencies, has created the Global Exploration Roadmap, which outlines paths toward a human landing on Mars, beginning with capability-demonstrating missions to the Moon or an asteroid. The Roadmap and corresponding NASA research outline the requirements for reference missions for these destinations. SLS will offer a robust way to transport international crews and the air, water, food, and equipment they would need for such missions.

Creech, Stephen D.; May, Todd A.; Robinson, Kimberly F.

2014-01-01

161

Behavior of zirconium in the Zr sbnd OW(100) system at high temperature, studied by ISS, AES and work-function measurements  

NASA Astrophysics Data System (ADS)

The behavior of zirconium atoms at the W(100) surface associated with oxygen adsorption at different sample temperatures has been studied by Auger electron spectroscopy (AES), ion scattering spectroscopy (ISS), and the relative change of the work function (??) measured by the onset of the secondary electron energy distribution. The results have revealed: (i) adsorption of zirconium onto the W(100) surface followed by the elevation of the sample temperature up to 1710 K in an oxygen partial pressure of ˜ 2.7 × 10 -4 induces complete diffusion of zirconium atoms into the W(100) substrate; (ii) further exposure of oxygen induces co-existence of oxygen and tungsten on the surface at 1710 K, resulting in a work function of ˜ 4.37eV; (iii) keeping the sample temperature at ˜ 1710K, simple evacuation of the system has resulted in surface segregation of zirconium atoms to the surface to form a zirconium atomic layer on the top-most surface, reducing the work function to ˜ 2.7eV. The results have revealed that this specific behavior of zirconium atoms at high temperature assures, with very good reproducibility, the highly stable performance and long service life of Zr sbnd OW(100)-emitters in practical use, even in a low vacuum of 10 -6 Pa.

Lee, S. C.; Irokawa, Y.; Inoue, M.; Shimizu, R.

1995-06-01

162

Intelligent Sensor Systems for Integrated System Health Management in Exploration Applications  

Microsoft Academic Search

Future exploration missions will require significantly improved Integrated System Health Management (ISHM) capabilities throughout the mission. Vehicle systems that require intense human intervention or monitoring take valuable crew time from other critical functions and over- all are impediments to realization of NASA's Exploration Vision. Therefore, ISHM and the sen- sor systems that enable ISHM, are necessary throughout the vehicle to

G. W. Hunter; L. G. Oberle; G. Baakalini; J. Perotti; T. Hong

163

Mars Exploration Rover Mission: Entry, Descent, and Landing System Validation  

NASA Technical Reports Server (NTRS)

System validation for a Mars entry, descent, and landing system is not simply a demonstration that the electrical system functions in the associated environments. The function of this system is its interaction with the atmospheric and surface environment. Thus, in addition to traditional test-bed, hardware-in-the-loop, testing, a validation program that confirms the environmental interaction is required. Unfortunately, it is not possible to conduct a meaningful end-to-end test of a Mars landing system on Earth. The validation plan must be constructed from an interconnected combination of simulation, analysis and test. For the Mars Exploration Rover mission, this combination of activities and the logic of how they combined to the system's validation was explicitly stated, reviewed, and tracked as part of the development plan.

Mitcheltree, Robert A.; Lee, Wayne; Steltzner, Adam; SanMartin, Alejanhdro

2004-01-01

164

Meeting with the SME to design multimedia exploration systems  

Microsoft Academic Search

Multimedia exploration programs have different purposes than task-oriented computer-based training (CBT) programs. The multimedia\\u000a learning process may be more important than its learning product, with the student accessing a rich base of information and\\u000a symbol systems in a more idiosyncratic manner. The amount and structure of information in an exploratory environment also\\u000a differs from task- or objectives-based programs. These process

Martin Tessmer

1998-01-01

165

The invention that opened the solar system to exploration  

Microsoft Academic Search

The invention of gravity-propelled interplanetary space travel (also known as ``gravity-assist trajectories'') in the early 1960s broke the high-energy barrier of classical space travel based on reaction propulsion, and made possible the exploration of the entire solar system with instrumented spacecraft. In this concept, a free-fall spacecraft is launched from a launch planet P1 to a nearby planet P2 such

Michael A. Minovitch

2010-01-01

166

The invention that opened the solar system to exploration  

Microsoft Academic Search

The invention of gravity-propelled interplanetary space travel (also known as “gravity-assist trajectories”) in the early 1960s broke the high-energy barrier of classical space travel based on reaction propulsion, and made possible the exploration of the entire solar system with instrumented spacecraft. In this concept, a free-fall spacecraft is launched from a launch planet P1 to a nearby planet P2 such

Michael A. Minovitch

2010-01-01

167

ERP System Implementation: An Oil and Gas Exploration Sector Perspective  

NASA Astrophysics Data System (ADS)

Enterprise Resource Planning (ERP) systems provide integration and optimization of various business processes which leads to improved planning and decision quality, smoother coordination between business units resulting in higher efficiency, and quicker response time to customer demands and inquiries. This paper reports challenges, opportunities and outcome of ERP implementation in Oil & Gas exploration sector. This study will facilitate in understanding transition, constraints and implementation of ERP in this sector and also provide guidelines from lessons learned in this regard.

Mishra, Alok; Mishra, Deepti

168

Framework for the Parametric System Modeling of Space Exploration Architectures  

NASA Technical Reports Server (NTRS)

This paper presents a methodology for performing architecture definition and assessment prior to, or during, program formulation that utilizes a centralized, integrated architecture modeling framework operated by a small, core team of general space architects. This framework, known as the Exploration Architecture Model for IN-space and Earth-to-orbit (EXAMINE), enables: 1) a significantly larger fraction of an architecture trade space to be assessed in a given study timeframe; and 2) the complex element-to-element and element-to-system relationships to be quantitatively explored earlier in the design process. Discussion of the methodology advantages and disadvantages with respect to the distributed study team approach typically used within NASA to perform architecture studies is presented along with an overview of EXAMINE s functional components and tools. An example Mars transportation system architecture model is used to demonstrate EXAMINE s capabilities in this paper. However, the framework is generally applicable for exploration architecture modeling with destinations to any celestial body in the solar system.

Komar, David R.; Hoffman, Jim; Olds, Aaron D.; Seal, Mike D., II

2008-01-01

169

Enabling Solar System Exploration with Small Radioisotope Power Systems  

Microsoft Academic Search

The increased use of smaller spacecraft over the last decade, in combination with studies of potential science applications, has suggested that a wide range of low power missions and applications could be enabled by a new generation of conceptual small radioisotope power systems with power levels in the range of 20 mW to a few 10's of watts. Such systems

R. D. Abelson; T. S. Balint; H. Noravian; J. E. Randolph; C. Satter; G. R. Schmidt; J. H. Shirley

2005-01-01

170

Alenia Spazio: Space Programs for Solar System Exploration .  

NASA Astrophysics Data System (ADS)

Alenia Spazio is the major Italian space industry and one of the largest in Europe, with 2,400 highly skilled employees and 16,000 square meters of clean rooms and laboratories for advanced technological research that are among the most modern and well-equipped in Europe. The company has wide experience in the design, development, assembly, integration, verification and testing of complete space systems: satellites for telecommunications and navigation, remote sensing, meteorology and scientific applications; manned systems and space infrastructures; launch, transport and re-entry systems, and control centres. Alenia Spazio has contributed to the construction of over 200 satellites and taken part in the most important national and international space programmes, from the International Space Station to the new European global navigation system Galileo. Focusing on Solar System exploration, in the last 10 years the Company took part, with different roles, to the major European and also NASA missions in the field: Rosetta, Mars Express, Cassini; will soon take part in Venus Express, and is planning the future with Bepi Colombo, Solar Orbiter, GAIA and Exomars. In this paper, as in the presentation, a very important Earth Observation mission is also presented: GOCE. All in all, the Earth is by all means part of the Solar system as well and we like to see it as a planet to be explored.

Ferri, A.

171

NASA Technology Area 07: Human Exploration Destination Systems Roadmap  

NASA Technical Reports Server (NTRS)

This paper gives an overview of the National Aeronautics and Space Administration (NASA) Office of Chief Technologist (OCT) led Space Technology Roadmap definition efforts. This paper will given an executive summary of the technology area 07 (TA07) Human Exploration Destination Systems (HEDS). These are draft roadmaps being reviewed and updated by the National Research Council. Deep-space human exploration missions will require many game changing technologies to enable safe missions, become more independent, and enable intelligent autonomous operations and take advantage of the local resources to become self-sufficient thereby meeting the goal of sustained human presence in space. Taking advantage of in-situ resources enhances and enables revolutionary robotic and human missions beyond the traditional mission architectures and launch vehicle capabilities. Mobility systems will include in-space flying, surface roving, and Extra-vehicular Activity/Extravehicular Robotics (EVA/EVR) mobility. These push missions will take advantage of sustainability and supportability technologies that will allow mission independence to conduct human mission operations either on or near the Earth, in deep space, in the vicinity of Mars, or on the Martian surface while opening up commercialization opportunities in low Earth orbit (LEO) for research, industrial development, academia, and entertainment space industries. The Human Exploration Destination Systems (HEDS) Technology Area (TA) 7 Team has been chartered by the Office of the Chief Technologist (OCT) to strategically roadmap technology investments that will enable sustained human exploration and support NASA s missions and goals for at least the next 25 years. HEDS technologies will enable a sustained human presence for exploring destinations such as remote sites on Earth and beyond including, but not limited to, LaGrange points, low Earth orbit (LEO), high Earth orbit (HEO), geosynchronous orbit (GEO), the Moon, near-Earth objects (NEOs), which > 95% are asteroidal bodies, Phobos, Deimos, Mars, and beyond. The HEDS technology roadmap will strategically guide NASA and other U.S. Government agency technology investments that will result in capabilities enabling human exploration missions to diverse destinations generating high returns on investments.

Kennedy, Kriss J.; Alexander, Leslie; Landis, Rob; Linne, Diane; Mclemore, Carole; Santiago-Maldonado, Edgardo; Brown, David L.

2011-01-01

172

New vision solar system exploration missions study: Analysis of the use of biomodal space nuclear power systems to support outer solar system exploration missions. Final report.  

National Technical Information Service (NTIS)

This report presents the results of an analysis of the capability of nuclear bimodal systems to perform outer solar system exploration missions. Missions of interest include orbiter missions to Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. An initial...

1995-01-01

173

Development of Exploration Methods for Engineered Geothermal Systems  

NASA Astrophysics Data System (ADS)

The principle objective of an exploration program is to identify exploration drilling targets that will advance a prospect towards development and full-scale production or relinquish interest in the prospect. Engineered Geothermal Systems (EGS) exploration key geoscience parameters are temperature, lithology, and stress state at an economically feasible target depth. Our project tests the hypothesis that our proposed exploration methodology will identify potential EGS drilling targets at Dixie Valley. Dixie Valley was chosen as the test calibration site because it is a highly characterized geothermal resource was a sufficiently large database in the public domain. U.S. Department of Energy Geothermal Technologies Program under the American Recovery and Reinvestment Act has awarded funding to AltaRock to develop exploration methods for EGS by integrating geophysical, geological, and geochemical data sets. New seismic, gravity, magnetotellurics (MT), and geochemical data will be collected and integrated into the model to improve model coverage and resolution. Other model inputs will include geology, fault-kinematics, fracture-characterization, and earthquake fault-plane solutions to provide information on stress state. Where appropriate, additional geochemical measurements will be made to model geo-thermal temperatures at depth. The resulting integrated data model will be used to predict the EGS parameters of interest (temperature, lithology and stress state) with greater certainty and a "higher degree of non-uniqueness” across the test area. We hypothesize that successful EGS drilling targets will be identifiable through integration of existing and new geoscience data coupled with geostatictical and Subject Matter Expertise. Both the existing and the existing plus new data will be integrated into separate data models on a 5x5km grid with 1 km depth slices. The results of each data model will be evaluated for the degree of improvement relative to the parameters of interest.

Iovenitti, J. L.; Tibuleac, I. M.; Hopkins, D.; Cladouhos, T.; Karlin, R. E.; Wannamaker, P. E.; Kennedy, B. M.; Blackwell, D. D.; Clyne, M.

2010-12-01

174

Enabling Exploration Through the International Docking System Standard  

NASA Technical Reports Server (NTRS)

Human exploration missions beyond low earth orbit will likely require international cooperation in order to leverage limited resources. International standards can help enable cooperative missions by providing well understood, predefined interfaces allowing compatibility between unique spacecraft and systems. The International Space Station (ISS) partnership has developed a publically available International Docking System Standard (IDSS) that provides a solution to one of these key interfaces by defining a common docking interface. The docking interface provides a way for even dissimilar spacecraft to dock for exchange of crew and cargo, as well as enabling the assembly of large space systems. This paper provides an overview of the key attributes of the IDSS, an overview of the NASA Docking System (NDS), and the plans for updating the ISS with IDSS compatible interfaces. The NDS provides a state of the art, low impact docking system that will initially be made available to commercial crew and cargo providers. The ISS will be used to demonstrate the operational utility of the IDSS interface as a foundational technology for cooperative exploration.

Hatfield, Caris A.

2011-01-01

175

Nuclear thermal propulsion transportation systems for lunar/Mars exploration  

NASA Technical Reports Server (NTRS)

Nuclear thermal propulsion technology development is underway at NASA and DoE for Space Exploration Initiative (SEI) missions to Mars, with initial near-earth flights to validate flight readiness. Several reactor concepts are being considered for these missions, and important selection criteria will be evaluated before final selection of a system. These criteria include: safety and reliability, technical risk, cost, and performance, in that order. Of the concepts evaluated to date, the Nuclear Engine for Rocket Vehicle Applications (NERVA) derivative (NDR) is the only concept that has demonstrated full power, life, and performance in actual reactor tests. Other concepts will require significant design work and must demonstrate proof-of-concept. Technical risk, and hence, development cost should therefore be lowest for the concept, and the NDR concept is currently being considered for the initial SEI missions. As lighter weight, higher performance systems are developed and validated, including appropriate safety and astronaut-rating requirements, they will be considered to support future SEI application. A space transportation system using a modular nuclear thermal rocket (NTR) system for lunar and Mars missions is expected to result in significant life cycle cost savings. Finally, several key issues remain for NTR's, including public acceptance and operational issues. Nonetheless, NTR's are believed to be the 'next generation' of space propulsion systems - the key to space exploration.

Clark, John S.; Borowski, Stanley K.; Mcilwain, Melvin C.; Pellaccio, Dennis G.

1992-01-01

176

Overview of NASA's Thermal Control System Development for Exploration Project  

NASA Technical Reports Server (NTRS)

The now-cancelled Constellation Program included the Orion, Altair, and Lunar Surface Systems project offices. The first two elements, Orion and Altair, were planned to be manned space vehicles while the third element was much more diverse and included several sub-elements. Among other things, these sub-elements were Rovers and a Lunar Habitat. The planned missions involving these systems and vehicles included several risks and design challenges. Due to the unique thermal operating environment, many of these risks and challenges were associated with the vehicles thermal control system. NASA s Exploration Technology Development Program (ETDP) consisted of various technology development projects. The project chartered with mitigating the aforementioned thermal risks and design challenges was the Thermal Control System Development for Exploration Project. These risks and design challenges were being addressed through a rigorous technology development process that was planned to culminate with an integrated thermal control system test. Although the technologies being developed were originally aimed towards mitigating specific Constellation risks, the technology development process is being continued within a new program. This continued effort is justified by the fact that many of the technologies are generically applicable to future spacecraft thermal control systems. The current paper summarizes the development efforts being performed by the technology development project. The development efforts involve heat acquisition and heat rejection hardware including radiators, heat exchangers, and evaporators. The project has also been developing advanced phase change material heat sinks and performing a material compatibility assessment for a promising thermal control system working fluid. The to-date progress and lessons-learned from these development efforts will be discussed throughout the paper.

Stephan, Ryan A.

2011-01-01

177

Crew Exploration Vehicle (CEV) Potable Water System Verification Description  

NASA Technical Reports Server (NTRS)

The Crew Exploration Vehicle (CEV), also known as Orion, will ferry a crew of up to six astronauts to the International Space Station (ISS), or a crew of up to four astronauts to the moon. The first launch of CEV is scheduled for approximately 2014. A stored water system on the CEV will supply the crew with potable water for various purposes: drinking and food rehydration, hygiene, medical needs, sublimation, and various contingency situations. The current baseline biocide for the stored water system is ionic silver, similar in composition to the biocide used to maintain quality of the water transferred from the Orbiter to the ISS and stored in Contingency Water Containers (CWCs). In the CEV water system, the ionic silver biocide is expected to be depleted from solution due to ionic silver plating onto the surfaces of the materials within the CEV water system, thus negating its effectiveness as a biocide. Since the biocide depletion is expected to occur within a short amount of time after loading the water into the CEV water tanks at the Kennedy Space Center (KSC), an additional microbial control is a 0.1 micron point of use filter that will be used at the outlet of the Potable Water Dispenser (PWD). Because this may be the first time NASA is considering a stored water system for longterm missions that does not maintain a residual biocide, a team of experts in materials compatibility, biofilms and point of use filters, surface treatment and coatings, and biocides has been created to pinpoint concerns and perform testing to help alleviate those concerns related to the CEV water system. Results from the test plans laid out in the paper presented to SAE last year (Crew Exploration Vehicle (CEV) Potable Water System Verification Coordination, 2008012083) will be detailed in this paper. Additionally, recommendations for the CEV verification will be described for risk mitigation in meeting the physicochemical and microbiological requirements on the CEV PWS.

Peterson, Laurie; DeVera, Jean; Vega, Leticia; Adam, Nik; Steele, John; Gazda, Daniel; Roberts, Michael

2009-01-01

178

Overview of an Integrated Medical System for Exploration Missions  

NASA Technical Reports Server (NTRS)

The Exploration Medical Capability (ExMC) element of the NASA Human Research Program (HRP) is charged with addressing the risk of unacceptable health and mission outcomes due to limitations of inflight medical capabilities. The Exploration Medical System Demonstration (EMSD) is a project within the ExMC element aimed at reducing this risk by improving the medical capabilities available for exploration missions. The EMSD project will demonstrate, on the ground and on ISS, the integration of several components felt to be essential to the delivery of medical care during long ]duration missions outside of low Earth orbit. The components of the EMSD include the electronic medical record, assisted medical procedure software, medical consumables tracking technology and RFID ] tagged consumables, video conferencing capability, ultrasound device and probes (ground demonstration only), peripheral biosensors, and the software to allow communication among the various components (middleware). This presentation seeks to inform our international partners of the goals and objectives of the EMSD and to foster collaboration opportunities related to this and future projects.

Watkins, Sharmila; Rubin, David

2013-01-01

179

The binarity of Herbig Ae/Be stars observed with Adaptive Optics and spectroscopy. A study of the triple system TY CrA  

NASA Astrophysics Data System (ADS)

Multiplicity is a major issue in stellar astrophysics. Firstly, any stellar formation theory must explain the large abundance of multiple systems among Main Sequence and young low-mass T Tauri stars. Secondly, binary studies allow the direct determination of physical parameters. In the case of Herbig Ae/Be (HAeBe) stars, the binarity status is not well known; furthermore, direct mass determination are required to test stellar evolution models for these young intermediate mass objects. The first part of the thesis presents the results of a systematic search for HAeBe binaries in both hemispheres. Two complementary techniques were used to cover a large range of orbital period P: high angular resolution imaging with Adaptive Optics (AO) (binary separation ? between 0.12'' and few arcseconds, i.e. P ? many years), and high resolution visible spectroscopy to study short orbital period (P ?few hours to few months). Among the 68 HAeBe stars observed with ADONIS--ESO and PUEO--CFH AO instruments, 30 binaries (18 discovered) have been detected. 42 HAeBe stars have been surveyed with the CES--ESO and 'ELODIE, AURéLIE--OHP spectrographs. Radial velocity variations were found in 7 targets (4 are new spectroscopic binaries, 3 d. < P < 166 d.). In addition, the 7Li 6 708 Å absorption line (absent feature in simple HAeBe stars spectra) indicates the presence of a cooler companion in 6 HAeBe spectrum binaries, 4 of which are new detections. The observed visual binary frequency for HAeBe stars is of the order of 50%. For short period spectroscopic binaries (P < 100 days), the observed frequency is about 10%. Considering observational bias effects, these estimates are regarded as lower limits for the true HAeBe binary frequency. Based on our multi-color AO images, spectral types of twenty-two visual companions have been determined. A trend is found such that companions of Ae stars are low-mass T Tauri stars (spectral type K--M), while companions of Be stars are intermediate mass stars (A--F). Companions usually have no infrared excess, nor do primaries with massive companions. Furthermore, X-ray emission in some HAeBe stars may well be explained by the presence of a T Tauri companion. However, because of bias effects, great care must be taken about these issues, and complementary observations are needed. Our observations provide clues for binary formation theories, but while fragmentation and capture via a circumstellar disk seem plausible mechanisms, disk instabilities and stellar capture scenarios cannot be ruled out. The second part of the thesis is devoted to the study of TY CrA, the unique triple spectroscopic system among Herbig Ae/Be stars. We found this previously known eclipsing binary to be also a spectroscopic binary of SB2 type (P = 2.9 days), and we obtained the first direct mass determination of an HAeBe star. The orbital motion of a third companion around the central binary has been monitored, and a complete dynamical model of the triple system has been made. Our theoretical investigations show that the stability of the hierarchical system is insured by tidal effects inside the central eclipsing binary. To explain the puzzling subsynchroneous rotation of the primary star, a peculiar orientation, in which the primary is seen pole-on and its rotational axis is perpendicular to its orbital axis, is proposed. The circumstellar environment of TY CrA has been studied. SWS, LWS--ISO data show polycyclic aromatic hydrocarbon emissions (some of them never observed from the ground in TY CrA), and O sc i 63, 146 microns and [C II] 158 micron emission lines. These features may well be explained by the presence of a compact HII region and a photodissociation region associated with TY CrA. Adaptive Optics images in the near infrared obtained with and without coronograph show that the dusty environment must be confined very close to the star (< 0.5'' = 65 AU at 130pc).

Corporon, Patrice

1998-03-01

180

An inertial fusion propulsion scheme for solar system exploration  

NASA Technical Reports Server (NTRS)

The paper analyzes a novel fusion scheme that combines the favorable aspects of both inertial and magnetic confinement approaches as a propulsion device for potential application in solar system exploration. An appropriate set of equations for the plasma dynamics and the magnetic nozzle is used to assess the system's propulsive capability by applying the results to a round trip mission to Mars. It is found that such a device would allow a massive vehicle to make the journey in less than five months. It is shown that catalyzed deuterium-deuterium fuel results in a somewhat poorer propulsion performance than deuterium-tritium though at a significantly lower neutron production. The velocity increment generated by this system and the corresponding trip time are in excellent agreement with the predictions of Irving and Blum (1959).

Kammash, Terry; Galbraith, David L.

1991-01-01

181

Mission architecture decision support system for robotic lunar exploration  

NASA Astrophysics Data System (ADS)

It is common practice in the landing site decision process for planetary or lunar exploration to limit the choice of sites to locations that strictly meet the technical and safety requirements of the lander. The science objective is ultimately implemented within the operational requirements of the mission strategy. In this paper, we present a study that derives the technical requirements of the landing strategy by considering proposed landing sites. The study reviewed the objectives of the future robotic exploration of the Moon and proposed targets from the Apollo era to our time. Three types of strategies are defined, namely, rover missions, immobile landing stations, and impacting probes. The capabilities and restrictions of each system are taken into account and compared to the science objectives of the proposed landing sites. A Geographic Information System (GIS) with lunar datasets was developed and the methodology was implemented. The study concludes with a description of the resulting mission scenarios that were assigned to the targets. The technical requirements for each landing system to fulfil these scientific objectives are derived and the feasibility, based on the technological readiness, is discussed.

Weiss, P.; Yung, K. L.

2009-10-01

182

Grading NASA's Solar System Exploration Program: A Midterm Report  

NASA Technical Reports Server (NTRS)

The Committee on Assessing the Solar System Exploration Program has reviewed NASA's progress to date in implementing the recommendations made in the National Research Council's (NRC's) solar system exploration decadal survey covering the period 2003-2013, New Frontiers in the Solar System, and in its Mars Architecture report, Assessment of NASA s Mars Architecture 2007-2016. The committee assessed NASA's progress with respect to each individual recommendation in these two reports, assigning an academic-style grade, explaining the rationale for the grade and trend, and offering recommendations for improvement. The committee generally sought to develop recommendations in cases where it determined that the grade, the trend, or both were worrisome and that the achievement of a decadal survey recommendation would require some kind of corrective action on NASA's part. This usually meant that the committee sought to offer a recommendation when the grade was a "C" or lower. However, the committee did offer recommendations in connection with some higher grades when it believed that minor corrective action was possible and desirable. More importantly, the committee did not offer recommendations for some of the activities given lower grades, particularly in the enabling technologies area (Chapter 6), because the committee determined that only the restoration of funding and the development of a strategic technology development program would solve these problems.

2008-01-01

183

Gravity waves in the thermosphere observed by the AE satellites  

NASA Technical Reports Server (NTRS)

Atmospheric Explorer (AE) satellite data were used to investigate the spectra characteristics of wave-like structure observed in the neutral and ionized components of the thermosphere. Power spectral analysis derived by the maximum entropy method indicate the existence of a broad spectrum of scale sizes for the fluctuations ranging from tens to thousands of kilometers.

Gross, S. H.; Reber, C. A.; Huang, F. T.

1983-01-01

184

Performance Assessment of the Exploration Water Recovery System  

NASA Technical Reports Server (NTRS)

A new water recovery system architecture designed to fulfill the National Aeronautics and Space Administration s (NASA) Space Exploration Policy has been tested at the Marshall Space Flight Center (MSFC). This water recovery system architecture evolved from the current state-of-the-art system developed for the International Space Station (ISS). Through novel integration of proven technologies for air and water purification, this system promises to elevate existing system optimization. The novel aspect of the system is twofold. First, volatile organic compounds (VOC) are removed from the cabin air via catalytic oxidation in the vapor phase, prior to their absorption into the aqueous phase. Second, vapor compression distillation (VCD) technology processes the condensate and hygiene waste streams in addition to the urine waste stream. Oxidation kinetics dictate that removing VOCs from the vapor phase is more efficient. Treating the various waste streams by VCD reduces the load on the expendable ion exchange and adsorption media which follows, as well as the aqueous-phase catalytic oxidation process further downstream. This paper documents the results of testing this new architecture.

Carter. D. Layne; Tabb, David; Perry, Jay

2008-01-01

185

Crew Exploration Vehicle Potable Water System Verification Description  

NASA Technical Reports Server (NTRS)

A stored water system on the crew exploration vehicle (CEV) will supply the crew with potable water for: drinking and food rehydration, hygiene, medical needs, sublimation, and various contingency situations. The current baseline biocide for the stored water system is ionic silver, similar in composition to the biocide used to maintain the quality of the water, transferred from the orbiter to the International Space Station, stored in contingency water containers. In the CEV water system, a depletion of the ionic silver biocide is expected due to ionic silver-plating onto the surfaces of materials within the CEV water system, thus negating its effectiveness as a biocide. Because this may be the first time NASA is considering a stored water system for long-term missions that do not maintain a residual biocide, a team of experts in materials compatibility, biofilms and point-of-use filters, surface treatment and coatings, and biocides has been created to pinpoint concerns and perform the testing that will help alleviate concerns related to the CEV water system.

Tuan, George; Peterson, Laurie J.; Vega, Leticia M.

2010-01-01

186

A personal airbag system for the Orion Crew Exploration Vehicle  

NASA Astrophysics Data System (ADS)

Airbag-based methods for crew impact attenuation have been highlighted as a potential simple, lightweight means of enabling safe land-landings for the Orion Crew Exploration Vehicle, and the next generation of ballistic shaped spacecraft. To investigate the feasibility of this concept during a nominal 7.62 m/s Orion landing, a full-scale personal airbag system 24% lighter than the Orion baseline has been developed, and subjected to 38 drop tests on land. Through this effort, the system has demonstrated the ability to maintain the risk of injury to an occupant during a 7.85 m/s, 0° impact angle land-landing to within the NASA specified limit of 0.5%. In accomplishing this, the personal airbag system concept has been proven to be feasible. Moreover, the obtained test results suggest that by implementing anti-bottoming airbags to prevent direct contact between the system and the landing surface, the system performance during landings with 0° impact angles can be further improved, by at least a factor of two. Additionally, a series of drop tests from the nominal Orion impact angle of 30° indicated that severe injury risk levels would be sustained beyond impact velocities of 5 m/s. This is a result of the differential stroking of the airbags within the system causing a shearing effect between the occupant seat structure and the spacecraft floor, removing significant stroke from the airbags.

Do, Sydney; de Weck, Olivier

2012-12-01

187

AmeriFlux Site and Data Exploration System  

NASA Astrophysics Data System (ADS)

The AmeriFlux network was established in 1996. The network provides continuous observations of ecosystem-level exchanges of CO2, water, energy and momentum spanning diurnal, synoptic, seasonal, and interannual time scales. The current network, including both active and inactive sites, consists of 141 sites in North, Central, and South America. The Carbon Dioxide Information Analysis Center (CDIAC) at Oak Ridge National Laboratory (ORNL) provides data management support for the AmeriFlux network including long-term data storage and dissemination. AmeriFlux offers a broad suite of value-added data products: Level 1 data products at 30 minute or hourly time intervals provided by the site teams, Level 2 data processed by CDIAC and Level 3 and 4 files created using CarboEurope algorithms. CDIAC has developed a relational database to house the vast array of AmeriFlux data and information and a web-based interface to the database, the AmeriFlux Site and Data Exploration System (http://ameriflux.ornl.gov), to help users worldwide identify, and more recently, download desired AmeriFlux data. AmeriFlux and CDIAC offer numerous value-added AmeriFlux data products (i.e., Level 1-4 data products, biological data) and most of these data products are or will be available through the new data system. Vital site information (e.g., location coordinates, dominant species, land-use history) is also displayed in the new system. The data system provides numerous ways to explore and extract data. Searches can be done by site, location, measurement status, available data products, vegetation types, and by reported measurements just to name a few. Data can be accessed through the links to full data sets reported by a site, organized by types of data products, or by creating customized datasets based on user search criteria. The new AmeriFlux download module contains features intended to ease compliance of the AmeriFlux fair-use data policy, acknowledge the contributions of submitting investigators, inform AmeriFlux investigators of users of their data, and facilitate meaningful usage statistics. Comprehensive site descriptions are available via the same interface along with site-related publications and data visualization functionality. This presentation reflects the present state and functionality of the AmeriFlux Site and Data Exploration System as well as future plans for expansion. For example, future plans call for expansion of the relational database to house similar data from large-scale ecosystem experiments (e.g., FACE, NGEE - Next Generation Ecosystem Experiment) and inclusion of enhanced query capabilities (e.g., sorting data via day and night).

Krassovski, M.; Boden, T.; Yang, B.; Jackson, B.

2011-12-01

188

Bicarbonate homeostasis in excitable tissues: role of AE3 Cl?/HCO3? exchanger and carbonic anhydrase XIV interaction  

PubMed Central

Bicarbonate transport and metabolism are key elements of normal cellular function. Two alternate transcripts of anion exchanger 3 (AE3), full-length (AE3fl) and cardiac (AE3c), are expressed in central nervous system (CNS), where AE3 catalyzes electroneutral Cl?/HCO3? exchange across the plasma membrane of neuronal and glial cells of CNS. Anion exchanger isoforms, AE3fl and AE3c, associate with the carbonic anhydrases (CA) CAII and CAIV, forming a HCO3? transport metabolon, to maximize HCO3? flux across the plasma membrane. CAXIV, with catalytic domain anchored to the extracellular surface, is also expressed in CNS. Here physical association of AE3 and CAXIV was examined by coimmunoprecipitation experiments, using mouse brain and retinal lysates. CAXIV immunoprecipitated with anti-AE3 antibody, and both AE3 isoforms were immunoprecipitated using anti-CAXIV antibody, indicating CAXIV and AE3 interaction in the CNS. Confocal images revealed colocalization of CAXIV and AE3 in Müller and horizontal cells, in the mouse retina. Cl?/HCO3? exchange activity of AE3fl was investigated in transiently transfected human embryonic kidney 293 cells, using intracellular fluorescence measurements of BCECF, to monitor intracellular pH. CAXIV increased the rate of AE3fl-mediated HCO3? transport by up to 120%, which was suppressed by the CA inhibitor acetazolamide. Association of AE3 and CAXIV may represent a mechanism to enhance disposal of waste CO2 and to balance pH in excitable tissues.

Casey, Joseph R.; Sly, William S.; Shah, Gul N.

2009-01-01

189

Exploration of geothermal systems using hyperspectral thermal infrared remote sensing  

NASA Astrophysics Data System (ADS)

Visible near infrared (VNIR), short-wave infrared (SWIR), and thermal infrared (TIR) remote sensing has long been used for geothermal exploration. Specific focus on the TIR region (8-12 ?m) has resulted in major-rock-forming mineral classes being identified and their areal percentages to be more easily mapped due in part to the linear mixing behavior of TIR emission. To understand the mineral compositional and thermal distribution of active geothermal surfaces systems, hyperspectral TIR data from the Spatially Enhanced Broadband Array Spectrograph System (SEBASS) airborne sensor were acquired over the Salton Sea, CA geothermal fields by The Aerospace Corporation on March 26, 2009 and April 6, 2010. SEBASS collects 128 wavelength channels at ~ 1 m spatial resolution. Such high resolution data are rarely available for this type of scientific analysis and enabled the identification of rare mineral assemblages associated with the geothermally-active areas. One surface unit with a unique spectrum, believed to be a magnesium sulfate of unknown hydration state, was identified for the first time in the SEBASS data. The abundance and distribution of this mineral varied between 2009 and 2010 likely due to the precipitation conditions. Data obtained by the SEBASS sensor were also regressed to the 32 channel spectral resolution of the Mineral and Gas Identifier (MAGI) airborne sensor in order to test sensitivity limits. At this lower spectral resolution, all surface minerals were still effectively identified and therefore validated data at MAGI resolution are still very effective for accurate surface compositional mapping. A similar approach used at active geothermal areas in other semi-arid regions around the world has the potential to better characterize transient mineralogy, identify "indicators minerals", understand the influence of surface and ground water, and ultimately to locate new geothermal targets for future exploration. Furthermore, new Mineral and Gas Identification (MAGI) data serve as an excellent precursor for future spaceborne TIR data such as the system proposed for the Hyperspectral Infrared Imager (HyspIRI) instrument.

Reath, Kevin A.; Ramsey, Michael S.

2013-09-01

190

Benefit of Small Radioisotope Power Systems for NASA Exploration Missions  

NASA Astrophysics Data System (ADS)

The increased use of smaller spacecraft over the last decade, in combination with studies of potential science applications, has suggested the need for Radioisotope Power Systems (RPSs) yielding much lower power levels than the 100 watt-scale devices used in the past. Small milliwatt to multiwatt-scale RPS units have the potential to extend the capability of small science payloads and instruments, and to enable many new mission applications. Such units could also find application in future human exploration missions involving use of monitoring stations and autonomous devices, similar to the ALSEP units deployed on the Moon during the Apollo program. Although flight-qualified RPS units in this size and power range do not presently exist, their potential to support a broad range of exploration tasks has led NASA and the Department of Energy (DOE) to consider the development of small-RPS units such that they might be available for missions by the early part of next decade. This paper summarizes the results of activities to date and provides possible options for future development.

Schmidt, George R.; Abelson, Robert D.; Wiley, Robert L.

2005-02-01

191

(abstract) Airborne Emission Spectrometer (AES)  

NASA Technical Reports Server (NTRS)

AES is a low-cost analog of the TES downlooking modes. Because AES operates at ambient temperature, limb-viewing is not possible. The first flight of AES took place in April 1994 on the NASA P3B aircraft out of Wallops Island, VA. While planned as an engineering test flight, spectra were successfully acquired both over the Atlantic Ocean and the area of the Great Dismal Swamp on the Virginia-North Carolina border. At this writing (July 1994), a second series of flights on the NASA DC8 aircraft out of Ames RC,CA is in progress. By the time of the workshop, a third series using the NASA C130 should have been accomplished.

Beer, Reinhard

1994-01-01

192

Mission building blocks for outer solar system exploration.  

NASA Technical Reports Server (NTRS)

Description of the technological building blocks required for exploring the outer planets with maximum scientific yields under stringent resource constraints. Two generic spacecraft types are considered: the Mariner and the Pioneer. Following a discussion of the outer planet mission constraints, the evolutionary development of spacecraft, probes, and propulsion building blocks is presented. Then, program genealogies are shown for Pioneer and Mariner missions and advanced propulsion systems to illustrate the soundness of a program based on spacecraft modification rather than on the development of new spacecraft for each mission. It is argued that, for minimum costs, technological advancement should occur in an evolutionary manner from mission to mission. While this strategy is likely to result in compromises on specific missions, the realization of the overall objectives calls for an advance commitment to the entire mission series.

Herman, D.; Tarver, P.; Moore, J.

1973-01-01

193

UWB Tracking System Design for Lunar/Mars Exploration  

NASA Technical Reports Server (NTRS)

This paper describes a design effort for a prototype ultra-wideband (UWB) tracking system that is currently under development at NASA Johnson Space Center (JSC). The system is being studied for use in tracking of lunar/Mars rovers during early exploration missions when satellite navigation systems are not available. The UWB technology is exploited to implement the tracking system due to its properties such as high data rate, fine time resolution, low power spectral density, and multipath immunity. A two-cluster prototype design using commercially available UWB products is proposed to implement the Angle Of Arrival (AOA) tracking methodology in this research effort. An AOA technique using the Time Difference Of Arrival (TDOA) information is utilized for location estimation in the prototype system, not only to exploit the precise time resolution possible with UWB signals, but also to eliminate the need for synchronization between the transmitter and the receiver. After the UWB radio at each cluster is used to obtain the TDOA estimates from the UWB signal sent from the target, the TDOA data is converted to AOA data to find the angle of arrival, assuming this is a far field application. Since the distance between two clusters is known, the target position is computed by a simple triangulation. Simulations show that the average tracking error at a range of 610 meters is 2.7595 meters, less than 0.5% of the tracking range. Outdoor tests to track the SCOUT vehicle (The Science Crew Operations and Utility Testbed) near the Meteor Crater, Flagstaff, Arizona were performed on September 12-13, 2005. The tracking performance was obtained with less than 1% tracking error at ranges up to 2000 feet. No RF interference with on-board GPS, video, voice and telemetry systems was detected. Outdoor tests demonstrated the UWB tracking capability.

Ni, Jianjun; Arndt, Dickey; Ngo, Phong; Phan, Chau; Gross, Julia

2006-01-01

194

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration  

NASA Technical Reports Server (NTRS)

A number of problems related to the design, construction and evaluation of an autonomous roving planetary vehicle and its control and operating systems intended for an unmanned exploration of Mars are studied. Vehicle configuration, dynamics, control, systems and propulsion; systems analysis; terrain sensing and modeling and path selection; and chemical analysis of samples are included.

1974-01-01

195

Space Codesign: A SystemC Framework for Fast Exploration of Hardware\\/Software Systems  

Microsoft Academic Search

Abstract—Electronic System Level has ,brought new abstractions for designing systems, which most designers are not familiar with. The Space Codesign™ SystemC design framework,allows ,designers to easily ,model hardware\\/software-based systems, starting from a high level model and refining down to the chip. We propose a rapid system prototyping toolset that permits co-monitoring of specifications, effortless platform exploration for hardware\\/software partitioning and

El Mostapha Aboulhamid

196

The inner zone electron model AE-5  

NASA Technical Reports Server (NTRS)

A description is given of the work performed in the development of the inner radiation zone electron model, AE-5. A complete description of the omnidirectional flux model is given for energy thresholds E sub T in the range 4.0 E sub T/(MeV) 0.04 and for L values in the range 2.8 L 1.2 for an epoch of October 1967. Confidence codes for certain regions of B-L space and certain energies are given based on data coverage and the assumptions made in the analysis. The electron model programs that can be supplied to a user are referred to. One of these, a program for accessing the model flux at arbitrary points in B-L space and arbitrary energies, includes the latest outer zone electron model and proton model. The model AE-5, is based on data from five satellites, OGO 1, OGO 3, 1963-38C, OV3-3, and Explorer 26, spanning the period December 1964 to December 1967.

Teague, M. J.; Vette, J. I.

1972-01-01

197

Solar Power System Evaluated for the Human Exploration of Mars  

NASA Technical Reports Server (NTRS)

The electric power system is a crucial element of any mission for the human exploration of the Martian surface. The bulk of the power generated will be delivered to crew life support systems, extravehicular activity suits, robotic vehicles, and predeployed in situ resource utilization (ISRU) equipment. In one mission scenario, before the crew departs for Mars, the ISRU plant operates for 435 days producing liquefied methane and oxygen for ascent-stage propellants and water for crew life support. About 200 days after ISRU production is completed, the crew arrives for a 500-day surface stay. In this scenario, the power system must operate for a total of 1130 days (equivalent to 1100 Martian "sols"), providing 400 MW-hr of energy to the ISRU plant and up to 18 kW of daytime user power. A photovoltaic power-generation system with regenerative fuel cell (RFC) energy storage has been under study at the NASA Glenn Research Center at Lewis Field. The conceptual power system is dominated by the 4000- m2 class photovoltaic array that is deployed orthogonally as four tent structures, each approximately 5 m on a side and 100-m long. The structures are composed of composite members deployed by an articulating mast, an inflatable boom, or rover vehicles, and are subsequently anchored to the ground. Array panels consist of thin polymer membranes with thin-film solar cells. The array is divided into eight independent electrical sections with solar cell strings operating at 600 V. Energy storage is provided by regenerative fuel cells based on hydrogen-oxygen proton exchange membrane technology. Hydrogen and oxygen reactants are stored in gaseous form at 3000 psi, and the water produced is stored at 14.7 psi. The fuel cell operating temperature is maintained by a 40-m2 deployable pumped-fluid loop radiator that uses water as the working fluid. The power management and distribution (PMAD) architecture features eight independent, regulated 600-Vdc channels. Power management and distribution power cables use various gauges of copper conductors with ethylene tetrafluoroethylene insulation. To assess power system design options and sizing, we developed a dedicated Fortran code to predict detailed power system performance and estimate system mass. This code also modeled the requisite Mars surface environments: solar insolation, Sun angles, dust storms, dust deposition, and thermal and ultraviolet radiation. Using this code, trade studies were performed to assess performance and mass sensitivities to power system design parameters (photovoltaic array geometry and orientation) and mission parameters (landing date and landing site latitude, terrain slope, and dust storm activity). Mission analysis cases were also run. Power results are shown in this graph for an analysis case with a September 1, 2012, landing date; 18.95 North latitude landing site; two seasonal dusts storms; and tent arrays. To meet user load requirements and the ISRU energy requirement, an 8-metric ton (MT) power system and 4000-m2 photovoltaic array area were required for the assumed advanced CuInS2 thin-film solar cell technology. In this figure, the top curve is the average daytime photovoltaic array power, the middle curve is average daytime user load power, and the bottom curve is nighttime power. At mission day 1, daytime user power exceeds 120 kW before falling off to 80 kW at the end of the mission. Throughout the mission, nighttime user power is set to the nighttime power requirement. In this analysis, "nighttime" is defined as the 13- to 15-hr period when array power output is below the daytime power requirement. During dust storms, power system capability falls off dramatically so that by mission day 900, a daily energy balance cannot be maintained. Under these conditions, the ISRU plant is placed in standby mode, and the regenerative fuel cell energy storage is gradually discharged to meet user loads.

Kerslake, Thomas W.

2000-01-01

198

IBEX: Exploring the Edge of Our Solar System  

NSDL National Science Digital Library

This is a poster that outlines the major mission highlights of the Interstellar Boundary Explorer, or IBEX, mission, a Small Explorer Earth-orbiting spacecraft that is mapping the distant boundary between the solar wind from our Sun and the interstellar medium, the material between the stars. This poster complements other informal education materials related to the IBEX spacecraft.

199

Differential Fault Analysis against AES192 and AES256 with Minimal Faults  

Microsoft Academic Search

The naive implementation of AES is known to be vulnerable to Differential Fault Analysis (DFA). We can find the key of AES-128 (AES with 128-bit key) with one pair of correct and faulty cipher texts. Recently several works on the extension of the attack to AES with 192 and 256-bit key have been published. Due to the longer key size

Chong Hee Kim

2010-01-01

200

Future NASA solar system exploration activities: A framework for international cooperation  

NASA Technical Reports Server (NTRS)

The goals and approaches for planetary exploration as defined for the NASA Solar System Exploration Program are discussed. The evolution of the program since the formation of the Solar System Exploration Committee (SSEC) in 1980 is reviewed and the primary missions comprising the program are described.

French, Bevan M.; Ramlose, Terri; Briggs, Geoffrey A.

1992-01-01

201

Radio Aurora Explorer: Mission science and radar system  

NASA Astrophysics Data System (ADS)

The Radio Aurora Explorer (RAX) satellite is the first of several satellites funded under the NSF CubeSat-based Space Weather and Atmospheric Research Program. RAX is a ground-to-space bi-static radar remote sensing experiment designed to measure and understand the causes of meter-scale ionospheric irregularities. Also known as field-aligned irregularities (FAI), such non-thermal, coherent fluctuations of electron density occur in response to strong ionospheric flows or plasma density gradients during geomagnetic disturbances and are considered a space weather concern due to disruption to communication and navigation signals. The RAX CubeSat was launched in November 2010 and conducted a single experiment in coordination with the Poker Flat Incoherent Scatter Radar. Due to geophysical inactivity, e.g., lack of strong ionospheric electric fields and low ionospheric densities, no FAI were expected or observed. However, the radar receiver payload operation was successfully demonstrated, including the capability to sense signals as low as -110 dBm, the capability of transmitter-receiver synchronization and accurate ranging, processing of 1.2 GB of raw radar data on board in less than 1 hour, and the downlink of the science results within three-four passes. Analysis of the payload data shows that the noise level is sufficiently low. Although the interference level is a concern, it does not appear to significantly limit the measurements. Toward the end of December 2010, the solar power system gradually degraded and the mission terminated in early February 2011 after prolonged loss of contact with the satellite. Meanwhile, RAX II was launched in October 2011 to a polar orbit. This paper describes the RAX science and radar system and presents the results from the first experiment conducted.

Bahcivan, H.; Cutler, J. W.

2012-04-01

202

Fossil-Fuel C02 Emissions Database and Exploration System  

NASA Astrophysics Data System (ADS)

The Carbon Dioxide Information Analysis Center (CDIAC) at Oak Ridge National Laboratory (ORNL) quantifies the release of carbon from fossil-fuel use and cement production at global, regional, and national spatial scales. The CDIAC emission time series estimates are based largely on annual energy statistics published at the national level by the United Nations (UN). CDIAC has developed a relational database to house collected data and information and a web-based interface to help users worldwide identify, explore and download desired emission data. The available information is divided in two major group: time series and gridded data. The time series data is offered for global, regional and national scales. Publications containing historical energy statistics make it possible to estimate fossil fuel CO2 emissions back to 1751. Etemad et al. (1991) published a summary compilation that tabulates coal, brown coal, peat, and crude oil production by nation and year. Footnotes in the Etemad et al.(1991) publication extend the energy statistics time series back to 1751. Summary compilations of fossil fuel trade were published by Mitchell (1983, 1992, 1993, 1995). Mitchell's work tabulates solid and liquid fuel imports and exports by nation and year. These pre-1950 production and trade data were digitized and CO2 emission calculations were made following the procedures discussed in Marland and Rotty (1984) and Boden et al. (1995). The gridded data presents annual and monthly estimates. Annual data presents a time series recording 1° latitude by 1° longitude CO2 emissions in units of million metric tons of carbon per year from anthropogenic sources for 1751-2008. The monthly, fossil-fuel CO2 emissions estimates from 1950-2008 provided in this database are derived from time series of global, regional, and national fossil-fuel CO2 emissions (Boden et al. 2011), the references therein, and the methodology described in Andres et al. (2011). The data accessible here take these tabular, national, mass-emissions data and distribute them spatially on a one degree latitude by one degree longitude grid. The within-country spatial distribution is achieved through a fixed population distribution as reported in Andres et al. (1996). This presentation introduces newly build database and web interface, reflects the present state and functionality of the Fossil-Fuel CO2 Emissions Database and Exploration System as well as future plans for expansion.

Krassovski, M.; Boden, T.; Andres, R. J.; Blasing, T. J.

2012-12-01

203

Exploring the Earth System through online interactive models  

NASA Astrophysics Data System (ADS)

Upper level Earth Science students commonly have a strong background of mathematical training from Math courses, however their ability to use mathematical models to solve Earth Science problems is commonly limited. Their difficulty comes, in part, because of the nature of the subject matter. There is a large body of background ';conceptual' and ';observational' understanding and knowledge required in the Earth Sciences before in-depth quantification becomes useful. For example, it is difficult to answer questions about geological processes until you can identify minerals and rocks and understand the general geodynamic implications of their associations. However, science is fundamentally quantitative. To become scientists students have to translate their conceptual understanding into quantifiable models. Thus, it is desirable for students to become comfortable with using mathematical models to test hypotheses. With the aim of helping to bridging the gap between conceptual understanding and quantification I have started to build an interactive teaching website based around quantitative models of Earth System processes. The site is aimed at upper-level undergraduate students and spans a range of topics that will continue to grow as time allows. The mathematical models are all built for the students, allowing them to spend their time thinking about how the ';model world' changes in response to their manipulation of the input variables. The web site is divided into broad topics or chapters (Background, Solid Earth, Ocean and Atmosphere, Earth history) and within each chapter there are different subtopic (e.g. Solid Earth: Core, Mantle, Crust) and in each of these individual webpages. Each webpage, or topic, starts with an introduction to the topic, followed by an interactive model that the students can use sliders to control the input to and watch how the results change. This interaction between student and model is guided by a series of multiple choice questions that the student answers and immediately gets feedback whether the answer is correct or not. This way the students can ensure they understand the concepts before moving on. A discussion forum for the students to discuss the topics is in development and each page has a feedback option to allow both numerical (1-10) and written feedback on how useful the webpage was. By the end of exploring any given process students are expected to understand how the different parameters explored by the model interact to control the results. They should appreciate why the controlling equations look the way they do (all equations needed to develop the models are present in the introduction) and how these interact to control the results. While this is no substitute to students undertaking the calculations for themselves this approach allows a much wider range of topics to be explored quantitatively than if the students have to code all models themselves.

Coogan, L. A.

2013-12-01

204

Role of AE2 for pHi regulation in biliary epithelial cells  

PubMed Central

The Cl?/HCO?3anion exchanger 2 (AE2) is known to be involved in intracellular pH (pHi) regulation and transepithelial acid-base transport. Early studies showed that AE2 gene expression is reduced in liver biopsies and blood mononuclear cells from patients with primary biliary cirrhosis (PBC), a disease characterized by chronic non-suppurative cholangitis associated with antimitochondrial antibodies (AMA) and other autoimmune phenomena. Microfluorimetric analysis of the Cl?/HCO?3 anion exchange (AE) in isolated cholangiocytes showed that the cAMP-stimulated AE activity is diminished in PBC compared to both healthy and diseased controls. More recently, it was found that miR-506 is upregulated in cholangiocytes of PBC patients and that AE2 may be a target of miR-506. Additional evidence for a pathogenic role of AE2 dysregulation in PBC was obtained with Ae2?/?a,b mice, which develop biochemical, histological, and immunologic alterations that resemble PBC (including development of serum AMA). Analysis of HCO?3 transport systems and pHi regulation in cholangiocytes from normal and Ae2?/?a,b mice confirmed that AE2 is the transporter responsible for the Cl?/HCO?3exchange in these cells. On the other hand, both Ae2+/+a,b and Ae2?/?a,b mouse cholangiocytes exhibited a Cl?-independent bicarbonate transport system, essentially a Na+-bicarbonate cotransport (NBC) system, which could contribute to pHi regulation in the absence of AE2.

Concepcion, Axel R.; Lopez, Maria; Ardura-Fabregat, Alberto; Medina, Juan F.

2013-01-01

205

NASA Langley Research Center Systems Analysis & Concepts Directorate Participation in the Exploration Systems Architecture Study  

NASA Technical Reports Server (NTRS)

The NASA Langley Research Center (LaRC) Systems Analysis & Concepts Directorate (SACD) began studying human exploration missions beyond low Earth orbit (LEO) in the year 1999. This included participation in NASA s Decadal Planning Team (DPT), the NASA Exploration Team (NExT), Space Architect studies and Revolutionary Aerospace Systems Concepts (RASC) architecture studies that were used in formulating the new Vision for Space Exploration. In May of 2005, NASA initiated the Exploration Systems Architecture Study (ESAS). The primary outputs of the ESAS activity were concepts and functional requirements for the Crewed Exploration Vehicle (CEV), its supporting launch vehicle infrastructure and identification of supporting technology requirements and investments. An exploration systems analysis capability has evolved to support these functions in the past and continues to evolve to support anticipated future needs. SACD had significant roles in supporting the ESAS study team. SACD personnel performed the liaison function between the ESAS team and the Shuttle/Station Configuration Options Team (S/SCOT), an agency-wide team charged with using the Space Shuttle to complete the International Space Station (ISS) by the end of Fiscal Year (FY) 2010. The most significant of the identified issues involved the ability of the Space Shuttle system to achieve the desired number of flights in the proposed time frame. SACD with support from the Kennedy Space Center performed analysis showing that, without significant investments in improving the shuttle processing flow, that there was almost no possibility of completing the 28-flight sequence by the end of 2010. SACD performed numerous Lunar Surface Access Module (LSAM) trades to define top level element requirements and establish architecture propellant needs. Configuration trades were conducted to determine the impact of varying degrees of segmentation of the living capabilities of the combined descent stage, ascent stage, and other elements. The technology assessment process was developed and implemented by SACD as the ESAS architecture was refined. SACD implemented a rigorous and objective process which included (a) establishing architectural functional needs, (b) collection, synthesis and mapping of technology data, and (c) performing an objective decision analysis resulting in technology development investment recommendations. The investment recommendation provided budget, schedule, and center/program allocations to develop required technologies for the exploration architecture, as well as the identification of other investment opportunities to maximize performance and flexibility while minimizing cost and risk. A summary of the trades performed and methods utilized by SACD for the Exploration Systems Mission Directorate (ESAS) activity is presented along with how SACD is currently supporting the implementation of the Vision for Space Exploration.

Keyes, Jennifer; Troutman, Patrick A.; Saucillo, Rudolph; Cirillo, William M.; Cavanaugh, Steve; Stromgren, Chel

2006-01-01

206

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration  

NASA Technical Reports Server (NTRS)

Investigation of problems related to control of a mobile planetary vehicle according to a systematic plan for the exploration of Mars has been undertaken. Problem areas receiving attention include: (1) overall systems analysis; (2) vehicle configuration and dynamics; (3) toroidal wheel design and evaluation; (4) on-board navigation systems; (5) satellite-vehicle navigation systems; (6) obstacle detection systems; (7) terrain sensing, interpretation and modeling; (8) computer simulation of terrain sensor-path selection systems; and (9) chromatographic systems design concept studies. The specific tasks which have been undertaken are defined and the progress which has been achieved during the period July 1, 1971 to December 31, 1971 is summarized.

Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Smith, E. J.; Yerazunis, S. W.

1971-01-01

207

How to Extend the Capabilities of Space Systems for Long Duration Space Exploration Systems  

NASA Technical Reports Server (NTRS)

For sustainable Exploration Missions the need exists to assemble systems-of-systems in space, on the Moon or on other planetary surfaces. To fulfill this need new and innovative system architecture is needed that can be satisfied with the present lift capability of existing rocket technology without the added cost of developing a new heavy lift vehicle. To enable ultra-long life missions with minimum redundancy and lighter mass the need exists to develop system soft,i,are and hardware reconfigurability, which enables increasing functionality and multiple use of launched assets while at the same time overcoming any components failures. Also the need exists to develop the ability to dynamically demate and reassemble individual system elements during a mission in order to work around failed hardware or changed mission requirements. Therefore to meet the goals of Space Exploration Missions in hiteroperability and Reconfigurability, many challenges must be addressed to transform the traditional static avionics architecture into architecture with dynamic capabilities. The objective of this paper is to introduce concepts associated with reconfigurable computer systems; review the various needs and challenges associated with reconfigurable avionics space systems; provide an operational example that illustrates the needs applicable to either the Crew Exploration Vehicle or a collection of "Habot like" mobile surface elements; summarize the approaches that address key challenges to acceptance of a Flexible, Intelligent, Modular and Affordable reconfigurable avionics space system.

Marzwell, Neville I.; Waterman, Robert D.; KrishnaKumar, Kalmanje; Waterman, Susan J.

2005-01-01

208

Phylogenetic and temporal dynamics of human immunodeficiency virus type 1 CRF01_AE in China.  

PubMed

To explore the epidemic history of HIV-1 CRF01_AE in China, 408 fragments of gag gene sequences of CRF01_AE sampled in 2002-2010 were determined from different geographical regions and risk populations in China. Phylogenetic analysis indicates that the CRF01_AE sequences can be grouped into four clusters, suggesting that at least four genetically independent CRF01_AE descendants are circulating in China, of which two were closely related to the isolates from Thailand and Vietnam. Cluster 1 has the most extensive distribution in China. In North China, cluster 1 and cluster 4 were mainly transmitted through homosexuality.The real substance of the recent HIV-1 epidemic in men who have sex with men(MSM) of North China is a rapid spread of CRF01_AE, or rather two distinctive natives CRF01_AE.The time of the most recent common ancestor (tMRCA) of four CRF01_AE clusters ranged from the years 1990.9 to 2003.8 in different regions of China. This is the first phylogenetic and temporal dynamics study of HIV-1 CRF01_AE in China. PMID:23365653

Ye, Jingrong; Xin, Ruolei; Yu, Shuangqing; Bai, Lishi; Wang, Weishi; Wu, Tingchen; Su, Xueli; Lu, Hongyan; Pang, Xinghuo; Yan, Hong; Feng, Xia; He, Xiong; Zeng, Yi

2013-01-01

209

Massive young disks around Herbig Ae stars  

NASA Astrophysics Data System (ADS)

Context. Herbig Ae stars (HAe) are the precursors of Vega-type systems, hence crucial objects in planet formation studies. Thus far, only a few disks associated with HAe stars have been studied using millimetre interferometers. Aims: Our aim is to determine the dust evolution and the lifetime of the disks associated with Herbig Ae stars. Methods: We imaged the continuum emission at ~3 mm and ~1.3 mm of the Herbig Ae/Be stars BD+61154, RR Tau, VY Mon, and LkH? 198 using the Plateau de Bure Interferometer (PdBI). These stars are in the upper end of the stellar mass range of the Herbig Ae stars (M? > 3 M?). Our measurements were used to complete the spectral energy distribution (SED). The modelling of the SED, in particular the FIR-mm part, allows us to determine the masses and dust properties of these disks. Results: We detected the disks associated with BD+61154, RR Tau, and VY Mon with disk masses of 0.35 M?, 0.05 M?, and 0.40 M?, respectively. The disk around LkH? 198 was not detected with an upper limit to the disk mass of 0.004 M?. We detected, however, the disks associated with the younger stellar objects LkH? 198-IR and LkH? 198-mm that are located in the vicinity of LkH? 198. The fitting of the mm part of the SED reveal that the grains in the mid-plane of the disks around BD+61154, RR Tau, and VY Mon have sizes of ~1-1000 ?m. Therefore, grains have not grown to centimetre sizes in these disks yet. Conclusions: These massive (M? > 3 M?) and young (~1 Myr) HAe stars are surrounded by massive (? 0.04 M?) disks with grains of micron-millimetre sizes. Although grain growth is proceeding in these disks, their evolutionary stage is prior to the formation of planetesimals. These disks are less evolved than those detected around T Tauri and Herbig Be stars. Based on observations carried out with the IRAM Plateau de Bure Interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain).The data used for the maps of Fig. 1 (FITS files) are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/531/A50

Boissier, J.; Alonso-Albi, T.; Fuente, A.; Berné, O.; Bachiller, R.; Neri, R.; Ginard, D.

2011-07-01

210

In-Situ Production of Solar Power Systems for Exploration  

NASA Technical Reports Server (NTRS)

Current proposals for developing an extended human presence, beyond space stations, on the Moon and Mars increasingly consider the processing of non-terrestrial materials essential for keeping the Earth launch burden reasonable. Utilization of in-situ resources for construction of lunar and Mars bases will initially require assessment of resource availability followed by the development of economically acceptable and technically feasible extractive processes. In regard to materials processing and fabrication the lower gravity level on the Moon (0.125 g) and Mars (0.367 g) will dramatically change the presently accepted hierarchy of materials in terms of specific properties, a factor which must be understood and exploited. Furthermore, significant changes are expected in the behavior of liquid materials during processing. In casting, for example, mold filling and associated solidification processes have to be reevaluated. Finally microstructural development and therefore material properties, presently being documented through on-going research in microgravity science and applications, needs to be understood and scaled to the reduced gravity environments. One of the most important elements of a human planetary base is power production. Lunar samples and geophysical measurements returned by the Apollo missions provide detailed data on the composition and physical characteristics of the lunar materials and environment. Based on this knowledge and extrapolations of terrestrial industrial experience it is clear that several types of solar-to-electric converters can be manufactured on the Moon. It is conceivable that well over 90% of a solar-to- electric power system could be made from lunar materials. Production and utilization of photovoltaic devices for solar energy production on Earth is primarily driven by the market economy. On Earth a production plant for photovoltaic devices is intimately linked to the planets massive industrial base. A selection of off the shelf refined materials are available as well as cheap fast transportation on demand. The processes takes place (except for the few seconds reprieve in shot towers etc.) under one gravity, with solar radiation significantly modulated by weather, and under conditions where one atmosphere is free and high vacuum is cumbersome and expensive. Off Earth, on lunar or Mars bases, the cost of photovoltaic power is driven by transport costs - Earth launch, deep space transport, landing on the planetary surface. Thus there is a premium for processes that are materials self-sufficient or for closed loop in-situ processes. The lack of differentiated ores on the Moon, and lack of explored minerals on Mars and interplanetary space give a premium to universal/non-ore-specific mineral extractive processes. Initially a semiconductor/photovoltaic production facility will build on no conveniently located industrial base, further increasing the premium on closed loop self sufficient processes.

Curreri, Peter A.; Criswell, David R.

1999-01-01

211

Automatic flow-injection system for the determination of heavy metals in sewage sludge by microwave digestion and detection by inductively coupled plasma-atomic emission spectrometry (MW-ICP/AES).  

PubMed

Results are shown obtained in the optimization of an automatic flow injection system that combines microwave digestion with atomic spectrometric detection (FAAS, ICP/AES) for the determination of heavy metals in sewage sludge. Digestion is performed by preparing a suspension of the sample in 1.5 mol/l HNO(3) and making it flow through a PTFE capillary tube placed inside a conventional microwave oven. The effects of the length and inner diameter of the capillary tube, as well as that of the pumping rate, have been studied in order to find the experimental conditions that allow a quantitative elemental recovery in the shortest period of time possible. The optimization study was carried out on a certified sample (BCR No. 146), and the elements determined were Zn, Cu, Pb, Cd, Ni and Cr. The experimental data (percent recovery vs. digestion time) have been fitted to a mathematical model in order to quantify the influence of each of the variables studied. The optimized procedure (MW-ICP/AES) has been applied to one ordinary and one certified sewage sludge sample. In comparison with the conventional methods of sewage sludge analysis, the one proposed is less time consuming, while being equally precise and accurate. PMID:15045433

Bordera, L; Hernandis, V; Canals, A

1996-05-01

212

New techniques in astrodynamics for moon systems exploration  

NASA Astrophysics Data System (ADS)

ESA and NASA scientific missions to the Jupiter and Saturn systems will answer fundamental questions on the habitability of icy worlds. The missions include unprecedented challenges, as the spacecraft will be placed in closed, stable orbits near the surface of the moons. This thesis presents methods to design trajectories that tour the moons and ultimately insert the spacecraft into orbits around them, while mitigating the mission costs and/or risks. A first technique is the endgame, a sequence of moon flyby preceding the orbit insertion. Historically, the endgame is designed with two approaches with different results: the vinfinity-leveraging transfer (VILT) approach leads to high-Deltav (hundreds of m/s), short time-of-flight (months) endgames, while the multi-body approach leads to low-Deltav (tens of m/s), long time-of-flight (years) endgames. This work analyzes and develops both approaches. We introduce a fast design method to automatically compute VILT endgames, which were previously designed in an ad-hoc manner. We also derive an important simple quadrature formula for the minimum Deltav attainable with this approach. This formula is the first important result of this work, as it provides a lower bound for assessment studies. We explain and develop the complex multi-body approach introducing the Tisserand-Poincare (T-P) graph, which is the second important result of this work. It provides a link between the two approaches, and shows the intersections between low-energy trajectories around different moons. With the T-P graph we design a five-month transfer between low-altitude orbits at Europa and Ganymede, using almost half the Deltav of the Hohmann transfer. We then focus on missions to low-mass moons, like Enceladus. We show that nontangent VILT (an extension of the traditional VILT) significantly reduce the Deltav while maintaining a satisfactory transfer time (< 4 years in the Saturn system). With a new design method we compute a 52 gravity-assist trajectory from Titan to Enceladus. The time of flight is 2.7 years, and the Deltav is almost 10 times better then the Titan-Enceladus Hohmann-like transfer. This trajectory and the design method are the third important contribution of this work; they enable a new class of missions which were previously considered unfeasible. Finally we study the capture problem, which seeks chaotic trajectories with multiple orbit insertion opportunities. We explore the solution space extending the design techniques used by ESA for the BepiColombo mission capture to Mercury. Such problems are better modeled in the spatial, elliptic, restricted three-body problem, which we analyze in detail. We define new regions of motions and to compute new families of periodic orbits and their stability properties. This analysis is the fourth important contribution of this work. Finally we show that capture trajectories shadow the manifolds of special periodic and quasi periodic orbits. This is the last important contribution of this report, as if both explains the complex dynamics of capture trajectories, and suggests new ways to design them.

Campagnola, Stefano

213

The Role of Astrobiology in Solar System Exploration: Report from the NASA Astrobiology Institute to the NRC Solar-System Exploration Steering Group  

Microsoft Academic Search

Astrobiology as related to solar-system exploration addresses far more than just the search for life in our solar system. It is about understanding the planets in our solar system as representing different outcomes in their formation, the nature of processes that affected those outcomes, and how those same processes might have operated elsewhere. It is about understanding planetary evolution and

B. M. Jakosky; D. J. Des Marais

2001-01-01

214

MobiVis: A Visualization System for Exploring Mobile Data  

Microsoft Academic Search

The widespread use of mobile devices brings opportunities to cap- ture large-scale, continuous information about human behavior. Mobile data has tremendous value, leading to business opportuni- ties, market strategies, security concerns, etc. Visual analytics sys- tems that support interactive exploration and discovery are needed to extracting insight from the data. However, visual analysis of complex social-spatial-temporal mobile data presents several

Zeqian Shen; Kwan-liu Ma

2008-01-01

215

Atmosphere explorer and the IMS  

NASA Technical Reports Server (NTRS)

The Atmosphere Explorer (AE) program provided assistance to participants in the International Magnetosphere Study (IMS). The AE program, which began about 1970 employed three spacecraft in three complementary orbits. The program initiated a concept of a common data base, which is, a data base shared by all the participating investigators, to facilitate the correlation of the measured parameters. The immediate goal of the AE program has been study of the thermosphere, giving particular attention to photochemistry. Three satellites, AE-C, D, and E, were launched into orbits of 68 deg, 90 deg, and 19 deg inclination respectively in December 1973, October 1975, and November 1975. An instrument complement description is provided, and the AE data base is discussed.

Spencer, N. W.

1982-01-01

216

Exploring User Satisfaction in a Tutorial Dialogue System.  

National Technical Information Service (NTIS)

User satisfaction is a common evaluation metric in task-oriented dialogue systems, whereas tutorial dialogue systems are often evaluated in terms of student learning gain. However, user satisfaction is also important for such systems, since it may predict...

G. Campbell J. D. Moore M. O. Dzikovska N. Steinhauser

2011-01-01

217

Fission Technology for Exploring and Utilizing the Solar System  

NASA Technical Reports Server (NTRS)

Fission technology can enable rapid, affordable access to any point in the solar system. Potential fission-based transportation options include bimodal nuclear thermal rockets, high specific energy propulsion systems, and pulsed fission propulsion systems. In-space propellant re-supply enhances the effective performance of all systems, but requires significant infrastructure development. Safe, timely, affordable utilization of first-generation space fission propulsion systems will enable the development of more advanced systems. First generation space systems will build on over 45 years of US and international space fission system technology development to minimize cost,

Houts, Mike; VanDyke, Melissa; Godfroy, Tom; Pedersen, Kevin; Martin, James; Dickens, Ricky; Salvail, Pat; Hrbub, Ivana; Schmidt, George R. (Technical Monitor)

2000-01-01

218

Exploration System Mission Directorate and Constellation Program Support for Analogue Missions  

NASA Technical Reports Server (NTRS)

Vision: To create a cross-cutting Earth-based program to minimize cost and risk while maximizing the productivity of planetary exploration missions, by supporting precursor system development and carrying out system integration, testing, training, and public engagement as an integral part of the Vision for Space Exploration.

Hoffman, Stephen J.; Voels, Stephen A.; Gerty, Christopher E.

2008-01-01

219

Near-Infrared Interferometric Images of the Solar System Sized Disk Surrounding the Herbig Ae/Be Star MWC 349A  

NASA Technical Reports Server (NTRS)

We present images of the Herbig Ae/Be star MWC 349A at 1.65 and 2.27, and 3.08 micrometers, reconstructed from complex visibility data obtained with an aperture masking interferometric technique on the Keck I telescope. These images have an approximately elliptical shape, and are consistent with the expected shape of a nearly edge-on Keplerian disk. Visibility data were fitted with uniform ellipses with major axes 36 +/- 2, 47 +/- 2, and 62 +/- 1 mas, respectively. The axial ratio of the ellipses is approximately 0.5 +/- 0.1, and the major axis is at a position angle of 100 +/- 3 degrees, consistent with the position angle of the dark lane observed previously in the Very Large Array (VLA) radio continuum maps at 8 and 22 GHz, perpendicular to the symmetry axis of the bipolar lobes of H66(alpha) recombination line emission, and consistent with positions of the recombination line maser spots at 1.3 mm. At an assumed distance of 1.2 kpc, the linear sizes of the disk are 44 and 57 AU at 1.65 and 2.2 micrometers, respectively. The disk is the presumed source of ionized material in the bipolar outflow and ultracompact HII region around the star.

Danchi, W.C.; Tuthill, P. G.; Monnier, J. D.; Fisher, Richard (Technical Monitor)

2000-01-01

220

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration  

NASA Technical Reports Server (NTRS)

Problems related to the design and control of a mobile planetary vehicle to implement a systematic plan for the exploration of Mars are reported. Problem areas include: vehicle configuration, control, dynamics, systems and propulsion; systems analysis, terrain modeling and path selection; and chemical analysis of specimens. These tasks are summarized: vehicle model design, mathematical model of vehicle dynamics, experimental vehicle dynamics, obstacle negotiation, electrochemical controls, remote control, collapsibility and deployment, construction of a wheel tester, wheel analysis, payload design, system design optimization, effect of design assumptions, accessory optimal design, on-board computer subsystem, laser range measurement, discrete obstacle detection, obstacle detection systems, terrain modeling, path selection system simulation and evaluation, gas chromatograph/mass spectrometer system concepts, and chromatograph model evaluation and improvement.

Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Smith, E. V.; Yerazunis, S. W.

1973-01-01

221

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration  

NASA Technical Reports Server (NTRS)

The following tasks related to the design, construction, and evaluation of a mobile planetary vehicle for unmanned exploration of Mars are discussed: (1) design and construction of a 0.5 scale dynamic vehicle; (2) mathematical modeling of vehicle dynamics; (3) experimental 0.4 scale vehicle dynamics measurements and interpretation; (4) vehicle electro-mechanical control systems; (5) remote control systems; (6) collapsibility and deployment concepts and hardware; (7) design, construction and evaluation of a wheel with increased lateral stiffness, (8) system design optimization; (9) design of an on-board computer; (10) design and construction of a laser range finder; (11) measurement of reflectivity of terrain surfaces; (12) obstacle perception by edge detection; (13) terrain modeling based on gradients; (14) laser scan systems; (15) path selection system simulation and evaluation; (16) gas chromatograph system concepts; (17) experimental chromatograph separation measurements and chromatograph model improvement and evaluation.

Frederick, D. K.; Lashmet, P. K.; Moyer, W. R.; Sandor, G. N.; Shen, C. N.; Smith, E. J.; Yerazunis, S. W.

1973-01-01

222

Exploration Planetary Surface Structural Systems: Design Requirements and Compliance  

NASA Technical Reports Server (NTRS)

The Lunar Surface Systems Project developed system concepts that would be necessary to establish and maintain a permanent human presence on the Lunar surface. A variety of specific system implementations were generated as a part of the scenarios, some level of system definition was completed, and masses estimated for each system. Because the architecture studies generally spawned a large number of system concepts and the studies were executed in a short amount of time, the resulting system definitions had very low design fidelity. This paper describes the development sequence required to field a particular structural system: 1) Define Requirements, 2) Develop the Design and 3) Demonstrate Compliance of the Design to all Requirements. This paper also outlines and describes in detail the information and data that are required to establish structural design requirements and outlines the information that would comprise a planetary surface system Structures Requirements document.

Dorsey, John T.

2011-01-01

223

LOX/LH2 propulsion system for exploration mission  

NASA Astrophysics Data System (ADS)

A LOX/LH2 propulsion system used for injecting payloads into lunar transfer orbit or interplanetary orbit was studied. The propulsion system was a kind of Orbit Transfer Vehicle (OTV) propulsion system. The propulsion system and spacecraft would be launched into low earth parking orbit by the H-II rocket. After separation from the H-II rocket second stage, the propulsion system would inject the spacecraft into earth escape trajectory. A restart capability would be required for the propulsion system to inject the payload into lunar orbit.

Ito, Takahiro; Mori, Takashige

224

System-level exploration for pareto-optimal configurations in parameterized systems-on-a-chip  

Microsoft Academic Search

In this work, we provide a technique for efficiently exploring the configuration space of a parameterized system-on-a-chip (SOC) architecture to find all Pareto-optimal configurations. These configurations represent the range of meaningful power and performance tradeoffs that are obtainable by adjusting parameter values for a fixed application mapped onto the SOC architecture. Our approach extensively prunes the potentially large configuration space

Tony Givargis; Frank Vahid; Jörg Henkel

2001-01-01

225

The FUSE satellite is prepped for prelaunch processing at Hangar AE, Cape Canaveral Air Station  

NASA Technical Reports Server (NTRS)

Workers in Hangar AE, Cape Canaveral Air Station, begin removing the plastic covering from NASA's Far Ultraviolet Spectroscopic Explorer (FUSE) satellite before prelaunch processing. FUSE will undergo a functional test of its systems, followed by installation of the flight batteries and solar arrays. Tests are also scheduled for the communications and data systems linking FUSE with the spacecraft control center at The Johns Hopkins University, Baltimore, Md. FUSE was developed and will be operated by The Johns Hopkins University under contract to Goddard Space Flight Center, Greenbelt, Md. FUSE will investigate the origin and evolution of the lightest elements in the universe - hydrogen and deuterium. In addition, the FUSE satellite will examine the forces and process involved in the evolution of the galaxies, stars and planetary systems by investigating light in the far ultraviolet portion of the electromagnetic spectrum. The launch aboard a Boeing Delta II rocket is targeted for May 20 at Launch Complex 17.

1999-01-01

226

The FUSE satellite is prepped for prelaunch processing at Hangar AE, Cape Canaveral Air Station  

NASA Technical Reports Server (NTRS)

Workers in Hangar AE, Cape Canaveral Air Station, get ready to remove the protective shipping cover from NASA's Far Ultraviolet Spectroscopic Explorer (FUSE) satellite for prelaunch processing. FUSE will undergo a functional test of its systems, followed by installation of the flight batteries and solar arrays. Tests are also scheduled for the communications and data systems linking FUSE with the spacecraft control center at The Johns Hopkins University, Baltimore, Md. FUSE was developed and will be operated by The Johns Hopkins University under contract to Goddard Space Flight Center, Greenbelt, Md. FUSE will investigate the origin and evolution of the lightest elements in the universe - hydrogen and deuterium. In addition, the FUSE satellite will examine the forces and process involved in the evolution of the galaxies, stars and planetary systems by investigating light in the far ultraviolet portion of the electromagnetic spectrum. The launch aboard a Boeing Delta II rocket is targeted for May 20 at Launch Complex 17.

1999-01-01

227

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

228

Chromosome isolation by flow sorting in Aegilops umbellulata and Ae. comosa and their allotetraploid hybrids Ae. biuncialis and Ae. geniculata.  

PubMed

This study evaluates the potential of flow cytometry for chromosome sorting in two wild diploid wheats Aegilops umbellulata and Ae. comosa and their natural allotetraploid hybrids Ae. biuncialis and Ae. geniculata. Flow karyotypes obtained after the analysis of DAPI-stained chromosomes were characterized and content of chromosome peaks was determined. Peaks of chromosome 1U could be discriminated in flow karyotypes of Ae. umbellulata and Ae. biuncialis and the chromosome could be sorted with purities exceeding 95%. The remaining chromosomes formed composite peaks and could be sorted in groups of two to four. Twenty four wheat SSR markers were tested for their position on chromosomes of Ae. umbellulata and Ae. comosa using PCR on DNA amplified from flow-sorted chromosomes and genomic DNA of wheat-Ae. geniculata addition lines, respectively. Six SSR markers were located on particular Aegilops chromosomes using sorted chromosomes, thus confirming the usefulness of this approach for physical mapping. The SSR markers are suitable for marker assisted selection of wheat-Aegilops introgression lines. The results obtained in this work provide new opportunities for dissecting genomes of wild relatives of wheat with the aim to assist in alien gene transfer and discovery of novel genes for wheat improvement. PMID:22132127

Molnár, István; Kubaláková, Marie; Šimková, Hana; Cseh, András; Molnár-Láng, Márta; Doležel, Jaroslav

2011-01-01

229

NEXT Ion Propulsion System Configurations and Performance for Saturn System Exploration  

NASA Technical Reports Server (NTRS)

The successes of the Cassini/Huygens mission have heightened interest to return to the Saturn system with focused robotic missions. The desire for a sustained presence at Titan, through a dedicated orbiter and in-situ vehicle, either a lander or aerobot, has resulted in definition of a Titan Explorer flagship mission as a high priority in the Solar System Exploration Roadmap. The discovery of active water vapor plumes erupting from the tiger stripes on the moon Enceladus has drawn the attention of the space science community. The NASA's Evolutionary Xenon Thruster (NEXT) ion propulsion system is well suited to future missions to the Saturn system. NEXT is used within the inner solar system, in combination with a Venus or Earth gravity assist, to establish a fast transfer to the Saturn system. The NEXT system elements are accommodated in a separable Solar Electric Propulsion (SEP) module, or are integrated into the main spacecraft bus, depending on the mission architecture and performance requirements. This paper defines a range of NEXT system configurations, from two to four thrusters, and the Saturn system performance capability provided. Delivered mass is assessed parametrically over total trip time to Saturn. Launch vehicle options, gravity assist options, and input power level are addressed to determine performance sensitivities. A simple two-thruster NEXT system, launched on an Atlas 551, can deliver a spacecraft mass of over 2400 kg on a transfer to Saturn. Similarly, a four-thruster system, launched on a Delta 4050 Heavy, delivers more than 4000 kg spacecraft mass. A SEP module conceptual design, for a two thruster string, 17 kW solar array, configuration is characterized.

Benson, Scott W.; Riehl, John P.; Oleson, Steven R.

2007-01-01

230

Exploration of a "Closed System": The Galileo Thermometer  

NSDL National Science Digital Library

In this activity students will observe and try to interpret a "closed system," a system which allows the transfer of energy in and out, but not the exchange of material. They will realize that work can be done within the closed system as a result of the transfer of energy into the system even though nothing within the closed system was physically touched. Students will also exercise their understanding of density, and the relationships among density, volume and temperature. In addition, they develop their ability to make observations, a tentative interpretation (hypothesis) from those observations, and a plan to test that interpretation.

Kastens, Kim

231

Revised planetary protection policy for solar system exploration  

NASA Technical Reports Server (NTRS)

In order to control contamination of planets by terrestrial microorganisms and organic constituents, U.S. planetary missions have been governed by a planetary protection (or planetary quarantine) policy which has changed little since 1972. This policy has recently been reviewed in light of new information obtained from planetary exploration during the past decade and because of changes to, or uncertainties in, some parameters used in the existing quantitative approach. On the basis of this analysis, a revised planetary protection policy with the following key features is proposed: deemphasizing the use of mathematical models and quantitative analyses; establishing requirements for target planet/mission type (i.e., Orbiter, Lander, etc.) combinations; considering sample return missions a separate category; simplifying documentation; and imposing implementing procedures (i.e., trajectory biasing, cleanroom assembly, spacecraft sterilization, etc.) by exception, i.e., only if the planet/mission combination warrants such controls.

Devincenzi, D. L.; Stabekis, P. D.

1984-01-01

232

Life Support System Technologies for NASA Exploration Missions  

NASA Technical Reports Server (NTRS)

The Lunar Mars Life Support Test series successfully demonstrated integration and operation of advanced technologies for closed-loop life support systems, including physicochemical and biological subsystems. Increased closure was obtained when targeted technologies, such as brine dewatering subsystems, were added to further process life support system byproducts to recover resources. Physicochemical and biological systems can be integrated satisfactorily to achieve desired levels of closure. Imbalances between system components, such as differences in metabolic quotients between human crews and plants, must be addressed. Each subsystem or component that is added to increase closure will likely have added costs, ranging from initial launch mass, power, thermal, crew time, byproducts, etc., that must be factored into break even analysis. Achieving life support system closure while maintaining control of total mass and system complexity will be a challenge.

Ewert, Michael K.

2007-01-01

233

Small space reactor power systems for unmanned solar system exploration missions  

SciTech Connect

A preliminary feasibility study of the application of small nuclear reactor space power systems to the Mariner Mark II Cassini spacecraft/mission was conducted. The purpose of the study was to identify and assess the technology and performance issues associated with the reactor power system/spacecraft/mission integration. The Cassini mission was selected because study of the Saturn system was identified as a high priority outer planet exploration objective. Reactor power systems applied to this mission were evaluated for two different uses. First, a very small 1 kWe reactor power system was used as an RTG replacement for the nominal spacecraft mission science payload power requirements while still retaining the spacecraft's usual bipropellant chemical propulsion system. The second use of reactor power involved the additional replacement of the chemical propulsion system with a small reactor power system and an electric propulsion system. The study also provides an examination of potential applications for the additional power available for scientific data collection. The reactor power system characteristics utilized in the study were based on a parametric mass model that was developed specifically for these low power applications. The model was generated following a neutronic safety and operational feasibility assessment of six small reactor concepts solicited from U.S. industry. This assessment provided the validation of reactor safety for all mission phases and generatad the reactor mass and dimensional data needed for the system mass model.

Bloomfield, H.S.

1987-12-01

234

Small space reactor power systems for unmanned solar system exploration missions  

NASA Technical Reports Server (NTRS)

A preliminary feasibility study of the application of small nuclear reactor space power systems to the Mariner Mark II Cassini spacecraft/mission was conducted. The purpose of the study was to identify and assess the technology and performance issues associated with the reactor power system/spacecraft/mission integration. The Cassini mission was selected because study of the Saturn system was identified as a high priority outer planet exploration objective. Reactor power systems applied to this mission were evaluated for two different uses. First, a very small 1 kWe reactor power system was used as an RTG replacement for the nominal spacecraft mission science payload power requirements while still retaining the spacecraft's usual bipropellant chemical propulsion system. The second use of reactor power involved the additional replacement of the chemical propulsion system with a small reactor power system and an electric propulsion system. The study also provides an examination of potential applications for the additional power available for scientific data collection. The reactor power system characteristics utilized in the study were based on a parametric mass model that was developed specifically for these low power applications. The model was generated following a neutronic safety and operational feasibility assessment of six small reactor concepts solicited from U.S. industry. This assessment provided the validation of reactor safety for all mission phases and generatad the reactor mass and dimensional data needed for the system mass model.

Bloomfield, Harvey S.

1987-01-01

235

Space exploration and the history of solar-system volatiles  

Microsoft Academic Search

The thermochemical history of volatile substances in all solar-system planets, satellites, and planetoids is discussed extensively. The volatiles are viewed as an interface between the abiotic and biotic worlds and as a key to the history of bodies of the solar system. A flowsheet of processes and states is exhibited. Differences in bulk volatiles distribution between the planetary bodies and

F. P. Fanale

1976-01-01

236

Mated Flight Control Issues for Space Exploration Systems  

NASA Technical Reports Server (NTRS)

Several unique issues related to mated flight control have been broadly identified. These issues include redundancies in subsystems, controllability, command and control authority distribution, information flow across elements, and changes and variability in system characteristics due to variable mated configurations during operations. Architectural options for mated flight control are discussed in the context of evolving space systems.

Lim, Kyong B.; Markley, F. Landis; Whorton, Mark S.

2006-01-01

237

The Mars Exploration Rovers Descent Image Motion Estimation System  

Microsoft Academic Search

Descent image motion estimation system is the first machine-vision system for estimating lander velocity during planetary descent. Composed of sensors and software, DIMES features a descent imager, a radar altimeter, an inertial-measurement unit, and an algorithm for combining sensor measurements to estimate horizontal velocity - the speed across the planet's surface the lander travels as it descends. Although the sensors

Yang Cheng; Jay Goguen; Andrew Edie Johnson; Chris Leger; Larry Matthies; A. Miguel San Martin; Reg G. Willson

2004-01-01

238

Meeting the Challenges of Exploration Systems: Health Management Technologies for Aerospace Systems With Emphasis on Propulsion  

NASA Technical Reports Server (NTRS)

The constraints of future Exploration Missions will require unique Integrated System Health Management (ISHM) capabilities throughout the mission. An ambitious launch schedule, human-rating requirements, long quiescent periods, limited human access for repair or replacement, and long communication delays all require an ISHM system that can span distinct yet interdependent vehicle subsystems, anticipate failure states, provide autonomous remediation, and support the Exploration Mission from beginning to end. NASA Glenn Research Center has developed and applied health management system technologies to aerospace propulsion systems for almost two decades. Lessons learned from past activities help define the approach to proper ISHM development: sensor selection- identifies sensor sets required for accurate health assessment; data qualification and validation-ensures the integrity of measurement data from sensor to data system; fault detection and isolation-uses measurements in a component/subsystem context to detect faults and identify their point of origin; information fusion and diagnostic decision criteria-aligns data from similar and disparate sources in time and use that data to perform higher-level system diagnosis; and verification and validation-uses data, real or simulated, to provide variable exposure to the diagnostic system for faults that may only manifest themselves in actual implementation, as well as faults that are detectable via hardware testing. This presentation describes a framework for developing health management systems and highlights the health management research activities performed by the Controls and Dynamics Branch at the NASA Glenn Research Center. It illustrates how those activities contribute to the development of solutions for Integrated System Health Management.

Melcher, Kevin J.; Sowers, T. Shane; Maul, William A.

2005-01-01

239

Emergency Oxygen System Evaluation for Exploration PLSS Applications  

NASA Technical Reports Server (NTRS)

The Portable Life Support System (PLSS) emergency oxygen system is being reexamined for the next generation of suits. These suits will be used for transit to Low Earth Orbit, the Moon and to Mars as well as on the surface of the Moon and Mars. Currently, the plan is that there will be two different sets of suits, but there is a strong desire for commonality between them for construction purposes. The main purpose of this paper is to evaluate what the emergency PLSS requirements are and how they might best be implemented. Options under consideration are enlarging the tanks on the PLSS, finding an alternate method of storage/delivery, or providing additional O2 from an external source. The system that shows the most promise is the cryogenic oxygen system with a composite dewar which uses a buddy system to split the necessary oxygen between two astronauts.

Heather, Paul; Vonau, Walt, Jr.; Conger, Bruce

2006-01-01

240

Small Portable PEM Fuel Cell Systems for NASA Exploration Missions  

NASA Technical Reports Server (NTRS)

Oxygen-Hydrogen PEM-based fuel cell systems are being examined as a portable power source alternative in addition to advanced battery technology. Fuel cell power systems have been used by the Gemini, Apollo, and Space Shuttle programs. These systems have not been portable, but have been integral parts of their spacecraft, and have used reactants from a separate cryogenic supply. These systems typically have been higher in power. They also have had significant ancillary equipment sections that perform the pumping of reactants and coolant through the fuel cell stack and the separation of the product water from the unused reactant streams. The design of small portable fuel cell systems will be a significant departure from these previous designs. These smaller designs will have very limited ancillary equipment, relying on passive techniques for reactant and thermal management, and the reactant storage will be an integral part of the fuel cell system. An analysis of the mass and volume for small portable fuel cell systems was done to evaluate and quantify areas of technological improvement. A review of current fuel cell technology as well as reactant storage and management technology was completed to validate the analysis and to identify technology challenges

Burke, Kenneth A.

2005-01-01

241

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.

242

Exploration Systems Health Management Facilities and Testbed Workshop  

NASA Technical Reports Server (NTRS)

Presentation Agenda : (1) Technology Maturation Pipeline (The Plan) (2) Cryogenic testbed (and other KSC Labs) (2a) Component / Subsystem technologies (3) Advanced Technology Development Center (ATDC) (3a) System / Vehic1e technologies (4) EL V Flight Experiments (Flight Testbeds).

Wilson, Scott; Waterman, Robert; McCleskey, Carey

2004-01-01

243

Solar System Odyssey Mission: a Deep Space Gravity Explorer  

Microsoft Academic Search

The Solar System Odyssey mission was proposed in the frame of Cosmic Vision 2015-2025 call of proposal. It uses modern-day high-precision experimental techniques to test the laws of fundamental physics which determine dynamics in the solar system. It could lead to major discoveries by using demonstrated technologies. The mission proposes to perform a set of precision gravitation experiments from the

Bruno Christophe; Bernard Foulon; Pierre Touboul; Agnes Levy

2008-01-01

244

A Sustainable, Reliable Mission-Systems Architecture that Supports a System of Systems Approach to Space Exploration  

NASA Technical Reports Server (NTRS)

A mission-systems architecture based on a highly modular "systems of systems" infrastructure utilizing open-standards hardware and software interfaces as the enabling technology is absolutely essential for an affordable and sustainable space exploration program. This architecture requires (a) robust communication between heterogeneous systems, (b) high reliability, (c) minimal mission-to-mission reconfiguration, (d) affordable development, system integration, and verification of systems, and (e) minimum sustaining engineering. This paper proposes such an architecture. Lessons learned from the space shuttle program are applied to help define and refine the model.

Watson, Steve; Orr, Jim; O'Neil, Graham

2004-01-01

245

Far Ultraviolet Spectroscopic Explorer optical system: lessons learned  

NASA Astrophysics Data System (ADS)

The Far Ultraviolet Spectroscopic Explorer (FUSE) is a NASA astrophysics satellite designed to produce high resolution spectra in the far-ultraviolet (90.5-118.7 nm bandpass) with a high effective area (20-70 cm2) and low background detector. It was launched on a three-year mission in June 1999 aboard a Boeing Delta II rocket. The satellite has been performing routine science observations since December 1999. FUSE contains four co-aligned, normal incidence, off-axis parabolic primary mirrors which illuminate separate Rowland circle spectrograph channels equipped with holographically ruled diffraction gratings and microchannel plate detectors. Fine error sensors (slit jaw cameras) operating in the visible on two of the channels are used for target acquisition and guiding. The FUSE mission was first proposed in the late 1980s, and experienced several major conceptual changes prior to fabrication, assembly, and testing, which lasted from 1996 through 1999. During the program, we realized both positive and negative aspects to our design and processes that may apply to other space missions using telescopes and spectrographs. The specific topics we address are requirements, design, component specification, integration, and verification. We also discuss on-orbit alignment and focus. These activities were complicated by unexpected levels of motion between the optical elements, and the logistical problems associated with limited ground contact passes in low Earth orbit. We have developed methods to characterize the motions and mitigate their resultant effects on the science data through a combination of observing techniques and modifications to the data reduction software.

Conard, Steven J.; Barkhouser, Robert H.; Evans, Jordan P.; Friedman, Scott D.; Kruk, Jeffrey W.; Moos, H. Warren; Ohl, Raymond G.; Sahnow, David J.

2000-12-01

246

In-ice acoustic positioning system for the Enceladus Explorer  

NASA Astrophysics Data System (ADS)

The IceMole, a combination of melting and drilling probe, which is able to move and steer through ice and take samples while doing so, can be used to install instruments in ice. In addition to the inertial navigation system, the ice-craft will be equipped with an acoustic positioning system, composed of receivers in the probe itself and several emitters (pinger) on the glacier surface. It will determine the position of the IceMole by measuring the signal propagation time and trilateration, which requires a solid knowledge of the propagation of acoustic signals in ice. A method to determine these properties during the operation of the IceMole will be developed. Here we will give an overview over the goals of the project and the design of the IceMole. We will present the status of the development of the acoustic positioning system and show the results of simulations on the positioning accuracy.

Hoffmann, Ruth; EnEx Collaboration

2013-05-01

247

High-temperature nuclear closed Brayton cycle power conversion system for the space exploration initiative  

Microsoft Academic Search

The Space Exploration Initiative (SEI) has stated goals of colonizing the moon and conducting manned exploration of the planet Mars. Unlike previous ventures into space, both manned and unmanned, large quantities of electrical power will be required to provide the energy for lunar base sustenance and for highly efficient propulsion systems for the long trip to mars and return. Further,

Donald J. Brandes

1991-01-01

248

High-temperature nuclear closed Brayton cycle power conversion system for the Space Exploration Initiative  

Microsoft Academic Search

The Space Exploration Initiative has stated goals of colonizing the moon and conducting manned exploration of the planet Mars. Unlike previous ventures into space, both manned and unmanned, large quantities of electrical power will be required to provide the energy for lunar base sustenance and for highly efficient propulsion systems for the long trip to Mars and return. Further, the

Donald J. Brandes

1991-01-01

249

JUpiter ICy Moons Explorer (JUICE): The ESA L1 Mission to the Jupiter System  

NASA Astrophysics Data System (ADS)

The Jupiter Icy Moons Explorer (JUICE) mission has recently been selected by ESA as the first large mission within the Cosmic Visions 2015-2025 plan. We will introduce the mission that is being developed to thoroughly explore the Jupiter system with focus on the largest satellite, Ganymede.

Dougherty, M. K.; Grasset, O.; Erd, C.; Titov, D.; Bunce, E.; Coustenis, A.; Blanc, M.; Coates, A.; Drossart, P.; Fletcher, L.; Hussmann, H.; Jaumann, R.; Krupp, N.; Prieto-Ballesteros, O.; Tortora, P.; Tosi, F.; Van Hoolst, T.

2012-10-01

250

Wanderers in space. Exploration and discovery in the solar system.  

NASA Astrophysics Data System (ADS)

This book presents the results of a voyage of discovery in the solar system recording more than two decades of extraordinary accomplishments. It includes numerous photos from spacecraft as well as a few works of modern art. Contents: 1. Worlds in motion. 2. The Moon: stepping stone to the planets. 3. Mercury: a battered world. 4. Venus: the veiled planet. 5. The restless Earth. 6. Mars: the red desert. 7. Asteroids, meteors and meteorites. 8. Jupiter: a giant primitive world. 9. Saturn: lord of the rings. 10. Frozen worlds: Uranus, Neptune and Pluto. 11. Comets: icy wanderers. 12. Birth of the solar system.

Lang, K. R.; Whitney, C. A.

251

Exploring the Solar System with a Human Orrery  

NASA Astrophysics Data System (ADS)

One of the fundamental learning goals of introductory astronomy is for the students to gain some perspective on the scale and structure of the solar system. Many astronomy teachers have laid out the planets along a long strip of paper1 or across a school grounds or campus.2 Other activities that investigate the motion of the planets are often computer based,34 hiding the awe-inspiring distances between the planets. Our human orrery activity, adapted from the design at the Armagh Observatory in Ireland,567 combines the best of both approaches by creating a working model of the solar system that mimics both the scale and the motion of the planets.

Newbury, Peter

2010-12-01

252

Exploring performance of neutron guide systems using pinhole beam extraction  

NASA Astrophysics Data System (ADS)

We perform an optimization of pinhole neutron guide systems under systematically varying conditions. It is investigated how neutron guide systems consisting of a parabolic feeder inside the biological shielding followed by a pinhole and an elliptical guide perform with different pinhole sizes and divergence requirements. We have clarified in which situations such a guide system is a viable choice and when the parabolic feeder is necessary in terms of neutron transport. The advantage of this design is the reduction of background from fast thermal neutrons compared to a system without a pinhole, hence the smallest possible pinhole is of interest. It is found that instruments with divergence requirements of ±1.0° will have excellent neutron transport with a 3×3 cm2 pinhole, while lower divergence requirements of ±0.5° can do with a smaller pinhole of 2×2 cm2. The feeder effectively reduces the necessary pinhole size, and is especially beneficial for short instruments. In addition to these qualities, a feeder will often smoothen the divergence profile, mostly for longer instruments.

Bertelsen, Mads; Jacobsen, Henrik; Bengaard Hansen, Ursula; Hoffmann Carlsen, Henrik; Lefmann, Kim

2013-11-01

253

Space Exploration and the History of Solar-System Volatiles  

Microsoft Academic Search

The assemblage of volatiles degassed from each planetary object simultaneously reflects the preaccretion history of the solid solar-system material which accreted to produce that object and the internal differentiation history of the object. The key questions are: 1) What are the differences in bulk composition among planetary objects and how did they arise? and 2) How have volatiles within each

Fraser Fanale

1976-01-01

254

Trends in instrument systems for deep space exploration  

Microsoft Academic Search

In recent years there have been an increasing number of space science instruments that are being designed as integral elements in integrated instrument suites as opposed to stand-alone instruments. In fact, some instruments are becoming closely integrated with the mobility systems that carry them to their science targets. This higher level of integration has been motivated by both resource limitations

L. I. Dorsky

2001-01-01

255

Benefit of Small Radioisotope Power Systems for NASA Exploration Missions  

Microsoft Academic Search

The increased use of smaller spacecraft over the last decade, in combination with studies of potential science applications, has suggested the need for Radioisotope Power Systems (RPSs) yielding much lower power levels than the 100 watt-scale devices used in the past. Small milliwatt to multiwatt-scale RPS units have the potential to extend the capability of small science payloads and instruments,

George R. Schmidt; Robert D. Abelson; Robert L. Wiley

2005-01-01

256

Exploring Legacy Systems Using Types. Software Engineering (SEN).  

National Technical Information Service (NTIS)

We show how hypertext-based program understanding tools can achieve new levels of abstraction by using inferred type information for cases where the subject software system is written in a weakly typed language. We propose TYPEEXPLORER, a tool for browsin...

A. van Deursen L. M. F. Moonen

2000-01-01

257

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration  

NASA Technical Reports Server (NTRS)

A number of problems related to unmanned exploration of planets or other extraterrestrial bodies with Mars as a case in point were investigated. The design and evaluation of a prototype rover concept with emphasis on mobility, maneuverability, stability, control and propulsion is described along with the development of terrain sensor concepts and associated software for the autonomous control of any planetary rover. Results are applicable not only to the design of a mission rover but the vehicle is used as a test bed for the rigorous evaluation of alternative autonomous control systems.

Gisser, D. G.; Frederick, D. K.; Yerazunis, S. W.

1977-01-01

258

Bioinspired engineering of exploration systems: a horizon sensor/attitude reference system based on the dragonfly Ocelli for Mars exploration applications  

NASA Technical Reports Server (NTRS)

The intent of Bio-inspired Engineering of Exploration Systems (BEES) is to distill the principles found in successful, nature-tested mechanisms of specific crucial functions that are hard to accomplish by conventional methods, but accomplished rather deftly in nature by biological oganisms.

Thakoor, S.; Zornetzer, S.; Hine, B.; Chahl, J.; Stange, G.

2002-01-01

259

Space exploration and the history of solar-system volatiles  

NASA Technical Reports Server (NTRS)

The thermochemical history of volatile substances in all solar-system planets, satellites, and planetoids is discussed extensively. The volatiles are viewed as an interface between the abiotic and biotic worlds and as a key to the history of bodies of the solar system. A flowsheet of processes and states is exhibited. Differences in bulk volatiles distribution between the planetary bodies and between the interior, surface, and atmosphere of each body are considered, as well as sinks for volatiles in degassing. The volatiles-rich Jovian and Saturnian satellites, the effect of large-planet magnetosphere sweeps on nearby satellites, volatiles of asteroids and comets, and the crucial importance of seismic, gravity, and libration data are treated. A research program encompassing analysis of the elemental and isotopic composition of rare gas in atmospheres, assay of volatiles-containing phases in regoliths, and examination of present or past atmospheric escape/accretion processes is recommended.

Fanale, F. P.

1976-01-01

260

Situation exploration in a persistent surveillance system with multidimensional data  

NASA Astrophysics Data System (ADS)

There is an emerging need for fusing hard and soft sensor data in an efficient surveillance system to provide accurate estimation of situation awareness. These mostly abstract, multi-dimensional and multi-sensor data pose a great challenge to the user in performing analysis of multi-threaded events efficiently and cohesively. To address this concern an interactive Visual Analytics (VA) application is developed for rapid assessment and evaluation of different hypotheses based on context-sensitive ontology spawn from taxonomies describing human/human and human/vehicle/object interactions. A methodology is described here for generating relevant ontology in a Persistent Surveillance System (PSS) and demonstrates how they can be utilized in the context of PSS to track and identify group activities pertaining to potential threats. The proposed VA system allows for visual analysis of raw data as well as metadata that have spatiotemporal representation and content-based implications. Additionally in this paper, a technique for rapid search of tagged information contingent to ranking and confidence is explained for analysis of multi-dimensional data. Lastly the issue of uncertainty associated with processing and interpretation of heterogeneous data is also addressed.

Habibi, Mohammad S.

2013-03-01

261

Exploring the Outer Solar System with the ESSENCE Supernova Survey  

SciTech Connect

We report the discovery and orbital determination of 14 trans-Neptunian objects (TNOs) from the ESSENCE Supernova Survey difference imaging data set. Two additional objects discovered in a similar search of the SDSS-II Supernova Survey database were recovered in this effort. ESSENCE repeatedly observed fields far from the solar system ecliptic (-21{sup o} < {beta} < -5{sup o}), reaching limiting magnitudes per observation of I {approx} 23.1 and R {approx} 23.7. We examine several of the newly detected objects in detail, including 2003 UC{sub 414}, which orbits entirely between Uranus and Neptune and lies very close to a dynamical region that would make it stable for the lifetime of the solar system. 2003 SS{sub 422} and 2007 TA{sub 418} have high eccentricities and large perihelia, making them candidate members of an outer class of TNOs. We also report a new member of the 'extended' or 'detached' scattered disk, 2004 VN{sub 112}, and verify the stability of its orbit using numerical simulations. This object would have been visible to ESSENCE for only {approx}2% of its orbit, suggesting a vast number of similar objects across the sky. We emphasize that off-ecliptic surveys are optimal for uncovering the diversity of such objects, which in turn will constrain the history of gravitational influences that shaped our early solar system.

Becker, A.C.; /Washington U., Seattle, Astron. Dept.; Arraki, K.; /Washington U., Seattle, Astron. Dept.; Kaib, N.A.; /Washington U., Seattle, Astron. Dept.; Wood-Vasey, W.M.; /Harvard-Smithsonian Ctr. Astrophys.; Aguilera, C.; /Cerro-Tololo InterAmerican Obs.; Blackman, J.W.; /Australian Natl. U., Canberra; Blondin, S.; /Harvard-Smithsonian Ctr. Astrophys.; Challis, P.; /Harvard-Smithsonian Ctr. Astrophys.; Clocchiatti, A.; /Rio de Janeiro, Pont. U. Catol.; Covarrubias, R.; /Kyushu Sangyo U.; Damke, G.; /Cerro-Tololo InterAmerican Obs.; Davis, T.M.; /Bohr Inst. /Queensland U.; Filippenko, A.V.; /UC, Berkeley; Foley, R.J.; /UC, Berkeley; Garg, A.; /Harvard-Smithsonian Ctr. Astrophys. /Harvard U.; Garnavich, P.M.; /Notre Dame U.; Hicken, M.; /Harvard-Smithsonian Ctr. Astrophys. /Harvard U.; Jha, S.; /Harvard U. /SLAC; Kirshner, R.P.; /Harvard-Smithsonian Ctr. Astrophys.; Krisciunas, K.; /Notre Dame U. /Texas A-M; Leibundgut, B.; /Munich, Tech. U. /UC, Berkeley /NOAO, Tucson /Washington U., Seattle, Astron. Dept. /Fermilab /Harvard-Smithsonian Ctr. Astrophys. /Harvard U. /Chile U., Santiago /Ohio State U. /Cerro-Tololo InterAmerican Obs. /Harvard U. /Baltimore, Space Telescope Sci. /Johns Hopkins U. /Australian Natl. U., Canberra /Australian Natl. U., Canberra /Cerro-Tololo InterAmerican Obs. /Munich, Tech. U. /Harvard-Smithsonian Ctr. Astrophys. /Harvard U. /Cerro-Tololo InterAmerican Obs. /Texas A-M /Cerro-Tololo InterAmerican Obs.

2011-11-10

262

Exploring the D*? system within QCD sum rules  

NASA Astrophysics Data System (ADS)

We present a study of the D*? system made by using the method of QCD sum rules to determine the mass of possible resonances generated in the same system. Using isospin and spin projectors, we investigate the different configurations and obtain evidences for three D* mesons with isospin I=1/2, spin S=0, 1, 2 and with masses 2500±67, 2523±60, and 2439±119MeV, respectively. The last state can be associated with D2*(2460) (spin 2) listed by the Particle Data Group, while one of the first two might be related to D*(2640), with unknown spin parity. In the case of I=3/2 we also find evidences of three states with spin 0, 1, and 2, respectively, with masses 2467±82, 2420±128, and 2550±56MeV. The results for the sector I=1/2 and S=0, 1, 2, are intriguingly similar to a previous study of the D*? system based on effective field theories, supporting in this way a molecular picture for the resonances D*(2640) and D2*(2460), while the results for I=3/2 hint towards the existence of exotic mesons since a multiquark configuration is required to get the quantum numbers of the states found.

Martínez Torres, A.; Khemchandani, K. P.; Nielsen, M.; Navarra, F. S.; Oset, E.

2013-10-01

263

A Comparison of Electric Propulsion Systems for Mars Exploration  

NASA Technical Reports Server (NTRS)

Earth-Mars trajectories for multiple solar-powered spacecraft configurations were generated using Hall and ion propulsion systems utilizing the Direct Trajectory Optimization Method. Payload and power trades versus trip time were examined. Performance was compared for purely interplanetary flight and interplanetary flight with estimated spiral in to Mars orbit. Evaluating current ion and Hall thruster technologies, similar payload masses were delivered by each at equivalent trip times, but with the Hall thruster operating at a power level 10 kilowatts, on average, less than the ion thruster. The power difference for equivalent payload delivered should result in a significant cost savings.

Fiehler, Douglas; Oleson, Steve

2003-01-01

264

GSFC Information Systems Technology Developments Supporting the Vision for Space Exploration.  

National Technical Information Service (NTIS)

The Vision for Space Exploration will guide NASA's future human and robotic space activities. The broad range of human and robotic missions now being planned will require the development of new system-level capabilities enabled by emerging new technologie...

P. Hughes C. Dennehy G. Mosier D. Smith L. Rykowski

2005-01-01

265

NASA's Space Launch System: A Flagship for Exploration Beyond Earth's Orbit.  

National Technical Information Service (NTIS)

The National Aeronautics and Space Administration's (NASA) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is making progress toward delivering a new capability for exploration beyond Earth orbit in an austere economic clim...

T. A. May

2012-01-01

266

Waveform Analysis of AE in Composites  

NASA Technical Reports Server (NTRS)

Advanced, waveform based acoustic emission (AE) techniques have been developed to evaluate damage mechanisms in the testing of composite materials. This approach, more recently referred to as Modal AE, provides an enhanced capability to discriminate and eliminate noise signals from those generated by damage mechanisms. Much more precise source location can also be obtained in comparison to conventional, threshold crossing arrival time determination techniques. Two successful examples of the application of Modal AE are presented in this work. In the first, the initiation of transverse matrix cracking in cross-ply, tensile coupons was monitored. In these tests, it was documented that the same source mechanism, matrix cracking, can produce widely different AE signal amplitudes dependent on laminate stacking sequence and thickness. These results, taken together with well known propagation effects of attenuation and dispersion of AE signals in composite laminates, cast further doubt on the validity of simple amplitude or amplitude distribution analysis for AE source determination. For the second example, delamination propagation in composite ring specimens was monitored. Pressurization of these composite rings is used to simulate the stresses in a composite rocket motor case. AE signals from delamination propagation were characterized by large amplitude flexural plate mode components which have long signal durations because of the large dispersion of this mode.

Prosser, William H.

1998-01-01

267

Small Explorer Data System MIL-STD-1773 fiber optic bus  

NASA Technical Reports Server (NTRS)

The MIL-STD-1773 Fiber Optic Data Bus as implemented in the GSFC Small Explorer Data System (SEDS) for the Small Explorer Program is described. It provides an overview of the SEDS MIL-STD-1773 bus components system design considerations, reliability figures, acceptance and qualification testing requirements, radiation requirements and tests, error handling considerations, and component heritage. The first mission using the bus will be launched in June of 1992.

Flanegan, Mark; Label, Ken

1992-01-01

268

Exploration of the solar system - achievements and future plans in NASA's programme.  

NASA Astrophysics Data System (ADS)

Culminating with the Voyager 2 encounter with Uranus in January and a multifaceted program of ground-based and spacecraft observations of comet Halley during the spring, the year 1986 has capped a quarter century of NASA solar system exploration. Although our understanding of the solar system has been greatly increased, the data obtained thus far has served primarily to whet the appetite for further, more detailed exploration.

Brunk, W.

1986-11-01

269

A drill-soil system modelization for future Mars exploration  

NASA Astrophysics Data System (ADS)

This paper presents a first approach to the problem of modeling a drilling process to be carried on in the space environment by a dedicated payload. Systems devoted to work in space present very strict requirements in many different fields such as thermal response, electric power demand, reliability and so on. Thus, models devoted to the operational behaviour simulation represent a fundamental help in the design phase and give a great improvement in the final product quality. As the required power is the crucial constraint within drilling devices, the tool-soil interaction modelization and simulation are finalized to the computation of the power demand as a function of both the drill and the soil parameters. An accurate study of the tool and the soil separately has been firstly carried on and, secondly their interaction has been analyzed. The Dee-Dri system, designed by Tecnospazio and to be part of the lander components in the NASA's Mars Sample Return Mission, has been taken as the tool reference. The Deep-Drill system is a complex rotary tool devoted to the soil perforation and sample collection; it has to operate in a Martian zone made of rocks similar to the terrestrial basalt, then the modelization is restricted to the interaction analysis between the tool and materials belonging to the rock set. The tool geometric modelization has been faced by a finite element approach with a Langrangian formulation: for the static analysis a refined model is assumed considering both the actual geometry of the head and the rod screws; a simplified model has been used to deal with the dynamic analysis. The soil representation is based on the Mohr-Coulomb crack criterion and an Eulerian approach has been selected to model it. However, software limitations in dealing with the tool-soil interface definition required assuming a Langrangian formulation for the soil too. The interaction between the soil and the tool has been modeled by extending the two-dimensional Nishimatsu's theory for rock cutting for rotating perforation tools. A fine analysis on f.e.m. element choice for each part of the tool is presented together with static analysis results. The dynamic analysis results are limited to the first impact phenomenon between the rock and the tool head. The validity of both the theoretical and numerical models is confirmed by the good agreement between simulation results and data coming from the experiments done within the Tecnospazio facilities.

Finzi, A. E.; Lavagna, M.; Rocchitelli, G.

2004-01-01

270

Solar System Exploration - Probing Below the Surface of Mars  

NSDL National Science Digital Library

As part of this classroom activity, students will record and graph temperature data to learn about the search for water on Mars. Using models of frozen and ice-free "soils" constructed from readily available materials (a list is provided), they will examine (by periodically measuring temperature and graphing the results) how the ice content of the Martian soil affects the rate at which a warm probe will cool. This activity is part of NASA's Solar System Educators Program, a nationwide network of teachers who lead workshops that show other teachers how to successfully incorporate NASA materials and research into their classes. This activity is correlated to National Science Education Standards and NCTM Principles and Standards for School Mathematics.

2004-07-21

271

Radioisotope Power Systems for In-situ Exploration of Titan and Venus  

NASA Technical Reports Server (NTRS)

This viewgraph presentation reviews the timeline for the robotic in situ investigation of Titan and Venus, and the use of radioisotope power systems in this exploration. The atmospheric and surface conditions of both sites are reviewed. The presentation also examines the conceptual design of the Venus Mobile Explorer and the Titan orbiter and in situ explorer. After this the presentation reviews the radioisotope power systems for each of the vehicles, with some explanation of the different requirements based on the vastly different environments that they would be investigating

Balint, Tibor S.

2006-01-01

272

Design space exploration of stochastic System-of-Systems simulations using adaptive sequential experiments  

NASA Astrophysics Data System (ADS)

The complexities of our surrounding environments are becoming increasingly diverse, more integrated, and continuously more difficult to predict and characterize. These modeling complexities are ever more prevalent in System-of-System (SoS) simulations where simulation run times can surpass real-time and are often dictated by stochastic processes and non-continuous emergent behaviors. As the number of connections continue to increase in modeling environments and the number of external noise variables continue to multiply, these SoS simulations can no longer be explored with traditional means without significantly wasted computational resources. This research will discuss the defining features of an SoS and many of the issues plaguing the SoS industry. Then, it will move to a literature review of the concepts currently used to explore design spaces, and finally, it will explore a set of two cascading research areas which will culminate in an adaptive sequential design of experiments for SoS simulations. The first research area will investigate the key features to SoS and the attributes of these SoS which are important to be identified while exploring their simulations. To complete this investigation, first SoS properties are deduced from SoS's relationship to its super-class, complex systems. Second, following this examination, properties are further induced by investigating notional SoS simulations. From these two research avenues it will be discovered these spaces are nonparametric, conditionally variant, non-normally and non-identically distributed. Further, attributes of the output metrics are identified that will increase the likelihood of locating interesting regions of SoS simulations. The knowledge and information gained from this first research focus is used in developing and comparing existing techniques capable of capturing SoS attributes. Several methods from the literature are compared on numerous stochastic mathematical problems and a single notional SoS simulation to determine their relative performance. From this comparison it will be shown that there are currently no methods capable of learning both the mean and variance of these complex spaces. Although the best method will be shown to be the MARS algorithm for generic high dimensional stochastic problems, it will be shown to be inadequate for SoS simulations. Finally, these two research areas will enable the synthesis of an adaptive sequential algorithm capable of exploring stochastic simulations with emphasis on the attributes common to SoS. This final research area will determine strategically where to place points in the design space to improve its predictive capability. The final algorithm will be tested on an identical set of stochastic mathematical problems and the notional SoS simulation from the second research area, but will also include a published high dimensional SoS simulation. The final method will be shown to improve the exploration of stochastic simulations over existing methods by increased global accuracy, the number of simulations required to learn the space, and the computational speed.

Kernstine, Kemp H., Jr.

273

Cradle-to-Grave Logistic Technologies for Exploration Missions  

NASA Technical Reports Server (NTRS)

Human exploration missions under study are very limited by the launch mass capacity of exiting and planned vehicles. The logistical mass of crew items is typically considered separate from the vehicle structure, habitat outfitting, and life support systems. Consequently, crew item logistical mass is typically competing with vehicle systems for mass allocation. NASA is Advanced Exploration Systems (AES) Logistics Reduction and Repurposing (LRR) Project is developing four logistics technologies guided by a systems engineering cradle-to-grave approach to enable used crew items to augment vehicle systems. Specifically, AES LRR is investigating the direct reduction of clothing mass, the repurposing of logistical packaging, the processing of spent crew items to benefit radiation shielding and water recovery, and the conversion of trash to propulsion supply gases. The systematic implementation of these types of technologies will increase launch mass efficiency by enabling items to be used for secondary purposes and improve the habitability of the vehicle as the mission duration increases. This paper provides a description, benefits, and challenges of the four technologies under development and a status of progress at the mid ]point of the three year AES project.

Broyan, James L.; Ewert, Michael K.; Shull, Sarah

2013-01-01

274

Photophysical exploration of fluorescent nanotags  

NASA Astrophysics Data System (ADS)

Fluorescence labeling technique has found many important applications such as medical diagnostics, immunoassays and direct visualization of biological molecules. The main focus of this thesis is to use various techniques to study a number of novel florescence labels named nanotag, with the goal of constructing a fluorescence label that is photostable on both single molecular level and the ensemble level; that is compact in size so that it will not affect the activity of the targeted molecule; and that acts as antenna with strong light-harvesting ability. In the fluorescence spectroscopy, Forster resonance energy transfer (FRET) is a result of the dipole-dipole interaction between a donor fluorophore and an acceptor fluorophore. FRET a useful technique to shift the excitation wavelength to a longer wavelength to minimize the background. In the thesis, the efficiencies of the FRET of a variety of fluorescence labels were explored using different FRET donor-acceptor (D-A) pairs and different D-A ratios aimed to build a superior system where high brightness can be readily achieved and where FRET efficiency has less restriction on the D-A spectral overlap. Also, we are interested in setting up several models to quantitatively simulate the FRET calculation in various designs of nanotags consisting of an array of dyes (multichromophoric array) and in evaluating the suitability of those FRET models. Additionally, this thesis quantitatively evaluates the light harvesting ability of nanotags by examining the antenna effects (AE) defined as the intensity of the nanotag acceptors excited at the donor peak divided by the intensity of the nanotag acceptors upon direct excitation at acceptor absorption peak. Furthermore, we established a model that simulates the AE efficiency in the nanotags. This AE model shows an outstanding agreement with our experimental AE results. Particularly, Chapter 1 introduces the main theories and concepts used in the thesis and the motivations of our experiments. Chapter 2 of the thesis provides the readers with the instrumentation set up and the experimental design. Chapter 3 explores the fluorescence quenching of the DNA-bound dyes using different sized gold nanoparticles as the quencher. Chapter 4 discusses the photophysics of a novel fluorescence label non-covalently loaded with dyes. Chapter 5 discusses the photophysics of the fluorescence labels with covalently bound the dyes.

Liu, Shengpeng

275

ERP system implementation in SMEs: exploring the influences of the SME context  

Microsoft Academic Search

Small and medium-sized enterprises (SMEs) are increasingly implementing enterprise resource planning (ERP) systems. Compared to large enterprises, SMEs differ in a number of inherent characteristics, which are likely to impact the ERP system implementations. The purpose of this study is to explore these influences of the SME context on the ERP system implementation process. SME characteristics are synthesised from relevant

Ondrej Zach; Bjørn Erik Munkvold; Dag Håkon Olsen

2012-01-01

276

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

Microsoft Academic Search

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

Jaime Esper

2005-01-01

277

GSFC Information Systems Technology Developments Supporting the Vision for Space Exploration  

NASA Technical Reports Server (NTRS)

The Vision for Space Exploration will guide NASA's future human and robotic space activities. The broad range of human and robotic missions now being planned will require the development of new system-level capabilities enabled by emerging new technologies. Goddard Space Flight Center is actively supporting the Vision for Space Exploration in a number of program management, engineering and technology areas. This paper provides a brief background on the Vision for Space Exploration and a general overview of potential key Goddard contributions. In particular, this paper focuses on describing relevant GSFC information systems capabilities in architecture development; interoperable command, control and communications; and other applied information systems technology/research activities that are applicable to support the Vision for Space Exploration goals. Current GSFC development efforts and task activities are presented together with future plans.

Hughes, Peter; Dennehy, Cornelius; Mosier, Gary; Smith, Dan; Rykowski, Lisa

2004-01-01

278

Biomorphic Explorers  

NASA Technical Reports Server (NTRS)

This paper presents, in viewgraph form, the first NASA/JPL workshop on Biomorphic Explorers for future missions. The topics include: 1) Biomorphic Explorers: Classification (Based on Mobility and Ambient Environment); 2) Biomorphic Flight Systems: Vision; 3) Biomorphic Explorer: Conceptual Design; 4) Biomorphic Gliders; 5) Summary and Roadmap; 6) Coordinated/Cooperative Exploration Scenario; and 7) Applications. This paper also presents illustrations of the various biomorphic explorers.

Thakoor, Sarita

1999-01-01

279

Crew systems: integrating human and technical subsystems for the exploration of space  

NASA Technical Reports Server (NTRS)

Space exploration missions will require combining human and technical subsystems into overall "crew systems" capable of performing under the rigorous conditions of outer space. This report describes substantive and conceptual relationships among humans, intelligent machines, and communication systems, and explores how these components may be combined to complement and strengthen one another. We identify key research issues in the combination of humans and technology and examine the role of individual differences, group processes, and environmental conditions. We conclude that a crew system is, in effect, a social cyborg, a living system consisting of multiple individuals whose capabilities are extended by advanced technology.

Connors, M. M.; Harrison, A. A.; Summit, J.

1994-01-01

280

Crew systems: integrating human and technical subsystems for the exploration of space.  

PubMed

Space exploration missions will require combining human and technical subsystems into overall "crew systems" capable of performing under the rigorous conditions of outer space. This report describes substantive and conceptual relationships among humans, intelligent machines, and communication systems, and explores how these components may be combined to complement and strengthen one another. We identify key research issues in the combination of humans and technology and examine the role of individual differences, group processes, and environmental conditions. We conclude that a crew system is, in effect, a social cyborg, a living system consisting of multiple individuals whose capabilities are extended by advanced technology. PMID:8060292

Connors, M M; Harrison, A A; Summit, J

1994-07-01

281

Electric Propulsion Concepts Enabled by High Power Systems for Space Exploration  

NASA Technical Reports Server (NTRS)

This paper describes the latest development in electric propulsion systems being planned for the new Space Exploration initiative. Missions to the Moon and Mars will require these new thrusters to deliver the large quantities of supplies that would be needed to support permanent bases on other worlds. The new thrusters are also being used for unmanned exploration missions that will go to the far reaches of the solar system. This paper is intended to give the reader some insight into several electric propulsion concepts their operating principles and capabilities, as well as an overview of some mission applications that would benefit from these propulsion systems, and their accompanying advanced power systems.

Gilland, James; Fiehler, Douglas; Lyons, Valerie

2005-01-01

282

Logistics Reduction Technologies for Exploration Missions  

NASA Technical Reports Server (NTRS)

Human exploration missions under study are very limited by the launch mass capacity of existing and planned vehicles. The logistical mass of crew items is typically considered separate from the vehicle structure, habitat outfitting, and life support systems. Consequently, crew item logistical mass is typically competing with vehicle systems for mass allocation. NASA's Advanced Exploration Systems (AES) Logistics Reduction and Repurposing (LRR) Project is developing five logistics technologies guided by a systems engineering cradle-to-grave approach to enable used crew items to augment vehicle systems. Specifically, AES LRR is investigating the direct reduction of clothing mass, the repurposing of logistical packaging, the use of autonomous logistics management technologies, the processing of spent crew items to benefit radiation shielding and water recovery, and the conversion of trash to propulsion gases. The systematic implementation of these types of technologies will increase launch mass efficiency by enabling items to be used for secondary purposes and improve the habitability of the vehicle as the mission duration increases. This paper provides a description and the challenges of the five technologies under development and the estimated overall mission benefits of each technology.

Broyan, James L., Jr.; Ewert, Michael K.; Fink, Patrick W.

2014-01-01

283

Parallelizing AES on multicores and GPUs  

Microsoft Academic Search

The AES block cipher cryptographic algorithm is widely used and it is resource intensive. An existing sequential open source implementation of the algorithm was parallelized on multi-core microprocessors and GPUs. Performance results are presented.

Julian Ortega; Helmuth Trefftz; Christian Trefftz

2011-01-01

284

Solar system exploration from the Moon: Synoptic and comparative study of bodies in our Planetary system  

NASA Technical Reports Server (NTRS)

An observational approach to Planetary Sciences and exploration from Earth applies to a quite limited number of targets, but most of these are spatially complex, and exhibit variability and evolution on a number of temporal scales which lie within the scope of possible observations. Advancing our understanding of the underlying physics requires the study of interactions between the various elements of such systems, and also requires study of the comparative response of both a given object to various conditions and of comparable objects to similar conditions. These studies are best conducted in 'campaigns', i.e. comprehensive programs combining simultaneous coherent observations of every interacting piece of the puzzle. The requirements include both imaging and spectroscopy over a wide spectral range, from UV to IR. While temporal simultaneity of operation in various modes is a key feature, these observations are also conducted over extended periods of time. The moon is a prime site offering long unbroken observation times and high positional stability, observations at small angular separation from the sun, comparative studies of planet Earth, and valuable technical advantages. A lunar observatory should become a central piece of any coherent set of planetary missions, supplying in-situ explorations with the synoptic and comparative data necessary for proper advance planning, correlative observations during the active exploratory phase, and follow-up studies of the target body or of related objects.

Bruston, P.; Mumma, M. J.

1994-01-01

285

Architecting the Communication and Navigation Networks for NASA's Space Exploration Systems  

NASA Technical Reports Server (NTRS)

NASA is planning a series of short and long duration human and robotic missions to explore the Moon and then Mars. A key objective of the missions is to grow, through a series of launches, a system of systems communication, navigation, and timing infrastructure at minimum cost while providing a network-centric infrastructure that maximizes the exploration capabilities and science return. There is a strong need to use architecting processes in the mission pre-formulation stage to describe the systems, interfaces, and interoperability needed to implement multiple space communication systems that are deployed over time, yet support interoperability with each deployment phase and with 20 years of legacy systems. In this paper we present a process for defining the architecture of the communications, navigation, and networks needed to support future space explorers with the best adaptable and evolable network-centric space exploration infrastructure. The process steps presented are: 1) Architecture decomposition, 2) Defining mission systems and their interfaces, 3) Developing the communication, navigation, networking architecture, and 4) Integrating systems, operational and technical views and viewpoints. We demonstrate the process through the architecture development of the communication network for upcoming NASA space exploration missions.

Bhassin, Kul B.; Putt, Chuck; Hayden, Jeffrey; Tseng, Shirley; Biswas, Abi; Kennedy, Brian; Jennings, Esther H.; Miller, Ron A.; Hudiburg, John; Miller, Dave; Jeffries, Alan; Sartwell, Tom

2007-01-01

286

Analysis of planetary exploration spacesuit systems and evaluation of a modified partial-gravity simulation technique  

NASA Astrophysics Data System (ADS)

Building on prior experience during Apollo, NASA now plans to send humans back to the Moon and then on to Mars as part of its Vision for Space Exploration. An integral component for enabling this plan is the development of advanced spacesuit systems. A planetary exploration spacesuit system consists of an astronaut, a spacesuit, and the associated surface systems designed to enable completion of mission objectives. This thesis addresses all three aspects, beginning with an examination of the effects of locomotion stability in lunar and Mars gravity from a metabolic energy expenditure standpoint. An experiment to determine the effects of stability on running in reduced gravity was performed with a modified vertical offload partial gravity device. Operations scenarios were also developed, along with engineering analysis to understand the forces and moments involved in partial gravity locomotion. Analysis is presented to assess the applicability of terrestrial exploration systems and to adapt them for planetary exploration. Access systems for partial gravity planetary explorations are described that may allow humans in spacesuits to safely access scientifically significant terrain on the Moon and Mars. Contingency scenarios for effective rescue of astronauts from flat and sloped terrain were also analyzed. Conclusions and recommendations are offered regarding the effectiveness of the simulation technique developed. An Earth-based field testing program plan is presented with the intent of including access systems in the lunar surface system architecture requirements early enough to allow synergies in component design.

Chappell, Steven Patrick

287

Exploring information systems outsourcing in U.S. hospital-based health care delivery systems.  

PubMed

The purpose of this study is to explore the factors associated with outsourcing of information systems (IS) in hospital-based health care delivery systems, and to determine if there is a difference in IS outsourcing activity based on the strategic value of the outsourced functions. IS sourcing behavior is conceptualized as a case of vertical integration. A synthesis of strategic management theory (SMT) and transaction cost economics (TCE) serves as the theoretical framework. The sample consists of 1,365 hospital-based health care delivery systems that own 3,452 hospitals operating in 2004. The findings indicate that neither TCE nor SMT predicted outsourcing better than the other did. The findings also suggest that health care delivery system managers may not be considering significant factors when making sourcing decisions, including the relative strategic value of the functions they are outsourcing. It is consistent with previous literature to suggest that the high cost of IS may be the main factor driving the outsourcing decision. PMID:20058531

Diana, Mark L

2009-12-01

288

Moving Towards a Common Ground and Flight Data Systems Architecture for NASA's Exploration Missions  

NASA Technical Reports Server (NTRS)

The National Aeronautics and Space Administration has embarked on an ambitious effort to return man to the moon and then on to Mars. The Exploration Vision requires development of major new space and ground assets and poses challenges well beyond those faced by many of NASA's recent programs. New crewed vehicles must be developed. Compatible supply vehicles, surface mobility modules and robotic exploration capabilities will supplement the manned exploration vehicle. New launch systems will be developed as well as a new ground communications and control infrastructure. The development must take place in a cost-constrained environment and must advance along an aggressive schedule. Common solutions and system interoperability and will be critical to the successful development of the Exploration data systems for this wide variety of flight and ground elements. To this end, NASA has assembled a team of engineers from across the agency to identify the key challenges for Exploration data systems and to establish the most beneficial strategic approach to be followed. Key challenges and the planned NASA approach for flight and ground systems will be discussed in the paper. The described approaches will capitalize on new technologies, and will result in cross-program interoperability between spacecraft and ground systems, from multiple suppliers and agencies.

Rader. Steve; Kearney, Mike; McVittie, Thom; Smith, Dan

2006-01-01

289

The Role of Lunar Development in Human Exploration of the Solar System  

NASA Technical Reports Server (NTRS)

Human exploration of the solar system can be said to have begun with the Apollo landings on the Moon. The Apollo Project was publicly funded with the narrow technical objective of landing human beings on the Moon. The transportation and life support systems were specialized technical designs, developed in a project management environment tailored to that objective. Most scenarios for future human exploration assume a similar long-term commitment of public funds to a narrowly focused project managed by a large, monolithic organization. Advocates of human exploration of space have not yet been successful in generating the political momentum required to initiate such a project to go to the Moon or to Mars. Alternative scenarios of exploration may relax some or all of the parameters of organizational complexity, great expense, narrow technical focus, required public funding, and control by a single organization. Development of the Moon using private investment is quite possibly a necessary condition for alternative scenarios to succeed.

Mendell, Wendell W.

1999-01-01

290

OEXP exploration studies technical report. Volume 3: Special reports, studies, and indepth systems assessments  

NASA Technical Reports Server (NTRS)

The Office of Exploration (OEXP) at NASA has been tasked with defining and recommending alternatives for an early 1990's national decision on a focused program of manned exploration of the Solar System. The Mission analysis and System Engineering (MASE) group, which is managed by the Exploration Studies Office at the Johnson Space Center, is responsible for coordinating the technical studies necessary for accomplishing such a task. This technical report, produced by the MASE, describes the process used to conduct exploration studies and discusses the mission developed in a case study approach. The four case studies developed in FY88 include: (1) a manned expedition to PHOBOS; (2) a manned expedition to MARS; (3) a lunar surface observatory; and a lunar outpost to early Mars evolution. The final outcome of this effort is a set of programmatic and technical conclusions and recommendations for the following year's work.

Roberts, Barney B.; Bland, Dan

1988-01-01

291

Doing more with less - The new way of exploring the solar system  

NASA Technical Reports Server (NTRS)

Exploration of the solar system is considered in the light of existing economic factors and scientific priorities, and a general blueprint for an exploration strategy is set forth. Attention is given to mission costs, typical schedules, and the scientific findings of typical projects which create the need for collaboration and diversification in mission development. The combined technologies and cooperative efforts of several small organizations can lead to missions with short schedules and low costs.

Ridenoure, Rex

1992-01-01

292

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

NASA Technical Reports Server (NTRS)

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.

1991-01-01

293

Advances in Robotic, Human, and Autonomous Systems for Missions of Space Exploration  

NASA Technical Reports Server (NTRS)

Space exploration missions are evolving toward more complex architectures involving more capable robotic systems, new levels of human and robotic interaction, and increasingly autonomous systems. How this evolving mix of advanced capabilities will be utilized in the design of new missions is a subject of much current interest. Cost and risk constraints also play a key role in the development of new missions, resulting in a complex interplay of a broad range of factors in the mission development and planning of new missions. This paper will discuss how human, robotic, and autonomous systems could be used in advanced space exploration missions. In particular, a recently completed survey of the state of the art and the potential future of robotic systems, as well as new experiments utilizing human and robotic approaches will be described. Finally, there will be a discussion of how best to utilize these various approaches for meeting space exploration goals.

Gross, Anthony R.; Briggs, Geoffrey A.; Glass, Brian J.; Pedersen, Liam; Kortenkamp, David M.; Wettergreen, David S.; Nourbakhsh, I.; Clancy, Daniel J.; Zornetzer, Steven (Technical Monitor)

2002-01-01

294

Integrated Solar System Exploration Education and Public Outreach: Theme, Products and Activities  

NASA Technical Reports Server (NTRS)

NASA's Solar System Exploration Program is entering an unprecedented period of exploration and discovery. Its goal is to understand the origin and evolution of the solar system and life within it. SSE missions are operating or in development to study the far reaches of our solar system and beyond. These missions proceed in sequence for each body from reconnaissance flybys through orbiters and landers or rovers to sample returns. SSE research programs develop new instruments, analyze mission data or returned samples, and provide experimental or theoretical models to aid in interpretation.

Lowes, Leslie; Lindstrom, Marilyn; Stockman, Stephanie; Scalice, Daniela; Allen, Jaclyn; Tobola, Kay; Klug, Sheri; Harmon, Art

2004-01-01

295

Field Testing of the Mars Exploration Rovers Descent Image Motion Estimation System  

Microsoft Academic Search

Abstract ? The Mars Exploration Rover (MER) Descent Image Motion Estimation System (DIMES) is the first autonomous machine vision system used to safely land a robotics payload on another planet. DIMES consists of a descent camera and an algorithm for estimating horizontal velocity using image, inertial and altitude measurements. Before DIMES was accepted by MER for inclusion in the mission,

Andrew Edie Johnson; Reg G. Willson; Jay Goguen; James Alexander; David Meller

2005-01-01

296

Stepping into futures: exploring the potential of interactive media for participatory scenarios on social ecological systems  

Microsoft Academic Search

In this paper, we present a strategy for the development of interactive media scenarios to help communicate uncertainties and complexities in coupled human and natural systems. Insights arising from Complex Adaptive Systems theory advocate the need for more adaptive perspectives on natural resources management. For the collaborative exploration of future complexities and uncertainties, participatory scenario development has proven to be

J. M. Vervoort; K. Kok; Lammeren van R. J. A; A. Veldkamp

2010-01-01

297

Understanding the Chena Hot Springs, Alaska, geothermal system using temperature and pressure data from exploration boreholes  

Microsoft Academic Search

Chena Hot Springs is a small, moderate temperature, deep circulating geothermal system, apparently typical of those associated to hot springs of interior Alaska. Multi-stage drilling was used in some exploration boreholes and was found to be useful for understanding subsurface flow characteristics and developing a conceptual model of the system. The results illustrate how temperature profiles illuminate varying pressure versus

Kamil Erkan; Gwen Holdmann; Walter Benoit; David Blackwell

2008-01-01

298

A Systematic Approach to Exploring Embedded System Architectures at Multiple Abstraction Levels  

Microsoft Academic Search

The sheer complexity of today's embedded systems forces designers to start with modeling and simulating system components and their interactions in the very early design stages. It is therefore imperative to have good tools for exploring a wide range of design choices, especially during the early design stages, where the design space is at its largest. This paper presents an

Andy D. Pimentel; Cagkan Erbas; Simon Polstra

2006-01-01

299

"Storms of crustal stress" and AE earthquake precursors  

NASA Astrophysics Data System (ADS)

Acoustic emission (AE) displays violent paroxysms preceding strong earthquakes, observed within some large area (several hundred kilometres wide) around the epicentre. We call them "storms of crustal stress" or, briefly "crustal storms". A few case histories are discussed, all dealing with the Italian peninsula, and with the different behaviour shown by the AE records in the Cephalonia island (Greece), which is characterized by a different tectonic setting. AE is an effective tool for diagnosing the state of some wide slab of the Earth's crust, and for monitoring its evolution, by means of AE of different frequencies. The same effect ought to be detected being time-delayed, when referring to progressively lower frequencies. This results to be an effective check for validating the physical interpretation. Unlike a seismic event, which involves a much limited focal volume and therefore affects a restricted area on the Earth's surface, a "crustal storm" typically involves some large slab of lithosphere and crust. In general, it cannot be easily reckoned to any specific seismic event. An earthquake responds to strictly local rheological features of the crust, which are eventually activated, and become crucial, on the occasion of a "crustal storm". A "crustal storm" lasts typically few years, eventually involving several destructive earthquakes that hit at different times, at different sites, within that given lithospheric slab. Concerning the case histories that are here discussed, the lithospheric slab is identified with the Italian peninsula. During 1996-1997 a "crustal storm" was on, maybe elapsing until 2002 (we lack information for the period 1998-2001). Then, a quiet period occurred from 2002 until 26 May 2008, when a new "crustal storm" started, and by the end of 2009 it is still on. During the 1996-1997 "storm" two strong earthquakes occurred (Potenza and Colfiorito) - and (maybe) in 2002 also the Molise earthquake can be reckoned to this "storm". During the "storm", started in 2008, the l'Aquila earthquake occurred. Additional logical analysis envisages the possibility of distinguishing some kind of "elementary" constituents of a "crustal storm", which can be briefly called "crustal substorms". The concept of "storm" and "substorm" is a common logical aspect, which is shared by several phenomena, depending on their common intrinsic and primary logical properties that can be called lognormality and fractality. Compared to a "crustal storm", a "crustal substorm" is likely to be reckoned to some specific seismic event. Owing to brevity purposes, however, the discussion of "substorms" is given elsewhere. AE is an effective tool for monitoring these phenomena, and other processes that are ongoing within the crust. Eventually they result to be precursors of some more or less violent earthquake. It should be stressed, however, that the target of AE monitoring is diagnosing the Earth's crust. In contrast, earthquake prediction implies a much different perspective, which makes sense only by means of more detailed multiparametric monitoring. An AE array can provide real physical information only about the processes that are objectively ongoing inside different and contiguous large slabs of the crust. The purpose is to monitor the stress propagation that crosses different regions, in order to envisage where and when it can eventually trigger a catastrophe of the system. The conclusion is that continental - or planetary - scale arrays of AE monitoring stations, which record a few different AE frequencies, appear to be the likely first step for diagnosing the evolution of local structures preceding an earthquake. On the other hand, as it is well known, the magnitude of the shock is to be related to the elastic energy stored in the focal volume, rather than to the trigger that starts it.

Gregori, G. P.; Poscolieri, M.; Paparo, G.; de Simone, S.; Rafanelli, C.; Ventrice, G.

2010-02-01

300

An Optimized S-Box Circuit Architecture for Low Power AES Design  

Microsoft Academic Search

Reducing the power consumption of AES circuits is a critical problem when the circuits are used in low power embedded systems.\\u000a We found the S-Boxes consume much of the total AES circuit power and the power for an S-Box is mostly determined by the number\\u000a of dynamic hazards. In this paper, we propose a low-power S-Box circuit architecture: a multi-stage

Sumio Morioka; Akashi Satoh

2002-01-01

301

PR3-722, Evaluation of the capabilities of advanced acoustic emissions (AE) monitoring of buried gas transmission pipelines  

Microsoft Academic Search

The Pipeline Authority (TPA) conducted an in-service inspection using acoustic emission (AE) monitoring to ensure the integrity of their line. The objectives of the tests were: to determine if any critical stress corrosion cracks were present, to estimate their locations, and to evaluate the effectiveness of commercial AE systems for inspecting in-service pipelines. Battelle served as a consultant. The test

Stulen

1989-01-01

302

Atmosphere Explorer set for launch  

NASA Technical Reports Server (NTRS)

The Atmosphere Explorer-D (Explorer-54) is described which will explore in detail an area of the earth's outer atmosphere where important energy transfer, atomic and molecular processes, and chemical reactions occur that are critical to the heat balance of the atmosphere. Data are presented on the mission facts, launch vehicle operations, AE-D/Delta flight events, spacecraft description, scientific instruments, tracking, and data acquisition.

1975-01-01

303

Environmental Controls and Life Support System Design for a Space Exploration Vehicle  

NASA Technical Reports Server (NTRS)

Engineers at Johnson Space Center (JSC) are developing an Environmental Control and Life Support System (ECLSS) design for the Space Exploration Vehicle (SEV). The SEV will aid to expand the human exploration envelope for Geostationary Transfer Orbit (GEO), Near Earth Object (NEO), or planetary missions by using pressurized surface exploration vehicles. The SEV, formerly known as the Lunar Electric Rover (LER), will be an evolutionary design starting as a ground test prototype where technologies for various systems will be tested and evolve into a flight vehicle. This paper will discuss the current SEV ECLSS design, any work contributed toward the development of the ECLSS design, and the plan to advance the ECLSS design based on the SEV vehicle and system needs.

Stambaugh, Imelda C.; Rodriguez, Branelle; Vonau, Walt, Jr.; Borrego, Melissa

2012-01-01

304

Environmental Controls and Life Support System (ECLSS) Design for a Space Exploration Vehicle (SEV)  

NASA Technical Reports Server (NTRS)

Engineers at Johnson Space Center (JSC) are developing an Environmental Control and Life Support System (ECLSS) design for the Space Exploration Vehicle (SEV). The SEV will aid to expand the human exploration envelope for Geostationary Transfer Orbit (GEO), Near Earth Object (NEO), or planetary missions by using pressurized surface exploration vehicles. The SEV, formerly known as the Lunar Electric Rover (LER), will be an evolutionary design starting as a ground test prototype where technologies for various systems will be tested and evolve into a flight vehicle. This paper will discuss the current SEV ECLSS design, any work contributed toward the development of the ECLSS design, and the plan to advance the ECLSS design based on the SEV vehicle and system needs.

Stambaugh, Imelda; Sankaran, Subra

2010-01-01

305

Marine Engineering Geological Exploration Information System (MEGEIS): A GIS-based application to marine resources exploitation  

NASA Astrophysics Data System (ADS)

Based on the ArcGIS geographic information system and the ORACLE database management system, this paper reports our studies on the technology of Marine Engineering Geological Exploration Information System (MEGEIS). By analyzing system structure, designing function modules and discussing data management, this paper systematically proposes a framework of technology to integrate, manage, and analyze the seabed information comprehensively. Then, the technology is applied to the design and development of the Bohai Sea Oilfield Paradigm Area Information System. The system can not only meet the practical demands of marine resources exploration and exploitation in the Bohai Sea oilfield, but also serve as a preparatory work in theory and technology for the realization of the ‘Digital Seabed’.

Su, Tianyun; Liu, Baohua; Zhai, Shikui; Liang, Ruicai; Zheng, Yanpeng

2007-07-01

306

Near-Earth Objects: Targets for Future Human Exploration, Solar System Science, and Planetary Defense  

NASA Technical Reports Server (NTRS)

Human exploration of near-Earth objects (NEOs) beginning circa 2025 - 2030 is one of the stated objectives of U.S. National Space Policy. Piloted missions to these bodies would further development of deep space mission systems and technologies, obtain better understanding of the origin and evolution of our Solar System, and support research for asteroid deflection and hazard mitigation strategies. This presentation will discuss some of the physical characteristics of NEOs and review some of the current plans for NEO research and exploration from both a human and robotic mission perspective.

Abell, Paul A.

2011-01-01

307

Exploring the use of death certificates as a component of an occupational health surveillance system.  

PubMed Central

An effort has been made to explore a case-finding surveillance system for occupationally-related disease using death records. A sentinel health event, here lung cancer in young males, was selected to seek unusual associations with occupations as listed on the death records. Fishermen appeared to be over-represented and population studies cited suggest lung cancer in this occupation deserves further exploration. Further efforts of this type could test the usefulness of an occupational health surveillance system based on the death certificate.

Frazier, T M; Wegman, D H

1979-01-01

308

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

309

Advanced AE Techniques in Composite Materials Research  

NASA Technical Reports Server (NTRS)

Advanced, waveform based acoustic emission (AE) techniques have been successfully used to evaluate damage mechanisms in laboratory testing of composite coupons. An example is presented in which the initiation of transverse matrix cracking was monitored. In these tests, broad band, high fidelity acoustic sensors were used to detect signals which were then digitized and stored for analysis. Analysis techniques were based on plate mode wave propagation characteristics. This approach, more recently referred to as Modal AE, provides an enhanced capability to discriminate and eliminate noise signals from those generated by damage mechanisms. This technique also allows much more precise source location than conventional, threshold crossing arrival time determination techniques. To apply Modal AE concepts to the interpretation of AE on larger composite specimens or structures, the effects of modal wave propagation over larger distances and through structural complexities must be well characterized and understood. To demonstrate these effects, measurements of the far field, peak amplitude attenuation of the extensional and flexural plate mode components of broad band simulated AE signals in large composite panels are discussed. These measurements demonstrated that the flexural mode attenuation is dominated by dispersion effects. Thus, it is significantly affected by the thickness of the composite plate. Furthermore, the flexural mode attenuation can be significantly larger than that of the extensional mode even though its peak amplitude consists of much lower frequency components.

Prosser, William H.

1996-01-01

310

High-temperature nuclear closed Brayton cycle power conversion system for the space exploration initiative  

NASA Astrophysics Data System (ADS)

The Space Exploration Initiative (SEI) has stated goals of colonizing the moon and conducting manned exploration of the planet Mars. Unlike previous ventures into space, both manned and unmanned, large quantities of electrical power will be required to provide the energy for lunar base sustenance and for highly efficient propulsion systems for the long trip to mars and return. Further, the requirement for electrical power of several megawatts will necessitate the use of nuclear reactor driven power conversion systems. This paper discusses a particle bed reactor closed Brayton cycle space power system that uses advanced materials technology to achieve a high-temperature, low-specific-weight modular system capable of providing the requisite electrical power for both a lunar base and a Mars flight vehicle propulsion system.

Brandes, Donald J.

1991-01-01

311

High-temperature nuclear closed Brayton cycle power conversion system for the Space Exploration Initiative  

NASA Astrophysics Data System (ADS)

The Space Exploration Initiative has stated goals of colonizing the moon and conducting manned exploration of the planet Mars. Unlike previous ventures into space, both manned and unmanned, large quantities of electrical power will be required to provide the energy for lunar base sustenance and for highly efficient propulsion systems for the long trip to Mars and return. Further, the requirement for electrical power of several megawatts will necessitate the use of nuclear reactor driven power conversion systems. This paper discusses a particle bed reactor closed Brayton cycle space power system that uses advanced materials technology to achieve a high-temperature, low-specific-weight modular system capable of providing the requisite electrical power for both a lunar base and a Mars flight vehicle propulsion system.

Brandes, Donald J.

312

Using C to build a satellite scheduling expert system: Examples from the Explorer Platform planning system  

NASA Technical Reports Server (NTRS)

A C-based artificial intelligence (AI) development effort which is based on a software tools approach is discussed with emphasis on reusability and maintainability of code. The discussion starts with simple examples of how list processing can easily be implemented in C and then proceeds to the implementations of frames and objects which use dynamic memory allocation. The implementation of procedures which use depth first search, constraint propagation, context switching, and blackboard-like simulation environment are described. Techniques for managing the complexity of C-based AI software are noted, especially the object-oriented techniques of data encapsulation and incremental development. Finally, all these concepts are put together by describing the components of planning software called the Planning And Resource Reasoning (PARR) Shell. This shell was successfully utilized for scheduling services of the Tracking and Data Relay Satellite System for the Earth Radiation Budget Satellite since May of 1987 and will be used for operations scheduling of the Explorer Platform in Nov. of 1991.

Mclean, David R.; Tuchman, Alan; Potter, William J.

1991-01-01

313

Operation and performance of the mars exploration rover imaging system on the martian surface  

USGS Publications Warehouse

The Imaging System on the Mars Exploration Rovers has successfully operated on the surface of Mars for over one Earth year. The acquisition of hundreds of panoramas and tens of thousands of stereo pairs has enabled the rovers to explore Mars at a level of detail unprecedented in the history of space exploration. In addition to providing scientific value, the images also play a key role in the daily tactical operation of the rovers. The mobile nature of the MER surface mission requires extensive use of the imaging system for traverse planning, rover localization, remote sensing instrument targeting, and robotic arm placement. Each of these activity types requires a different set of data compression rates, surface coverage, and image acquisition strategies. An overview of the surface imaging activities is provided, along with a summary of the image data acquired to date. ?? 2005 IEEE.

Maki, J. N.; Litwin, T.; Schwochert, M.; Herkenhoff, K.

2005-01-01

314

Design, development and testing of the x-ray timing explorer High Gain Antenna System  

NASA Technical Reports Server (NTRS)

The High Gain Antenna System (HGAS), consisting of two High Gain Antenna Deployment Systems (HGADS) and two Antenna Pointing Systems (APS), is used to position two High Gain Antennas (HGA) on the X-Ray Timing Explorer (XTE). A similar APS will be used on the upcoming Tropical Rainfall Measuring Mission (TRMM). Both XTE and TRMM are NASA in-house satellites. The salient features of the system include the two-axis gimbal and control electronics of the APS and the spring deployment and latch/release mechanisms of the HGADS. This paper describes some of the challenges faced in the design and testing of this system and their resolutions.

Lecha, Javier; Woods, Claudia; Phan, Minh

1995-01-01

315

Exploration Platform in the Earth-Moon Libration System Based on ISS  

NASA Technical Reports Server (NTRS)

International Space Station (ISS) industry partners have been working for the past two years on concepts using ISS development methods and residual assets to support a broad range of exploration missions. These concepts have matured along with planning details for NASA's Space Launch System (SLS) and Multi-Purpose Crew Vehicle (MPCV) to allow serious consideration for a platform located in the Earth-Moon Libration (EML) system. This platform would provide a flexible basis for future exploration missions and would significantly reduce costs because it will enable re-use of expensive spacecraft and reduce the total number of launches needed to accomplish these missions. ISS provides a robust set of methods which can be used to test systems and capabilities needed for missions to the Moon, Mars, asteroids and other potential destinations. We will show how ISS can be used to reduce risk and improve operational flexibility for missions beyond low earth orbit through the development of a new Exploration Platform based in the EML system. The benefits of using the EML system as a gateway will be presented along with additional details of a lunar exploration mission concept. International cooperation is a critical enabler and ISS has already demonstrated successful management of a large multi-national technical endeavor. We will show how technology developed for ISS can be evolved and adapted to the new exploration challenge. 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. Finally, we will describe how the EML Platform could be built and deployed and how International access for crew and cargo could be provided.

Raftery, Michael; Derechin, Alexander

2012-01-01

316

Spacecraft/rover hybrids for the exploration of small Solar System bodies  

NASA Astrophysics Data System (ADS)

In this paper we present a mission architecture for the systematic and affordable in-situ exploration of small Solar System bodies (such as asteroids, comets, and Martian moons). At a general level, a mother spacecraft would deploy on the surface of a small body one, or several, spacecraft/rover hybrids, which are small (<; 5 kg, ? 15 Watts), multi-faceted robots enclosing three mutually orthogonal flywheels and surrounded by external spikes (in particular, there is no external propulsion). By accelerating/decelerating the flywheels and by exploiting the low gravity environment, the hybrids would be capable of performing both long excursions (by hopping) and short traverses to specific locations (through a sequence of controlled “ tumbles” ). Their control would rely on synergistic operations with the mother spacecraft (where most of hybrids perception and localization functionalities would be hosted), which would make the platforms minimalistic and in turn the entire mission architecture affordable. Specifically, in the first part of the paper we present preliminary models and laboratory experiments for the hybrids, first-order estimates for critical subsystems, and a preliminary study for synergistic mission operations. In the second part, we tailor our mission architecture to the exploration of Mars' moon Phobos. The mission aims at exploring Phobos' Stickney crater, whose spectral similarities with C-type asteroids and variety of terrain properties make it a particularly interesting exploration target to address both high-priority science for the Martian system and strategic knowledge gaps for the future human exploration of Mars.

Pavone, M.; Castillo-Rogez, J. C.; Nesnas, I. A. D.; Hoffman, J. A.; Strange, N. J.

317

Artificial Gravity as a Multi-System Countermeasure for Exploration Class Space Flight Missions  

NASA Technical Reports Server (NTRS)

NASA's vision for space exploration includes missions of unprecedented distance and duration. However, during 30 years of human space flight experience, including numerous long-duration missions, research has not produced any single countermeasure or combination of countermeasures that is completely effective. Current countermeasures do not fully protect crews in low-Earth orbit, and certainly will not be appropriate for crews journeying to Mars and back over a three-year period. The urgency for exploration-class countermeasures is compounded by continued technical and scientific successes that make exploration class missions increasingly attractive. The critical and possibly fatal problems of bone loss, cardiovascular deconditioning, muscle weakening, neurovestibular disturbance, space anemia, and immune compromise may be alleviated by the appropriate application of artificial gravity (AG). However, despite a manifest need for new countermeasure approaches, concepts for applying AG as a countermeasure have not developed apace. To explore the utility of AG as a multi-system countermeasure during long-duration, exploration-class space flight, eighty-three members of the international space life science and space flight community met earlier this year. They concluded unanimously that the potential of AG as a multi-system countermeasure is indeed worth pursuing, and that the requisite AG research needs to be supported more systematically by NASA. This presentation will review the issues discussed and recommendations made.

Paloski, William H.; Dawson, David L. (Technical Monitor)

2000-01-01

318

A Mössbauer investigation of iron-rich terrestrial hydrothermal vent systems: Lessons for Mars exploration  

Microsoft Academic Search

Hydrothermal spring systems may well have been present on early Mars and could have served as a habitat for primitive life. The integrated instrument suite of the Athena Rover has, as a component on the robotic arm, a Mössbauer spectrometer. In the context of future Mars exploration we present results of Mössbauer analysis of a suite of samples from an

Manson L. Wade; David G. Agresti; Thomas J. Wdowiak; Lawrence P. Armendarez; Jack D. Farmer

1999-01-01

319

diva: a visualization system for exploring document databases for technology forecasting  

Microsoft Academic Search

Database Information Visualization and Analysis system (diva) is a computer program that helps perform bibliometric analysis of collections of scientific literature and patents for technology forecasting. Documents, drawn from the technological field of interest, are visualized as clusters on a two dimensional map, permitting exploration of the relationships among the documents and document clusters and also permitting derivation of summary

Steven Morris; Camille DeYong; Zheng Wu; Sinan Salman; Dagmawi Yemenu

2002-01-01

320

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

321

Epilogue: The Origins of Life in the Solar System and Future Exploration  

Microsoft Academic Search

The broad investigation of life in the universe must address its long-term survival (the primary focus of this book) and also its origins. Studies of survival address the evolution of the planetary environment, its habitability, the adaptability of living systems to changing conditions and possibly co-evolution of life with its host planet. Studies of origins explore the conditions necessary for

Philippe Lognonne; David Des Marais; François Raulin; Kathryn Fishbaugh

2007-01-01

322

Epilogue: The Origins of Life in the Solar System and Future Exploration  

Microsoft Academic Search

The broad investigation of life in the universe must address its long-term survival (the primary focus of this book) and also its origins. Studies of survival address the evolution of the planetary environment, its habitability, the adaptability of living systems to changing conditions and possibly co-evolution of life with its host planet. Studies of origins explore the conditions necessary for

Philippe Lognonne; David Des Marais; François Raulin; Kathryn Fishbaugh

323

Optical and microwave communications system conceptual design for a realistic interstellar explorer  

Microsoft Academic Search

The concept of a realistic interstellar explorer has been addressed by the Johns Hopkins University Applied Physics Laboratory (JHU\\/APL) with support from the NASA Institute for Advanced Concepts (NIAC). This paper discusses the requirements, conceptual design and technology issues associated with the optical and RF communications systems envisioned for this mission, in which the spacecraft has a projected range of

B. G. Boone; R. S. Bokulic; G. B. Andrewsa; R. L. McNutt

324

JUICE (JUpiter ICy moon Explorer): a European-led mission to the Jupiter system  

NASA Astrophysics Data System (ADS)

The former ESA-NASA EJSM-Laplace mission is being reformulated by ESA as a European-led single spacecraft mission to the Jovian system. The concept has been recently renamed JUICE (JUpiter ICy moon Explorer). The new mission is based on the design of the Jupiter Ganymede Orbiter (JGO) - the ESA flight element of EJSM-Laplace.

Dougherty, M. K.; Grasset, O.; Bunce, E.; Coustenis, A.; Titov, D. V.; Erd, C.; Blanc, M.; Coates, A. J.; Coradini, A.; Drossart, P.; Fletcher, L.; Hussmann, H.; Jaumann, R.; Krupp, N.; Prieto-Ballesteros, O.; Tortora, P.; Tosi, F.; van Hoolst, T.; Lebreton, J.-P.

2011-10-01

325

Reliability and Availability Analysis for the JPL Remote Exploration and Experimentation System  

Microsoft Academic Search

The NASA Remote Exploration and Experimentation (REE) Project, managed by the Jet Propulsion Laboratory, has the vision of bringing commercial supercomputing tech- nology into space, in a form which meets the demanding en- vironmental requirements, to enable a new class of science investigation and discovery. Dependability goals of the REE system are 99% reliability over 5 years and 99% avail-

Dong Chen; Selvamuthu Dharmaraja; Dongyan Chen; Lei Li; Kishor S. Trivedi; Raphael R. Some; Allen P. Nikora

2002-01-01

326

Bioinspired engineering of exploration systems for NASA and DoD: from bees to BEES  

NASA Technical Reports Server (NTRS)

The intent of Bio-inspired Engineering of Exploration Systems (BEES) is to distill the principles found in successful, nature-tested mechanisms of specific crucial functions that are hard to accomplish by conventional methods, but accomplished rather deftly in nature by biological organisms.

Thakoor, S.; Zornetzer, S.; Hine, B.; Chahl, J.; Werblin, F.; Srinivasan, M. V.; Young, L.

2003-01-01

327

Teachers, Narrative Identity and Ability Constructs: Exploring Dissonance and Consensus in Contrasting School Systems  

ERIC Educational Resources Information Center

An exploration of the significance of ability beliefs in four case study schools in contrasting systems (independent and state comprehensives) provides a foundation for this paper. Through four delimited case studies using observations, semi-structured interviews, telephone interviews and multiple perspectives, rich data emerged. Subsequently,…

Hamilton, Lorna Christine

2010-01-01

328

Human support issues and systems for the space exploration initiative: Results from Project Outreach  

NASA Technical Reports Server (NTRS)

The analyses and evaluations of the Human Support panel are discussed. The Human Support panel is one of eight panels created by RAND to screen and analyze submissions to the Space Exploration Initiative (SEI) Outreach Program. Submissions to the Human Support panel were in the following areas: radiation protection; microgravity; life support systems; medical care; and human factors (behavior and performance).

Aroesty, J.; Zimmerman, R.; Logan, J.

1991-01-01

329

The Explorer platform planning system: An application of a resource reasoning planning shell  

NASA Astrophysics Data System (ADS)

The Explorer Platform Planning System (EPPS) designed to provide tools which allow mission planners to schedule the platform activities and resource utilization of each mission is described. In order to support scheduling for different missions, EPPS tools are designed so that the mission specific reconfiguration process can be done with minimum effort and disruption. The planning and scheduling tools which support EPPS are described.

McLean, David R.; Page, Brenda J.; Potter, William J.

1990-10-01

330

In-Flight Propulsion System Characterization for Both Mars Exploration Rover Spacecraft  

Microsoft Academic Search

Two Mars Exploration Rover spacecraft were dispensed to red planet in 2003, culminating in a phenomenally successful prime science mission. Twin cruise stage propulsion systems were developed in record time, largely through heritage with Mars Pathfinder. As expected, consumable usage was minimal during the short seven-month cruise for both spacecraft. Propellant usage models based on pressure and temperature agreed with

Todd J. Barbe; Frank Q. Picha

331

Multiple Independent Introductions of HIV-1 CRF01_AE Identified in China: What Are the Implications for Prevention?  

PubMed Central

Background HIV-1 CRF01_AE accounts for an important fraction of HIV infections in Asia including China, but little is known about the phylogenetic and evolutionary history of this CRF (circulating recombinant form). In the current study, we collected a large number of 1,957 CRF01_AE gag p17 sequences with known sampling year (1990-2010) from 5 global regions representing 15 countries to better understand the phylogenetic relationships and epidemic history of CRF01_AE strains in China. Methodology/Principal Findings CRF01_AE gag p17 sequences were retrieved from public databases to explore phylogenetic relationships and phylogeographic dynamics of CRF01_AE in Asia by using maximum-likelihood phylogenetics and Bayesian coalescent-based analyses. We found close phylogenetic relationships between sequences from Thailand, Vietnam and China. Moreover, at least 5 independent introductions and 5 independent autochthonous clades of CRF01_AE, which descended from Thailand or Vietnam were identified in China from 1991 through 2003. Conclusion/Significance The current study not only defines the migration of CRF01_AE clades to/in Asia, but also demonstrates the criticalness of identifying the circulating strains in the population for the development of vaccine and microbicides.

Zhang, Xiaoyan; Xu, Jianqing

2013-01-01

332

State Space Exploration of Object-Based Systems Using Equivalence Reduction and the Sweepline Method  

Microsoft Academic Search

\\u000a Object-based systems present particular challenges for state space exploration. Objects can be dynamically created and discarded,\\u000a and can be referenced via object identifiers. Consistent relabelling of object identifiers in a state leads to a state that\\u000a is superficially different but behaviourally equivalent to the original. Similarly, object-based systems can include garbage\\u000a which has no effect on subsequent behaviour but which

Charles A. Lakos; Lars Michael Kristensen

2005-01-01

333

Destination Deimos: A Design Reference Architecture for Initial Human Exploration of the Mars System  

NASA Technical Reports Server (NTRS)

The two biggest challenges to successful human operations in interplanetary space are flight dynamics, constrained by the cold hard physics of the rocket equation, and bioastronautics, the psychophysiological realities of human adaptation, or lack thereof, to the deep space environment. Without substantial innovation in project/mission architecture and vehicle design, human exploration of the Mars system could be problematic for decades. Although a human landing on Mars is inevitable, humans-in-the-loop telerobotic exploration from the outer Martian moon Deimos is the best way to begin. Precursor robotic missions for reconnaissance and local site preparation will be required.

Logan, James S.; Adamo, D. R.

2011-01-01

334

Exploring the Edge of Our Solar System: IBEX Mission (Poster Back)  

NSDL National Science Digital Library

This poster outlines the major mission highlights of the Interstellar Boundary Explorer (IBEX) mission, a Small Explorer Earth-orbiting spacecraft that is designed to map the distant boundary between the solar wind from our Sun and the interstellar medium. This poster supports a full length planetarium show about the IBEX mission and the boundary of the Solar System. Each short activity/product helps to build awareness and engagement in the science and engineering aspects of the mission that are reinforced as visitors choose to participate in more activities, including viewing the Show and mission website.

2010-12-28

335

Cytosolic H+ microdomain developed around AE1 during AE1-mediated Cl?/HCO3? exchange  

PubMed Central

Abstract Microdomains, regions of discontinuous cytosolic solute concentration enhanced by rapid solute transport and slow diffusion rates, have many cellular roles. pH-regulatory membrane transporters, like the Cl?/HCO3? exchanger AE1, could develop H+ microdomains since AE1 has a rapid transport rate and cytosolic H+ diffusion is slow. We examined whether the pH environment surrounding AE1 differs from other cellular locations. As AE1 drives Cl?/HCO3? exchange, differences in pH, near and remote from AE1, were monitored by confocal microscopy using two pH-sensitive fluorescent proteins: deGFP4 (GFP) and mNectarine (mNect). Plasma membrane (PM) pH (defined as ?1 ?m region around the cell periphery) was monitored by GFP fused to AE1 (GFP.AE1), and mNect fused to an inactive mutant of the Na+-coupled nucleoside co-transporter, hCNT3 (mNect.hCNT3). GFP.AE1 to mNect.hCNT3 distance was varied by co-expression of different amounts of the two proteins in HEK293 cells. As the GFP.AE1–mNect.hCNT3 distance increased, mNect.hCNT3 detected the Cl?/HCO3? exchange-associated cytosolic pH change with a time delay and reduced rate of pH change compared to GFP.AE1. We found that a H+ microdomain 0.3 ?m in diameter forms around GFP.AE1 during physiological HCO3? transport. Carbonic anhydrase isoform II inhibition prevented H+ microdomain formation. We also measured the rate of H+ movement from PM GFP.AE1 to endoplasmic reticulum (ER), using mNect fused to the cytosolic face of ER-resident calnexin (CNX.mNect). The rate of H+ diffusion through cytosol was 60-fold faster than along the cytosolic surface of the plasma membrane. The pH environment surrounding pH regulatory transport proteins may differ as a result of H+ microdomain formation, which will affect nearby pH-sensitive processes.

Johnson, Danielle E; Casey, Joseph R

2011-01-01

336

A Titan Explorer Mission Utilizing Solar Electric Propulsion and Chemical Propulsion Systems  

NASA Technical Reports Server (NTRS)

Mission and Systems analyses were performed for a Titan Explorer Mission scenario utilizing medium class launch vehicles, solar electric propulsion system (SEPS) for primary interplanetary propulsion, and chemical propulsion for capture at Titan. An examination of a range of system factors was performed to determine their affect on the payload delivery capability to Titan. The effect of varying the launch vehicle, solar array power, associated number of SEPS thrusters, chemical propellant combinations, tank liner thickness, and tank composite overwrap stress factor was investigated. This paper provides a parametric survey of the aforementioned set of system factors, delineating their affect on Titan payload delivery, as well as discussing aspects of planetary capture methodology.

Cupples, Michael; Coverstone, Vicki

2003-01-01

337

Multiplicity study of Herbig Ae/Be stars  

NASA Astrophysics Data System (ADS)

We present the results of a high resolution imaging survey to study the multiplicity of Herbig Ae/Be stars. 143 stars were observed with Adaptive Optics imaging, during two separate periods: 1993-1996 and 2005-2007. A total of 248 companions were detected, around 87 primary stars. 69 system were found to be likely true multiple systems, based on a statistical analysis. A complementary study for those stars for which multi-epoch data exists, confirms the results for almost all of the stars of this subset providing their proper motion is large enough and the multi-epoch data spanned a long enough time period.

Van Der Bliek, Nicole S.; Thomas, Sandrine; Rodgers, Bernadette; Bouvier, Jerome; Araya, Claudia; Doppmann, Greg; Cordero, Maria Jose

2014-06-01

338

Impact of solar system exploration on theories of chemical evolution and the origin of life  

NASA Technical Reports Server (NTRS)

The impact of solar system exploration on theories regarding chemical evolution and the origin of life is examined in detail. Major findings from missions to Mercury, Venus, the moon, Mars, Jupiter, Saturn, and Titan are reviewed and implications for prebiotic chemistry are discussed. Among the major conclusions are: prebiotic chemistry is widespread throughout the solar system and universe; chemical evolution and the origin of life are intimately associated with the origin and evolution of the solar system; the rate, direction, and extent of prebiotic chemistry is highly dependent upon planetary characteristics; and continued exploration will increase understanding of how life originated on earth and allow better estimates of the likelihood of similar processes occurring elsewhere.

Devincenzi, D. L.

1983-01-01

339

Potential uranium supply system based upon computer simulation of sequential exploration and decisions under risk  

SciTech Connect

A Monte Carlo simulation system was used to estimate potential supply of roll-type deposits. The system takes a given uranium-endowment probability distribution and aims at two major and interrelated objectives: (1) to design a system that estimates potential supply even when prices are much higher than previous or current prices; and (2) to account fully for the cost of discovering and mining the individual mineral deposits contained in given endowment. Achievement of these objectives constitutes the major contribution of this study. To accomplish them, the system considers: cost of risk, return on investment, cost of failures during the search process, discovery depletion, and effect of physical characteristics of the deposits on exploration and mining costs. It also considers that when economic conditions, such as product price, are outside historical experience, existing behavioral rules - exploration drilling density, stopping rules, minimum attractive deposit size and grade, and mining parameters - are irrelevant. The system architecture is general and can be used with an exploration model prepared specifically for other minerals.

Ortiz-Vertiz, S.R.

1991-01-01

340

AES And XPS Study of Plutonium Oxidation.  

National Technical Information Service (NTIS)

The initial oxidation of plutonium metal at 27 exp 0 C has been studied using AES and XPS. Initially a clean plutonium surface was prepared by Ar exp + bombardment and 500 exp 0 C-Ar exp + bombardment heat cycles. Changes occurring in the plutonium Auger ...

D. T. Larson

1979-01-01

341

The FUSE satellite is moved to a payload attach fitting in Hangar AE, Cape Canaveral Air Station  

NASA Technical Reports Server (NTRS)

Workers at Hangar AE, Cape Canaveral Air Station, maneuver an overhead crane toward NASA's Far Ultraviolet Spectroscopic Explorer (FUSE) satellite standing between vertical workstands. The crane will lift FUSE to move it onto the Payload Attach Fitting (PAF) in front of it. FUSE is undergoing a functional test of its systems, plus installation of flight batteries and solar arrays. Developed by The Johns Hopkins University under contract to Goddard Space Flight Center, Greenbelt, Md., FUSE will investigate the origin and evolution of the lightest elements in the universe - hydrogen and deuterium. In addition, the FUSE satellite will examine the forces and process involved in the evolution of the galaxies, stars and planetary systems by investigating light in the far ultraviolet portion of the electromagnetic spectrum. FUSE is scheduled to be launched May 27 aboard a Boeing Delta II rocket at Launch Complex 17.

1999-01-01

342

The FUSE satellite is moved to a payload attach fitting in Hangar AE, Cape Canaveral Air Station  

NASA Technical Reports Server (NTRS)

While a crane lifts NASA's Far Ultraviolet Spectroscopic Explorer (FUSE) satellite, workers at Hangar AE, Cape Canaveral Air Station, help guide it toward the circular Payload Attach Fitting (PAF) in front of it. FUSE is undergoing a functional test of its systems, plus installation of flight batteries and solar arrays. Developed by The Johns Hopkins University under contract to Goddard Space Flight Center, Greenbelt, Md., FUSE will investigate the origin and evolution of the lightest elements in the universe - hydrogen and deuterium. In addition, the FUSE satellite will examine the forces and process involved in the evolution of the galaxies, stars and planetary systems by investigating light in the far ultraviolet portion of the electromagnetic spectrum. FUSE is scheduled to be launched May 27 aboard a Boeing Delta II rocket at Launch Complex 17.

1999-01-01

343

Exploring Online Learning at Primary Schools: Students' Perspectives on Cyber Home Learning System through Video Conferencing (CHLS-VC)  

ERIC Educational Resources Information Center

The purposes of the study are to investigate CHLS (Cyber Home Learning System) in online video conferencing environment in primary school level and to explore the students' responses on CHLS-VC (Cyber Home Learning System through Video Conferencing) in order to explore the possibility of using CHLS-VC as a supportive online learning system. The…

Lee, June; Yoon, Seo Young; Lee, Chung Hyun

2013-01-01

344

System for Multiplexing Acoustic Emission (AE) Instrumentation.  

National Technical Information Service (NTIS)

An acoustic monitoring device has at least two acoustic sensors with a triggering mechanism and a multiplexing circuit. After the occurrence of a triggering event at a sensor, the multiplexing circuit allows a recording component to record acoustic emissi...

D. F. Perey E. F. Scales M. R. Gorman W. H. Prosser

2003-01-01

345

Human Factors Engineering as a System in the Vision for Exploration  

NASA Technical Reports Server (NTRS)

In order to accomplish NASA's Vision for Exploration, while assuring crew safety and productivity, human performance issues must be well integrated into system design from mission conception. To that end, a two-year Technology Development Project (TDP) was funded by NASA Headquarters to develop a systematic method for including the human as a system in NASA's Vision for Exploration. The specific goals of this project are to review current Human Systems Integration (HSI) standards (i.e., industry, military, NASA) and tailor them to selected NASA Exploration activities. Once the methods are proven in the selected domains, a plan will be developed to expand the effort to a wider scope of Exploration activities. The methods will be documented for inclusion in NASA-specific documents (such as the Human Systems Integration Standards, NASA-STD-3000) to be used in future space systems. The current project builds on a previous TDP dealing with Human Factors Engineering processes. That project identified the key phases of the current NASA design lifecycle, and outlined the recommended HFE activities that should be incorporated at each phase. The project also resulted in a prototype of a webbased HFE process tool that could be used to support an ideal HFE development process at NASA. This will help to augment the limited human factors resources available by providing a web-based tool that explains the importance of human factors, teaches a recommended process, and then provides the instructions, templates and examples to carry out the process steps. The HFE activities identified by the previous TDP are being tested in situ for the current effort through support to a specific NASA Exploration activity. Currently, HFE personnel are working with systems engineering personnel to identify HSI impacts for lunar exploration by facilitating the generation of systemlevel Concepts of Operations (ConOps). For example, medical operations scenarios have been generated for lunar habitation in order to identify HSI requirements for the lunar communications architecture. Throughout these ConOps exercises, HFE personnel are testing various tools and methodologies that have been identified in the literature. A key part of the effort is the identification of optimal processes, methods, and tools for these early development phase activities, such as ConOps, requirements development, and early conceptual design. An overview of the activities completed thus far, as well as the tools and methods investigated will be presented.

Whitmore, Mihriban; Smith, Danielle; Holden, Kritina

2006-01-01

346

SEEDS-The international postgraduate master program for preparing young systems engineers for space exploration  

NASA Astrophysics Data System (ADS)

SpacE Exploration and Development Systems (SEEDS) initiative originated from Politecnico di Torino and Thales Alenia Space Italy in 2005. It aimed at establishing a postgraduate international master course in space exploration and development systems to offer an opportunity to young engineers to get prepared for the future of Europe in space exploration. SEEDS project has been shared with Supaero Toulouse in France and with University of Bremen (together with the Center of Applied Space Technology and Microgravity, ZARM) in Germany. SEEDS course comprises of two different steps in sequence: an initial learning phase and a project work phase. The distinguishing feature of SEEDS is without any doubt the project work phase, which includes the preparatory work and the conceptual design activities, performed in three European sites to develop a limited number of building blocks identified during the preparatory work. The first year of activity started in November 2005. Five years of activities have passed since then and five project works have been successfully completed, dealing with various space exploration themes. The paper focuses on the description of SEEDS master course, in terms of master course structure, applied methodology and students team organization, and on the main results achieved, in terms of project work activities and development of future space workforce. The positive experience of five years of SEEDS is brought to evidence and lessons learned are discussed in view of SEEDS continuation.

Vallerani, Ernesto; Chiocchia, Gianfranco; Messidoro, Piero; Perino, Maria Antonietta; Viola, Nicole

2013-02-01

347

Nuclear electric propulsion: A better, safer, cheaper transportation system for human exploration of Mars  

NASA Technical Reports Server (NTRS)

NASA has completed a preliminary mission and systems study of nuclear electric propulsion (NEP) systems for 'split-sprint' human exploration and related robotic cargo missions to Mars. This paper describes the study, the mission architecture selected, the NEP system and technology development needs, proposed development schedules, and estimated development costs. Since current administration policy makers have delayed funding for key technology development activities that could make Mars exploration missions a reality in the near future, NASA will have time to evaluate various alternate mission options, and it appears prudent to ensure that Mars mission plans focus on astronaut and mission safety, while reducing costs to acceptable levels. The split-sprint nuclear electric propulsion system offers trip times comparable to nuclear thermal propulsion (NTP) systems, while providing mission abort opportunities that are not possible with 'reference' mission architectures. Thus, NEP systems offer short transit times for the astronauts, reducing the exposure of the crew to intergalactic cosmic radiation. The high specific impulse of the NEP system, which leads to very low propellant requirements, results in significantly lower 'initial mass in low earth orbit' (IMLEO). Launch vehicle packaging studies show that the NEP system can be launched, assembled, and deployed, with about one less 240-metric-ton heavy lift launch vehicle (HLLV) per mission opportunity - a very Technology development cost of the nuclear reactor for an NEP system would be shared with the proposed nuclear surface power systems, since nuclear systems will be required to provide substantial electrical power on the surface of Mars. The NEP development project plan proposed includes evolutionary technology development for nuclear electric propulsion systems that expands upon SP-100 (Space Power - 100 kw(e)) technology that has been developed for lunar and Mars surface nuclear power, and small NEP systems for interplanetary probes. System upgrades are expected to evolve that will result in even shorter trip times, improved payload capabilities, and enhanced safety and reliability.

Clark, John S.; George, Jeffrey A.; Gefert, Leon P.; Doherty, Michael P.; Sefcik, Robert J.

1994-01-01

348

Where Space Comes Down to Earth: Test Facilities for Exploration Systems  

NASA Astrophysics Data System (ADS)

The NASA Glenn Research Center's (GRC's) Plum Brook Station has a complement of unique, highly capable facilities that can test space flight hardware ranging from development testing at the component, subsystem and system levels up to environmental qualification of very large spacecraft and extraterrestrial surface systems. The facilities can simulate the conditions of free space or the surfaces of the Moon or Mars, including atmospheric pressure and content, temperature and day/night cycles. This paper presents information on the facilities at the Plum Brook Station as they apply to the development of space systems that support the Vision for Space Exploration, and cites specific examples of testing to illustrate those capabilities.

Woytach, Jeffrey M.; Linne, Diane L.; Chambers, Jeffrey A.; Willis, Brian P.; Carek, Gerald A.

2007-01-01

349

Air and Water System (AWS) Design and Technology Selection for the Vision for Space Exploration  

NASA Technical Reports Server (NTRS)

This paper considers technology selection for the crew air and water recycling systems to be used in long duration human space exploration. The specific objectives are to identify the most probable air and water technologies for the vision for space exploration and to identify the alternate technologies that might be developed. The approach is to conduct a preliminary first cut systems engineering analysis, beginning with the Air and Water System (AWS) requirements and the system mass balance, and then define the functional architecture, review the International Space Station (ISS) technologies, and discuss alternate technologies. The life support requirements for air and water are well known. The results of the mass flow and mass balance analysis help define the system architectural concept. The AWS includes five subsystems: Oxygen Supply, Condensate Purification, Urine Purification, Hygiene Water Purification, and Clothes Wash Purification. AWS technologies have been evaluated in the life support design for ISS node 3, and in earlier space station design studies, in proposals for the upgrade or evolution of the space station, and in studies of potential lunar or Mars missions. The leading candidate technologies for the vision for space exploration are those planned for Node 3 of the ISS. The ISS life support was designed to utilize Space Station Freedom (SSF) hardware to the maximum extent possible. The SSF final technology selection process, criteria, and results are discussed. Would it be cost-effective for the vision for space exploration to develop alternate technology? This paper will examine this and other questions associated with AWS design and technology selection.

Jones, Harry; Kliss, Mark

2005-01-01

350

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

351

Entry, Descent and Landing Systems Analysis: Exploration Feed Forward Internal Peer Review Slide Package  

NASA Technical Reports Server (NTRS)

NASA senior management commissioned the Entry, Descent and Landing Systems Analysis (EDL-SA) Study in 2008 to identify and roadmap the Entry, Descent and Landing (EDL) technology investments that the agency needed to successfully land large payloads at Mars for both robotic and human-scale missions. Year 1 of the study focused on technologies required for Exploration-class missions to land payloads of 10 to 50 mt. Inflatable decelerators, rigid aeroshell and supersonic retro-propulsion emerged as the top candidate technologies. In Year 2 of the study, low TRL technologies identified in Year 1, inflatables aeroshells and supersonic retropropulsion, were combined to create a demonstration precursor robotic mission. This part of the EDL-SA Year 2 effort, called Exploration Feed Forward (EFF), took much of the systems analysis simulation and component model development from Year 1 to the next level of detail.

Dwyer Cianciolo, Alicia M. (Editor)

2011-01-01

352

A field gas chromatograph using technology developed for solar system exploration  

NASA Technical Reports Server (NTRS)

Trace gas analysis is an integral part of biospheric studies. Analytical instruments, primarily gas chromatographs (GC), are capable of measuring gases and volatiles to the ppb-level in real time. Trace gases significant in the study of biocycles include nitrous oxide, hydrogen sulfide, other nitrogen and sulfur species, as well as methane and ethylene. The concept of a field gas chromatograph is derived from technology being pursued in the design of ultra-compact instruments for solar system exploration. The instrument breadboard incorporates the specialized porous column packings and the highly sensitive metastable ionization detector developed by the Solar System Exploration Office. These parts ensure a broad capability for which the analysis of ambient N2O is one example. A commercial, portable gas chromatograph is currently being extensively modified to incorporate analytical concepts and components derived from flight GC technology. Data storage devices suitable for field use are presently being studied.

Woeller, F. H.; Lehwalt, M. E.; Carle, Glenn C.

1985-01-01

353

A Geothermal GIS for Nevada: Defining Regional Controls and Favorable Exploration Terrains for Extensional Geothermal Systems  

USGS Publications Warehouse

Spatial analysis with a GIS was used to evaluate geothermal systems in Nevada using digital maps of geology, heat flow, young faults, young volcanism, depth to groundwater, groundwater geochemistry, earthquakes, and gravity. High-temperature (>160??C) extensional geothermal systems are preferentially associated with northeast-striking late Pleistocene and younger faults, caused by crustal extension, which in most of Nevada is currently oriented northwesterly (as measured by GPS). The distribution of sparse young (160??C) geothermal systems in Nevada are more likely to occur in areas where the groundwater table is shallow (<30m). Undiscovered geothermal systems may occur where groundwater levels are deeper and hot springs do not issue at the surface. A logistic regression exploration model was developed for geothermal systems, using young faults, young volcanics, positive gravity anomalies, and earthquakes to predict areas where deeper groundwater tables are most likely to conceal geothermal systems.

Coolbaugh, M. F.; Taranik, J. V.; Raines, G. L.; Shevenell, L. A.; Sawatzky, D. L.; Bedell, R.; Minor, T. B.

2002-01-01

354

Challenges in verification and validation of autonomous systems for space exploration  

NASA Technical Reports Server (NTRS)

Space exploration applications offer a unique opportunity for the development and deployment of autonomous systems, due to limited communications, large distances, and great expense of direct operation. At the same time, the risk and cost of space missions leads to reluctance to taking on new, complex and difficult-to-understand technology. A key issue in addressing these concerns is the validation of autonomous systems. In recent years, higher-level autonomous systems have been applied in space applications. In this presentation, we will highlight those autonomous systems, and discuss issues in validating these systems. We will then look to future demands on validating autonomous systems for space, identify promising technologies and open issues.

Brat, Guillaume; Jonsson, Ari

2005-01-01

355

Highly Survivable Avionics Systems for Long-Term Deep Space Exploration  

Microsoft Academic Search

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

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

2001-01-01

356

Exploring the FDA adverse event reporting system to generate hypotheses for monitoring of disease characteristics.  

PubMed

The US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) is a database for postmarketing drug safety monitoring and influences changes in FDA safety guidance documents such as drug labels. The number of cases in the FAERS has rapidly increased with the improvement of submission methods and data standards and thus has become an important resource for regulatory science. Although the FAERS has been predominantly used for safety signal detection, this study explored its utility for disease characteristics. PMID:24448476

Fang, H; Su, Z; Wang, Y; Miller, A; Liu, Z; Howard, P C; Tong, W; Lin, S M

2014-05-01

357

Earth Exploration Toolbook: Using GLOBE Data to Study the Earth System  

NSDL National Science Digital Library

Students will be guided through the process of locating and graphing web-based environmental data that has been collected by GLOBE Program participants. This chapter highlights the opportunities for using GLOBE Program data to introduce basic concepts of Earth system science. It is part of the Earth Exploration Toolbook, which provides teachers and/or students with direct practice for using scientific tools to analyze Earth science data. Students should begin on the Case Study page.

358

MITEE: A new nuclear engine concept for ultra fast, lightweight solar system exploration missions  

Microsoft Academic Search

A new ultra compact nuclear engine concept, MITEE (MIniature R_eactor E_nginE_), is described, and its performance evaluated for various solar system exploration missions. The MITEE concept is based on the Particle Bed Reactor (PBR), with modifications that enable a smaller, lighter nuclear engine. A range of MITEE Engine designs is described. Representative design parameters for the baseline MITEE reactor are:

James Powell; John Paniagua; Hans Ludewig; George Maise; Michael Todosow

1998-01-01

359

Nuclear electric propulsion: A better, safer, cheaper transportation system for human exploration of Mars  

SciTech Connect

NASA has completed a preliminary mission and systems study of nuclear electric propulsion (NEP) systems for split-sprint' human exploration and related robotic cargo missions to Mars. This paper describes the study, the mission architecture selected, the NEP system and technology development needs, proposed development schedules, and estimated development costs. Since current administration policy makers have delayed funding for key technology development activities that could make Mars exploration missions a reality in the near future, NASA will have time to evaluate various alternate mission options, and it appears prudent to ensure that Mars mission plans focus on astronaut and mission safety, while reducing costs to acceptable levels. The split-sprint nuclear electric propulsion system offers trip times comparable to nuclear thermal propulsion (NTP) systems, while providing mission abort opportunities that are not possible with reference' mission architectures. Thus, NEP systems offer short transit times for the astronauts, reducing the exposure of the crew to intergalactic cosmic radiation. The high specific impulse of the NEP system, which leads to very low propellant requirements, results in significantly lower initial mass in low earth orbit' (IMLEO). Launch vehicle packaging studies show that the NEP system can be launched, assembled, and deployed, with about one less 240-metric-ton heavy lift launch vehicle (HLLV) per mission opportunity - a very Technology development cost of the nuclear reactor for an NEP system would be shared with the proposed nuclear surface power systems, since nuclear systems will be required to provide substantial electrical power on the surface of Mars. The NEP development project plan proposed includes evolutionary technology development for nuclear electric propulsion systems that expands upon SP-100 (Space Power - 100 kw(e)) technology that has been developed for lunar and Mars surface nuclear power.

Clark, J.S.; George, J.A.; Gefert, L.P.; Doherty, M.P.; Sefcik, R.J.

1994-03-01

360

New Propulsion Technologies For Exploration of the Solar System and Beyond  

NASA Technical Reports Server (NTRS)

In order to implement the ambitious science and exploration missions planned over the next several decades, improvements in in-space transportation and propulsion technologies must be achieved. For robotic exploration and science missions, increased efficiencies of future propulsion systems are critical to reduce overall life-cycle costs. Future missions will require 2 to 3 times more total change in velocity over their mission lives than the NASA Solar Electric Technology Application Readiness (NSTAR) demonstration on the Deep Space 1 mission. Rendezvous and return missions will require similar investments in in-space propulsion systems. New opportunities to explore beyond the outer planets and to the stars will require unparalleled technology advancement and innovation. The Advanced Space Transportation Program (ASTP) is investing in technologies to achieve a factor of 10 reduction in the cost of Earth orbital transportation and a factor of 2 reduction in propulsion system mass and travel time for planetary missions within the next 15 years. Since more than 70% of projected launches over the next 10 years will require propulsion systems capable of attaining destinations beyond Low Earth Orbit, investment in in-space technologies will benefit a large percentage of future missions. The ASTP technology portfolio includes many advanced propulsion systems. From the next generation ion propulsion system operating in the 5 - 10 kW range, to fission-powered multi-kilowatt systems, 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 on-board fuel to achieve thrust. An overview of the state-of-the-art in propellantless propulsion technologies such as solar and plasma sails, electrodynamic and momentum transfer tethers, and aeroassist and aerocapture will also be described. Results of recent earth-based technology demonstrations and space tests for many of these new propulsion technologies will be discussed.

Johnson, Les; Cook, Stephen (Technical Monitor)

2001-01-01

361

Lunar Science Missions in Context of the Decadal Solar System Exploration Survey  

NASA Astrophysics Data System (ADS)

Over the last year a broad and detailed assessment of the current status of science activities as well as research strategies for solar system exploration (SSE) was undertaken by a sub-committee of the NAS/NRC Space Studies Board. This study was requested by NASA to identify science priorities for the next decade of exploration. The report has been completed and is in the review process. This Decadal SSE Survey report is to be given to Dr. Ed Weiler, Associate Administrator for Space Science. It will be publicly released during the summer of 2002 in time for use in NASA's strategic planning. The study consisted of individual panels charged with making recommendations for particular aspects of solar system exploration and a Steering Committee, chaired by Mike Belton, who prepared an overview of compelling solar system science and identified cross-cutting issues. The panels prepared detailed reports that were submitted to the Steering Committee. The Steering Committee, which also contained a representative from each of the panels, prioritized the diverse panel recommendations into an integrated strategy, including prioritized recommendations.

Pieters, C. M.; Bullock, M.; Greeley, R.; Jolliff, B.; Sprague, A.; Stofan, E.

2002-01-01

362

Planning for Planetary Protection and Contamination Control for In Situ Solar System Exploration  

NASA Astrophysics Data System (ADS)

In-situ missions present new architectural and technical challenges in planetary protection where planetary protection preserves the chemical environment of a target body for future life-detection exploration and in sample return missions protects the Earth from potential extraterrestrial contamination The National Research Council s Decadal Survey of 2003 and the NASA Solar System Exploration Strategic Program roadmap of 2005 calls for a number of missions with in-situ analysis at bodies of interest for life-detection or prebiotic science including Europa Titan and comets These targets present challenges because NASA planetary protection policies specify new requirements for missions to Europa and new guidelines for Titan are anticipated furthermore the comet missions have additional significance because they are envisioned to be sample return missions Many of these challenges differ substantially from those seen on Mars and will require novel approaches and solutions In addition the scientific contamination control requirements are likely to require additional planning and technology development early consideration of these needs may lead to solutions that overlap with planetary protection implementation This presentation summarizes the technical challenges to planetary protection and contamination control for these targets of interest and outlines some of the considerations particularly at the system level in designing an appropriate technology investment strategy for in situ solar system exploration

Belz, A. P.; Cutts, J. A.

363

NASA Exploration Launch Projects Systems Engineering Approach for Astronaut Missions to the Moon, Mars, and Beyond  

NASA Technical Reports Server (NTRS)

The U.S. Vision for Space Exploration directs NASA to design and develop a new generation of safe, reliable, and cost-effective transportation systems to hlfill the Nation s strategic goals and objectives. These launch vehicles will provide the capability for astronauts to conduct scientific exploration that yields new knowledge from the unique vantage point of space. American leadership in opening new fi-ontiers will improve the quality of life on Earth for generations to come. The Exploration Launch Projects office is responsible for delivering the Crew Launch Vehicle (CLV) that will loft the Crew Exploration Vehicle (CEV) into low-Earth orbit (LEO) early next decade, and for the heavy lift Cargo Launch Vehicle (CaLV) that will deliver the Lunar Surface Access Module (LSAM) to LEO for astronaut return trips to the Moon by 2020 in preparation for the eventual first human footprint on Mars. Crew travel to the International Space Station will be made available as soon possible after the Space Shuttle retires in 2010.

Cook, Stephen A.; Dumbacher, Daniel L.

2006-01-01

364

Telecommunication system specific to high temperature environment for JAXA Mercury exploration program  

NASA Astrophysics Data System (ADS)

BepiColombo is the joint Mercury exploration program between JAXA (Japan Aerospace Exploration Agency) and ESA (European Space Agency). MMO (Mercury Magnetospheric Orbiter) is JAXA's satellite in this program. She requires a telecommunication system that survives a harsh heat environment surrounding Mercury. She will stay in a polar orbit circulating Mercury for a year for continuous observations of Mercury magnetosphere. MMO has an X-band telecommunication system. We newly developed a high gain antenna for the use of her daily operations and wider field of view antennas for critical events. They are ones directly exposed to a high temperature environment of Mercury. The remains of the telecommunication system such as a transponder and a power amplifier were selected from the heritage of our past deep space missions. These instruments are placed inside MMO where a milder environment is expected than the outside. The total telecommunication system has been designed so that it should work through the MMO mission lifetime from the launch in 2016 to the end of the mission in 2025 including an extra year of extension. The system has experienced thermal environmental tests and proved its excellent resistivity to predicted environments. We will discuss these technologies incorporated in MMO and her telecommunication system design.

Toda, Tomoaki; Kamata, Yukio; Kawahara, Kousuke; Maejima, Hironori; Hayakawa, Hajime

2014-02-01

365

An Exploration of Exertion in Mixed Reality Systems via the ``Table Tennis for Three'' Game  

NASA Astrophysics Data System (ADS)

Humans experience their physical and social environment through their bodies and their associated movement actions. However, most mixed reality systems approach the integration of the real with a virtual world from a computational perspective, often neglecting the body’s capabilities by offering only limited interaction possibilities with a few augmented tangible objects. We propose a view on mixed reality systems that focuses on the human body and its movements, because we believe such an approach has the potential to support novel interaction experiences, as explored by a prototypal gaming system that was inspired by exertion actions exhibited in table tennis. “Table Tennis for Three” enables augmented bodily experiences while offering new opportunities for interaction, such as supporting three players simultaneously across geographical distances. This case study offers an exploration of the role of the human body and its associated movement actions in mixed reality systems, aiming to contribute toward an understanding of the use of exertion in such systems. Such an understanding can support leveraging the many benefits of exertion through mixed reality systems and therefore guide future advances in this research field.

Mueller, Florian ‘Floyd'; Gibbs, Martin R.; Vetere, Frank

366

Meaningful Understanding and Systems Thinking in Organic Chemistry: Validating Measurement and Exploring Relationships  

NASA Astrophysics Data System (ADS)

The purpose of this study was dual: First, to develop and validate assessment schemes for assessing 11th grade students' meaningful understanding of organic chemistry concepts, as well as their systems thinking skills in the domain. Second, to explore the relationship between the two constructs of interest based on students' performance on the applied assessment framework. For this purpose, (a) various types of objective assessment questions were developed and evaluated for assessing meaningful understanding, (b) a specific type of systemic assessment questions (SAQs) was developed and evaluated for assessing systems thinking skills, and (c) the association between students' responses on the applied assessment schemes was explored. The results indicated that properly designed objective questions can effectively capture aspects of students' meaningful understanding. It was also found that the SAQs can elicit systems thinking skills in the context of a formalistic systems thinking theoretical approach. Moreover, a significant relationship was observed between students' responses on the two assessment strategies. This research provides evidence that students' systems thinking level within a science domain is significantly related to their meaningful understanding of relative science concepts.

Vachliotis, Theodoros; Salta, Katerina; Tzougraki, Chryssa

2014-04-01

367

Avionics Architectures for Exploration: Building a Better Approach for (Human) Spaceflight Avionics  

NASA Technical Reports Server (NTRS)

The field of Avionics is advancing far more rapidly in terrestrial applications than in space flight applications. Spaceflight Avionics are not keeping pace with expectations set by terrestrial experience, nor are they keeping pace with the need for increasingly complex automation and crew interfaces as we move beyond Low Earth Orbit. NASA must take advantage of the strides being made by both space-related and terrestrial industries to drive our development and sustaining costs down. This paper describes ongoing efforts by the Avionics Architectures for Exploration (AAE) project chartered by NASA's Advanced Exploration Systems (AES) Program to evaluate new avionic architectures and technologies, provide objective comparisons of them, and mature selected technologies for flight and for use by other AES projects. Results from the AAE project's FY13 efforts are discussed, along with the status of FY14 efforts and future plans.

Goforth, Montgomery B.; Ratliff, James E.; Hames, Kevin L.; Vitalpur, Sharada V.

2014-01-01

368

Exploring Mars  

NSDL National Science Digital Library

This module from the Mars Exploration Curriculum serves as an introduction to studying Mars in the classroom develops students' understanding of Mars, the solar system, and planetary exploration. The module introduces many of the intriguing riddles posed by Mars and provides teachers a variety of ways to integrate the study of Mars into their classrooms.

369

A multitasking behavioral control system for the Robotic All-Terrain Lunar Exploration Rover (RATLER)  

NASA Technical Reports Server (NTRS)

An approach for a robotic control system which implements so called 'behavioral' control within a realtime multitasking architecture is proposed. The proposed system would attempt to ameliorate some of the problems noted by some researchers when implementing subsumptive or behavioral control systems, particularly with regard to multiple processor systems and realtime operations. The architecture is designed to allow synchronous operations between various behavior modules by taking advantage of a realtime multitasking system's intertask communications channels, and by implementing each behavior module and each interconnection node as a stand-alone task. The potential advantages of this approach over those previously described in the field are discussed. An implementation of the architecture is planned for a prototype Robotic All Terrain Lunar Exploration Rover (RATLER) currently under development and is briefly described.

Klarer, Paul

1993-01-01

370

Exploring hyper-cubic energy landscapes in thermally active finite artificial spin-ice systems  

NASA Astrophysics Data System (ADS)

Two-dimensional artificial spin-ice systems constructed from arrays of dipolar coupled monodomain magnets offer an experimental route to study the physics of frustration and a corresponding degeneracy that grows exponentially with system size. However, so far, such systems remain mainly frozen below their magnet's Curie temperature, unable to explore their potential-energy landscape through thermal fluctuations. Here we demonstrate the creation of thermally active finite artificial spin-ice systems and the observation of magnetic fluctuations in real time and space. We show that the subsequent magnetization dynamics can be entirely understood from the underlying dipolar energy landscape, and demonstrate that both the energy scale and the complexity of the landscape affect the temporal and spatial nature of the observed configurational changes. This work paves the way for the in situ study of thermally induced magnetic relaxation processes and delivers a controlled route to the lowest-energy state in extended two-dimensional artificial spin-ice systems.

Farhan, A.; Derlet, P. M.; Kleibert, A.; Balan, A.; Chopdekar, R. V.; Wyss, M.; Anghinolfi, L.; Nolting, F.; Heyderman, L. J.

2013-06-01

371

Solid Earth Science Data System for Exploration of Lithospheric Deformation in the Western US  

NASA Astrophysics Data System (ADS)

The primary objective of this project is to generate long-term consistent surface deformation Earth Science Data Records (ESDRs) by infusing science product generation, visualization, and manipulation tools and information technology, prototyped under NASA’s REASoN, ACCESS and SENH programs, into an end-to-end operational Science Data System. The products include geodetic daily position time series, crustal motion velocities, and strain and strain rate maps. These data products will be at the level just below interpretation. They will make scientific discoveries from EarthScope’s Plate Boundary Observatory (PBO) and other GPS networks more accessible to the broad community of geophysics researchers and students by providing them these data products through a science data portal with integrated product exploration and modeling tools. Data products and web-based modeling tool are made accessible through a portal called GPS Explorer (http://geoapp03.ucsd.edu/gridsphere/gridsphere) that allows scientific users to explore and manipulate these products and data sets in a workbench-like environment. The tools allow users to explore geophysical parameters in response to earthquakes and volcanic events within the PBO and greater western North America region. This IT system has been designed using modern IT tools and principles in order to be extensible to any geographic location, scale, natural hazard, and combination of geophysical sensor and related data. We have built upon open GIS standards, particularly those of the OGC, and have used the principles of Web Service-based Service Oriented Architectures to provide scalability and extensibility. We will present how we have brought this IT infrastructure and these product generation tools to a mature, flexible and expandable science data system.

Webb, F.; Bock, Y.; Kedar, S.; Owen, S. E.; Dong, D.; Jamason, P.; Fang, P.; Squibb, M. B.; Crowell, B. W.; Avraham, D.

2009-12-01

372

A technology assessment of alternative communications systems for the space exploration initiative  

NASA Technical Reports Server (NTRS)

Telecommunications, Navigation, and Information Management (TNIM) services are vital to accomplish the ambitious goals of the Space Exploration Initiative (SEI). A technology assessment is provided for four alternative lunar and Mars operational TNIM systems based on detailed communications link analyses. The four alternative systems range from a minimum to a fully enhanced capability and use frequencies from S-band, through Ka-band, and up to optical wavelengths. Included are technology development schedules as they relate to present SEI mission architecture time frames.

Ponchak, Denise S.; Zuzek, John E.; Whyte, Wayne A., Jr.; Spence, Rodney L.; Sohn, Philip Y.

1990-01-01

373

AE mass spectrometer antechamber study  

NASA Technical Reports Server (NTRS)

The formation of CO2 and H2O in a gold plated antechamber was investigated when a beam of oxygen is introduced. It was found that at room temperature the formation of CO2 and H2O is negligibly small. However, at the top temperature (197 C) which could be achieved with the existing system, both products were formed in significant quantities. Desorption of CO2 and H2O at this temperature is still slow and incomplete which accounts for the delayed response to the beam conditions. Although the catalytic reactions take place already with molecular oxygen, the reactions are significantly enhanced if the oxygen beam is partially dissociated.

Herzog, R. F.

1971-01-01

374

Opening the Solar System: An Advanced Nuclear Spacecraft for Human Exploration  

NASA Technical Reports Server (NTRS)

Human exploration of the solar system is limited by our technology, not our imagination. We dream of a time when we can freely travel among the planets and truly become a spacefaring people. However, the current state of our technology limits our options for architecting missions to other planets. Instead of sailing the seas of space in the way that we cruise the seas of Earth, our limited propulsion technology requires us to depart Earth on a giant cluster of gas tanks and return in a lifeboat. This inefficient approach to exploration is evident in many of today's leading mission plans for human flights to Mars, asteroids, and other destinations. The cost and complexity of this approach to mission architecting makes it extremely difficult to realize our dreams of exploration beyond Low Earth Orbit (LEO). This does not need to be the case. Researchers at NASA's Marshall Space Flight Center (MSFC) have been investigating the feasibility of a new take on nuclear propulsion with the performance to enable a paradigm shift in human space exploration. During the fall of 2013, engineers at MSFC's Advanced Concepts Office developed a spacecraft concept (pictured below) around this new propulsion technology and redefined the human Mars mission to show its full potential. This spacecraft, which can be launched with a fleet of soon-to-be available SLS launch vehicles, is fueled primarily with hydrogen, and is fully reusable with no staging required. The reusable nature of this design enables a host of alternative mission architectures that more closely resemble an ocean voyage than our current piecemeal approach to exploration.

Werka, R. O.; Percy, T. K.

2014-01-01

375

Lunar precursor missions for human exploration of Mars--III: studies of system reliability and maintenance  

NASA Technical Reports Server (NTRS)

Discussions of future human expeditions into the solar system generally focus on whether the next explorers ought to go to the Moon or to Mars. The only mission scenario developed in any detail within NASA is an expedition to Mars with a 500-day stay at the surface. The technological capabilities and the operational experience base required for such a mission do not now exist nor has any self-consistent program plan been proposed to acquire them. In particular, the lack of an Abort-to-Earth capability implies that critical mission systems must perform reliably for 3 years or must be maintainable and repairable by the crew. As has been previously argued, a well-planned program of human exploration of the Moon would provide a context within which to develop the appropriate technologies because a lunar expedition incorporates many of the operational elements of a Mars expedition. Initial lunar expeditions can be carried out at scales consistent with the current experience base but can be expanded in any or all operational phases to produce an experience base necessary to successfully and safely conduct human exploration of Mars. Published by Elsevier Ltd.

Mendell, W. W.; Heydorn, R. P.

2004-01-01

376

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

377

An ASIC Implementation of the AES SBoxes  

Microsoft Academic Search

This article presents a hardware implementation of the SBoxes from the Advanced Encryption Standard (AES). The SBoxes substitute\\u000a an 8-bit input for an 8-bit output and are based on arithmetic operations in the finite field GF(28). We show that a calculation of this function and its inverse can be done efficiently with combinational logic. This approach\\u000a has advantages over a

Johannes Wolkerstorfer; Elisabeth Oswald; Mario Lamberger

2002-01-01

378

Multiwavelength campaign of observations of AE Aqr.  

NASA Astrophysics Data System (ADS)

We provide a summary of results, obtained from a multiwavelength (TeV gamma -ray, X-ray, UV, optical, and radio) campaign of observations of AE Aqr conducted in 2005 August 28-September 2, on the nature and correlation of the flux variations in the various wavebands, the white dwarf spin evolution, the properties of the X-ray emission region, and the very low upper limits on the TeV gamma -ray flux.

Mauche, C. W.; Abada-Simon, M.; Desmurs, J.-F.; Dulude, M. J.; Ioannou, Z.; Neill, J. D.; Price, A.; Sidro, N.; Welsh, W. F.; AAVSO CBA

379

Magnetic fields in Herbig Ae stars  

Microsoft Academic Search

Herbig Ae stars are young A-type stars in the pre-main sequence evolutionary phase with masses of ˜1.5-3 M&sun;. They show rather intense surface activity (Dunkin et al. \\\\cite{Du97}, MNRAS, 290, 165) and infrared excess related to the presence of circumstellar disks. Because of their youth, primordial magnetic fields inherited from the parent molecular cloud may be expected, but no direct

S. Hubrig; M. Schöller; R. V. Yudin

2004-01-01

380

AES-CBC software execution optimization  

Microsoft Academic Search

With the proliferation of high-speed wireless networking, the necessity for efficient, robust and secure encryption modes is ever increasing. But, cryptography is primarily a computationally intensive process. This paper investigates the performance and efficiency of IEEE 802.11i approved Advanced Encryption Standard (AES)-Rijndael ciphering\\/deciphering software in Cipher Block Chaining (CBC) mode. Simulations are used to analyse the speed, resource consumption and

Razvi Doomun; Jayramsingh Doma; Sundeep Tengur

2008-01-01

381

Cascade Storage and Delivery System for a Multi Mission Space Exploration Vehicle (MMSEV)  

NASA Technical Reports Server (NTRS)

NASA is developing a Multi Mission Space Exploration Vehicle (MMSEV) for missions beyond Low Earth Orbit (LEO). The MMSEV is a pressurized vehicle used to extend the human exploration envelope for Lunar, Near Earth Object (NEO), and Deep Space missions. The Johnson Space Center is developing the Environmental Control and Life Support System (ECLSS) for the MMSEV. The MMSEV s intended use is to support longer sortie lengths with multiple Extra Vehicular Activities (EVAs) on a higher magnitude than any previous vehicle. This paper presents an analysis of a high pressure oxygen cascade storage and delivery system that will accommodate the crew during long duration Intra Vehicular Activity (IVA) and capable of multiple high pressure oxygen fills to the Portable Life Support System (PLSS) worn by the crew during EVAs. A cascade is a high pressure gas cylinder system used for the refilling of smaller compressed gas cylinders. Each of the large cylinders are filled by a compressor, but the cascade system allows small cylinders to be filled without the need of a compressor. In addition, the cascade system is useful as a "reservoir" to accommodate low pressure needs. A regression model was developed to provide the mechanism to size the cascade systems subject to constraints such as number of crew, extravehicular activity duration and frequency, and ullage gas requirements under contingency scenarios. The sizing routine employed a numerical integration scheme to determine gas compressibility changes during depressurization and compressibility effects were captured using the Soave-Redlich-Kwong (SRK) equation of state. A multi-dimensional nonlinear optimization routine was used to find the minimum cascade tank system mass that meets the mission requirements. The sizing algorithms developed in this analysis provide a powerful framework to assess cascade filling, compressor, and hybrid systems to design long duration vehicle ECLSS architecture. 1

Yagoda, Evan; Swickrath, Michael; Stambaugh, Imelda

2012-01-01

382

Crustal stress, seismicity, acoustic emission (AE), and tectonics: the Kefallinì;a (Greece) case study  

NASA Astrophysics Data System (ADS)

New inferences - confirming previous results (see references)- are presented dealing with a few years Acoustic Emission (AE) records collected at Kefallinìa (Ionian Islands, Greece). A physical distinction between HF (high frequency) vs. LF (low frequency) AE is required. Step-wise changes of the AE underground conductivity are evidenced, and can be suitably handled. "Smooth" results concern (i) the annual variation, (ii) some long-lasting stress "solitons" crossing through the area, and (iii) tidal effects. In particular, every AE station can be operated like a monitoring station both for Earth's tides and for the free oscillations of the Earth. In addition, Kefallinìa exhibits a much peculiar groundwater circulation, in which conduit flow is dominant, that originates a specific (and unique) AE effect. By means of AE time-series analysis, "extreme" or "catastrophic" events can be also monitored and possibly related to relevant tectonic occurrences (either earthquakes, or maybe other occasional phenomena). They can be investigated, and have a regional - rather than local - character. Therefore, every interpretation based on a single station record - being biased by some arbitrariness - can only result indicative. A standardized procedure and software is proposed for routine AE data handling and analysis. References.: Lagios et al., 2004. In Proc. SCI 2004 (The 8th World Multi-Conference on Systemics, Cybernetics and Informatic), Orlando, Florida, July 1004, 6 pp. Poscolieri et al., 2006. In. G. Cello and B. D. Malamud, (eds), 2006. Geol. Soc. London, Special Publ., 261, 63-78. Poscolieri et al., 2006a. Nat. Hazards Earth Syst. Sci., 6, 961-971.

Gregori, G. P.; Poscolieri, M.; Paparo, G.; Ventrice, G.; de Simone, S.; Rafanelli, C.

2009-04-01

383

Locating the Accretion Footprint on a Herbig Ae Star: MWC 480  

NASA Technical Reports Server (NTRS)

Accretion is a fundamental process which establishes the dynamics of the protoplanetary disk and the final properties of the forming star. In solar-type stars, the star-disk coupling is determined by the magnetic field structure, which is responsible for funneling material from the disk midplane to higher latitudes on the star. Here, we use pan-chromatic data for the Herbig Ae star MWC 480 to address whether similar processes occur in intermediate-mass stars. MWC 480 has X-ray emission typical of actively accreting Herbig Ae stars, but with 5-9 x more photoelectric absorption than expected from optical and FUV data. We consider 3 sources for the absorption: the disk absorption in a wind or jet, and accretion. While we detect the disk in scattered light in are-analysis of archival HST data. the data are consistent with grazing illumination of the dust disk. We find that MWC 480's disk is stratified, geometrically thin, and is not responsible for the observed photoelectric absorption. MWC 480 drives a bipolar jet, but with a mass loss rate which is low compared to other Herbig Ae stars, where the outflow is more favorably oriented and enhanced photoelectric absorption is not seen. This excludes a jet or wind origin for the enhanced photoelectric absorption. We compare MWC 480's 0 VI emission with other Herbig Ae stars. The distribution of the emission in inclination, and lack of a correlation of profile shape and system inclination excludes equatorially-confined accretion for the FUSE Herbig Ae stars. The photoelectric absorption data further suggest that the accretion footprint on MWC 480 and other Herbig Ae stars is located at high temperate, rather than polar, latitudes. These findings support the presence of funneled accretion in MWC 480 and Herbig Ae stars, strengthening the parallel to T Tauri stars.

Grady, C. A.; Hamaguchi, K.; Schneider, G.; Stecklum, B.; Woodgate, B. E.; McCleary, J. E.; Williger, G. M.; Sitko, M. L.; Menard, F.; Henning, Th.; Brittain, S.; Troutmann, M.; Donehew, B.; Hines, D.; Wisniewski, J. P.; Lynch, D. K.; Russell, R. W.; Rudy, R. J.; Day, A. M.; Shenoy, A.; Wilner, D.; Silverston, M.; Bouret, J.-C.; Clampin, M.; Petre, R.

2011-01-01

384

Sources of Cognitive Exploration: Genetic Variation in the Prefrontal Dopamine System Predicts Openness/Intellect  

PubMed Central

The personality trait Openness/Intellect reflects the tendency to be imaginative, curious, perceptive, artistic, and intellectual—all characteristics that involve cognitive exploration. Little is known about the biological basis of Openness/Intellect, but the trait has been linked to cognitive functions of prefrontal cortex, and the neurotransmitter dopamine plays a key role in motivation to explore. The hypothesis that dopamine is involved in Openness/Intellect was supported by examining its association with two genes that are central components of the prefrontal dopaminergic system. In two demographically different samples (children: N = 608; adults: N = 214), variation in the dopamine D4 receptor gene (DRD4) and the catechol-O-methyltransferase gene (COMT) predicted Openness/Intellect, as main effects in the child sample and in interaction in adults.

DeYoung, Colin G.; Cicchetti, Dante; Rogosch, Fred A.; Gray, Jeremy R.; Eastman, Maria; Grigorenko, Elena L.

2011-01-01

385

Geophysical technique for mineral exploration and discrimination based on electromagnetic methods and associated systems  

DOEpatents

Mineral exploration needs a reliable method to distinguish between uneconomic mineral deposits and economic mineralization. A method and system includes a geophysical technique for subsurface material characterization, mineral exploration and mineral discrimination. The technique introduced in this invention detects induced polarization effects in electromagnetic data and uses remote geophysical observations to determine the parameters of an effective conductivity relaxation model using a composite analytical multi-phase model of the rock formations. The conductivity relaxation model and analytical model can be used to determine parameters related by analytical expressions to the physical characteristics of the microstructure of the rocks and minerals. These parameters are ultimately used for the discrimination of different components in underground formations, and in this way provide an ability to distinguish between uneconomic mineral deposits and zones of economic mineralization using geophysical remote sensing technology.

Zhdanov; Michael S. (Salt Lake City, UT) [Salt Lake City, UT

2008-01-29

386

Flight experience of solar mesosphere explorer's power system over high temperatures ranges  

NASA Technical Reports Server (NTRS)

The performance of the power system on the Solar Mesosphere Explorer (SME) satellite for the life of the mission and the techniques used to ensure power system health are summarized. Early in the mission high cell imbalances in one of the batteries resulted in a loading scheme which attempted to minimize the cell imbalances without causing an undervoltage condition. A short term model of the power system allowed planners to predict depth of discharge using the latest available data. Due to expected orbital shifts the solar arrays experience extended periods of no eclipse. This has required special conditioning schemes to keep the batteries healthy when the eclipses return. Analysis of the SME data indicates long term health of the SME power system as long as the conditioning scheme is continued.

Faber, Jack; Hurley, Daniel

1987-01-01

387

The implementation of the Human Exploration Demonstration Project (HEDP), a systems technology testbed  

NASA Technical Reports Server (NTRS)

The Human Exploration Demonstration Project (HEDP) is an ongoing task at the NASA's Ames Research Center to address the advanced technology requirements necessary to implement an integrated working and living environment for a planetary surface habitat. The integrated environment consists of life support systems, physiological monitoring of project crew, a virtual environment work station, and centralized data acquisition and habitat systems health monitoring. The HEDP is an integrated technology demonstrator, as well as an initial operational testbed. There are several robotic systems operational in a simulated planetary landscape external to the habitat environment, to provide representative work loads for the crew. This paper describes the evolution of the HEDP from initial concept to operational project; the status of the HEDP after two years; the final facilities composing the HEDP; the project's role as a NASA Ames Research Center systems technology testbed; and the interim demonstration scenarios that have been run to feature the developing technologies in 1993.

Rosen, Robert; Korsmeyer, David J.

1993-01-01

388

Developing an Automated Science Analysis System for Mars Surface Exploration for MSL and Beyond  

NASA Technical Reports Server (NTRS)

We are developing an automated science analysis system that could be utilized by robotic or human explorers on Mars (or even in remote locations on Earth) to improve the quality and quantity of science data returned. Three components of this system (our rock, layer, and horizon detectors) [1] have been incorporated into the JPL CLARITY system for possible use by MSL and future Mars robotic missions. Two other components include a multi-spectral image compression (SPEC) algorithm for pancam-type images with multiple filters and image fusion algorithms that identify the in focus regions of individual images in an image focal series [2]. Recently, we have been working to combine image and spectral data, and other knowledge to identify both rocks and minerals. Here we present our progress on developing an igneous rock detection system.

Gulick, V. C.; Hart, S. D.; Shi, X.; Siegel, V. L.

2004-01-01

389

Parametric Analysis of Life Support Systems for Future Space Exploration Missions  

NASA Technical Reports Server (NTRS)

Having adopted a flexible path approach to space exploration, the National Aeronautics and Space Administration is in a process of evaluating future targets for space exploration. In order to maintain the welfare of a crew during future missions, a suite of life support technology is responsible for oxygen and water generation, carbon dioxide control, the removal of trace concentrations of organic contaminants, processing and recovery of water, and the storage and reclamation of solid waste. For each particular life support subsystem, a variety competing technologies either exist or are under aggressive development efforts. Each individual technology has strengths and weaknesses with regard to launch mass, power and cooling requirements, volume of hardware and consumables, and crew time requirements for operation. However, from a system level perspective, the favorability of each life support architecture is better assessed when the sub-system technologies are analyzed in aggregate. In order to evaluate each specific life support system architecture, the measure of equivalent system mass (ESM) was employed to benchmark system favorability. Moreover, the results discussed herein will be from the context of loop-closure with respect to the air, water, and waste sub-systems. Specifically, closure relates to the amount of consumables mass that crosses the boundary of the vehicle over the lifetime of a mission. As will be demonstrated in this manuscript, the optimal level of loop closure is heavily dependent upon mission requirements such as duration and the level of extra- vehicular activity (EVA) performed. Sub-system level trades were also considered as a function of mission duration to assess when increased loop closure is practical. Although many additional factors will likely merit consideration in designing life support systems for future missions, the ESM results described herein provide a context for future architecture design decisions toward a flexible path program.

Swickrath, Michael J.; Anderson, Molly S.; Bagdigian, Bob M.

2010-01-01

390

Engineering America's Future in Space: Systems Engineering Innovations for Sustainable Exploration  

NASA Technical Reports Server (NTRS)

The National Aeronautics and Space Administration (NASA) delivers space transportation solutions for America's complex missions, ranging from scientific payloads that expand knowledge, such as the Hubble Space Telescope, to astronauts and lunar rovers destined for voyages to the Moon. Currently, the venerable Space Shuttle, which has been in service since 1981, provides U.S. capability for both crew and cargo to low-Earth orbit to construct the International Space Station, before the Shuttle is retired in 2010, as outlined in the 2006 NASA Strategic Plan. I In the next decade, NASA will replace this system with a duo of launch vehicles: the Ares I Crew Launch Vehicle/Orion Crew Exploration Vehicle and the Ares V Cargo Launch Vehicle/Altair Lunar Lander. The goals for this new system include increased safety and reliability, coupled with lower operations costs that promote sustainable space exploration over a multi-decade schedule. This paper will provide details of the in-house systems engineering and vehicle integration work now being performed for the Ares I and planned for the Ares V. It will give an overview of the Ares I system-level test activities, such as the ground vibration testing that will be conducted in the Marshall Center's Dynamic Test Stand to verify the integrated vehicle stack's structural integrity against predictions made by modern modeling and simulation analysis. It also will give information about the work in progress for the Ares I-X developmental test flight planned in 2009 to provide key data before the Ares I Critical Design Review. Activities such as these will help prove and refine mission concepts of operation, while supporting the spectrum of design and development tasks being performed by Marshall's Engineering Directorate, ranging from launch vehicles and lunar rovers to scientific spacecraft and associated experiments. Ultimately, the work performed will lead to the fielding of a robust space transportation solution that will carry international explorers and essential payloads for sustainable scientific discovery beyond planet Earth.

Dumbacher, Daniel L.; Jones, Carl P.

2008-01-01

391

Trade Study of System Level Ranked Radiation Protection Concepts for Deep Space Exploration  

NASA Technical Reports Server (NTRS)

A strategic focus area for NASA is to pursue the development of technologies which support exploration in space beyond the current inhabited region of low earth orbit. An unresolved issue for crewed deep space exploration involves limiting crew radiation exposure to below acceptable levels, considering both solar particle events and galactic cosmic ray contributions to dosage. Galactic cosmic ray mitigation is not addressed in this paper, but by addressing credible, easily implemented, and mass efficient solutions for the possibility of solar particle events, additional margin is provided that can be used for cosmic ray dose accumulation. As a result, NASA s Advanced Engineering Systems project office initiated this Radiation Storm Shelter design activity. This paper reports on the first year results of an expected 3 year Storm Shelter study effort which will mature concepts and operational scenarios that protect exploration astronauts from solar particle radiation events. Large trade space definition, candidate concept ranking, and a planned demonstration comprised the majority of FY12 activities. A system key performance parameter is minimization of the required increase in mass needed to provide a safe environment. Total system mass along with operational assessments and other defined protection system metrics provide the guiding metrics to proceed with concept developments. After a downselect to four primary methods, the concepts were analyzed for dosage severity and the amount of shielding mass necessary to bring dosage to acceptable values. Besides analytical assessments, subscale models of several concepts and one full scale concept demonstrator were created. FY12 work terminated with a plan to demonstrate test articles of two selected approaches. The process of arriving at these selections and their current envisioned implementation are presented in this paper.

Cerro, Jeffrey A

2013-01-01

392

Exploring Venus  

NASA Technical Reports Server (NTRS)

With a temperature higher than the inside of your oven and atmospheric pressure equal to that a kilometer under the ocean, the surface of Venus is one of the most hostile environments in the solar system, and Venus exploration presents a challenge to technology. This lecture presents mission trade-offs and discusses a proposed mission concept for rover and aircraft based exploration of the surface and atmosphere of Venus. Several approaches to the technology, electronics, mechanical parts, and power systems, are discussed.

Landis, Geoffrey A.

2008-01-01

393

Mid-IR Spectra Herbig Ae/Be Stars  

NASA Technical Reports Server (NTRS)

Herbig Ae/Be stars are intermediate mass pre-main sequence stars, the higher mass analogues to the T Tauri stars. Because of their higher mass, they are expected form more rapidly than the T Tauri stars. Whether the Herbig Ae/Be stars accrete only from collapsing infalling envelopes or whether accrete through geometrically flattened viscous accretion disks is of current debate. When the Herbig Ae/Be stars reach the main sequence they form a class called Vega-like stars which are known from their IR excesses to have debris disks, such as the famous beta Pictoris. The evolutionary scenario between the pre-main sequence Herbig Ae/Be stars and the main sequence Vega-like stars is not yet revealed and it bears on the possibility of the presence of Habitable Zone planets around the A stars. Photometric studies of Herbig Ae/Be stars have revealed that most are variable in the optical, and a subset of stars show non-periodic drops of about 2 magnitudes. These drops in visible light are accompanied by changes in their colors: at first the starlight becomes reddened, and then it becomes bluer, the polarization goes from less than 0.1 % to roughly 1% during these minima. The theory postulated by V. Grinnin is that large cometary bodies on highly eccentric orbits occult the star on their way to being sublimed, for systems that are viewed edge-on. This theory is one of several controversial theories about the nature of Herbig Ae/Be stars. A 5 year mid-IR spectrophotometric monitoring campaign was begun by Wooden and Butner in 1992 to look for correlations between the variations in visible photometry and mid-IR dust emission features. Generally the approximately 20 stars that have been observed by the NASA Ames HIFOGS spectrometer have been steady at 10 microns. There are a handful, however, that have shown variable mid-IR spectra, with 2 showing variations in both the continuum and features anti-correlated with visual photometry, and 3 showing variations in the emission features only while the continuum level remained unchanged. The first 2 stars mentioned probably have reprocessing envelopes. The other 3 stars gives important clues to the controversy over the geometry of the gas and dust around these pre-main sequence stars: the steady underlying 10 microns continuum and variable features indicates that an optically thick continuum probably arising from an accretion disk is decoupled from the optically thin emission features which may arise in a disk atmosphere. Bernadette Rodgers has joined this monitoring campaign in the near-IR using GRIMII with the goal of detecting variations in the hot dust continuum and the gas density in the dense accretion region close to these stars.

Wooden, Diane; Witteborn, Fred C. (Technical Monitor)

1997-01-01

394

Building on 50 Years of Systems Engineering Experience for a New Era of Space Exploration  

NASA Technical Reports Server (NTRS)

Over the past 50 years, the National Aeronautics and Space Administration (NASA) has delivered space transportation solutions for America's complex missions, ranging from scientific payloads that expand knowledge, such as the Hubble Space Telescope, to astronauts and lunar rovers destined for voyages to the Moon. Currently, the venerable Space Shuttle, which has been in service since 1981, provides the United States (US) capability for both crew and heavy cargo to low-Earth orbit to construct the International Space Station, before the Shuttle is retired in 2010. In the next decade, NASA will replace this system with a duo of launch vehicles: the Ares I crew launch vehicle and the Ares V cargo launch vehicle. The goals for this new system include increased safety and reliability coupled with lower operations costs that promote sustainable space exploration for decades to come. The Ares I will loft the Orion crew exploration vehicle, while the heavy-lift Ares V will carry the Altair lunar lander, as well as the equipment and supplies needed to construct a lunar outpost for a new generation of human and robotic space pioneers. NASA's Marshall Space Flight Center manages the Shuttle's propulsion elements and is managing the design and development of the Ares rockets, along with a host of other engineering assignments in the field of scientific space exploration. Specifically, the Marshall Center's Engineering Directorate houses the skilled workforce and unique facilities needed to build capable systems upon the foundation laid by the Mercury, Gemini, Apollo, and Shuttle programs. This paper will provide details of the in-house systems engineering and vehicle integration work now being performed for the Ares I and planned for the Ares V. It will give an overview of the Ares I system-level testing activities, such as the ground vibration testing that will be conducted in the Marshall Center's Dynamic Test Stand to verify the integrated vehicle stack's structural integrity and to validate computer modeling and simulation, as well as the main propulsion test article analysis to be conducted in the Static Test Stand. Ultimately, fielding a robust space transportation solution that will carry international explorers and essential payloads will pave the way for a new era of scientific discovery now dawning beyond planet Earth.

Dumbacher, Daniel L.; Lyles, Garry M.; McConnaughey, Paul K.

2008-01-01

395

Europa Jupiter System Mission (EJSM): Exploration Of The Jovian System And Its Icy Satellites  

Microsoft Academic Search

The Europa Jupiter System Mission (EJSM) would be an international mission with the overall theme of investigating the emergence of habitable worlds around gas giants. Its goals are to (1) Determine whether the Jupiter system harbors habitable worlds and (2) Characterize the processes that are operating within the Jupiter system. NASA and ESA have concluded a detailed joint study of

Olivier Grasset; R. Pappalardo; R. Greeley; M. Blanc; M. Dougherty; E. Bunce; J. Lebreton; L. Prockter; D. Senske

2009-01-01

396

Integrated Design for Marketing and Manufacturing team: An examination of LA-ICP-AES in a mobile configuration. Final report  

SciTech Connect

The Department of Energy (DOE) has identified the need for field-deployable elemental analysis devices that are safer, faster, and less expensive than the fixed laboratory procedures now used to screen hazardous waste sites. As a response to this need, the Technology Integration Program (TIP) created a mobile, field-deployable laser ablation-inductively coupled plasma-atomic emission spectrometry (LA-ICP-AES) sampling and analysis prototype. Although the elemental. screening prototype has been successfully field-tested, continued marketing and technical development efforts are required to transfer LA-ICP-AES technology to the commercial sector. TIP established and supported a student research and design group called the Integrated Design for Marketing and Manufacturing (IDMM) team to advance the technology transfer of mobile, field-deployable LA-ICP-AES. The IDMM team developed a conceptual design (which is detailed in this report) for a mobile, field-deployable LA-ICP-AES sampling and analysis system, and reports the following findings: Mobile, field-deployable LA-ICP-AES is commercially viable. Eventual regulatory acceptance of field-deployable LA-ICP-AES, while not a simple process, is likely. Further refinement of certain processes and components of LA-ICP-AES will enhance the device`s sensitivity and accuracy.

Not Available

1994-05-01

397

Discovering the 50 Years of Solar System Exploration: Sharing Your Science with the Public  

NASA Astrophysics Data System (ADS)

The Year of the Solar System (YSS) offers ways for scientists to bring NASA’s science discoveries to their audiences! YSS and the continuing salute to the 50-year history of solar system exploration provide an integrated picture of our new understanding of the solar system for educators and the general public. During the last five decades, NASA has launched a variety of robotic spacecraft to study our solar system. Over that time, our understanding of planets has been revolutionized, as has the technology that has made these discoveries possible.Looking forward, the numerous ongoing and future robotic missions are returning new discoveries of our solar system at an unprecedented rate. YSS combines the discoveries of past NASA planetary missions with the most recent findings of the ongoing missions and connects them to related topics based on the big questions of planetary science, including solar system formation, volcanism, ice, and possible life elsewhere. Planetary scientists are encouraged to get involved in YSS in a variety of ways: - Give a talk at a local museum, planetarium, library, or school to share YSS and your research - Partner with a local educational institution to organize a night sky viewing or mission milestone community event - Work with a classroom teacher to explore one of the topics with students - Connect with a planetary science E/PO professional to identify ways to participate, like creating podcasts,vodcasts, or contributing to monthly topics - Share your ideas for events and activities with the planetaryE/PO community to identify partners and pathways for distribution - And more! Promotional and educational materials, updates, a calendar of activities, and a space to share experiences are available at NASA’s Solar System website: http://solarsystem.nasa.gov/yss. This is an exciting time in planetary sciences as we learn about New Worlds and make New Discoveries!

Buxner, Sanlyn; Dalton, H.; Shipp, S.; Shupla, C.; Halligan, E.; Boonstra, D.; Wessen, A.; Baerg, G.; Davis, P.; Burdick, A.; Zimmerman Brachman, R.

2012-10-01

398

NASA's Evolutionary Xenon Thruster: The NEXT Ion Propulsion System for Solar System Exploration  

NASA Technical Reports Server (NTRS)

This viewgraph presentation reviews NASA s Evolutionary Xenon Thruster (NEXT) Ion Propulsion system. The NEXT project is developing a solar electric ion propulsion system. The NEXT project is advancing the capability of ion propulsion to meet NASA robotic science mission needs. The NEXT system is planned to significantly improve performance over the state of the art electric propulsion systems, such as NASA Solar Electric Propulsion Technology Application Readiness (NSTAR). The status of NEXT development is reviewed, including information on the NEXT Thruster, the power processing unit, the propellant management system (PMS), the digital control interface unit, and the gimbal. Block diagrams NEXT system are presented. Also a review of the lessons learned from the Dawn and NSTAR systems is provided. In summary the NEXT project activities through 2007 have brought next-generation ion propulsion technology to a sufficient maturity level.

Pencil, Eric J.; Benson, Scott W.

2008-01-01

399

Exploration of Chlamydial Type III Secretion System Reconstitution in Escherichia coli  

PubMed Central

Background Type III secretion system is a virulent factor for many pathogens, and is thought to play multiple roles in the development cycle and pathogenesis of chlamydia, an important human pathogen. However, due to the obligate intracellular parasitical nature of chlamydiae and a lack of convenient genetic methodology for the organisms, very limited approaches are available to study the chlamydial type III secretion system. In this study, we explored the reconstitution of a chlamydial type III secretion in Escherichia coli. Results We successfully cloned all 6 genomic DNA clusters of the chlamydial type III secretion system into three bacterial plasmids. 5 of the 6 clusters were found to direct mRNA synthesis from their own promoters in Escherichia coli transformed with the three plasmids. Cluster 5 failed to express mRNA using its own promoters. However, fusion of cluster 5 to cluster 6 resulted in the expression of cluster 5 mRNA. Although only two of the type III secretion system proteins were detected transformed E. coli due to limited antibody availability, type III secretion system-like structures were detected in ultrathin sections in a small proportion of transformed E. coli. Conclusions We have successfully generated E. coli expressing all genes of the chlamydial type III secretion system. This serves as a foundation for optimal expression and assembly of the recombinant chlamydial type III secretion system, which may be extremely useful for the characterization of the chlamydial type III secretion system and for studying its role in chlamydial pathogenicity.

Bao, Xiaofeng; Beatty, Wandy L.; Fan, Huizhou

2012-01-01

400

The development of the human exploration demonstration project (HEDP), a planetary systems testbed  

NASA Technical Reports Server (NTRS)

The Human Exploration Demonstration Project (HEDP) is an ongoing task at the National Aeronautics and Space Administration's Ames Research Center to address the advanced technology requirements necessary to implement an integrated working and living environment for a planetary surface habitat. The integrated environment will consist of life support systems, physiological monitoring of project crew, a virtual environment workstation, and centralized data acquisition and habitat systems health monitoring. There will be several robotic systems on a simulated planetary landscape external to the habitat environment to provide representative work loads for the crew. This paper describes the status of the HEDP after one year, the major facilities composing the HEDP, the project's role as an Ames Research Center testbed, and the types of demonstration scenarios that will be run to showcase the technologies.

Chevers, Edward S.; Korsmeyer, David J.

1993-01-01

401

Overview of Potable Water Systems on Spacecraft Vehicles and Applications for the Crew Exploration Vehicle (CEV)  

NASA Technical Reports Server (NTRS)

Providing water necessary to maintain life support has been accomplished in spacecraft vehicles for over forty years. This paper will investigate how previous U.S. space vehicles provided potable water. The water source for the spacecraft, biocide used to preserve the water on-orbit, water stowage methodology, materials, pumping mechanisms, on-orbit water requirements, and water temperature requirements will be discussed. Where available, the hardware used to provide the water and the general function of that hardware will also be detailed. The Crew Exploration Vehicle (CEV or Orion) water systems will be generically discussed to provide a glimpse of how similar they are to water systems in previous vehicles. Conclusions on strategies that could be used for CEV based on previous spacecraft water systems will be made in the form of questions and recommendations.

Peterson, Laurie J.; Callahan, Michael R.

2007-01-01

402

A multitasking behavioral control system for the Robotic All Terrain Lunar Exploration Rover (RATLER)  

NASA Technical Reports Server (NTRS)

An alternative methodology for designing an autonomous navigation and control system is discussed. This generalized hybrid system is based on a less sequential and less anthropomorphic approach than that used in the more traditional artificial intelligence (AI) technique. The architecture is designed to allow both synchronous and asynchronous operations between various behavior modules. This is accomplished by intertask communications channels which implement each behavior module and each interconnection node as a stand-alone task. The proposed design architecture allows for construction of hybrid systems which employ both subsumption and traditional AI techniques as well as providing for a teleoperator's interface. Implementation of the architecture is planned for the prototype Robotic All Terrain Lunar Explorer Rover (RATLER) which is described briefly.

Klarer, P.

1994-01-01

403

Earth Exploration Toolbook Chapter : Using GLOBE Data to Study the Earth System  

NSDL National Science Digital Library

This Earth Exploration Toolbook chapter guides users through the process of locating and graphing data that has been collected by students who participate in the GLOBE Program. Users access the online GLOBE graphing tool and produce a graph comparing four Earth system variables over two complete years. Data include Maximum Air Temperature, Soil Moisture (at depths of both 10 cm and 90 cm), and Rainfall recorded in Greenville, Pennsylvania. As they investigate this specific case study, users discover patterns in the data that reveal seasonal changes in soil moisture. The patterns provide opportunities to discuss such Earth system concepts as the reservoir, the flux or flow of moisture between different reservoirs, and the role of solar energy in driving Earth system processes.

Haddad, Nick

2004-01-01

404

Highly Survivable Avionics Systems for Long-Term Deep Space Exploration  

NASA Technical Reports Server (NTRS)

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

405

PARIS: A new class of missions to explore the Trojan asteroids and outer solar system  

NASA Astrophysics Data System (ADS)

The Jovian Trojan asteroids were highlighted by the recent National Academy of Sciences Decadal Study (2002) as important primitive body targets. The Decadal Study recognized that primitive bodies are the principal building blocks of the solar system, and summarized fundamental science questions relating to them, including their range of sizes, compositions, physical characteristics, locations, processes of formation and alteration, and their role in planet formation and evolution. Exploration of the Jovian Trojans can be accomplished at reasonable cost using PARIS (Planetary Access with Radioisotope Ion-drive System) spacecraft, which enable a new class of missions to the outer solar system. These low-thrust missions launched to a high C3 are especially effective for exploring objects in a shallow gravity wells. The PARIS spacecraft take advantage of the high-efficiency of Stirling radioisotope generators (SRGs) to provide the power for an electric propulsion system. The net power-to-mass ratio enables New-Frontiers class missions to carry a significant science payload to the outer solar system. A PARIS mission could reach the Trojan asteroids in less than 5 years using the next generation SRGs with a demonstrated efficiency of >30% and a projected specific power of >8W/kg. With the specific power of current first generation SRGs, the flight time would be increased by about 20%. The power system would generate about 900 W and the launch mass would be slightly less than 1000 kg. We consider a mission that would orbit the largest Jovian Trojan, 624 Hektor, and then go on to orbit at least one other nearby object of the estimated 105 Trojans greater than 1 km in diameter. A candidate payload for such a mission would include wide-field and narrow-field cameras, an UV-Vis-IR spectrograph, gamma-ray and neutron spectrometers, and plasma and energetic particle spectrometers.

Prockter, L. M.; Gold, R. E.; McNutt, R. L.; Ostdiek, P. H.; Ensworth, C. B.

2005-08-01

406

Fracture Analysis Based on Quantitative Evaluation of Microcracking in Ceramics Using AE Source Characterization  

NASA Astrophysics Data System (ADS)

Quantitative detection of microcracks during fracture process of alumina was carried out by AE source characterization, which enables the quantitative characterization of the size, nucleation velocity and fracture mode, as well as nucleation time and location of individual microcracks. Fracture toughness tests of SENB specimens of two types of alumina with different grain size and purity were carried out in air and water. AE signals emitted from microcrackings were detected by piezoelectric transducers. The combined response function of the specimen and measurement system was experimentally determined using a pencil lead breaking as a simulated source. Then AE source function which describes the nature of microcrack nucleation was determined by the inverse calculation using obtained response function and detected signal. Consequently, it was clarified that the size of microcrack in water was larger than that in air for both alumina and larger microcracks nucleated in water resulted in the degradation of fracture resistance.

Wakayama, Shuichi; Ishiwata, Kohei

407

Integrated Software Systems for Crew Management During Extravehicular Activity in Planetary Terrain Exploration  

NASA Technical Reports Server (NTRS)

Initial planetary explorations with the Apollo program had a veritable ground support army monitoring the safety and health of the 12 astronauts who performed lunar surface extravehicular activities (EVAs). Given the distances involved, this will not be possible on Mars. A spacesuit for Mars must be smart enough to replace that army. The next generation suits can do so using 2 software systems serving as virtual companions, LEGACI (Life support, Explor