Note: This page contains sample records for the topic exploration systems aes from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: November 12, 2013.
1

15 CFR 758.2 - Automated Export System (AES).  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Automated Export System (AES). 758.2 Section 758.2 Commerce... § 758.2 Automated Export System (AES). The Census Bureau's Foreign...electronically using the Automated Export System (AES). In order to use AES, you must...

2013-01-01

2

22 CFR 120.30 - The Automated Export System (AES).  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false The Automated Export System (AES). 120.30 Section 120.30 Foreign Relations...DEFINITIONS § 120.30 The Automated Export System (AES). The Automated Export System (AES) is the Department of Commerce, Bureau of...

2013-04-01

3

15 CFR 758.1 - The Shipper's Export Declaration (SED) or Automated Export System (AES) record.  

Code of Federal Regulations, 2010 CFR

...Declaration (SED) or Automated Export System (AES) record. 758.1 Section 758.1...Declaration (SED) or Automated Export System (AES) record. (a) The Shipper's Export...Declaration (SED) or Automated Export System (AES) record. The SED (Form...

2010-01-01

4

15 CFR 758.1 - The Shipper's Export Declaration (SED) or Automated Export System (AES) record.  

Code of Federal Regulations, 2010 CFR

...Declaration (SED) or Automated Export System (AES) record. 758.1 Section 758.1...Declaration (SED) or Automated Export System (AES) record. (a) The Shipper's Export...Declaration (SED) or Automated Export System (AES) record. The SED (Form...

2009-01-01

5

Secret data communication system using steganography, AES and RSA  

Microsoft Academic Search

The paper introduces a new secret data communication system that employs the usage of two state-of-the art cryptographic algorithms (RSA with asymmetric keys and AES with symmetric key) together with steganography. The joining of these three techniques builds a robust steganography-based communication system capable of withstanding multiple types of attacks, detection and reverse engineering. Our system was designed in a

Septimiu Fabian Mare; Mircea Vladutiu; Lucian Prodan

2011-01-01

6

Exploration EVA System.  

National Technical Information Service (NTIS)

In January 2004, the President announced a new Vision for Space Exploration. NASA's Office of Exploration Systems has identified Extravehicular Activity (EVA) as a critical capability for supporting the Vision for Space Exploration. EVA is required for al...

L. Kearney

2004-01-01

7

MULTICORE IMPLEMENTATION OF THE AES ALGORITHM IN THE MEASUREMENT SYSTEM  

Microsoft Academic Search

The paper presents the implementation of the Advanced Encryption Algorithm (AES) in the measurement system, where the virtual instruments equipped with the multi-core processors are used. The encryption algorithm is first presented, then its modification to take advantage over the multi-core processor is described. Implementation of the latter in the virtual instrument working under the Real-Time (RT) mode is presented.

Piotr Bilski; W. Winiecki

8

NASA: Solar System Exploration  

NSDL National Science Digital Library

NASA's Solar System Exploration website offers a wealth of information about the objects in our solar system, recent technology used to explore these worlds, space missions, and stories about the people behind the missions. Users will find image galleries, multimedia resources for teachers and learners, videos, animations, and other interactive features to explore the planets, comets, asteroids, the history of robotic exploration, and future missions.

2005-05-10

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

Unbelievable Security. Matching AES Security Using Public Key Systems  

Microsoft Academic Search

The Advanced Encryption Standard (AES) provides three levels of security: 128, 192, and 256 bits. Given a desired level of security for the AES, this paper discusses matching public key sizes for RSA and the ElGamal family of protocols. For the latter both traditional multi- plicative groups of nite elds and elliptic curve groups are considered. The practicality of the

Arjen K. Lenstra

2001-01-01

11

Acoustic emission structural health management systems (AE-SHMS)  

NASA Astrophysics Data System (ADS)

Many of today's methods of inspecting structures are very time consuming, labor intensive and in many cases (due to limited access), impractical. In addition, long shutdown times are required to perform the inspections, thus creating tremendous expenses associated with manpower, materials and lost production. With continuing advances in signal processing and communications a significant interest has been shown in developing new diagnostic technologies for monitoring the integrity of structures with known defects, or for detecting new defects, in real time with minimum human involvement. The continued use of aging structures, especially in regard to the airworthiness of aging aircraft, is a major area of concern. Recent developments in both active and passive Acoustic Emission monitoring as an advanced tool for 'Structural Health Management Systems (SHMS),' are illustrated by using two recently developed acoustic emission systems; the Acoustic Emission-Health and Usage Monitoring System (AE-HUMS) helicopter drivetrain health monitoring system, and the Acoustic Emission Flight Instrument System (AEFIS) composite health monitoring system. The data collected with these types of systems is processed with advanced data screening and classification techniques, which are employed to take full advantage of parametric and waveform-based acoustic emission.

Finlayson, Richard D.; Friesel, Mark A.; Carlos, Mark F.; Miller, Ronnie; Godinez, Valery

2000-05-01

12

Solar system exploration  

Microsoft Academic Search

Two fundamental goals lie at the heart of U.S. solar system exploration efforts: first, to characterize the evolution of the solar system; second, to understand the processes which produced life. Progress in planetary science is traced from Newton's definition of the principles of gravitation through a variety of NASA planetary probes in orbit, on other planets and traveling beyond the

Geoffrey A. Briggs; William L. Quaide

1986-01-01

13

Solar Tides in the Upper Equatorial Thermosphere: A Comparison between AE-E (Atmosphere Explorer-E Satellite) Data and the NCAR Thermospheric General Circulation Model.  

National Technical Information Service (NTIS)

Numerical calculations of the equatorial thermospheric tidal temperatures and densities are compared with mass spectrometer data from the Atmosphere Explorer-E Satellite (AE-E) for solar minimum solstice conditions. The model calculations were made using ...

M. F. Storz

1987-01-01

14

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

15

Solar system exploration  

NASA Astrophysics Data System (ADS)

Two fundamental goals lie at the heart of U.S. solar system exploration efforts: first, to characterize the evolution of the solar system; second, to understand the processes which produced life. Progress in planetary science is traced from Newton's definition of the principles of gravitation through a variety of NASA planetary probes in orbit, on other planets and traveling beyond the solar system. It is noted that most of the planetary data collected by space probes are always eventually applied to improving the understanding of the earth, moon, Venus and Mars, the planets of greatest interest to humans. Significant data gathered by the Mariner, Viking, Apollo, Pioneer, and Voyager spacecraft are summarized, along with the required mission support capabilities and mission profiles. Proposed and planned future missions to Jupiter, Saturn, Titan, the asteroids and for a comet rendzvous are described.

Briggs, Geoffrey A.; Quaide, William L.

16

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

17

Seismic exploration system  

Microsoft Academic Search

Seismic exploration method in arctic regions involving the generation of a seismic disturbance in the water beneath the ice in areas where conventional marine and land exploration methods are functionally inadequate. Seismic disturbances are generated by an air gun assembly which automatically executes lowering air guns through apertures in the ice and retrieving them while carrying out preventive measures against

Arlton H. White

1983-01-01

18

Data mining based full ceramic bearing fault diagnostic system using AE sensors.  

PubMed

Full ceramic bearings are considered the first step toward full ceramic, oil-free engines in the future. No research on full ceramic bearing fault diagnostics using acoustic emission (AE) sensors has been reported. Unlike their steel counterparts, signal processing methods to extract effective AE fault characteristic features and fault diagnostic systems for full ceramic bearings have not been developed. In this paper, a data mining based full ceramic bearing diagnostic system using AE based condition indicators (CIs) is presented. The system utilizes a new signal processing method based on Hilbert Huang transform to extract AE fault features for the computation of CIs. These CIs are used to build a data mining based fault classifier using a k-nearest neighbor algorithm. Seeded fault tests on full ceramic bearing outer race, inner race, balls, and cage are conducted on a bearing diagnostic test rig and AE burst data are collected. The effectiveness of the developed fault diagnostic system is validated using real full ceramic bearing seeded fault test data. PMID:21990335

He, David; Li, Ruoyu; Zhu, Junda; Zade, Mikhail

2011-10-10

19

Solar System Exploration  

NSDL National Science Digital Library

This resource focuses on NASA's interplanetary exploration and discovery missions. The site features links to topics that include news, the planets, missions (current and past), science and technology, a multimedia gallery of images and animations, NASA employees, a kids' section, and education and history sections.

20

NASA Solar System Exploration Website  

Microsoft Academic Search

The NASA Solar System Exploration website, http:\\/\\/solarsystem.nasa.gov, sponsored by the Science Director for Solar System Exploration, Office of Space Science, NASA, is a gateway to information about our solar system and NASA's missions and research to understand it. The site has been designed for easy navigation and is becoming known as a resource for educators, students, media, and publishers. Major

A. M. Sohus

2000-01-01

21

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

22

NASA Solar System Exploration Website  

NASA Astrophysics Data System (ADS)

The NASA Solar System Exploration website, http://solarsystem.nasa.gov, sponsored by the Science Director for Solar System Exploration, Office of Space Science, NASA, is a gateway to information about our solar system and NASA's missions and research to understand it. The site has been designed for easy navigation and is becoming known as a resource for educators, students, media, and publishers. Major subsections include latest news, newest images, a link to NASA research opportunities in space science, technology, missions, information on solar system bodies, the people who are involved in solar system exploration, and the history of solar system exploration in the space age. There is also a link to the NASA Solar System Exploration Education and Public Outreach Forum. Members of the planetary science community are invited to contribute suggestions, comments, and content to the website, including links to their own institutions and research.

Sohus, A. M.

2000-10-01

23

Solar System exploration Road Map  

Microsoft Academic Search

NASA has commissioned a group of scientists, engineers, educators and technologists to prepare a ``Road Map'' for Solar System exploration which covers the next 15-20 years. This Road Map is expected to serve as a guide for the continuation of Solar System exploration and future space science activities supported by NASA. The Road Map is currently in draft form, however,

Jurgen Rahe; Samuel Gulkis

1997-01-01

24

Implementing an appointment-based system in A&E to ensure appropriate use of services.  

PubMed

This article describes how an appointment-based system was introduced at an ophthalmic A&E department, and why it was felt necessary to implement this change. The changes have prevented needless trips to the unit and patient feedback has been positive. PMID:19736799

Tillotson, Julie

25

Biospheres and Solar System Exploration.  

National Technical Information Service (NTIS)

The implications of biosphere technology is briefly examined. The exploration status and prospects of each world in the solar system is briefly reviewed, including the asteroid belt, the moon, and comets. Five program elements are listed as particularly c...

T. O. Paine

1990-01-01

26

Rapid prototyping of AES encryption for wireless communication system on FPGA  

Microsoft Academic Search

This paper proposes a wireless communication system for secure transmission of data. Bluetooth is used as the wireless communication medium due to its low-cost and low-power consumption features. Advanced encryption standard (AES) protocol is implemented for the security reason over Bluetooth stack. RC10 prototyping board with Xilinx XC3S1500L-4-FG320 device has been used for the hardware evaluation of the system design.

Anurag Gupta; Afandi Ahmad; Mhd Saeed Sharif; Abbes Amira

2011-01-01

27

Phase stability in the systems AeAl(2-x)Mgx (Ae = Ca, Sr, Ba): electron concentration and size controlled variations on the laves phase structural theme.  

PubMed

The systems AeAl(2-x)Mgx (Ae = Ca, Sr, Ba) display electron concentration induced Laves phase structural changes. However, the complete sequence MgCu2 --> MgNi2 --> MgZn2 with increasing x (decreasing electron count) is only observed for Ae = Ca. Compounds SrAl(2-x)Mgx (0 < x < or = 2) and BaAl(2-x)Mgx (x = 0.85 and 2.0) were synthesized and structurally characterized by X-ray diffraction experiments. For the Sr system the structural sequence CeCu2 --> MgNi2 --> MgZn2 occurs with increasing Mg content x. Thus, larger Sr does not allow the realization of the MgCu2 structure at low x. For Ae = Ba a binary compound BaAl2 does not exist, but more Ba-rich Ba7Al13 forms. The reinvestigation of the crystal structure of Ba7Al13 by selected area and convergent beam electron diffraction in a transmission electron microscope revealed a superstructure, which subsequently could be refined from single X-ray diffraction data. The formula unit of the superstructure is Ba21Al40 (space group P31m, Z = 1, a = 10.568(1) angstroms, c = 17.205(6) angstroms). In Ba21Al40 a size match problem between Ba and Al present in Ba7Al13 is resolved. The structure of Ba7Al13 (Ba21Al40) can be considered as a Ba excess variant of the hexagonal MgNi2 Laves phase type structure. An incommensurately modulated variant of the MgNi2 structure is obtained for phases BaAl(2-x)Mgx with x = 0.8-1. At even higher Mg concentrations a structural change to the proper MgZn2 type structure takes place. PMID:15257605

Amerioun, Shahrad; Yokosawa, Tadahiro; Lidin, Sven; Hussermann, Ulrich

2004-07-26

28

OPPORTUNITIES IN SOLAR SYSTEM EXPLORATION  

Microsoft Academic Search

NASA's Office of Space Science launches several space missions a year and is always looking for technology development that will enable return of new and interesting data. The Division of Solar System Exploration has several technology development programs that solicit proposals for new or improved instruments, including thermal detectors. The Planetary Instrument Definition and Development Program solicits ideas for low

Susan M. Niebur

29

Packaging of AeDNVGFP Transducing Virus by Expression of Densovirus Structural Proteins from a Sindbis Virus Expression System  

Microsoft Academic Search

Genetic recombination resulting in the production of wild-type infectious virus is an obstacle in the current system for producing densovirus transducing particles. In order to eliminate this problem, a double subgenomic Sindbis virus (TE\\/3?2J\\/VP) was engineered that expresses the structural proteins (VPs) ofAedesdensonucleosis virus (AeDNV) from the second subgenomic promoter. Expression of AeDNV VPs from TE\\/3?2J\\/VP was confirmed by Northern

Tanya M. Allen-Miura; Boris N. Afanasiev; Kenneth E. Olson; Barry J. Beaty; Jonathan O. Carlson

1999-01-01

30

Manganese Nodule Exploration System Manganknollen - Explorationssystem.  

National Technical Information Service (NTIS)

Different tools for manganese nodule exploration are thoroughly investigated. Certain tools are selected applying technical and economical criteria. Three optimized exploration systems are designed as examples. (Author)

G. Braun H. Ristow H. Weichart

1973-01-01

31

Power systems for space exploration  

SciTech Connect

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

Shipbaugh, C.; Solomon, K.A.

1992-01-01

32

AE 941.  

PubMed

AE 941 [Arthrovas, Neoretna, Psovascar] is shark cartilage extract that inhibits angiogenesis. AE 941 acts by blocking the two main pathways that contribute to the process of angiogenesis, matrix metalloproteases and the vascular endothelial growth factor signalling pathway. When initial development of AE 941 was being conducted, AEterna assigned the various indications different trademarks. Neovastat was used for oncology, Psovascar was used for dermatology, Neoretna was used for ophthalmology and Arthrovas was used for rheumatology. However, it is unclear if these trademarks will be used in the future and AEterna appears to only be using the Neovastat trademark in its current publications regardless of the indication. AEterna Laboratories signed commercialisation agreements with Grupo Ferrer Internacional SA of Spain and Medac GmbH of Germany in February 2001. Under the terms of the agreement, AEterna has granted exclusive commercialisation and distribution rights to AE 941 in oncology to Grupo Ferrer Internacional for the Southern European countries of France, Belgium, Spain, Greece, Portugal and Italy. It also has rights in Central and South America. Medac GmbH will have marketing rights in Germany, the UK, Scandinavia, Switzerland, Austria, Ireland, the Netherlands and Eastern Europe. In October 2002, AEterna Laboratories announced that it had signed an agreement with Australian healthcare products and services company Mayne Group for marketing AE 941 (as Neovastat) in Australia, New Zealand, Canada and Mexico. In March 2003, AEterna Laboratories announced it has signed an agreement with Korean based LG Life Sciences Ltd for marketing AE 941 (as Neovastat) in South Korea. The agreement provides AEterna with upfront and milestone payments, as well as a return on manufacturing and sales of AE 941. AEterna Laboratories had granted Alcon Laboratories an exclusive worldwide licence for AE 941 for ophthalmic products. However, this licence has been terminated. In 1999, AEterna secured funding for AE 941, part of which is from Technology Partnerships Canada (TPC), a research support programme run by Canada's federal government. Industry Canada will contribute $Can 1 for every $Can3 spent by AEterna on the development of AE 941, up to a total figure of $Can29.4 million. AEterna will reimburse TPC upon commercialisation of AE 941-derived products as a royalty on income generated. In January 2004 AEterna announced that development of AE 941 would be focusing on non-small cell lung cancer and that development for renal cell carcinoma would be discontinued. AEterna had previously announced in January 2003, following its acquisition of Zentaris, that development of AE 941 would be "strictly focused" on renal and non-small cell lung cancer, suggesting that development for all other indications has been discontinued, at least for the foreseeable future. PMID:15293867

2004-01-01

33

Solar System Exploration, 1995-2000.  

National Technical Information Service (NTIS)

Goals for planetary exploration during the next decade include: (1) determining how our solar system formed and understanding whether planetary systems are a common phenomenon through out the cosmos; (2) exploring the diverse changes that planets have und...

D. Black G. Varsi J. Veverka L. Soderblom S. Squyres

1994-01-01

34

Exploring the Physical, Chemical and Thermal Characteristics of a New Potentially Insensitive High Explosive: RX-55-AE-5  

SciTech Connect

Current work at the Energetic Materials Center, EMC, at Lawrence Livermore National Laboratory (LLNL) includes both understanding properties of old explosives and measuring properties of new ones [1]. The necessity to know and understand the properties of energetic materials is driven by the need to improve performance and enhance stability to various stimuli, such as thermal, friction and impact insult. This review will concentrate on the physical properties of RX-55-AE-5, which is formulated from heterocyclic explosive, 2,6-diamino-3,5-dinitropyrazine-1-oxide, LLM-105, and 2.5% Viton A. Differential scanning calorimetry (DSC) was used to measure a specific heat capacity, C{sub p}, of {approx} 0.950 J/g{center_dot} C and a thermal conductivity, {kappa}, of {approx} 0.475 W/m{center_dot} C. The LLNL kinetics modeling code Kinetics05 and the Advanced Kinetics and Technology Solutions (AKTS) code Thermokinetics were both used to calculate Arrhenius kinetics for decomposition of LLM-105. Both obtained an activation energy barrier E {approx} 180 kJ mol{sup -1} for mass loss in an open pan. Thermal mechanical analysis, TMA, was used to measure the coefficient of thermal expansion (CTE). The CTE for this formulation was calculated to be {approx} 61 {micro}m/m{center_dot} C. Impact, spark, friction are also reported.

Weese, R K; Burnham, A K; Turner, H C; Tran, T D

2006-06-05

35

The golden age of solar system exploration  

Microsoft Academic Search

The origin and evolution of the NASA program of solar system exploration of the past two decades are discussed. The past and possible future roles of national prestige, vision, knowledge and applications as the motivations for the United States space exploration program are examined. The origin of the technology and scientific basis for space exploration by the United States is

N. W. Hinners

1981-01-01

36

NASA Solar System Exploration: Galileo  

NSDL National Science Digital Library

This site contains details on the Galileo spacecraft mission to Jupiter. Galileo operated from 1989-2003 and sent back valuable information about Jupiter and its moons before being destroyed in Jupiter's atmosphere. Information on the mission, photos, explorations, news articles, and educational links are available.

Harvey, Samantha

2003-10-10

37

Future exploration of the outer solar system  

Microsoft Academic Search

Exploration of the outer solar system is constrained by vast distances, consequent communications and light time limitations, power, and long flight times. Early reconnaissance missions (Pioneer 10 and 11, Voyager 1 and 2) employed relatively fast trajectories resulting in very fast fly-bys. The next generation of exploration (Galileo and Cassini) has been characterized by spacecraft with large propellant systems and

T. Johnson

2004-01-01

38

Solar System Exploration, 1995-2000  

Microsoft Academic Search

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

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

1994-01-01

39

A coordinated campaign of the intermediate polar AE aqr. 1: The system parameters  

NASA Astrophysics Data System (ADS)

We report intermediate resolution spectroscopy (50 km/s) of the magnetic Cataclysmic Variable AE Aqr performed as part of the World Astronomy Days (WAD) campaign. Our analysis of the absorption features supports a K4 classification for the companion star, which contributes more than 95% of the total flux in the range 600-700 nm. We find that the companion star fills its Roche lobe since we detect a 10% modulation in the rotational broadening (V sin i) of the absorption fines, due to the changing geometry. Model fitting to the V sin i(phi) curve enables us to measure directly the system inclination (i = 58 +/- 6 deg) and the gravity darkening coefficient (beta = 0.08 +/- 0.01). Improved orbital parameters are also presented, including an updated mass ratio (q = K1/K2 = 0.630 +/- 0.012) based upon our K2 value and the spin-pulse delay. An independent determination of q is also provided by correcting the phase-averaged V sin i for non-spherical effects. The need for these two values to agree constrain the limb-darkening coefficient to be epsilon approximately equal to 0.40 (for beta = 0.08). The component masses derived from our values of K2, q and i are M1 = 0.79 +/- 0.16 solar mass units and M2 = 0.50 +/- 0.10 solar mass units. In addition, we do not see spectral evidence of irradiation effects.

Casares, J.; Mouchet, M.; Martinez-Pais, I. G.; Harlaftis, E. T.

1996-09-01

40

Galileo: exploration of Jupiter's system  

SciTech Connect

The scientific objectives of the Galileo mission to the Jovian system is presented. Topics discussed include the history of the project, our current knowledge of the system, the objectives of interrelated experiments, mission design, spacecraft, and instruments. The management, scientists, and major contractors for the project are also given.

Johnson, T.V.; Yeates, C.M.; Colin, L.; Fanale, F.P.; Frank, L.; Hunten, D.M.

1985-06-01

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

Power systems for space exploration  

Microsoft Academic Search

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

Calvin Shipbaugh; Kenneth A. Solomon

1992-01-01

43

Network analysis for exploring systems biology  

Microsoft Academic Search

Life is one of the most complex phenomena in the universe. To understand complex biological systems, it requires the integration of experimental and computational research - in other words a systems biology approach. Many theoretical methods and models exist for exploring systems biology including well-known examples such as statistical inference, graph analysis, network inference, and dynamic modeling. These systems play

Xuning Chen; Weiping Zhu

2010-01-01

44

Exploration-sampling drilling system  

SciTech Connect

A mobile, exploration mineral sample drilling rig is described comprising a mobile carrier, a drill mast mounted on the mobile carrier, drill mast mounting means adjustably mounting the drill mast on the carrier whereby sample holes may be drilled at various positions around the carrier and at various angles, and a drill head mounted by the drill mast: the drill mast comprising a drill head frame, a mast support frame connected to the upper and bottom portions of the drill head frame and positioning the drill head frame outwardly from the carrier, the drill mast mounting means being operably-connected to and extending inwardly of the mast support frame; the drill bead frame comprising a pair of side beams, an upper cross beam connecting the upper portions of the side beams, a generally V-shaped lower cross beam connecting the lower portions of the side beams with its apex oriented downward, the lower cross beam having an opening there through; the drill head being so constructed and arranged that it is slidably mounted to and between the drill head frame side beams to define a drill string axis as extending longitudinally of the drill head frame side beams, between the planes formed by the inner and outer faces of the drill head frame side beams, and through the lower cross beam opening; the mast support frame being so constructed and arranged that it is positioned inwardly from the drill head frame a sufficient distance that the drill head and any apparatus or piping or hosing associated therewith may traverse the drill head frame side beams free of interference from the mast support frame and its connections to the drill head frame; the drill mast mounting means including trunnion means slidably mounting the mast support means whereby the drill mast may be moved upwardly and downwardly relative to the trunnion means, being so constructed and arranged to provide a pivot axis about which the drill mast may be rotated relative to the trunnion means.

Heller, M.H.

1993-05-25

45

Indonesian petroleum systems and exploration efficiency  

SciTech Connect

The Republic of Indonesia has over 40 productive petroleum systems and more than 100 speculative petroleum systems. Since the first oil discoveries in the 1880's, cumulative discovered ultimately recoverable petroleum resources in Indonesia have reached 50 billion barrels of oil equivalent. There are eight principal producing areas and nearly 1,000 oil and gas fields. Most of these resources have been found in the last 50 years. Successful exploration continues; at least two discoveries per year are made which exceed 50 million barrels of oil equivalent reserves. Productive petroleum system source types are split almost equally between marine and deltaic-lacustrine facies. The majority of source rocks are Tertiary in age; Mesozoic source rocks are restricted to Eastern Indonesia. Discovery process analysis indicates generally high exploration efficiency in Indonesia. An upwardly convex discovery process curve typifies many systems, reflecting both exploration efficiency and maturity; this pattern is well displayed in areas such as Central Sumatra and Salawati. A much more random or straight line process curve, as seen in West Natuna, occurs where more complex petroleum systems have inhibited exploration efficiency. An inverted, or concave upward curve, seen in some Java petroleum systems, is probably economically driven, related to development of domestic Indonesian gas markets. Several curves, such as those for the North Sumatra:Bampo-Peutu and East Kalimantan:Tanjung systems are dominated by single fields. Different exploration phases can be recognized in many systems, each phase having its own specific exploration statistics.

Howes, J.V.C.; Tisnawijaya, S. (Atlantic Richfield Indonesia, Inc., Jakarta (Indonesia))

1996-01-01

46

76 FR 1427 - AES Wind Generation, Inc. v. California Independent System Operator Corporation; Notice of...  

Federal Register 2010, 2011, 2012, 2013

...Shortening Date for Filing Answers to Motion for Stay January 3, 2011. Take notice...Included in the complaint filing was a Motion for Stay of the date by which AES Wind...notice, the date for filing answers to the Motion for Stay is shortened to and...

2011-01-10

47

External Resource: Solar System Exploration: Missions  

NSDL National Science Digital Library

This NASA webpage, Solar System Exploration, allows students to search missions by name, decade, nation, target, mission, and status. Topics: arial, atmospheric, flybys, impact, lander, orbiter, rover, Deep Space Network

1900-01-01

48

Design Space Exploration for The Beamformer System  

Microsoft Academic Search

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

Daniel D. Gajski; Smita Bakshi

1993-01-01

49

Local Food Systems: Explorative Findings from Finland  

Microsoft Academic Search

Local Food Systems: Explorative Findings from Finland. In this paper we look at local food systems as alternatives to conventional food supply chains. Supporting alternative food systems at the local level is a way to promote the viability of rural areas and create and sustain local food strategies. The objective of the paper is to increase our understanding of local

Sari FORSMAN; Jaana PAANANEN

50

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  

SciTech Connect

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 included diamond core drilling, borescope observations, and detailed engineering geological mapping in Consolidation Coal's McElroy coal mine in West Virginia. The field investigations were accompanied by regional geology studies involving aerial photography and lineament analysis as well as by laboratory testing of 103 rock and coal samples. The roof conditions were interpreted by means of an engineering rock mass classification system, known as the Geomechanics Classification. It was found that the roof quality in the areas mined by the AES machine was poor and that the action of the AES support beams could be detrimental to the overall roof stability. Improvements in the procedures for evaluating future AES-type mining are suggested.

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

1980-07-01

51

Solar System Exploration, 1995-2000  

NASA Astrophysics Data System (ADS)

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.

1994-09-01

52

Solar System Exploration: Paper Models for Kids  

NSDL National Science Digital Library

NASA offers this website focusing on Solar System Exploration and projects for kids to build paper versions of the "super tough robots are out there exploring our solar system." Using colored, cut and folded pieces of paper, kids can construct models of Cassini, Galileo and many other spacecrafts. Along with the instructions (which need to be downloaded and printed), they provide a rating for level of difficulty as well as information on the spacecraft and its mission. A link to a website devoted to paper modeling provides some basic tips on paper model construction.

53

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

54

Optics for future solar system exploration  

Microsoft Academic Search

The optics technology necessary for future solar system exploration is discussed. To satisfy the various mission objectives, optical components need to be of low weight, provide adequate spatial resolution and mapping coverage, provide necessary spectral resolution, provide means to perform adaptable mapping spectrometry, operate under low light levels, provide color images of high fidelity and operate under high temperatures. Future

D. D. Norris; F. E. Vescelus; J. B. Wellman

1980-01-01

55

Future exploration of the outer solar system  

NASA Astrophysics Data System (ADS)

Exploration of the outer solar system is constrained by vast distances, consequent communications and light time limitations, power, and long flight times. Early reconnaissance missions (Pioneer 10 and 11, Voyager 1 and 2) employed relatively fast trajectories resulting in very fast fly-bys. The next generation of exploration (Galileo and Cassini) has been characterized by spacecraft with large propellant systems and relatively slow (gravity assist) trajectories needed energetically to achieve orbit around Jupiter and Saturn. All of these spacecraft utilized radioisotope thermoelectric generators for reliable, but modest power. Future exploration priorities require highly capable spacecraft systems that go into orbit around the primary planet and then perform multiple tasks (e.g. orbiting individual moons and delivering surface and atmospheric scientific probes). To achieve major scientific advances will require significant increases in communication rates, improved instrumentation and high power available for experiments. Fission-powered nuclear electric propulsion is being studied to meet these requirements. A Jupiter Icy Moons Orbiter is proposed as the first of this class of new, highly capable missions. The paper will review the scientific rationale for the JIMO mission and prospects for applying these techniques to exploration of Saturn and the other outer planets.

Johnson, T.

56

19 CFR 192.11 - Description of the AES.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 2009-04-01 false Description of the AES. 192.11 Section 192.11 Customs Duties...Information Through the Automated Export System (AES) § 192.11 Description of the AES. AES is a voluntary program that allows...

2009-04-01

57

19 CFR 192.11 - Description of the AES.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Description of the AES. 192.11 Section 192.11 Customs Duties...Information Through the Automated Export System (AES) § 192.11 Description of the AES. AES is a voluntary program that allows...

2013-04-01

58

19 CFR 192.11 - Description of the AES.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Description of the AES. 192.11 Section 192.11 Customs Duties...Information Through the Automated Export System (AES) § 192.11 Description of the AES. AES is a voluntary program that allows...

2010-04-01

59

The human exploration of the solar system  

NASA Astrophysics Data System (ADS)

In this paper we propose a detailed program plan for the human exploration of the solar system. This thrust is clearly the next step in the long history of human exploration of the unknown. The program proposed here contemplates a return to the Moon by 1995. The principal purpose of the return mission is to look for water that might be used to fuel subsequent missions to Mars and to other planets in the solar system. Alternative program plans are developed in detail for the first trip to the planet Mars in case water is found on the Moon (Case A) and in case it is not found as well (Case B). In both cases, the first trip to Mars would be made in the year 2003. The total run-out cost of the proposed program is between $90 billion (Case B) and $125 billion (Case A) for the next fourteen years.

Bell, Lisa; Bilby, Curt; Boyd, John W.; Davis, George; Korsmeyer, David; Mark, Hans; McCuster, Todd; O'Connor, Brendan; Pinon, Elfego; Frizzell, Andrew

60

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.

61

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

62

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; Prez-Mercader, Juan; Parro Garca, Victor

2001-08-01

63

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.

64

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

65

Fabrication of a high performance acoustic emission (AE) sensor to monitor and diagnose disturbances in HTS tapes and magnet systems  

Microsoft Academic Search

An acoustic emission (AE) technique was introduced as a non-destructive method to monitor sudden deformation caused by local\\u000a heat concentrations and micro-cracks within superconductors and superconducting magnets. However, the detection of AE signals\\u000a in a high temperature superconductor (HTS) tape is not easy because of its low signal to noise ratio caused by the noise from\\u000a boiling liquid cryogen or

Ju-Hyung Kim; Jung-Bin Song; Young Hun Jeong; Young-Jin Lee; Jong-Hoo Paik; Woo-Seok Kim; Haigun Lee

2010-01-01

66

An atmospheric visual analysis and exploration system.  

PubMed

Meteorological research involves the analysis of multi-field, multi-scale, and multi-source data sets. In order to better understand these data sets, models and measurements at different resolutions must be analyzed. Unfortunately, traditional atmospheric visualization systems only provide tools to view a limited number of variables and small segments of the data. These tools are often restricted to two-dimensional contour or vector plots or three-dimensional isosurfaces. The meteorologist must mentally synthesize the data from multiple plots to glean the information needed to produce a coherent picture of the weather phenomenon of interest. In order to provide better tools to meteorologists and reduce system limitations, we have designed an integrated atmospheric visual analysis and exploration system for interactive analysis of weather data sets. Our system allows for the integrated visualization of 1D, 2D, and 3D atmospheric data sets in common meteorological grid structures and utilizes a variety of rendering techniques. These tools provide meteorologists with new abilities to analyze their data and answer questions on regions of interest, ranging from physics-based atmospheric rendering to illustrative rendering containing particles and glyphs. In this paper, we will discuss the use and performance of our visual analysis for two important meteorological applications. The first application is warm rain formation in small cumulus clouds. Here, our three-dimensional, interactive visualization of modeled drop trajectories within spatially correlated fields from a cloud simulation has provided researchers with new insight. Our second application is improving and validating severe storm models, specifically the Weather Research and Forecasting (WRF) model. This is done through correlative visualization of WRF model and experimental Doppler storm data. PMID:17080847

Song, Yuyan; Ye, Jing; Svakhine, Nikolai; Lasher-Trapp, Sonia; Baldwin, Mike; Ebert, David S

67

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.

68

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

69

KS-121A Camera System for the RF5A\\/E aircraft  

Microsoft Academic Search

To satisfy current reconnaissance trends, high resolution, small format cameras are becoming more necessary. The KS-121A Camera System is representative of this trend. Developed to improve the reconnaissance capability of the RF-5 aircraft, the KS-121A 70-mm Frame Camera System offers high resolution in a small format. The small size permits the mounting of four cameras in the aircraft nose which

O. J. Smith

1975-01-01

70

Automated Estimating System (AES): Version 2.0, User's Manual: Phase 2.  

National Technical Information Service (NTIS)

This document describes Version 2.0 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 Marti...

D. A. Holder R. L. Schwarz

1987-01-01

71

[Application of ICP-AES in automotive hydraulic power steering system fault diagnosis].  

PubMed

The authors studied the innovative applications of the inductively coupled plasma-atomic emission spectrometry in automotive hydraulic power steering system fault diagnosis. After having determined Fe, Cu and Al content in the four groups of Buick Regal 2.4 main metal power-steering fluid whose travel course was respectively 2-9 thousand kilometers, 11-18 thousand kilometers, 22-29 thousandkilometers, and 31-40 thousand kilometers, and the database of primary metal content in the Buick Regal 2.4 different mileage power-steering fluid was established. The research discovered that the main metal content increased with increasing mileage and its normal level is between the two trend lines. Determination of the power-steering fluid main metal content and comparison with its database value can not only judge the wear condition of the automotive hydraulic power steering system and maintain timely to avoid the traffic accident, but also help the automobile detection and maintenance personnel to diagnose failure reasons without disintegration. This reduced vehicle maintenance costs, and improved service quality. PMID:23586258

Chen, Li-Dan

2013-01-01

72

Nuclear Power System Evolution: MARS Robotics Outposts to Human Exploration  

Microsoft Academic Search

NASA has been studying various architectures to explore Mars encompassing sample return; robotic outpost with extended range exploration and possibly leading to eventual human exploration missions. The more demanding missions with longer-range mobility, enhanced surface operations, high rate communications, propellant production, deep drilling at multiple sites, etc., will require larger and more robust power systems beyond the current capability of

Robert L. Cataldo

2002-01-01

73

ADVANCED RADIOISOTOPE HEAT SOURCE AND PROPULSION SYSTEMS FOR PLANETARY EXPLORATION  

Microsoft Academic Search

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

R. C. OBrien; S. D. Howe; J. E. Werner

2010-01-01

74

DFA on AES  

Microsoft Academic Search

In this paper we describe two different DFA attacks on the AES. The first one uses a theoretical fault model that induces a fault on only one bit of an intermediate result, hence allowing us to obtain the key by using 50 faulty ciphertexts for an AES-128. The second attack uses a more realistic fault model: we assume that we

Christophe Giraud

2004-01-01

75

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

76

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

77

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

78

Exploring Ice in the Solar System  

NSDL National Science Digital Library

This module includes several lessons aimed at introducing ice science to students. In the first activity, students share personal ice experience stories through drawing, telling, and writing. This enables the teacher to diagnose personal conceptions about ice. Then students explore a big block of ice. They ask and record their questions and start an ice science notebook. Depending on the nature of the questions, the teacher selects appropriate follow-up activities. Other lessons include: Ice Melts,Ice Floats,Ice Flows, Ice is a Mineral, Life in Icy Places, and Ice in Space. Each lesson includes a kinesthetic activity where students mime and act out ice science concepts, creating a science performance laboratory. These experiences lay the foundation for deeper conceptual understanding in later school years. All lessons include extensive background information, a list of national standards addressed, suggested curriculum extensions, a list of resources and photo gallery.

2005-11-01

79

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

80

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

81

Intelligent system for exploring dynamic crisis environments  

Microsoft Academic Search

The routing in complex buildings is provided by inf ormation systems. But during a crisis situation, th ese systems may collapse due to certain incidents like an explo sion, a fire or sabotage. The task of guiding peopl e in this situation has to be handled in some way. In this pa per we present a possible solution to this

Bogdan Tatomir; Leon Rothkrantz; Mirela Popa

82

19 CFR 192.12 - Criteria for denial of applications requesting AES post-departure (Option 4) filing status...  

Code of Federal Regulations, 2010 CFR

...Criteria for denial of applications requesting AES post-departure (Option 4) filing status...Information Through the Automated Export System (AES) § 192.12 Criteria for denial of applications requesting AES post-departure (Option 4) filing...

2010-04-01

83

19 CFR 192.12 - Criteria for denial of applications requesting AES post-departure (Option 4) filing status...  

Code of Federal Regulations, 2010 CFR

...Criteria for denial of applications requesting AES post-departure (Option 4) filing status...Information Through the Automated Export System (AES) § 192.12 Criteria for denial of applications requesting AES post-departure (Option 4) filing...

2009-04-01

84

19 CFR 192.13 - Revocation of participants' AES post-departure (Option 4) filing privileges; appeal procedures.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Revocation of participants' AES post-departure (Option 4) filing privileges...Information Through the Automated Export System (AES) § 192.13 Revocation of participants' AES post-departure (Option 4) filing...

2013-04-01

85

19 CFR 192.13 - Revocation of participants' AES post-departure (Option 4) filing privileges; appeal procedures.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 false Revocation of participants' AES post-departure (Option 4) filing privileges...Information Through the Automated Export System (AES) § 192.13 Revocation of participants' AES post-departure (Option 4) filing...

2009-04-01

86

19 CFR 192.13 - Revocation of participants' AES post-departure (Option 4) filing privileges; appeal procedures.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Revocation of participants' AES post-departure (Option 4) filing privileges...Information Through the Automated Export System (AES) § 192.13 Revocation of participants' AES post-departure (Option 4) filing...

2010-04-01

87

19 CFR 192.12 - Criteria for denial of applications requesting AES post-departure (Option 4) filing status...  

Code of Federal Regulations, 2013 CFR

...Criteria for denial of applications requesting AES post-departure (Option 4) filing status...Information Through the Automated Export System (AES) § 192.12 Criteria for denial of applications requesting AES post-departure (Option 4) filing...

2013-04-01

88

Chaotic appearance of the AE index  

Microsoft Academic Search

A typical time sequence of AE shows no obvious regularities which suggests either that the magnetosphere is a random (stochastic) system or displays deterministic chaos. To find out whether the magnetosphere is random or chaotic, AE data have been studied by the embedding dimension method to find the correlation dimension of the magnetosphere. The autocorrelation (AC) time scale (AC()=½AC(0)) is

P. Hansen; C. K. Goertz; R. A. Smith

1991-01-01

89

Drilling Systems for Extraterrestrial Subsurface Exploration  

Microsoft Academic Search

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

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

2008-01-01

90

Product service systems: exploring operational practices  

Microsoft Academic Search

Increasingly, original equipment manufacturers (OEMs) are offering integrated solutions of products and services (product service systems (PSS)). To be successful in a service strategy, the OEM has to be able to provide services at a lower cost than the do-it-yourself alternative of the customer. We identify five service operations guidelines to achieve operational excellence in the field of PSS. The

P. J. Colen; M. R. Lambrecht

2012-01-01

91

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

92

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

93

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

94

Power system requirements and selection for the Space Exploration Initiative  

NASA Astrophysics Data System (ADS)

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

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

1991-09-01

95

Exploring student response systems in nursing education.  

PubMed

Using software products in the classroom can be an effective component in an overall technology integration plan. Choosing the right software for the subject area and classroom, however, can be a formidable task if undertaken without preplanning. In this article, we describe the developing process experienced professionally and personally with the student response system. The Internet and other new digital technologies have changed the way we respond to information. These changes are making an impact on students' learning styles and preferences. How to address this issue might be found in an endeavor that places the student at the center of the learning process and facilitates a more active experience: the interactive student response system. Imagine classrooms where teachers electronically introduce assignments using receivers and students beam information from pocket-sized remote controls. Imagine students working on group projects exchanging information without pen or paper. PMID:18769181

Zurmehly, Joyce; Leadingham, Camille

96

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

97

An Atmospheric Visual Analysis and Exploration System  

Microsoft Academic Search

Meteorological research involves the analysis of multi-field, multi-scale, and multi-source data sets. Unfortunately, traditional atmospheric visualization systems only provide tools to view a limited number of variables and small segments of the data. These tools are often restricted to 2D contour or vector plots or 3D isosurfaces. The meteorologist must mentally synthesize the data from multiple plots to glean the

Yuyan Song; Jing Ye; Nikolai A. Svakhine; Sonia Lasher-trapp; Mike Baldwin; David S. Ebert

2006-01-01

98

NASA Solar System Exploration: Galileo Images  

NSDL National Science Digital Library

During its 14-year odyssey, the NASA spacecraft Galileo took thousands of images. In addition to extensively photographing the Jovian system, Galileo also turned its cameras on asteroids, Venus, Earth, and its Moon. Galileo also captured the only direct view of comet Shoemaker-Levy 9 fragments smashing into Jupiter in July 1994. This image gallery is separated by the various planets and moons visited by Galileo (Jupiter, Io, Europa, Ganymede, Callisto, Earth & Moon, Venus, Asteroids, and Comet Shoemaker-Levy 9) as well as the geographical and atmospheric features of the visited objects (Atmospheric Haze, Topography, Volcanic Features, Aurora, Great Red Spot, Lightning, White Ovals) and collected data from its instruments (Hot Spots, Temperature Data, and Cloud Height Data). It provides a wealth of images for either the casual viewer or the instructor seeking images that display particular phenomena.

99

Colliding Beam Fusion Electric Power System for Mars Exploration  

NASA Astrophysics Data System (ADS)

Exploration of Mars, by robotic means and eventually manned exploration, will require significant levels of reliable, high-density electric power. An electric power system based on fusion energy possesses distinct advantages. If developed successfully fusion energy sources would be characterized by high fuel energy density, low system mass, modest fuel requirements, and the abundance of fuel sources throughout the Solar System. NASA plans a FY01 new program start with a goal of realizing a fully operational fusion space propulsion system within 20 years; a similar time frame as envisioned for the MARS Exploration Initiative. The development milestones for a planetary-based power system and space propulsion system are synergistic extensions of our existing efforts to develop an Earth-based energy source. This paper reviews the scientific and technology base for our design and describes options for the use of this technology on a Mars mission.

O'Toole, Joseph A.; Wessel, Frank J.; Rostoker, N.; Binderbauer, M.

2000-07-01

100

An exploration of service system operation architecture reconfiguration modeling  

Microsoft Academic Search

On the foundation of analyzing and comparing the literature of service system, service product, service innovation and mass customization thought, we explored the service system architecture modeling based on the reconfiguration technique. Through object-oriented definition, proposed the architecture model frame combining the state representation structure with dynamic operation structure of service system, researched the plug and play manner of the

Wang Bo; Li Congdong

2010-01-01

101

Exploring Open Software System Acquisition Processes and Architectures  

Microsoft Academic Search

Abstract This study explores and develops concepts leading to the combination of best practices from open source software development (OSSD) projects with emerging capabilities for virtual system acquisition Virtual system acquisition is an evolving approach to demonstrate significant improvements in reducing the cost and cycle time for acquiring software - intensive systems, while improving their quality It employs techniques and

Walt Scacchi

102

High-Resolution Studies of Gas and Dust around Young Intermediate-Mass Stars. II. Observations of an Additional Sample of Herbig AE Systems  

NASA Astrophysics Data System (ADS)

In an earlier paper (Mannings & Sargent; Paper I), we presented evidence for disks of gas and dust associated with seven Herbig Ae stars, based on high-resolution interferometric millimeter-wave observations of continuum and molecular line emission. These systems are simultaneously high-mass analogs of the approximately solar-mass T Tauri stars and the evolutionary precursors of the prototypical main-sequence debris-disk sources ? Pic, ? Lyr, and ? PsA. Here we extend the original survey to include four additional Herbig Ae systems. We have also imaged two of the sources from Paper I at higher resolution. The new data are presented and analyzed, and are combined with the results from the earlier sample in order to address the properties of this class of circumstellar disk. Derived disk masses are indistinguishable from the masses of T Tauri disks. Although the combined sample is small, it seems likely that disk masses are essentially uncorrelated with stellar mass for pre-main-sequence stars of spectral type A0 and later.

Mannings, Vincent; Sargent, Anneila I.

2000-01-01

103

Explore  

NSDL National Science Digital Library

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

2002-01-01

104

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

105

Nanotube-based Sensors and Systems for Outer Planetary Exploration  

NASA Astrophysics Data System (ADS)

Direct sensing and processing at the nanometer scale offer NASA the opportunity to expand its capabilities in deep space exploration, particularly for the search for signatures of life, the analysis of planetary oceans and atmospheres, and communications systems. Carbon nanotubes, with their unique mechanical, electrical, and radiation-tolerant properties, are a promising tool for this exploration. We are developing devices based on carbon nanotubes, including sensors, actuators, and oscillators. Additional information is contained in the original extended abstract.

Noca, F.; Hunt, B. D.; Hoenk, M. E.; Choi, D.; Kowalczyk, R.; Williams, R.; Xu, J.; Koumoutsakos, P.

2001-01-01

106

Exploring \\  

Microsoft Academic Search

The power density in high performance systems continues to rise with every process technology generation, thereby increasing the operating temperature and creating 'hot spots' on the die. As a result, the performance, reliability and power consumption of the system degrade. To avoid these 'hot spots', 'temperature-aware' design has become a must. For low-power embedded systems though, it is not clear

Giacomo Paci; Paul Marchal; Francesco Poletti; Luca Benini

2006-01-01

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 practical value of health management in space exploration systems  

Microsoft Academic Search

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

William Kahle; Jim Miller

2005-01-01

109

UWB Tracking System Design for Lunar/Mars Exploration.  

National Technical Information Service (NTIS)

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...

C. Phan D. Arndt J. Gross J. Ni P. Ngo

2006-01-01

110

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

111

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

112

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

113

PRIMITIVE BODY EXPLORATION IN THE SOLAR SYSTEM AND ASTROBIOLOGY  

Microsoft Academic Search

Origins of planetary systems and life are common goals among astronomers, biologists and planetary scientists. In the context of planetary exploration, astrobiology can be defined an interdisciplinary subject which answers fp, ne and fl parameters for the Drake-Sagan equation. The new concept of habitable zones also demands better understanding of primitive bodies of the solar system while \\

Hajime YANO

2002-01-01

114

Explore  

NSDL National Science Digital Library

Created "to champion the selfless acts of others" and "to create a portal into the soul of humanity" the Explore website was created in part with support from the Annenberg Foundation. On this website, visitors can view films that cover themes such as animal rights, poverty, the environment, and spirituality. Clicking on the "Films" tab brings up a grid of recently added films, complete with another section that divides them up by "Places" and Causes". The films range in length from a two to thirty minutes, and visitors can also create their own playlist of films for their own use. Some of the more recently added films of note include "Fish Out of Water" and "Gorillas 98.6% Human". Also, visitors can connect with other parties by using the "Discussions" section to talk about travel, philanthropy, or filmmaking. The "Minds" area features profiles of the filmmakers and others profiled throughout the site, and visitors can filter them by countries and causes.

115

Intelligent systems for the autonomous exploration of Titan and Enceladus  

NASA Astrophysics Data System (ADS)

Future planetary exploration of the outer satellites of the Solar System will require higher levels of onboard automation, including autonomous determination of sites where the probability of significant scientific findings is highest. Generally, the level of needed automation is heavily influenced by the distance between Earth and the robotic explorer(s) (e.g. spacecraft(s), rover(s), and balloon(s)). Therefore, planning missions to the outer satellites mandates the analysis, design and integration within the mission architecture of semi- and/or completely autonomous intelligence systems. Such systems should (1) include software packages that enable fully automated and comprehensive identification, characterization, and quantification of feature information within an operational region with subsequent target prioritization and selection for close-up reexamination; and (2) integrate existing information with acquired, "in transit" spatial and temporal sensor data to automatically perform intelligent planetary reconnaissance, which includes identification of sites with the highest potential to yield significant geological and astrobiological information. In this paper we review and compare some of the available Artificial Intelligence (AI) schemes and their adaptation to the problem of designing expert systems for onboard-based, autonomous science to be performed in the course of outer satellites exploration. More specifically, the fuzzy-logic framework proposed is analyzed in some details to show the effectiveness of such a scheme when applied to the problem of designing expert systems capable of identifying and further exploring regions on Titan and/or Enceladus that have the highest potential to yield evidence for past or present life. Based on available information (e.g., Cassini data), the current knowledge and understanding of Titan and Enceladus environments is evaluated to define a path for the design of a fuzzy-based system capable of reasoning over collected data and capable of providing the inference required to autonomously optimize future outer satellites explorations.

Furfaro, Roberto; Lunine, Jonathan I.; Kargel, Jeffrey S.; Fink, Wolfgang

2008-05-01

116

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

117

Pipe Explorer{sup {trademark}} system. Innovative technology summary report  

SciTech Connect

The Pipe Explorer{trademark} system, developed by Science and Engineering Associates, Inc. (SEA), under contract with the U.S. Department of Energy (DOE) Morgantown Energy Technology Center, has been used to transport various characterizing sensors into piping systems that have been radiologically contaminated. DOE`s nuclear facility decommissioning program must characterize radiological contamination inside piping systems before the pipe can be recycled, remediated, or disposed. Historically, this has been attempted using hand-held survey instrumentation, surveying only the accessible exterior portions of pipe systems. Various measuring difficulties, and in some cases, the inability to measure threshold surface contamination values and worker exposure, and physical access constraints have limited the effectiveness of traditional survey approaches. The Pipe Explorer{trademark} system provides a viable alternative.

NONE

1996-04-01

118

The progress of exploring extra-solar planetary systems  

NASA Astrophysics Data System (ADS)

With the advance of the space exploring, the study of the extra-solar planetary systems becomes an interesting topic since such system may exist the life or even the modern civilization. In this paper we give a brief introduction on the discovery of extra-solar planetary systems, and discuss the feasibility of detection techniques and methods developed in recent years. In particular, we present detailed interpretations of the results by the radial velocity method. With the launch of some specific small satellites, we can predict the discovery of a large number of candidates of the extra-solar planetary systems. We can expect that the exploring of extra-solar planetary systems will have a prospective era in the near future.

Liu, Yu-Juan; Zhao, Gang

2005-09-01

119

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

120

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

121

The submillimeter properties of AE Aqr  

NASA Astrophysics Data System (ADS)

AE Aqr is a cataclysmic variable consisting of a magnetised white dwarf with a spin period of 33 s, and a K-dwarf companion. Because of the rapid spin the magnetosphere of the white dwarf the matter that is flowing over from the secondary cannot accrete onto the white dwarf, and rather it is ejected from the system. AE Aqr is subject to extended flaring activity at all wavelengths from radio via optical to X-rays. I present observations of AE Aqr at 345 and 850 GHz using the LABOCA and SABOCA bolometers on APEX. These observations are good enough to distinguish individual flares at both 345 and 850 GHz, and the SABOCA observation is the first measurement of the system at 850 GHz.

Torkelsson, Ulf

2013-02-01

122

Exploring strategic approaches towards a sustainable transport system  

Microsoft Academic Search

This paper undertakes a 'backcasting' analysis exploring strategic approaches for overall systems sustainability in personal transport. Starting from a robust definition of sustainability for the personal transport sector, the research examines the impact of combinations of transport technologies and changes in travel behaviour in reducing CO2 emissions towards a sustainable level. In doing this a simple equation model is used.

Stephen Potter

123

Nuclear thermal propulsion transportation systems for lunar\\/Mars exploration  

Microsoft Academic Search

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,

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

1992-01-01

124

Scientific Assessment of NASA's Solar System Exploration Roadmap.  

National Technical Information Service (NTIS)

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 a...

1996-01-01

125

Improving exploration with geographical information system (GIS) technology  

Microsoft Academic Search

Timely reliable access to data is required by Earth Scientists and Engineers evaluating geology, facilities, environment, and new business opportunities. Geographical Information System (GIS) technology has been recently implemented to provide efficient and comprehensive access to data for exploration work in Venezuela. The GIS allows rapid comparisons, queries, sorting, and evaluation of data that in the past required multiple hardware

P. B. Goodwin; M. R. Choiniere; F. W. Harris

1996-01-01

126

Advances in Autonomous Systems for Missions of Space Exploration  

Microsoft Academic Search

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

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

2002-01-01

127

Modular Antenna Pointing System for the Explorer Platform Satellite.  

National Technical Information Service (NTIS)

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 co...

J. Andrus E. Korzeniowski

1992-01-01

128

Future steps in the exploration of the Solar System  

Microsoft Academic Search

The last ten years have been characterized by a renewed worldwide effort of exploration of the Solar System, which has produced spectacular new data and concluded the ``discovery'' phase. The next decades will focus on refinement of knowledge and will tackle specific problems such as the boundary conditions for the onset and maintenance of life on planetary bodies. Final understanding

M. Coradini

2006-01-01

129

An inertial fusion propulsion scheme for solar system exploration  

SciTech Connect

A novel fusion scheme that combines the favorable aspects of both inertial and magnetic confinement approaches is analyzed as a propulsion device for potential utilization in solar system exploration. Using an appropriate set of equations for the plasma dynamics and the magnetic nozzle, we assess the system's propulsive capability by applying the results to a round trip mission to Mars. We find that such a device would allow a massive vehicle to make the journey in less than five months.

Kammash, T.; Galbraith, D.L. (Department of Nuclear Engineering, The University of Michigan, Ann Arbor, Michigan 48109 (US))

1991-01-05

130

The Future of Solar System Exploration (2003-2013) -- Community Contributions to the NRC Solar System Exploration Decadal Survey  

Microsoft Academic Search

Between June 2001 and January 2002, planetary scientists from around the United States and other nations created 24 self-selected panels to discuss issues facing solar system exploration in 2003-2013 and how those issues should be addressed. Each panel generated a white paper, containing their conclusions and recommendations. These were forwarded to the National Research Council as community input in support

Mark V. Sykes

2002-01-01

131

Future NASA Solar System Exploration Activities: A Framework for International Cooperation.  

National Technical Information Service (NTIS)

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 primar...

B. M. French T. Ramlose G. A. Briggs

1992-01-01

132

2004: the Old Continent explores the Solar System  

NASA Astrophysics Data System (ADS)

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 probes, like the Cassini-Huygens that, put on an interplanetary trajectory due to the gravitational pull of the various planet it encounters, will reach Saturn and its moon Titan to study it in detail. New technology tests are developed for the SMART and Rosetta missions that are searching for the origins of the Solar System by reaching a few asteroids and landing on a comet to spy its content. At last I will touch upon our next future: the Venus surface that will be explored by Venus express.

Fulchignoni, M.

133

Nuclear thermal propulsion transportation systems for lunar/Mars exploration  

NASA Astrophysics Data System (ADS)

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.

1992-09-01

134

Unmanned systems to support the human exploration of Mars  

NASA Astrophysics Data System (ADS)

Robots and other unmanned systems will play many critical roles in support of a human presence on Mars, including surveying candidate landing sites, locating ice and mineral resources, establishing power and other infrastructure, performing construction tasks, and transporting equipment and supplies. Many of these systems will require much more strength and power than exploration rovers. The presence of humans on Mars will permit proactive maintenance and repair, and allow teleoperation and operator intervention, supporting multiple dynamic levels of autonomy, so the critical challenges to the use of unmanned systems will occur before humans arrive on Mars. Nevertheless, installed communications and navigation infrastructure should be able to support structured and/or repetitive operations (such as excavation, drilling, or construction) within a "familiar" area with an acceptable level of remote operator intervention. This paper discusses some of the factors involved in developing and deploying unmanned systems to make humans' time on Mars safer and more productive, efficient, and enjoyable.

Gage, Douglas W.

2010-04-01

135

NASA'S RPS Design Reference Mission Set for Solar System Exploration  

NASA Astrophysics Data System (ADS)

NASA's 2006 Solar System Exploration (SSE) Strategic Roadmap identified a set of proposed large Flagship, medium New Frontiers and small Discovery class missions, addressing key exploration objectives. These objectives respond to the recommendations by the National Research Council (NRC), reported in the SSE Decadal Survey. The SSE Roadmap is down-selected from an over-subscribed set of missions, called the SSE Design Reference Mission (DRM) set Missions in the Flagship and New Frontiers classes can consider Radioisotope Power Systems (RPSs), while small Discovery class missions are not permitted to use them, due to cost constraints. In line with the SSE DRM set and the SSE Roadmap missions, the RPS DRM set represents a set of missions, which can be enabled or enhanced by RPS technologies. At present, NASA has proposed the development of two new types of RPSs. These are the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG), with static power conversion; and the Stirling Radioisotope Generator (SRG), with dynamic conversion. Advanced RPSs, under consideration for possible development, aim to increase specific power levels. In effect, this would either increase electric power generation for the same amount of fuel, or reduce fuel requirements for the same power output, compared to the proposed MMRTG or SRG. Operating environments could also influence the design, such that an RPS on the proposed Titan Explorer would use smaller fins to minimize heat rejection in the extreme cold environment; while the Venus Mobile Explorer long-lived in-situ mission would require the development of a new RPS, in order to tolerate the extreme hot environment, and to simultaneously provide active cooling to the payload and other electric components. This paper discusses NASA's SSE RPS DRM set, in line with the SSE DRM set. It gives a qualitative assessment regarding the impact of various RPS technology and configuration options on potential mission architectures, which could support NASA's RPS technology development planning, and provide an understanding of fuel need trades over the next three decades.

Balint, Tibor S.

2007-01-01

136

Multi-Attribute Tradespace Exploration in Space System Design  

NASA Astrophysics Data System (ADS)

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

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

2002-01-01

137

Lights, camera, A&E.  

PubMed

Channel 4 series 24 Hours in A&E was one of the television highlights of 2011. Filmed at King's College Hospital in London, it showed the reality of life in an A&E department and may have improved the public's understanding of nursing. PMID:22324233

Gould, Mark

138

Expert systems in exploration: can they be cost-effective  

SciTech Connect

PROSPECTOR is the best-known application of an expert system in exploration. Others exist for gamma-ray well logging analysis but are in general company-restricted and not in the open literature. PROSPECTOR, however, is comprised of a large set of elegant subprograms, each designed for a specific goal - generally for hard minerals. The program is expensive, costly to run, and requires a mainframe (usually a LISP machine) for operation. Recently, a microcomputer-based version (u-PROSPECTOR) has become available, but it still follows the formal artificial intelligence (AI) syntax of PROSPECTOR. In the Remote Sensing Laboratory at Stanford, they have been experimenting with low-end ($100-$1000) AI programs. The development of these has been driven by (1) the explosion of availability of microcomputers and (2) the realization by developers that the marketplace has many more Fortran and C-language machines available than the dedicated (and expensive) LISP units. This paper will discuss those commercially available, low-priced AI shells as applied to several of the simplest exploration problems - spectral pattern recognition and texture in radar imagery - and extrapolate their usefulness to more complex decision-making steps in exploration practice.

Lyon, R.P.J.

1987-05-01

139

An inertial fusion propulsion scheme for solar system exploration  

NASA Astrophysics Data System (ADS)

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.

140

Improving exploration with geographical information system (GIS) technology  

SciTech Connect

Timely reliable access to data is required by Earth Scientists and Engineers evaluating geology, facilities, environment, and new business opportunities. Geographical Information System (GIS) technology has been recently implemented to provide efficient and comprehensive access to data for exploration work in Venezuela. The GIS allows rapid comparisons, queries, sorting, and evaluation of data that in the past required multiple hardware platforms, multiple software packages, paper plots, spreadsheets, and time. A vendor GIS database package formed the foundation. This GIS provided regional coverage for the entire country of Venezuela at a scale of 1:250,000. It included 36,000 wells and associated attributes, facilities, geologic maps, potential field data, and transportation networks. Essential with GIS, all of the data were transformed from multiple cartographic datums to a single map projection. Proprietary and other tabular databases were incorporated into the vendor GIS by Chevron, significantly upgrading the value of the system for company exploration. Tabular databases were either imported, linked or converted to the GIS. They included Nomad, Paradox, Oracle, Openworks, and PC-based spreadsheets containing wells, seismic, and geochemistry data. Nontabular data types incorporated into the GIS included digital outcrop log and paleosections, maps, other GIS data, Global Positioning System control points, satellite imagery and scanned photographs. The enhanced GIS has proven valuable for facilitating access to, and rapid and accurate evaluation of, large geographic areas with multiple data sources and types.

Goodwin, P.B.; Choiniere, M.R.; Harris, F.W. (Chevron Overseas Petroleum, Inc., San Ramon, CA (United States)) (and others)

1996-01-01

141

Evaluation of Externally-Powered Hybrid System: Viennatone Hand, Emg and Switch Control, Hosmer E400 Elbow, AE Prosthesis.  

National Technical Information Service (NTIS)

A prosthetic hybrid system consisting of an above elbow prosthesis containing an externally-powered electromechanical hand and a conventional mechanical elbow was functionally evaluated. Two different means of controlling the terminal device were provided...

J. W. Hodge W. R. Bartels

1970-01-01

142

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

143

Solar System Frontier - Exploring the Heliospheric Interface from 1 AU  

NASA Astrophysics Data System (ADS)

The region where the expanding solar wind meets the surrounding galactic medium remains poorly explored. The structure of and the physical processes at this solar system frontier - the heliospheric interface - are of fundamental importance for understanding the interaction of our star, the Sun, with the galactic medium. This region also needs to be charted for optimizing our first foray into interstellar space by the Interstellar Probe mission and for supporting the truly interstellar exploration of the future. The present concepts of the heliospheric interface are based on scarce and mostly indirect experimental data and limited by the technical difficulties and budgetary realities of sending space probes to this distant region. In addition, the sheer size of the essentially asymmetric heliosphere calls for remote techniques to probe its global three-dimensional properties. We describe two experimental approaches for probing the solar system frontier from 1 AU. Imaging in fluxes of energetic neutral atoms (ENAs) will determine the nature of the termination shock and the properties of the solar plasma in the heliospheric sheath. Then, imaging of the heliosphere in extreme ultraviolet (EUV) will map the heliopause. NASA recently selected a new dedicated space mission to image the heliosphere in ENA fluxes. The efforts in EUV mapping of the heliopause presently focus on development of the mission concept and enabling instrumentation.

Gruntman, M.

144

Numerical exploration of coherent excitation in three-level systems  

SciTech Connect

A great deal of effort has been applied to understanding population dynamics within a variety of coherent excitation schemes. The goal in such studies has been to understand the conditions necessary for efficient transfer of population from one state to another. While many theoretical treatments include the effects of natural lifetimes that are present in any given system, some neglect this important aspect when considering specific cases. Adiabatic approximations are also widely made. Additionally, it is often difficult to envision how the different parameters controlling efficient population transfer are interrelated or even which parameters are the most critical, especially when the decay lifetimes are taken into account. This work describes a numerical study of coherent excitation applied to a {sup 87}Rb ladder system where spontaneous decay rates are included, and adiabaticity is not assumed. A useful method is introduced to explore the interdependence of various excitation parameters. The efficiency of population transfer as a function of several experimentally controllable parameters is explored, and other general trends are summarized.

Camp, H.A.; Shah, M.H.; Trachy, M.L.; Weaver, O.L.; DePaola, B.D. [J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506-2601 (United States)

2005-05-15

145

Exploring the Function of Neural Oscillations in Early Sensory Systems  

PubMed Central

Neuronal oscillations appear throughout the nervous system, in structures as diverse as the cerebral cortex, hippocampus, subcortical nuclei and sense organs. Whether neural rhythms contribute to normal function, are merely epiphenomena, or even interfere with physiological processing are topics of vigorous debate. Sensory pathways are ideal for investigation of oscillatory activity because their inputs can be defined. Thus, we will focus on sensory systems as we ask how neural oscillations arise and how they might encode information about the stimulus. We will highlight recent work in the early visual pathway that shows how oscillations can multiplex different types of signals to increase the amount of information that spike trains encode and transmit. Last, we will describe oscillation-based models of visual processing and explore how they might guide further research.

Koepsell, Kilian; Wang, Xin; Hirsch, Judith A.; Sommer, Friedrich T.

2009-01-01

146

Exploring the Solar System with a Human Orrery  

NASA Astrophysics Data System (ADS)

Astronomy instructors, and those teaching other sciences, are slowly coming to the realization that it's not what the instructor does that matters - it's what the students do for themselves. To foster this approach to learning, the instructor's role is to provide an environment - an engaging task, a target for the students' focus and guidance - in which the students discover the concepts for themselves. With this role in mind, for a large class of undergraduate non-Science majors, we adapted the human orrery designed by the Armagh Observatory in Northern Ireland into one that can be easily built and explored by a class of 30-40 students in a 1-hour tutorial. Students actively and individually explore the scale of the Solar System and the motion of the planets. As the human orrery requires a large, open space, we staged the activity in the foyer of the University library as a public outreach event celebrating IYA2009, generating tremendous enthusiasm and support from students, faculty, library staff and University administration. This work is supported by the Carl Wieman Science Education Initiative at the University of British Columbia.

Newbury, Peter R.; Gendre, M. A.; Gladman, B.; Kasian, L. E.; Meger, N.

2009-05-01

147

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

148

Astrobiology as an Integrating Theme in Solar System Exploration  

NASA Astrophysics Data System (ADS)

The discipline of astrobiology examines (i) the origin and evolution of life on Earth and the detailed interplay between biological and planetary evolution, (ii) the evolution of our solar system and the potential and actual distribution of life within it, (iii) the occurrence of planets around other stars and their potential for life, and (iv) the interplay between each of these areas. In our own solar system, astrobiology encompasses much more than just the search for life on Mars or Europa. Our goal is to understand the nature of planetary habitability--which planets have evolved to have environments that are habitable by microorganisms, and which have not. By understanding the processes that control the architecture of our solar system, we can extrapolate how these same processes might have played out in other planetary systems and what the distribution of habitability might be beyond our own system. In this context, Mars and Europa appear as potentially habitable worlds either today or in the past, Ganymede and Callisto might have deep subsurface oceans and be habitable, Venus might have been habitable early on but does not appear to be today, and Titan probably has had intermittent liquid water as well as ongoing chemical evolution involving organic molecules. Looking more broadly, the origin and the evolution of the gas-giant planets and their dynamical effects have had a major influence on the terrestrial planets; the characteristics of the Kuiper belt and Oort cloud influence our understanding of early chemical and volatile processes that affect habitability; and asteroids have had a tremendous impact on the terrestrial planets throughout their history. In order to understand planetary habitability in general, and the implications of a discovery of the presence or absence of life on any given object, we need to understand the detailed origin and evolution of our solar system as a whole and of the individual bodies within it. A broad program of planetary exploration is the best way to investigate the astrobiology of our solar system.

Jakosky, B. M.

2003-12-01

149

The Exploration of Titan and the Saturnian System  

NASA Astrophysics Data System (ADS)

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) on the one hand, and the Saturnian system and Titan on the other hand [1,2]. Titan, Saturn's largest satellite, is the only other object in our Solar system to possess an extensive nitrogen atmosphere, host to an active organic chemistry, based on the interaction of N2 with methane (CH4). Following the Voyager flyby in 1980, Titan has been intensely studied from the ground-based large telescopes (such as the Keck or the VLT) and by artificial satellites (such as the Infrared Space Observatory and the Hubble Space Telescope) for the past three decades. Prior to Cassini-Huygens, Titan's atmospheric composition was thus known to us from the Voyager missions and also through the explorations by the ISO. Our perception of Titan had thus greatly been enhanced accordingly, but many questions remained as to the nature of the haze surrounding the satellite and the composition of the surface. The recent revelations by the Cassini-Huygens mission have managed to surprise us with many discoveries [3-8] and have yet to reveal more of the interesting aspects of the satellite. The Cassini-Huygens mission to the Saturnian system has been an extraordinary success for the planetary community since the Saturn-Orbit-Insertion (SOI) in July 2004 and again the very successful probe descent and landing of Huygens on January 14, 2005. One of its main targets was Titan. Titan was revealed to be a complex world more like the Earth than any other: it has a dense mostly nitrogen atmosphere and active climate and meteorological cycles where the working fluid, methane, behaves under Titan conditions the way that water does on Earth. Its geology, from lakes and seas to broad river valleys and mountains, while carved in ice is, in its balance of processes, again most like Earth. Beneath this panoply of Earth-like processes an ice crust floats atop what appears to be a liquid water ocean. Titan is also rich in organic moleculesmore so in its surface and atmosphere than anyplace in the solar system, including Earth [4]. These molecules were formed in the atmosphere, deposited on the surface and, in coming into contact with liquid water may undergo an aqueous chemistry that could replicate aspects of life's origins. I will discuss our current understanding of Titan's complex environment in view of recent exploration, in particular on the atmospheric structure (temperature and composition), and the surface nature. I will show how these and other elements can give us clues as to the origin and evolution of the satellite, and how they connect to the observations of the planet and the other satellites and rings. Future space missions to Titan can help us understand the kronian and also our Solar System as a whole. In particular, I will describe the future exploration of Titan and the Saturnian System with TSSM, a mission studied jointly by ESA and NASA in 2008 [1] and prioritized second for a launch around 2023-2025. TSSM comprises a Titan Orbiter provided by NASA that would carry two Titan in situ elements provided by ESA: a montgolfiere and a lake-landing lander. The mission would arrive 9 years later for a 4-year duration in the Saturn system. Following delivery of the ESA in situ elements to Titan, the Titan Orbiter would explore the Saturn system via a 2-year tour that includes Enceladus and Titan flybys. The montgolfiere would last at least 6 months at Titan and the lake lander 8-10 hours. Following the Saturn system tour, the Titan Orbiter would culminate in a 2-year orbit around Titan. References 1. TSSM and EJSM NASA/ESA Joint Summary Report, 16 January 2009 2. Coustenis et al. (2008). TandEM: Titan and Enceladus mission. Experimenta( Astron-omy, 23, 893-946. 3. Coustenis, A.,

Coustenis, Athena

150

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, AURLIE--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 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

151

Do AES encryptions act randomly?  

Microsoft Academic Search

The Advanced Encryption Standard (AES) is widely recognized as the most\\u000aimportant block cipher in common use nowadays. This high assurance in AES is\\u000agiven by its resistance to ten years of extensive cryptanalysis, that has shown\\u000ano weakness, not even any deviation from the statistical behaviour expected\\u000afrom a random permutation. Only reduced versions of the ciphers have been

Anna Rimoldi; Massimiliano Sala; Enrico Bertolazzi

2010-01-01

152

Drill System Development for the Lunar Subsurface Exploration  

NASA Astrophysics Data System (ADS)

Reaching the cold traps at the lunar poles and directly sensing the subsurface regolith is a primary goal of lunar exploration, especially as a means of prospecting for future In Situ Resource Utilization efforts. As part of the development of a lunar drill capable of reaching a depth of two meters or more, Honeybee Robotics has built a laboratory drill system with a total linear stroke of 1 meter, capability to produce as much as 45 N-m of torque at a rotational speed of 200 rpm, and a capability of delivering maximum downforce of 1000 N. Since this is a test-bed, the motors were purposely chosen to be relative large to provide ample power to the drill system (the Apollo drill was a 500 Watt drill, i.e. not small in current standards). In addition, the drill is capable of using three different drilling modes: rotary, rotary percussive and percussive. The frequency of percussive impact can be varied if needed while rotational speed can be held constant. An integral part of this test bed is a vacuum chamber that is currently being constructed. The drill test-bed is used for analyzing various drilling modes and testing different drill bit and auger systems under low pressure conditions and in lunar regolith simulant. The results of the tests are used to develop final lunar drill design as well as efficient drilling protocols. The drill was also designed to accommodate a downhole neutron spectrometer for measuring the amount of hydrated material in the area surrounding the borehole, as well as downhole temperature sensors, accelerometers, and electrical properties tester. The presentation will include history of lunar drilling, challenges of drilling on the Moon, a description of the drill and chamber as well as preliminary drilling test results conducted in the ice-bound lunar regolith simulant with a variety of drill bits and augers systems.

Zacny, Kris; Davis, Kiel; Paulsen, Gale; Roberts, Dustyn; Wilson, Jack; Hernandez, Wilson

153

An Approach to Spectropolarimetry for Solar System Exploration  

NASA Astrophysics Data System (ADS)

An approach to spectropolarimetry is described which offers the prospect of high sensitivity over a very wide wavelength range (FUV, NUV, optical, NIR, MIR). Using static, robust components the polarization information is encoded onto one dimension of a two-dimensional data array, while the other dimension records the spectrum. No moving parts are required and all polarimetric information is available on a single data frame, hence the technique is immune to time dependencies, free of fragile modulating components, has the potential for high sensitivity while offering a wide wavelength range with full Stokes spectropolarimetry. In the Solar System, space-based spectropolarimetry offers diagnostics for dust (cometary, zodiacal, rings), surfaces (rocky, regolith, icy), aerosols (clouds, dust storms) and high energy plasma emission processes. Beyond the Solar System, space-based telescopic spectropolarimetry has important contributions to make in the detection of extrasolar planets and their characterization. There are astrobiological applications for full Stokes polarimetry stemming from the interaction of light with chiral living organisms, which offers the potential for a remote sensing detection capability for microbial life. The proposed instrumentation concept is exceptionally well-suited to future exploration missions given its light weight, small size and robustness, coupled to a versatile and powerful generic diagnostic method, spectropolarimetry.

Sparks, William B.

2013-10-01

154

Hardware-software co-design of AES on FPGA  

Microsoft Academic Search

This paper presents a compact hardware-software co-design of Advanced Encryption Standard (AES) on the field programmable gate arrays (FPGA) designed for low-cost embedded systems. The design uses MicroBlaze, a soft-core processor from Xilinx. The computationally intensive operations of the AES are implemented in hardware for better speed. The sub-byte calculation is designed with the help of the processor carrying out

Saambhavi Baskaran; Pachamuthu Rajalakshmi

2012-01-01

155

Design of an unmanned Martian polar exploration system  

NASA Astrophysics Data System (ADS)

The design of an unmanned Martian polar exploration system is presented. The system elements include subsystems for transportation of material from earth to Mars, study of the Martian north pole, power generation, and communications. Early next century, three Atlas 2AS launch vehicles will be used to insert three Earth-Mars transfer vehicles, or buses, into a low-energy transfer orbit. Capture at Mars will be accomplished by aerobraking into a circular orbit. Each bus contains four landers and a communications satellite. Six of the twelve total landers will be deployed at 60 deg intervals along 80 deg N, and the remaining six landers at 5 deg intervals along 30 deg E from 65 deg N to 90 deg N by a combination of retrorockets and parachutes. The three communications satellites will be deployed at altitudes of 500 km in circular polar orbits that are 120 deg out of phase. These placements maximize the polar coverage of the science and communications subsystems. Each lander contains scientific equipment, two microrovers, power supplies, communications equipment, and a science computer. The lander scientific equipment includes a microweather station, seismometer, thermal probe, x-ray spectrometer, camera, and sounding rockets. One rover, designed for short-range (less than 2 km) excursions from the lander, includes a mass spectrometer for mineral analysis, an auger/borescope system for depth profiling, a deployable thermal probe, and charge coupled device cameras for terrain visualization/navigation. The second rover, designed for longer-range (2-5 km) excursions from the lander, includes radar sounding/mapping equipment, a seismometer, and laser ranging devices. Power for all subsystems is supplied by a combination of solar cells, Ni-H batteries, and radioisotope thermoelectric generators. Communications are sequenced from rovers, sounding rockets, and remote sensors to the lander, then to the satellites, through the Deep Space Network to and from earth.

Baldwin, Curt; Chitwood, Denny; Demann, Brian; Ducheny, Jordan; Hampton, Richard; Kuhns, Jesse; Mercer, Amy; Newman, Shawn; Patrick, Chris; Polakowski, Tony

1994-07-01

156

Solar Mesosphere Explorer optical-mechanical systems engineering  

Microsoft Academic Search

Mission overview of the Solar Mesosphere Explorer is presented along with design analysis and summaries of results. The Solar Mesosphere Explorer is a spin stabilized satellite carrying a complement of four Ebert-Fastie spectrometers and a four-channel Mersenne radiometer. Description of the spectrometer is given including a telescope and its aberrations. The radiometer is also described with consideration given to isothermal

K. A. Gause; J. R. Stuart

1979-01-01

157

Explorations of Mariana Arc Volcanoes Reveal New Hydrothermal Systems  

NASA Astrophysics Data System (ADS)

Some 20,000 km of volcanic arcs, roughly one-third the length of the global mid-ocean ridge (MOR) system, rim the western Pacific Ocean. Compared to 25 years of hydrothermal investigations along MORs, exploration of similar activity on the estimated ~600 submarine arc volcanoes is only beginning [Ishibashi and Urabe, 1995; De Ronde et al., 2003]. To help alleviate this under-sampling, the R/V T. G. Thompson was used in early 2003 (9 February to 5 March) to conduct the first complete survey of hydrothermal activity along 1200 km of the Mariana intra-oceanic volcanic arc. This region includes both the Territory of Guam and the Commonwealth of the Northern Mariana Islands. The expedition mapped over 50 submarine volcanoes with stunning new clarity (Figures 1 and 2) and found active hydrothermal discharge at 12 sites, including the southern back-arc site. This includes eight new sites along the arc (West Rota, Northwest Rota, E. Diamante, Zealandia Bank, Maug Caldera, Ahyi, Daikoku, and Northwest Eifuku) and four sites of previously known hydrothermal activity (Seamount X, Esmeralda, Kasuga 2, and Nikko) (Figures 1 and 2). The mapping also fortuitously provided a ``before'' image of the submarine flanks of Anatahan Island, which had its first historical eruption on 10 May 2003 (Figures 1 and 3).

Embley, R. W.; Baker, E. T.; Chadwick, W. W., Jr.; Lupton, J. E.; Resing, J. A.; Massoth, G. J.; Nakamura, K.

2004-01-01

158

The invention that opened the solar system to exploration  

NASA Astrophysics Data System (ADS)

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 P 1 to a nearby planet P 2 such that its gravitational field (superimposed on the gravitational field of the Sun) catapults the vehicle to another planet P 3, which in turn is used to repeat the process. Thus, through a series of planetary encounters, a gravity-propelled trajectory P 1-P 2-P 3-P 4--P N is generated. This paper describes how the invention was conceived and how the difficult mathematical problem of computing the trajectories was solved in order to numerically investigate and use the invention in actual missions. The crucial roles played by the UCLA Computing Facility and the Departments of Mathematics and Physics are also described.

Minovitch, Michael A.

2010-05-01

159

New hole logging system tested for UK coal exploration  

SciTech Connect

Robertson Research Engineering Services was approached to look into the possibility of logging coal measure deposits for open pit coal exploration. Due to the development of a parallel-sided drill rod, it has now become possible to run geophysical logs through the rod. This, in fact, means that the need to pull the drill stem and to insert casing is avoided and much time, effort, and money may be saved. Thus, the rapid logging of coal boreholes using Robertson Research's gamma gamma density tool is now possible. Initial trials took place in Scotland to establish the principle that the equipment could log density and natural gamma satisfactorily through the drill rod. The short period of trials was successful and analysis of the results is being undertaken before starting a more vigorous program of development and trials to produce equipment to the specifications demanded by the National Coal Board, with particular reference to the operation of the equipment by the drilling company. In addition to gamma and density logging through the drill stem, gamma and laterologging have been carried out in open hole. The laterolog is particularly useful for the resolution of thin coal seams, which have a high electrical resistance. An additional and attractive advantage of the Wellog density logging system used in drill stem is that gamma radioactive sources are very small and are much less likely to be lost down the borehole.

Not Available

1980-09-01

160

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

161

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

Microsoft Academic Search

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.

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

1992-01-01

162

Spectroscopy of AE Circinus (Mennickent+, 2008)  

NASA Astrophysics Data System (ADS)

We present photometric time series obtained at La Silla and Cerro Tololo Inter American Observatory (CTIO) during several seasons. AE Cir was observed with the Dutch 0.9-m telescope at La Silla ESO observatory in the night of 2001 April 5/6 in the V band. We also observed AE Cir with the CTIO 1.3-m telescope operated under the Small and Moderate Aperture Research Telescope System (SMARTS) consortium in the seasons 2004 and 2005. Observations were made in pairs of two exposures in B and R each. We also present medium-resolution spectra of AE Cir obtained in 2000 May 29 and 30 with the 1.54-m Danish telescope at La Silla European Southern Observatory (ESO), high-resolution spectra obtained at the Paranal Observatory with the ESO-VLT-UT2 telescope during 2001 March 16, and a medium-resolution spectrum obtained at the CTIO with the 4-m Blanco telescope during 2007 May 04. (1 data file).

Mennickent, R.; Greiner, J.; Arenas, J.; Tovmassian, G.; Mason, E.; Tappert, C.; Papadaki, C.

2009-01-01

163

Talent in the taxi: a model system for exploring expertise  

PubMed Central

While there is widespread interest in and admiration of individuals with exceptional talents, surprisingly little is known about the cognitive and neural mechanisms underpinning talent, and indeed how talent relates to expertise. Because many talents are first identified and nurtured in childhood, it can be difficult to determine whether talent is innate, can be acquired through extensive practice or can only be acquired in the presence of the developing brain. We sought to address some of these issues by studying healthy adults who acquired expertise in adulthood. We focused on the domain of memory and used licensed London taxi drivers as a model system. Taxi drivers have to learn the layout of 25?000 streets in London and the locations of thousands of places of interest, and pass stringent examinations in order to obtain an operating licence. Using neuropsychological assessment and structural and functional magnetic resonance imaging, we addressed a range of key questions: in the context of a fully developed brain and an average IQ, can people acquire expertise to an exceptional level; what are the neural signatures, both structural and functional, associated with the use of expertise; does expertise change the brain compared with unskilled control participants; does it confer any cognitive advantages, and similarly, does it come at a cost to other functions? By studying retired taxi drivers, we also consider what happens to their brains and behaviour when experts stop using their skill. Finally, we discuss how the expertise of taxi drivers might relate to the issue of talent and innate abilities. We suggest that exploring talent and expertise in this manner could have implications for education, rehabilitation of patients with cognitive impairments, understanding individual differences and possibly conditions such as autism where exceptional abilities can be a feature.

Woollett, Katherine; Spiers, Hugo J.; Maguire, Eleanor A.

2009-01-01

164

HOMERE: a Multimodal System for Visually Impaired People to Explore Virtual Environments  

Microsoft Academic Search

This paper describes the HOMERE system: a multimodal system dedicated to visually impaired people to explore and navigate inside virtual environments. The system addresses three main applications: the preparation to the visit of an existing site, the training for the use of the blind cane, and the ludic exploration of virtual worlds.? The HOMERE system provides the user with different

Anatole Lcuyer; Pascal Mobuchon; Christine Mgard; Jrme Perret; Claude Andriot; Jean-pierre Colinot

2003-01-01

165

19 CFR 4.76 - Procedures and responsibilities of carriers filing outbound vessel manifest information via the AES.  

Code of Federal Regulations, 2013 CFR

...outbound vessel manifest information via the AES. 4.76 Section 4.76 Customs Duties...outbound vessel manifest information via the AES. (a) The sea carrier's module...component of the Automated Export System (AES) (see, part 192, subpart B,...

2013-04-01

166

Exploration Strategies for Model-based Learning in Multi-agent Systems: Exploration Strategies  

Microsoft Academic Search

An agent that interacts with other agents in multi-agent systems can benefit significantly from adapting to the others. When performing active learning, every agent's action affects the interaction process in two ways: The effect on the expected reward according to the current knowledge held by the agent, and the effect on the acquired knowledge, and hence, on future rewards expected

David Carmel; Shaul Markovitch

1999-01-01

167

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

Microsoft Academic Search

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

John C. Mankins

2002-01-01

168

Intelligent Systems Technologies for Human Space Exploration Mission Operations  

Microsoft Academic Search

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

Ernest E. Smith; David J. Korsmeyer

2011-01-01

169

FPGA implementation of AES encryption and decryption  

Microsoft Academic Search

Advanced Encryption Standard (AES), a Federal Information Processing Standard (FIPS), is an approved cryptographic algorithm that can be used to protect electronic data. The AES can be programmed in software or built with pure hardware. However Field Programmable Gate Arrays (FPGAs) offer a quicker and more customizable solution. This paper presents the AES algorithm with regard to FPGA and the

Ashwini M. Deshpande; Mangesh S. Deshpande; Devendra N. Kayatanavar

2009-01-01

170

Towards Efficient Design Space Exploration of Heterogeneous Embedded Media Systems  

Microsoft Academic Search

Modern signal processing and multimedia embedded systems increas- ingly have heterogeneous system architectures. In these systems, programmable processors provide flexibility to support multiple applications, while dedicated hardware blocks provide high performance for time-critical application tasks. The heterogeneity of these embedded systems and the varying demands of their grow- ing number of target applications greatly complicate the system design. As part

Andy D. Pimentel; Simon Polstra; Frank Terpstra; A. W. Van Halderen; Joseph E. Coffland; Louis O. Hertzberger

2002-01-01

171

Diagnostic expert systems: Encoding geological knowledge for an exploration play analysis  

Microsoft Academic Search

The U.S. Geological Survey is currently exploring the feasibility of applying diagnostic expert systems and knowledge-based acquisition techniques to the geologic analysis of sedimentary basins and petroleum exploration plays. This paper describes a unique approach to the design and application of a rule-based expert system to the analysis of exploration plays, a methodology commonly used to assess petroleum resources in

1993-01-01

172

Diversified Mixcolumn transformation of AES  

Microsoft Academic Search

In the Rijndael, one can replace some variations to produce different ciphers, including the irreducible polynomial, the affine transformation in the SubByte, the offsets in the ShiftRow, and the polynomial in the MixColumn, to increase the variety of the Advanced Encryption Standard (AES) algorithm. In this article we present three types of MixColumn polynomials that can be easily provided diversified

Ming-Haw Jing; Jian-Hong Chen; Zih-Heng Chen

2007-01-01

173

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  

SciTech Connect

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 mission s to Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. An initial technology baseline consisting of a NEBA 10 kWe, 1000 N thrust, 850 s, 1500 kg bimodal system was selected, and its performance examined against a data base for trajectories to outer solar system planetary destinations to select optimal direct and gravity assisted trajectories for study. A conceptual design for a common bimodal spacecraft capable of performing missions to all the planetary destinations was developed and made the basis of end to end mission designs for orbiter missions to Jupiter, Saturn, and Neptune. Concepts for microspacecraft capable of probing Jupiter`s atmosphere and exploring Titan were also developed. All mission designs considered use the Atlas 2AS for launch. It is shown that the bimodal nuclear power and propulsion system offers many attractive option for planetary missions, including both conventional planetary missions in which all instruments are carried by a single primary orbiting spacecraft, and unconventional missions in which the primary spacecraft acts as a carrier, relay, and mother ship for a fleet of micro spacecraft deployed at the planetary destination.

NONE

1995-12-08

174

Revolutionary Design for Astronaut Exploration - Beyond the Bio-Suit System  

Microsoft Academic Search

The Bio-Suit System is designed to revolutionize human space exploration by providing enhanced astronaut extravehicular activity (EVA) locomotion and performance based on the concepts of a `second skin' capability. The novel Bio-Suit concept provides an overall exploration system realized through symbiotic relationships between a suite of advanced technologies, creative design, human modeling and analysis, and new mission operations techniques. By

Dava J. Newman; Marita Canina; Guillermo L. Trotti

2007-01-01

175

Revolutionary Design for Astronaut Exploration Beyond the Bio-Suit System  

Microsoft Academic Search

The Bio-Suit System is designed to revolutionize human space exploration by providing enhanced astronaut extravehicular activity (EVA) locomotion and performance based on the concepts of a second skin capability. The novel Bio-Suit concept provides an overall exploration system realized through symbiotic relationships between a suite of advanced technologies, creative design, human modeling and analysis, and new mission operations techniques. By

Dava J. Newman; Marita Canina; Guillermo L. Trotti

2007-01-01

176

A systems study to determine the attractiveness of solar system sites for eventual human exploration  

Microsoft Academic Search

A pre-phase A idea-generation team at the-Jet Propulsion Laboratory (JPL) has conducted a study to rank notable locations in the solar system based on attractiveness for human exploration. The process used to perform the study was composed of the following primary steps: determination of ranking criteria (including value, cost, and risk criteria) upon which to rate sites in the solar

J. M. Andringa; A. A. Gray

2005-01-01

177

Metrics for design space exploration of heterogeneous multiprocessor embedded systems  

Microsoft Academic Search

This paper considers the problem of designing heterogeneous multiprocessor embedded systems. The focus is on a step of the design flow: the definition of innovative metrics for the analysis of the system specification to statically identify the most suitable processing elements class for each system functionality. Experimental results are also included, to show the applicability and effectiveness of the proposed

Donatella Sciuto; Fabio Salice; Luigi Pomante; William Fornaciari

2002-01-01

178

Scaling System-Level Science: Scientific Exploration and IT Implications  

Microsoft Academic Search

The study and creation of the infrastructure required to enable system-level science--the integration of diverse sources of knowledge about the constituent parts of a complex system with the goal of obtaining an understanding of the system's properties as a whole--is becoming increasingly important, spawning new knowledge in variety of fields at a rapid pace.

Ian T. Foster; Carl Kesselman

2006-01-01

179

A forced inflated parachute system to explore earth environment  

Microsoft Academic Search

A new parachute system is being developed in order to study the lower thermosphere and mesosphere of the earth, the region left fairly unexplored so far because conventional in-situ measurement technique can not be properly applied in these regions. After the system is ejected from a rocket at the height of 120-130 km, the parachute of the system is forced

Koh-Ichiro Oyama; Motoki Hinada; Yasuo Hashimoto; Yoshiyuki Tokunaga; Michiyoshi Namiki; Shinji Saito; Atsushi Nakata; Masanori Takasaki; Nobuki Kawashima

1992-01-01

180

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

181

Exploration System Mission Directorate and Constellation Program Support for Analogue Missions.  

National Technical Information Service (NTIS)

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 pub...

C. E. Gerty S. A. Voels S. J. Hoffman

2008-01-01

182

A forced inflated parachute system to explore earth environment  

NASA Astrophysics Data System (ADS)

A new parachute system is being developed in order to study the lower thermosphere and mesosphere of the earth, the region left fairly unexplored so far because conventional in-situ measurement technique can not be properly applied in these regions. After the system is ejected from a rocket at the height of 120-130 km, the parachute of the system is forced to inflate. It, however still gains the falling velocity down to 85 km and only below this level the velocity is gradually reduced. In order to reduce the falling velocity to values less than 500 m/sec., the total weight of the system should be less than 5 kg. This includes telemetry system, battery and scientific instruments plus the parachute . Part of the system is conductive so that the system can be tracked from the ground by a radar in order to obtain wind information which is closely related to the geophysical parameters to be measured.

Oyama, Koh-Ichiro; Hinada, Motoki; Hashimoto, Yasuo; Tokunaga, Yoshiyuki; Namiki, Michiyoshi; Saito, Shinji; Nakata, Atsushi; Takasaki, Masanori; Kawashima, Nobuki

183

Exploring the Role of Management Accounting Systems in Strategic Sensemaking  

Microsoft Academic Search

Management accounting systems (MAS) provide an information context that is required for strategic sensemaking. Research from the interpretive perspective of information processing suggests some mechanisms how MAS can contribute to strategic sensemaking, although it neglects the relationship between MAS use and MAS dimensions. The systems-structural perspective identified some important MAS dimensions, but it does not explain how these dimensions contribute

Marcus Heidmann; Utz Schffer; Susanne Strahringer

2008-01-01

184

PHYSICS AND CONTROL: EXPLORING PHYSICAL SYSTEMS BY FEEDBACK  

Microsoft Academic Search

The subject and methodology of an emerging field of cybernetical physics related both to physics and to control are outlined. The aim of a cyberphysical investigation is studying a physical system by means of controlling it. The conservation laws give up their place to the transformation laws. Examples of transformation laws describing the excitability properties of dissipative systems are presented

A. L. Fradkov

185

Hierarchical design space exploration for a class of digital systems  

Microsoft Academic Search

This paper presents an architectural synthesis approach for a widely used class of digital systems characterized by inherent regularity in their description. This approach relies on a novel modeling or abstraction of the problem domain to facilitate a hierarchical solution method. The modeling is based on exploiting the inherent regularity in the system description to cluster its behavioral operations. The

D. Sreenivasa Rao; Fadi J. Kurdahi

1993-01-01

186

Spacewalker: Automated Design Space Exploration for Embedded Computer Systems  

Microsoft Academic Search

This paper addresses the problem of automated design of a computer system for an embedded application. The computer system to be designed consists of a VLIW processor and\\/or a customized systolic array, along with a cache subsystem comprising a data cache, instruction cache and second-level unified cache. Several algorithms for \\

Greg Snider

2001-01-01

187

The synergy of biology, intelligent systems, and space exploration  

Microsoft Academic Search

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

E. Mjolsness; A. Tavormina

2000-01-01

188

Exploring design space for an integrated intelligent system  

Microsoft Academic Search

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

Nick Hawes; Jeremy Wyatt; Aaron Sloman

2009-01-01

189

MarsVac: Pneumatic Sampling System for Planetary Exploration  

Microsoft Academic Search

We are proposing a Mars Sample Return scheme whereby a sample of regolith is acquired directly into a Mars Ascent Vehicle using a pneumatic system. Unlike prior developments that used suction to collect fines, the proposed system uses positive pressure to move the regolith. We envisage 3 pneumatic tubes to be embedded inside the 3 legs of the lander. Upon

K. Zacny; G. Mungas; P. Chu; J. Craft; K. Davis

2008-01-01

190

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

191

Supporting exploration and collaboration in scientific workflow systems  

Microsoft Academic Search

As the amount of observation data captured everyday increases, running scientific workflows will soon become a fundamental step of scientific inquiry. Current scientific workflow systems offer ways to link together data, software and computational resources, but often accomplish this by requiring a deep understanding of the system with a steep learning curve. Thus, there is a need to lower user

L. Marini; R. Kooper; P. Bajcsy; J. Myers

2007-01-01

192

Collecting in Central Asia: National Plant Germplasm System Plant Explorations  

Technology Transfer Automated Retrieval System (TEKTRAN)

The USDA-ARS National Plant Germplasm System is charged with the preservation of economically important crop plants and their wild relatives. Curators in the System strive to develop collections capturing the genetic diversity of each species. One mechanism for filling gaps in collections is through...

193

The roles of humans and robots in exploring the solar system.  

PubMed

Historically, advocates of solar system exploration have disagreed over whether program goals could be entirely satisfied by robotic missions. Scientists tend to argue that robotic exploration is most cost-effective. However, the human space program has a great deal of support in the general public, thereby enabling the scientific element of exploration to be larger than it might be as a stand-alone activity. A comprehensive strategy of exploration needs a strong robotic component complementing and supporting human missions. Robots are needed for precursor missions, for crew support on planetary surfaces, and for probing dangerous environments. Robotic field assistants can provide mobility, access to scientific sites, data acquisition, visualization of the environment, precision operations, sample acquisition and analysis, and expertise to human explorers. As long as space exploration depends on public funds, space exploration must include an appropriate mix of human and robotic activity. PMID:15791731

Mendell, W W

2004-07-01

194

Exploring Complex Systems Aspects of Blackout Risk and Mitigation  

SciTech Connect

Electric power transmission systems are a key infrastructure, and blackouts of these systems have major consequences for the economy and national security. Analyses of blackout data suggest that blackout size distributions have a power law form over much of their range. This result is an indication that blackouts behave as a complex dynamical system. We use a simulation of an upgrading power transmission system to investigate how these complex system dynamics impact the assessment and mitigation of blackout risk. The mitigation of failures in complex systems needs to be approached with care. The mitigation efforts can move the system to a new dynamic equilibrium while remaining near criticality and preserving the power law region. Thus, while the absolute frequency of blackouts of all sizes may be reduced, the underlying forces can still cause the relative frequency of large blackouts to small blackouts to remain the same. Moreover, in some cases, efforts to mitigate small blackouts can even increase the frequency of large blackouts. This result occurs because the large and small blackouts are not mutually independent, but are strongly coupled by the complex dynamics.

Newman, David E [University of Alaska; Carreras, Benjamin A [ORNL; Lynch, Vickie E [ORNL; Dobson, Ian [University of Wisconsin, Madison

2011-01-01

195

Fireball models for flares in AE Aquarii  

NASA Astrophysics Data System (ADS)

We examine the flaring behaviour of the cataclysmic variable AE Aqr in the context of the `magnetic propeller' model for this system. The flares are thought to arise from collisions between high-density regions in the material expelled from the system after interaction with the rapidly rotating magnetosphere of the white dwarf. We calculate the first quantitative models for the flaring and calculate the time-dependent emergent optical spectra from the resulting hot, expanding ball of gas. We compare the results under different assumptions to observations and derive values for the mass, length-scale and temperature of the material involved in the flare. We see that the fits suggest that the secondary star in this system has Population II composition.

Pearson, K. J.; Horne, Keith; Skidmore, Warren

2003-02-01

196

Specify-explore-refine paradigm for system design  

NASA Astrophysics Data System (ADS)

Design effort is focusing on increasingly higher levels of abstraction, as methodologies and tools for chip-level design matrix. We present a methodology and tool for system-level specification, design and refinement, that yield a set of system components, where each is described with a functional specification. The specification for each component can then be synthesized into hardware or compiled to software. We highlight advantages of the proposed methodology compared to current practice.

Vahid, Frank; Narayan, Sanjiv; Gong, Jie; Gajski, Daniel

1996-03-01

197

Exploring Design Space For An Integrated Intelligent System  

Microsoft Academic Search

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

Nick Hawes; Jeremy Wyatt; Aaron Sloman

2009-01-01

198

Multiwavelength observing campaign on AE Aqr  

NASA Astrophysics Data System (ADS)

Dr. Christopher Mauche, Lawrence Livermore National Laboratory, and colleagues in Spain and Oman have requested AAVSO observations in support of their upcoming multiwavelength observations of the novalike intermediate polar cataclysmic variable AE Aqr with the Swift satellite, the MAGIC (Major Atmospheric Gamma Imaging Cherenkov) telescope on La Palma, Canary Islands, and telescopes at other ground-based observatories in Serbia, Crete, and La Palma. Their goal is to study the extreme high-energy (gamma-ray) and high-energy (x-ray) behavior of this complex system. AAVSO observations will be critical to the success of this campaign. Dates of the MAGIC observations in May and June are given. B-band photometry is requested during and 1 hour around the times of the MAGIC observations in order to correlate the multiwavelength observations of this campaign. To help establish the context for the B observations during the MAGIC observations, please begin making nightly B observations of AE Aqr now, and continue through the end of June 2012. Visual observations and photometry in other bands are also welcome. Observations should be reported to the AAVSO International Database.

Waagen, Elizabeth O.

2012-05-01

199

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.

200

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

201

A drill-soil system modelization for future Mars exploration  

Microsoft Academic Search

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

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

2004-01-01

202

Exploration of Career Information Delivery Systems Via Computerization.  

ERIC Educational Resources Information Center

|Based on research conducted by Southwest Virginia Community College, this monograph presents information in a variety of formats on seven computerized career information systems: (1) microcomputers, which have the advantage of low cost, amenability to the production of locally generated databases, and portability; (2) the Coordinated Occupational

Moore, Rod; And Others

203

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

National Technical Information Service (NTIS)

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 se...

R. A. Stephan

2011-01-01

204

Exploration of the Jovian System Tapping Jupiter's Rotational Energy  

Microsoft Academic Search

Tours of the great outer planets and their moons can be accomplished by utilizing an electrodynamic tether attached to the spacecraft as both power system and propulsion device. Through interaction with the planetary magnetic field and inner plasmasphere, the tether could get electrical power, and either thrust or drag, out of the rotational motion of the planet; the relatively low

J. R. Sanmartin; E. C. Lorenzini

2004-01-01

205

HADES-high-level architecture development and exploration system  

Microsoft Academic Search

The authors propose a new approach to high level behavioural synthesis starting from an algorithmic description in Hardware C. The algorithm is compiled into a corresponding data\\/control flow graph including several optimizations. The behavioural synthesis part of the system performs transformations like loop unrolling, parallelization, etc., whereby the user is supported through a feedback loop. For final structural synthesis an

P. Poechmueller; M. Held; N. Wehn; M. Glesner

1991-01-01

206

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 33 cm2 pinhole, while lower divergence requirements of 0.5 can do with a smaller pinhole of 22 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

207

Exploring the Solar System? Let the Math Teachers Help!  

ERIC Educational Resources Information Center

|Scale measurement and ratio and proportion are topics that fall clearly in the middle-grades mathematics curriculum in Texas. So does the solar system. In their experience, the authors have found that students have trouble manipulating, much less comprehending, very large numbers and very small numbers. These concepts can be brought into

Charles, Karen; Canales, J. D.; Smith, Angela; Zimmerman, Natalie

2012-01-01

208

Exploring the Solar System with a Human Orrery  

ERIC Educational Resources Information Center

|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 paper or across a school grounds or campus. Other activities that investigate the motion of the planets are often

Newbury, Peter

2010-01-01

209

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

Microsoft Academic Search

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

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

1999-01-01

210

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

211

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

Microsoft Academic Search

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

Norbert Frischauf

2004-01-01

212

Concepts for future exploration for submarine fan and turbidite system reservoirs  

Microsoft Academic Search

With the emphasis of future petroleum exploration in deeper water and on frontier plays, submarine fan and turbidite systems will be major reservoir targets. Successful exploration and development of these reservoirs will be largely controlled by world oil prices, politics, markets, and drilling and producing technologies. Present economics require large reserves when targeting deep water or when drilling remote regions

M. H. Link; P. Weimer

1990-01-01

213

A New Counselee Assessment-Occupational Exploration System and Its Interest and Aptitude Dimensions.  

ERIC Educational Resources Information Center

Describes construction of an occupational classification structure and development of interest and aptitude measures for assessing counselees in relation to these two primary dimensions of the structure. Details uses of the Guide for Occupational Exploration, the keystone of the new counselee assessment-occupational exploration system. (RC)

Droege, Robert C.; Padgett, Adaline

1982-01-01

214

SP100 space reactor power system for lunar, Mars, and robotic exploration  

Microsoft Academic Search

The SP-100 power system is described which was developed for three missions, namely, Pluto Orbiter with nuclear electric propulsion; human-rated surface reactor power system for lunar and Mars exploration; and earth surveillance with an integrated nuclear electric propulsion system. The reactor power systems technology is being developed to meet these requirements so that the technical database, design tools, and specifications

Jack F. Mondt

1992-01-01

215

Exploring the Fitness Relationship between System Functionality and Business Needs  

Microsoft Academic Search

Fitting information systems to business needs is considered equally important by both, the Requirements Engineering and MIS\\u000a communities. Even though alignment\\/fit clearly appears as desirable, a number of issues still remain unsolved as for example:\\u000a (i) the achievement of alignment (ii) its management over time, (iii) the identification of non fit and, (iv) its evaluation.\\u000a This paper gives to fitness

Colette Rolland

2009-01-01

216

Visualization and exploration for recommender systems in enterprise organization  

NASA Astrophysics Data System (ADS)

Recommender systems seek to predict the interest a user would find in an item, person or social element they had not yet considered, based upon the properties of the item, the user's past experience and similar users. However, recommended items are often presented to the user with no context and no ability to influence the results. We present a novel visualization technique for recommender systems in which, a user can see the items recommended for him, and understand why they were recommended. Focusing on a user, we render a planar visualization listing a set of recommended items. The items are organized such that similar items reside nearby on the screen, centered around realtime generated categories. We use a combination of iconography, text and tag clouds, with maximal use of screen real estate, and keep items from overlapping to produce our results. We apply our visualization to expert relevance maps in the enterprise and a book recommendation system for consumers. The latter is based on Shelfari, a social network for reading and books.

Karni, Z.; Shapira, L.

2013-03-01

217

PLAN-IT - Scheduling assistant for solar system exploration  

SciTech Connect

A frame-based expert scheduling system shell, PLAN-IT, is developed for spacecraft scheduling in the Request Integration Phase, using the Comet Rendezvous Asteroid Flyby (CRAF) mission as a development base. Basic, structured, and expert scheduling techniques are reviewed. Data elements such as activity representation and resource conflict representation are discussed. Resource constraints include minimum and maximum separation times between activities, percentage of time pointed at specific targets, and separation time between targeted intervals of a given activity. The different scheduling technique categories and the rationale for their selection are also considered. 13 references.

Dias, W. C.; Henricks, J. A.; Wong, J. C.

1987-01-01

218

MarsVac: Pneumatic Sampling System for Planetary Exploration  

NASA Astrophysics Data System (ADS)

We are proposing a Mars Sample Return scheme whereby a sample of regolith is acquired directly into a Mars Ascent Vehicle using a pneumatic system. Unlike prior developments that used suction to collect fines, the proposed system uses positive pressure to move the regolith. We envisage 3 pneumatic tubes to be embedded inside the 3 legs of the lander. Upon landing, the legs will burry themselves into the regolith and the tubes will fill up with regolith. With one puff of gas, the regolith can be lifted into a sampling chamber onboard of the Mars Ascent Vehicle. An additional chamber can be opened to acquire atmospheric gas and dust. The entire MSR will require 1) an actuator to open/close sampling chamber and 2) a valve to open gas cylinder. In the most recent study related to lunar excavation and funded under the NASA SBIR program we have shown that it is possible lift over 3000 grams of soil with only 1 gram of gas at 1atm. Tests conducted under Mars atmospheric pressure conditions (5 torr). In September of 2008, we will be performing tests at 1/6thg (Moon) and 1/3g (Mars) to determine mass lifting efficiencies in reduced gravities.

Zacny, K.; Mungas, G.; Chu, P.; Craft, J.; Davis, K.

2008-12-01

219

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

220

Retrievable exploration guide base/completion guide base system  

SciTech Connect

A system is described for converting a subsea exploratory well into a production well. The well includes a temporary guide base located subsea with guide lines extending to the water surface and a central opening through which drilling operations are conducted. A method of converting a subsea exploratory well into a production well is described comprising the steps of: locating a temporary guide base on a subsea mud line, providing a permanent guide base in two parts latched together, providing a wellhead housing with an external latching profile and assembling the two parts of the permanent guide base and the wellhead housing together and lowering the assembly onto the temporary guide base, releasing part of the permanent guide base leaving the second part of the permanent guide base and the wellhead housing subsea, providing a completion guide base with equipment for producing from the well and lowering the completion guide base on to the temporary guide base.

Hed, J.E.; Draper, R.B.

1986-09-16

221

Application of a SNTP-Based Propulsion/Power System to Solar System Exploration Missions  

NASA Astrophysics Data System (ADS)

A ``bi-modal'' nuclear propulsion and power system based on the United States Air Force's (USAF's)* Space Nuclear Thermal Propulsion (SNTP) technology is applied to a set of high energy Solar system exploration missions. Performance comparisons are made to a baseline mission set developed by the Jet Propulsion Laboratory utilizing a nuclear electric propulsion system based on the SP-100 space power system. Orbiters and probes of Uranus, Neptune, and Pluto, a Grand Tour of the Galilean moons of Jupiter, a Comet Nucleus Sample Return, and a Multiple Mainbelt Asteroid Rendezvous mission are analyzed. The first five missions utilizing SP- 100 required a Shuttle-C or equivalent heavy lift launcher. With the bi-modal PBR system, the payload goals are deliverable in the same transit times, but on the smaller, existing Titan IV launcher. Furthermore, all optional payloads originally available only at increased transit time are accommodated. Available mass margins for these missions are 20%-85% of the power/propulsion system mass, providing significant robustness. The same missions were analyzed on a Titan III launcher in order to pursue further cost reductions. Substantial payload masses (1000 kg or more) were found to be available in all cases with reasonable transit times, coinciding well with the current ``lighter, faster, cheaper'' NASA philosophy.

Venetoklis, Peter S.; Nelson, Caroline V.; Gustafson, Eric R.

1994-07-01

222

Mission to the Solar System: Exploration and Discovery. A Mission and Technology Roadmap.  

National Technical Information Service (NTIS)

Solar System exploration addresses some of humanity's most fundamental questions: How and when did life form on Earth. Does life exist elsewhere in the Solar System or in the Universe. - How did the Solar System form and evolve in time. - What can the oth...

1998-01-01

223

Co-simulation platform based on systemc for multiprocessor system on chip architecture exploration  

Microsoft Academic Search

Currently multiprocessor embedded systems are the principal vectors of semiconductor industry. Modelling, validating and analyzing a system performances impose the evolution of the traditional simulation techniques. In this paper we define the methodology we used in constructing the STARSoC co-simulation environment. This platform aims to explore at higher levels of abstractions a multiprocessors system on chip architectures. The platform reference

Sami BOUKHECHEM; El-Bay BOURENNANE; Halim SAMAHI

2007-01-01

224

The petroleum system as an exploration tool in a frontier setting  

Microsoft Academic Search

Use of the petroleum system concept as an exploration tool requires synthesis of the influence of three geological processes connected in space and time to create each petroleum system. These three processes are the generation, migration, and trapping of petroleum. An evaluation procedure that makes this synthesis provides a logical mechanism for ranking the conceptual petroleum systems in a given

1991-01-01

225

Nuclear Electric Propulsion: A Better, Safer, Cheaper Transportation System for Human Exploration of Mars  

Microsoft Academic Search

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

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

1994-01-01

226

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

Microsoft Academic Search

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

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

1994-01-01

227

Nuclear Electric Propulsion: A ``Better, Safer, Cheaper'' Transportation System for Human Exploration of Mars  

Microsoft Academic Search

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

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

1994-01-01

228

Multiwavelength Observations of the Flares and Oscillations AE AQR  

NASA Astrophysics Data System (ADS)

The cataclysmic variable AE Aquarii is unique among the objects of its class because of its large-amplitude, aperiodic flaring activity, which presents a puzzle to our understanding of the underlying powerhouse. It also harbors the most rapidly spinning white dwarf known (spin period: 33s). Although AE Aqr has been the subject of systematic scrutiny at many different bands, and with a variety of observatories and instruments (including the HST), many puzzling aspects of its behavior are still not understood. In appreciation of the potential importance of AE Aqr as a laboratory for studying the physics of accretion, the Astronomical community has decided to undertake a large, coordinated campaign for monitoring this system across the electromagnetic spectrum. We propose to participate in this undertaking by using the HST to obtain near-UV spectra of AE Aqr with high time resolution simultaneously wiht other space-based and Earth-based observatories, in particular with the ROSAT observatory which is scheduled to observe the system in the soft X-ray band. This project plays up to the particular strengths of the HST, namely its high sensitivity and spectral resolution in the near-UV band, which is not accessible by Earth-based telescopes, and its ability to carry out spectroscopy with extremely high time resolution.

Horne, Keith

1993-07-01

229

Efficient AES implementations for ARM based platforms  

Microsoft Academic Search

The Advanced Encryption Standard (AES) contest, started by the U.S. National Institute of Standards and Technology (NIST), saw the Rijndael [13] algorithm as its winner [11]. Although the AES is fully defined in terms of functionality, it requires best exploitation of architectural parameters in order to reach the optimum performance on specific architectures. Our work concentrates on ARM cores [1

Kubilay Atasu; Luca Breveglieri; Marco Macchetti

2004-01-01

230

Multiplicative Masking and Power Analysis of AES  

Microsoft Academic Search

Abstract: The recently proposed multiplicative masking countermeasureagainst power analysis attacks on AES is interesting as it does notrequire the costly recomputation and RAM storage of S-boxes for everyrun of AES. This is important for applications where the available spaceis very limited such as the smart card applications. Unfortunately, it ishere shown that this method is in fact inherently vulnerable to

Jovan Dj. Golic; Christophe Tymen

2002-01-01

231

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

232

A magnetic propeller in the cataclysmic variable AE Aquarii  

NASA Astrophysics Data System (ADS)

Current treatments of accretion flows in magnetic cataclysmic variables (CVs) imply that the criterion for disc formation depends only on the accretion rate and the magnetic field strength, and is independent of the spin rate of the accreting star. The low accretion rate in the moderately magnetic CV AE Aqr should allow disc formation, yet the single-peaked Balmer emission lines show no evidence of a disc. We interpret these data as evidence that the rapidly rotating white dwarf in AE Aqr ejects most of the matter transferred from the secondary. The possibility of such states was pointed out in earlier theoretical work modelling the gas flow as inhomogeneous and diamagnetic. Explicit application of this model to AE Aqr accounts for the observed spin-down of the white dwarf, and gives estimates of the white dwarf magnetic moment and the mass transfer rate as ~10^32 G cm^3 and >~10^17 g s^-1 respectively. We show that AE Aqr is likely to alternate between phases of disc accretion, in which the white dwarf spins up, and propeller states (as observed) in which it spins down. We comment on the likely consequences for other magnetic systems.

Wynn, Graham A.; King, Andrew R.; Horne, Keith

1997-04-01

233

Rare-earth metals (REMs) in nickel aluminide-based alloys: I. Physicochemical laws of interaction in the Ni-Al-REM and Ni x Al y -REM-AE (alloying element) systems  

NASA Astrophysics Data System (ADS)

The data on the Ni-Al- R ( R = REM Sc, Y, La, lanthanides) binary and ternary systems and the interactions of three rare-earth metals (yttrium, lanthanum, cerium) with the main alloying elements (Ti (Zr, Hf), Cr (Mo, W) that are introduced into Ni3Al-based VKNA alloys are analyzed. The binary aluminides of REMs in the Ni-Al- R ternary systems are shown to be in equilibrium with neither NiAl nor Ni3Al. The solid solution of aluminum in RNi5, which penetrates deep into these ternary systems, is the most stable phase in equilibrium with Ni3Al. In the NiAl (Ni3Al)-AE- R systems, REM precipitation (segregation) on various defects and interfaces in nickel aluminides is likely to be the most probable, and REMs are thought to interact with the most active impurities in real alloys (C, O, N), since REMs have a large atomic radius and, thus, are virtually undissolved in nickel, aluminum, and nickel aluminides.

Povarova, K. B.; Kazanskaya, N. K.; Drozdov, A. A.; Morozov, A. E.

2008-02-01

234

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

NASA Astrophysics Data System (ADS)

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

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

1991-12-01

235

HUMAN-CENTRIC INTELLIGENT SYSTEMS FOR DESIGN EXPLORATION AND KNOWLEDGE DISCOVERY  

Microsoft Academic Search

This invited paper discusses research and development relating to computational intelligence (CI) technologies comprising powerful machine-based search and exploration systems that can generate, extract, process and visualise high-quality information from complex, poorly understood design domains. The integration and capture of user experiential knowledge within such systems in order to stimulate, support and increase understanding is of particular interest. The manner

I. C. Parmee

236

The systems developer skill set: exploring nature, gaps, and gender differences research in progress  

Microsoft Academic Search

IT workers need an appropriate skill set to effectively exploit technology. The purpose of this study is to explore the nature of actual and desired systems developer, job skills. In viewing job skills from a social constructivist viewpoint, this study also investigates the perspectives of male and female systems developers recognizing that societal influences related to gender may affect IT

Sandra K. Newton; Cynthia LeRouge; J. Ellis Blanton

2003-01-01

237

Immune system changes during simulated planetary exploration on Devon Island, high arctic  

Microsoft Academic Search

BACKGROUND: Dysregulation of the immune system has been shown to occur during spaceflight, although the detailed nature of the phenomenon and the clinical risks for exploration class missions have yet to be established. Also, the growing clinical significance of immune system evaluation combined with epidemic infectious disease rates in third world countries provides a strong rationale for the development of

Brian Crucian; Pascal Lee; Raymond Stowe; Jeff Jones; Rainer Effenhauser; Raymond Widen; Clarence Sams

2007-01-01

238

Operationalizing sustainability: exploring options for environmentally friendly flower bulb production systems  

Microsoft Academic Search

Current production systems for flower bulbs in the Netherlands employ considerable quantities of pesticides and nutrients per unit area. In 1993, an association of growers and environmentalists set out to design new farming systems that meet environmental objectives in addition to economic objectives. To support the design process, an explorative study was carried out to bring together the fragmented agronomic

Walter A. H. Rossing; Jan Eelco Jansma; Frank J. De Ruijter; Jan Schans

1997-01-01

239

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

240

Allosteric Transitions of Supramolecular Systems Explored by Network Models: Application to Chaperonin GroEL  

Microsoft Academic Search

Identification of pathways involved in the structural transitions of biomolecular systems is often complicated by the transient nature of the conformations visited across energy barriers and the multiplicity of paths accessible in the multidimensional energy landscape. This task becomes even more challenging in exploring molecular systems on the order of megadaltons. Coarse-grained models that lend themselves to analytical solutions appear

Zheng Yang; Peter Mjek; Ivet Bahar

2009-01-01

241

Rock Mechanics and Enhanced Geothermal Systems: A DOE-sponsored Workshop to Explore Research Needs  

Microsoft Academic Search

This workshop on rock mechanics and enhanced geothermal systems (EGS) was held in Cambridge, Mass., on June 20-21 2003, before the Soil and Rock America 2003 International Conference at MIT. Its purpose was to bring together experts in the field of rock mechanics and geothermal systems to encourage innovative thinking, explore new ideas, and identify research needs in the areas

Francois Heuze; Peter Smeallie; Derek Elsworth; Joel L. Renner

2003-01-01

242

Supporting and Frustrating Organizational Learning: Exploring the Role of Information Systems in Processes of Organizational Learning  

Microsoft Academic Search

In this paper we aim to gain insight in the effects information systems have on organizational learning. A theoretical framework is proposed that may serve to explore the role of information systems in processes of organizational learning. Based on the sociology of knowledge, learning is conceived as the process of constructing and reconstructing organizational knowledge, which can be further broken

Marleen Huysman; Heico Van Der Blonk

1998-01-01

243

Method for exploring and discovering uranium deposits within a petrofluid system. [Patent Application  

Microsoft Academic Search

This invention relates to a method for exploring and discovering a uranium ore deposit located within a petrofluid system, comprising assaying the fluids and solids at a multiplicity of sites throughout the system with respect to at least four uranium daughter products, polonium-210, lead-210, bismuth-214, and radon-222 and thereby determining distances from the ore deposit to the assay point.

R. V. Gentry; I. L. Thomas; R. L. Hann

1978-01-01

244

Research and Exploration on the Improvement of Local System-Transformation Colleges in Core Competence  

Microsoft Academic Search

The core competence of the college is the key factor for the college to secure competitive advantages in severe competition. After transferring to the system of local management, local some local system-transformation colleges have found a way to develop quickly through more than 10 years of practice and exploration. By reference to the practice of university where the author serves,

Zheng Xu; Li Ping; Xia Mingyuan

2010-01-01

245

Petroleum geology reference system (PGREF) - a computerized bibliographic reference system for research and exploration applications  

SciTech Connect

The Petroleum Geology Reference System (PGREF) is a relational data base that contains more than 3300 citations representing reports, abstracts, and maps published between 1972 and the present by the Branch of Petroleum Geology, US Geological Survey (USGS). (Use of trade names is for descriptive purposes only and does not imply endorsement by the USGS.) PGREF is very specialized, easy to use, and useful for a wide variety of petroleum research and exploration applications. The data base represents the scope of research in the branch, including studies about source rocks, reservoir rocks, enhanced oil recovery, and unconventional oil and gas resources; organic geochemistry; stratigraphy; petrology; seismic interpretation of US basins; and resource assessment. System benefits include (1) publication or report-ready references; (2) online tracking of manuscripts during the approval and editing process; (3) ability to search for citations by subject and geographic location of subject; and (4) compilation and maintenance of references by year(s), author(s), and subject(s).

Obuch, R.C.; Takahashi, K.I.; Dyman, T.S.; Gautier, D.L.; Colburn, H.Y.

1989-03-01

246

Characterization of radioactive contamination inside pipes with the Pipe Explorer{trademark} system. Final report  

SciTech Connect

The Department of Energy (DOE) is currently in the process of decommissioning and dismantling many of its nuclear materials processing facilities that have been in use for several decades. Site managers throughout the DOE complex must employ the safest and most cost effective means to characterize, remediate and recycle or dispose of hundreds of miles of potentially contaminated piping and duct work. The DOE discovered that standard characterization methods were inadequate for its pipes, drains, and ducts because many of the systems are buried or encased. In response to the DOE`s need for a more specialized characterization technique, Science and Engineering Associates, Inc. (SEA) developed the Pipe Explorer{trademark} system through a DOE Office of Science and Technology (OST) contract administered through the Federal Energy Technology Center (FETC). The purpose of this report is to serve as a comprehensive overview of all phases of the Pipe Explorer{trademark} development project. The report is divided into 6 sections. Section 2 of the report provides an overview of the Pipe Explorer{trademark} system, including the operating principles of using an inverting membrane to tow sensors into pipes. The basic components of the characterization system are also described. Descriptions of the various deployment systems are given in Section 3 along with descriptions of the capabilities of the deployment systems. During the course of the development project 7 types of survey instruments were demonstrated with the Pipe Explorer{trademark} and are a part of the basic toolbox of instruments available for use with the system. These survey tools are described in Section 4 along with their typical performance specifications. The 4 demonstrations of the system are described chronologically in Section 5. The report concludes with a summary of the history, status, and future of the Pipe Explorer{trademark} system in Section 6.

Cremer, C.D.; Kendrick, D.T.; Lowry, W.; Cramer, E.

1997-09-30

247

A Sensitivity-Based Design Space Exploration Methodology for Embedded Systems  

Microsoft Academic Search

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

WILLIAM FORNACIARI; DONATELLA SCIUTO; CRISTINA SILVANO; VITTORIO ZACCARIA

2002-01-01

248

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

249

Earth Exploration Toolbook: Step-by-Step Guides for Investigating Earth System Data  

NSDL National Science Digital Library

The Earth Exploration Toolbook (EET) is a collection of step-by-step examples, called chapters, of the use of Earth system science resources in an educational context for the educational community. The resources include datasets, analysis tools, visualization tools, and other educational products. Each chapter features one specific resource. The chapters provide the non-expert teacher/educator with enough experience and in-depth knowledge of the featured resource to be able to use it in other contexts, and to help their students use the resource to explore and investigate issues in Earth system science. The purpose of the Earth Exploration Toolbook is to support the use of scientific datasets, tools, and other products developed and archived for the scientific community by the broader educational community.

2003-09-02

250

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

251

Acoustic emissions (AE) monitoring of large-scale composite bridge components  

NASA Astrophysics Data System (ADS)

Acoustic Emissions (AE) has been successfully used with composite structures to both locate and give a measure of damage accumulation. The current experimental study uses AE to monitor large-scale composite modular bridge components. The components consist of a carbon/epoxy beam structure as well as a composite to metallic bonded/bolted joint. The bonded joints consist of double lap aluminum splice plates bonded and bolted to carbon/epoxy laminates representing the tension rail of a beam. The AE system is used to monitor the bridge component during failure loading to assess the failure progression and using time of arrival to give insight into the origins of the failures. Also, a feature in the AE data called Cumulative Acoustic Emission counts (CAE) is used to give an estimate of the severity and rate of damage accumulation. For the bolted/bonded joints, the AE data is used to interpret the source and location of damage that induced failure in the joint. These results are used to investigate the use of bolts in conjunction with the bonded joint. A description of each of the components (beam and joint) is given with AE results. A summary of lessons learned for AE testing of large composite structures as well as insight into failure progression and location is presented.

Velazquez, E.; Klein, D. J.; Robinson, M. J.; Kosmatka, J. B.

2008-04-01

252

Successfully Attacking Masked AES Hardware Implementations  

Microsoft Academic Search

http:\\/\\/www.iaik.TUGraz.at\\/research\\/sca-lab Abstract. During the last years, several masking schemes for AES have been proposed to secure hardware implementations against DPA attacks. In order to investigate the effectiveness of these countermeasures in prac- tice, we have designed and manufactured an ASIC. The chip features an unmasked and two masked AES-128 encryption engines that can be at- tacked independently. In addition to

Stefan Mangard; Norbert Pramstaller; Elisabeth Oswald

2005-01-01

253

Revolutionary Design for Astronaut Exploration - Beyond the Bio-Suit System  

NASA Astrophysics Data System (ADS)

The Bio-Suit System is designed to revolutionize human space exploration by providing enhanced astronaut extravehicular activity (EVA) locomotion and performance based on the concepts of a `second skin' capability. The novel Bio-Suit concept provides an overall exploration system realized through symbiotic relationships between a suite of advanced technologies, creative design, human modeling and analysis, and new mission operations techniques. By working at the intersection of engineering, design, life sciences and operations, new emergent capabilities and interrelationships result for applications to space missions, medical rehabilitation, and extreme sports activities. In many respects, the Bio-Suit System mimics Nature (biomimetics). For example, the second skin is capable of augmenting our biological skin by providing mechanical counter-pressure. We have designed and tested prototypes that prove mechanical counter-pressure feasibility. The `epidermis' of our second skin suit is patterned from 3D laser scans that incorporate human skin strain field maps for maximum mobility and natural movements, while requiring minimum energy expenditure for exploration tasks. We provide a technology roadmap for future design, pressure production and technology investments for the Bio-Suit System. Woven into the second skin are active materials to enhance human performance as well as to provide necessary performance metrics (i.e., energy expenditure). Wearable technologies will be embedded throughout the Bio-Suit System to place the explorer in an information-rich environment enabling real-time mission planning, prediction, and visualization. The Bio-Suit System concept augments human capabilities by coupling human and robotic abilities into a hybrid of the two, to the point where the explorer is hardly aware of the boundary between innate human performance and robotic activities.

Newman, Dava J.; Canina, Marita; Trotti, Guillermo L.

2007-01-01

254

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

255

Unlocking the Black Box: Exploring the Link between High-Performance Work Systems and Performance  

ERIC Educational Resources Information Center

With a growing body of literature linking systems of high-performance work practices to organizational performance outcomes, recent research has pushed for examinations of the underlying mechanisms that enable this connection. In this study, based on a large sample of Welsh public-sector employees, we explored the role of several individual-level

Messersmith, Jake G.; Patel, Pankaj C.; Lepak, David P.

2011-01-01

256

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

Microsoft Academic Search

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

Lukai Cai; Andreas Gerstlauer; Daniel Gajski

2004-01-01

257

Effects of climate change on moose populations: Exploring the response horizon through biometric and systems models  

Microsoft Academic Search

Interest in the response of moose to climate change has increased because of the potential role they play in the conservation of woodland caribou, and threatened loss to recreational and economic opportunities. The objective of this study is to develop a plausible, parsimonious, systems-level model of moose population dynamics that will be useful in exploring the response of moose populations

Robert S. Rempel

2011-01-01

258

Preliminary system analysis of in situ resource utilization for Mars human exploration  

Microsoft Academic Search

We carried out a system analysis of processes for utilization of Mars resources to support human exploration of Mars by production of propellants and life-support consumables from indigenous resources. Seven ISRU processes were analyzed to determine mass, power and propellant storage volume requirements. The major elements of each process include CO2 acquisition, chemical conversion, and storage of propellants. Based on

Donald Rapp; Jason Andringa; Robert Easter; Jeffrey H. Smith; Thomas J. Wilson; D. Larry Clark; Kevin Payne

2005-01-01

259

A computer-assisted learning system for exploring geometry conjectures online  

Microsoft Academic Search

We believe it would be fun and meaningful for students to make geometric conjectures and experience the joy of mathematical inquiry by manipulating dynamic geometry figures in a system we have designed. In order to facilitate the students to explore geometric conjectures, we have designed tools for constructing geometric objects, measurement tools, and tools to construct geometric conjectures. In an

Wing-Kwong WONG; Chang-Zhe YANG; Sheng-Kai YIN

260

Bioinspired Engineering of Exploration Systems for NASA and DoD  

Microsoft Academic Search

A new approach called bioinspired engineering of exploration systems (BEES) and its value for solving pressing NASA and DoD needs are described. Insects (for example honeybees and dragonflies) cope remarkably well with their world, despite possessing a brain containing less than 0.01% as many neurons as the human brain. Although most insects have immobile eyes with fixed focus optics and

Sarita Thakoor; Javaan Chahl; M. V. Srinivasan; L. Young; Frank Werblin; Butler Hine; Steven Zornetzer

2003-01-01

261

Bioinspired Engineering of Exploration Systems for NASA and DoD  

Microsoft Academic Search

A new approach called bioinspired engineering of exploration systems (BEES) and its value for solving pressing NASA and DoD needs are described. Insects (for example honeybees and dragonflies) cope remarkably well with their world, despite possessing a brain containing less than 0.01%% as many neurons as the human brain. Although most insects have immobile eyes with fixed focus optics and

Sarita Thakoor; Javaan S. Chahl; Mandyam V. Srinivasan; L. Young; Frank Werblin; Butler Hine; Steven Zornetzer

2002-01-01

262

Exploring The Impact of The Media on the Arranged Marriage and Dowry System in Goa, India  

Microsoft Academic Search

Indian women have been experiencing the arranged marriage and dowry system for centuries. The main objective of this study was to explore how television and cinematic programming impact tehse traditional and contextual issues. I used a phenomenological-hermeneutic research methodology, with a feminist pragmatist epistemology. I conducted a total of six personal inteviews with Hindu women from Goa, India. Three participants

Lisa Ann Hickman

2007-01-01

263

Classroom Response Systems: Using Task Technology Fit to Explore Impact Potential  

ERIC Educational Resources Information Center

|The primary purpose of this study is to determine how students are impacted by the use of Classroom Response System (CRS) technology. This research explores the nature of the outcomes experienced by students and their perceptions on the leading pedagogy and practices for using CRS technology in the classroom. The research is both quantitative and

Jones, Kenneth D., II.

2010-01-01

264

Multiple Embedded Inequalities and Cultural Diversity in Educational Systems: A Theoretical and Empirical Exploration  

ERIC Educational Resources Information Center

This article explores the social construction of cultural diversity in education, with a view to social justice. It examines how educational systems organize ethno-cultural difference and how this process contributes to inequalities. Theoretical resources are drawn from social philosophy as well as from recent developments in social organisation

Verhoeven, Marie

2011-01-01

265

Japanese future plans for exploration of primitive bodies in the solar system  

Microsoft Academic Search

More than two years has passed since the exploration of Itokawa by Hayabusa spacecraft. For the first time, we saw real appearance of a very small solar system body, whose size is only about 500 m in length. We had a lot of scientific results form the observation of Hayabusa, and we got many clues to know the origin and

Makoto Yoshikawa; Hajime Yano; Junichiro Kawaguchi

2008-01-01

266

Unlocking the Black Box: Exploring the Link between High-Performance Work Systems and Performance  

ERIC Educational Resources Information Center

|With a growing body of literature linking systems of high-performance work practices to organizational performance outcomes, recent research has pushed for examinations of the underlying mechanisms that enable this connection. In this study, based on a large sample of Welsh public-sector employees, we explored the role of several individual-level

Messersmith, Jake G.; Patel, Pankaj C.; Lepak, David P.

2011-01-01

267

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

268

GEOTHERMAL SYSTEMS ASSESSMENTIDENTIFICATION AND MITIGATION OF EGS EXPLORATION RISK  

Microsoft Academic Search

The conventional view in Australia (and many other places) is that achieving optimal temperature is the critical risk in exploration for conductive geothermal resources. This view has often resulted in other areas of risk being overlooked. A Geothermal Systems Assessment (GSA) investigates and ranks four largely independent critical risk areasheat source, thermal\\/hydraulic insulation, reservoir potential, and working fluid. These four

Graeme R Beardsmore; Gareth T Cooper

269

Teachers, narrative identity and ability constructs: exploring dissonance and consensus in contrasting school systems  

Microsoft Academic Search

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, drawing on dynamic concepts of identity, consideration was given to the ways in which teachers in

Lorna Christine Hamilton

2010-01-01

270

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

271

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.

272

Analysis and Design of a Capsule Landing System and Surface Vehicle Control System for Mars Exploration.  

National Technical Information Service (NTIS)

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, ...

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

1977-01-01

273

System-Level Bus-Based Communication Architecture Exploration Using a Pseudoparallel Algorithm  

Microsoft Academic Search

Growing complexity in system-on-a-chip (SoC) design demands effective approaches to explore various architectures quickly for the target applications. With the common use of intellectual properties (IPs) in SoC and the large amount of data interchanges among IPs, communication architecture significantly affects the system in terms of power and performance. Therefore, designers should carefully plan the communication architecture to meet the

Lih-Yih Chiou; Yi-Siou Chen; Chih-Hsien Lee

2009-01-01

274

System-level architectural exploration using allocation-on-demand technique  

Microsoft Academic Search

Architectural exploration is very important in embedded system design and SoC design. In this paper, a new heuristic algorithm using the allocation-on-demand technique is proposed to solve this problem. Unlike previous research efforts, this algorithm allocates new resources only when it fails to schedule tasks under the performance constraints. So the resource costs of the system increase monotonously in running,

Qiang Wu; Jinian Bian; Hongxi Xue

2005-01-01

275

Exploration of clinical pharmacist management system and working model in China  

Microsoft Academic Search

This manuscript is intended to explore and establish a management system and working model which can maximise the development\\u000a of clinical pharmacy in China. With a study of a series of documents about clinical pharmacists issued by China Ministry of\\u000a Health and practical experience in clinical pharmacist training, the authors have reached the conclusion that the management\\u000a system and working

Man Zhu; Dai-Hong Guo; Gui-Yang Liu; Fei Pei; Bo Wang; Dong-Xiao Wang; Wei-Lan Wang; Cui-Li Huang

2010-01-01

276

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

Microsoft Academic Search

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

N. Harada; C. Buttapeng

2004-01-01

277

a Carbon Dioxide Collection and Pressure Generation Breadboard System for Mars Exploration  

Microsoft Academic Search

In the framework of development programs for future European Space Agency (ESA) missions aimed at Mars exploration, a breadboard propulsion system has been developed at Commissariat l'Energie Atomique (CEA-INAC\\/SBT). The objective is to design a system that can produce a thrust sufficient to move the whole device on the planet surface. In order to reduce the cost and the

Ph. Gully; E. Ercolani; L. Guillemet; A. Sirbi; M. Linder

2010-01-01

278

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

279

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

280

Integrated Design of AES (Advanced Encryption Standard) Encrypter and Decrypter  

Microsoft Academic Search

This paper proposed a method of integrating the AES encrypter and the AES decrypter into a full functional AES crypto-engine. This method can make it a very low-complexity architecture, especially in saving the hardware resource in implementing the AES (Inv)SubBytes module and (Inv)Mixcolumns module, etc. Most designed modules can be used for both AES encryption and decryption. Besides, the architecture

Chih-chung Lu; Shau-yin Tseng

2002-01-01

281

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

NASA Astrophysics Data System (ADS)

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

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

2008-11-01

282

Diagnostic expert systems: Encoding geological knowledge for an exploration play analysis  

SciTech Connect

The U.S. Geological Survey is currently exploring the feasibility of applying diagnostic expert systems and knowledge-based acquisition techniques to the geologic analysis of sedimentary basins and petroleum exploration plays. This paper describes a unique approach to the design and application of a rule-based expert system to the analysis of exploration plays, a methodology commonly used to assess petroleum resources in a basin. This technique consists of using various geologic models and Monte Carlo simulation or probabilistic methods for analyzing geologic and reservoir conditions favorable to the occurrence of petroleum resources. Work is in progress to adapt the geologic model used in the play analysis to an expert-systems and knowledge base, the object being to capture the logic and reasoning used to characterize the geologic model and to evaluate the play. Expert systems techniques now being developed are capable of dealing with inexact reasoning or reasoning under uncertainty by incorporating degrees of uncertainty to deal effectively with incomplete, inferred, or interpretive data involved in the knowledge base. The goal of this study is to provide an embedded diagnostic expert-system approach for characterizing the geologic model to expand upon the play-analysis system. Such a system provides the geologist with capabilities to document major basin components, such as stratigraphy, structural geology, and sedimentation, and to analyze the traditional concepts of source, reservoir, and trapping mechanisms. This expert system will assist the geologist in compiling and interpreting the geologic and reservoir engineering data necessary for running the probabilistic methods to calculate the amount of probable petroleum resources within each play. Diagnostic expert-systems technology can provide challenging new tools in knowledge acquisition and data interpretation in petroleum geology.

Miller, B.M. (Geological Survey, Denver, CO (United States))

1993-08-01

283

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

NASA Astrophysics Data System (ADS)

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.

1994-03-01

284

Realization and optimization of AES algorithm on the TMS320DM6446 based on DaVinci technology  

NASA Astrophysics Data System (ADS)

The application of AES algorithm in the digital cinema system avoids video data to be illegal theft or malicious tampering, and solves its security problems. At the same time, in order to meet the requirements of the real-time, scene and transparent encryption of high-speed data streams of audio and video in the information security field, through the in-depth analysis of AES algorithm principle, based on the hardware platform of TMS320DM6446, with the software framework structure of DaVinci, this paper proposes the specific realization methods of AES algorithm in digital video system and its optimization solutions. The test results show digital movies encrypted by AES128 can not play normally, which ensures the security of digital movies. Through the comparison of the performance of AES128 algorithm before optimization and after, the correctness and validity of improved algorithm is verified.

Jia, Wen-bin; Xiao, Fu-hai

2013-03-01

285

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

286

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

Microsoft Academic Search

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

Ireneusz Karkowski; Henk Corporaal

1998-01-01

287

An alternative approach to solar system exploration providing safety of human mission to Mars  

Microsoft Academic Search

For systematic human Mars exploration, meeting crew safety requirements, it seems perspective to assemble into a spacecraft: an electrical rocket, a well-shielded long-term life support system, and a manipulator-robots operating in combined presence effect and master-slave mode. The electrical spacecraft would carry humans to the orbit of Mars, providing short distance (and low signal time delay) between operator and robot-manipulators,

J. I. Gitelson; S. I. Bartsev; V. V. Mezhevikin; V. A. Okhonin

2003-01-01

288

Directed Evolution: A Historical Exploration into an Evolutionary Experimental System of Nanobiotechnology, 19652006  

Microsoft Academic Search

This study explores the history of nanotechnology from the perspective of protein engineering, which differs from the history\\u000a of nanotechnology that has arisen from mechanical and materials engineering; it also demonstrates points of convergence between\\u000a the two. Focusing on directed evolutionan experimental system of molecular biomimetics that mimics nature as an inspiration\\u000a for material designthis study follows the emergence of

Eun-Sung Kim

2008-01-01

289

Social Acceptance of Negotiation Support Systems: Scenario-based Exploration with Focus Groups and Online Survey  

Microsoft Academic Search

We investigate people{\\\\textquoteright}s attitudes toward the possible use of negotiation support systems (NSS) in different social contexts and the consequences for their design. To explore functional requirements and social acceptance in different use contexts, we followed a three-step approach. In the first step, we conducted a number of focus groups with negotiation experts. Second, we conducted focus groups with potential

Alina Pommeranz; Pascal Wiggers; Willem-Paul Brinkman; Catholijn M. Jonker

2011-01-01

290

Concepts for future exploration for submarine fan and turbidite system reservoirs  

SciTech Connect

With the emphasis of future petroleum exploration in deeper water and on frontier plays, submarine fan and turbidite systems will be major reservoir targets. Successful exploration and development of these reservoirs will be largely controlled by world oil prices, politics, markets, and drilling and producing technologies. Present economics require large reserves when targeting deep water or when drilling remote regions of countries that require large capital expenditures for pipelines and development. Future techniques for successful exploration and production of turbidite reservoirs will include (1) successful application of sequence stratigraphy in identifying reservoirs, (2) new play concepts for exploring synclinal low areas, and (3) the expanded use of three-dimensional seismic surveys. Lacustrine turbidites in rift, wrench, and successor basins are good potential targets because of their association with good source rocks/seals. Reservoirs occur at the base of deltaic clinoforms interbedded with source locks or along actively subsiding fault scarps. Many of these basins are extremely large, but the distribution of source rocks may be limited, making the potential reserves in these systems highly variable. Submarine fans associated with Cenozoic deltas remain an active deep water play. Turbidite reservoirs, deposited within bathymetric lows and localized basins on the slope created by salt and shale diapirism, occur in areas such as the northern Gulf of Mexico, continental margin of Nigeria, and Mackenzie Delta/Canadian Beaufort Sea. Other prospective Cenozoic delta-related margins include those associated with the Amazon, Indus, Ganges-Bramapuhtra, and Mahakam Deltas. The tremendous exploration successes in the deep-water Campos basin illustrate the great potential in passive margins. Targets are subtle and influenced by depositional topography controlled by growth faults, and shale and salt diapirs.

Link, M.H.; Weimer, P. (Mobil Research and Development, Dallas, TX (USA))

1990-05-01

291

Japanese future plans for exploration of primitive bodies in the solar system  

NASA Astrophysics Data System (ADS)

More than two years has passed since the exploration of Itokawa by Hayabusa spacecraft. For the first time, we saw real appearance of a very small solar system body, whose size is only about 500 m in length. We had a lot of scientific results form the observation of Hayabusa, and we got many clues to know the origin and evolution of the solar system. As working for Hayabusa, we have also considered post-Hayabusa missions. Since the Itokawa is an S-type asteroid, next target should be a C-type asteroid, because these two types are abundant in the main asteroid belt. The next mission to Hayabusa is 'Hayabusa-2', which will explore C-type asteroid. The spacecraft is quite similar to Hayabusa, so we can save time for manufacturing it. The current target asteroid of Hayabusa-2 is 1999 JU3, which is intensively observed in 2007 and 2008. At the same time, we were also considering much more advanced mission after Hayabusa-2, and this mission is called 'Hayabusa-Mk2.' The target of Hayabusa-Mk2 should be much more primitive objects such as P-type or D-type asteroids, CAT, and comets, and the spacecraft is a newly developed one. In this way, we (=JAXA) are considering programmatic missions for the exploration of primitive bodies. Since there are many small bodies in the solar system, we should have such strategic approach. From 2006, Hayabusa-Mk2 is also considered under the scheme of Cosmic Vision of ESA with the European study group for small bodies of the solar system. And it was proposed to Cosmic Vision with the name of 'Marco Polo.' It has passed the first selection so now we are in the assessment phase. The spacecraft, for which Japan is responsible, is based on the idea of Hayabusa-Mk2, but we reconsider it to have a large lander and a new sampling system from Europe. There are four principal purposes for asteroid exploration, that is, science, spaceguard, resources, and manned mission. The science is the main target and we want to know the origin and evolution of the solar system and the life. And now, the other purposes, spaceguard and resources, are becoming important, too. Moreover Near Earth Asteroids are now considered as good targets for manned missions after the Moon but before Mars. The long-ranged exploration plan and international collaborations will be more important from now on.

Yoshikawa, Makoto; Yano, Hajime; Kawaguchi, Junichiro

292

Design Space Exploration and System Optimization with SymTA\\/S-- Symbolic Timing Analysis for Systems  

Microsoft Academic Search

The increasing complexity of heterogeneous SoC and distributed systems confronts the system designer with problems how to determine reasonable design alternatives leading to well functioning systems. Ideally, a designer would try all possible system configuration and choose the best one regarding specific system requirements. Unfortu- nately, such an approach is not possible because the high number of design parameters in

Arne Hamann; Marek Jersak; Kai Richter; Rolf Ernst

2004-01-01

293

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

2013-09-01

294

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 bodys 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

295

Characterization of radioactive contamination inside pipes with the Pipe Explorer{trademark} system  

SciTech Connect

The U.S. Department of Energy`s nuclear facility decommissioning program needs to characterize radiological contamination inside piping systems before the pipe can be recycled, remediated, or disposed. Science and Engineering associates, Inc. under contract with the DOE Morgantown Energy Technology Center has developed and demonstrated the Pipe Explorer{trademark} system, which uses an inverting membrane to transport various characterization sensors into pipes. The basic process involves inverting (turning inside out) a tubular impermeable membrane under air pressure. A characterization sensor is towed down the interior of the pipe by the membrane. Advantages of this approach include the capability of deploying through constrictions in the pipe, around 90{degrees} bends, vertically up and down, and in slippery conditions. Because the detector is transported inside the membrane (which is inexpensive and disposable), it is protected from contamination, which eliminates cross-contamination. Characterization sensors that have been demonstrated with the system thus far include: gamma detectors, beta detectors, video cameras, and pipe locators. Alpha measurement capability is currently under development. A remotely operable Pipe Explorer{trademark} system has been developed and demonstrated for use in DOE facilities in the decommissioning stage. The system is capable of deployment in pipes as small as 2-inch-diameter and up to 250 feet long. This paper describes the technology and presents measurement results of a field demonstration conducted with the Pipe Explorer{trademark} system at a DOE site. These measurements identify surface activity levels of U-238 contamination as a function of location in drain lines. Cost savings to the DOE of approximately $1.5 million dollars were realized from this one demonstration.

Kendrick, D.T.; Cremer, C.D.; Lowry, W.; Cramer, E.

1995-12-31

296

Information Exploration System for Sickle Cell Disease and Repurposing of Hydroxyfasudil  

PubMed Central

Background Sickle cell disease (SCD) is a fatal monogenic disorder with no effective cure and thus high rates of morbidity and sequelae. Efforts toward discovery of disease modifying drugs and curative strategies can be augmented by leveraging the plethora of information contained in available biomedical literature. To facilitate research in this direction we have developed a resource, Dragon Exploration System for Sickle Cell Disease (DESSCD) (http://cbrc.kaust.edu.sa/desscd/) that aims to promote the easy exploration of SCD-related data. Description The Dragon Exploration System (DES), developed based on text mining and complemented by data mining, processed 419,612 MEDLINE abstracts retrieved from a PubMed query using SCD-related keywords. The processed SCD-related data has been made available via the DESSCD web query interface that enables: a/information retrieval using specified concepts, keywords and phrases, and b/the generation of inferred association networks and hypotheses. The usefulness of the system is demonstrated by: a/reproducing a known scientific fact, the Sickle_Cell_AnemiaHydroxyurea association, and b/generating novel and plausible Sickle_Cell_AnemiaHydroxyfasudil hypothesis. A PCT patent (PCT/US12/55042) has been filed for the latter drug repurposing for SCD treatment. Conclusion We developed the DESSCD resource dedicated to exploration of text-mined and data-mined information about SCD. No similar SCD-related resource exists. Thus, we anticipate that DESSCD will serve as a valuable tool for physicians and researchers interested in SCD.

Essack, Magbubah; Radovanovic, Aleksandar; Bajic, Vladimir B.

2013-01-01

297

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 demonstratorsa Mars Lander and a Lunar Roverfit 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

298

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

PubMed

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. PMID:15806749

Mendell, W W; Heydorn, R P

299

Nuclear Electric Propulsion: A ``Better, Safer, Cheaper'' Transportation System for Human Exploration of Mars  

NASA Astrophysics Data System (ADS)

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 large cost savings! 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) 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. Non-nuclear technology development for the NEP system is estimated to cost about $721 M (1993 $). Nuclear technology development costs are not included in the costs in this report, since these costs will be incurred in the nuclear surface power development program. NEP Phase A/B studies are estimated to cost about $154 M. Flight system hardware development (Phase C/D) is estimated to cost about $2.8 B, and fabrication of flight hardware is estimated to be about $7.8 B for four mission opportunities in 2009, 2011, 2014, and 2016.

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

1994-07-01

300

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 intellectualall 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

301

Early Devonian geothermal systems in northeast Scotland: Exploration targets for epithermal gold  

SciTech Connect

Early Devonian geothermal activity is recognized in northeast Scotland by the remnants of silica sinter, a hot-spring manganese deposit, an area of steam alteration, and hydrothermal eruption breccias. At least five systems were active at this time, three of which are located on or near the intersection of major faults and lineaments. Two deposits can be dated as Early Devonian, whereas others show a spatial relation to 408 Ma Caledonian granitoids-the proposed heat sources for the geothermal systems. Fault zones active at this time provided channelways for fluids in the convecting systems. The shallow sections of these systems have been preserved in the Arndilly, Dalroy, Lecht, and Rhynie areas, which is encouraging for gold prospecting. Six targets for epithermal gold exploration are identified: the four areas named above and two areas at the intersection of major faults and lineaments.

Nicholson, K. (Univ. of Auckland, Private Bag (New Zealand))

1989-06-01

302

The Geologist's Field Assistant: Developing an Innovative Science Analysis System for Exploring the Surface of Mars  

NASA Astrophysics Data System (ADS)

We are developing science analysis algorithms to interface with a Geologist's Field Assistant (GFA) device that will allow robotic or human remote explorers to better sense and explore their surroundings during limited surface excursions. Our algorithms will interpret spectral and imaging data obtained by various sensors. The algorithms, for example, will identify key minerals, rocks, and sediments from mid-IR, Raman, and visible/near-IR spectra as well as from high-resolution and microscopic images to help interpret data and to provide high-level advice to the remote explorer. A key task for human or robotic explorers on the surface of Mars is choosing which particular rock or mineral samples should be selected for more intensive study. The usual challenges of such a task are compounded by the lack of sensory input available to a suited astronaut or the limited downlink bandwidth available to a rover. Additional challenges facing a human mission include limited surface time and the similarities in appearance of important minerals (e.g. carbonates, silicates, salts). Yet the choice of which sample to collect is critical. A top-level system allows multiple inputs from raw sensor data output by imagers and spectrometers (visible/near-IR, mid-IR, and Raman) as well as human opinion to identify rock and mineral samples. Our prototype image analysis system identifies some igneous and metamorphic rocks from texture and color information. Spectral analysis algorithms have also been developed that successfully identifiy quartz, silica polymorphs, calcite, pyroxene, and jarosite from both visible/near-IR and mid-IR spectra. We have also developed spectral recognizers that identify high-iron pyroxenes and iron-bearing minerals using visible/near-IR spectra only. We are building a combined image and spectral database of rocks and minerals with which to continue development of our algorithms. Future plans include developing algorithms to identify key igneous, sedimentary, and some metamorphic rocks.

Gulick, V. C.; Morris, R. L.; Gazis, P. R.; Bishop, J. L.; Alena, R. L.

2002-12-01

303

Performance Comparison of the AES Submissions  

Microsoft Academic Search

The principal goal guiding the design of any encryption algorithm must be security. In the real world, however, performance and implementation cost are always of concern. Making the assumption that the major AES candidates are secure (a big assumption, to be sure, but one that is best dealt with in another paper), the most important properties the algorithms will be

Bruce Schneier; John Kelsey; Doug Whiting; David Wagner; Chris Hall; Niels Ferguson

1999-01-01

304

Cache-timing attacks on AES  

Microsoft Academic Search

This paper warns against the use of S-boxes in cryptography. In particular, this paper shows that a simple cache-timing attack against AES software reveals some key bits; this paper also discusses some of the obstacles to constant-time array access on modern CPUs.

Daniel J. Bernstein

2005-01-01

305

Advanced AE Techniques in Composite Materials Research  

Microsoft Academic Search

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

William H. Prosser

1996-01-01

306

Exploration of two-enzyme coupled catalysis system using scanning electrochemical microscopy.  

PubMed

In biological metabolism, a given metabolic process usually occurs via a group of enzymes working together in sequential pathways. To explore the metabolism mechanism requires the understanding of the multienzyme coupled catalysis systems. In this paper, an approach has been proposed to study the kinetics of a two-enzyme coupled reaction using SECM combining numerical simulations. Acetylcholine esterase and choline oxidase are immobilized on cysteamine self-assembled monolayers on tip and substrate gold electrodes of SECM via electrostatic interactions, respectively. The reaction kinetics of this two-enzyme coupled system upon various separation distance precisely regulated by SECM are measured. An overall apparent Michaelis-Menten constant of this enzyme cascade is thus measured as 2.97 mM at an optimal tip-substrate gap distance of 18 ?m. Then, a kinetic model of this enzyme cascade is established for evaluating the kinetic parameters of individual enzyme by using the finite element method. The simulated results demonstrate the choline oxidase catalytic reaction is the rate determining step of this enzyme cascade. The Michaelis-Menten constant of acetylcholine esterase is evaluated as 1.8 mM. This study offers a promising approach to exploring mechanism of other two-enzyme coupled reactions in biological system and would promote the development of biosensors and enzyme-based logic systems. PMID:23181438

Wu, Zeng-Qiang; Jia, Wen-Zhi; Wang, Kang; Xu, Jing-Juan; Chen, Hong-Yuan; Xia, Xing-Hua

2012-12-03

307

Age distributions and dynamically changing hydrologic systems: Exploring topography-driven flow  

NASA Astrophysics Data System (ADS)

Natural systems are driven by dynamic forcings that change in time as well as space, behavior that is inherited by the system flow field and results in time-varying age distributions (ADs). This work presents a review of the mathematical tools and solution approaches used to model ADs in dynamic time-varying flow systems. A simple conceptual, numerical model is then used to explore the role of flow dynamics in ADs for topography-driven flow systems. This model is an analog for regional groundwater systems and hyporheic zones. This model demonstrates that relatively small fluctuations in the forcing, even though importantly affecting the flow in the system, can have minimal effects in ADs. However, as the intensity of fluctuation increases, still within the bounds observed in natural systems, ADs in shallow parts of the system become highly sensitive to dynamic flow conditions, leading to considerable changes in the moments and modality of the distributions with time. In particular, transient flow can lead to emergence of new modes in the AD, which would not be present under steady flow conditions. The discrepancy observed between ADs under steady and transient flow conditions is explained by enhancement of mixing due to temporal variations in the flow field. ADs in deeper parts of the system are characterized by multimodality and tend to be more stable over time even for large forcing fluctuations.

Gomez, J. D.; Wilson, J. L.

2013-03-01

308

Developmental Systems Science: Exploring the Application of Systems Science Methods to Developmental Science Questions  

Microsoft Academic Search

Developmental science theorists fully acknowledge the wide array of complex interactions among biology, behavior, and environment that together give rise to development. However, despite this conceptual understanding of development as a system, developmental science has not fully applied analytic methods commensurate with this systems perspective. This article provides a brief introduction to systems science, an approach to problem solving that

Jennifer Brown Urban; Nathaniel D. Osgood; Patricia L. Mabry

2011-01-01

309

Directed-polymer systems explored via their quantum analogs: General polymer interactions and their consequences  

NASA Astrophysics Data System (ADS)

The impact of polymer-polymer interactions of various types on the thermodynamics, structure, and accommodation of topological constraints is addressed for systems comprising many directed polymers in two spatial dimensions. The approach is predicated on the well-known equivalence between the classical equilibrium statistical mechanics of directed polymers in two spatial dimensions and the imaginary-time quantum dynamics of particles in one spatial dimension, originally exploited by P.-G. de Gennes [P.-G. de Gennes, J. Chem. Phys.JCPSA60021-960610.1063/1.1669420 48, 2257 (1968)]. Known results concerning two exactly solvable microscopic models of quantum particles moving in one spatial dimensionthe Lieb-Liniger model of contact interactions and the Calogero-Sutherland model of long-range interactionsare used to shed light on the behavior of the corresponding polymeric systems. In addition, the technique of bosonization is used to reveal how generic polymer interactions give rise to an emergent polymer fluid that has universal collective excitations. Additionally, the response of the system to topological constraints such as pins though which polymers cannot pass is explored. Immediately on the compressed side of a pin there is a divergent pile-up in polymer density, while on the other side there is a gap of finite area in which polymer density is negligible. Comparison of this response to that of a system of simply noncrossing (i.e., noncrossing but otherwise noninteracting) directed polymers, explored in a companion paper, reveals that generic interactions leave the structure quantitatively unchanged on the line transverse to the pin, and leave it qualitatively unchanged throughout the two dimensions of the system's extent. Furthermore, the free-energy cost associated with a pin that partitions a system having generic interactions is found to be proportional to the pin-partitioning cost for a system of simply noncrossing polymers.

Rocklin, D. Zeb; Goldbart, Paul M.

2013-10-01

310

Rheological Properties and Morphology of PC\\/AES Blends  

Microsoft Academic Search

Blends of polycarbonate (PC) and acrylonitrileEPDM (ethylene\\/propylene\\/diene elastomer)styrene terpolymer (AES) were prepared at 20%, 30%, 40%, 50%, and 80% by weight of AES. The rheological properties and morphology of the PC, AES, and their blends were studied systematically. The strain sweep results show that the linear viscoelastic region of the AES is far less than that of PC. With the

Bo Liu; Yong Zhang; Chaoying Wan; Wenjuan Shou; Yinxi Zhang; Yu Su; Jiliang Ji

2006-01-01

311

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

312

Exploring clinician adoption of a novel evidence request feature in an electronic medical record system  

PubMed Central

Objective: The research evaluated strategies for facilitating physician adoption of an evidence-based medicine literature request feature recently integrated into an existing electronic medical record (EMR) system. Methods: This prospective study explored use of the service by 137 primary care physicians by using service usage statistics and focus group and survey components. The frequency of physicians' requests for literature via the EMR during a 10-month period was examined to explore the impact of several enhanced communication strategies launched mid-way through the observation period. A focus group and a 25-item survey explored physicians' experiences with the service. Results: There was no detectable difference in the proportion of physicians utilizing the service after implementation of the customized communication strategies (11% in each time period, P=1.0, McNemar's test). Forty-eight physicians (35%) responded to the survey. Respondents who had used the service (n=19) indicated that information provided through the service was highly relevant to clinical practice (mean rating 4.6, scale 1 not relevant5 highly relevant), and most (n=15) reported sharing the information with colleagues. Conclusion: The enhanced communication strategies, though well received, did not significantly affect use of the service. However, physicians noted the relevance and utility of librarian-summarized evidence from the literature, highlighting the potential benefits of providing expert librarian services in clinical workflow.

Jerome, Rebecca N.; Bettinsoli Giuse, Nunzia; Rosenbloom, S. Trent; Arbogast, Patrick G.

2008-01-01

313

Small space reactor power systems for unmanned solar system exploration missions  

Microsoft Academic Search

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

Harvey S. Bloomfield

1987-01-01

314

ASIP array system performance analysis and design space exploration using SystemC  

Microsoft Academic Search

In this paper we present a design methodology to address the allocation\\/scheduling problem of a given parallel application task precedence graph (TPG) to a multiprocessor architecture referred to as ASIP array system using SystemC simulation models. The basic rationale of the proposed method is to develop modeling constructs and library in SystemC to help designers automate the process of generation

Mohamed HASSAN; Etsuko OKUSHI; Masaharu IMAI

2007-01-01

315

Highly Survivable Avionics Systems for Long-Term Deep Space Exploration  

NASA Astrophysics Data System (ADS)

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

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

2001-01-01

316

The MagOrion-A propulsion system for human exploration of the outer planets  

NASA Astrophysics Data System (ADS)

Manned exploration beyond Mars requires very high specific energy. The only potential solution under discussion is fusion propulsion. However, fusion has been ten years away for forty years. We have an available solution that combines new technology with an old concept-``Project Orion.'' The proposed ``MagOrion'' Propulsion System combines a magnetic sail (MagSail) with conventional small yield (0.5 to 1.0 kiloton) shaped nuclear fission devices. At denonation, roughly eighty percent of the yield appears as a highly-ionized plasma, and when detonated two kilometers behind a robust MagSail, approximately half of this plasma can be stopped and turned into thrust. A MagOrion can provide a system acceleration of one or more gravities with effective specific impulses ranging from 15,000 to 45,000 seconds. Dana Andrews and Robert Zubrin published a paper in 1997 that described the operating principles of the MagOrion. We have taken that concept through conceptual design to identify the major operational features and risks. The risks are considerable, but the potential payoff is staggering. Our proposed MagOrion will enable affordable exploration of the solar system. .

Andrews, Jason; Andrews, Dana

2000-01-01

317

Characterization of pipes, drain lines, and ducts using the pipe explorer system  

SciTech Connect

As DOE dismantles its nuclear processing facilities, site managers must employ the best means of disposing or remediating hundreds of miles of potentially contaminated piping and duct work. Their interiors are difficult to access, and in many cases even the exteriors are inaccessible. Without adequate characterization, it must be assumed that the piping is contaminated, and the disposal cost of buried drain lines can be on the order of $1,200/ft and is often unnecessary as residual contamination levels often are below free release criteria. This paper describes the program to develop a solution to the problem of characterizing radioactive contamination in pipes. The technical approach and results of using the Pipe Explorer {trademark} system are presented. The heart of the system is SEA`s pressurized inverting membrane adapted to transport radiation detectors and other tools into pipes. It offers many benefits over other pipe inspection approaches. It has video and beta/gamma detection capabilities, and the need for alpha detection has been addressed through the development of the Alpha Explorer{trademark}. These systems have been used during various stages of decontamination and decommissioning of DOE sites, including the ANL CP-5 reactor D&D. Future improvements and extensions of their capabilities are discussed.

Cremer, C.D.; Kendrick, D.T.; Cramer, E.

1997-05-01

318

Rapid Cl-/HCOFormula exchange kinetics of AE1 in HEK293 cells and hereditary stomatocytosis red blood cells.  

PubMed

Anion exchanger 1 (AE1) or band 3 is a membrane protein responsible for the rapid exchange of chloride for bicarbonate across the red blood cell membrane. Nine mutations leading to single amino-acid substitutions in the transmembrane domain of AE1 are associated with dominant hereditary stomatocytosis, monovalent cation leaks, and reduced anion exchange activity. We set up a stopped-flow spectrofluorometry assay coupled with flow cytometry to investigate the anion transport and membrane expression characteristics of wild-type recombinant AE1 in HEK293 cells, using an inducible expression system. Likewise, study of three stomatocytosis-associated mutations (R730C, E758K, and G796R), allowed the validation of our method. Measurement of the rapid and specific chloride/bicarbonate exchange by surface expressed AE1 showed that E758K mutant was fully active compared with wild-type (WT) AE1, whereas R730C and G796R mutants were inactive, reinforcing previously reported data on other experimental models. Stopped-flow analysis of AE1 transport activity in red blood cell ghost preparations revealed a 50% reduction of G796R compared with WT AE1 corresponding to a loss of function of the G796R mutated protein, in accordance with the heterozygous status of the AE1 variant patients. In conclusion, stopped-flow led to measurement of rapid transport kinetics using the natural substrate for AE1 and, conjugated with flow cytometry, allowed a reliable correlation of chloride/bicarbonate exchange to surface expression of AE1, both in recombinant cells and ghosts and therefore a fine comparison of function between different stomatocytosis samples. This technical approach thus provides significant improvements in anion exchange analysis in red blood cells. PMID:23842529

Frumence, Etienne; Genetet, Sandrine; Ripoche, Pierre; Iolascon, Achille; Andolfo, Immacolata; Le Van Kim, Caroline; Colin, Yves; Mouro-Chanteloup, Isabelle; Lopez, Claude

2013-07-10

319

Using an immune system model to explore mate selection in genetic algorithms.  

SciTech Connect

In the setting of multimodal function optimization, engineering and machine learning, identifying multiple peaks and maintaining subpopulations of the search space are two central themes when Genetic Algorithms (GAs) are employed. In this paper, an immune system model is adopted to develop a framework for exploring the role of mate selection in GAs with respect to these two issues. The experimental results reported in the paper will shed more light into how mate selection schemes compare to traditional selection schemes. In particular, we show that dissimilar mating is beneficial in identifying multiple peaks, yet harmful in maintaining subpopulations of the search space.

Huang, C. F. (Chien-Feng)

2003-01-01

320

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

321

Validation of an Advanced Encryption Standard (AES) IP Core  

Microsoft Academic Search

This paper describes the package of test bench code required to verify the Algotronix' AES IP Core. Several authors (see the references in (3)) have published papers detailing the implementation of the Advanced Encryption Standard (AES) on FPGA chips; however, the design goals of this AES core are somewhat different from previous work. Rather than emphasizing performance our design emphasizes

Valeri F. Tomashau; Tom Kean

2004-01-01

322

Trial of antiepilepsirine (AES) in children with epilepsy  

Microsoft Academic Search

Antieplepsirine (AES) is a new antiepileptic drug (AED) which was originally extracted from a Chinese folk remedy, and is now chemically characterized and synthesized. Its chemical structure is different from those of other available AEDs. Animal experiments involving AES demonstrated significant antiepileptic activity. Only a few clinical studies of AES with open trial have been resorted, none of which were

Li Wang; Da-yao Zhao; Zong-hao Zhang; Chi-hua Zuo; Yuan Zhang; Yin Quan Pei; Yia Qing Lo

1999-01-01

323

15 CFR Appendix D to Part 30 - AES Filing Citation, Exemption and Exclusion Legends  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false AES Filing Citation, Exemption and Exclusion Legends ...Appendix D to Part 30AES Filing Citation, Exemption and Exclusion Legends I. USML Proof of Filing Citation AES ITN Example: AES...

2013-01-01

324

15 CFR Appendix D to Part 30 - AES Filing Citation, Exemption and Exclusion Legends  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false AES Filing Citation, Exemption and Exclusion Legends ...Appendix D to Part 30AES Filing Citation, Exemption and Exclusion Legends I. USML Proof of Filing Citation AES ITN Example: AES...

2012-01-01

325

Computer Aided Systems Theory and Knowledge-Based System Design and Simulation; Directions to Explore  

Microsoft Academic Search

This paper examines a possible merger of methods and techniques of Computer Aided Systems Theory (CAST) and Knowledge-Based System Design and Simulation Methodology. The basic tenets of both methodologies and the state of their implementation in computer-aided environments are discussed. The central focus of the paper is the application of CAST techniques to support the design model construction and development

Jerzy W. Rozenblit; Herbert Praehofer

1989-01-01

326

New concepts in exploring subsalt Paleozoic hydrocarbon systems in mature and near producing areas of Morocco  

SciTech Connect

The subsalt Paleozoic hydrocarbon systems are one of the areally largest and paradoxally the least drilled in Morocco. Although, worldwide, these systems contain the largest potential gas reserves and contain one of the largest emerging oil plays and better still the few wells drilled to test the system in Essaouira Basin are producing commercial wet gas, these systems have never been tested in the Interatlasic and Prerif Basins. Impediments to exploration in these areas focused on the inability to map beneath the [open quotes]geophysical basement[close quotes], to seismically image sub-salt, pre-Jurassic block faulted structures and the perceived lack of adequate source rock. Recent integrated study combining newly acquired deep targeted seismic, gravity, magnetic, geochemical data and basin modelling techniques, has permitted to decipher the pre-salt structures, interpret basin evolution and assess source rock potential. The sub-salt Paleozoic hydrocarbon system evolved in basically five stages: (1) simultaneous sediment accumulation and structural formation during the Paleozoic; (2) major tectonism and erosion in Late Paleozoic (Hercynian); (3) Triassic-Lower Jurassic deposition of a regional seal (salt and evaporate); (4) Mesozoic charging primarily from Silurian to Carboniferous sources; and (5) re-initiation of generation from Silurian source in uplifted blocks following atlasic (Neogene) compression. Large structures and prospective stratigraphic features exhibiting many similarities to the prolific Triassic objectives of neighboring Algeria are now defined and await to be drilled. Furthermore, the Maghreb-Europe gas pipeline will shortly cross both the Interatlasic and the Prerif areas providing additional positive attribute that makes these exploration areas more attractive.

Jabour, H.; Deminati, A.; Hcaine, M.; El Alji, M. (ONAREP, Rabat (Morocco))

1996-01-01

327

Preliminary Results from NEOWISE: An Enhancement to the Wide-field Infrared Survey Explorer for Solar System Science  

Microsoft Academic Search

The Wide-field Infrared Survey Explorer (WISE) has surveyed the entire sky at four infrared wavelengths with greatly improved sensitivity and spatial resolution compared to its predecessors, the Infrared Astronomical Satellite and the Cosmic Background Explorer. NASA's Planetary Science Division has funded an enhancement to the WISE data processing system called \\

A. Mainzer; J. Bauer; T. Grav; J. Masiero; R. M. Cutri; J. Dailey; P. Eisenhardt; R. S. McMillan; E. Wright; R. Walker; R. Jedicke; T. Spahr; D. Tholen; R. Alles; R. Beck; H. Brandenburg; T. Conrow; T. Evans; J. Fowler; T. Jarrett; K. Marsh; F. Masci; H. McCallon; S. Wheelock; M. Wittman; P. Wyatt; E. DeBaun; G. Elliott; D. Elsbury; T. Gautier IV; S. Gomillion; D. Leisawitz; C. Maleszewski; M. Micheli; A. Wilkins

2011-01-01

328

Artificial epi-Retinal Prosthesis (AeRP)  

NASA Astrophysics Data System (ADS)

There are several research projects going on around the world, which are attempting to develop a prosthetic device to restore sight to the blind. This paper describes the efforts of Second Sight of New York, Inc. The device being developed is called an Artificial epi-Retinal Prosthesis (AeRP), which is basically a small optical computer that fits into the intraocular space of the eye. The AeRP is designed to draw light into the device by specially designed fibre optics. The light is digitized by the fibre optic system and then directed to individual photodiode cells making up concentric cylinders thus providing several hundred photodiode cells in the device. The produced electrical stimulation from each cell is then delivered to the retinal ganglion cells by a specially designed delivery system utilizing electrically conducting polymer strands (ECP), which sit on an umbrella at the back of the device. The retinal ganglion cells receive the electrical stimulation, which would then be transmitted through the visual system of the brain. There are several innovations in this approach as compared to the other projects. They include, first the design, which will allow for a high number of PC to produce electrical stimulation that will stimulate multiple RGC per PC; the use of the ECP strands has not been used in such an approach before this. Tests have revealed that nerve cells have a good affinity for the material of the ECP. The use of the ECP as well as the fact that the AeRP is completely photovoltaic, with no external power sources, implies that there will not be high heat build-up in the back of the eye, which might damage RGC. A smaller version of the AeRP called the Mini epi-Retinal Prosthesis (MeRP) is the subject of a complimentary paper. It is being built now and will be tested in cell culture studies to determine the efficacy of the design and materials. No actual implants have been performed yet.

Doorish, John F.

2006-09-01

329

Applying Health Management Technology to the NASA Exploration System-of-Systems  

Microsoft Academic Search

Human-rated space flight systems are characterized by intense concerns for flight crew safety and for high costs of operations and development. Non-human-rated space flight systems associated with cargo or scientific\\/robotic payloads are only slightly different. They are characterized by concerns for reliability and performance as well as for high costs of operations and development. In the past, across the aerospace

Edward N Brown; Bala Chidambaram; Gordon B Aaseng; Carlos Garcia-Galan

2005-01-01

330

Drills, Scoops, Grinders, Brushing Tools, Crushers, and Sample Manipulation Systems Enabling Mars Exploration.  

NASA Astrophysics Data System (ADS)

In the last decade, Honeybee Robotics Spacecraft Mechanism Corporation has developed over a dozen planetary drill systems, scoops, grinders, crushers and sample manipulation systems. These systems were built to meet specific requirements such as reaching certain depths, exhibiting certain levels of autonomy, acquiring samples of certain sizes and integrity (e.g. core vs. powder). They were built to operate at restricted power values. Most of the systems were tested either in the planetary analogs such as the Arctic, and/or laboratory, and/or environmental chambers and for this reason are at different Technology Readiness Levels. The presentation will cover a range of various drill systems as well as flight hardware developed by Honeybee Robotics. The existing flight hardware includes Rock Abrasion Tool on Mars Exploration Rovers currently operating on the surface of Mars, a Phoenix Scoop with a small drill called the RASP (the Phoenix lander is scheduled to land on Mars on May 25th), and the Sample Manipulation System that will be launched to Mars onboard of Mars Science Laboratory Rover in 2009. The presentation will focus on science enabled but these different instruments as well as challengers in developing a flight-ready hardware and operating the hardware from Earth.

Zacny, Kris; Davis, Kiel; Paulsen, Gale; Gorevan, Steven; Mumm, Erik

331

Exploring the History of Time in an Integrated System: the Ramifications for Water  

NASA Astrophysics Data System (ADS)

Characteristic time scales are useful and simple descriptors of geophysical and socio-economic system dynamics. Focusing on the integrative nature of the hydrologic cycle, new insights into system couplings can be gained by compiling characteristic time scales of important processes driving these systems. There are many examples of changing characteristic time scales. Human life expectancy has increased over the recent history of medical advancement. The transport time of goods has decreased with the progression from horse to rail to car to plane. The transport time of information changed with the progression from letter to telegraph to telephone to networked computing. Soil residence time (pedogenesis to estuary deposition) has been influenced by changing agricultural technology, urbanization, and forest practices. Surface water residence times have varied as beaver dams have disappeared and been replaced with modern reservoirs, flood control works, and channelization. These dynamics raise the question of how these types of time scales interact with each other to form integrated Earth system dynamics? Here we explore the coupling of geophysical and socio-economic systems in the northeast United States over the 1600 to 2010 period by examining characteristic time scales. This visualization of many time scales serves as an exploratory analysis, producing new hypotheses about how the integrated system dynamics have evolved over the last 400 years. Specifically, exponential population growth and the evolving strategies to maintain that population appears as fundamental to many of the time scales.

Green, M. B.; Adams, L. E.; Allen, T. L.; Arrigo, J. S.; Bain, D. J.; Bray, E. N.; Duncan, J. M.; Hermans, C. M.; Pastore, C.; Schlosser, C. A.; Vorosmarty, C. J.; Witherell, B. B.; Wollheim, W. M.; Wreschnig, A. J.

2009-12-01

332

Designing an intelligent health monitoring system and exploring user acceptance for the elderly.  

PubMed

Recently, many healthcare or health monitoring systems are proposed to improve life quality of the elderly in the aging process. The elderly are generally with poor health and low information literacy. Low information literacy might be an obstacle of using such systems. This research considered the characteristics and the needs of the elderly and developed an intelligent health monitoring system for the elderly with low information literacy living in the nursing home. The system is intelligent since it can monitor the health status of the elderly based on clinical and medical knowledge, provide an easy-to-understand and easy-to-use user interface for the elderly, and automatically send important or emergency feedback to caregivers. Finally, we explored the user acceptance for the elderly using our proposed system based on the unified theory of acceptance and user of technology model. The experimental results indicate the developed system is highly accepted by the elderly in terms of performance expectation, endeavor expectation, social influence, and facilitating condition. PMID:24037138

Tseng, Kevin C; Hsu, Chien-Lung; Chuang, Yu-Hao

2013-09-15

333

Operation database petroleum GIS results: Evaluation and application of geographic information systems to exploration and production  

SciTech Connect

FACT: Maps are the principle graphic tool used in exploration and production. FACT: The geographic information systems (GTS) industry exceeds $250 million annually providing powerful mapping tools to a variety of disciplines. FACT: Geographic information systems are infrequently used in exploration and production which represents less than 2% of the total GIS sphere. Therefore, Operation Database Petroleum GIS, sponsored by AAPG's Geobyte and the National Computer Graphics Association, was conceived as an information exchange between the petroleum industry and GIS vendors to address this disparity. The objective of the database was to communicate petroleum industry requirements to GIS vendors and to demonstrate the potential of GIS to the petroleum industry. Requirements, in the form of data and problems, were developed by an industry group representing major and independent oil companies. The problems included base map, well, seismic, lease, transportation, topographic, three-dimensional, and remote sensing exercises. Data included scout well data, directional surveys, production histories, seismic shot-point locations and interpretive times, geologic interpretations (tops and structure and isopach maps), leases, topography, well logs, remote sensing images, gravity contours, and geographic reference information. Over 120 GIS vendors were offered a chance to participate, and nearly 20 engaged in the exercises. This talk will focus on the process, results, and conclusions of Operation Database Petroleum GIS.

Fried, C.C. (Amoco Production Co., Denver, CO (USA)); Leonard, J.E. (Platte River Associates, Denver, CO (USA))

1990-05-01

334

Alteration minerals in impact-generated hydrothermal systems Exploring host rock variability  

NASA Astrophysics Data System (ADS)

Impact-generated hydrothermal systems have been previously linked to the alteration of Mars' crust and the production of secondary mineral assemblages seen from orbit. The sensitivity of the resultant assemblages has not yet been evaluated as a function of precursor primary rock compositions. In this work, we use thermochemical modeling to explore the variety of minerals that could be produced by altering several known lithologies based on martian meteorite compositions. For a basaltic host rock lithology (Dhofar 378, Humphrey) the main alteration phases are feldspar, zeolite, pyroxene, chlorite, clay (nontronite, kaolinite), and hematite; for a lherzolithic host rock lithology (LEW 88516) the main alteration phases are amphibole, serpentine, chlorite, clay (nontronite, kaolinite), and hematite; and for an ultramafic host rock lithology (Chassigny) the main minerals are secondary olivine, serpentine, magnetite, quartz, and hematite. These assemblages and proportions of phases in each of those cases depend on W/R and temperature. Integrating geologic, hydrologic and alteration mineral evidence, we have developed a model to illustrate the distribution of alteration assemblages that occur in different levels of an impact structure. At the surface, hot, hydrous alteration affects the ejecta and melt sheet producing clay and chlorite. Deeper in the subsurface and depending on the permeability of the rock, a variety of minerals - smectite, chlorite, serpentine, amphiboles and hematite - are produced in a circulating hydrothermal system. These modeled mineral distributions should assist with interpretation of orbital observations and help guide surface exploration by rovers and sample return assets.

Schwenzer, Susanne P.; Kring, David A.

2013-09-01

335

Exploring the Role of Method Rationale in the Context of Teaching Information Systems Development Methods  

NASA Astrophysics Data System (ADS)

Research has shown that traditional education in systems development has its limitations. This chapter draws on recent research on a component-based view of systems development methods. The aim is to explore the impact of applying a method rationale perspective during method teaching with regards to student's abilities to reason about the suitability of a particular method to various development settings. A qualitative research approach was adopted, which used two different approaches to teaching a particular method to two groups of students. The students' ability to reason about the method in modelling seminars and follow-up interviews was analysed. The results indicate that explicating method rationale in teaching methods may have a positive impact on students' ability to reason about methods and method tailoring.

Wistrand, Kai; Karlsson, Fredrik; gerfalk, Pr J.

336

Exploring Process Groups for Reliability, Availability and Serviceability of Terascale Computing Systems  

SciTech Connect

This paper presents various aspects of reliability, availability and serviceability (RAS) systems as they relate to group communication service, including reliable and total order multicast/broadcast, virtual synchrony, and failure detection. While the issue of availability, particularly high availability using replication-based architectures has recently received upsurge research interests, much still have to be done in understanding the basic underlying concepts for achieving RAS systems, especially in high-end and high performance computing (HPC) communities. Various attributes of group communication service and the prototype of symmetric active replication following ideas utilized in the Newtop protocol will be discussed. We explore the application of group communication service for RAS HPC, laying the groundwork for its integrated model.

Okunbor, Daniel Irowa [ORNL; Engelmann, Christian [ORNL; Scott, Steven L [ORNL

2006-06-01

337

Exploring corner transfer matrices and corner tensors for the classical simulation of quantum lattice systems  

NASA Astrophysics Data System (ADS)

In this paper we explore the practical use of the corner transfer matrix and its higher-dimensional generalization, the corner tensor, to develop tensor network algorithms for the classical simulation of quantum lattice systems of infinite size. This exploration is done mainly in one and two spatial dimensions (1D and 2D). We describe a number of numerical algorithms based on corner matrices and tensors to approximate different ground-state properties of these systems. The proposed methods also make use of matrix product operators and projected entangled pair operators and naturally preserve spatial symmetries of the system such as translation invariance. In order to assess the validity of our algorithms, we provide preliminary benchmarking calculations for the spin-1/2 quantum Ising model in a transverse field in both 1D and 2D. Our methods are a plausible alternative to other well-established tensor network approaches such as iDMRG and iTEBD in 1D, and iPEPS and TERG in 2D. The computational complexity of the proposed algorithms is also considered and, in 2D, important differences are found depending on the chosen simulation scheme. We also discuss further possibilities, such as 3D quantum lattice systems, periodic boundary conditions, and real-time evolution. This discussion leads us to reinterpret the standard iTEBD and iPEPS algorithms in terms of corner transfer matrices and corner tensors. Our paper also offers a perspective on many properties of the corner transfer matrix and its higher-dimensional generalizations in the light of novel tensor network methods.

Ors, Romn

2012-05-01

338

Crustal stress, seismicity, acoustic emission (AE), and tectonics: the Kefallin;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 Kefallina (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, Kefallina 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

339

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

NASA Astrophysics Data System (ADS)

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

Lee, Wooju; Cho, Kyongkuk; Yoon, Dongweon

2010-03-01

340

Coordinated Multiwavelength Observations of AE Aqr  

NASA Astrophysics Data System (ADS)

We propose to conduct an ambitious campaign of coordinated multiwavelength observations of the former supersoft X-ray binary and current magnetic propeller AE Aqr. Recent XMM observations have thrown into doubt the source of the X-ray emission and the heating of the optical and UV emission line regions. We propose to observe AE Aqr for 2 binary orbits with the Chandra HETG to measure the radial velocity variations of the X-ray emission lines and constrain the plasma density. We also propose to obtain 6 orbits of HST high-resolution time-tagged UV spectroscopy and 12 hrs of VLA time, to which we will add mm through gamma-ray data. These data will provide the most complete picture of the locations, mass motions, energetics, and interrelationships of the various emission regions.

Mauche, Christopher

2004-09-01

341

Coordinated Multiwavelength Obsevations of AE Aqr  

NASA Astrophysics Data System (ADS)

We propose to conduct an ambitious campaign of coordinated multiwavelength observations of the former supersoft X-ray binary and current magnetic propeller AE Aqr. Recent XMM observations have thrown into doubt the source of the X-ray emission and the heating of the optical and UV emission line regions. We propose to observe AE Aqr for 2 binary orbits with the Chandra HETG to measure the radial velocity variations of the X-ray emission lines and constrain the plasma density. We also propose to obtain 6 orbits of HST high-resolution time-tagged UV spectroscopy and 12 hrs of VLA time, to which we will add mm through gamma-ray data. These data will provide the most complete picture of the locations, mass motions, energetics, and interrelationships of the various emission regions.

Mauche, Christopher

2004-07-01

342

NEXT Ion Propulsion System Configurations and Performance for Saturn System Exploration.  

National Technical Information Service (NTIS)

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, ...

S. W. Benson J. P. Riehl S. R. Oleson

2007-01-01

343

a Carbon Dioxide Collection and Pressure Generation Breadboard System for Mars Exploration  

NASA Astrophysics Data System (ADS)

In the framework of development programs for future European Space Agency (ESA) missions aimed at Mars exploration, a breadboard propulsion system has been developed at Commissariat l'Energie Atomique (CEA-INAC/SBT). The objective is to design a system that can produce a thrust sufficient to move the whole device on the planet surface. In order to reduce the cost and the mass launched, the system uses the particular properties of the planet atmosphere which contains 98% of carbon dioxide (CO2). First the CO2 atmospheric gas is collected in a very high density storage tank using a cryopumping process (condensation of gas at around 140 K). Then an applied heat load allows generation of a continuous high pressure and high flow rate CO2 discharge, which will be used to feed the future nozzles of the system. The present system is designed to study the cryopumping process in a 0.6 liter collection tank and the discharge through an exhaust line. The design principles are presented, and the breadboard is described. Some preliminary results are then presented and discussed. As an example, the presented design allows the collection of 220 g of solid CO2 during a one shot 3 hr cryopumping process. This amount has been increased to 440 g by performing several thermal cycles. The discharge is achieved with 10 g/s maximum flow rate at 5 MPa maximum.

Gully, Ph.; Ercolani, E.; Guillemet, L.; Sirbi, A.; Linder, M.

2010-04-01

344

The Hardware Challenges for the Mars Exploration Rover Heat Rejection System  

NASA Astrophysics Data System (ADS)

The primary objective of the Mars Exploration Rover (MER) 2003 Project focused on the search for evidence of water on Mars. The launch of two identical flight systems occurred in June and July of 2003. The roving science vehicles are expected to land on the Martian surface in early and late January of 2004, respectively. The flight system design inherited many successfully features and approaches from the Mars Pathfinder Mission. This included the use of a mechanically-pumped fluid loop, known as the Heat Rejection System (HRS), to transport heat from the Rover to radiators on the Cruise Stage during the quiescent trek to Mars. While the heritage of the HRS was evident, application of this system for MER presented unique and difficult challenges with respect to hardware implementation. We will discuss these hardware challenges in each HRS hardware element: the integrated pump assembly, cruise stage HRS, lander HRS, and Rover HRS. These challenges span the entire development cycle including fabrication, assembly, and test. We will conclude by citing the usefulness of this system during launch operations, where in particular, the flight hardware inside the Rover was thermally conditioned by the HRS since there was no other effective means of maintaining its temperature.

Tsuyuki, Glenn; Ganapathi, Gani; Bame, David; Patzold, Jack; Fisher, Richard; Theriault, Laurent

2004-02-01

345

An exploration framework to identify and track movement of cloud systems.  

PubMed

We describe a framework to explore and visualize the movement of cloud systems. Using techniques from computational topology and computer vision, our framework allows the user to study this movement at various scales in space and time. Such movements could have large temporal and spatial scales such as the Madden Julian Oscillation (MJO), which has a spatial scale ranging from 1000 km to 10000 km and time of oscillation of around 40 days. Embedded within these larger scale oscillations are a hierarchy of cloud clusters which could have smaller spatial and temporal scales such as the Nakazawa cloud clusters. These smaller cloud clusters, while being part of the equatorial MJO, sometimes move at speeds different from the larger scale and in a direction opposite to that of the MJO envelope. Hitherto, one could only speculate about such movements by selectively analysing data and a priori knowledge of such systems. Our framework automatically delineates such cloud clusters and does not depend on the prior experience of the user to define cloud clusters. Analysis using our framework also shows that most tropical systems such as cyclones also contain multi-scale interactions between clouds and cloud systems. We show the effectiveness of our framework to track organized cloud system during one such rainfall event which happened at Mumbai, India in July 2005 and for cyclone Aila which occurred in Bay of Bengal during May 2009. PMID:24051857

Doraiswamy, Harish; Natarajan, Vijay; Nanjundiah, Ravi S

2013-12-01

346

Low Voltage Fault Attacks to AES  

Microsoft Academic Search

This paper presents a new fault based attack on the Advanced Encryption Standard (AES) with any key length, together with its practical validation through the use of low voltage induced faults. The CPU running the attacked algorithm is the ARM926EJ-S: a 32-bit processor widely deployed in computer peripherals, telecommunication appliances and low power portable devices. We prove the practical feasibility

Alessandro Barenghi; Guido M. Bertoni; Luca Breveglieri; Mauro Pellicioli; Gerardo Pelosi

2010-01-01

347

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

348

The 2013 flare of ASASSN-13ae  

NASA Astrophysics Data System (ADS)

We followed in the V band the flare of ASASSN-13ae in 2013. The light curve shape is in agreement with that of a previous burst in 2007, and suggestive of a CV of WZ Sge type with recurrence of 5.9 years. A search for short-term periodicity over 3 hours on MJD 56421 gave no results at 0.03 mag level.

Nesci, R.; Caravano, A.; Falasca, V.; Villani, L.

2013-06-01

349

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

350

AC/DC Power Systems with Applications for future Lunar/Mars base and Crew Exploration Vehicle.  

National Technical Information Service (NTIS)

ABSTRACT The Power Systems branch at JSC faces a number of complex issues as it readies itself for the President's initiative on future space exploration beyond low earth orbit. Some of these preliminary issues - those dealing with electric power generati...

B. H. Chowdhury

2005-01-01

351

Exploration of the Solar System: Achievements and Future Plans in NASA's (National Aeronautics and Space Administration) Programme.  

National Technical Information Service (NTIS)

The Voyager 2 encounter with Uranus, ground-based and spacecraft observations of Comet Halley, and other NASA solar system exploration is reviewed. The Challenger tragedy significantly delayed the next NASA planetary mission, Galileo, as well as the Ulyss...

W. E. Brunk

1986-01-01

352

A dynamic isotope power system for Space Exploration Initiative surface transport systems  

Microsoft Academic Search

The Dynamic Isotope Power System (DIPS) Demonstration Program, sponsored by the U.S. Department of Energy with support funding from NASA, is currently focused on the development of a standardized 2.5-kWe portable generator for multiple applications on the lunar or Martian surface. A variety of remote and mobile potential applications have been identified by NASA, including surface rovers for both short-

M. E. Hunt; R. B. Harty; R. Cataldo

1992-01-01

353

Hierarchy and nonstationarity in climate systems: Exploring the prediction of complex systems  

Microsoft Academic Search

The prediction theories for complex systems with a hierarchical structure and their applications to the climate process are\\u000a a significant and forward-looking field of research. However, up to the present, they are yet not known and understood very\\u000a well. This paper presents a preliminary theoretical frame for them. As a normal example, the basic behaviors and the dynamic\\u000a structure of

Peicai Yang; Jianchun Bian; Geli Wang; Xiuji Zhou

2003-01-01

354

Case-History Explorations of Scientifically Significant Earth-System Events  

NASA Astrophysics Data System (ADS)

We are developing case histories of recent and ancient natural disasters to provide students a means of learning fundamental earth system science and applying their new understanding to mitigating disasters in the future. We distinguish case histories from case studies in that they investigate real problems that are likely to recur, as opposed to hypothetical but realistic problem scenarios. Students explore the scientific and societal conditions that caused or fueled a disaster; investigate whether the outcome might have been different under different conditions; explore how the disaster has shaped our scientific and societal understanding of such events; and propose appropriate responses and preparation measures for future events. Each case history allows for multiple directions of investigation by individuals or teams. The case histories incorporate actual datasets used by scientists to analyze the event, in addition to analysis tools such as GIS, Excel, and Google Earth. These classroom resources are appropriate for undergraduate earth system majors from first year to third year. We have completed and are field testing case histories for the 1994 M6.7 Northridge earthquake and the Super Tornado Outbreak of 1974, as well as other notable tornado outbreaks. Additionally, we are developing case histories for the 1700 Cascadia mega-tsunami and the 2005 Hurricane Katrina. Research studies of each of these events have resulted in significant changes to our understanding of the earth processes that caused them, and have spawned renewed interest in hazard mitigation. Each case history also incorporates the human element, presented from both a scientific and eyewitness perspective. Field testing includes evaluation of scientific accuracy, usability and pedagogical effectiveness, as described in the DLESE peer-review-system criteria (www.dlese-project.org/review_criteria.html) by field testers and external technical experts.

Hall, M. K.; Walker, C. S.; Mayhew, M. A.

2007-12-01

355

A water system model for exploring electric energy alternatives in southeastern US basins  

NASA Astrophysics Data System (ADS)

Electric power generation often involves the use of water for power plant cooling and steam generation, which typically involves the release of cooling water to nearby rivers and lakes. The resulting thermal pollution may negatively impact the ecosystems of these water bodies. Water resource systems models enable the examination of the implications of alternative electric generation on regional water resources. This letter documents the development, calibration, and validation of a climate-driven water resource systems model of the Apalachicola-Chattahoochee-Flint, the Alabama-Coosa-Tallapoosa, and the Tombigbee River basins in the states of Georgia, Alabama, and Florida, in the southeastern US. The model represents different water users, including power plants, agricultural water users, and municipal users. The model takes into account local population, per-capita use estimates, and changes in population growth. The water resources planning model was calibrated and validated against the observed, managed flows through the river systems of the three basins. Flow calibration was performed on land cover, water capacity, and hydraulic conductivity of soil horizons; river water temperature calibration was performed on channel width and slope properties. Goodness-of-fit statistics indicate that under 1980-2010 levels of water use, the model robustly represents major features of monthly average streamflow and water temperatures. The application of this integrated electricity generation-water resources planning model can be used to explore alternative electric generation and water implications. The implementation of this model is explored in the companion paper of this focus issue (Yates et al 2013 Environ. Res. Lett. 8 035042).

Flores-Lpez, F.; Yates, D.

2013-09-01

356

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

357

The PEGASUS Drive: A nuclear electric propulsion system for the space exploration initiative  

SciTech Connect

The advantages of using electric propulsion for propulsion are well-known in the aerospace community. The high specific impulse, lower propellant requirements, and lower system mass make it a very attractive propulsion option for the Space Exploration Initiative (SEI), especially for the transport of cargo. One such propulsion system is the PEGASUS Drive (Coomes et al. 1987). In its original configuration, the PEGASUS Drive consisted of a 10-MWe power source coupled to a 6-MW magnetoplasmadynamic (MPD) thruster system. The PEGASUS Drive propelled a manned vehicle to Mars and back in 601 days. By removing the crew and their associated support systems from the spacecraft and by incorporating technology advances in reactor design and heat rejection systems, a second generation PEGASUS Drive can be developed with an alpha less than two. Utilizing this propulsion system, a 400-MT cargo vehicle, assembled and loaded in low Earth orbit (LEO), could deliver 262 MT of supplies and hardware to Mars 282 days after escaping Earth orbit. Upon arrival at Mars the transport vehicle would place its cargo in the desired parking orbit around Mars and then proceed to synchronous orbit above the desired landing sight. Using a laser transmitter, PEGASUS would provide 2-MWe on the surface to operate automated systems deployed earlier and then provide surface power to support crew activities after their arrival. The additional supplies and hardware, coupled with the availability of megawatt levels of electric power on the Mars surface, would greatly enhance and even expand the mission options being considered under SEI. 9 refs., 1 fig., 1 tab.

Coomes, E.P.; Dagle, J.E.

1990-10-01

358

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

NASA Astrophysics Data System (ADS)

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

Esper, Jaime

2005-02-01

359

Development of HTS-SQUID magnetometer system with high slew rate for exploration of mineral resources  

NASA Astrophysics Data System (ADS)

For the transient electromagnetic (TEM) method using a high-temperature superconducting interference device (HTS-SQUID), we have developed a magnetometer system with a wide dynamic range, a high slew rate, and superior transportability. To achieve high tolerance to a higher excitation magnetic field, we utilized a SQUID magnetometer containing ramp-edge junctions with La0.1Er0.95Ba1.95Cu3Oy and SmBa2Cu3Oy electrode layers, which was fabricated by using an HTS multi-layer fabrication technique. To operate the magnetometer stably in a rapidly changing magnetic field, we chose the proper materials for the RF shield of liquid nitrogen (LN2) glass Dewar and cables. The white noise level and the slew rate of the system were measured to be 30 fT Hz-1/2 and 10.5 mT s-1, respectively. The resultant signal-to-noise ratio was higher than that of the previous system and improved the exploration depth, which was successfully demonstrated in field tests. The weight of the Dewar, which retains the LN2 for 17 h, is 2.5 kg. The total weight of our system including the LN2 Dewar, a probe with a flux-locked loop (FLL) circuit, a battery, a receiver, and a 30 m-long cable between the FLL and the receiver is as low as 25.6 kg.

Hato, T.; Tsukamoto, A.; Adachi, S.; Oshikubo, Y.; Watanabe, H.; Ishikawa, H.; Sugisaki, M.; Arai, E.; Tanabe, K.

2013-11-01

360

JUpiter ICy moons Explorer (JUICE): An ESA L-Class Mission Candidate to the Jupiter System  

NASA Astrophysics Data System (ADS)

JUICE is the next step for an in-depth exploration of the geophysical and environmental characteristics of Ganymede and exploration of Callisto and Europa, and will provide an in-depth understanding of Jupiters atmosphere and magnetosphere.

Dougherty, M.; 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.

2012-03-01

361

Exploring the parallel development of microbial systems in neonates with cystic fibrosis.  

PubMed

Recent studies have greatly extended our understanding of the microbiota present in and on the human body. Here, advanced sequencing strategies have provided unprecedented analytical power. The important implications that the emerging data have for human health emphasize the need to intensify research in this area (D. A. Relman, Nature 486:194-195, 2012). It is already clear from these studies that the microbiotas characterized in different body locations of healthy individuals are both complex and diverse (The Human Microbiome Project Consortium, Nature 486:215-221). These studies also provide a point of contrast for investigations that aim to characterize the microbiota present in disease conditions. In this regard, Madan et al. (mBio 3(4):e00251-12, 2012) monitored the development over time of microbiota in the oropharynges and feces of neonates with cystic fibrosis and explored the potential for interactions between these complex microbial systems. PMID:23131830

Rogers, Geraint B; Bruce, Kenneth D

2012-11-06

362

Marco Polo: International Small Solar System Body Exploration Mission in 2010's  

NASA Astrophysics Data System (ADS)

Since 2000, Japanese scientists and engineers have investigated new generation primitive body missions in the post-Hayabusa era in 2010's. Receiving the Minorbody Exploration Forum Final Report, ISAS established the nation-wide Small Body Exploration Working Group (SBE-WG) in 2004. After the successful exploration of the S-type NEO Itokawa by Hayabusa in 2005, the Hayabusa-2 concept emerged for a C-type asteroid sample return by the original Hayabusa spacecraft system with minor improvements and modifications. In parallel to that effort, the SBE-WG continued to develop the post-Hayabusa mission concept as "Hayabusa Mk-II," a fully model-changed, advanced spacecraft with the sample return capability from the most primitive bodies of the solar system. It is this Hayabusa Mk-II that has became the foundation of the International small body exploration concept "Marco Polo" since 2006. Jointly proposed to the first call of the ESA Cosmic Vision by scientists from Japan, Europe, and the U.S., the Marco Polo concept was selected as one of the M-class mission candidates for the assessment study phase in the fall of 2007. In 2008, the international joint study team has been created and its mission definitions, system requirements, and target selections are currently under the study. The top-level scientific themes are to decode the solar system formation and evolution in the astrobiology and astromineralogy contexts as one of the most important scientific challenges of 2010's. These themes are sub-divided into several objectives to be achieved by both instruments carried onboard the mother spacecraft (MSC), a large lander, or small hopping rovers and returned samples. The initial mission target candicdates include comet-asteroid transition (CAT) objects, D-type asteroids and C-type binary asteroids in near-Earth orbits. In the baseline scenario, a Soyuz launcher provided by ESA will launch the JAXA-made MSC with sampling and other in-situ science instruments provided by both JAXA and ESA, as well as the large European lander and a few small Japanese rovers as possible options, around 2018. In order to reach the CAT object Wilson-Harrington, MSC employs a cluster of improved ion engines inherited from the Hayabusa technology with the Earth gravity assist in the outbound interplanetary cruise. In 2022, the MSC will arrive the target and conduct global mapping and scientific investigation including sampling site selection in a few moths. Then the lander and rovers will be landed on the target surface to conduct cross-scale science being complementary to the MSC instruments and laboratory studies of returned samples. Toward the end of the stay, touch-and-go sequences for surface and possibly sub-surface sample collections will be attempted by taking advantages of operational experiences in the Hayabusa mission. In 2023, the MSC containing the collected samples inside the Earth return capsule will start the inbound cruise back to the Earth while the lander would continue to investigate in-situ the target surface. The sample delivery to the Earth and initial sample analyses, after the planetary quarantine procedure if necessary, will be expected in 2026.

Yano, Hajime

363

Exploring the elastic features of spherically shaped biological assemblies and soft matter systems  

NASA Astrophysics Data System (ADS)

Using a numerical simulation, we study the elastic features of biological assemblies (e.g. viruses and bacteria) and soft matter systems (e.g. colloidosomes and nanoparticle covered droplets) that possess a spherical shape in which the proteins (particles) on the colloidosomes or virus shells are mechanically linked to form a stress-bearing spherical structure that may dramatically enhance the surface rigidity. The dependence of the rigidity enhancement upon the density of the cross-linked proteins situated on the surface of the virus is explored. We determine the percolation threshold Pce by considering bond percolation on the spherical elastic networks involving nearest neighbor forces. The percolation threshold of such networks is very different from that of a two-dimensional triangular lattice due to the topological effect. We find that the threshold probability for the spherical elastic network is considerably smaller than for an unwrapped network, which reveals that the spherical topology induces more rigidity to the network.

Asfaw, Mesfin

2011-03-01

364

Exploring the Parallel Development of Microbial Systems in Neonates with Cystic Fibrosis  

PubMed Central

ABSTRACT Recent studies have greatly extended our understanding of the microbiota present in and on the human body. Here, advanced sequencing strategies have provided unprecedented analytical power. The important implications that the emerging data have for human health emphasize the need to intensify research in this area (D. A. Relman, Nature 486:194-195, 2012). It is already clear from these studies that the microbiotas characterized in different body locations of healthy individuals are both complex and diverse (The Human Microbiome Project Consortium, Nature 486:215-221). These studies also provide a point of contrast for investigations that aim to characterize the microbiota present in disease conditions. In this regard, Madan et al. (mBio 3(4):e00251-12, 2012) monitored the development over time of microbiota in the oropharynges and feces of neonates with cystic fibrosis and explored the potential for interactions between these complex microbial systems.

Rogers, Geraint B.; Bruce, Kenneth D.

2012-01-01

365

Detecting extended solar-system structures with COBE (Cosmic Background Explorer)  

SciTech Connect

The Cosmic Background Explorer (COBE) offers a new opportunity for the study of extended solar system structures discovered by the Infrared Astronomical Satellite (IRAS). It is expected that of these structures, Type II dust trails may be detected by the Diffuse Infrared Background Experiment (DIRBE) in which case there will be a final chance to discover their parent sources, which are as yet unknown, by immediate follow-up from groundbased imaging along the trail. Zodiacal dust bands will be easily detected at most wavelengths by DIRBE, allowing for additional analysis of their structure and geometry, as well as comparison at near-infrared wavelengths with the spectra of asteroid family members from which they are thought to derive. The other COBE experiments, as a consequence of their large beam sizes and long operating wavelengths, are not expected generally to detect these structures in the broad zodiacal emission.

Sykes, M.V.

1989-11-29

366

Petroleum systems of the Papuan Basin, Papua New Guinea, and their exploration potential  

SciTech Connect

The Papuan Basin of Papua New Guinea is a mature basin with a complex geologic history. The basin was initiated during Permo-Triassic rifting of the northern margin of Australia. Passive margin sedimentation occurred until the Oligocene to Recent when the basin was compressionally inverted, resulting in the formation of the present-day fold and thrust belt. Numerous hydrocarbon fields, some commercial, occur in traps along the front of the thrust belt. In mature complex basins such as this, it is critical to fully characterize existing petroleum systems as well as deliberately search for new systems. A recent systematic synthesis of the available geochemical data has defined three systems. Most important is the Jurassic system which is responsible for most of the oil and gas fields and all commercial production. Cretaceous and Tertiary systems, newly discovered in the basin, are based on detailed isotope and biomarker analysis of numerous oil seep. These additional petroleum systems open up new plays for exploration. To better define the pre-thrust basin geometry and help constrain the timing of hydrocarbon generation and migration, a series of palinspastically-stored cross-sections were constructed. Maturity modelling at different basin locations along these cross-sections evaluated the relative importance of two important species: (1) pre-thrust generation from local kitchens behind the present thrust belt, and (2) syn-thrust generation by loading of stacked thrust sheets within the fold belt. The relative importance of re-migration from pre-thrust traps vs direct charging into present day fold belt traps was evaluated using oil composition data.

Kaufman, R.L. [Chevron Overseas Petroleum, San Ramon, CA (United States); Phelps, J.C. [South Pacific Chevron, Brisbane (Australia)

1995-08-01

367

Factors affecting nurses' attitudes towards the screening and care of battered women in Dublin A&E departments: a literature review.  

PubMed

The concept of one human being inflicting unnecessary pain and suffering upon another, on a daily basis, is a disturbing and incredulous thought at the very least. This concept also known as domestic violence is all too real for the many victims presently suffering at the hands of their abusive partners. In Ireland, almost one in five women have experienced some form of domestic violence. This phenomenon can also be identified and further clarified as 'woman battering' Due to the confidential and accessible service offered to the client the Accident and Emergency department is a vital source of assistance to women who have been beaten by their partners. Battered women frequently present with injuries both visible and non-visible. More often than not however, many women are treated solely for their injuries and pass through the healthcare system unnoticed. Lydon (1996) estimates that of all presenting cases of domestic violence in the A&E department, only 5% are actually detected. Some literature estimates 3% detection rates (Thompson et al. 1998, Hadley, 1992). The following literature review explores the history behind the phenomenon of violence against women and its extent in Ireland. The literature affirming the important role of the nurse in A&E is reviewed and several themes are explored that affect nurses' attitudes in the screening and care of battered women. PMID:11760262

Corbally, M A

2001-01-01

368

Exploring discrimination in american health care system: perceptions/experiences of older Iranian immigrants.  

PubMed

The United States population is older and more diverse than ever before. Older Immigrant and minorities have been found to suffer from health care disparities. The National Institute of Health (2002) has identified discrimination as one of the factors that contributes to health disparities among immigrants and minority populations. The purpose of this qualitative phenomenological study was to explore older Iranian immigrants' perceptions/experiences of discrimination in their encounter with the American health care system. In depth interviews were conducted with 15 Iranians who had immigrated to the United States after the age of 50. The following major themes emerged from the study: 1) "American doctors don't discriminate", 2) class discrimination in American and Iranian health care system and 3) treating the illness and not the whole person. In general the participants reported that they did not perceive/experience discrimination in their encounter with the American health care system. In fact majority of the participants reported highly positive impressions of American health care providers. Some participants claimed that language barriers may have protected them from recognizing possible discriminations, while others reported that this absence of perceived discrimination may be a function of American provider's perception of a patient as an "illness" and not a whole person. PMID:22735985

Martin, Shadi Sahami

2012-09-01

369

Regulation of AE1 anion exchanger and H+ATPase in rat cortex by acute metabolic acidosis and alkalosis  

Microsoft Academic Search

Regulation of AE1 anion exchanger and H+-ATPase in rat cortex by acute metabolic acidosis and alkalosis. The cortical collecting duct (CCD) mediates net secretion or reabsorption of protons according to systemic acid\\/base status. Using indirect immunofluorescence, we examined the localization and abundance of the vacuolar H+-ATPase and the AE1 anion exchanger in intercalated cells (IC) of rat kidney connecting segment

Ivan Saboli?; Dennis Brown; Stephen L Gluck; Seth L Alper

1997-01-01

370

Uses of AES and RGA to study neutron-irradiation-enhanced segregation to internal surfaces  

SciTech Connect

The high flux of point defects to sinks during neutron irradiation can result in segregation of impurity or alloy additions to metals. Such segregants can be preexisting or produced by neutron-induced transmutations. This segregation is known to strongly influence swelling and mechanical properties. Over a period of years, facilities have been developed at ORNL incorporating AES and RGA to examine irradiated materials. Capabilities of this system include in situ tensile fracture at elevated temperatures under ultrahigh vacuum 10/sup -10/ torr and helium release monitoring. AES and normal incidence inert ion sputtering are exploited to examine segregation at the fracture surface and chemical gradients near the surface.

Gessel, G.R.; White, C.L.

1980-01-01

371

Jupiter Magnetospheric Orbiter and Trojan Asteroid Explorer in EJSM (Europa Jupiter System Mission)  

NASA Astrophysics Data System (ADS)

Europa Jupiter System Mission (EJSM) is an international mission to explore and Jupiter, its satellites and magnetospheric environment in 2020s. EJSM consists of (1) The Jupiter Europa Orbiter (JEO) by NASA, (2) the Jupiter Ganymede Orbiter (JGO) by ESA, and (3) the Jupiter Magnetospheric Orbiter (JMO) studied by JAXA (Japan Aerospace Exploration Agency). In February 2009, NASA and ESA decided to continue the study of EJSM as a candidate of the outer solar system mission. JMO will have magnetometers, low-energy plasma spectrometers, medium energy particle detectors, energetic particle detectors, electric field / plasma wave instruments, an ENA imager, an EUV spectrometer, and a dust detector. Collaborating with plasma instruments on board JEO and JGO, JMO will investigate the fast and huge rotating magnetosphere to clarify the energy procurement from Jovian rotation to the magnetosphere, to clarify the interaction between the solar wind the magnetosphere. Especially when JEO and JGO are orbiting around Europa and Ganymede, respectively, JMO will measure the outside condition in the Jovian magnetosphere. JMO will clarify the characteristics of the strongest accelerator in the solar system with the investigation of the role of Io as a source of heavy ions in the magnetosphere. JAXA started a study of a solar power sail for deep space explorations. Together with a solar sail (photon propulsion), it will have very efficient ion engines where electric power is produced solar panels within the sail. JAXA has already experienced ion engine in the successful Hayabusa mission, which was launched in 2003 and is still in operation in 2010. For the purpose of testing solar power sail technology, an engineering mission IKAROS (Interplanetary Kite-craft Accelerated by Radiation Of the Sun) will be launched in 2010 together with Venus Climate Orbiter PLANET-C. The shape of the IKAROS' membrane is square, with a diagonal distance of 20m. It is made of polyimide film only 0.0075mm thick. Currently we are studying a mission to Jupiter and one (or two) of Trojan asteroids using a large (100m-scale) solar power sail that can transfer large payload mass as far as Jupiter. Trojan asteroids are primitive bodies with information of the early solar system as well as raw solid materials of Jovian system. According to the mission plan, as the main spacecraft flies by Jupiter, it will deploy a JMO spinner around Jupiter. Proposed instruments on board Trojan spacecraft are cameras, IR spectrometers, XRS, a laser altimeter, and a surface vehicle (if rendezvous with the target is possible). An instrument for measuring cosmic background is also proposed. Currently JEO and JGO will be launched in 2020 and the Trojan spacecraft with JMO shall be launched at the same window. The mission (Trojan-JMO) will take 6 years to Jupiter and 5 years more to a Trojan asteroid around L4. The mission study team also includes J. Kawaguchi, Y. Kawakatsu, and M. Morimoto of JAXA.

Sasaki, Sho; Fujimoto, Masaki; Takashima, Takeshi; Yano, Hajime; Kasaba, Yasumasa; Takahashi, Yukihiro; Kimura, Jun; Tsuda, Yuichi; Funase, Ryu; Mori, Osamu

2010-05-01

372

A comprehensive study of proto-planetary disks around Herbig Ae stars using long-baseline infrared interferometry  

NASA Astrophysics Data System (ADS)

Planetary systems are born in circumstellar disks around young stellar objects (YSOs) and the disk is thought to play a major role in the evolution of planetary systems. A good understanding of disk structure and its time evolution is therefore essential in comprehending planet formation, planet migration and the diversity of planetary systems. In this thesis, I use high angular resolution observations and state-of-the-art radiative transfer modeling to probe circumstellar disk structure and validate current disk models. First, I discuss models and observations of the gas-dust transition region in YSOs. The dust component in circumstellar disks gets truncated at a finite radius from the central star, inside of which it is too hot for dust to survive. The truncated disk forms an "evaporation front" whose shape depends sensitively on dust properties. The possibility of using the front as a probe of the dust physics operating in circumstellar disks is explored. The Center for High Angular Resolution Astronomy (CHARA) near-infrared (near-IR) array is used to resolve out the evaporation front in the Herbig Ae stars MWC275 and AB Aur, and the presence of an additional near-IR opacity source within the "conventional" dust destruction radius is reported. Second, I describe comprehensive disk models that simultaneously explain the spectral energy distribution (from UV to milli-meter) and long-baseline interferometry (from near-IR to mm) of Herbig Ae stars. The models are constrained with a wide range of data drawn from the literature as well as new interferometric observations in the K-band with the CHARA array and in the mid-IR with the novel Keck Segment Tilting Experiment. I show that the mid-IR size of MWC275 relative to AB Aur is small, suggesting that dust grains in the outer disk of MWC275 are significantly more evolved/settled than the grains in the AB Aur disk. Using the Segment Tilting data, I also demonstrate that Herbig Ae/Be systems having a higher mid-IR surface brightness tend to have bluer mid-IR colors. I interpret this trend with simple geometric models for circumstellar disks. I conclude with a discussion on exciting prospects for measuring the gas-disk morphology on scales of fractions of an AU with the CHARA array, introducing a new powerful tool to understand the "star-disk connection".

Tannirkulam, Ajay-Kumar M.

373

Geochemistry and the Exploration of the Ngawha Geothermal System, New Zealand  

SciTech Connect

The Ngawha geothermal system is atypical of New Zealand geothermal systems, being located outside the Taupo Volcanic Zone, and contained in tight sedimentary structures. Early geochemical surveys of surface discharges indicated a high gas, high borate fluid, discharging in small quantities, to the surface. An initial well (drilled in the early 1960s, to 500m) produced a vary gassy fluid before calciting. Deeper wells drilled and discharged in the early 1980s produced large flows of high gas fluid (up to 3wt%), at enthalpies around 1000 kj/kg. These low energy contents coupled with a low water to rock ratio, a very fractured structure, and consequent expected changes in the production fluid following exploitation, let do large scale exploitation plans being scrapped in 1982. The close attention to geochemical studies before and during the drilling operations enabled predictions of fluid type, physical conditions at depth, fluid disposal problems, and hydrologic reservoir models that have proved to be correct. The project served to indicate the value of comprehensive exploration strategies which precede the drilling phase, and the further value of, in particular, geochemical studies as an integral part of well testing procedures, for the updating of reservoir models. The close and open cooperation amongst the scientist and engineers involved was also of great value. 2 tabs., 4 figs., 15 refs.

Sheppard, D.S.

1987-01-20

374

An alternative approach to solar system exploration providing safety of human mission to Mars.  

PubMed

For systematic human Mars exploration, meeting crew safety requirements, it seems perspective to assemble into a spacecraft: an electrical rocket, a well-shielded long-term life support system, and a manipulator-robots operating in combined "presence effect" and "master-slave" mode. The electrical spacecraft would carry humans to the orbit of Mars, providing short distance (and low signal time delay) between operator and robot-manipulators, which are landed on the surface of the planet. Long-term hybrid biological and physical/chemical LSS could provide environment supporting human health and well being. Robot-manipulators operating in "presence effect" and "master-slave" mode exclude necessity of human landing on Martian surface decreasing the level of risk for crew. Since crewmen would not have direct contact with the Martian environment then the problem of mutual biological protection is essentially reduced. Lightweight robot-manipulators, without heavy life support systems and without the necessity of returning to the mother vessel, could be sent as scouts to different places on the planet surface, scanning the most interesting for exobiological research site. Some approximate estimations of electric spacecraft, long-term hybrid LSS, radiation protection and mission parameters are conducted and discussed. PMID:12577896

Gitelson, J I; Bartsev, S I; Mezhevikin, V V; Okhonin, V A

2003-01-01

375

Mutnovsky Volcano: Exploring the feedback loop between arc volcanism and continental hydrothermal systems  

NASA Astrophysics Data System (ADS)

The geometric relationship between arc volcanoes and continental hydrothermal systems typically involves a stratovolcano or dome complex with fumaroles at the summit and hydrothermal systems on its flank, and extending outward as much as a few tens of kilometers in some locations. We hypothesize that this association may result from: (1) outward flow of magmatic aqueous fluid from the magma conduit, introducing heat and mass to convecting meteoric water; or (2) circulation of groundwater through crystalline sub- volcanic intrusions, emplaced during previous magmatic activity and unrelated to the current volcanism. We regard the first as more likely because the time scales of the episodic volcanism and hydrothermal activity are consistent with one another (tens of thousands of years), whereas heat extraction from much older subvolcanic intrusions calls for deep circulation in long-cooled rock. Hypothesis 2 is inconsistent with coincident active volcanism and hydrothermal/geothermal activity as observed at Mutnovsky, Kamchatka, Russia where a 62MWe geothermal production facility is ongoing from fluids emanating from a single fracture plane that strikes towards the volcano crater. The geothermal fluid contains water that can be isotopically traced to the Crater Glacier and fumaroles, with temperatures to 600C, >1000 T/d SO2, implying shallow degassing of convecting mafic magma at ~10 m3/sec. This transfer of heat and mass from a magmatic to hydrothermal system is important in the context of geothermal development and hazard monitoring. Important questions raised are: (1) What is the expected lifetime of hydrothermal reservoirs driven by active volcanoes? (2) How is SO2 emission, which is used to assess eruptive potential, modulated by the hydrothermal environment of the magma conduit? (3) To what extent are seismicity and deformation, which are used to forecast eruptions, a response to perturbations from a hydrothermal system rather than to the magma itself? This collaborative project has the following goals: (1) identify magmatic components in fluids proximal to the conduit and their relationship to fluids producing the geothermal system; (2) elucidate the eruption and chemical history of Mutnovsky; (3) monitor and assess hydraulic connectedness of the volcanic and geothermal system; (4) measure in-situ response of the magma- hydrothermal system to earthquakes and eruptions, including precursory changes; (5) determine the overall volatile and thermal budget of Mutnovsky; and (6) quantify the magmatic fluid pathways. An examination of the magma - hydrothermal connection will provide important new data that can be used globally to further geothermal exploration of the proximal region of continental arc volcanoes.

Simon, A.; Eichelberger, J.; West, M.; Ramsey, M.; Newman, A.; Reed, M.; Kiryukhin, A.; Selyangin, O.

2008-12-01

376

Naucleamides A-E, new monoterpene indole alkaloids from Nauclea latifolia.  

PubMed

Five new monoterpene indole alkaloids, naucleamides A-E (1-5), were isolated from the bark and wood of Nauclea latifolia, and the structures and relative stereochemistry were elucidated from the spectroscopic data. Naucleamide E (5) is a unique monoterpene indole alkaloid possessing a pentacyclic ring system with an amino acetal bridge. PMID:12520129

Shigemori, Hideyuki; Kagata, Toshinori; Ishiyama, Haruaki; Morah, Frank; Ohsaki, Ayumi; Kobayashi, Jun'ichi

2003-01-01

377

Studies of the Flickering in Cataclysmic Variables III. The Peculiar Flickering Activity of AE Aquarii  

Microsoft Academic Search

The flaring activity of the unusual cataclysmic variable AE Aqr is investigated using 55 archival light curves. The variance of the data in a given phase interval -- corrected for the influence of noise, ellipsoidal variations and the 33s variation -- is taken as a measure for the activity of the system in that interval. It is found that the

Albert Bruch; Martin Grutter

1997-01-01

378

High Lateral Resolution Auger Electron Spectroscopic (AES) Measurements for Sn Whiskers on Brass  

Microsoft Academic Search

We report high lateral resolution Auger electron spectroscopic (AES) measurements on high aspect ratio Sn whiskers. The whiskers were grown from compressively stressed thin films (~ 6000 ?) of Sn on brass using a magnetron sputtering system. The Auger spectra show that, after sputter cleaning, the whisker is nearly 100% Sn at all locations along the whisker shaft, at the

Michael J. Bozack; Erika R. Crandall; Chad L. Rodekohr; Robert N. Dean; George T. Flowers; Jeffrey C. Suhling

2010-01-01

379

Energy efficiency analysis and implementation of AES on an FPGA  

NASA Astrophysics Data System (ADS)

The Advanced Encryption Standard (AES) was developed by Joan Daemen and Vincent Rjimen and endorsed by the National Institute of Standards and Technology in 2001. It was designed to replace the aging Data Encryption Standard (DES) and be useful for a wide range of applications with varying throughput, area, power dissipation and energy consumption requirements. Field Programmable Gate Arrays (FPGAs) are flexible and reconfigurable integrated circuits that are useful for many different applications including the implementation of AES. Though they are highly flexible, FPGAs are often less efficient than Application Specific Integrated Circuits (ASICs); they tend to operate slower, take up more space and dissipate more power. There have been many FPGA AES implementations that focus on obtaining high throughput or low area usage, but very little research done in the area of low power or energy efficient FPGA based AES; in fact, it is rare for estimates on power dissipation to be made at all. This thesis presents a methodology to evaluate the energy efficiency of FPGA based AES designs and proposes a novel FPGA AES implementation which is highly flexible and energy efficient. The proposed methodology is implemented as part of a novel scripting tool, the AES Energy Analyzer, which is able to fully characterize the power dissipation and energy efficiency of FPGA based AES designs. Additionally, this thesis introduces a new FPGA power reduction technique called Opportunistic Combinational Operand Gating (OCOG) which is used in the proposed energy efficient implementation. The AES Energy Analyzer was able to estimate the power dissipation and energy efficiency of the proposed AES design during its most commonly performed operations. It was found that the proposed implementation consumes less energy per operation than any previous FPGA based AES implementations that included power estimations. Finally, the use of Opportunistic Combinational Operand Gating on an AES cipher was found to reduce its dynamic power consumption by up to 17% when compared to an identical design that did not employ the technique.

Kenney, David

380

Exploration of the Leadership Attributes and Methods Found to Be Associated with Successful Lean System Deployments in Acute Care Hospitals  

Microsoft Academic Search

This study was an exploration of leadership and its relevant association with successful lean system deployments in acute care hospitals. This research investigated the leadership attributes and methods that have been found associated with successful and sustainable lean system transformation efforts. This research employed an exploratory qualitative research design encompassing a preliminary research questionnaire and telephonic interviews of 25 healthcare

Airica D. Steed

2011-01-01

381

Use of modelling to explore the water balance of dryland farming systems in the Murray-Darling Basin, Australia  

Microsoft Academic Search

The Agricultural Production Systems Simulator (APSIM) modelling framework was used to explore components of the water balance for a range of farming systems in the Murray-Darling Basin (MDB) of Australia. Water leaking below the root zone of annual crops and pastures in this region is leading to development of dryland salinity and delivery of salt to waterways. Simulation modelling was

B. A Keating; D Gaydon; N. I Huth; M. E Probert; K Verburg; C. J Smith; W Bond

2002-01-01

382

Marco Polo: International Small Solar System Body Exploration Mission in 2010's  

Microsoft Academic Search

Since 2000, Japanese scientists and engineers have investigated new generation primitive body missions in the post-Hayabusa era in 2010's. Receiving the Minorbody Exploration Forum Final Report, ISAS established the nation-wide Small Body Exploration Working Group (SBE-WG) in 2004. After the successful exploration of the S-type NEO Itokawa by Hayabusa in 2005, the Hayabusa-2 concept emerged for a C-type asteroid sample

Hajime Yano

2008-01-01

383

Directed-polymer systems explored via their quantum analogs: Topological constraints and their consequences  

NASA Astrophysics Data System (ADS)

The equilibrium statistical mechanics of classical directed polymers in two dimensions is well known to be equivalent to the imaginary-time quantum dynamics of a 1+1-dimensional many-particle system, with polymer configurations corresponding to particle world-lines. This equivalence motivates the application of techniques originally designed for one-dimensional many-particle quantum systems to the exploration of many-polymer systems, as first recognized and exploited by de Gennes [J. Chem. Phys.JCPSA60021-960610.1063/1.1669420 48, 2257 (1968)]. In this low-dimensional setting interactions give rise to an emergent polymer fluid, and we examine how topological constraints on this polymer fluid (e.g., due to uncrossable pins or barriers) and their geometry give rise to strong, entropy-driven forces. In the limit of large polymer densities, in which a type of mean-field theory is accurate, we find that a pointlike pin causes a divergent pileup of polymer density on the high-density side of the pin and a zero-density region (or gap) of finite area on the low-density side. In addition, we find that the force acting on a pin that is only mildly displaced from its equilibrium position is sub-Hookean, growing less than linearly with the displacement, and that the gap created by the pin also grows sublinearly with the displacement. By contrast, the forces acting between multiple pins separated along the direction preferred by the polymers are super-Hookean. These nonlinear responses result from effective long-ranged interactions between polymer segments, which emerge via short-ranged interactions between distant segments of long polymer strands. In the present paper, we focus on the case of an infinitely strong, repulsive contact interaction, which ensures that the polymers completely avoid one another. In a companion paper, we consider the effects of a wider set of interpolymer interactions.

Rocklin, D. Zeb; Tan, Shina; Goldbart, Paul M.

2012-10-01

384

The Speedy Magnetic Propeller in the Cataclysmic Variable AE Aquarii  

NASA Astrophysics Data System (ADS)

We present a spectroscopic study of the unusual flaring activity of the cataclysmic variable AE Aqr, which makes use of time-resolved, ultraviolet spectra obtained with the Hubble Space Telescope in November of 1992. This study complements our earlier investigation of the coherent, 33 s oscillations of AE Aqr using the same data. Its scientific objective is to define the ultraviolet spectroscopic properties of the flares and to use them to constrain scenarios for their origin. We find that the UV spectrum of flares features a plethora of emission lines and a prominent Balmer recombination continuum. During flares, the emission-line and continuum fluxes increase by a factor of several, they vary together, with no easily discernible time lag, and proportionally to each other. The radial velocity curves of the stronger ultraviolet lines lead the radial velocity curve of the companion star by about one-third of a cycle, much like the radial velocity curves of the Balmer lines. Our observational results, taken together with other known properties of the system, support a recently proposed scenario in which the accretion flow from the companion star is fragmented into discrete blobs that interact with the speedy propeller that is the magnetosphere of the rapidly spinning white dwarf. Scenarios attributing the flares to coronal activity on the companion star or a magneto spheric gating instability at the white dwarf are ruled out by the data. Their main shortcoming is that they cannot account for the kinematic signature of the line-emitting gas. In the context of the fragmented accretion flow/magnetic propeller scenario we propose that the flares represent the excitation of gaseous blobs upon encounter with the propeller, and their subsequent radiative cooling as as they are expelled from the system. From the data we estimate the mass of a typical blob from which we derive a mean mass transfer rate from the companion star. This mass transfer rate is considerably larger (4 orders of magnitude) than the rate of accretion onto the white dwarf inferred from the X-ray luminosity, as one would expect in the propeller scenario. Moreover, the power expended by the propeller in ejecting most of the matter in the blobs from the system can account for the observed spin-down of the white dwarf. Additional attractive features of this scenario include its ability to explain the observed quasi-periodic oscillations, and the observed pulsed ?-ray emission from AE Aqr.

Eracleous, Michael; Horne, Keith

1996-11-01

385

A CHARGE-COUPLED DEVICE PHOTOMETRIC STUDY OF SOUTH HEMISPHERIC CONTACT BINARY AE PHOENICIS  

SciTech Connect

The complete charge-coupled device light curves in B, V, R, and I bands of the short-period binary system, AE Phe, are presented. It is found that the light curves of AE Phe belong to typical EW-type light variation. Photometric solutions were derived by using the 2003 version of the Wilson-Devinney code. It showed that AE Phe is a W-subtype shallow-contact system (f = 14.6%({+-}0.5%)) with a mass ratio of q = 2.5491({+-}0.0092). The temperature difference between the two components is 227 K. Analysis of the O - C curve suggests that the period of AE Phe shows a long-term continuous increase at a rate of dP/dt = +6.17({+-}0.44) x 10{sup -8} days year{sup -1}. The long-term period increase, the marginal-contact configuration, and the astrophysical parameters of the binary system, all suggest that it is a shallow-contact binary undergoing a thermal relaxation oscillation evolving into a detached binary.

He, J.-J.; Qian, S.-B. [National Astronomical Observatories/Yunnan Observatory, Chinese Academy of Sciences, P.O. Box 110, 650011 Kunming (China); Lajus, E. Fernandez; Farina, C. [Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, 1900 La Plata, Buenos Aires (Argentina)], E-mail: hejiajiacn@gmail.com

2009-11-15

386

Application of Phased-array Vibrator System in shallow oil shale exploration  

NASA Astrophysics Data System (ADS)

Due to the huge oil and gas demands in China, exploration of unconventional oil shale at shallow depths becomes more critical. 52.83% of the identified reserves in China are from Jilin province and Nong'an is one of the main areas of oil shale in Jilin. The average buried depth of oil shale in Nong'an is between 300m and 800m. Since explosive sources are not allowed to operate in civil area and the inconvenience of vibroseis, Phased-array Vibrator System (PAVS) is applied in the exploration of oil shale in Nong'an. We have developed a series electromagnetic Portable High-frequency Vibrator System (PHVS), including single, combination, and phased-array modes. Single mode is the simplest mode, with output force less than 500N, and thus is only suitable for engineering seismic prospecting. Combination mode is a source array, which uses a controller to synchronize all vibrator units and let them work consistently with each other. Thus, it can increase output force than single case. The field test indicates that it can improve signal-to-noise ratio (SNR) of reflected waves in deep layer significantly. However, it contributes little for signals from shallow layers and sometimes it can even deteriorate shallow reflected signals than single source. This is because for signals reflected from shallow depths, the assumption in combination mode that seismic waves propagate along vertical rays is no longer valid. Therefore, they are not stacked constructively. Phased-array mode belongs to a new source array, whose key part is so-called delay/phase controller. By coordinating the signal of each unit using the controller, the seismic waves can be beamed into any interested direction, based on the underground structure and the depth of interested reflected layer. In this case, SNR of the concerned reflected wave can be improved apparently. PHVS in phased-array mode is called PAVS. We made two field tests to evaluate the performance of PAVS. In the first test, we compare PAVS with PHVS in single and combination modes in the Qinjiatun test site. The parameters of PAVS are set as follows: sweep bandwidth of 50~500Hz, 5.3s for the duration of sweep, spacing between adjacent unit is 2m and the number of units is 3; In addition, 5 different delay parameters, 0.802ms, 0.384ms, 0.241ms, 0.174ms, 0.123ms, are used in PAVS test. In this test, we analyzed the signal reflected from the shallowest identified layer to compare the performances of different methods. It showed that 3-unit PAVS improved SNR up to 8.02dB, 6.05dB, 5.03dB, 4.54dB and 4.04dB than single mode, and 4.70dB, 2.74dB, 1.71dB, 1.22dB, 0.72dB higher than the combination case, respectively. For the second test, we made a similar test in Gansu between PAVS and Minivib T15000, which is a hydraulic source with 27kN output force. We set the same control signals to be at 10~120Hz. We observe all signals from electromagnetic vibrators have wider bandwidth than that from hydraulic source, which in turn has a higher resolution. In summary, our results show PAVS can significantly improve the SNR and resolution for shallow reflected layer. Therefore, PAVS is eventually adopted in oil shale exploration in Nong'an. The updated results will be presented in the meeting.

Jiang, T.; Lin, J.; Xu, X.

2011-12-01

387

Exploring Operational Test and Evaluation of Unmanned Aircraft Systems: A Qualitative Case Study  

NASA Astrophysics Data System (ADS)

The purpose of this qualitative case study was to explore and identify strategies that may potentially remedy operational test and evaluation procedures used to evaluate Unmanned Aircraft Systems (UAS) technology. The sample for analysis consisted of organizations testing and evaluating UASs (e.g., U.S. Air Force, U.S. Navy, U.S. Army, U.S. Marine Corps, U.S. Coast Guard, and Customs Border Protection). A purposeful sampling technique was used to select 15 subject matter experts in the field of operational test and evaluation of UASs. A questionnaire was provided to participants to construct a descriptive and robust research. Analysis of responses revealed themes related to each research question. Findings revealed operational testers utilized requirements documents to extrapolate measures for testing UAS technology and develop critical operational issues. The requirements documents were (a) developed without the contribution of stakeholders and operational testers, (b) developed with vague or unrealistic measures, and (c) developed without a systematic method to derive requirements from mission tasks. Four approaches are recommended to develop testable operational requirements and assist operational testers: (a) use a mission task analysis tool to derive requirements for mission essential tasks for the system, (b) exercise collaboration among stakeholders and testers to ensure testable operational requirements based on mission tasks, (c) ensure testable measures are used in requirements documents, and (d) create a repository list of critical operational issues by mission areas. The preparation of operational test and evaluation processes for UAS technology is not uniform across testers. The processes in place are not standardized, thus test plan preparation and reporting are different among participants. A standard method to prepare and report UAS technology should be used when preparing and reporting on UAS technology. Using a systematic process, such as mission-based test design, resonated among participants as an analytical method to link UAS mission tasks and measures of performance to the capabilities of the system under test when developing operational test plans. Further research should examine system engineering designs for system requirements traceability matrix of mission tasks and subtasks while using an analysis tool that adequately evaluates UASs with an acceptable level of confidence in the results.

Saliceti, Jose A.

388

JUpiter ICy moons Explorer (juice): AN ESA L-Class Mission Candidate to the Jupiter System  

NASA Astrophysics Data System (ADS)

The overarching theme for JUICE is: The emergence of habitable worlds around gas giants. Humankind wonders whether the origin of life is unique to the Earth or if it occurs elsewhere in our Solar System or beyond. To answer this question, even though the mechanisms by which life originated on Earth are not yet clearly understood, one can assume that the necessary conditions involve the simultaneous presence of organic compounds, trace elements, water, energy sources and a relative stability of the environment over time. JUICE will address the question: Are there current habitats elsewhere in the Solar System with the necessary conditions (water, biological essential elements, energy and stability) to sustain life? The spatial extent and evolution of habitable zones within the Solar System are critical elements in the development and sustainment of life, as well as in addressing the question of whether life developed on Earth alone or whether it was developed in other Solar System environments and was then imported to Earth. The focus of JUICE is to characterise the conditions that may have led to the emergence of habitable environments among the Jovian icy satellites, with special emphasis on the three ocean-bearing worlds, Ganymede, Europa, and Callisto. Ganymede is identified for detailed investigation since it provides a natural laboratory for analysis of the nature, evolution and potential habitability of icy worlds in general, but also because of the role it plays within the system of Galilean satellites, and its unique magnetic and plasma interactions with the surrounding Jovian environment. For Europa, where two targeted flybys are planned, the focus will be on the chemistry essential to life, including organic molecules, and on understanding the formation of surface features and the composition of the non water-ice material, leading to the identification and characterisation of candidate sites for future in situ exploration. Furthermore, JUICE will provide the first subsurface observations of this icy moon, including the first determination of the minimal thickness of the icy crust over the most recently active regions. JUICE will determine the characteristics of liquid-water oceans below the icy surfaces of the moons. This will lead to an understanding of the possible sources and cycling of chemical and thermal energy, allow investigation of the evolution and chemical composition of the surfaces and of the subsurface oceans, and enable an evaluation of the processes that have affected the satellites and their environments through time. The study of the diversity of the satellite system will be enhanced with additional information gathered remotely on Io and smaller moons. The mis-sion will also focus on characterising the diversity of processes in the Jupiter system which may be required in order to provide a stable environment at Ganymede, Europa and Callisto on geologic time scales, including gravitational coupling between the Galilean satellites and their long term tidal influence on the system as a whole. Focused stud-ies of Jupiter's atmosphere, and magnetosphere and their interaction with the Galilean satellites will further enhance our understanding of the evolution and dynamics of the Jovian system. The circulation, meteorology, chemistry and structure of Jupiter will be studied from the cloud tops to the thermosphere. These observations will be attained over a sufficiently long temporal baseline with broad latitudinal coverage to investigate evolving weather systems and the mechanisms of transporting energy, momentum and material between the different layers. The focus in Jupiter's magnetosphere will include an investigation of the three dimensional properties of the magnetodisc and in-depth study of the coupling processes within the magnetosphere, ionosphere and thermosphere. Aurora and radio emissions and their response to the solar wind will be elucidated.

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

2012-04-01

389

Exploring Europa with a Surface Lander Powered by a Small Radioisotope Power System (RPS)  

Microsoft Academic Search

Europa is a high-priority target for future exploration because of the possibility that it may possess a subsurface liquid ocean that could sustain life. Exploring the surface of this Galilean moon, however, represents a formidable technical challenge due to the great distances involved, the high ambient radiation, and the extremely low surface temperatures. A design concept is presented for a

Robert D. Abelson; James H. Shirley

2005-01-01

390

Exploration and Exploitation Alliances in Biotechnology: A System of New Product Development  

Microsoft Academic Search

We link the exploration--exploitation framework of organizational learning to a technology venture's strategic alliances and argue that the causal relationship between the venture's alliances and its new product development depends on the type of the alliance. In particular, we propose a product development path beginning with exploration alliances predicting products in development, which in turn predict exploitation alliances, and that

Frank T. Rothaermel; David L. Deeds

2004-01-01

391

Ground-based exploration of the outer Solar system by serendipitous stellar occultations  

NASA Astrophysics Data System (ADS)

Serendipitous stellar occultation technique provides a powerful and unique tool to probe the outer Solar system matter, e.g. Kuiper disc and Oort cloud. We present the results of a serendipitous occultation observation campaign carried out with ULTRACAM, mounted on the ESO-VLT telescope, during 2005 May 17-20. The data are processed using the variability index (VI) method modified. The two-colour data set and the VI method allow searching for occulting objects in term of their distance (50, 200 and 5000 au). The analysis of 34 star-hours provide a working data set for assessing an instrumental approach to search for occultation events by trans-Neptunian objects. We performed recovery tests by implanting synthetic profiles in the data and defining the size of detectable objects to achieve a detection rate of 100 per cent. We propose a Fast Multi-Object Photometer (F-MOP) mounted on a 8-m class telescope and examine its performances. Such instrumental approach from the ground is able to exploit the occultation method for the exploration of the trans-Neptunian region, with a high efficiency.

Doressoundiram, A.; Roques, F.; Boissel, Y.; Arenou, F.; Dhillon, V.; Littlefair, Stu; Marsh, T.

2013-01-01

392

Ability Explorer: A Review and Critique.  

ERIC Educational Resources Information Center

|The Ability Explorer (AE) is a newly developed self-report inventory of abilities that is appropriate for group or individual administration. There are machine-scorable and hand-scorable versions of the test, and there are two levels. Level 1 is for students from junior high to high school, and Level 2 is for high school students and adults.

Hoffman, Anne

393

Extreme Ultraviolet Explorer Photometry of RS Canum Venaticorum Systems: Four Flaring Megaseconds  

NASA Astrophysics Data System (ADS)

We present an analysis of 12.2 Ms of Extreme Ultraviolet Explorer (EUVE) photometry of 16 RS CVn systems (including four flaring megaseconds). Our study attempts a systematic categorization of stellar coronal emission in RS CVn binary systems. The temporal resolution of the EUVE satellite and the opportunity for long observations enables us to study separately the quiescent and flaring states of RS CVn systems. Thirty of 31 observations are statistically variable. We examine light curves, characterizing both phase-dependent variations and large- and small-scale flaring. There is evidence for small-scale stochastic variability on the one short-period (P_orb<1 day) system in our sample (ER Vul), which we interpret as small-scale flaring. CF Tuc is the only system for which phase-dependent variations over multiple orbital periods are seen. We analyze 30 flares on nine systems, fitting rise and decay times. Several flares have durations >0.5P_orb and thus cannot originate from compact emission regions close to the stellar surfaces. Many flares have unusual flare morphologies, with rise times comparable to or greater than the decay time, and emission plateaus. In addition, eight flares have decay phases that are fit better by a broken power law than a single power law. The decay times for the second power law are statistically different than the single decay times and are correlated with the flare rise times. This observed connection points to the potential importance of the change in decay rate as a means of examining the physical processes operating during the flare. The distribution of orbital phases of flare onsets on V711 Tau (HR 1099), the best-studied RS CVn in our sample, is consistent with a Poisson distribution that is random in time. In two systems that are partially eclipsing (CF Tuc and ER Vul), we find no evidence for an eclipse in the light curve, indicating that the emission region is large compared to the stellar radius. We parameterize the distribution of flare energies as a power law, finding a cut-off energy of ~10^33 ergs and a slope of -0.6. Flare energy increases with flare duration as E~Deltat^1.42, confirming the long-duration nature of high-energy flares on RS CVn systems. The integrated flare luminosity depends on the quiescent luminosity as L_flare~L^1.05_quiescent. Flare frequencies range from 0.1 day^-1 to 1.5 day^-1. For observations not affected by the dead spot on the Deep Survey detector, 40% of the observed time was spent in a flaring state, indicating that flaring is a ``normal'' state for the coronae of these systems. We note the presence of a quasi-periodicity in EUVE photometric data on the order of 1 day, which is not corrected for in the standard reduction and analysis software.

Osten, Rachel A.; Brown, Alexander

1999-04-01

394

Mars Exploration  

NSDL National Science Digital Library

Mars Exploration is a Windows to the Universe Exploratour and provides information and images about Mariner missions, Viking missions, Mars Observer, Mars Surveyor Program, Mars Pathfinder, Mars Global Surveyor, Mars Polar Lander and Climate Orbiter, Mars 2001, and Mars 2003. Windows to the Universe is a user-friendly learning system pertaining to the Earth and Space sciences. The objective of this project is to develop an innovative and engaging web site that spans the Earth and Space sciences and includes a rich array of documents, including images, movies, animations, and data sets that explore the Earth and Space sciences and the historical and cultural ties between science, exploration and the human experience. Links at the top of each page allow users to navigate between beginner, intermediate, and advanced options for each topic level.

Johnson, Roberta

2000-07-01

395

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

NASA Astrophysics Data System (ADS)

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 Mssbauer spectrometer. In the context of future Mars exploration we present results of Mssbauer analysis of a suite of samples from an iron-rich thermal spring in the Chocolate Pots area of Yellowstone National Park (YNP) and from Obsidian Pool (YNP) and Manitou Springs, Colorado. We have found that Mssbauer spectroscopy can discriminate among the iron-bearing minerals in our samples. Those near the vent and on the surface are identified as ferrihydrite, an amorphous ferric mineraloid. Subsurface samples, collected from cores, which are likely to have undergone inorganic and/or biologically mediated alteration (diagenesis), exhibit spectral signatures that include nontronite (a smectite clay), hematite (?-Fe2O3), small-particle/nanophase goethite (?-FeOOH), and siderite (FeCO3). We find for iron minerals that Mssbauer spectroscopy is at least as efficient in identification as X-ray diffraction. This observation is important from an exploration standpoint. As a planetary surface instrument, Mssbauer spectroscopy can yield high-quality spectral data without sample preparation (backscatter mode). We have also used field emission scanning electron microscopy (FESEM), in conjunction with energy-dispersive X ray (EDX) fluorescence spectroscopy, to characterize the microbiological component of surface sinters and the relation between the microbiological and the mineralogical framework. Evidence is presented that the minerals found in these deposits can have multibillion-year residence times and thus may have survived their possible production in a putative early Martian hot spring up to the present day. Examples include the nanophase property and the Mssbauer signature for siderite, which has been identified in a 2.09-billion-year old hematite-rich chert stromatolite. Our research demonstrates that in situ Mssbauer spectroscopy can help determine whether hydrothermal mineral deposits exist on Mars, which is significant for exobiology because of the issue of whether that world ever had conditions conducive to the origin of life. As a useful tool for selection of samples suitable for transport to Earth, Mssbauer spectroscopy will not only serve geological interests but will also have potential for exopaleontology.

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

1999-04-01

396

Surface images of the short period contact binary AE Phe  

NASA Astrophysics Data System (ADS)

We present high resolution Doppler images of the short period (P = 0.362 d) contact binary AE Phe. Using least squares deconvolution, we make use of the information content of the several thousand lines in each chelle spectrum to obtain the necessary S/N and time resolution required to resolve individual starspot features. A single pair of rotationally broadened profiles (free of sidelobes due to blending) with a typical S/N of 3000 - 4000 per spectrum is thus obtained. With 300 sec exposures we achieve a cadence of 350 sec which is equivalent to sampling the rotation phase every 4 . We derive images for four nights of data which reveal starspots at most latitudes on both components of the common envelope system. Individual starspots evolve significantly on very short timescales, of order one day; significantly faster than the week timescales found on active single stars and the Sun.

Barnes, J. R.; Lister, T. A.; Hilditch, R. W.; Collier Cameron, A.

2004-03-01

397

Low-dimensional chaos in magnetospheric activity from AE time series  

Microsoft Academic Search

The magnetospheric response to the solar wind input, as represented by the time series measurements of the AE index, has been examined using phase space reconstruction techniques. The system was found to behave as a low-dimensional chaotic system with a fractal dimension of 3.6 and has a Kolmogorov entropy <0.2\\/min. These are indicative that the dynamics of the system can

D. V. Vassiliadis; A. S. Sharma; T. E. Eastman; K. Papadopoulos

1990-01-01

398

Lunar Solar Power System Driven Human Development of the Moon and Resource-Rich Exploration of the Inner Solar System  

NASA Astrophysics Data System (ADS)

The people of Earth require, by the middle of the 21st century, a new source of commercial power that is sustainable, clean, reliable, low in cost (< 1 cent per kilowatt electric hour), not disruptive of the biosphere, and at least 4 to 5 times more abundant (> 2 kWe/person or > 20 TWe) than now (1, 2). The Lunar Solar Power (LSP) System appears to be the only reasonable option (2, 3). The Moon dependably receives 13,000 TWs of solar power. The LSP System consists of pairs of power bases located on opposite limbs of the Moon as seen from Earth. The power bases collect the solar energy and convert it to beams of microwaves. The microwaves are delivered directly to moonward-facing receivers on Earth or indirectly through relay satellites in orbit about Earth. To achieve low cost, the power bases are made primarily of local lunar materials by machines, facilities, and people deployed from Earth. Hundreds to thousands of people will be required on the Moon, in cis-lunar space, and operating tele-robotically from Earth to construct the full scale LSP System. Models indicate that power sales on Earth can easily support the required people, their regular transport between the Earth and Moon, and provide the required return on investment to develop the LSP System (4, 5). Construction of the LSP System, even at an early stage, creates fundamentally new wealth and capabilities supportive of rapid growth of human activities within the inner solar system. A factor of ten increase in global Earth-to-orbit transport will be required in the demonstration phase. Launch cost of 5,000 /kg is acceptable. Lower cost transport decreases the upfront cost of the LSP System but is not critical to the cost of energy from the mature LSP. Logistic and assembly facilities in orbit about the Earth and Moon will be required that are at least a factor of ten large than planned for the full scale International Space Station. Transport must be provided between the Earth and the Moon of hundreds, possibly thousands, of workers. Production machinery will be available that can build fundamentally new infrastructure from the common silicate materials of asteroids and the moons of Mars. Commercial power can be beamed from the Moon to ion-propelled rockets and to industrial facilities throughout the inner solar systems (6, 7). The LSP System can establish the Earth and the Moon as a two-planet economy. Lunar and cis-lunar industry will grow through profitable activities. Exploration of the inner solar system can stage, at marginal cost, from the Moon and cis-lunar space rather than the surface of Earth. 1. World Energy Council (2000) Energy for Tomorrow's World - Acting Now!, 175pp., Atalink Projects Ltd, London. 2. Criswell, David R. (2001) Lunar Solar Power System: Industrial Research, Development, and Demonstration, Session 1.2.2: Hydroelectricity, Nuclear Energy and New Renewables, 18th World Energy Congress. [http://www.wec.co.uk] 3. Strong, Marice (2001) Where on Earth are We Going?, (See p. 351-352), 419pp., Random House (forward by Kofi Annan) 4. Criswell, D. R. And R. D. Waldron (1993), "International lunar base and the lunar-based power system to supply Earth with electric power," Acta Astronautica, 29, No. 6: 469-480. 5. Criswell, D. R. (1998), Lunar Solar Power: Lunar unit processes, scales, and challenges, 6 p.p. (ms), ExploSpace: Workshop on Space Exploration and Resources Exploitation, European Space Agency, Cagliari, Sardinia, (October 20 - 22). 6. Criswell, D. R. (1999), Commercial lunar solar power and sustainable growth of the two-planet economy, Proc. Third International Working Group on Lunar Exploration and Exploitation, Solar System Research, Vol. 33, #5, 356-362, Moscow, (October 11-14). 7. Criswell, D.R. 2000 (October) Commercial power for Earth and lunar industrial development, 7pp., 51st Congress of the International Astronautical Federation (IAF). (Rio de Janeiro, Brazil). Paper #IAA-00-IAA.13.2.06.

Criswell, D. R.

2002-01-01

399

Planetary Science E/PO in 2012: The Year of the Solar System, Fifty Years of Solar System Exploration, and More  

NASA Astrophysics Data System (ADS)

The successful Year of the Solar System E/PO program will be followed by one themed to Fifty Years of Solar System Exploration. These programs, key astronomical events, and other factors will make 2012 a banner year for solar system programming.

Williams, S. H.

2012-03-01

400

AES crypto chip utilizing high-speed parallel pipelined architecture  

Microsoft Academic Search

In November 2001, the National Institute of Standards and Technology (NIST) of the USA chose the Rijndael algorithm as the suitable Advanced Encryption Standard (AES) to replace the Data Encryption Standard (DES) algorithm. Since then, many hardware implementations have been proposed in literature. We present a hardware-efficient design increasing throughput for the AES algorithm using a high-speed parallel pipelined architecture.

Deen Kotturi; Seong-moo Yoo; John Blizzard

2005-01-01

401

Based MATLAB on Advanced Encryption Standard (AES) IP Validation  

Microsoft Academic Search

This paper describers the validation of AES IP Core, based matlab2007a. There are many authors (Saqib et al., 2003) have discussed the detailing implementation of AES IP core; but this paper mainly emphasizes portability and flexibility in the validation of the Verilog IP codes.

Xinsheng Wang; Liang Han; Chenxu Wang; Xiaoning Liu

2008-01-01

402

Highly secured high throughput VLSI architecture for AES algorithm  

Microsoft Academic Search

This paper provides an efficient VLSI architecture to increase the throughput and security of the Advanced Encryption Standard (AES) Algorithm. The existing architecture provide the Look up Table technique for the Subbytes and inverse Subbytes transformation used in AES algorithm, our proposed technique uses combinational circuit and pipelining technique which increase the throughput and reduce the delay. This design proposes

M. Vanitha; R. Sakthivel; Subha

2012-01-01

403

AES Greenidge Bioethanol Co-Location Assessment: Final Report.  

National Technical Information Service (NTIS)

The feasibility of co-locating a cellulose-to-ethanol (bioethanol) facility at the existing AES Greenidge coal-fired electric power plant near Dresden, New York, has been evaluated in this study. The AES Greenidge facility currently obtains 8 to 10% of it...

2002-01-01

404

Correlation dimension and affinity of AE data and bicolored noise  

Microsoft Academic Search

A detailed analysis of several periods of the AE time series is performed. Bicolored noise was generated, and it is shown to have many properties in common with the AE data. The use of the Grassberger and Procaccia (1983) algorithm indicates saturation at a low dimension for both data, but the use of a modified integral does not. The self-affinity

J. Takalo; J. Timonen; H. Koskinen

1993-01-01

405

Power-Analysis Attack on an ASIC AES implementation  

Microsoft Academic Search

The AES (Advanced Encryption Standard) is a new block cipher standard published by the US government in Novem- ber 2001. As a consequence, there is a growing interest in efficient implementations of the AES. For many appli- cations, these implementations need to be resistant against side channel attacks, that is, it should not be too easy to extract secret information

Siddika Berna rs; Frank K. Grkaynak; Elisabeth Oswald; Bart Preneel

2004-01-01

406

A prototype visualization tool for exploring mass variations in the Earth system  

NASA Astrophysics Data System (ADS)

In many scientific environments, scientists face two major difficulties in observing spatial and temporal dynamics of geo processes. First, measurements of an observable usually contain a superposition of signals of interest; the interpretation of a measurement therefore requires scientists to simultaneously assess multiple complementary observables and/or simulate the processes generating the signals. Second, many quantities of interest cannot be directly measured but need to be inferred from a limited amount of observables. Here we present a prototype visualization tool for supporting scientists in exploring the spatial and temporal mass change variations within System Earth. Mass change cannot be measured directly but need to be derived from satellite measurements of the Earth's gravity field. The first visualization shows the simulated mass anomaly (here, with respect to the annual mean), and the second visualization shows the calculated gravity field taking the simulated mass change as input data. The third visualization shows the mass change inverted from the measured gravity field of the Earth as input that is shown in the fourth visualization. Individual components of the simulated mass change arising from different subsystems can be (de)selected and the imprint in the gravity field is visualized. The user can navigate through time, as well as zooming and rotating of the spheres and adjustment of the color scale are possible. The behavior of all four spheres is synchronized. The combined representations of these visual views supports scientists 1) assess the overall quality of the modeled versus the observed gravity field signals, 2) determine the influence of different processes to the measured variation of the Earth's gravity field in the region of interest, and to understand which fine-grained variation in the mass change cannot be inferred from the satellite measurements. This presentation will present the prototype visualization tool and provide a discussion on how our it supports geoscientists to study the relationship between simulated and mass change variation recovered from the Earth's gravity field.

Rawald, Tobias; Sasgen, Ingo; Unger, Andrea; Sips, Mike

2013-04-01

407

NASA radiation belt models AP-8 and AE-8  

NASA Astrophysics Data System (ADS)

Empirical models AP-8 and AE-8 for the trapped protons and electrons in the Earth's radiation belts are currently available from NSSDC. These are the culmination of a series of models developed by J. I. Vette and colleagues. The initial models were begun in the mid-sixties with the most recent model, AE-8, being released in 1980. These models are based on data ranging from 1958 to 1970. They have been well documented by TREND, a group working under a contract with ESA, contains some information on this model. The only models which are still available from NSSDC are the most recent proton and electron models AP-8 and AE-8. A brief summary is presented of the modeling efforts to date based on information from Lemaire, Spjeldvik, and Rothwell. Results from AE8MAX, results from the models previously used at GL (AE6MAX + AEI7HI), and results from code provided by NSSDC are compared.

Jordan, Carolyn E.

1989-09-01

408

Exploring Performance Benefits from Multiple Satellite Systems and Multiple Carrier Signals Using GPS and Virtual Galileo Measurements  

Microsoft Academic Search

The next generation GNSSs, such as the modernized GPS and Glonass, and the planned Galileo systems, offer three or more carrier frequencies for civilian use. This paper explores the performance benefits that the multiple satellite constellations and multiple carrier signals can bring to next generation GNSS services at global and regional scales. The well known benefits of multiple GNSS constellations

Yanming Feng; Chris Rizos

2006-01-01

409

Exploring the perceptions of Knowledge Management and Knowledge Management Systems: A case study on the Libyan oil industry  

Microsoft Academic Search

The aim of this research is to investigate the importance of Knowledge Management (KM) and Knowledge Management Systems (KMS) in the oil and gas industry of Libya. It explores their purposes, significance, activities, functions and barriers. The aim is to obtain and share the efficient and effective management strategies, policies and methods in order to support local partners. Data for

Eltayeb Mohamed Elgobbi

2010-01-01

410

Hands-on Activities for Exploring the Solar System in K-14 Formal and Informal Education Settings  

Microsoft Academic Search

Introduction: Activities developed by NASA scientists and teachers focus on integrating Planetary Science activities with existing Earth science, math, and language arts curriculum. Educators may choose activities that fit a particular concept or theme within their curriculum from activities that highlight missions and research pertaining to exploring the solar system. Most of the activities use simple, inexpensive techniques that help

J. S. Allen; K. W. Tobola

2004-01-01

411

An Exploration of the Leadership Style Preferences among African American Women Administrators of the 1890 Cooperative Extension System  

ERIC Educational Resources Information Center

The purpose of this mixed-methods study was to identify and explore the leadership style preferences among current African American Administrators of the 1890 Land-Grant Cooperative Extension system. The population used in this study was African American women administrators from eighteen mostly southern states. The researcher used a "two-phase

Campbell, Shelvy L.

2010-01-01

412

Where Do I Stand?: An Exploration of the Rules That Regulate Victim Participation in the Criminal Justice System  

Microsoft Academic Search

The victims' rights movement has helped promote opportunities for victim participation within the criminal justice system. One such opportunity, the creation and delivery of a victim impact statement, has generated significant empirical attention. Most of this research explores the effects of participation on specific outcomes (e.g., sentencing, victim satisfaction). Yet relatively little is known about the implementation of victim participation

Christine M. Englebrecht

2012-01-01

413

Lithosphere tectonics and thermo-mechanical properties: An integrated modelling approach for Enhanced Geothermal Systems exploration in Europe  

Microsoft Academic Search

Knowledge of temperature at drillable depth is a prerequisite in site selection for geothermal exploration and development of enhanced geothermal systems (EGS). Equally important, the thermo-mechanical signature of the lithosphere and crust provides critical constraints for the crustal stress field and basement temperatures where borehole observations are rare. The stress and temperature field in Europe is subject to strong spatial

S. Cloetingh; J. D. van Wees; P. A. Ziegler; L. Lenkey; F. Beekman; M. Tesauro; A. Frster; B. Norden; M. Kaban; N. Hardebol; D. Bont; A. Genter; L. Guillou-Frottier; M. Ter Voorde; D. Sokoutis; E. Willingshofer; T. Cornu; G. Worum

2010-01-01

414

Exploring the Role of Particle Shape in the Ordering of a Simulated 2D Hard Particle System  

NASA Astrophysics Data System (ADS)

Inspired by recent experiments (Narayan et. al, J. Stat. Mech 2006 P01005 (2006), and Narayan et. al, Science 317, 105 (2007)) demonstrating the role of particle shape in a swarming, granular nematic, we perform simulations of 2D hard particles using an improved Monte Carlo procedure, exploring the effects of varying particle end-shape and aspect ratio on ordering in this system.

Blair, Donald

2010-03-01

415

A study of variable thrust, variable specific impulse trajectories for solar system exploration  

NASA Astrophysics Data System (ADS)

A study has been performed to determine the advantages and disadvantages of variable thrust and variable Isp (specific impulse) trajectories for solar system exploration. There have been several numerical research efforts for variable thrust, variable Isp, power-limited trajectory optimization problems. All of these results conclude that variable thrust, variable Isp (variable specific impulse, or VSI) engines are superior to constant thrust, constant Isp (constant specific impulse; or CSI) engines. However, most of these research efforts assume a mission from Earth to Mars, and some of them further assume that these planets are circular and coplanar. Hence they still lack the generality. This research has been conducted to answer the following questions: (1) Is a VSI engine always better than a CSI engine or a high thrust engine for any mission to any planet with any time of flight considering lower propellant mass as the sole criterion? (2) If a planetary swing-by is used for a VSI trajectory, is the fuel savings of a VSI swing-by trajectory better than that of a CSI swing-by or high thrust swing-by trajectory? To support this research, an unique, new computer-based interplanetary trajectory calculation program has been created. This program utilizes a calculus of variations algorithm to perform overall optimization of thrust, Isp, and thrust vector direction along a trajectory that minimizes fuel consumption for interplanetary travel. It is assumed that the propulsion system is power-limited, and thus the compromise between thrust and Isp is a variable to be optimized along the flight path. This program is capable of optimizing not only variable thrust trajectories but also constant thrust trajectories in 3-D space using a planetary ephemeris database. It is also capable of conducting planetary swing-bys. Using this program, various Earth-originating trajectories have been investigated and the optimized results have been compared to traditional CSI and high thrust trajectory solutions. Results show that VSI rocket engines reduce fuel requirements for any mission compared to CSI rocket engines. Fuel can be saved by applying swing-by maneuvers for VSI engines; but the effects of swing-bys due to VSI engines are smaller than that of CSI or high thrust engines.

Sakai, Tadashi

416

PDS 144: THE FIRST CONFIRMED Herbig Ae-Herbig Ae WIDE BINARY  

SciTech Connect

PDS 144 is a pair of Herbig Ae stars that are separated by 5.''35 on the sky. It has previously been shown to have an A2Ve Herbig Ae star viewed at 83 Degree-Sign inclination as its northern member and an A5Ve Herbig Ae star as its southern member. Direct imagery revealed a disk occulting PDS 144 N-the first edge-on disk observed around a Herbig Ae star. The lack of an obvious disk in direct imagery suggested PDS 144 S might be viewed face-on or not physically associated with PDS 144 N. Multi-epoch Hubble Space Telescope imagery of PDS 144 with a 5 year baseline demonstrates PDS 144 N and S are comoving and have a common proper motion with TYC 6782-878-1. TYC 6782-878-1 has previously been identified as a member of Upper Sco sub-association A at d = 145 {+-} 2 pc with an age of 5-10 Myr. Ground-based imagery reveals jets and a string of Herbig-Haro knots extending 13' (possibly further) which are aligned to within 7 Degree-Sign {+-} 6 Degree-Sign on the sky. By combining proper motion data and the absence of a dark mid-plane with radial velocity data, we measure the inclination of PDS 144 S to be i = 73 Degree-Sign {+-} 7 Degree-Sign . The radial velocity of the jets from PDS 144 N and S indicates they, and therefore their disks, are misaligned by 25 Degree-Sign {+-} 9 Degree-Sign . This degree of misalignment is similar to that seen in T Tauri wide binaries.

Hornbeck, J. B.; Williger, G. M.; Lauroesch, J. T. [Department of Physics and Astronomy, University of Louisville, Louisville, KY 40292 (United States); Grady, C. A. [Eureka Scientific, 2452 Delmer St. Suite 100, Oakland, CA 96402 (United States); Perrin, M. D.; Grogin, N. A. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Wisniewski, J. P.; Tofflemire, B. M. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Brown, A. [CASA, University of Colorado, Boulder, CO 80309-0593 (United States); Holtzman, J. A.; Arraki, K. [Department of Astronomy, New Mexico State University, Dept 4500, Box 30001, Las Cruces, NM 88003 (United States); Hamaguchi, K. [CRESST and X-Ray Astrophysics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Woodgate, B.; Petre, R.; Bonfield, D. G. [NASA's Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Daly, B. [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States)

2012-01-01

417

The molecular effects of aloe-emodin (AE)/liposome-AE on human nonmelanoma skin cancer cells and skin permeation.  

PubMed

In this study, aloe-emodin (AE) was less cytotoxic to human noncancerous skin cells (premalignant keratinocytic HaCaT and fibroblast Hs68) than to nonmelanoma cancer cells (epidermoid carcinoma A431 and head and neck squamous cell carcinoma SCC25). Notably, AE induced apoptosis by up-regulating tumor necrosis factor-alpha and Fas ligand and their cognate receptors, downstream adaptor TNF-R1-associated death domain and Fas-associated death domain, and activated caspase-8 in A431 and SCC25 cells. Moreover, AE up-regulated p53, increased intracellular reactive oxygen species levels, depleted intracellular-reduced GSH, up-regulated cytochrome c and Bax, down-regulated Bcl-2, and activated caspase-9 and -3. The combinatory use of AE and 5-fluorouracil (5-Fu) achieved significantly more cell death in A431 and SCC25 cells than only the use of AE or 5-Fu, likely via regulation of caspase-8, -9, and -3 expressions. Incorporating AE into the liposomal formulation accelerated cell death of A431 and SCC25 cells within a short time. Furthermore, skin permeation profiles of drug suggest that the liposomal formulation enhances transdermal delivery of AE. Experimental data demonstrate the feasibility of applying liposome to deliver AE in clinical therapy. PMID:19928967

Chou, Tzung-Han; Liang, Chia-Hua

2009-12-01

418

Phase-Space Density Analysis of the AE-8 Traped Electron and the AP-8 Trapped Proton Model Environments  

SciTech Connect

The AE-8 trapped electron and the AP-8 trapped proton models are used to examine the L-shell variation of phase-space densities for sets of transverse (or 1st) invariants, {mu}, and geometrical invariants, K (related to the first two adiabatic invariants). The motivation for this study is twofold: first, to discover the functional dependence of the phase-space density upon the invariants; and, second, to explore the global structure of the radiation belts within this context. Variation due to particle rest mass is considered as well. The overall goal of this work is to provide a framework for analyzing energetic particle data collected by instruments on Global Positioning System (GPS) spacecraft that fly through the most intense region of the radiation belt. For all considered values of {mu} and K, and for 3.5 R{sub E} < L < 6.5 R{sub E}, the AE-8 electron phase-space density increases with increasing L; this trend--the expected one for a population diffusing inward from an external source--continues to L = 7.5 R{sub E} for both small and large values of K but reverses slightly for intermediate values of K. The AP-8 proton phase-space density exhibits {mu}-dependent local minima around L = 5 R{sub E}. Both AE-8 and AP-8 exhibit critical or cutoff values for the invariants beyond which the flux and therefore the phase-space density vanish. For both electrons and protons, these cutoff values vary systematically with magnetic moment and L-shell and are smaller than those estimated for the atmospheric loss cone. For large magnetic moments, for both electrons and protons, the K-dependence of the phase-space density is exponential, with maxima at the magnetic equator (K = 0) and vanishing beyond a cutoff value, K{sub c}. Such features suggest that momentum-dependent trapping boundaries, perhaps drift-type loss cones, serve as boundary conditions for trapped electrons as well as trapped protons.

Thomas E. Cayton

2005-08-01

419

Phase-Space Density Analyses of the AE-8 Trapped Electron and the AP-8 Trapped Proton Model Environments  

SciTech Connect

The AE-8 trapped electron and the AP-8 trapped proton models are used to examine the L-shell variation of phase-space densities for sets of transverse (or 1st) invariants, {mu}, and geometrical invariants, K (related to the first two adiabatic invariants). The motivation for this study is twofold: first, to discover the functional dependence of the phase-space density upon the invariants; and, second, to explore the global structure of the radiation belts within this context. Variation due to particle rest mass is considered as well. The overall goal of this work is to provide a framework for analyzing energetic particle data collected by instruments on Global Positioning System (GPS) spacecraft that fly through the most intense region of the radiation belt. For all considered values of {mu} and K, and for 3.5 R{sub E} < L < 6.5 R{sub E}, the AE-8 electron phase-space density increases with increasing L; this trend--the expected one for a population diffusing inward from an external source--continues to L = 7.5 R{sub E} for both small and large values of K but reverses slightly for intermediate values of K. The AP-8 proton phase-space density exhibits {mu}-dependent local minima around L = 5 R{sub E}. Both AE-8 and AP-8 exhibit critical or cutoff values for the invariants beyond which the flux and therefore the phase-space density vanish. For both electrons and protons, these cutoff values vary systematically with magnetic moment and L-shell and are smaller than those estimated for the atmospheric loss cone. For large magnetic moments, for both electrons and protons, the K-dependence of the phase-space density is exponential, with maxima at the magnetic equator (K = 0) and vanishing beyond a cutoff value, K{sub c}. Such features suggest that momentum-dependent trapping boundaries, perhaps drift-type loss cones, serve as boundary conditions for trapped electrons as well as trapped protons.

T.E. Cayton

2005-08-12

420

Towards Developing an Automated Science Analysis System for Mars Surface Exploration.  

NASA Astrophysics Data System (ADS)

We are continuing development of algorithms that will facilitate development of automated systems to assist robotic or human explorers in identifying rocks and minerals in the field. Over the past year, we have focused on algorithms with the ability to identify igneous rocks from images and spectra and on building our database of rocks and minerals. Our collection currently contains over 700 igneous, sedimentary, metamorphic rocks and mineral samples that we have identified, analyzed, and imaged. Images are taken under controlled lighting and at fixed distances. We are in the process of obtaining Raman and visible, near- and mid-infrared spectra of the entire collection to help identify the minerals that comprise the samples. Analysis of both the physical properties and the relative mineral abundances of a sample form the basis of rock identification and classification. This extensive dataset allows us to optimize and test the algorithms under a variety of conditions. We will report on the current ability of our algorithms to identify and discriminate rock types with a variety of input data. When considering color only, using the weighted k-nearest neighbors approach, the algorithm correctly identified greater than 70% of the felsic rocks, at least 70% of the intermediate rocks, and greater than 80% of the mafic rocks. Using a similar approach for texture, the algorithm correctly identified 85% of the plutonic rocks and 76% of the volcanic rocks. We have used both Bayesian and Decision Tree automated reasoning approaches to combine the results of the color and texture algorithms. Based on our tests to date, the Decision Tree method has given the best results, correctly identifying at least 80% of granites and granodiorites and greater than 70% of andesites and basalts using color and texture algorithms combined. In addition to the generally better performance, the Decision Tree method has the advantage of allowing one to trace back the algorithm's line of reasoning in reaching a final identification. Since a hierarchical method more closely follows the line of reasoning used by practicing geologists, we feel it may meet with greater acceptance in spacecraft and field applications. We are continuing to improve our algorithms and will report on their current state of development.

Gulick, V. C.; Shi, X.; Hart, S. D.; Horton, A.

2003-12-01

421

Determination of Isotopic and Total Thorium at Ultra-Trace Level in Water by Alpha - Spectroscopy and Micro-Injection ICP-AES.  

National Technical Information Service (NTIS)

A sequential method for the determination of isotopic and total thorium has been developed. The method is based on the combination of thorium preconcentration, high resolution alpha - spectroscopy processes and, the use of ICP-AES system. This method perm...

N. Miekeley M. G. R. Vale C. L. P. Silveira

1987-01-01

422

Restoring the Rule of Law: Reflections on Fixing the Immigration System and Exploring Failed Policy Choices  

Microsoft Academic Search

This paper reflects on issues surrounding the current debate about immigration reform, and explores failed policy choices over the past twenty years. It sets the stage first by providing a historical perspective, and noting how the events of 9\\/11 have inexorably changed the rhetoric and tone of the political and policy debates over immigration. It speculates about legislative choices and

Katherine L. Vaughns

2005-01-01

423

Exploration and exploitation in innovation systems: The case of pharmaceutical biotechnology  

Microsoft Academic Search

This paper develops a theoretical framework for an explanation of how exploitation and exploration build on each other, in a cycle of discovery, developed in earlier research. The framework is tested empirically, in the sense of seeing whether it can help to reconstruct and understand the emergence of the pharmaceutical industry. One of the conclusions is that whereas recent literature

Victor Gilsing; Bart Nooteboom

2006-01-01

424

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

Microsoft Academic Search

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

1998-01-01

425

Behavior of Rare Earth Elements in Geothermal Systems: A New Exploration/Exploitation Tool.  

National Technical Information Service (NTIS)

The goal of this four-year project was to provide a database by which to judge the utility of the rare earth elements (REE) in the exploration for and exploitation of geothermal fields in the United States. Geothermal fluids from hot springs and wells hav...

S. A. Wood

2001-01-01

426

Sexual Offences against Children: An Exploration of Attrition in the Northern Ireland Criminal Justice System  

ERIC Educational Resources Information Center

|Objective: This paper uses data provided by the Police Service for Northern Ireland (PSNI) to compare the characteristics and outcomes of reported sexual offences involving child and adult victims and explore the factors associated with case outcomes. Method: PSNI provided data on 8,789 sexual offences recorded between April 2001 and March 2006.

Bunting, Lisa

2008-01-01

427

Genotypic Prediction of HIV-1 CRF01-AE Tropism  

PubMed Central

HIV-1 subtype CRF01-AE predominates in south Asia and has spread throughout the world. The virus tropism must be determined before using CCR5 antagonists. Genotypic methods could be used, but the prediction algorithms may be inaccurate for non-B subtypes like CRF01-AE and the correlation with the phenotypic approach has not been assessed. We analyzed 61 CRF01-AE V3 clonal sequences of known phenotype from the GenBank database. The sensitivity of the Geno2pheno10 genotypic algorithm was 91%, but its specificity was poor (54%). In contrast, the combined 11/25 and net charge rule was highly specific (98%) but rather insensitive (64%). We thus identified subtype CRF01-AE determinants in the V3 region that are associated with CXCR4 use and developed a new simple rule for optimizing the genotypic prediction of CRF01-AE tropism. The concordance between the predicted CRF01-AE genotype and the phenotype was 95% for the clonal data set. We then validated this algorithm by analyzing the data from 44 patients infected with subtype CRF01-AE, whose tropism was determined using a recombinant phenotypic entry assay and V3-loop bulk sequencing. The CRF01-AE genotypic tool was 70% sensitive and 96% specific for predicting CXCR4 use, and the concordance between genotype and phenotype was 84%, approaching the concordance obtained for predicting the tropism of HIV-1 subtype B. Genotypic predictions that use a subtype CRF01-AE-specific algorithm appear to be preferable for characterizing coreceptor usage both in pathophysiological studies and for ensuring the appropriate use of CCR5 antagonists.

Delobel, Pierre; Rogez, Sylvie; Encinas, Stephanie; Bruel, Patrick; Pasquier, Christophe; Sandres-Saune, Karine; Marchou, Bruno; Massip, Patrice; Izopet, Jacques

2013-01-01

428

Threshold exploration of enterprise system co-evolution under strategic perspective  

Microsoft Academic Search

Through analyzing enterprise system operation rules based on synergetics theory, this paper aims to decide the strategic input of enterprise system. In synergetics, enterprise system's threshold reveal the relationship between external control variables and state variables of enterprise systems, which could be reached by changing control variables. And then, the enterprise system would be able to achieve the self-organization evolution

Zhang Tie-nan; Han Bing

2009-01-01

429

Mars Exploration with Directed Aerial Robot Explorers  

Microsoft Academic Search

Global Aerospace Corporation (GAC) is developing a revolutionary system architecture for exploration of planetary atmospheres and surfaces from atmospheric altitudes. The work is supported by the NASA Institute for Advanced Concepts (NIAC). The innovative system architecture relies upon the use of Directed Aerial Robot Explorers (DAREs), which essentially are long-duration-flight autonomous balloons with trajectory control capabilities that can deploy swarms

Alexey A. Pankine; Kim M. Aaron; Matthew K. Heun; Kerry T. Nock; R. Stephen Schlaifer; Andrew P. Ingersoll; Ralph D. Lorenz

2004-01-01

430

Autonomous Hopping Robotic Systems: Long Range Mobility and Extended Lifetime for Planetary Exploration  

NASA Astrophysics Data System (ADS)

There is significant potential for more mobile planetary surface science exploration vehicles. This is especially true for Mars, where the ability to cross challenging terrain, access areas of higher elevation, visit diverse geological regions and perform long traverses of up to 200 km supports the search for past water and life. Vehicles capable of a ballistic 'hop' have been proposed in the past, but proposals using in-situ acquired propellants offer the prospect of a significant step change in planetary exploration. This paper considers a mission concept termed "Mars Reconnaissance Lander". An approach is described for a mission where planetary science requirements that cannot be met by a conventional rover and are used to derive vehicle and mission requirements.

Ambrosi, R.; Williams, H. R.; Bridges, J. C.; Bannister, N. P.; Perkinson, M.-C.; Reed, J.; Peacocke, L.; Stuttard, M.; Howe, S. D.; O'Brien, R. C.; Klein, A. C.

2012-09-01

431

HRSCview: a web-based data exploration system for the Mars Express HRSC instrument  

NASA Astrophysics Data System (ADS)

The High Resolution Stereo Camera (HRSC) on the ESA Mars Express spacecraft has been orbiting Mars since January 2004. By spring 2007 it had returned around 2 terabytes of image data, covering around 35% of the Martian surface in stereo and colour at a resolu-tion of 10-20 m/pixel. HRSCview provides a rapid means to explore these images up to their full resolu-tion with the data-subsetting, sub-sampling, stretching and compositing being carried out on-the-fly by the image server. It is a joint website of the Free University of Berlin and the German Aerospace Center (DLR). The system operates by on-the-fly processing of the six HRSC level-4 image products: the map-projected ortho-rectified nadir pan-chromatic and four colour channels, and the stereo-derived DTM (digital terrain model). The user generates a request via the web-page for an image with several parameters: the centre of the view in surface coordinates, the image resolution in metres/pixel, the image dimensions, and one of several colour modes. If there is HRSC coverage at the given location, the necessary segments are extracted from the full orbit images, resampled to the required resolution, and composited according to the user's choice. In all modes the nadir channel, which has the highest resolu-tion, is included in the composite so that the maximum detail is always retained. The images are stretched ac-cording to the current view: this applies to the eleva-tion colour scale, as well as the nadir brightness and the colour channels. There are modes for raw colour, stretched colour, enhanced colour (exaggerated colour differences), and a synthetic 'Mars-like' colour stretch. A colour ratio mode is given as an alternative way to examine colour differences (R=IR/R, G=R/G and B=G/B). The final image is packaged as a JPEG file and returned to the user over the web. Each request requires approximately 1 second to process. A link is provided from each view to a data product page, where header items describing the full map-projected science data product are displayed, and a direct link to the archived data products on the ESA Planetary Science Archive (PSA) is provided. At pre-sent the majority of the elevation composites are de-rived from the HRSC Preliminary 200m DTMs gener-ated at the German Aerospace Center (DLR), which will not be available as separately downloadable data products. These DTMs are being progressively super-seded by systematically generated higher resolution archival DTMs, also from DLR, which will become available for download through the PSA, and be simi-larly accessible via HRSCview. At the time of writing this abstract (May 2007), four such high resolution DTMs are available for download via the HRSCview data product pages (for images from orbits 0572, 0905, 1004, and 2039).

Michael, G.; Walter, S.; Neukum, G.

2007-08-01

432

Distributed design-space exploration for high-level synthesis systems  

Microsoft Academic Search

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

Rajiv Dutta; Jayanta Roy; Ranga Vemuri

1992-01-01

433

Terrigenous clastic depositional systems. Applications to petroleum, coal and uranium exploration  

SciTech Connect

Two experts in fundamental and applied sedimentology and sedimentary economic geology provide a state-of-the-art summary of clastic depositional environments and their associated mineral fuel deposits. Utilizing a multidisciplinary approach, the authors focus on the recognition, mapping, and three-dimensional reconstruction of clastic deposits, primarily from subsurface data, examine the hydrology of sedimentary basins, and discuss applications of genetic facies analysis to mineral fuel resource appraisal, exploration, and development.

Galloway, W.E.; Hobday, D.K.

1983-01-01

434

Miniature high-resolution imaging system with 3D MOEMS beam scanning for Mars exploration  

Microsoft Academic Search

A compact confocal imaging instrument is described that makes use of a high-performance bi-axial Silicon torsion mirror, in concert with a reflective dynamic parabolic membrane mirror to provide 3D beam scanning. This beam scan engine is incorporated into a confocal imaging Raman spectrometer under development for exploration of Martian rocks and soil, designed to achieve optical resolution of 1 micrometers

David L. Dickensheets; Phillip A. Himmer; Robert A. Friholm; B. J. Lutzenberger

2000-01-01

435

System support for exploration and expert feedback in resolving conflicts during integration of metadata  

Microsoft Academic Search

A critical reality in integration is that knowledge obtained from different sources may often be conflicting. Conflict-resolution,\\u000a whether performed during the design phase or during run-time, can be costly and, if done without a proper understanding of\\u000a the usage context, can be ineffective. In this paper, we propose a novel exploration and feedback-based approach [FICSR (Pronounced as fixer)] to conflict-resolution

K. Seluk Candan; Huiping Cao; Yan Qi; Maria Luisa Sapino

2008-01-01

436

PRELIMINARY RESULTS FROM NEOWISE: AN ENHANCEMENT TO THE WIDE-FIELD INFRARED SURVEY EXPLORER FOR SOLAR SYSTEM SCIENCE  

SciTech Connect

The Wide-field Infrared Survey Explorer (WISE) has surveyed the entire sky at four infrared wavelengths with greatly improved sensitivity and spatial resolution compared to its predecessors, the Infrared Astronomical Satellite and the Cosmic Background Explorer. NASA's Planetary Science Division has funded an enhancement to the WISE data processing system called 'NEOWISE' that allows detection and archiving of moving objects found in the WISE data. NEOWISE has mined the WISE images for a wide array of small bodies in our solar system, including near-Earth objects (NEOs), Main Belt asteroids, comets, Trojans, and Centaurs. By the end of survey operations in 2011 February, NEOWISE identified over 157,000 asteroids, including more than 500 NEOs and {approx}120 comets. The NEOWISE data set will enable a panoply of new scientific investigations.

Mainzer, A.; Bauer, J.; Masiero, J.; Eisenhardt, P. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Grav, T. [Department of Astronomy, Johns Hopkins University, Baltimore, MD (United States); Cutri, R. M.; Dailey, J.; Alles, R.; Beck, R.; Brandenburg, H.; Conrow, T.; Evans, T.; Fowler, J.; Jarrett, T. [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); McMillan, R. S. [Lunar and Planetary Laboratory, University of Arizona, 1629 East University Boulevard, Kuiper Space Science Bldg. 92, Tucson, AZ 85721-0092 (United States); Wright, E. [UCLA Astronomy, P.O. Box 91547, Los Angeles, CA 90095-1547 (United States); Walker, R. [Monterey Institute for Research in Astronomy, Monterey, CA (United States); Jedicke, R.; Tholen, D. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Spahr, T., E-mail: amainzer@jpl.nasa.gov [Minor Planet Center, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

2011-04-10

437

Preliminary Results from NEOWISE: An Enhancement to the Wide-field Infrared Survey Explorer for Solar System Science  

NASA Astrophysics Data System (ADS)

The Wide-field Infrared Survey Explorer (WISE) has surveyed the entire sky at four infrared wavelengths with greatly improved sensitivity and spatial resolution compared to its predecessors, the Infrared Astronomical Satellite and the Cosmic Background Explorer. NASA's Planetary Science Division has funded an enhancement to the WISE data processing system called "NEOWISE" that allows detection and archiving of moving objects found in the WISE data. NEOWISE has mined the WISE images for a wide array of small bodies in our solar system, including near-Earth objects (NEOs), Main Belt asteroids, comets, Trojans, and Centaurs. By the end of survey operations in 2011 February, NEOWISE identified over 157,000 asteroids, including more than 500 NEOs and ~120 comets. The NEOWISE data set will enable a panoply of new scientific investigations.

Mainzer, A.; Bauer, J.; Grav, T.; Masiero, J.; Cutri, R. M.; Dailey, J.; Eisenhardt, P.; McMillan, R. S.; Wright, E.; Walker, R.; Jedicke, R.; Spahr, T.; Tholen, D.; Alles, R.; Beck, R.; Brandenburg, H.; Conrow, T.; Evans, T.; Fowler, J.; Jarrett, T.; Marsh, K.; Masci, F.; McCallon, H.; Wheelock, S.; Wittman, M.; Wyatt, P.; DeBaun, E.; Elliott, G.; Elsbury, D.; Gautier, T., IV; Gomillion, S.; Leisawitz, D.; Maleszewski, C.; Micheli, M.; Wilkins, A.

2011-04-01

438

Quantitative AES (Auger Electron Spectroscopy): The Establishment of a Standard Reference Spectrum for the Accurate Determination of Spectrometer Transmission Functions,  

National Technical Information Service (NTIS)

The precise shape of the whole electron spectrum in AES is defined by (i) the physics of the process, and (ii) the intensity/energy transmission function of the measurement system. In many systems item (ii) is uncharacterized and surveys show variable eff...

G. C. Smith M. P. Seah

1987-01-01

439

New concepts in exploring subsalt Paleozoic hydrocarbon systems in mature and near producing areas of Morocco  

Microsoft Academic Search

The subsalt Paleozoic hydrocarbon systems are one of the areally largest and paradoxally the least drilled in Morocco. Although, worldwide, these systems contain the largest potential gas reserves and contain one of the largest emerging oil plays and better still the few wells drilled to test the system in Essaouira Basin are producing commercial wet gas, these systems have never

H. Jabour; A. Deminati; M. Hcaine; M. El Alji

1996-01-01

440

Accelerating AES Using Instruction Set Extensions for Elliptic Curve Cryptography  

Microsoft Academic Search

The Advanced Encryption Standard (AES) specifies an al- gorithm for a symmetric-key cryptosystem that has already found wide adoption in security applications. A substantial part of the AES algo- rithm are the MixColumns and InvMixColumns operations, which in- volve multiplications in the binary extension field GF(28). Recently pro- posed instruction set extensions for elliptic curve cryptography (ECC) include custom instructions

Stefan Tillich; Johann Groschdl

2005-01-01

441

The Disk and Environment of Herbig Ae Star HD 100453  

Microsoft Academic Search

We present a multi-wavelength examination of the inner disk and environment of the near-ZAMS Herbig Ae star HD 100453. Chandra ACIS-S imagery shows that the Herbig Ae star has Lx=2.6x1029 erg s-1, with Lx\\/Lbol and a pulse height spectrum similar to beta Pic Moving Group early F stars. In addition to the previously noted deficit of warm dust, the inner

Karen Collins; C. Grady; J. P. Wisniewski; K. Hamaguchi; R. van Boekel; S. Brittain; A. Carmona; G. Williger; M. van den Ancker; M. Sitko; W. J. Carpenter; B. Woodgate; T. Henning; R. Petre

2007-01-01

442

Secure and Efficient Masking of AES { A Mission Impossible?  

Microsoft Academic Search

This document discusses masking approaches with a special focus on the AES S-box. Firstly, we discuss previously presented masking schemes with respect to their security and implementation. We conclude that algorithmic countermeasures to secure the AES algorithm against side-channel attacks have not been resistant against all flrst-order side-channel attacks. In this article, we introduce a new masking countermeasure which is

Elisabeth Oswald; Stefan Mangard; Norbert Pramstaller

443

Fault Based Cryptanalysis of the Advanced Encryption Standard (AES)  

Microsoft Academic Search

In this paper we describe several fault attacks on the Ad- vanced Encryption Standard (AES). First, using optical\\/eddy current fault induction attacks as recently publicly presented by Skorobogatov, Anderson and Quisquater, Samyde (SA,QS), we present an implemen- tation independent fault attack on AES. This attack is able to deter- mine the complete 128-bit secret key of a sealed tamper-proof smart-

Johannes Blmer; Jean-pierre Seifert

2003-01-01

444

High-speed VLSI architectures for the AES algorithm  

Microsoft Academic Search

This paper presents novel high-speed architectures for the hardware implementation of the Advanced Encryption Standard (AES) algorithm. Unlike previous works which rely on look-up tables to implement t