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NASA NTRS2005

The hindlimb unloading rat model: literature overview, technique update and comparison with space flight data

The hindlimb unloading rodent model is used extensively to study the response of many physiological systems to certain aspects of space flight, as well as to disuse and recovery from disuse for Earth benefits. This chapter describes the evolution of hindlimb unloading, and is divided into three sections. The first section examines the characteristics of 1064 articles using or reviewing the hindlimb unloading model, published between 1976 and April 1, 2004. The characteristics include number of publications, journals, countries, major physiological systems, method modifications, species, gender, genetic strains and ages of rodents, experiment duration, and countermeasures. The second section provides a comparison of results between space flown and hindlimb unloading animals from the 14-day Cosmos 2044 mission. The final section describes modifications to hindlimb unloading required by different experimental paradigms and a method to protect the tail harness for long duration studies. Hindlimb unloading in rodents has enabled improved understanding of the responses of the musculoskeletal, cardiovascular, immune, renal, neural, metabolic, and reproductive systems to unloading and/or to reloading on Earth with implications for both long-duration human space flight and disuse on Earth.

Flight Experiment↗
NASA NTRS2005

Demonstration of Four Operating Capabilities to Enable a Small Aircraft Transportation System

The Small Aircraft Transportation System (SATS) project has been a five-year effort fostering research and development that could lead to the transformation of our country s air transportation system. It has become evident that our commercial air transportation system is reaching its peak in terms of capacity, with numerous delays in the system and the demand keeps steadily increasing. The SATS vision is to increase mobility in our nation s transportation system by expanding access to more than 3400 small community airports that are currently under-utilized. The SATS project has focused its efforts on four key operating capabilities that have addressed new emerging technologies and procedures to pave the way for a new way of air travel. The four key operating capabilities are: Higher Volume Operations at Non-Towered/Non-Radar Airports, En Route Procedures and Systems for Integrated Fleet Operations, Lower Landing Minimums at Minimally Equipped Landing Facilities, and Increased Single Pilot Performance. These four capabilities are key to enabling low-cost, on-demand, point-to-point transportation of goods and passengers utilizing small aircraft operating from small airports. The focus of this paper is to discuss the technical and operational feasibility of the four operating capabilities and demonstrate how they can enable a small aircraft transportation system.

Viken, Sally A.↗
NASA NTRS2005

Models for Water Isotopes Constrained with Data from Crystal Face

During the year covered by this proposal we conducted work on several different topics, as reflected by our publications listed below. One major activity was to work with a group of about 10 scientists from around the country to prepare a science-planning document (Tropical Composition, Cloud and Climate Coupling Experiment (TC4)) that outlined the rationale, locations, strategy to accomplish the goals, and possible payloads for a set of three tropical missions. We also prepared background materials for various NRAs being prepared at NASA Headquarters for missions in Costa Rica, Darwin and Guam. Unfortunately budgetary constraints prevented these missions from moving forward. In conjunction with the group NASA Ames we built a new numerical model for deep convection and have applied that model to simulate the CRYSTAL isotope data. Our goal in particular has been to better understanding how convection distributes water vapor isotopes. CRYSTAL observations of water isotopes are very different from those suggested by previous workers who assumed the isotopes would obey Rayleigh fractionation. The water isotope study has several implications. First it is a check on the realism of the deep convection model. Second, the isotopes are a measure of the precipitation removal in the atmosphere. Hence they provide a constraint on a parameter that is difficult to otherwise measure. Finally it has been suggested that isotopes may be the key to unraveling the water transport into the stratosphere and upper troposphere. Such transport is critical both for the radiation balance and for stratospheric chemistry. Ours is the first model that is able to treat this transport. Our initial results are now in press in Geophys. Res. Lett. Essentially we are able to explain the vertical profiles of isotopes in the tropical tropopause transition layer. We are also able to account for stratospheric humidity ana isotope abundances with this model. The data suggest that isotopes do not provide a clear constraint on the mechanism by which water enters the stratosphere- whether by convection, or by slow ascent. Our work is relevant for the water isotope comparison experiments recently done by NASA. We are conducting numerical experiments related to this project to help understand that data.

Toon, Owen B.↗
NASA NTRS2005

Projected Regional Climate in 2025 Due to Urban Growth

By 2025, 60 to 80 percent of the world s population will live in urban environments. Additionally, the following facts published by the United Nations further illustrates how cities will evolve in the future. Urban areas in the developing world are growing very rapidly. The urban growth rate will continue to be particularly rapid in the urban areas of less developed regions, averaging 2.4 per cent per year during 2000-2030, consistent with a doubling time of 29 years. The urbanization process will continue worldwide. The concentration of population in cities is expected to continue so that, by 2030, 84 percent of the inhabitants of more developed countries will be urban dwellers. Urbanization impacts the whole hierarchy of human settlements. In 2000,24.8 per cent of the world population lived in urban settlements with fewer than 500,000 inhabitants and by 2015 that proportion will likely rise to 27.1 per cent.

Shepherd, J. Marshall↗
NASA NTRS2005

Strawman Philosophical Guide for Developing International Network of GPM GV Sites

The creation of an international network of ground validation (GV) sites that will support the Global Precipitation Measurement (GPM) Mission's international science programme will require detailed planning of mechanisms for exchanging technical information, GV data products, and scientific results. An important component of the planning will be the philosophical guide under which the network will grow and emerge as a successful element of the GPM Mission. This philosophical guide should be able to serve the mission in developing scientific pathways for ground validation research which will ensure the highest possible quality measurement record of global precipitation products. The philosophical issues, in this regard, partly stem from the financial architecture under which the GV network will be developed, i.e., each participating country will provide its own financial support through committed institutions -- regardless of whether a national or international space agency is involved.At the 1st International GPM Ground Validation Workshop held in Abingdon, UK in November-2003, most of the basic tenants behind the development of the international GV network were identified and discussed. Therefore, with this progress in mind, this presentation is intended to put forth a strawman philosophical guide supporting the development of the international network of GPM GV sites, noting that the initial progress has been reported in the Proceedings of the 1st International GPM GV Workshop -- available online. The central philosophical issues themselves, all flow from the fact that each participating institution can only bring to the table, GV facilities and scientific personnel that are affordable to the sanctioning (funding) national agency (be that a research, research-support, or operational agency). This situation imposes on the network, heterogeneity in the measuring sensors, data collection periods, data collection procedures, data latencies, and data reporting capabilities. Therefore, in order for the network to be effective in supporting the central scientific goals of the GPM mission, there must be a basic agreed upon doctrine under which the network participants function vis-a-vis: (1) an overriding set of general scientific requirements, (2) a minimal set of policies governing the free flow of GV data between the scientific participants, (3) a few basic definitions concerning the prioritization of measurements and their respective value to the mission, (4) a few basic procedures concerning data formats, data reporting procedures, data access, and data archiving, and (5) a simple means to differentiate GV sites according to their level of effort and ability to perform near real-time data acquisition - data reporting tasks. Most important, in case they choose to operate as a near real-time data collection-data distribution site, they would be expected to operate under a fairly narrowly defined protocol needed to ensure smooth GV support operations. This presentation will suggest measures responsive to items (1) - (5) from which to proceed,. In addition, this presentation will seek to stimulate discussion and debate concerning how much heterogeneity is tolerable within the eventual GV site network, given that the any individual GV site can only be considered scientifically useful if it supports the achievement of the central GPM Mission goals. Only ground validation research that has a direct connection to the space mission should be considered justifiable given the overarching scientific goals of the mission. Therefore each site will have to seek some level of accommodation to what the GPM Mission requires in the way of retrieval error characterization, retrieval error detection and reporting, and generation of GV data products that support assessment and improvement of the mission's standard precipitation retrieval algorithms. These are all important scientific issues that will be best resolved in open scientific debate.

Smith, Eric A.↗
NASA NTRS2006

Updraft Model for Development of Autonomous Soaring Uninhabited Air Vehicles

Large birds and glider pilots commonly use updrafts caused by convection in the lower atmosphere to extend flight duration, increase cross-country speed, improve range, or simply to conserve energy. Uninhabited air vehicles may also have the ability to exploit updrafts to improve performance. An updraft model was developed at NASA Dryden Flight Research Center (Edwards, California) to investigate the use of convective lift for uninhabited air vehicles in desert regions. Balloon and surface measurements obtained at the National Oceanic and Atmospheric Administration Surface Radiation station (Desert Rock, Nevada) enabled the model development. The data were used to create a statistical representation of the convective velocity scale, w*, and the convective mixing-layer thickness, zi. These parameters were then used to determine updraft size, vertical velocity profile, spacing, and maximum height. This paper gives a complete description of the updraft model and its derivation. Computer code for running the model is also given in conjunction with a check case for model verification.

Allen, Michael J.↗
NASA NTRS2005

Contingency Operations Support to NASA Johnson Space Center Medical Operations Division

The Wyle Laboratories Contingency Operations Group provides support to the NASA Johnson Space Center (JSC) Medical Operations Division in the event of a space flight vehicle accident or JSC mishap. Support includes development of Emergency Medical System (EMS) requirements, procedures, training briefings and real-time support of mishap investigations. The Contingency Operations Group is compliant with NASA documentation that provides guidance in these areas and maintains contact with the United States Department of Defense (DOD) to remain current on military plans to support NASA. The contingency group also participates in Space Operations Medical Support Training Courses (SOMSTC) and represents the NASA JSC Medical Operations Division at contingency exercises conducted worldwide by the DOD or NASA. The events of September 11, 2001 have changed how this country prepares and protects itself from possible terrorist attacks on high-profile targets. As a result, JSC is now considered a high-profile target and thus, must prepare for and develop a response to a Weapons of Mass Destruction (WMD) incident. The Wyle Laboratories Contingency Operations Group supports this plan, specifically the medical response, by providing expertise and manpower.

Stepaniak, Philip↗
NASA NTRS2006

Remote sensing of tropospheric constituents by OMI on the EOS Aura satellite

The Ozone Monitoring Instrument (OMI) was launched on NASA's EOS Aura satellite in July 2004. This instrument was built in the Netherlands with collaboration with Finland. The science data products are being developed jointly by scientists from the three countries. OMI is the first instrument to combine the high spatial resolution daily global mapping capability of TOMS with high spectral resolution measurements necessary for retrieving a number of trace gases of relevance to atmospheric chemistry, using techniques pioneered by GOME. In this talk I will show what our planet looks like at UV wavelengths and what these data can tell us about the effects of human activities on global air quality and climate.

Bhartia, Pawan K.↗
NASA NTRS2006

Constellation Operations: Lessons Learned For Future Exploration

The Earth science community has long advocated placing numerous instruments in space to study the Earth and its environment. Space agencies from many countries have responded to this call with a wide range of orbiting satellites. Scientists also envisioned placing some satellites in constellations, to enable diverse remote sensing instruments to observe the same part of the Earth (or its atmosphere) at about the same time, thereby increasing the opportunities for coincident science observations. The Earth Science Afternoon Constellation is answering this call, but there have been unique challenges on the way to its deployment. Currently, the Afternoon Constellation is to comprise six satellites. Three are currently on orbit: NASA's Earth Observing System (EOS)-Aqua (2002) and EOS-Aura (2004), and CNES's Polarization & Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar (PARASOL) (2004). Two more satellites, the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) and Cloudsat, are to be jointly launched in late 2005, followed by the Orbiting Carbon Observatory (OCO) in 2008. The Afternoon Constellation is unlike most satellite constellations in that: 1) It is not a homogenous mix of identical satellites; rather it comprises several satellites with complementary observational capabilities; 2) The satellites are not spaced around the Earth to provide instantaneous, global coverage (as for a communications satellite constellation); rather they orbit in close proximity so observations occur at about the same time over approximately the same region; and 3) Lastly, the satellites are not managed and controlled by one organization; rather the list of organizations is diverse: CNES in France, NASA Centers at Goddard, Langley, and the Jet Propulsion Laboratory, and the US Air Force facility in New Mexico. The PARASOL launch and early orbit (L&EO) phase proved to be a learning experience for constellation members (including Constellation management). Prior to launch, all members signed an operations coordination document that spelled out basic requirements for keeping the constellation safe and resolving non-nominal events. Once PARASOL reached orbit and the mission teams gained experience using the newly-developed constellation monitoring tools, it became clear that some of the guidelines in the signed agreements had to be adjusted. This paper presents the L&EO lessons learned and how they were used to prepare for the next phase - the period following the CloudSat/CALIPSO launch.

Kelly, Angelita C.↗
NASA NTRS2006

Verification, Validation, and Accreditation Challenges of Distributed Simulation for Space Exploration Technology

Throughout its rich history, NASA has invested heavily in sophisticated simulation capabilities. These capabilities reside in NASA facilities across the country - and with partners around the world. NASA s Exploration Systems Mission Directorate (ESMD) has the opportunity to leverage these considerable investments to resolve technical questions relating to its missions. The distributed nature of the assets, both in terms of geography and organization, present challenges to their combined and coordinated use, but precedents of geographically distributed real-time simulations exist. This paper will show how technological advances in simulation can be employed to address the issues associated with netting NASA simulation assets.

Thomas, Danny↗
NASA NTRS2005

Discovering the Regulatory Considerations of the Federal Aviation Administration: Interviewing the Aviation Rulemaking Advisory Committee

Maintenance Resource Management (MRM) training for aviation mechanics has become mandatory in many industrialized countries since 1998. Yet, to date, MRM training remains optional in the U.S. Interestingly, a similar safety discipline, namely Crew/Cockpit Resource Management (CRM), is mandatory for pilots, flight engineers, flight attendants, and dispatchers and is regulated in the Federal Aviation Administration s (FAA) Federal Aviation Regulations (FARs). If MRM training is important to enhance aviation technicians working behavior, the rationale to not regulate it opens a window for study. This research aims to inductively investigate the FAA s regulatory rationale concerning MRM training based on direct inputs from the FAA s Aviation Rulemaking Advisory Committee (ARAC) members. Delphi methodology associated with purposive sampling technique was adopted. The result revealed that the FAA cannot regulate MRM because the aviation industry is strongly opposed to it due to the lack of training budgets, the need of a quantifiable cost-effect analysis, concern over the FAA s inspection workforce, an ongoing voluntary alternative called the Air Transportation Surveillance System (ATOS), the government s lower priority on maintenance after 9/11, and the airlines tight embracement of operational flexibility without regulation.

Lu, Chien-tsung↗
NASA NTRS2000

Terrain Perception for DEMO III

The Demo III program has as its primary focus the development of autonomous mobility for a small rugged cross country vehicle. In this paper we report recent progress on both stereo-based obstacle detection and terrain cover color-based classification.

autonomous navigation color classification terrain↗
NASA NTRS1999

Stereo Vision Based Velocity Control

The next phase of the unmanned ground vehicle development sponsored by OSD calls for intelligent velocity control to support cross-country driving speeds of 10 mph by day and 5 mph by night.

vision speed control spline↗
NASA NTRS1998

Digital Audio Broadcasting in the Short Wave Bands

For many decades the Short Wae broadcasting service has used high power, double-sideband AM signals to reach audiences far and wide. While audio quality was usually not very high, inexpensive receivers could be used to tune into broadcasts fro distant countries.

Broadcasting Digital Audio↗
NASA NTRS1997

(abstract) Survey of Volcanic Hazards in the Trans Mexican Volcanic Belt

A substantial percentage of the world's population lives in areas vulnerable to the negative effects of future volcanic activity. This is especially true in Mexico, where within the Trans Mexican Volcanic Belt (TMVB) one half of the country's 90 million inhabitants live. The TMVB is a 1 000 by 200 km area, dotted with hundreds of volcanoes and volcanic centers. Most of the area has been poorly studied, and the volcanic history is largely unknown. Our approach is to combine interpretations of satellite images, field work and mapping, laboratory analysis, and age dating to elucidate the volcanic history and evaluate the potential eruptive hazards. Hazards evaluations are done in the form of risk maps.

Volcanic Belt TMVB volcanic history↗
NASA NTRS1996

Mars Together 2001: Joint US-Russian Team

While the US and USSR have collaborated in human space flight and Earth application missions, this is the first time in the cultural relations between our two countries that American and Russian specialists have been authorized to work together on a joint space science mission. A study was commissioned to investigate the possibility of a combined US/Russian mission in the 2001 opportunity. A basic option for a proposed mission (abbreviated as MT 2001) was adopted. This option is described.

Mars Russia↗
NASA NTRS1995

Future Technologies for Earth Science with Spaceborne GPS

Spaceborne Global Positioning System (GPS) receivers will one day make important contributions to atmospheric, ionospheric, and solid Earth science. A number of GPS microsatellite missions are already in preparation in several countries. These missions require GPS flight receivers with capabilities well beyond the needs of most space missions. Receiver and microsatellite future technology is discussed.

remote sensing geodesy geophysics microsatellites ↗
NASA NTRS2006

Experiences in managing the Prometheus Project

Congress authorized NASA?s Prometheus Project in February 2003, with the first Prometheus mission slated to explore the icy moons of Jupiter. The Project had two major objectives: (1) to develop a nuclear reactor that would provide unprecedented levels of power and show that it could be processed safely and operated reliably in space for long-duration, deep-space exploration and (2) to explore the three icy moons of Jupiter - Callisto, Ganymede, and Europa - and return science data that would meet the scientific goals as set forth in the Decadal Survey Report of the National Academy of Sciences. Early in Project planning, it was determined that the development of the Prometheus nuclear powered Spaceship would be complex and require the intellectual knowledge residing at numerous organizations across the country. In addition, because of the complex nature of the Project and the multiple partners, approaches beyond those successfully used to manage a typical JPL project would be needed. This paper1 will describe the key experiences in managing Prometheus that should prove useful for future projects of similar scope and magnitude

nuclear↗