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A general overview of the USGS land remote sensing program is presented. The contents include: 1) Brief overview of USGS land remote sensing program; 2) Highlights of JACIE work at USGS; 3) Update on NASA/USGS Landsat Data Continuity Mission; and 4) Notes on alternative data sources.
Operational products used by the U.S. Federal Aviation Administration to alert pilots of hazardous icing provide nowcast and short-term forecast estimates of the potential for the presence of supercooled liquid water and supercooled large droplets. The Current Icing Product (CIP) system employs basic satellite-derived information, including a cloud mask and cloud top temperature estimates, together with multiple other data sources to produce a gridded, three-dimensional, hourly depiction of icing probability and severity. Advanced satellite-derived cloud products developed at the NASA Langley Research Center (LaRC) provide a more detailed description of cloud properties (primarily at cloud top) compared to the basic satellite-derived information used currently in CIP. Cloud hydrometeor phase, liquid water path, cloud effective temperature, and cloud top height as estimated by the LaRC algorithms are into the CIP fuzzy logic scheme and a confidence value is determined. Examples of CIP products before and after the integration of the LaRC satellite-derived products will be presented at the conference.
A method and system is disclosed which provides precise multi-function digitally implementable modulation for a communication system. The invention provides a modulation signal for a communication system in response to an input signal from a data source. A digitized time response is generated from samples of a time domain representation of a spectrum profile of a selected modulation scheme. The invention generates and stores coefficients for each input symbol in accordance with the selected modulation scheme. The output signal is provided by a plurality of samples, each sample being generated by summing the products of a predetermined number of the coefficients and a predetermined number of the samples of the digitized time response. In a specific illustrative implementation, the samples of the output signals are converted to analog signals, filtered and used to modulate a carrier in a conventional manner. The invention is versatile in that it allows for the storage of the digitized time responses and corresponding coefficient lookup table of a number of modulation schemes, any of which may then be selected for use in accordance with the teachings of the invention.
HELIX-Atlanta was developed to support current and future state and local EPHT programs to implement data linking demonstration projects which could be part of the CDC EPHT Network. HELIX-Atlanta is a pilot linking project in Atlanta for CDC to learn about the challenges the states will encounter. NASA/MSFC and the CDC are partners in linking environmental and health data to enhance public health surveillance. ~ The use of NASA technology creates value added geospatial products from existing environmental data sources to facilitate public health linkages. Proving the feasibility of the approach is the main objective
HELIX-Atlanta was developed to support current and future state and local EPHT programs to implement data linking demonstratio'n projects which could be part of the EPHT Network. HELIX-Atlanta is a pilot linking project in Atlanta for CDC to learn about the challenges the states will encounter. NASA/MSFC and the CDC are partners in linking environmental and health data to enhance public health surveillance. The use of NASA technology creates value - added geospatial products from existing environmental data sources to facilitate public health linkages. Proving the feasibility of the approach is the main objective
The ULTOR(Registered TradeMark) Passive Pose and Position Engine (P3E) technology, developed by Advanced Optical Systems, Inc (AOS), uses real-time image correlation to provide relative position and pose data for spacecraft guidance, navigation, and control. Potential data sources include a wide variety of sensors, including visible and infrared cameras. ULTOR(Registered TradeMark) P3E has been demonstrated on a number of host processing platforms. NASA is integrating ULTOR(Registerd TradeMark) P3E into its Relative Navigation System (RNS), which is being developed for the upcoming Hubble Space Telescope (HST) Servicing Mission 4 (SM4). During SM4 ULTOR(Registered TradeMark) P3E will perform realtime pose and position measurements during both the approach and departure phases of the mission. This paper describes the RNS implementation of ULTOR(Registered TradeMark) P3E, and presents results from NASA's hardware-in-the-loop simulation testing against the HST mockup.
The Sequence History Update Tool performs Web-based sequence statistics archiving for Mars Reconnaissance Orbiter (MRO). Using a single UNIX command, the software takes advantage of sequencing conventions to automatically extract the needed statistics from multiple files. This information is then used to populate a PHP database, which is then seamlessly formatted into a dynamic Web page. This tool replaces a previous tedious and error-prone process of manually editing HTML code to construct a Web-based table. Because the tool manages all of the statistics gathering and file delivery to and from multiple data sources spread across multiple servers, there is also a considerable time and effort savings. With the use of The Sequence History Update Tool what previously took minutes is now done in less than 30 seconds, and now provides a more accurate archival record of the sequence commanding for MRO.
The Hurricane Imaging Radiometer (HIRAD) is a new airborne microwave remote sensor currently under development to enhance real-time hurricane ocean surface wind observations. HIRAD builds on the capabilities of the Stepped Frequency Microwave Radiometer (SFMR), which now operates on NOAA P-3, G-4, and AFRC C-130 aircraft. Unlike the SFMR, which measures wind speed and rain rate along the ground track directly beneath the aircraft, HIRAD will provide images of the surface wind and rain field over a wide swath (approximately 3 times the aircraft altitude). To demonstrate potential improvement in the measurement of peak hurricane winds, we present a set of Observing System Simulation Experiments (OSSEs) in which measurements from the new instrument as well as those from existing platforms (air, surface, and space-based) are simulated from the output of a high-resolution (approximately 1.7 km) numerical model. Simulated retrieval errors due to both instrument noise as well as model function accuracy are considered over the expected range of incidence angles, wind speeds and rain rates. Based on numerous simulated flight patterns and data source combinations, statistics are developed to describe relationships between the observed and true (from the model s perspective) peak wind speed. These results have implications for improving the estimation of hurricane intensity (as defined by the peak sustained wind anywhere in the storm), which may often go un-observed due to sampling limitations.
Space mission planning often involves long-term storage of volatile liquids or high-pressure gases. These may include cryogenic fuels and oxidizers, high-pressure gases, and life-support-critical consumables. The risk associated with the storage of fluids and gases in space systems has long been an issue and the ability to retain these fluids is often tied to mission success. A leak in the storage or distribution system can cause many different problems, including a simple, but mission endangering, loss of inventory or, in severe cases, unbalanced thrust loads on a flight vehicle. Cryogenic propellants are especially difficult to store, especially over a long duration. The propellant can boil off and be lost through the insulating walls of the tank or simple thermal cycling of the fittings, valves, and propellant feed lines may unseat seals allowing the fluid to escape. Current NASA missions call for long-duration in-space storage of propellants, oxidizers, and life support supplies. Leaks of a scale detectable through a pressure drop in the storage tank are often catastrophic and have long been the focus of ground-based mitigation efforts where redundant systems are often employed. However, there is presently no technology available for detecting and monitoring low-level, but still mission-endangering, gas leaks in space. Standard in-space gas detection methods either have a very limited pressure range over which they operate effectively or are limited to certain gases. Mass spectrometer systems are able to perform the detection tasks, but their size, mass and use of high voltage, which could potentially lead to an arc that ignites a combustible propellent, severely limit their usefulness in a space system. In this paper, we present results from testing of the light-based interferometric gas monitoring and leak detection sensor shown in Fig. 1. The output of the sensor is an interference fringe pattern that is a function of the gas density, and commensurate index of refraction, in the sample region. Changes in the density of gas cause the interference fringes to move across a photodiode detector, providing a temporal history of the leak. The sensor is fiber coupled and constructed from solid optics, allowing for placement almost anywhere on the spacecraft. It is also advantageous in that it consumes very little power and does not introduce an ignition source. Data are presented demonstrating the capability of the sensor to measure density variations in different gas species. In addition, the transient response of the sensor in vacuum is demonstrated. These data extend and improve upon the results previously presented by the authors in Ref. [1].
This paper presents a data analysis of the Surface Management System (SMS) performance of departure events, including push-back and runway departure events.The paper focuses on the detection performance, or the ability to detect departure events, as well as the prediction performance of SMS. The results detail a modest overall detection performance of push-back events and a significantly high overall detection performance of runway departure events. The overall detection performance of SMS for push-back events is approximately 55%.The overall detection performance of SMS for runway departure events nears 100%. This paper also presents the overall SMS prediction performance for runway departure events as well as the timeliness of the Aircraft Situation Display for Industry data source for SMS predictions.
The Shuttle is a very reliable vehicle in comparison with other launch systems. Much of the risk posed by Shuttle operations is related to fundamental aspects of the spacecraft design and the environments in which it operates. It is unlikely that significant design improvements can be implemented to address these risks prior to the end of the Shuttle program. The model will continue to be used to identify possible emerging risk drivers and allow management to make risk-informed decisions on future missions. Potential uses of the SPRA in the future include: - Calculate risk impact of various mission contingencies (e.g. late inspection, crew rescue, etc.). - Assessing the risk impact of various trade studies (e.g. flow control valves). - Support risk analysis on mission specific events, such as in flight anomalies. - Serve as a guiding star and data source for future NASA programs.
The Mark 5C disk-based VLBI data system is being developed as the third-generation Mark 5 disk-based system, increasing the sustained data-recording rate capability to 4 Gbps. It is built on the same basic platform as the Mark 5A, Mark 5B and Mark 5B+ systems and will use the same 8-disk modules as earlier Mark 5 systems, although two 8-disk modules will be necessary to support the 4 Gbps rate. Unlike its earlier brethren, which use proprietary data interfaces, the Mark 5C will accept data from a standard 10 Gigabit Ethernet connection and be compatible with the emerging VLBI Data Interchange Format (VDIF) standard. Data sources for the Mark 5C system will be based on new digital backends now being developed, specifically the RDBE in the U.S. and the dBBC in Europe, as well as others. The Mark 5C system is being planned for use with the VLBI2010 system and will also be used by NRAO as part of the VLBA sensitivity upgrade program; it will also be available to the global VLBI community from Conduant. Mark 5C system specification and development is supported by Haystack Observatory, NRAO, and Conduant Corporation. Prototype Mark 5C systems are expected in early 2010.
In this paper we propose an innovative learning algorithm - a variation of One-class nu Support Vector Machines (SVMs) learning algorithm to produce sparser solutions with much reduced computational complexities. The proposed technique returns an approximate solution, nearly as good as the solution set obtained by the classical approach, by minimizing the original risk function along with a regularization term. We introduce a bi-criterion optimization that helps guide the search towards the optimal set in much reduced time. The outcome of the proposed learning technique was compared with the benchmark one-class Support Vector machines algorithm which more often leads to solutions with redundant support vectors. Through out the analysis, the problem size for both optimization routines was kept consistent. We have tested the proposed algorithm on a variety of data sources under different conditions to demonstrate the effectiveness. In all cases the proposed algorithm closely preserves the accuracy of standard one-class nu SVMs while reducing both training time and test time by several factors.
The Baseline Report captures range and spaceport capabilities at five sites: KSC, CCAFS, VAFB, Wallops, and Kodiak. The Baseline depicts a future state that relies on existing technology, planned upgrades, and straight-line recapitalization at these sites projected through 2030. The report presents an inventory of current spaceport and range capabilities at these five sites. The baseline is the first part of analyzing a business case for a set of capabilities designed to transform U.S. ground and space launch operations toward a single, integrated national "system" of space transportation systems. The second part of the business case compares current capabilities with technologies needed to support the integrated national "system". The final part, a return on investment analysis, identifies the technologies that best lead to the integrated national system and reduce recurring costs..Numerous data sources were used to define and describe the baseline spaceport and range by identifying major systems and elements and describing capabilities, limitations, and capabilities
TIGRAS 2.0 is a computer program designed to satisfy a need for improved means for analyzing the tracking demands of interplanetary space-flight missions upon the set of ground antenna resources of the Deep Space Network (DSN) and for allocating those resources. Written in Microsoft Visual C++, TIGRAS 2.0 provides a single rich graphical analysis environment for use by diverse DSN personnel, by connecting to various data sources (relational databases or files) based on the stages of the analyses being performed. Notable among the algorithms implemented by TIGRAS 2.0 are a DSN antenna-load-forecasting algorithm and a conflict-aware DSN schedule-generating algorithm. Computers running TIGRAS 2.0 can also be connected using SOAP/XML to a Web services server that provides analysis services via the World Wide Web. TIGRAS 2.0 supports multiple windows and multiple panes in each window for users to view and use information, all in the same environment, to eliminate repeated switching among various application programs and Web pages. TIGRAS 2.0 enables the use of multiple windows for various requirements, trajectory-based time intervals during which spacecraft are viewable, ground resources, forecasts, and schedules. Each window includes a time navigation pane, a selection pane, a graphical display pane, a list pane, and a statistics pane.
The NASA Marshall Space Flight Center introduced the Lightning Nitrogen Oxides Model (LNOM) a couple of years ago to combine routine state-of-the-art measurements of lightning with empirical laboratory results of lightning NOx production. The routine measurements included VHF lightning source data [such as from the North Alabama Lightning Mapping Array (LMA)], and ground flash location, peak current, and stroke multiplicity data from the National Lightning Detection Network(TradeMark) (NLDN). Following these initial runs of LNOM, the model was updated to include several non-return stroke lightning NOx production mechanisms, and provided the impact of lightning NOx on an August 2006 run of CMAQ. In this study, we review the evolution of the LNOM in greater detail and discuss the model?s latest upgrades and applications. Whereas previous applications were limited to five summer months of data for North Alabama thunderstorms, the most recent LNOM analyses cover several years. The latest statistics of ground and cloud flash NOx production are provided.
NASA:s hyperwall is a sophisticated visualization tool used to display large datasets. The hyperwall, or video wall, is capable of displaying multiple high-definition data visualizations and/or images simultaneously across an arrangement of screens. Functioning as a key component at many NASA exhibits, the hyperwall is used to help explain phenomena, ideas, or examples of world change. The traveling version of the hyperwall is typically comprised of nine 42-50" flat-screen monitors arranged in a 3x3 array (as depicted below). However, it is not limited to monitor size or number; screen sizes can be as large as 52" and the arrangement of screens can include more than nine monitors. Generally, NASA satellite and model data are used to highlight particular themes in atmospheric, land, and ocean science. Many of the existing hyperwall stories reveal change across space and time, while others display large-scale still-images accompanied by descriptive, story-telling captions. Hyperwall content on a variety of Earth Science topics already exists and is made available to the public at: eospso.gsfc.nasa.gov/hyperwall. Keynote and PowerPoint presentations as well as Summary of Story files are available for download on each existing topic. New hyperwall content and accompanying files will continue being developed to promote scientific literacy across a diverse group of audience members. NASA invites the use of content accessible through this website but requests the user to acknowledge any and all data sources referenced in the content being used.
A brief review is presented on the state-of-the-art in rotorcraft engine health monitoring technologies including summaries on current practices in the area of sensors, data acquisition, monitoring and analysis. Also, presented are guidelines for verification and validation of Health Usage Monitoring System (HUMS) and specifically for maintenance credits to extend part life. Finally, a number of new efforts in HUMS are summarized as well as lessons learned and future challenges. In particular, gaps are identified to supporting maintenance credits to extend rotorcraft engine part life. A number of data sources were consulted and include results from a survey from the HUMS community, Society of Automotive Engineers (SAE) documents, American Helicopter Society (AHS) papers, as well as references from Defence Science & Technology Organization (DSTO), Civil Aviation Authority (CAA), and Federal Aviation Administration (FAA).