Workshop proceedings: Information Systems for Space Astrophysics in the 21st Century, volume 1

The Astrophysical Information Systems Workshop was one of the three Integrated Technology Planning workshops. Its objectives were to develop an understanding of future mission requirements for information systems, the potential role of technology in meeting these requirements, and the areas in which NASA investment might have the greatest impact. Workshop participants were briefed on the astrophysical mission set with an emphasis on those missions that drive information systems technology, the existing NASA space-science operations infrastructure, and the ongoing and planned NASA information systems technology programs. Program plans and recommendations were prepared in five technical areas: Mission Planning and Operations; Space-Borne Data Processing; Space-to-Earth Communications; Science Data Systems; and Data Analysis, Integration, and Visualization

A survey of simulation techniques in commerce and defence

Despite the developments in Modelling and Simulation (M&S) tools and techniques over the past years, there has been a gap in the M&S research and practice in healthcare on developing a toolkit to assist the modellers and simulation practitioners with selecting an appropriate set of techniques. This study is a preliminary step towards this goal. This paper presents some results from a systematic literature survey on applications of M&S in the commerce and defence domains that could inspire some improvements in the healthcare. Interim results show that in the commercial sector Discrete-Event Simulation (DES) has been the most widely used technique with System Dynamics (SD) in second place. However in the defence sector, SD has gained relatively more attention. SD has been found quite useful for qualitative and soft factors analysis. From both the surveys it becomes clear that there is a growing trend towards using hybrid M&S approaches

Advancing the Standards for Unmanned Air System Communications, Navigation and Surveillance

Under NASA program NNA16BD84C, new architectures were identified and developed for supporting reliable and secure Communications, Navigation and Surveillance (CNS) needs for Unmanned Air Systems (UAS) operating in both controlled and uncontrolled airspace. An analysis of architectures for the two categories of airspace and an implementation technology readiness analysis were performed. These studies produced NASA reports that have been made available in the public domain and have been briefed in previous conferences. We now consider how the products of the study are influencing emerging directions in the aviation standards communities. The International Civil Aviation Organization (ICAO) Communications Panel (CP), Working Group I (WG-I) is currently developing a communications network architecture known as the Aeronautical Telecommunications Network with Internet Protocol Services (ATN/IPS). The target use case for this service is secure and reliable Air Traffic Management (ATM) for manned aircraft operating in controlled airspace. However, the work is more and more also considering the emerging class of airspace users known as Remotely Piloted Aircraft Systems (RPAS), which refers to certain UAS classes. In addition, two Special Committees (SCs) in the Radio Technical Commission for Aeronautics (RTCA) are developing Minimum Aviation System Performance Standards (MASPS) and Minimum Operational Performance Standards (MOPS) for UAS. RTCA SC-223 is investigating an Internet Protocol Suite (IPS) and AeroMACS aviation data link for interoperable (INTEROP) UAS communications. Meanwhile, RTCA SC-228 is working to develop Detect And Avoid (DAA) equipment and a Command and Control (C2) Data Link MOPS establishing LBand and C-Band solutions. These RTCA Special Committees along with ICAO CP WG/I are therefore overlapping in terms of the Communication, Navigation and Surveillance (CNS) alternatives they are seeking to provide for an integrated manned- and unmanned air traffic management service as well as remote pilot command and control. This paper presents UAS CNS architecture concepts developed under the NASA program that apply to all three of the aforementioned committees. It discusses the similarities and differences in the problem spaces under consideration in each committee, and considers the application of a common set of CNS alternatives that can be widely applied. As the works of these committees progress, it is clear that the overlap will need to be addressed to ensure a consistent and safe framework for worldwide aviation. In this study, we discuss similarities and differences in the various operational models and show how the CNS architectures developed under the NASA program apply

Survey of Federal, National, and International standards applicable to the NASA applications data services

An applications data service (ADS) was developed to meet the challenges in the data access and integration. The ADS provides a common service to locate and access applications data electronically and integrate the cross correlative data sets required by multiple users. Its catalog and network services increase data visibility as well as provide the data in a more rapid manner and a usable form

Keeping Research Data Safe 2: Final Report

The first Keeping Research Data Safe study funded by JISC made a major contribution to understanding of long-term preservation costs for research data by developing a cost model and indentifying cost variables for preserving research data in UK universities (Beagrie et al, 2008). However it was completed over a very constrained timescale of four months with little opportunity to follow up other major issues or sources of preservation cost information it identified. It noted that digital preservation costs are notoriously difficult to address in part because of the absence of good case studies and longitudinal information for digital preservation costs or cost variables. In January 2009 JISC issued an ITT for a study on the identification of long-lived digital datasets for the purposes of cost analysis. The aim of this work was to provide a larger body of material and evidence against which existing and future data preservation cost modelling exercises could be tested and validated. The proposal for the KRDS2 study was submitted in response by a consortium consisting of 4 partners involved in the original Keeping Research Data Safe study (Universities of Cambridge and Southampton, Charles Beagrie Ltd, and OCLC Research) and 4 new partners with significant data collections and interests in preservation costs (Archaeology Data Service, University of London Computer Centre, University of Oxford, and the UK Data Archive). A range of supplementary materials in support of this main report have been made available on the KRDS2 project website at http://www.beagrie.com/jisc.php. That website will be maintained and continuously updated with future work as a resource for KRDS users

Integrating ERAU’s Suborbital Space Flight Simulator - ADS Data into NextGen TestBed Simulations

The static Suborbital Space Flight Simulator (SSFS) in the Applied Aviation Sciences (AAS) department at Embry-Riddle Aeronautical University (ERAU) is working together with the Next Generation ERAU Advanced Research (NEAR) laboratory on Daytona Beach campus. The NEAR lab will support the SSFS by using an Energy Management Display Indicator (EMDI) display for rendering live ADS-B data. The data simulated at the SSFS lab will be later shared and transferred to the Next Generation Test Bed (NGTB) at Daytona International airport to be integrated into the National Air System for research and educational purposes. Furthermore, the live ADS-B data will be also used in remote locations using a Ground Based Transceiver (GBT). The SSFS will incorporate real weather scenarios that are currently being processed at the AAS department to mimic real suborbital trajectories or point-to-point (PTP) trajectories between different spaceports. Some of the spaceports to be considered for the NAS include the Midland spaceport in Texas, Spaceport America in New Mexico, Kona spaceport in Hawaii, Kodiak spaceport in Alaska and Cecile spaceport in Florida. Also, PTP trajectories will be generated between the NAS and other international spaceports within the Single European Sky Air Traffic Management Research (SESAR) program among others. Different PTP suborbital flights will allow novel data collection in the mesosphere region providing unprecedented science that will be able to use to refine current mesospheric models and further analyzed the mesosphere. Other benefits of these simulated suborbital trajectories in the SSFS will be to incorporate these trajectories (ascent and descent segments) into the NAS to further familiarize Air Traffic Controllers (ATC) with rerouted aircraft, enhance airport situational awareness, and analyze the Navigation Accuracy Category (NAC), Navigation Integrity Category (NIC) which relates the containment radius, Rc, and Source Integrity Level (SIL) which represents the percentage of exceeding the containment radius. In the U.S. NAS, ADS-B OUT can be operated as a dual link (1090 ES or 1090 MHz and UAT 978 MHz). The UAT is only used in the U.S while the 1090 ES is used internationally, such as Canada, Europe, Asia, Central America and the Pacific. The third ADS-B link is known as the Very High Frequency Data Link (VDL) Mode 4 and it is only used in the north of Europe. What key elements will need to be considered or integrated into international suborbital flights that use different links? How many ground stations will be required to obtain continuous functionality of the ADS-B data? Using different links will provide different data rates during each part of the suborbital flight. For a domestic suborbital flight, the data rate when the vehicle is going through the NAS of the ascent trajectory is the same as the data rate when it is descending through the NAS. For a suborbital flight that may depart from a spaceport in the U.S. and arrive to another spaceport in Europe, the data rate during ascent and the data rate during descent may not be the same and the suborbital trajectory will require further assessment from the space operations point of view. Some of these operations include communications with aircraft during the ascent suborbital trajectory, acceleration management of the trajectory, trajectory course corrections to pin-point at the right noctilucent (NLC) layer, maximizing the science during the short time in the weightlessness environment, re-entry concerns, and energy dissipation management and communications with the NAS during the descent trajectory

Black brane entropy and hydrodynamics: the boost-invariant case

The framework of slowly evolving horizons is generalized to the case of black branes in asymptotically anti-de Sitter spaces in arbitrary dimensions. The results are used to analyze the behavior of both event and apparent horizons in the gravity dual to boost-invariant flow. These considerations are motivated by the fact that at second order in the gradient expansion the hydrodynamic entropy current in the dual Yang-Mills theory appears to contain an ambiguity. This ambiguity, in the case of boost-invariant flow, is linked with a similar freedom on the gravity side. This leads to a phenomenological definition of the entropy of black branes. Some insights on fluid/gravity duality and the definition of entropy in a time-dependent setting are elucidated.Comment: RevTeX, 42 pages, 4 figure

Office of Space Terrestrial Applications (OSTA)/Applications Data Service (ADS) data systems standards

Standards needed to interconnect applications data service pilots for data sharing were identified. Current pilot methodologies are assessed. Recommendations for future work are made. A preliminary set of requirements for guidelines and standards for catalogues, directories, and dictionaries was identified. The user was considered to be a scientist at a terminal. Existing and emerging national and international telecommunication standards were adopted where possible in view of new and unproven standards