Potential Market for Satellite Technology in Meeting Telecommunication Needs of Developing Nations

NASA Technical Reports Server (NTRS)

1996-01-01

A recent study examined the potential for satellite technology to meet the telecommunication needs of developing nations. The growth of these nations depends on their attracting and holding the industrial investments of developed nations. This will not be likely with the antiquated telecommunications infrastructure typical of developing nations. On the contrary, it will require an infrastructure that is compatible with international standards. Most of the developing nations perceive this necessity and are pursuing the necessary upgrades. The rate of replacement, types of technology, services affected, and the terrestrial/satellite mix differ by each nation's priorities and gross national product (GNP).

Fault displacement hazard assessment for nuclear installations based on IAEA safety standards

NASA Astrophysics Data System (ADS)

Fukushima, Y.

2016-12-01

In the IAEA Safety NS-R-3, surface fault displacement hazard assessment (FDHA) is required for the siting of nuclear installations. If any capable faults exist in the candidate site, IAEA recommends the consideration of alternative sites. However, due to the progress in palaeoseismological investigations, capable faults may be found in existing site. In such a case, IAEA recommends to evaluate the safety using probabilistic FDHA (PFDHA), which is an empirical approach based on still quite limited database. Therefore a basic and crucial improvement is to increase the database. In 2015, IAEA produced a TecDoc-1767 on Palaeoseismology as a reference for the identification of capable faults. Another IAEA Safety Report 85 on ground motion simulation based on fault rupture modelling provides an annex introducing recent PFDHAs and fault displacement simulation methodologies. The IAEA expanded the project of FDHA for the probabilistic approach and the physics based fault rupture modelling. The first approach needs a refinement of the empirical methods by building a world wide database, and the second approach needs to shift from kinematic to the dynamic scheme. Both approaches can complement each other, since simulated displacement can fill the gap of a sparse database and geological observations can be useful to calibrate the simulations. The IAEA already supported a workshop in October 2015 to discuss the existing databases with the aim of creating a common worldwide database. A consensus of a unified database was reached. The next milestone is to fill the database with as many fault rupture data sets as possible. Another IAEA work group had a WS in November 2015 to discuss the state-of-the-art PFDHA as well as simulation methodologies. Two groups jointed a consultancy meeting in February 2016, shared information, identified issues, discussed goals and outputs, and scheduled future meetings. Now we may aim at coordinating activities for the whole FDHA tasks jointly.

IAEA activities on atomic, molecular and plasma-material interaction data for fusion

NASA Astrophysics Data System (ADS)

Braams, Bastiaan J.; Chung, Hyun-Kyung

2013-09-01

The IAEA Atomic and Molecular Data Unit (http://www-amdis.iaea.org/) aims to provide internationally evaluated and recommended data for atomic, molecular and plasma-material interaction (A+M+PMI) processes in fusion research. The Unit organizes technical meetings and coordinates an A+M Data Centre Network (DCN) and a Code Centre Network (CCN). In addition the Unit organizes Coordinated Research Projects (CRPs), for which the objectives are mixed between development of new data and evaluation and recommendation of existing data. In the area of A+M data we are placing new emphasis in our meeting schedule on data evaluation and especially on uncertainties in calculated cross section data and the propagation of uncertainties through structure data and fundamental cross sections to effective rate coefficients. Following a recent meeting of the CCN it is intended to use electron scattering on Be, Ne and N2 as exemplars for study of uncertainties and uncertainty propagation in calculated data; this will be discussed further at the presentation. Please see http://www-amdis.iaea.org/CRP/ for more on our active and planned CRPs, which are concerned with atomic processes in core and edge plasma and with plasma interaction with beryllium-based surfaces and with irradiated tungsten.

Special issue containing papers presented at the 12th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems (7-11 September 2011) Special issue containing papers presented at the 12th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems (7-11 September 2011)

NASA Astrophysics Data System (ADS)

Berk, H. L.

2012-09-01

The topic of the behaviour of energetic alpha particles in magnetic fusion confined plasmas is perhaps the ultimate frontier plasma physics issue that needs to be understood in the quest to achieve controlled power from the fusion reaction in magnetically confined plasmas. The partial pressure of alpha particles in a burning plasma will be ~5-10% of the total pressure and under these conditions the alpha particles may be prone to develop instability through Alfvénic interaction. This may lead, even with moderate alpha particle loss, to a burn quench or severe wall damage. Alternatively, benign Alfvénic signals may allow the vital information to control a fusion burn. The significance of this issue has led to extensive international investigations and a biannual meeting that began in Kyiv in 1989, followed by subsequent meetings in Aspenäs (1991), Trieste (1993), Princeton (1995), JET/Abingdon (1997), Naka (1999), Gothenburg (2001), San Diego (2003), Takayama (2005), Kloster Seeon (2007) and Kyiv (2009). The meeting was initially entitled 'Alpha Particles in Fusion Research' and then was changed during the 1997 meeting to 'Energetic Particles in Magnetic Confinement Systems' in appreciation of the need to study the significance of the electron runaway, which can lead to the production of energetic electrons with energies that can even exceed the energy produced by fusion products. This special issue presents some of the mature interesting work that was reported at the 12th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems, which was held in Austin, Texas, USA (7-11 September 2011). This meeting immediately followed a related meeting, the 5th IAEA Technical Meeting on Theory of Plasma Wave Instabilities (5-7 September 2011). The meetings shared one day (7 September 2011) with presentations relevant to both groups. The presentations from most of the participants, as well as some preliminary versions of papers, are available at the

USSP-IAEA WORKSHOP ON ADVANCED SENSORS FOR SAFEGUARDS.

DOE Office of Scientific and Technical Information (OSTI.GOV)

PEPPER,S.; QUEIROLO, A.; ZENDEL, M.

2007-11-13

The IAEA Medium Term Strategy (2006-2011) defines a number of specific goals in respect to the IAEA's ability to provide assurances to the international community regarding the peaceful use of nuclear energy through States adherences to their respective non-proliferation treaty commitments. The IAEA has long used and still needs the best possible sensors to detect and measure nuclear material. The Department of Safeguards, recognizing the importance of safeguards-oriented R&D, especially targeting improved detection capabilities for undeclared facilities, materials and activities, initiated a number of activities in early 2005. The initiatives included letters to Member State Support Programs (MSSPs), personal contactsmore » with known technology holders, topical meetings, consultant reviews of safeguards technology, and special workshops to identify new and novel technologies and methodologies. In support of this objective, the United States Support Program to IAEA Safeguards hosted a workshop on ''Advanced Sensors for Safeguards'' in Santa Fe, New Mexico, from April 23-27, 2007. The Organizational Analysis Corporation, a U.S.-based management consulting firm, organized and facilitated the workshop. The workshop's goal was to help the IAEA identify and plan for new sensors for safeguards implementation. The workshop, which was attended by representatives of seven member states and international organizations, included presentations by technology holders and developers on new technologies thought to have relevance to international safeguards, but not yet in use by the IAEA. The presentations were followed by facilitated breakout sessions where the participants considered two scenarios typical of what IAEA inspectors might face in the field. One scenario focused on an enrichment plant; the other scenario focused on a research reactor. The participants brainstormed using the technologies presented by the participants and other technologies known to them to propose

Proceedings of the Twenty-First NASA Propagation Experimenters Meeting (NAPEX XXI) and the Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop

NASA Technical Reports Server (NTRS)

Golshan, Nasser (Editor)

1997-01-01

The NASA Propagation Experimenters (NAPEX) meeting is convened each year to discuss studies supported by the NASA Propagation Program. Representatives from the satellite communications industry, academia and government who have an interest in space-ground radio wave propagation are invited to NAPEX meetings for discussions and exchange of information. The reports delivered at this meeting by program managers and investigators present recent activities and future plans. This forum provides an opportunity for peer discussion of work in progress, timely dissemination of propagation results, and close interaction with the satellite communications industry.

Proceedings of the Joint IAEA/CSNI Specialists` Meeting on Fracture Mechanics Verification by Large-Scale Testing held at Pollard Auditorium, Oak Ridge, Tennessee

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pugh, C.E.; Bass, B.R.; Keeney, J.A.

This report contains 40 papers that were presented at the Joint IAEA/CSNI Specialists` Meeting Fracture Mechanics Verification by Large-Scale Testing held at the Pollard Auditorium, Oak Ridge, Tennessee, during the week of October 26--29, 1992. The papers are printed in the order of their presentation in each session and describe recent large-scale fracture (brittle and/or ductile) experiments, analyses of these experiments, and comparisons between predictions and experimental results. The goal of the meeting was to allow international experts to examine the fracture behavior of various materials and structures under conditions relevant to nuclear reactor components and operating environments. The emphasismore » was on the ability of various fracture models and analysis methods to predict the wide range of experimental data now available. The individual papers have been cataloged separately.« less

IAEA activities in the area of partitioning and transmutation

NASA Astrophysics Data System (ADS)

Stanculescu, Alexander

2006-06-01

Four major challenges are facing the long-term development of nuclear energy: improvement of the economic competitiveness, meeting increasingly stringent safety requirements, adhering to the criteria of sustainable development, and public acceptance. Meeting the sustainability criteria is the driving force behind the topic of this paper. In this context, sustainability has two aspects: natural resources and waste management. IAEA's activities in the area of Partitioning and Transmutation (P&T) are mostly in response to the latter. While not involving the large quantities of gaseous products and toxic solid wastes associated with fossil fuels, radioactive waste disposal is today's dominant public acceptance issue. In fact, small waste quantities permit a rigorous confinement strategy, and mined geological disposal is the strategy followed by some countries. Nevertheless, political opposition arguing that this does not yet constitute a safe disposal technology has largely stalled these efforts. One of the primary reasons cited is the long life of many of the radioisotopes generated from fission. This concern has led to increased R&D efforts to develop a technology aimed at reducing the amount and radio-toxicity of long-lived radioactive waste through transmutation in fission reactors or sub-critical systems. In the frame of the Project on Technology Advances in Fast Reactors and Accelerator-Driven Systems (ADS), the IAEA initiated a number of activities on utilization of plutonium and transmutation of long-lived radioactive waste, ADS, and deuterium-tritium plasma-driven sub-critical systems. The paper presents past accomplishments, current status and planned activities of this IAEA project.

Meeting Report: Long Term Monitoring of Global Vegetation using Moderate Resolution Satellites

NASA Technical Reports Server (NTRS)

Morisette, Jeffrey; Heinsch, Fath Ann; Running, Steven W.

2006-01-01

The international community has long recognized the need to coordinate observations of Earth from space. In 1984, this situation provided the impetus for creating the Committee on Earth Observation Satellites (CEOS), an international coordinating mechanism charged with coordinating international civil spaceborne missions designed to observe and study planet Earth. Within CEOS, its Working Group on Calibration and Validation (WGCV) is tasked with coordinating satellite-based global observations of vegetation. Currently, several international organizations are focusing on the requirements for Earth observation from space to address key science questions and societal benefits related to our terrestrial environment. The Global Vegetation Workshop, sponsored by the WGCV and held in Missoula, Montana, 7-10 August, 2006, was organized to establish a framework to understand the inter-relationships among multiple, global vegetation products and identify opportunities for: 1) Increasing knowledge through combined products, 2) Realizing efficiency by avoiding redundancy, and 3) Developing near- and long-term plans to avoid gaps in our understanding of critical global vegetation information. The Global Vegetation Workshop brought together 135 researchers from 25 states and 14 countries to advance these themes and formulate recommendations for CEOS members and the Global Earth Observation System of Systems (GEOSS). The eighteen oral presentations and most of the 74 posters presented at the meeting can be downloaded from the meeting website (www.ntsg.umt.edu/VEGMTG/). Meeting attendees were given a copy of the July 2006 IEEE Transactions on Geoscience and Remote Sensing Special Issue on Global Land Product Validation, coordinated by the CEOS Working Group on Calibration and Validation (WGCV). This issue contains 29 articles focusing on validation products from several of the sensors discussed during the workshop.

PREFACE: 11th IAEA Technical Meeting on H-mode Physics and Transport Barriers

NASA Astrophysics Data System (ADS)

Takizuka, Tomonori

2008-07-01

This volume of Journal of Physics: Conference Series contains papers based on invited talks and contributed posters presented at the 11th IAEA Technical Meeting on H-mode Physics and Transport Barriers. This meeting was held at the Tsukuba International Congress Center in Tsukuba, Japan, on 26-28 September 2007, and was organized jointly by the Japan Atomic Energy Agency and the University of Tsukuba. The previous ten meetings in this series were held in San Diego (USA) 1987, Gut Ising (Germany) 1989, Abingdon (UK) 1991, Naka (Japan) 1993, Princeton (USA) 1995, Kloster Seeon (Germany) 1997, Oxford (UK) 1999, Toki (Japan) 2001, San Diego (USA) 2003, and St Petersburg (Russia) 2005. The purpose of the eleventh meeting was to present and discuss new results on H-mode (edge transport barrier, ETB) and internal transport barrier, ITB, experiments, theory and modeling in magnetic fusion research. It was expected that contributions give new and improved insights into the physics mechanisms behind high confinement modes of H-mode and ITBs. Ultimately, this research should lead to improved projections for ITER. As has been the tradition at the recent meetings of this series, the program was subdivided into six topics. The topics selected for the eleventh meeting were: H-mode transition and the pedestal-width Dynamics in ETB: ELM threshold, non-linear evolution and suppression, etc Transport relations of various quantities including turbulence in plasmas with ITB: rotation physics is especially highlighted Transport barriers in non-axisymmetric magnetic fields Theory and simulation on transport barriers Projections of transport barrier physics to ITER For each topic there was an invited talk presenting an overview of the topic, based on contributions to the meeting and on recently published external results. The six invited talks were: A Leonard (GA, USA): Progress in characterization of the H-mode pedestal and L-H transition N Oyama (JAEA, Japan): Progress and issues in

Proceedings of the Fourteenth NASA Propagation Experimenters Meeting (NAPEX 14) and the Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop

NASA Technical Reports Server (NTRS)

Davarian, Faramaz (Editor)

1990-01-01

The NASA Propagation Experimenters Meeting (NAPEX), supported by the NASA Propagation Program, is convened annually to discuss studies made on radio wave propagation by investigators from domestic and international organizations. NAPEX XIV was held on May 11, 1990, at the Balcones Research Centers, University of Texas, Austin, Texas. The meeting was organized into two technical sessions: Satellite (ACTS) and the Olympus Spacecraft, while the second focused on the fixed and mobile satellite propagation studies and experiments. Following NAPEX XIV, the ACTS Miniworkshop was held at the Hotel Driskill, Austin, Texas, on May 12, 1990, to review ACTS propagation activities since the First ACTS Propagation Studies Workshop was held in Santa Monica, California, on November 28 and 29, 1989.

Meeting the challenges of global nuclear medicine technologist training in the 21st century: the IAEA Distance Assisted Training (DAT) program.

PubMed

Patterson, Heather E; Nunez, Margarita; Philotheou, Geraldine M; Hutton, Brian F

2013-05-01

Many countries have made significant investments in nuclear medicine (NM) technology with the acquisition of modern equipment and establishment of facilities, however, often appropriate training is not considered as part of these investments. Training for NM professionals is continually evolving, with a need to meet changing requirements in the workforce. Even places where established higher education courses are available, these do not necessarily cater to the practical component of training and the ever-changing technology that is central to medical imaging. The continuing advances in NM technology and growth of applications in quantitative clinical assessment place increases the pressure on technologists to learn and practice new techniques. Not only is training to understand new concepts limited but often there is inadequate training in the basics of NM and this can be a major constraint to the effective use of the evolving technology. Developing appropriate training programs for the broader international NM community is one of the goals of the International Atomic Energy Agency (IAEA). A particularly successful and relevant development has been the program on 'distance assisted training (DAT) for NM professionals'. The development of DAT was initiated in the 1990s through Australian Government funding, administered under auspices of the IAEA through its Regional Cooperative Agreement, involving most countries in Asia that are Member States of the IAEA. The project has resulted in the development of a set of training modules which are designed for use under direct supervision in the workplace, delivered through means of distance-learning. The program has undergone several revisions and peer reviews with the current version providing a comprehensive training package that is now available online. DAT has been utilized widely in Asia or the Pacific region, Latin America, and parts of Africa and Europe. Currently there are approximately 1000 registered participants

Sessions and Abstracts by Day for Satellite Meeting: Comparative Physiology of Respiration with Emphasis on Avian Respiratory Control, October 11 and 12, 1981.

ERIC Educational Resources Information Center

Physiologist, 1981

1981-01-01

Provides abstracts of contributed and invited papers presented at a satellite meeting on "Comparative Physiology of Respiration," October 11 and 12, 1981, at Ohio State University, as part of the 32nd Annual Fall Meeting of the American Physiological Society. (CS)

Ready To Read: Laying the Foundation for School Success. Satellite Town Meeting #77 (March 20, 2001). [Videotape].

ERIC Educational Resources Information Center

Department of Education, Washington, DC.

This videotape (in either VHS of 3/4 inch format) presents an interactive teleconference where renowned national experts, local educators, and community leaders share ideas on how to improve schools and reach the National Educational Goals. This 60-minute Satellite Town Meeting focuses on laying the foundation for school success through readiness…

Proceedings of the Twentieth NASA Propagation Experimenters Meeting (NAPEX 20) and the Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop

NASA Technical Reports Server (NTRS)

Golshan, Nasser (Editor)

1996-01-01

The NASA Propagation Experimenters (NAPEX) Meeting is convened each year to discuss studies supported by the NASA Propagation Program. Representatives from the satellite communications (satcom) industry, academia, and government who have an interest in space-ground radio wave propagation are invited to NAPEX meetings for discussions and exchange of information. The reports delivered at these meetings by program managers and investigators present recent activities and future plans. This forum provides an opportunity for peer discussion of work in progress, timely dissemination of propagation results, and close interaction with the satcom industry.

Proceedings of the 19th NASA Propagation Experimenters Meeting (NAPEX 19) and the 7th Advanced Communications Technology Satellite (ACTS) Propagation Studies Workshop (APSW 7)

NASA Technical Reports Server (NTRS)

Davarian, Faramaz (Editor)

1995-01-01

The NASA Propagation Experimenters Meeting (NAPEX), supported by the NASA Propagation Program, is convened annually to discuss studies made on radio wave propagation by investigators from domestic and international organizations. NAPEX 19 was held on 14 Jun. 1995, in Fort Collins, Colorado. Participants included representatives from Canada, Japan, and the United States, including researchers from universities, government agencies, and private industry. The meeting focused on mobile personal satellite systems and the use of 20/30-GHz band for fixed and mobile satellite applications. In total, 18 technical papers were presented. Following NAPEX 19, the Advanced Communications Technology Satellite (ACTS) Propagation Studies Workshop 7 (APSW 7) was held on 15-16 Jun. 1995, to review ACTS propagation activities with emphasis on the experimenters' status reports and dissemination of propagation data to industry.

The US Support Program to IAEA Safeguards Priority of Training and Human Resources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Queirolo,A.

2008-06-13

The U.S. Support Program to IAEA Safeguards (USSP) priority of training and human resources is aimed at providing the Department of Safeguards with an appropriate mixture of regular staff and extrabudgetary experts who are qualified to meet the IAEA's technical needs and to provide personnel with appropriate instruction to improve the technical basis and specific skills needed to perform their job functions. The equipment and methods used in inspection activities are unique, complex, and evolving. New and experienced safeguards inspectors need timely and effective training to perform required tasks and to learn new skills prescribed by new safeguards policies ormore » agreements. The role of the inspector has changed from that of strictly an accountant to include that of a detective. New safeguards procedures are being instituted, and therefore, experienced inspectors must be educated on these new procedures. The USSP also recognizes the need for training safeguards support staff, particularly those who maintain and service safeguards equipment (SGTS), and those who perform information collection and analysis (SGIM). The USSP is committed to supporting the IAEA with training to ensure the effectiveness of all staff members and will continue to offer its assistance in the development and delivery of basic, refresher, and advanced training courses. This paper will discuss the USSP ongoing support in the area of training and IAEA staffing.« less

EDITORIAL: Special issue containing papers presented at the 11th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems Special issue containing papers presented at the 11th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems

NASA Astrophysics Data System (ADS)

Kolesnichenko, Ya.

2010-08-01

The history of fusion research resembles the way in which one builds skyscrapers: laying the first foundation stone, one thinks about the top of the skyscraper. At the early stages of fusion, when it became clear that the thermonuclear reactor would operate with DT plasma confined by the magnetic field, the study of the `top item'—the physics of 3.5 MeV alpha particles produced by the DT fusion reaction—was initiated. The first publications on this topic appeared as long ago as the 1960s. At that time, because the physics of alpha particles was far from the experimental demand, investigations were carried out by small groups of theoreticians who hoped to discover important and interesting phenomena in this new research area. Soon after the beginning of the work, theoreticians discovered that alpha particles could excite various instabilities in fusion plasmas. In particular, at the end of the 1960s an Alfvén instability driven by alpha particles was predicted. Later it turned out that a variety of Alfvén instabilities with very different features does exist. Instabilities with perturbations of the Alfvénic type play an important role in current experiments; it is likely that they will affect plasma performance in ITER and future reactors. The first experimental manifestation of instabilities excited by superthermal particles in fusion devices was observed in the PDX tokamak in 1983. In this device a large-scale instability—the so called `fishbone instability'—associated with ions produced by the neutral beam injection resulted in a loss of a large fraction of the injected energy. Since then, the study of energetic-ion-driven instabilities and the effects produced by energetic ions in fusion plasmas has attracted the growing attention of both experimentalists and theorists. Recognizing the importance of this topic, the first conference on fusion alpha particles was held in 1989 in Kyiv under the auspices of the IAEA. The meeting in Kyiv and several

Progress and status of the IAEA coordinated research project: production of Mo-99 using LEU fission or neutron activation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goldman, Ira N.; Adelfang, Pablo; Ramamoorthy, Natesan

2008-07-15

Since late 2004, the IAEA has developed and implemented a Coordinated Research Project (CRP) to assist countries interested in initiating indigenous, small-scale production of Mo-99 to meet local nuclear medicine requirements. The objective of the CRP is to provide interested countries with access to non-proprietary technologies and methods to produce Mo-99 using LEU foil or LEU mini-plate targets, or for the utilization of n,gamma neutron activation, e.g. through the use of gel generators. The project has made further progress since the RERTR 2006 meeting, with a Technical Workshop on Operational Aspects of Mo99 Production held 28-30 November 2006 in Viennamore » and the Second Research Coordination Meeting held in Bucharest, Romania 16-20 April 2007. The paper describes activities carried out as noted above, and as well as the provision of LEU foils to a number of participants, and the progress by a number of groups in preparing for LEU target assembly and disassembly, irradiation, chemical processing, and waste management. The participants' progress in particular on thermal hydraulics computations required for using LEU targets is notable, as also the progress in gel generator plant operations in India and Kazakhstan. Poland has joined as a new research agreement holder and an application by Egypt to be a contract holder is undergoing internal review in the IAEA and is expected to be approved. The IAEA has also participated in several open meetings of the U.S. National Academy of Sciences Study on Producing Medical Radioisotopes without HEU, which will also be discussed in the paper. (author)« less

Recommended observational skills training for IAEA safeguards inspections. Final report: Recommended observational skills training for IAEA safeguards inspections

DOE Office of Scientific and Technical Information (OSTI.GOV)

Toquam, J.L.; Morris, F.A.

This is the second of two reports prepared to assist the International Atomic Energy Agency (IAEA or Agency) in enhancing the effectiveness of its international safeguards inspections through inspector training in {open_quotes}Observational Skills{close_quotes}. The first (Phase 1) report was essentially exploratory. It defined Observational Skills broadly to include all appropriate cognitive, communications, and interpersonal techniques that have the potential to help IAEA safeguards inspectors function more effectively. It identified 10 specific Observational Skills components, analyzed their relevance to IAEA safeguards inspections, and reviewed a variety of inspection programs in the public and private sectors that provide training in one ormore » more of these components. The report concluded that while it should be possible to draw upon these other programs in developing Observational Skills training for IAEA inspectors, the approaches utilized in these programs will likely require significant adaption to support the specific job requirements, policies, and practices that define the IAEA inspector`s job. The overall objective of this second (Phase 2) report is to provide a basis for the actual design and delivery of Observational Skills training to IAEA inspectors. The more specific purposes of this report are to convey a fuller understanding of the potential application of Observational Skills to the inspector`s job, describe inspector perspectives on the relevance and importance of particular Observational Skills, identify the specific Observational Skill components that are most important and relevant to enhancing safeguards inspections, and make recommendations as to Observational Skills training for the IAEA`s consideration in further developing its Safeguards training program.« less

Advanced communications satellites

NASA Technical Reports Server (NTRS)

Sivo, J. N.

1980-01-01

The increase in demand for satellite communications services brought about shortages in available transponder capacity, especially at C-band. Interest shifted to the Ku-band frequency and currently carriers are rapidly moving to secure orbital slots for future satellite development. Projections of communications service demands over the next decade indiate growth in voice, data, and video services such that saturation of both C-band and Ku-band will occur by 1990. Emphasis must and will shift to Ka-band (20/30 GHz) frequency for fixed-satellite service. Advanced technologies such as multibeam antennas coupled with on-board satellite switching to allow implementation in this band of very high capacity satellite systems will be applied to meet the demand. Satellite system concepts that are likely in the 1990's and are likely to bring a new dimension to satellite delivered communication service are presented. The NASA 30/20 GHz communications satellite system demonstration program is discussed with emphasis on the related technology development.

Proceedings of the Twenty-First NASA Propagation Experiments Meeting (NAPEX XXI) and the Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop

NASA Technical Reports Server (NTRS)

Golshan, Nasser (Editor)

1997-01-01

The NASA Propagation Experimenters (NAPEX) meeting is convened each year to discuss studies supported by the NASA Propagation Program. Representatives from the satellite communications industry, academia and government who have an interest in space-ground radio wave propagation are invited to NAPEX meetings for discussions and exchange of information. The reports delivered at this meeting by program managers and investigators present recent activities and future plans. This forum provides an opportunity for peer discussion of work in progress, timely dissemination of propagation results, and close interaction with the satellite communications industry. NAPEX XXI took place in El Segundo, California on June 11-12, 1997 and consisted of three sessions. Session 1, entitled "ACTS Propagation Study Results & Outcome " covered the results of 20 station-years of Ka-band radio-wave propagation experiments. Session 11, 'Ka-band Propagation Studies and Models,' provided the latest developments in modeling, and analysis of experimental results about radio wave propagation phenomena for design of Ka-band satellite communications systems. Session 111, 'Propagation Research Topics,' covered a diverse range of propagation topics of interest to the space community, including overviews of handbooks and databases on radio wave propagation. The ACTS Propagation Studies miniworkshop was held on June 13, 1997 and consisted of a technical session in the morning and a plenary session in the afternoon. The morning session covered updates on the status of the ACTS Project & Propagation Program, engineering support for ACTS Propagation Terminals, and the Data Center. The plenary session made specific recommendations for the future direction of the program.

Ready To Read: Laying the Foundation for School Success. Satellite Town Meeting #77: March 20, 2001. Spanish Language Version. [Videotape].

ERIC Educational Resources Information Center

Department of Education, Washington, DC.

This interactive teleconference (in VHS format, Spanish language version) presents renowned national experts, local educators, and community leaders who share ideas on how to improve schools and reach the National Educational Goals. The 60-minute Satellite Town Meeting focuses on laying the foundation for school success through readiness to read.…

Satellite networks for education

NASA Technical Reports Server (NTRS)

Singh, J. P.; Morgan, R. P.; Rosenbaum, F. J.

1972-01-01

Satellite based educational networking is discussed with particular attention given to the potential uses of communications satellites to help meet educational needs in the United states. Four major subject areas were covered; (1) characteristics and structure of networks, (2) definition of pressures within educational establishment that provide motivation for various types of networks, (3) examination of current educational networking status for educational radio and television, instructional television fixed services, inter- and intra-state educational communication networks, computer networks, and cable television for education, and (4) identification of possible satellite based educational telecommunication services and three alternatives for implementing educational satellite systems.

PREFACE: 15th Latin American Workshop on Plasma Physics (LAWPP 2014) and 21st IAEA TM on Research Using Small Fusion Devices (RUSFD)

NASA Astrophysics Data System (ADS)

Iván Vargas-Blanco, V.; Herrera-Velázquez, J. Julio E.

2015-03-01

Written contributions from participants of the Joint 15th Latin American Workshop on Plasma Physics (LAWPP 2014) - 21st IAEA Technical Meeting on Research Using Small Fusion Devices (21st IAEA TM RUSFD). The International Advisory Committees of the 15th Latin American Workshop on Plasma Physics (LAWPP 2014) and the 21st IAEA TM on Research Using Small Fusion Devices (RUSFD), agreed to carry out together this Joint LAWPP 2014 - 21st RUSFD in San José, Costa Rica, on 27-31 January 2014. The Joint LAWPP 2014 - 21st RUSFD meeting, organized by the Instituto Tecnológico de Costa Rica, Universidad Nacional de Costa Rica, and Ad Astra Rocket Company in collaboration with the International Atomic Energy Agency (IAEA). The Latin American Workshop on Plasma Physics (LAWPP) is a series of events which has been held periodically since 1982, with the purpose of providing a forum in which the research of the Latin American plasma physics community can be displayed, as well as fostering collaborations among plasma scientists within the region and with researchers from the rest of the world. Recognized plasma scientists from developed countries are specially invited to the meeting to present the state of the art on several "hot" topics related to plasma physics. It is an open meeting, with an International Advisory Committee, in which the working language is English. It was firstly held in 1982 in Cambuquira, Brazil, followed by workshops in Medellín, Colombia (1985), Santiago de Chile, Chile (1988), Buenos Aires, Argentina (1990), Mexico City, Mexico (1992), Foz do Iguaçu, Brazil (1994, combined with the International Congress on Plasma Physics (ICPP)), Caracas, Venezuela (1997), Tandil, Argentina (1998), La Serena, Chile (2000), Sao Pedro, Brazil (2003), Mexico City, Mexico (2005), Caracas, Venezuela (2007), Santiago de Chile, Chile (2010, combined with the ICPP) and Mar de Plata, Argentina (2011). The 21st IAEA TM on Research Using Small Fusion Devices is an ideal forum for

Rapid development of tissue bank achieved by International Atomic Energy Agency (IAEA) Tissue Banking Programme in China.

PubMed

Zhang, Yu-Min; Wang, Jian-Ru; Zhang, Nai-Li; Liu, Xiao-Ming; Zhou, Mo; Ma, Shao-Ying; Yang, Ting; Li, Bao-Xing

2014-09-01

Before 1986, the development of tissue banking in China has been slow and relatively uncoordinated. Under the support of International Atomic Energy Agency (IAEA), Tissue Banking in China experienced rapid development. In this period, China Institute for Radiation Protection tissue bank mastered systematic and modern tissue banking technique by IAEA training course and gradually developed the first regional tissue bank (Shanxi Provincial Tissue Bank, SPTB) to provide tissue allograft. Benefit from training course, SPTB promoted the development of tissue transplantation by ways of training, brochure, advertisement and meeting. Tissue allograft transplantation acquired recognition from clinic and supervision and administration from government. Quality system gradually is developing and perfecting. Tissue allograft transplantation and tissue bank are developing rapidly and healthy.

Proceedings of the Seventeenth NASA Propagation Experimenters Meeting (NAPEX 17) and the Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop

NASA Technical Reports Server (NTRS)

Davarian, Faramaz (Editor)

1993-01-01

The NASA Propagation Experimenters Meeting (NAPEX) is convened annually to discuss studies made on radio wave propagation by investors from domestic and international organizations. NAPEX 17 was held on 15 June 1993. The meeting was organized into two technical sessions. The first session was dedicated to slant path propagation studies and experiments. The second session focused on propagation studies for mobile and personal communications. Preceding NAPEX 17, the Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop was held on 14 June 1993 to review ACTS propagation activities with emphasis on ACTS experiments status and data collection, processing, and exchange.

78 FR 49514 - Sunshine Act Meeting; Open Commission Meeting; Friday, August 9, 2013

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-14

... FEDERAL COMMUNICATIONS COMMISSION Sunshine Act Meeting; Open Commission Meeting; Friday, August 9, 2013 August 2, 2013. The Federal Communications Commission will hold an Open Meeting on the subjects... satellite services to the public. 2 OFFICE OF ENGINEERING & TITLE: Revision of Part 15 of the Commission's...

10 CFR 75.7 - Notification of IAEA safeguards.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 2 2011-01-01 2011-01-01 false Notification of IAEA safeguards. 75.7 Section 75.7 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) SAFEGUARDS ON NUCLEAR MATERIAL-IMPLEMENTATION OF US/IAEA AGREEMENT General Provisions § 75.7 Notification of IAEA safeguards. (a) The licensee must inform the NRC...

10 CFR 75.7 - Notification of IAEA safeguards.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Notification of IAEA safeguards. 75.7 Section 75.7 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) SAFEGUARDS ON NUCLEAR MATERIAL-IMPLEMENTATION OF US/IAEA AGREEMENT General Provisions § 75.7 Notification of IAEA safeguards. (a) The licensee must inform the NRC...

Improving the Transparency of IAEA Safeguards Reporting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Toomey, Christopher; Hayman, Aaron M.; Wyse, Evan T.

2011-07-17

In 2008, the Standing Advisory Group on Safeguards Implementation (SAGSI) indicated that the International Atomic Energy Agency's (IAEA) Safeguards Implementation Report (SIR) has not kept pace with the evolution of safeguards and provided the IAEA with a set of recommendations for improvement. The SIR is the primary mechanism for providing an overview of safeguards implementation in a given year and reporting on the annual safeguards findings and conclusions drawn by the Secretariat. As the IAEA transitions to State-level safeguards approaches, SIR reporting must adapt to reflect these evolutionary changes. This evolved report will better reflect the IAEA's transition to amore » more qualitative and information-driven approach, based upon State-as-a-whole considerations. This paper applies SAGSI's recommendations to the development of multiple models for an evolved SIR and finds that an SIR repurposed as a 'safeguards portal' could significantly enhance information delivery, clarity, and transparency. In addition, this paper finds that the 'portal concept' also appears to have value as a standardized information presentation and analysis platform for use by Country Officers, for continuity of knowledge purposes, and the IAEA Secretariat in the safeguards conclusion process. Accompanying this paper is a fully functional prototype of the 'portal' concept, built using commercial software and IAEA Annual Report data.« less

Certified reference materials for radionuclides in Bikini Atoll sediment (IAEA-410) and Pacific Ocean sediment (IAEA-412).

PubMed

Pham, M K; van Beek, P; Carvalho, F P; Chamizo, E; Degering, D; Engeler, C; Gascó, C; Gurriaran, R; Hanley, O; Harms, A V; Herrmann, J; Hult, M; Ikeuchi, Y; Ilchmann, C; Kanisch, G; Kis-Benedek, G; Kloster, M; Laubenstein, M; Llaurado, M; Mas, J L; Nakano, M; Nielsen, S P; Osvath, I; Povinec, P P; Rieth, U; Schikowski, J; Smedley, P A; Suplinska, M; Sýkora, I; Tarjan, S; Varga, B; Vasileva, E; Zalewska, T; Zhou, W

2016-03-01

The preparation and characterization of certified reference materials (CRMs) for radionuclide content in sediments collected offshore of Bikini Atoll (IAEA-410) and in the open northwest Pacific Ocean (IAEA-412) are described and the results of the certification process are presented. The certified radionuclides include: (40)K, (210)Pb ((210)Po), (226)Ra, (228)Ra, (228)Th, (232)Th, (234)U, (238)U, (239)Pu, (239+240)Pu and (241)Am for IAEA-410 and (40)K, (137)Cs, (210)Pb ((210)Po), (226)Ra, (228)Ra, (228)Th, (232)Th, (235)U, (238)U, (239)Pu, (240)Pu and (239+240)Pu for IAEA-412. The CRMs can be used for quality assurance and quality control purposes in the analysis of radionuclides in sediments, for development and validation of analytical methods and for staff training. Copyright © 2015 Elsevier Ltd. All rights reserved.

CEOS Committee on Earth Observations Satellites Consolidated Report, 1992

NASA Technical Reports Server (NTRS)

1992-01-01

A concise overview of the committee on Earth Observations Satellites (CEOS) and its Working Groups, covering the history and purpose of the Committee and its accomplishments to date are provided. The report will be updated annually before each Plenary meeting, and as developments in the Working Groups warrant. The committee on Earth Observations Satellites (originally named the International Earth Observations Satellite committee, IEOS) was treated in 1984, in response to a recommendation from the Economic Summit of Industrialized Nations Working Group on Growth, Technology, and Employment's Panel of Experts on Satellite Remote Sensing. This group recognized the multidisciplinary nature of satellite Earth observations, and the value of coordinating across all proposed missions. Thus, CEOS combined the previously existing groups for coordination on Ocean Remote-Sensing Satellites (CORSS) and coordination on Land Remote-Sensing Satellites (CLRSS), and established a broad framework for coordination across all spaceborne Earth observations missions. The first three LEOS Plenary meetings focused on treating and guiding the Working Groups deemed necessary to carry out the objectives of the CEOS members. After the third meeting, it was agreed that a more active orientation was required by the Plenary, and additional issues were brought before the group at the fourth meeting. At the fifth Plenary, international scientific programs and relevant intergovernmental organizations accepted invitations and participated as affiliate members of CEOS. This enabled progress toward integrating satellite data users' requirements into the CEOS process. Data exchange principles for global change research were also adopted. An interim CEOS Plenary meeting was held in April 1992, in preparation for the United Nations Conference on Environment and Development (UNCED). Brief encapsulations of the Plenary sessions immediately follow the Terms of Reference that govern the activities of CEOS as

Special section containing papers presented at the 13th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems (Beijing, China, 17-20 September 2013) Special section containing papers presented at the 13th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems (Beijing, China, 17-20 September 2013)

NASA Astrophysics Data System (ADS)

Lin, Z.

2014-10-01

In magnetic fusion plasmas, a significant fraction of the kinetic pressure is contributed by superthermal charged particles produced by auxiliary heating (fast ions and electrons) and fusion reactions (a-particles). Since these energetic particles are often far away from thermal equilibrium due to their non-Maxwellian distribution and steep pressure gradients, the free energy can excite electromagnetic instabilities to intensity levels well above the thermal fluctuations. The resultant electromagnetic turbulence could induce large transport of energetic particles, which could reduce heating efficiency, degrade overall plasma confinement, and damage fusion devices. Therefore, understanding and predicting energetic particle confinement properties are critical to the success of burning plasma experiments such as ITER since the ignition relies on plasma self-heating by a-particles. To promote international exchanges and collaborations on energetic particle physics, the biannual conference series under the auspices of the International Atomic Energy Agency (IAEA) were help in Kyiv (1989), Aspenas (1991), Trieste (1993), Princeton (1995), JET/Abingdon (1997), Naka (1999), Gothenburg (2001), San Diego (2003), Takayama (2005), Kloster Seeon (2007), Kyiv (2009), and Austin (2011). The papers in this special section were presented at the most recent meeting, the 13th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems, which was hosted by the Fusion Simulation Center, Peking University, Beijing, China (17-20 September 2013). The program of the meeting consisted of 71 presentations, including 13 invited talks, 26 oral contributed talks, 30 posters, and 2 summary talks, which were selected by the International Advisory Committee (IAC). The IAC members include H. Berk, L.G. Eriksson, A. Fasoli, W. Heidbrink, Ya. Kolesnichenko, Ph. Lauber, Z. Lin, R. Nazikian, S. Pinches, S. Sharapov, K. Shinohara, K. Toi, G. Vlad, and X.T. Ding. The conference program

RECRUITMENT OF U.S. CITIZENS FOR VACANCIES IN IAEA SAFEGUARDS

DOE Office of Scientific and Technical Information (OSTI.GOV)

PEPPER,S.E.; DECARO,D.; WILLIAMS,G.

The International Atomic Energy Agency (IAEA) relies on its member states to assist with recruiting qualified individuals for positions within the IAEA's secretariat. It is important that persons within and outside the US nuclear and safeguards industries become aware of career opportunities available at the IAEA, and informed about important vacancies. The IAEA has established an impressive web page to advertise opportunities for employment. However, additional effort is necessary to ensure that there is sufficient awareness in the US of these opportunities, and assistance for persons interested in taking positions at the IAEA. In 1998, the Subgroup on Safeguards Technicalmore » Support (SSTS) approved a special task under the US Support Program to IAEA Safeguards (USSP) for improving US efforts to identify qualified candidates for vacancies in IAEA's Department of Safeguards. The International Safeguards Project Office (ISPO) developed a plan that includes increased advertising, development of a web page to support US recruitment efforts, feedback from the US Mission in Vienna, and interaction with other recruitment services provided by US professional organizations. The main purpose of this effort is to educate US citizens about opportunities at the IAEA so that qualified candidates can be identified for the IAEA's consideration.« less

Technology requirements for communication satellites in the 1980's

NASA Technical Reports Server (NTRS)

Burtt, J. E.; Moe, C. R.; Elms, R. V.; Delateur, L. A.; Sedlacek, W. C.; Younger, G. G.

1973-01-01

The key technology requirements are defined for meeting the forecasted demands for communication satellite services in the 1985 to 1995 time frame. Evaluation is made of needs for services and technical and functional requirements for providing services. The future growth capabilities of the terrestrial telephone network, cable television, and satellite networks are forecasted. The impact of spacecraft technology and booster performance and costs upon communication satellite costs are analyzed. Systems analysis techniques are used to determine functional requirements and the sensitivities of technology improvements for reducing the costs of meeting requirements. Recommended development plans and funding levels are presented, as well as the possible cost saving for communications satellites in the post 1985 era.

10 CFR 75.12 - Communication of information to IAEA.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Communication of information to IAEA. 75.12 Section 75.12 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) SAFEGUARDS ON NUCLEAR MATERIAL-IMPLEMENTATION OF US/IAEA AGREEMENT Facility and Location Information § 75.12 Communication of information to IAEA. (a) Except as...

10 CFR 75.12 - Communication of information to IAEA.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 2 2011-01-01 2011-01-01 false Communication of information to IAEA. 75.12 Section 75.12 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) SAFEGUARDS ON NUCLEAR MATERIAL-IMPLEMENTATION OF US/IAEA AGREEMENT Facility and Location Information § 75.12 Communication of information to IAEA. (a) Except as...

Proceedings of the Fifteenth NASA Propagation Experimenters Meeting (NAPEX 15) and the Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop

NASA Technical Reports Server (NTRS)

Davarian, Faramaz (Editor)

1991-01-01

The NASA Propagation Experimenters Meeting (NAPEX), supported by the NASA Propagation Program, is convened annually to discuss studies made on radio wave propagation by investigators from domestic and international organizations. The meeting was organized into three technical sessions. The first session was dedicated to Olympus and ACTS studies and experiments, the second session was focused on the propagation studies and measurements, and the third session covered computer-based propagation model development. In total, sixteen technical papers and some informal contributions were presented. Following NAPEX 15, the Advanced Communications Technology Satellite (ACTS) miniworkshop was held on 29 Jun. 1991, to review ACTS propagation activities, with emphasis on ACTS hardware development and experiment planning. Five papers were presented.

Proceedings of the Eighteenth NASA Propagation Experimenters Meeting (NAPEX 18) and the Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop

NASA Technical Reports Server (NTRS)

Davarian, Faramaz (Editor)

1994-01-01

The NASA Propagation Experimenters Meeting (NAPEX), supported by the NASA Propagation Program, is convened annually to discuss studies made on radio wave propagation by investigators from domestic and international organizations. Participants included representatives from Canada, the Netherlands, England, and the United States, including researchers from universities, government agencies, and private industry. The meeting was organized into two technical sessions. The first session was dedicated to slant path propagation studies and experiments. The second session focused on propagation studies for mobile, personal, and sound broadcast systems. In total, 14 technical papers and some informal contributions were presented. Preceding NAPEX_17, the Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop was held to review ACTS propagation activities.

PS2007 Satellite Meeting on Photosynthetic Antennas, 19-22 July 2007, Drymen, Scotland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robert E. Blankenship

2009-06-04

A Satellite Workshop of the 14th International Congress on Photosynthesis on the topic of photosynthetic light-harvesting systems was held on 18-21 July 2007, at the Buchanan Arms Hotel in Drymen, Scotland, near Glasgow. This meeting continued the tradition of satellite light-harvesting conferences occurring prior to the last five international photosynthesis congresses in Japan, France, Hungary, Australia and Canada, dating from 1992. With an attendance of 124 participants, this Workshop represents an intimate gathering of scientists interested in a thorough coverage of the light-harvesting aspects of photosynthesis. A significant amount of time was set aside for discussion and poster sessions. Themore » organizers were: Richard J. Cogdell, UK (Chairperson), Alastair T. Gardiner, UK, Conrad W. Mullineaux, UK, Robert A. Niederman, USA, Robert E. Blankenship, USA, Harry Frank, USA, Bruno Robert, France. Sessions were focused on new concepts relating to the function, regulation, assembly, photoprotection and evolution of a wide variety of antenna systems. Cutting-edge scientific methods used to study these systems that were covered included time-resolved and single-molecule spectroscopy, structure determination by X-ray diffraction, NMR and electron and atomic force microscopy, molecular genetics, protein chemistry, model systems and theory. A central theme was how emerging high-resolution structural information on antenna proteins continues to provide an enhanced understanding of areas ranging from the kinetics of energy transfer processes to the assembly of the photosynthetic apparatus.« less

Improving Quality and Access to Radiation Therapy-An IAEA Perspective.

PubMed

Abdel-Wahab, May; Zubizarreta, Eduardo; Polo, Alfredo; Meghzifene, Ahmed

2017-04-01

The International Atomic Energy Agency (IAEA) has been involved in radiation therapy since soon after its creation in 1957. In response to the demands of Member States, the IAEA׳s activities relating to radiation therapy have focused on supporting low- and middle-income countries to set up radiation therapy facilities, expand the scope of treatments, or gradually transition to new technologies. In addition, the IAEA has been very active in providing internationally harmonized guidelines on clinical, dosimetry, medical physics, and safety aspects of radiation therapy. IAEA clinical research has provided evidence for treatment improvement as well as highly effective resource-sparing interventions. In the process, training of researchers occurs through this program. To provide this support, the IAEA works with its Member States and multiple partners worldwide through several mechanisms. In this article, we review the main activities conducted by the IAEA in support to radiation therapy. IAEA support has been crucial for achieving tangible results in many low- and middle-income countries. However, long-term sustainability of projects can present a challenge, especially when considering health budget constraints and the brain drain of skilled professionals. The need for support remains, with more than 90% of patients in low-income countries lacking access to radiotherapy. Thus, the IAEA is expected to continue its support and strengthen quality radiation therapy treatment of patients with cancer. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Proceedings of the 16th NASA Propagation Experimenters Meeting (NAPEX 16) and the Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop

NASA Technical Reports Server (NTRS)

Davarian, Faramaz (Editor)

1992-01-01

The NASA Propagation Experimenters Meeting (NAPEX), supported by the NASA Propagation Program, is convened annually to discuss studies made on radio wave propagation by investigators from domestic and international organizations. NAPEX 16 was held on May 29, 1992 in Houston, Texas. The meeting was organized into two technical sessions. The first session was dedicated to slant path propagation studies and measurements. The second session focused on Olympus propagation measurements and results. Following NAPEX 16, the Advanced Communications Technology Satellite (ACTS) Miniworkshop was held to review ACTS propagation activities with emphasis on ACTS hardware development and experiment planning. Eight technical papers were presented by contributors from government agencies, private industry, and university research establishments.

Satellite battery testing status

NASA Astrophysics Data System (ADS)

Haag, R.; Hall, S.

1986-09-01

Because of the large numbers of satellite cells currently being tested and anticipated at the Naval Weapons Support Center (NAVWPNSUPPCEN) Crane, Indiana, satellite cell testing is being integrated into the Battery Test Automation Project (BTAP). The BTAP, designed to meet the growing needs for battery testing at the NAVWPNSUPPCEN Crane, will consist of several Automated Test Stations (ATSs) which monitor batteries under test. Each ATS will interface with an Automation Network Controller (ANC) which will collect test data for reduction.

Satellite battery testing status

NASA Technical Reports Server (NTRS)

Haag, R.; Hall, S.

1986-01-01

Because of the large numbers of satellite cells currently being tested and anticipated at the Naval Weapons Support Center (NAVWPNSUPPCEN) Crane, Indiana, satellite cell testing is being integrated into the Battery Test Automation Project (BTAP). The BTAP, designed to meet the growing needs for battery testing at the NAVWPNSUPPCEN Crane, will consist of several Automated Test Stations (ATSs) which monitor batteries under test. Each ATS will interface with an Automation Network Controller (ANC) which will collect test data for reduction.

Internet-Protocol-Based Satellite Bus Architecture Designed

NASA Technical Reports Server (NTRS)

Slywczak, Richard A.

2004-01-01

NASA is designing future complex satellite missions ranging from single satellites and constellations to space networks and sensor webs. These missions require more interoperability, autonomy, and coordination than previous missions; in addition, a desire exists to have scientists retrieve data directly from the satellite rather than a central distribution source. To meet these goals, NASA has been studying the possibility of extending the Transmission Control Protocol/Internet Protocol (TCP/IP) suite for spacebased applications.

A multiple functional connector for high-resolution optical satellites

NASA Astrophysics Data System (ADS)

She, Fengke; Zheng, Gangtie

2017-11-01

For earth observation satellites, perturbations from actuators, such as CMGs and momentum wheels, and thermal loadings from support structures often have significant impact on the image quality of an optical. Therefore, vibration isolators and thermal deformation releasing devices nowadays often become important parts of an image satellite. However, all these devices will weak the connection stiffness between the optical instrument and the satellite bus structure. This will cause concern of the attitude control system design for worrying about possible negative effect on the attitude control. Therefore, a connection design satisfying all three requirements is a challenge of advanced image satellites. Chinese scientists have proposed a large aperture high-resolution satellite for earth observation. To meet all these requirements and ensure image quality, specified multiple function connectors are designed to meet these challenging requirements, which are: isolating vibration, releasing thermal deformation and ensuring whole satellite dynamic properties [1]. In this paper, a parallel spring guide flexure is developed for both vibration isolation and thermal deformation releasing. The stiffness of the flexure is designed to meet the vibration isolation requirement. To attenuate vibration, and more importantly to satisfy the stability requirement of the attitude control system, metal damping, which has many merits for space applications, are applied in this connecter to provide a high damping ratio and nonlinear stiffness. The capability of the connecter for vibration isolation and attenuation is validated through numerical simulation and experiments. Connecter parameter optimization is also conducted to meet both requirements of thermal deformation releasing and attitude control. Analysis results show that the in-orbit attitude control requirement is satisfied while the thermal releasing performance is optimized. The design methods and analysis results are also

Proceedings of the Twentieth NASA Propagation Experimenters Meeting (NAPEX XX) and the Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop

NASA Technical Reports Server (NTRS)

Golshan, Nassar (Editor)

1996-01-01

The NASA Propagation Experimenters (NAPEX) Meeting and associated Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop convene yearly to discuss studies supported by the NASA Propagation Program. Representatives from the satellite communications (satcom)industry, academia, and government with an interest in space-ground radio wave propagation have peer discussion of work in progress, disseminate propagation results, and interact with the satcom industry. NAPEX XX, in Fairbanks, Alaska, June 4-5, 1996, had three sessions: (1) "ACTS Propagation Study: Background, Objectives, and Outcomes," covered results from thirteen station-years of Ka-band experiments; (2) "Propagation Studies for Mobile and Personal Satellite Applications," provided the latest developments in measurement, modeling, and dissemination of propagation phenomena of interest to the mobile, personal, and aeronautical satcom industry; and (3)"Propagation Research Topics," covered a range of topics including space/ground optical propagation experiments, propagation databases, the NASA Propagation Web Site, and revision plans for the NASA propagation effects handbooks. The ACTS Miniworkshop, June 6, 1996, covered ACTS status, engineering support for ACTS propagation terminals, and the ACTS Propagation Data Center. A plenary session made specific recommendations for the future direction of the program.

IAEA Sampling Plan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geist, William H.

2017-09-15

The objectives for this presentation are to describe the method that the IAEA uses to determine a sampling plan for nuclear material measurements; describe the terms detection probability and significant quantity; list the three nuclear materials measurement types; describe the sampling method applied to an item facility; and describe multiple method sampling.

Technical comparison of several global mobile satellite communications systems

NASA Astrophysics Data System (ADS)

Comparetto, Gary M.

The era of satellite-based mobile satellite communications (MSC) systems started with the first MARISAT satellite which was launched into a geostationary orbit over the Pacific Ocean in 1976 to provide communications between ships and shore stations. The combination of high cost and unacceptably large equipment has kept the space-based MSC systems from appealing to the wider market of personal mobile communications. The progress made over the last ten years, however, in digital voice processing, satellite technology, and component miniaturization has resulted in the viability of satellite-based mobile satellite communications systems to meet the growing market in personal mobile communications using handsets similar to those currently in use with land-based cellular systems. Three of the more mature LEO/MEO satellite systems are addressed in this paper including GLOBALSTAR, Iridium, and Odyssey. The system architectures of each system are presented along with a description of the satellite and user handset designs and the multiaccess techniques employed. It will be shown that, although a number of similarities exist among the system addressed, each system is unique in a variety of significant design areas. It is concluded that the technical feasibility of satellite-based mobile satellite communications systems seems to be secure. It will be challenging, however, for the vendors to actually develop and deploy these systems in a cost effective, timely, and reliable way that meets a continually evolving set of requirements based upon a rapidly changing technology base.

Satellite voice broadcase system study. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

Horstein, M.

1985-01-01

The feasibility of providing Voice of America (VOA) broadcasts by satellite relay was investigated. Satellite voice broadcast systems are described for three different frequency bands: HF, FHV, and L-band. Geostationary satellite configurations are considered for both frequency bands. A system of subsynchronous, circular satellites with an orbit period of 8 hours was developed for the HF band. The VHF broadcasts are provided by a system of Molniya satellites. The satellite designs are limited in size and weight to the capability of the STS/Centaur launch vehicle combination. At L-band, only four geostationary satellites are needed to meet the requirements of the complete broadcast schedule. These satellites are comparable in size and weight to current satellites designed for the direct broadcast of video program material.

Strengthened IAEA Safeguards-Imagery Analysis: Geospatial Tools for Nonproliferation Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pabian, Frank V

2012-08-14

This slide presentation focuses on the growing role and importance of imagery analysis for IAEA safeguards applications and how commercial satellite imagery, together with the newly available geospatial tools, can be used to promote 'all-source synergy.' As additional sources of openly available information, satellite imagery in conjunction with the geospatial tools can be used to significantly augment and enhance existing information gathering techniques, procedures, and analyses in the remote detection and assessment of nonproliferation relevant activities, facilities, and programs. Foremost of the geospatial tools are the 'Digital Virtual Globes' (i.e., GoogleEarth, Virtual Earth, etc.) that are far better than previouslymore » used simple 2-D plan-view line drawings for visualization of known and suspected facilities of interest which can be critical to: (1) Site familiarization and true geospatial context awareness; (2) Pre-inspection planning; (3) Onsite orientation and navigation; (4) Post-inspection reporting; (5) Site monitoring over time for changes; (6) Verification of states site declarations and for input to State Evaluation reports; and (7) A common basis for discussions among all interested parties (Member States). Additionally, as an 'open-source', such virtual globes can also provide a new, essentially free, means to conduct broad area search for undeclared nuclear sites and activities - either alleged through open source leads; identified on internet BLOGS and WIKI Layers, with input from a 'free' cadre of global browsers and/or by knowledgeable local citizens (a.k.a.: 'crowdsourcing'), that can include ground photos and maps; or by other initiatives based on existing information and in-house country knowledge. They also provide a means to acquire ground photography taken by locals, hobbyists, and tourists of the surrounding locales that can be useful in identifying and discriminating between relevant and non-relevant facilities and their

Tenth AMS Conference on Satellite Meteorology and Oceanography

NASA Technical Reports Server (NTRS)

Ferraro, R.; Colton, M.; Deblonde, G.; Jedlovec, G.; Lee, T.

2000-01-01

The American Meteorological Society held its Tenth Conference on Satellite Meteorology and Oceanography in conjunction with the 80th Annual Meeting in Long Beach, California. For the second consecutive conference, a format that consisted of primarily posters, complemented by invited theme oriented oral presentations, and panel discussions on various aspects on satellite remote sensing were utilized. Joint sessions were held with the Second Conference on Artificial Intelligence, the Eleventh Conference on Middle Atmosphere, and the Eleventh symposium on Global Change Studies. In total, there were 23 oral presentations, 170 poster presentations, and four panel discussions. Over 450 people representing a wide spectrum of the society attended one or more of the sessions in the five-day meeting. The program for the Tenth Conference on Satellite Meteorology and Oceanography can viewed in the October 1999 issue of the Bulletin.

Plasma Physics Network Newsletter, no. 5

NASA Astrophysics Data System (ADS)

1992-08-01

The fifth Plasma Physics Network Newsletter (IAEA, Vienna, Aug. 1992) includes the following topics: (1) the availability of a list of the members of the Third World Plasma Research Network (TWPRN); (2) the announcement of the fourteenth IAEA International Conference on Plasma Physics and Controlled Nuclear Fusion Research to be held in Wuerzburg, Germany, from 30 Sep. to 7 Oct. 1992; (3) the announcement of a Technical Committee Meeting on research using small tokamaks, organized by the IAEA as a satellite meeting to the aforementioned fusion conference; (4) IAEA Fellowships and Scientific Visits for the use of workers in developing member states, and for which plasma researchers are encouraged to apply through Dr. D. Banner, Head, Physics Section, IAEA, P.O. Box 100, A-1400 Vienna, Austria; (5) the initiation in 1993 of a new Coordinated Research Programme (CRP) on 'Development of Software for Numerical Simulation and Data Processing in Fusion Energy Research', as well as a proposed CRP on 'Fusion Research in Developing Countries using Middle- and Small-Scale Plasma Devices'; (6) support from the International Centre for Theoretical Physics (ICTP) for meetings held in Third World countries; (7) a report by W. Usada on Fusion Research in Indonesia; (8) News on ITER; (9) the Technical Committee Meeting planned 8-12 Sep. 1992, Canada, on Tokamak Plasma Biasing; (10) software made available for the study of tokamak transport; (11) the electronic mail address of the TWPRN; (12) the FAX, e-mail, and postal address for contributions to this plasma physics network newsletter.

Protocols for second-generation business satellites systems

NASA Astrophysics Data System (ADS)

Evans, B. G.; Coakley, F. P.; El Amin, M. H. M.

The paper discusses the nature and mix of traffic in business satellite systems and describes the limitations on the protocol imposed by the differing impairments of speech, video, and data. A simple TDMA system protocol is presented which meets the requirements of mixed-service operation. The efficiency of the protocol together with implications for allocation, scheduling and synchronisation are discussed. Future-generation satellites will probably use on-board processing. Some initial work on protocols that make use of on-board processing and the implications for satellite and earth-station equipment are presented.

Next generation satellite communications networks

NASA Astrophysics Data System (ADS)

Garland, P. J.; Osborne, F. J.; Streibl, I.

The paper introduces two potential uses for new space hardware to permit enhanced levels of signal handling and switching in satellite communication service for Canada. One application involves increased private-sector services in the Ku band; the second supports new personal/mobile services by employing higher levels of handling and switching in the Ka band. First-generation satellite regeneration and switching experiments involving the NASA/ACTS spacecraft are described, where the Ka band and switching satellite network problems are emphasized. Second-generation satellite development is outlined based on demand trends for more packet-based switching, low-cost earth stations, and closed user groups. A demonstration mission for new Ka- and Ku-band technologies is proposed, including the payload configuration. The half ANIK E payload is shown to meet the demonstration objectives, and projected to maintain a fully operational payload for at least 10 years.

International Scavenging for First Responder Guidance and Tools: IAEA Products

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stern, W.; Berthelot, L.; Bachner, K.

In fiscal years (FY) 2016 and 2017, with support from the U.S. Department of Homeland Security (DHS), Brookhaven National Laboratory (BNL) examined the International Atomic Energy Agency (IAEA) radiological emergency response and preparedness products (guidance and tools) to determine which of these products could be useful to U.S. first responders. The IAEA Incident and Emergency Centre (IEC), which is responsible for emergency preparedness and response, offers a range of tools and guidance documents for responders in recognizing, responding to, and recovering from radiation emergencies and incidents. In order to implement this project, BNL obtained all potentially relevant tools and productsmore » produced by the IAEA IEC and analyzed these materials to determine their relevance to first responders in the U.S. Subsequently, BNL organized and hosted a workshop at DHS National Urban Security Technology Laboratory (NUSTL) for U.S. first responders to examine and evaluate IAEA products to consider their applicability to the United States. This report documents and describes the First Responder Product Evaluation Workshop, and provides recommendations on potential steps the U.S. federal government could take to make IAEA guidance and tools useful to U.S. responders.« less

Tracking and data relay satellite system (TDRSS) capabilities

NASA Astrophysics Data System (ADS)

Spearing, R. E.

1985-10-01

The Tracking and Data Relay Satellite System (TDRSS) is the latest implementation to tracking and data acquisition network for near-earth orbiting satellite support designed to meet the requirements of the current and projected (to the year 2000) satellite user community. The TDRSS consists of a space segment (SS) and a ground segment (GS) that fit within NASA's Space Network (SN) complex controlled at the Goddard Space Flight Center. The SS currently employs a single satellite, TDRS-1, with two additional satellites to be deployed in January 1986 and July 1986. The GS contains the communications and equipment required to manage the three TDR satellites and to transmit and receive information to and from TDRSS user satellites. Diagrams and tables illustrating the TDRSS signal characteristics, the situation of TDRSS within the SN, the SN operations and element interrelationships, as well as future plans for new missions are included.

Tracking and data relay satellite system (TDRSS) capabilities

NASA Technical Reports Server (NTRS)

Spearing, R. E.

1985-01-01

The Tracking and Data Relay Satellite System (TDRSS) is the latest implementation to tracking and data acquisition network for near-earth orbiting satellite support designed to meet the requirements of the current and projected (to the year 2000) satellite user community. The TDRSS consists of a space segment (SS) and a ground segment (GS) that fit within NASA's Space Network (SN) complex controlled at the Goddard Space Flight Center. The SS currently employs a single satellite, TDRS-1, with two additional satellites to be deployed in January 1986 and July 1986. The GS contains the communications and equipment required to manage the three TDR satellites and to transmit and receive information to and from TDRSS user satellites. Diagrams and tables illustrating the TDRSS signal characteristics, the situation of TDRSS within the SN, the SN operations and element interrelationships, as well as future plans for new missions are included.

Space Weather Concerns for All-Electric Propulsion Satellites

NASA Astrophysics Data System (ADS)

Horne, Richard B.; Pitchford, David

2015-08-01

The introduction of all-electric propulsion satellites is a game changer in the quest for low-cost access to space. It also raises new questions for satellite manufacturers, operators, and the insurance industry regarding the general risks and specifically the threat of adverse space weather. The issues surrounding this new concept were discussed by research scientists and up to 30 representatives from the space industry at a special meeting at the European Space Weather Week held in November 2014. Here we report on the discussions at that meeting. We show that for a satellite undergoing electric orbit raising for 200 days the radiation dose due to electrons is equivalent to approximately 6.7 year operation at geostationary orbit or approximately half the typical design life. We also show that electrons can be injected into the slot region (8000 km) where they pose a risk of satellite internal charging. The results highlight the importance of additional radiation protection. We also discuss the benefits, the operational considerations, the other risks from the Van Allen radiation belts, the new business opportunities for space insurance, and the need for space situation awareness in medium Earth orbit where electric orbit raising takes place.

Using models in cardiovascular research: report on the satellite meeting to the International Congress of Physiological Sciences, Models in Cardiovascular Research.

PubMed

Doggrell, S A; Chan, V

2001-10-01

Humans have used animals for centuries to understand their own biology. From September 2-4, 2001, scientists from around the world converged on Brisbane, in Australia, to discuss the use of animal models in cardiovascular research at a satellite meeting to the 34th International Congress of Physiological Sciences (August 26-September 1, 2001, Christchurch, New Zealand). The appropriateness of each model to the human disease was a major consideration. Other themes were the use of models to understand pathological processes, and to determine potential new targets for pharmacological intervention.

Internetworking satellite and local exchange networks for personal communications applications

NASA Technical Reports Server (NTRS)

Wolff, Richard S.; Pinck, Deborah

1993-01-01

The demand for personal communications services has shown unprecedented growth, and the next decade and beyond promise an era in which the needs for ubiquitous, transparent and personalized access to information will continue to expand in both scale and scope. The exchange of personalized information is growing from two-way voice to include data communications, electronic messaging and information services, image transfer, video, and interactive multimedia. The emergence of new land-based and satellite-based wireless networks illustrates the expanding scale and trend toward globalization and the need to establish new local exchange and exchange access services to meet the communications needs of people on the move. An important issue is to identify the roles that satellite networking can play in meeting these new communications needs. The unique capabilities of satellites, in providing coverage to large geographic areas, reaching widely dispersed users, for position location determination, and in offering broadcast and multicast services, can complement and extend the capabilities of terrestrial networks. As an initial step in exploring the opportunities afforded by the merger of satellite-based and land-based networks, several experiments utilizing the NASA ACTS satellite and the public switched local exchange network were undertaken to demonstrate the use of satellites in the delivery of personal communications services.

Proceedings of the Thirteenth NASA Propagation Experimenters Meeting (NAPEX 13)

NASA Technical Reports Server (NTRS)

Davarian, Faramaz (Editor)

1989-01-01

The NASA Propagation Experimenters Meeting (NAPEX), supported by the NASA Propagation Program, is convened annually to discuss studies made on radio wave propagation by investigators from domestic and international organizations. The meeting was organized into three technical sessions: the first focused on mobile satellite propagation; the second examined the propagation effects for frequencies above 10 GHz; and the third addressed studies devoted exclusively to the Olympus/Advanced Communications Technology Satellite (ACTS) Program.

On-board attitude determination for the Explorer Platform satellite

NASA Technical Reports Server (NTRS)

Jayaraman, C.; Class, B.

1992-01-01

This paper describes the attitude determination algorithm for the Explorer Platform satellite. The algorithm, which is baselined on the Landsat code, is a six-element linear quadratic state estimation processor, in the form of a Kalman filter augmented by an adaptive filter process. Improvements to the original Landsat algorithm were required to meet mission pointing requirements. These consisted of a more efficient sensor processing algorithm and the addition of an adaptive filter which acts as a check on the Kalman filter during satellite slew maneuvers. A 1750A processor will be flown on board the satellite for the first time as a coprocessor (COP) in addition to the NASA Standard Spacecraft Computer. The attitude determination algorithm, which will be resident in the COP's memory, will make full use of its improved processing capabilities to meet mission requirements. Additional benefits were gained by writing the attitude determination code in Ada.

NASA Satellite Laser Ranging Network

NASA Technical Reports Server (NTRS)

Carter, David L.

2004-01-01

I will be participating in the International Workshop on Laser Ranging. I will be presenting to the International Laser Ranging Service (ILRS) general body meeting on the recent accomplishments and status of the NASA Satellite Laser Ranging (SLR) Network. The recent accomplishments and NASA's future plans will be outlined and the benefits to the scientific community will be addressed. I am member of the ILRS governing board, the Missions working group, and the Networks & Engineering working group. I am the chairman of the Missions Working and will be hosting a meeting during the week of the workshop. I will also represent the NASA SLR program at the ILRS governing board and other working group meetings.

RELAP5 posttest calculation of IAEA-SPE-4

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petelin, S.; Mavko, B.; Parzer, I.

The International Atomic Energy Agency`s Fourth Standard Problem Exercise (IAEA-SPE-4) was performed at the PMK-2 facility. The PMK-2 facility is designed to study processes following small- and medium-size breaks in the primary system and natural circulation in VVER-440 plants. The IAEA-SPE-4 experiment represents a cold-leg side small break, similar to the IAEA-SPE-2, with the exception of the high-pressure safety injection being unavailable, and the secondary side bleed and feed initiation. The break valve was located at the dead end of a vertical downcomer, which in fact simulates a break in the reactor vessel itself, and should be unlikely to happenmore » in a real nuclear power plant (NPP). Three different RELAP5 code versions were used for the transient simulation in order to assess the calculations with test results.« less

Multichannel demultiplexer/demodulator technologies for future satellite communication systems

NASA Technical Reports Server (NTRS)

Ivancic, William D.; Budinger, James M.; Staples, Edward J.; Abramovitz, Irwin; Courtois, Hector A.

1992-01-01

NASA-Lewis' Space Electronics Div. supports ongoing research in advanced satellite communication architectures, onboard processing, and technology development. Recent studies indicate that meshed VSAT (very small aperture terminal) satellite communication networks using FDMA (frequency division multiple access) uplinks and TDMA (time division multiplexed) downlinks are required to meet future communication needs. One of the critical advancements in such a satellite communication network is the multichannel demultiplexer/demodulator (MCDD). The progress is described which was made in MCDD development using either acousto-optical, optical, or digital technologies.

Satellite voice broadcast system study, volume 2

NASA Technical Reports Server (NTRS)

Horstein, M.

1985-01-01

This study investigates the feasibility of providing Voice of America (VOA) broadcasts by satellite relay, rather than via terrestrial relay stations. Satellite voice broadcast systems are described for three different frequency bands: HF (26 MHz), VHF (68 MHz), and L-band (1.5 GHz). The geographical areas of interest at HF and L-band include all major land masses worldwide with the exception of the U.S., Canada, and Australia. Geostationary satellite configurations are considered for both frequency bands. In addition, a system of subsynchronous, circular satellites with an orbit period of 8 hours is developed for the HF band. VHF broadcasts, which are confined to the Soviet Union, are provied by a system of Molniya satellites. Satellites intended for HF or VHF broadcastinbg are extremely large and heavy. Satellite designs presented here are limited in size and weight to the capability of the STS/Centaur launch vehicle combination. Even so, at HF it would take 47 geostationary satellites or 20 satellites in 8-hour orbits to fully satisfy the voice-channel requirements of the broadcast schedule provided by VOA. On the other hand, three Molniya satellites suffice for the geographically restricted schedule at VHF. At L-band, only four geostationary satellites are needed to meet the requirements of the complete broadcast schedule. Moreover, these satellites are comparable in size and weight to current satellites designed for direct broadcast of video program material.

10 CFR 150.17a - Compliance with requirements of US/IAEA Safeguards Agreement.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 2 2011-01-01 2011-01-01 false Compliance with requirements of US/IAEA Safeguards... Authority in Agreement States § 150.17a Compliance with requirements of US/IAEA Safeguards Agreement. (a... shall take other action as may be necessary to implement the US/IAEA Safeguards Agreement, as described...

10 CFR 150.17a - Compliance with requirements of US/IAEA Safeguards Agreement.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Compliance with requirements of US/IAEA Safeguards... Authority in Agreement States § 150.17a Compliance with requirements of US/IAEA Safeguards Agreement. (a... shall take other action as may be necessary to implement the US/IAEA Safeguards Agreement, as described...

Engineering management consideration for an integrated aeronautical mobile satellite service

NASA Astrophysics Data System (ADS)

Belcher, John M.

In order to meet local air traffic control terminal requirements as well as national and transborder requirements, countries have developed communications, navigation, and surveillance (CNS) systems having little systems integration and a solely ground-based solution to air traffic control problems. It is believed that the application of satellite technology is the only currently viable solution that will enable international civil aviation to overcome the shortcomings of the presently available CNS systems. If properly implemented, available satellite system technology integrated with avionics and ground based capabilities, can be used to meet new global aviation demands. A clear transition plan has to be implemented so as to ensure continuity of service, recognize user-borne costs, and satisfy institutional and national objectives in the progress toward a universal air traffic management (ATM) system. ATM systems design should rely on a modular approach for flexibility and upgrading. An aeronautical mobile satellite service is intended to provide a worldwide satellite data link and direct air/ground voice communication. Institutional and financial roadblocks for implemetation of a global based approach will likely be far greater than technical constraints.

A digital simulation of message traffic for natural disaster warning communications satellite

NASA Technical Reports Server (NTRS)

Hein, G. F.; Stevenson, S. M.

1972-01-01

Various types of weather communications are required to alert industries and the general public about the impending occurrence of tornados, hurricanes, snowstorms, floods, etc. A natural disaster warning satellite system has been proposed for meeting the communications requirements of the National Oceanic and Atmospheric Administration. Message traffic for a communications satellite was simulated with a digital computer in order to determine the number of communications channels to meet system requirements. Poisson inputs are used for arrivals and an exponential distribution is used for service.

Recommended satellite imagery capabilities for disaster management

NASA Technical Reports Server (NTRS)

Richards, P. B.; Robinove, C. J.; Wiesnet, D. R.; Salomonson, V. V.; Maxwell, M. S.

1982-01-01

This study explores the role that satellite imaging systems might play in obtaining information needed in the management of natural and manmade disasters. Information requirements which might conceivably be met by satellite were identified for over twenty disasters. These requirements covered pre-disaster mitigation and preparedness activities, disaster response activities, and post-disaster recovery activities. The essential imaging satellite characteristics needed to meet most of the information requirements are 30 meter (or finer) spatial resolution, frequency of observations of one week or less, data delivery times of one day or less, and stereo, synoptic all-weather coverage of large areas in the visible, near infrared, thermal infrared and microwave bands. Of the current and planned satellite systems investigated for possible application to disaster management, Landsat-D and SPOT appear to have the greatest potential during disaster mitigation and preparedness activities, but all satellites studied have serious deficiencies during response and recovery activities. Several strawman concepts are presented for a satellite system optimized to support all disaster management activities.

Use of open source information and commercial satellite imagery for nuclear nonproliferation regime compliance verification by a community of academics

NASA Astrophysics Data System (ADS)

Solodov, Alexander

The proliferation of nuclear weapons is a great threat to world peace and stability. The question of strengthening the nonproliferation regime has been open for a long period of time. In 1997 the International Atomic Energy Agency (IAEA) Board of Governors (BOG) adopted the Additional Safeguards Protocol. The purpose of the protocol is to enhance the IAEA's ability to detect undeclared production of fissile materials in member states. However, the IAEA does not always have sufficient human and financial resources to accomplish this task. Developed here is a concept for making use of human and technical resources available in academia that could be used to enhance the IAEA's mission. The objective of this research was to study the feasibility of an academic community using commercially or publicly available sources of information and products for the purpose of detecting covert facilities and activities intended for the unlawful acquisition of fissile materials or production of nuclear weapons. In this study, the availability and use of commercial satellite imagery systems, commercial computer codes for satellite imagery analysis, Comprehensive Test Ban Treaty (CTBT) verification International Monitoring System (IMS), publicly available information sources such as watchdog groups and press reports, and Customs Services information were explored. A system for integrating these data sources to form conclusions was also developed. The results proved that publicly and commercially available sources of information and data analysis can be a powerful tool in tracking violations in the international nuclear nonproliferation regime and a framework for implementing these tools in academic community was developed. As a result of this study a formation of an International Nonproliferation Monitoring Academic Community (INMAC) is proposed. This would be an independent organization consisting of academics (faculty, staff and students) from both nuclear weapon states (NWS) and

The impact of council directive 2011/70/EURATOM and IAEA joint convention review meetings on the ongoing establishment of the Portuguese regulatory framework and on the future of national radioactive waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paiva, Isabel; Trindade, Romao B.

Council Directive 2011/70/EURATOM of 19 July 2011, establishing a Community framework for the responsible and safe management of spent fuel and radioactive waste will enter in force August 2013 in all EU Member States. Portugal has already started preparing its legislative framework to accommodate the new legislative piece. However, the first report of Portugal to the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management of the IAEA, in Vienna, 2012, has shown that Portugal still has many steps to overcome to establish a successful and effective basic regulatory framework. The existencemore » of many competent authorities related to the radiological protection area and a newly independent commission that is still looking on how to fulfill its regulator role in other areas such as the radioactive waste management makes quite challenging the full application of the new directive as well as compliance that Portugal will have to show in the next Joint Convention review meeting in order to meet the obligations of the Convention. In this paper, the reality of the regulatory Portuguese framework on radiological protection, nuclear safety and radioactive waste management is presented. Discussion of the future impact of the new legislation and its consequences such as the need to setup the national program on radioactive waste management is critical discussed. (authors)« less

Four Years of Practical Arrangements between IAEA and Moscow SIA 'Radon': Preliminary Results - 13061

DOE Office of Scientific and Technical Information (OSTI.GOV)

Batyukhnova, O.G.; Karlina, O.K.; Neveikin, P.P.

The International Education Training Centre (IETC) at Moscow State Unitary Enterprise Scientific and Industrial Association 'Radon' (SIA 'Radon'), in co-operation with the International Atomic Energy Agency (IAEA), has developed expertise and provided training to waste management personnel for the last 15 years. Since 1997, the educational system of the enterprise with the support of the IAEA has acquired an international character: more than 470 experts from 35 countries- IAEA Member States completed the professional development. Training is conducted at various thematic courses or fellowships for individual programs and seminars on IAEA technical projects. In June 2008 a direct agreement (Practicalmore » Arrangements) was signed between SIA 'Radon' and the IAEA on cooperation in the field of development of new technologies, expert's advice to IAEA Member States, and, in particular, the training of personnel in the field of radioactive waste management (RWM), which opens up new perspectives for fruitful cooperation of industry professionals. The paper summarizes the current experience of the SIA 'Radon' in the organization and implementation of the IAEA sponsored training and others events and outlines some of strategic educational elements, which IETC will continue to pursue in the coming years. (authors)« less

Satellite instrument provides nighttime sensing capability

NASA Astrophysics Data System (ADS)

Showstack, Randy

2012-12-01

"This is not your father's low-light sensor," Steve Miller, senior research scientist and deputy director of the Cooperative Institute for Research in the Atmosphere at Colorado State University, Fort Collins, said at a 5 December news briefing at the AGU Fall Meeting. He and others at the briefing were showing off the nighttime sensing capability of the day/night band of the Visible Infrared Imaging Radiometer Suite (VIIRS) of instruments onboard the Suomi National Polar-orbiting Partnership (NPP) Earth-observing research satellite, a joint NASA and National Oceanic and Atmospheric Administration (NOAA) satellite that was launched on 28 October 2011. Noting that low-light satellite technology has been available for about 40 years, Miller said that the VIIRS day/night band "is truly a paradigm shift in the technology and capability."

Strengthening radiopharmacy practice in IAEA Member States.

PubMed

Duatti, Adriano; Bhonsle, Uday

2013-05-01

Radiopharmaceuticals are essential components of nuclear medicine procedures. Without radiopharmaceuticals nuclear medicine procedures cannot be performed. Therefore it could be said that 'No radiopharmaceutical-no nuclear medicine.' A good radiopharmacy practice supports nuclear medicine activities by producing radiopharmaceuticals that are safe and are of the required quality in a consistent way. As with any medicinal product, radiopharmaceuticals are required to be produced under carefully controlled conditions and are tested for their quality, prior to the administration to patients, using validated standard operating procedures. These procedures are based on the principles of Good Manufacturing Practice (GMP). The GMP principles are based on scientific knowledge and applicable regulatory requirements and guidance related to radiopharmaceutical productions and use. The International Atomic Energy Agency (IAEA) is committed to promote, in the Member States (MS), a rational and practical approach for the implementation of GMP for compounding or manufacturing of diagnostic or therapeutic radiopharmaceuticals. To pursue this goal the IAEA has developed various mechanisms and collaborations with individual experts in the field and with relevant national and international institutions or organizations. IAEA's activities in promoting radiopharmaceutical science include commissioning expert advice in the form of publications on radiopharmaceutical production, quality control and usage, producing technical guidance on production and regulatory aspects related to new radiopharmaceuticals, creating guidance documentation for self or internal audits of radiopharmaceutical production facilities, producing guidance on implementation of Quality Management System and GMP in radiopharmacy, assisting in creation of specific radiopharmaceutical monographs for the International Pharmacopoeia, and developing radiopharmacy-related human resource capabilities in MS through individual

A land mobile satellite data system

NASA Technical Reports Server (NTRS)

Kent, John D. B.

1990-01-01

The Telesat Mobile Incorporated (TMI) Mobile Data System (MDS) was developed to apply satellite technology to the transportation industry's requirement for a fleet management system. It will provide two-way messaging and automatic position reporting capabilities between dispatch centers and customers' fleets of trucks. The design was based on the Inmarsat L-Band space segment with system link parameters and margins adjusted to meet the land mobile satellite channel characteristics. The system interfaces with the Teleglobe Des Laurentides earth station at Weir, Quebec. The signaling protocols were derived from the Inmarsat Standard C packet signalling system with unique trucking requirements incorporated where necessary.

Dual use of distributed remote sensing satellites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Canavan, G.H.

1992-12-02

Satellites can serve both defense and the environment, simultaneously monitoring preparations for aggression, the environment, pollution, and natural disasters. These applications have been discussed extensively in international meetings, which have produced specific projects for cooperation and growing acceptance of dual-use concepts.

Dual use of distributed remote sensing satellites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Canavan, G.H.

1993-03-01

Satellites can serve both defense and the environment, simultaneously monitoring preparations for aggression, the environment, pollution, and natural disasters. These applications have been discussed extensively in international meetings, which have produced specific projects for cooperation and growing acceptance of dual-use concepts.

Dual use of distributed remote sensing satellites

NASA Astrophysics Data System (ADS)

Canavan, G. H.

1992-12-01

Satellites can serve both defense and the environment, simultaneously monitoring preparations for aggression, the environment, pollution, and natural disasters. These applications have been discussed extensively in international meetings, which have produced specific projects for cooperation and growing acceptance of dual-use concepts.

Nano-Satellite Avionics

NASA Technical Reports Server (NTRS)

Culver, Harry

1999-01-01

Abstract NASA's Goddard Space Flight Center (GSFC) is currently developing a new class of satellites called the nano-satellite (nano-sat). A major objective of this development effort is to provide the technology required to enable a constellation of tens to hundreds of nano-satellites to make both remote and in-situ measurements from space. The Nano-sat will be a spacecraft weighing a maximum of 10 kg, including the propellant mass, and producing at least 5 Watts of power to operate the spacecraft. The electronics are required to survive a total radiation dose rate of 100 krads for a mission lifetime of two years. There are many unique challenges that must be met in order to develop the avionics for such a spacecraft. The first challenge is to develop an architecture that will operate on the allotted 5 Watts and meet the diverging requirements of multiple missions. This architecture will need to incorporate a multitude of new advanced microelectronic technologies. The microelectronics developed must be a modular and scalable packaging of technology to solve the problem of developing a solution to both reduce cost and meet the requirements of various missions. This development will utilize the most cost effective approach, whether infusing commercially driven semiconductor devices into spacecraft applications or partnering with industry to design and develop low cost, low power, low mass, and high capacity data processing devices. This paper will discuss the nano-sat architecture and the major technologies that will be developed. The major technologies that will be covered include: (1) Light weight Low Power Electronics Packaging, (2) Radiation Hard/Tolerant, Low Power Processing Platforms, (3) High capacity Low Power Memory Systems (4) Radiation Hard reconfiguragble field programmable gate array (rFPGA)

NASA as a Catalyst: Use of Satellite Data in the States

NASA Technical Reports Server (NTRS)

Warnecke, Lisa

1997-01-01

NASA revolutionized our view of the world in 1972 with the launch of the first satellite to monitor the Earth. Recognizing the importance of states in governing the United States, NASA then established a program in the late 1970s to educate and assist states in using satellite data products. This report reviews this brief, but beneficial program that laid a foundation and catalyzed satellite data work that continues today in several states. More recently, outreach efforts as part of NASAs Mission to Planet Earth program and growing state government roles, responsibilities, and initiatives led NASA to begin a new effort in 1994 to understand and work effectively with states. This effort included an investigation and synthesis of current satellite data conditions in each of the 50 states that are included in this report. It provided strong evidence that some state governments are applying satellite data to an increasing array of government needs, while other states have very limited applications to date. A wide range of satellite data applications in executive branch agencies are described, as well as the recent status of the Gap Analysis Program in each of the states with this program. The report also reviews the status of satellite data and geographic information coordination efforts in each of the 50 states. In addition to this investigation, NASA convened a meeting of representatives of 12 states experienced with satellite data to identify future satellite data uses and needs, as well as NASA opportunities to enhance the utility of satellite data products. The findings and recommendations from this meeting, the 50 state investigations, and NASAs past state programs are also included in the report; they provide the rationale for NASA to establish a new outreach effort with state governments in the late 1990s.

Strengthening IAEA Safeguards for Research Reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reid, Bruce D.; Anzelon, George A.; Budlong-Sylvester, Kory

During their December 10-11, 2013, workshop in Grenoble France, which focused on the history and future of safeguarding research reactors, the United States, France and the United Kingdom (UK) agreed to conduct a joint study exploring ways to strengthen the IAEA’s safeguards approach for declared research reactors. This decision was prompted by concerns about: 1) historical cases of non-compliance involving misuse (including the use of non-nuclear materials for production of neutron generators for weapons) and diversion that were discovered, in many cases, long after the violations took place and as part of broader pattern of undeclared activities in half amore » dozen countries; 2) the fact that, under the Safeguards Criteria, the IAEA inspects some reactors (e.g., those with power levels under 25 MWt) less than once per year; 3) the long-standing precedent of States using heavy water research reactors (HWRR) to produce plutonium for weapons programs; 4) the use of HEU fuel in some research reactors; and 5) various technical characteristics common to some types of research reactors that could provide an opportunity for potential proliferators to misuse the facility or divert material with low probability of detection by the IAEA. In some research reactors it is difficult to detect diversion or undeclared irradiation. In addition, infrastructure associated with research reactors could pose a safeguards challenge. To strengthen the effectiveness of safeguards at the State level, this paper advocates that the IAEA consider ways to focus additional attention and broaden its safeguards toolbox for research reactors. This increase in focus on the research reactors could begin with the recognition that the research reactor (of any size) could be a common path element on a large number of technically plausible pathways that must be considered when performing acquisition pathway analysis (APA) for developing a State Level Approach (SLA) and Annual Implementation Plan

University Satellite Campus Management Models

ERIC Educational Resources Information Center

Fraser, Doug; Stott, Ken

2015-01-01

Among the 60 or so university satellite campuses in Australia are many that are probably failing to meet the high expectations of their universities and the communities they were designed to serve. While in some cases this may be due to the demand driven system, it may also be attributable in part to the ways in which they are managed. The…

75 FR 6070 - Notice of Public Meeting on the International Atomic Energy Agency Basic Safety Standards Version...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-05

... Energy Agency Basic Safety Standards Version 3.0, Draft Safety Requirements DS379 AGENCY: Nuclear Regulatory Commission. ACTION: Notice of Public Meeting on the International Atomic Energy Agency Basic... development of U.S. Government comments on this International Atomic Energy Agency (IAEA) draft General Safety...

77 FR 57558 - Notice of Public Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-18

.... SUMMARY: The Advisory Committee on Commercial Remote Sensing (ACCRES) will meet September 24, 2012. DATES... on long-range and short-range strategies for the licensing of commercial remote sensing satellite...

Training activities at FSUE 'RADON' and Lomonosov's Moscow state university under practical arrangements with IAEA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Batyukhnova, O.G.; Karlina, O.K.; Neveykin, P.P.

The International Education Training Centre (IETC) at Moscow Federal State Unitary Enterprise (FSUE) 'Radon', in co-operation with the International Atomic Energy Agency (IAEA), has developed expertise and provided training to waste management personnel for the last 15 years. Since 1997, the educational system of the enterprise with the support of the IAEA has acquired an international character: more than 470 experts from 35 countries - IAEA Member States completed the professional development. Training is conducted at various thematic courses or fellowships for individual programs and seminars on IAEA technical projects. In June 2008 a direct agreement (Practical Arrangements) has beenmore » signed between FSUE 'Radon' and the IAEA on cooperation in the field of development of new technologies, expert's advice to IAEA Member States, and, in particular, the training of personnel in the field of radioactive waste management (RWM), which opens up new perspectives for fruitful cooperation of industry professionals. A similar agreement - Practical Arrangements - has been signed between Lomonosov's MSU and the IAEA in 2012. In October 2012 a new IAEA two-weeks training course started at Lomonosov's MSU and FSUE 'Radon' in the framework of the Practical Agreements signed. Pre-disposal management of waste was the main topic of the courses. The paper summarizes the current experience of the FSUE 'Radon' in the organization and implementation of the IAEA sponsored training and others events and outlines some of strategic educational elements, which IETC will continue to pursue in the coming years. (authors)« less

The next generation of Palapa satellite (Palapa-C)

NASA Astrophysics Data System (ADS)

Setiawan, Bambang

The Indonesian Palapa Communication Satellite System was established in Aug. 1976 when the first satellite of Palapa A series (Palapa A1) began operation. The system is owned and operated by PT. Telekomunikasi Indonesia (Telkom), which is a state owned company. The purpose of the system was to unify the telecommunications of the nation. Many years of operation have shown that satellite technology is the best solution for improving telecommunications in Indonesia. The system was started with 2 (two) satellites, each with 12 transponders (for a total of 24), and 40 earth stations. Now the system has 3 (three) satellites, each with 24 transponders (for a total of 72 transponders), and thousands of earth stations. The services have been extended to satisfy the requirements of the region as well as the original objectives. The use of satellite transponders in the region is increasing rapidly. In the next ten years, opportunities in the satellite communications business will become even more attractive. The next generation Palapa-C will incorporate improvements in capacity, quality, and coverage. The new frequency bands (ku- and Extended-C Band) will be used to meet the new transponder capacity requirements.

How to Handle a Satellite Change in an Operational TWSTFT Network?

DTIC Science & Technology

2010-11-01

42 nd Annual Precise Time and Time Interval (PTTI) Meeting 285 HOW TO HANDLE A SATELLITE CHANGE IN AN OPERATIONAL TWSTFT NETWORK...way satellite time and frequency transfer ( TWSTFT ) is a powerful technique because of its real-time capabilities. In principle, the time difference...between remote clocks is almost instantaneously known after a measurement session. Long-term TWSTFT operations have required changes between

Combined Release and Radiation Effects Satellite (CRRES) experiments data collection, analysis, and publication

NASA Technical Reports Server (NTRS)

Long, Terry N.; Alzmann, Melanie O.

1992-01-01

The Combined Release and Radiation Effects Satellite (CRRES) program experiments data collection, analysis, and publication activities are described. These activities were associated with both the satellite chemical release and a planned Puerto Rico sounding rocket campaign. To coordinate these activities, a working group meeting was organized and conducted.

Satellite Remote Sensing of Aerosol Forcing

NASA Technical Reports Server (NTRS)

Remer, Lorraine; Kaufman, Yoram; Ramaprasad, Jaya; Procopio, Aline; Levin, Zev

1999-01-01

Aerosol and cloud impacts on the earth's climate become a recent hot topic in climate studies. Having near future earth observing satellites, EOS-AM1 (Earth Observing System-AM1), ENVISAT (Environmental Satellites) and ADEOS-2 (Advanced Earth Observation Satellite-2), it will be a good timing to discuss how to obtain and use the microphysical parameters of aerosols and clouds for studying their climate impacts. Center for Climate System Research (CCSR) of the University of Tokyo invites you to 'Symposium on synergy between satellite-remote sensing and climate modeling in aerosol and cloud issues.' Here, we like to discuss the current and future issues in the remote sensing of aerosol and cloud microphysical parameters and their climate modeling studies. This workshop is also one of workshop series on aerosol remote sensing held in 1996, Washington D. C., and Meribel, France in 1999. It should be reminded that NASDA/ADEOS-1 & -2 (National Space Development Agency of Japan/Advanced Earth Observation Satellite-1 & -2) Workshop will be held in the following week (Dec. 6-10, 1999), so that this opportunity will be a perfect period for you to attend two meetings for satellite remote sensing in Japan. A weekend in Kyoto, the old capital of Japan, will add a nice memory to your visiting Japan. *Issues in the symposium: 1) most recent topics in aerosol and cloud remot sensing, and 2) utility of satellite products on climate modeling of cloud-aerosol effects.

Space Solar Power: Satellite Concepts

NASA Technical Reports Server (NTRS)

Little, Frank E.

1999-01-01

Space Solar Power (SSP) applies broadly to the use of solar power for space related applications. The thrust of the NASA SSP initiative is to develop concepts and demonstrate technology for applying space solar power to NASA missions. Providing power from satellites in space via wireless transmission to a receiving station either on earth, another celestial body or a second satellite is one goal of the SSP initiative. The sandwich design is a satellite design in which the microwave transmitting array is the front face of a thin disk and the back of the disk is populated with solar cells, with the microwave electronics in between. The transmitter remains aimed at the earth in geostationary orbit while a system of mirrors directs sunlight to the photovoltaic cells, regardless of the satellite's orientation to the sun. The primary advantage of the sandwich design is it eliminates the need for a massive and complex electric power management and distribution system for the satellite. However, it requires a complex system for focusing sunlight onto the photovoltaic cells. In addition, positioning the photovoltaic array directly behind the transmitting array power conversion electronics will create a thermal management challenge. This project focused on developing designs and finding emerging technology to meet the challenges of solar tracking, a concentrating mirror system including materials and coatings, improved photovoltaic materials and thermal management.

American Radium Society 92nd Annual Meeting.

PubMed

Jani, Ashesh B; Le, Quynh-Thu; Michalski, Jeff J; Sawaya, Raymond; Wilson, Lynn D

2010-08-01

We provide a summary of the 92nd Annual Meeting of the American Radium Society (ARS), the oldest organization devoted to the study of cancer. This May 2010 meeting included a postgraduate course/contouring laboratory, seven scientific sessions, two keynote lectures, one Janeway lecture, four Panel presentations, one debate, one satellite symposium and 107 poster presentations--details of each of these activities are provided. All of these academic activities revolved around the major meeting theme of 'Improved Outcomes Through Judicious Applications of Advanced Technology'.

The IAEA stopping power database, following the trends in stopping power of ions in matter

NASA Astrophysics Data System (ADS)

Montanari, C. C.; Dimitriou, P.

2017-10-01

The aim of this work is to present an overview of the state of art of the energy loss of ions in matter, based on the new developments in the stopping power database of the International Atomic Energy Agency (IAEA). This exhaustive collection of experimental data, graphs, programs and comparisons, is the legacy of Helmut Paul, who made it accessible to the global scientific community, and has been extensively employed in theoretical and experimental research during the last 25 years. The field of stopping power in matter is evolving, with new trends in materials of interest, including oxides, nitrides, polymers, and biological targets. Our goal is to identify areas of interest and emerging data needs to meet the requirements of a continuously developing user community.

IAEA programs in empowering the nuclear medicine profession through online educational resources.

PubMed

Pascual, Thomas Nb; Dondi, Maurizio; Paez, Diana; Kashyap, Ravi; Nunez-Miller, Rodolfo

2013-05-01

The International Atomic Energy Agency's (IAEA) programme in human health aims to enhance the capabilities in Member States to address needs related to the prevention, diagnosis, and treatment of diseases through the application of nuclear techniques. It has the specific mission of fostering the application of nuclear medicine techniques as part of the clinical management of certain types of diseases. Attuned to the continuous evolution of this specialty as well as to the advancement and diversity of methods in delivering capacity building efforts in this digital age, the section of nuclear medicine of the IAEA has enhanced its program by incorporating online educational resources for nuclear medicine professionals into its repertoire of projects to further its commitment in addressing the needs of its Member States in the field of nuclear medicine. Through online educational resources such as the Human Health Campus website, e-learning modules, and scheduled interactive webinars, a validation of the commitment by the IAEA in addressing the needs of its Member States in the field of nuclear medicine is strengthened while utilizing the advanced internet and communications technology which is progressively becoming available worldwide. The Human Health Campus (www.humanhealth.iaea.org) is the online educational resources initiative of the Division of Human Health of the IAEA geared toward enhancing professional knowledge of health professionals in radiation medicine (nuclear medicine and diagnostic imaging, radiation oncology, and medical radiation physics), and nutrition. E-learning modules provide an interactive learning environment to its users while providing immediate feedback for each task accomplished. Webinars, unlike webcasts, offer the opportunity of enhanced interaction with the learners facilitated through slide shows where the presenter guides and engages the audience using video and live streaming. This paper explores the IAEA's available online

Face-offs in reproductive immunology: the Montreal forum meeting report.

PubMed

Croy, B Anne; Baines, Malcolm G

2004-10-01

The combined 12th International Congress of Immunology (ICI) and the 4th Annual Conference of the Federation of Clinical Immunological Societies (FOCIS) was held in Montreal, Canada July 18-23, 2004 and attracted over 6000 immunologists and almost 4000 abstracts. The host society, the Canadian Society for Immunology (CSI) spent many years in preparation for this large meeting and encouraged its members to propose topics for symposia and mini-symposia and to sponsor satellite meetings. With sponsorship of CSI; the Canadian Institutes of Health Research; the University of Guelph, Guelph, ON; Queen's University, Kingston, ON; McGill University, Montreal, QU, Canada; and the American Society for Reproductive Immunology, a focused, highly successful, one day satellite meeting on human uterine immunology was held. The highlights of the presentations and discussions are reported.

Professor Glyn O. Phillip's legacy within the IAEA programme on radiation and tissue banking.

PubMed

Morales Pedraza, Jorge

2017-08-19

Professor Phillips began his involvement in the implementation of this important IAEA programme, insisting that there were advantages to be gained by using the ionizing radiation technique to sterilize human and animal tissues, based on the IAEA experience gained in the sterilization of medical products. The outcome of the implementation of the IAEA programme on radiation and tissue banking demonstrated that Professor Phillips was right in his opinion.

Frequency stabilization for mobile satellite terminals via LORAN

NASA Technical Reports Server (NTRS)

Ernst, Gregory J.; Kee, Steven M.; Marquart, Robert C.

1990-01-01

Digital satellite communication systems require careful management of frequency stability. Historically, frequency stability has been accomplished by continuously powered, high cost, high performance reference oscillators. Today's low cost mobile satellite communication equipment must operate under wide ranging environmental conditions, stabilize quickly after application of power, and provide adequate performance margin to overcome RF link impairments unique to the land mobile environment. Methods for frequency stabilization in land mobile applications must meet these objectives without incurring excessive performance degradation. A frequency stabilization scheme utilizing the LORAN (Long Range Navigation) system is presented.

Reducing the risks from radon indoors: an IAEA perspective.

PubMed

Boal, T; Colgan, P A

2014-07-01

The IAEA has a mandate to develop, in collaboration with other relevant international organisations, 'standards of safety for protection of health and minimisation of danger to life and property', and to provide for the application of these standards. The most recent edition of the International Basic Safety Standards includes, for the first time, requirements to protect the public from exposure due to radon indoors. As a result, the IAEA has already developed guidance material in line with accepted best international practice and an international programme to assist its Member States in identifying and addressing high radon concentrations in buildings is being prepared. This paper overviews the current situation around the world and summarises the management approach advocated by the IAEA. A number of important scientific and policy issues are identified and discussed from the point-of-view of how they may impact on national action plans and strategies. Finally, the assistance and support available through the Agency is described. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Assessment of Alternative Funding Mechanisms for the IAEA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Toomey, Christopher; Wyse, Evan T.; Kurzrok, Andrew J.

While the International Atomic Energy Agency (IAEA) has enjoyed substantial success and prestige in the international community, there is growing concern that global demographic trends, advances in technology and the trend towards austerity in Member State budgets will stretch the Agency’s resources to a point where it may no longer be possible to execute its multifaceted mission in its entirety. As part of an ongoing effort by the Next Generation Safeguards Initiative to evaluate the IAEA’s long-term budgetary concerns , this paper proposes a series of alternate funding mechanisms that have the potential to sustain the IAEA in the long-term,more » including endowment, charity, and fee-for-service funding models.« less

Automated tracking for advanced satellite laser ranging systems

NASA Astrophysics Data System (ADS)

McGarry, Jan F.; Degnan, John J.; Titterton, Paul J., Sr.; Sweeney, Harold E.; Conklin, Brion P.; Dunn, Peter J.

1996-06-01

NASA's Satellite Laser Ranging Network was originally developed during the 1970's to track satellites carrying corner cube reflectors. Today eight NASA systems, achieving millimeter ranging precision, are part of a global network of more than 40 stations that track 17 international satellites. To meet the tracking demands of a steadily growing satellite constellation within existing resources, NASA is embarking on a major automation program. While manpower on the current systems will be reduced to a single operator, the fully automated SLR2000 system is being designed to operate for months without human intervention. Because SLR2000 must be eyesafe and operate in daylight, tracking is often performed in a low probability of detection and high noise environment. The goal is to automatically select the satellite, setup the tracking and ranging hardware, verify acquisition, and close the tracking loop to optimize data yield. TO accomplish the autotracking tasks, we are investigating (1) improved satellite force models, (2) more frequent updates of orbital ephemerides, (3) lunar laser ranging data processing techniques to distinguish satellite returns from noise, and (4) angular detection and search techniques to acquire the satellite. A Monte Carlo simulator has been developed to allow optimization of the autotracking algorithms by modeling the relevant system errors and then checking performance against system truth. A combination of simulator and preliminary field results will be presented.

Coordinated Research Projects of the IAEA Atomic and Molecular Data Unit

NASA Astrophysics Data System (ADS)

Braams, B. J.; Chung, H.-K.

2011-05-01

The IAEA Atomic and Molecular Data Unit is dedicated to the provision of databases for atomic, molecular and plasma-material interaction (AM/PMI) data that are relevant for nuclear fusion research. IAEA Coordinated Research Projects (CRPs) are the principal mechanism by which the Unit encourages data evaluation and the production of new data. Ongoing and planned CRPs on AM/PMI data are briefly described here.

Design and Fabrication of DebriSat - A Representative LEO Satellite for Improvements to Standard Satellite Breakup Models

NASA Technical Reports Server (NTRS)

Clark, S.; Dietrich, A.; Fitz-Coy, N.; Weremeyer, M.; Liou, J.-C.

2012-01-01

This paper discusses the design and fabrication of DebriSat, a 50 kg satellite developed to be representative of a modern low Earth orbit satellite in terms of its components, materials used, and fabrication procedures. DebriSat will be the target of a future hypervelocity impact experiment to determine the physical characteristics of debris generated after an on-orbit collision of a modern LEO satellite. The major ground-based satellite impact experiment used by DoD and NASA in their development of satellite breakup models was SOCIT, conducted in 1992. The target used for that experiment was a Navy transit satellite (40 cm, 35 kg) fabricated in the 1960's. Modern satellites are very different in materials and construction techniques than those built 40 years ago. Therefore, there is a need to conduct a similar experiment using a modern target satellite to improve the fidelity of the satellite breakup models. To ensure that DebriSat is truly representative of typical LEO missions, a comprehensive study of historical LEO satellite designs and missions within the past 15 years for satellites ranging from 1 kg to 5000 kg was conducted. This study identified modern trends in hardware, material, and construction practices utilized in recent LEO missions. Although DebriSat is an engineering model, specific attention is placed on the quality, type, and quantity of the materials used in its fabrication to ensure the integrity of the outcome. With the exception of software, all other aspects of the satellite s design, fabrication, and assembly integration and testing will be as rigorous as that of an actual flight vehicle. For example, to simulate survivability of launch loads, DebriSat will be subjected to a vibration test. As well, the satellite will undergo thermal vacuum tests to verify that the components and overall systems meet typical environmental standards. Proper assembly and integration techniques will involve comprehensive joint analysis, including the precise

Photometric Study of Uranian Satellites

NASA Technical Reports Server (NTRS)

Kesten, Philip R.

1998-01-01

The best summary of my work at NASA is expressed in the following abstract, submitted the Division for Planetary Science of the American Astronomical Society and to be presented at the annual meeting in Madison in October. We report photometric measurements of Uranian satellites Miranda, Ariel, Umbriel and Titania (10.4 Aug. 1995), and Neptune's satellite Triton (21.2 Sept. 1995) with the infrared camera (IRCAM) and standard J (1.13 - 1.42 microns), H (1.53 - 1.81 microns), and K (2.00 - 2.41 microns) filters at the 3.8-m UKIRT telescope on Mauna Kea. The individual images frames are 256 x 256 pixels with a platescale of .286 arcsec/pixel, resulting in a 1.22 arc min field of view. This summer brought the IR photometry measurements nearly to a close. As indicated by the abstract above, I will present this work at the annual DPS meeting in October. In anticipation of the opening of the new Carl Sagan Laboratory for Cosmochemisty, of which I will be a participating member, I also devoted a considerable fraction of the summer to learning the biochemistry which underlies the experiments to be conducted. To put the end of the summary close to the beginning, it was a most productive summer.

Concept definition study for recovery of tumbling satellites. Volume 2: Supporting research and technology report

NASA Technical Reports Server (NTRS)

Cable, D. A.; Derocher, W. L., Jr.; Cathcart, J. A.; Keeley, M. G.; Madayev, L.; Nguyen, T. K.; Preese, J. R.

1986-01-01

A number of areas of research and laboratory experiments were identified which could lead to development of a cost efficient remote, disable satellite recovery system. Estimates were planned of disabled satellite motion. A concept is defined as a Tumbling Satellite Recovery kit which includes a modular system, composed of a number of subsystem mechanisms that can be readily integrated into varying combinations. This would enable the user to quickly configure a tailored remote, disabled satellite recovery kit to meet a broad spectrum of potential scenarios. The capability was determined of U.S. Earth based satellite tracking facilities to adequately determine the orientation and motion rates of disabled satellites.

TOPEX satellite option study

NASA Technical Reports Server (NTRS)

1982-01-01

The basic design of the fleet satellite communication spacecraft (FLTSATCOM) can easily accommodate any of the three payload options for the ocean dynamic topography experiment (TOPEX). The principal mission requirements as well as the payload accommodations and communications systems needed for launching this payload are reviewed. The existing FLTSATCOM satellite design is identified and the approaches for the proposed propulsion system are described in addition to subsystems for mechanical; power; attitude and velocity control; and telemetry, tracking and control are described. The compatability of FLTSATCOM with the launch vehicle is examined and its capabilities vs TOPEX requirements are summarized. Undetermined changes needed to meet data storage, thermal control, and area to mass ratio requirements are discussed. Cost estimates are included for budgetary and planning purposes. The availability of the described design is assessed based on the continuing production of FLTSATCOM spacecraft during the schedule span planned for TOPEX.

Applications of satellite and marine geodesy to operations in the ocean environment

NASA Technical Reports Server (NTRS)

Fubara, D. M.; Mourad, A. G.

1975-01-01

The requirements for marine and satellite geodesy technology are assessed with emphasis on the development of marine geodesy. Various programs and missions for identification of the satellite geodesy technology applicable to marine geodesy are analyzed along with national and international marine programs to identify the roles of satellite/marine geodesy techniques for meeting the objectives of the programs and other objectives of national interest effectively. The case for marine geodesy is developed based on the extraction of requirements documented by authoritative technical industrial people, professional geodesists, government agency personnel, and applicable technology reports.

A review of satellite time-transfer technology: Accomplishments and future applications

NASA Technical Reports Server (NTRS)

Cooper, R. S.; Chi, A. R.

1978-01-01

The research accomplishments by NASA in meeting the needs of the space program for precise time in satellite tracking are presented. As a major user of precise time signals for clock synchronization of NASA's worldwide satellite tracking networks, the agency provides much of the necessary impetus for the development of stable frequency sources and time synchronization technology. The precision time required for both satellite tracking and space science experiments has increased at a rate of about one order of magnitude per decade from 1 millisecond in the 1950's to 100 microseconds during the Apollo era in the 1960's to 10 microseconds in the 1970's. For the Tracking and Data Relay Satellite System, satellite timing requirements will be extended to 1 microsecond and below. These requirements are needed for spacecraft autonomy and data packeting.

IAEA activities related to radiation biology and health effects of radiation.

PubMed

Wondergem, Jan; Rosenblatt, Eduardo

2012-03-01

The IAEA is involved in capacity building with regard to the radiobiological sciences in its member states through its technical cooperation programme. Research projects/programmes are normally carried out within the framework of coordinated research projects (CRPs). Under this programme, two CRPs have been approved which are relevant to nuclear/radiation accidents: (1) stem cell therapeutics to modify radiation-induced damage to normal tissue, and (2) strengthening biological dosimetry in IAEA member states.

Satellite orbit considerations for a global change technology architecture trade study

NASA Technical Reports Server (NTRS)

Harrison, Edwin F.; Gibson, Gary G.; Suttles, John T.; Buglia, James J.; Taback, Israel

1991-01-01

A study was conducted to determine satellite orbits for earth observation missions aimed at obtaining data for assessing data global climate change. A multisatellite system is required to meet the scientific requirements for temporal coverage over the globe. The best system consists of four sun-synchronous satellites equally spaced in local time of equatorial crossing. This system can obtain data every three hours for all regions. Several other satellite systems consisting of combinations of sun-synchronous orbits and either the Space Station Freedom or a mid-altitude equatorial satellite can provide three to six hour temporal coverage, which is sufficient for measuring many of the parameters required for the global change monitoring mission. Geosynchronous satellites are required to study atmospheric and surface processes involving variations on the order of a few minutes to an hour. One or two geosynchronous satellites can be relocated in longitude to study processes over selected regions of earth.

IIth AMS Conference on Satellite Meteorology and Oceanography.

NASA Astrophysics Data System (ADS)

Velden, Christopher; Digirolamo, Larry; Glackin, Mary; Hawkins, Jeffrey; Jedlovec, Gary; Lee, Thomas; Petty, Grant; Plante, Robert; Reale, Anthony; Zapotocny, John

2002-11-01

The American Meteorological Society (AMS) held its 11th Conference on Satellite Meteorology and Oceanography at the Monona Terrace Convention Center in Madison, Wisconsin, during 15-18 October 2001. The purpose of the conference, typically held every 18 months, is to promote a forum for AMS membership, international scientists, and student members to present and discuss the latest advances in satellite remote sensing for meteorological and oceanographical applications. This year, surrounded by inspirational designs by famed architect Frank Lloyd Wright, the meeting focused on several broad topics related to remote sensing from space, including environmental applications of land and oceanic remote sensing, climatology and long-term satellite data studies, operational applications, radiances and retrievals, and new technology and methods. A vision of an increasing convergence of satellite systems emerged that included operational and research satellite programs and interdisciplinary user groups.The conference also hosted NASA's Electronic Theater, which was presented to groups of middle and high school students totaling over 5500. It was truly a successful public outreach event. The conference banquet was held on the final evening, where a short tribute to satellite pioneer Verner Suomi was given by Joanne Simpson. Suomi was responsible for establishing the Space Science and Engineering Center at the University of Wisconsin in Madison.

Optimizing Satellite Communications With Adaptive and Phased Array Antennas

NASA Technical Reports Server (NTRS)

Ingram, Mary Ann; Romanofsky, Robert; Lee, Richard Q.; Miranda, Felix; Popovic, Zoya; Langley, John; Barott, William C.; Ahmed, M. Usman; Mandl, Dan

2004-01-01

A new adaptive antenna array architecture for low-earth-orbiting satellite ground stations is being investigated. These ground stations are intended to have no moving parts and could potentially be operated in populated areas, where terrestrial interference is likely. The architecture includes multiple, moderately directive phased arrays. The phased arrays, each steered in the approximate direction of the satellite, are adaptively combined to enhance the Signal-to-Noise and Interference-Ratio (SNIR) of the desired satellite. The size of each phased array is to be traded-off with the number of phased arrays, to optimize cost, while meeting a bit-error-rate threshold. Also, two phased array architectures are being prototyped: a spacefed lens array and a reflect-array. If two co-channel satellites are in the field of view of the phased arrays, then multi-user detection techniques may enable simultaneous demodulation of the satellite signals, also known as Space Division Multiple Access (SDMA). We report on Phase I of the project, in which fixed directional elements are adaptively combined in a prototype to demodulate the S-band downlink of the EO-1 satellite, which is part of the New Millennium Program at NASA.

Earth-satellite propagation above GHz: Papers from the 1972 spring URSI session on experiments utilizing the ATS-5 satellite

NASA Technical Reports Server (NTRS)

Ippolito, L. J. (Compiler)

1972-01-01

Papers are reported from the Special Session on Earth-Satellite Propagation Above 10 GHz, presented at The 1972 Spring Meeting of the United States National Committee, International Union of Radio Science, April 1972, Washington, D. C. This session was devoted to propagation measurements associated with the Applications Technology Satellite (ATS-5), which provided the first operational earth-space links at frequencies above 15 GHz. A comprehensive summary is presented of the major results of the ATS-5 experiment measurements and related radiometric, radar and meteorological studies. The papers are organized around seven selected areas of interest, with the results of the various investigators combined into a single paper presented by a principal author for that area. A comprehensive report is provided on the results of the ATS-5 satellite to earth transmissions. A complete list of published reports and presentations related to the ATS-5 Millimeter Wave Experiment is included.

Landsat Science Team: 2016 winter meeting summary

USGS Publications Warehouse

Schroeder, Todd; Loveland, Thomas; Wulder, Michael A.; Irons, James R.

2016-01-01

The winter meeting of the joint U.S. Geological Survey (USGS)–NASA Landsat Science Team (LST) was held January 12-14, 2016, at Virginia Tech University in Blacksburg, VA. LST co-chairs Tom Loveland [USGS’s Earth Resources Observation and Science Data Center (EROS)—Senior Scientist] and Jim Irons [NASA’s Goddard Space Flight Center (GSFC)—Landsat 8 Project Scientist] welcomed more than 50 participants to the three-day meeting. The main objectives of this meeting focused on identifying priorities and approaches to improve the global moderate-resolution satellite record. Overall, the meeting was geared more towards soliciting team member recommendations on several rapidly evolving issues, than on providing updates on individual research activities. All the presentations given at the meeting are available at landsat.usgs. gov//science_LST_january2016.php.

The IAEA neutron coincidence counting (INCC) and the DEMING least-squares fitting programs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krick, M.S.; Harker, W.C.; Rinard, P.M.

1998-12-01

Two computer programs are described: (1) the INCC (IAEA or International Neutron Coincidence Counting) program and (2) the DEMING curve-fitting program. The INCC program is an IAEA version of the Los Alamos NCC (Neutron Coincidence Counting) code. The DEMING program is an upgrade of earlier Windows{reg_sign} and DOS codes with the same name. The versions described are INCC 3.00 and DEMING 1.11. The INCC and DEMING codes provide inspectors with the software support needed to perform calibration and verification measurements with all of the neutron coincidence counting systems used in IAEA inspections for the nondestructive assay of plutonium and uranium.

Training of interventional cardiologists in radiation protection--the IAEA's initiatives.

PubMed

Rehani, Madan M

2007-01-08

The International Atomic Energy Agency (IAEA) has initiated a major international initiative to train interventional cardiologists in radiation protection as a part of its International Action Plan on the radiological protection of patients. A simple programme of two days' training has been developed, covering possible and observed radiation effects among patients and staff, international standards, dose management techniques, examples of good and bad practice and examples indicating prevention of possible injuries as a result of good practice of radiation protection. The training material is freely available on CD from the IAEA. The IAEA has conducted two events in 2004 and 2005 and number of events are planned in 2006. The survey conducted among the cardiologists participating in these programmes indicates that over 80% of them were attending such a structured programme on radiation protection for the first time. As the magnitude of X-ray usage in cardiology grows to match that in interventional radiology, the standards of training on radiation effects, radiation physics and radiation protection in interventional cardiology should also match those in interventional radiology.

A Viking satellite orbit trim strategy

NASA Technical Reports Server (NTRS)

Hintz, G. R.

1971-01-01

One strategy is submitted for meeting the varied and stringent requirements of the Viking Project on the control of the satellite orbit to obtain reconnaissance and to prepare for lander release. To satisfy these requirements, different orbit trim maneuver strategies were developed for two typical Viking missions. In addition, a summary of recent numerical results is included to show that this strategy satisfies the mission requirements which have been identified.

Two-Way Satellite Time and Frequency Transfer (TWSTFT) Calibration Constancy From Closure Sums

DTIC Science & Technology

2008-12-01

40th Annual Precise Time and Time Interval (PTTI) Meeting 587 TWO-WAY SATELLITE TIME AND FREQUENCY TRANSFER ( TWSTFT ) CALIBRATION...Paris, France Abstract Two-way Satellite Time and Frequency Transfer ( TWSTFT ) is considered to be the most accurate means of long-distance...explanations for small, but non-zero, biases observed in the closure sums of uncalibrated data are presented. I. INTRODUCTION TWSTFT [1] has

The U.S./IAEA Workshop on Software Sustainability for Safeguards Instrumentation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pepper S. E.; .; Worrall, L.

2014-08-08

The U.S. National Nuclear Security Administration’s Next Generation Safeguards Initiative, the U.S. Department of State, and the International Atomic Energy Agency (IAEA) organized a a workshop on the subject of ”Software Sustainability for Safeguards Instrumentation.” The workshop was held at the Vienna International Centre in Vienna, Austria, May 6-8, 2014. The workshop participants included software and hardware experts from national laboratories, industry, government, and IAEA member states who were specially selected by the workshop organizers based on their experience with software that is developed for the control and operation of safeguards instrumentation. The workshop included presentations, to orient the participantsmore » to the IAEA Department of Safeguards software activities related to instrumentation data collection and processing, and case studies that were designed to inspire discussion of software development, use, maintenance, and upgrades in breakout sessions and to result in recommendations for effective software practices and management. This report summarizes the results of the workshop.« less

University Satellite Consortium and Space Education in Japan Centered on Micro-Nano Satellites

NASA Astrophysics Data System (ADS)

Nakasuka, S.; Kawashima, R.

2002-01-01

the space development. activities, including how to acquire frequency permission, how to obtain launch opportunity and financial support, how to operate the launched satellites using cheap ground stations, etc. Especially, the frequency problem should be solved as soon as possible because so many universities in the world are planning similar projects and the frequency in the amateur band are already very congested. One idea is that universities should make a world wide "university satellite community" and collaboratively ask for a kind of "Educational frequency" to ITU, and share the obtained frequency within the community under the community's own management. This kind of community will also be useful for collaborative satellite operation, because the universities which have a ground station spread over the world. I hope the IAC meeting will provide a good opportunity for discussing these problems and facilitating the construction of world wide university community to tackle with these problems.

INMARSAT - The International Maritime Satellite Organization: Origins and structure

NASA Technical Reports Server (NTRS)

Doyle, S. E.

1977-01-01

The third session of the International Conference on the Establishment of an International Maritime Satellite System established the International Maritime Satellite Organization (INMARSAT) in 1976. Its main functions are to improve maritime communications via satellite, thereby facilitating more efficient emergency communications, ship management, and maritime public correspondence services. INMARSAT's aims are similar to those of the Intergovernmental Maritime Consultative Organization (IMCO), the main United Nations organization dealing with maritime affairs. The specific functions of INMARSAT have been established by an Intersessional Working Group (IWG) which met three times between general conference meetings. Initial investment shares for the creation of INMARSAT were shared by the United States (17%), the United Kingdom (12%), the U.S.S.R. (11%), Norway (9.50%), Japan (8.45%), Italy (4.37%), and France (3.50%).

Central Satellite Data Repository Supporting Research and Development

NASA Astrophysics Data System (ADS)

Han, W.; Brust, J.

2015-12-01

Near real-time satellite data is critical to many research and development activities of atmosphere, land, and ocean processes. Acquiring and managing huge volumes of satellite data without (or with less) latency in an organization is always a challenge in the big data age. An organization level data repository is a practical solution to meeting this challenge. The STAR (Center for Satellite Applications and Research of NOAA) Central Data Repository (SCDR) is a scalable, stable, and reliable repository to acquire, manipulate, and disseminate various types of satellite data in an effective and efficient manner. SCDR collects more than 200 data products, which are commonly used by multiple groups in STAR, from NOAA, GOES, Metop, Suomi NPP, Sentinel, Himawari, and other satellites. The processes of acquisition, recording, retrieval, organization, and dissemination are performed in parallel. Multiple data access interfaces, like FTP, FTPS, HTTP, HTTPS, and RESTful, are supported in the SCDR to obtain satellite data from their providers through high speed internet. The original satellite data in various raster formats can be parsed in the respective adapter to retrieve data information. The data information is ingested to the corresponding partitioned tables in the central database. All files are distributed equally on the Network File System (NFS) disks to balance the disk load. SCDR provides consistent interfaces (including Perl utility, portal, and RESTful Web service) to locate files of interest easily and quickly and access them directly by over 200 compute servers via NFS. SCDR greatly improves collection and integration of near real-time satellite data, addresses satellite data requirements of scientists and researchers, and facilitates their primary research and development activities.

Communications to 2000 - A forecast of the demand and capacity of U.S. domestic communications satellites

NASA Astrophysics Data System (ADS)

Fordyce, S. W.

The market demand for the U.S. domestic communications satellites accelerated in the late 70's, exceeding the capacity of the satellites currently in orbit. Satellite carriers have been authorized to build an additional 24 domsats. This paper examines the anticipated market demands, and the capability of the domsats to fulfill these demands. With various practical technical innovations, the domsats appear able to meet the expected market demands until the end of this century.

Report on the ESO Workshop ''Satellites and Streams in Santiago''

NASA Astrophysics Data System (ADS)

Küpper, A. H. W.; Mieske, S.

2015-09-01

Galactic satellites and tidal streams are arguably the two most direct imprints of hierarchical structure formation in the haloes of galaxies. At this ESO workshop we sought to create the big picture of the galactic accretion process, and shed light on the interplay between satellites and streams in the Milky Way, Andromeda and beyond. The Scientific Organising Committee prepared a well-balanced programme with 60 talks and 30 poster contributions, resulting in a meeting which was greatly enjoyed by the more than 110 participants at the venue, and worldwide via Twitter (#SSS15).

A review of satellite time transfer technology - Accomplishments and future applications

NASA Technical Reports Server (NTRS)

Cooper, R. S.; Chi, A. R.

1979-01-01

A brief review of the research accomplishments by NASA in meeting the needs of the space program for precise time in satellite tracking is presented. As a major user of precise time signals for clock synchronization of NASA's worldwide satellite tracking networks, the agency provided much of the necessary impetus for the development of stable frequency sources and time synchronization technology. The precision in time required for both satellite tracking and space science experiments has increased at a rate of about 1 order of magnitude per decade from 1 ms in the 1950's to 100 microsec during the Apollo era in the 1960's to 10 microsec in the 1970's. In the 1980's, when the Tracking and Data Relay Satellite System (TDRSS) comes into operation, satellite timing requirements will be extended to 1 microsec and below. These requirements are needed for spacecraft autonomy and data packeting which are now in active planning stages.

Videoconferencing Via Satellite: Opening Congress to the People. Technical Report.

ERIC Educational Resources Information Center

Wood, Fred B.; And Others

The value of satellite videoconferencing in providing a new mechanism for informed dialogue between congressmen and constituents is evaluated through actual demonstrations. The experimental demonstrations described include large and small group congressional-constituent meetings in urban and rural areas, and a congressional subcommittee hearing…

Contribution to fusion research from IAEA coordinated research projects and joint experiments

NASA Astrophysics Data System (ADS)

Gryaznevich, M.; Van Oost, G.; Stöckel, J.; Kamendje, R.; Kuteev, B. N.; Melnikov, A.; Popov, T.; Svoboda, V.; The IAEA CRP Teams

2015-10-01

The paper presents objectives and activities of IAEA Coordinated Research Projects ‘Conceptual development of steady-state compact fusion neutron sources’ and ‘Utilisation of a network of small magnetic confinement fusion devices for mainstream fusion research’. The background and main projects of the CRP on FNS are described in detail, as this is a new activity at IAEA. Recent activities of the second CRP, which continues activities of previous CRPs, are overviewed.

Analysis of historical delta values for IAEA/LANL NDA training courses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geist, William; Santi, Peter; Swinhoe, Martyn

2009-01-01

The Los Alamos National Laboratory (LANL) supports the International Atomic Energy Agency (IAEA) by providing training for IAEA inspectors in neutron and gamma-ray Nondestructive Assay (NDA) of nuclear material. Since 1980, all new IAEA inspectors attend this two week course at LANL gaining hands-on experience in the application of NDA techniques, procedures and analysis to measure plutonium and uranium nuclear material standards with well known pedigrees. As part of the course the inspectors conduct an inventory verification exercise. This exercise provides inspectors the opportunity to test their abilities in performing verification measurements using the various NDA techniques. For an inspector,more » the verification of an item is nominally based on whether the measured assay value agrees with the declared value to within three times the historical delta value. The historical delta value represents the average difference between measured and declared values from previous measurements taken on similar material with the same measurement technology. If the measurement falls outside a limit of three times the historical delta value, the declaration is not verified. This paper uses measurement data from five years of IAEA courses to calculate a historical delta for five non-destructive assay methods: Gamma-ray Enrichment, Gamma-ray Plutonium Isotopics, Passive Neutron Coincidence Counting, Active Neutron Coincidence Counting and the Neutron Coincidence Collar. These historical deltas provide information as to the precision and accuracy of these measurement techniques under realistic conditions.« less

Should Non Department of Defense Meteorological Satellites Be Used to Meet Department of Defense Environmental Requirements?

DTIC Science & Technology

2003-06-06

Information Support laboratory, Geostationary Operational Meteorological Satellite. (Moscow, RU: SMIS IKI RAN and SRC PLANETA , January 2003); Internet...Operational Meteorological Satellite. Moscow, RU: SMIS IKI RAN and SRC PLANETA , January 2003. Squitieri, Tom. “In Bosnia, Weather is primary Foe”. USA Today

INF and IAEA: A comparative analysis of verification strategy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scheinman, L.; Kratzer, M.

1992-07-01

This is the final report of a study on the relevance and possible lessons of Intermediate Range Nuclear Force (INF) verification to the International Atomic Energy Agency (IAEA) international safeguards activities.

Exploring Modular Architecture for Nano Satellite and Opportunity for Developing Countries

NASA Astrophysics Data System (ADS)

Rhaman, M. K.; Monowar, M. I.; Shakil, S. R.; Kafi, A. H.; Antara, R. S. I.

2015-01-01

SPACE Technology has the potential to provide information, infrastructure and inspiration that meets national needs in developing countries like Bangladesh. Many countries recognize this; in response they are investing in new national satellite programs to harness satellite services. Technology related to space is one example of a tool that can contribute to development both by addressing societal challenges and by advancing a nation's technological capability. To cope up with the advanced world in space technology Bangladesh seems to be highly potential country for satellite, Robotics, embedded systems and renewable energy research. BRAC University, Bangladesh is planning to launch a nano satellite with the collaboration of KIT, Japan. The proposed nano satellite project mission is to experiment about social, commercial and agricultural survey needs in Bangladesh. Each of the proposed applications of the project will improve the lives of millions of people of Bangladesh and it will be a pathfinder mission for the people of this country. Another intention of this project is to create a cheap satellite based remote sensing for developing countries as the idea of large space systems is very costly for us therefore we have decided to make a Nano-satellite.

Feasibility of satellite interferometry for surveillance, navigation, and traffic control

NASA Technical Reports Server (NTRS)

Gopalapillai, S.; Ruck, G. T.; Mourad, A. G.

1976-01-01

The feasibility of using a satellite borne interferometry system for surveillance, navigation, and traffic control applications was investigated. The evaluation was comprised of: (1) a two part systems analysis (software and hardware); (2) a survey of competitive navigation systems (both experimental and planned); (3) a comparison of their characteristics and capabilities with those of an interferometry system; and (4) a limited survey of potential users to determine the variety of possible applications for the interferometry system and the requirements which it would have to meet. Five candidate or "strawman" interferometry systems for various applications with various capabilities were configured (on a preliminary basis) and were evaluated. It is concluded that interferometry in conjunction with a geostationary satellite has an inherent ability to provide both a means for navigation/position location and communication. It offers a very high potential for meeting a large number of user applications and requirements for navigation and related functions.

Organizing Scientific Meetings

NASA Astrophysics Data System (ADS)

Epple, August

1997-03-01

Preface; 1. Introduction: What can go wrong?; 2. The decision: To run or not to run; 3. Scientific and related events: variety delights; 4. Social events: something for every taste and budget; 5. The program: how to accommodate pigs in a poke; 6. Selection of the meeting site: a touch of Russian roulette; 7. The dates of the meeting: you can't win; 8. Publications: cruel and unusual punishment; 9. Selection of participants: how to lose old friends and make new enemies; 10. Committees: you have to live with them; 11. Accompanists: you better love'm; 12. Office and staff: don't take chances; 13. The budget: a jungle with pitfalls; 14. Fund raising: some would rather see their dentist; 15. Allocation of travel support: not much fun either; 16. Schedule of preparations: from dream to reality; 17. Announcements and other information: clarity pays; 18. Design of forms, name tags, tickets, signs and stickers: how about using some common sense?; 19. Satellite meetings: think twice; 20. Checklist of important no-nos; List of appendixes; Appendixes A-R; Index.

Minutes of the Sixth CEOS Plenary Meeting

NASA Technical Reports Server (NTRS)

1993-01-01

The Committee on Earth Observations Satellites (CEOS) minutes for the sixth plenary meeting held in London, December 9-11, 1992 are presented. Attending as prospective members were the Russian Space Agency (RSA), the Committee for Hydrometeorology and Environmental Monitoring of the Ministry for Ecology and Natural resources of the Russian Federation (ROSCOMGIDROMET), the Chinese Academy of Space Technology (CAST) and the National Remote Sensing Center of China (NRSCC). Actions taken at the meeting included membership issues, CEOS proposals, data policy, and working group reports. Data requirements of CEOS affiliates were also reported on. Additional summations and statements as well as lists of participants and future meetings are included. In general, topics covered related to remote sensing and global change.

The sixth conference on satellite meteorology and oceanography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hauth, F.F.; Purdom, J.F.W.

The Sixth Conference on Satellite Meteorology and Oceanography was held in conjunction with the AMS Annual Meeting in Atlanta, Georgia, the week of 6 January 1992. Over 150 scientific papers were presented orally or in poster sessions. Joint sessions were held with the Symposium on Weather Forecasting and the Eighth International Conference on Interactive Information and Processing Systems for Meteorology, Oceanography, and Hydrology. The quality of the papers in the preprint volume, as well as in the presentations at both oral and poster sessions, reflects the robustness of national and international operational and research interests in satellite meteorology and oceanography.more » A preprint volume for this conference is available through the AMS.« less

77 FR 30542 - Notice of a Public Meeting To Prepare for the Twenty-Second Session of the Assembly of the...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-23

... To Prepare for the Twenty-Second Session of the Assembly of the International Mobile Satellite... the Assembly of the International Mobile Satellite Organization (IMSO). DATES: A public meeting will... International Mobile Satellite Organization (IMSO) Assembly to be held June 25-28, 2012 in London, United...

Current developments in electrochemical storage systems for satellites

NASA Technical Reports Server (NTRS)

Gutmann, G.

1986-01-01

The need for batteries with greater power capacity and service life for power satellites is examined. The Ni/Cd and Ni/H batteries now being used must be upgraded to meet advanced space requirements. Improvements in power capacity, service life, and cycle count for various satellites in LEO and GEO orbits are discussed. The Ni/Cd and Ni/H cell reactions are explained, and the solubility and volume changes for various charged and uncharged masses are described. A chart of the energy content and cycle count for various cell systems is presented, and the factors which cause aging and failure in the Ni/Cd and Ni/H cell systems are discussed. The advantages of the Ni/H battery are given and the need for more developed electrochemical storage systems because of an increase in the mass of satellites is explained. The requirements for space batteries and the work currently done by NASA and West Germany on advanced batteries are discussed.

Testing the methodology for dosimetry audit of heterogeneity corrections and small MLC-shaped fields: Results of IAEA multi-center studies.

PubMed

Izewska, Joanna; Wesolowska, Paulina; Azangwe, Godfrey; Followill, David S; Thwaites, David I; Arib, Mehenna; Stefanic, Amalia; Viegas, Claudio; Suming, Luo; Ekendahl, Daniela; Bulski, Wojciech; Georg, Dietmar

2016-07-01

The International Atomic Energy Agency (IAEA) has a long tradition of supporting development of methodologies for national networks providing quality audits in radiotherapy. A series of co-ordinated research projects (CRPs) has been conducted by the IAEA since 1995 assisting national external audit groups developing national audit programs. The CRP 'Development of Quality Audits for Radiotherapy Dosimetry for Complex Treatment Techniques' was conducted in 2009-2012 as an extension of previously developed audit programs. The CRP work described in this paper focused on developing and testing two steps of dosimetry audit: verification of heterogeneity corrections, and treatment planning system (TPS) modeling of small MLC fields, which are important for the initial stages of complex radiation treatments, such as IMRT. The project involved development of a new solid slab phantom with heterogeneities containing special measurement inserts for thermoluminescent dosimeters (TLD) and radiochromic films. The phantom and the audit methodology has been developed at the IAEA and tested in multi-center studies involving the CRP participants. The results of multi-center testing of methodology for two steps of dosimetry audit show that the design of audit procedures is adequate and the methodology is feasible for meeting the audit objectives. A total of 97% TLD results in heterogeneity situations obtained in the study were within 3% and all results within 5% agreement with the TPS predicted doses. In contrast, only 64% small beam profiles were within 3 mm agreement between the TPS calculated and film measured doses. Film dosimetry results have highlighted some limitations in TPS modeling of small beam profiles in the direction of MLC leave movements. Through multi-center testing, any challenges or difficulties in the proposed audit methodology were identified, and the methodology improved. Using the experience of these studies, the participants could incorporate the auditing

Ocean observer study: A proposed national asset to augment the future U.S. operational satellite system

USGS Publications Warehouse

Cunningham, J.D.; Chambers, D.; Davis, C.O.; Gerber, A.; Helz, R.; McGuire, J.P.; Pichel, W.

2003-01-01

The next generation of U.S. polar orbiting environmental satellites, are now under development. These satellites, jointly developed by the Department of Defense (DoD), the Department of Commerce (DOC), and the National Aeronautics and Space Administration (NASA), will be known as the National Polar-orbiting Operational Environmental Satellite System (NPOESS). It is expected that the first of these satellites will be launched in 2010. NPOESS has been designed to meet the operational needs of the U.S. civilian meteorological, environmental, climatic, and space environmental remote sensing programs, and the Global Military Space and Geophysical Environmental remote sewing programs. This system, however, did not meet all the needs of the user community interested in operational oceanography (particularly in coastal regions). Beginning in the fall of 2000, the Integrated Program Office (IPO), a joint DoD, DOC, and NASA office responsible for the NPOESS development, initiated the Ocean Observer Study (OOS). The purpose of this study was to assess and recommend how best to measure the missing or inadequately sampled ocean parameters. This paper summarizes the ocean measurement requirements documented in the OOS, describes the national need to measure these parameters, and describes the satellite instrumentation required to make those measurements.

Trends in NASA communication satellites.

NASA Technical Reports Server (NTRS)

Sivo, J. N.; Robbins, W. H.; Stretchberry, D. M.

1972-01-01

Discussion of the potential applications of satellite communications technology in meeting the national needs in education, health care, culture, and data transfer techniques. Experiments with the NASA ATS 1, 3 and 5 spacecraft, which are conducted in an attempt to satisfy such needs, are reviewed. The future needs are also considered, covering the requirements of multiple region coverage, communications between regions, large numbers of ground terminals, multichannel capability and high quality TV pictures. The ATS F and CTS spacecraft are expected to be available in the near future to expand experiments in this field.

IAEA Nuclear Data Section: provision of atomic and nuclear databases for user applications.

PubMed

Humbert, Denis P; Nichols, Alan L; Schwerer, Otto

2004-01-01

The Nuclear Data Section (NDS) of the International Atomic Energy Agency (IAEA) provides a wide range of atomic and nuclear data services to scientists worldwide, with particular emphasis placed on the needs of developing countries. Highly focused Co-ordinated Research Projects and multinational data networks are sponsored under the auspices of the IAEA for the development and assembly of databases through the organised participation of specialists from Member States. More than 100 data libraries are readily available cost-free through the Internet, CD-ROM and other media. These databases are used in a wide range of applications, including fission- and fusion-energy, non-energy applications and basic research studies. Further information concerning the various services can be found through the web address of the IAEA Nuclear Data Section: and a mirror site at IPEN, Brazil that is maintained by NDS staff:.

Calibrated sulfur isotope abundance ratios of three IAEA sulfur isotope reference materials and V-CDT with a reassessment of the atomic weight of sulfur

NASA Astrophysics Data System (ADS)

Ding, T.; Valkiers, S.; Kipphardt, H.; De Bièvre, P.; Taylor, P. D. P.; Gonfiantini, R.; Krouse, R.

2001-08-01

Calibrated values have been obtained for sulfur isotope abundance ratios of sulfur isotope reference materials distributed by the IAEA (Vienna). For the calibration of the measurements, a set of synthetic isotope mixtures were prepared gravimetrically from high purity Ag2S materials enriched in32S, 33S, and 34S. All materials were converted into SF6 gas and subsequently, their sulfur isotope ratios were measured on the SF5+ species using a special gas source mass spectrometer equipped with a molecular flow inlet system (IRMM's Avogadro II amount comparator). Values for the 32S/34S abundance ratios are 22.650 4(20), 22.142 4(20), and 23.393 3(17) for IAEA-S-1, IAEA-S-2, and IAEA-S-3, respectively. The calculated 32S/34S abundance ratio for V-CDT is 22.643 6(20), which is very close to the calibrated ratio obtained by Ding et al. (1999). In this way, the zero point of the VCDT scale is anchored firmly to the international system of units SI. The 32S/33S abundance ratios are 126.942(47), 125.473(55), 129.072(32), and 126.948(47) for IAEA-S-1, IAEA-S-2, IAEA-S-3, and V-CDT, respectively. In this way, the linearity of the V-CDT scale is improved over this range. The values of the sulfur molar mass for IAEA-S-1 and V-CDT were calculated to be 32.063 877(56) and 32.063 911(56), respectively, the values with the smallest combined uncertainty ever reported for the sulfur molar masses (atomic weights).

A standard satellite control reference model

NASA Technical Reports Server (NTRS)

Golden, Constance

1994-01-01

This paper describes a Satellite Control Reference Model that provides the basis for an approach to identify where standards would be beneficial in supporting space operations functions. The background and context for the development of the model and the approach are described. A process for using this reference model to trace top level interoperability directives to specific sets of engineering interface standards that must be implemented to meet these directives is discussed. Issues in developing a 'universal' reference model are also identified.

Proficiency Testing as a tool to monitor consistency of measurements in the IAEA/WHO Network of Secondary Standards Dosimetry Laboratories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meghzifene, Ahmed; Czap, Ladislav; Shortt, Ken

2008-08-14

The International Atomic Energy Agency (IAEA) and the World Health Organization (WHO) established a Network of Secondary Standards Dosimetry Laboratories (IAEA/WHO SSDL Network) in 1976. Through SSDLs designated by Member States, the Network provides a direct link of national dosimetry standards to the international measurement system of standards traceable to the Bureau International des Poids et Mesures (BIPM). Within this structure and through the proper calibration of field instruments, the SSDLs disseminate S.I. quantities and units.To ensure that the services provided by SSDL members to end-users follow internationally accepted standards, the IAEA has set up two different comparison programmes. Onemore » programme relies on the IAEA/WHO postal TLD service and the other uses comparisons of calibrated ionization chambers to help the SSDLs verify the integrity of their national standards and the procedures used for the transfer of the standards to the end-users. The IAEA comparisons include {sup 60}Co air kerma (N{sub K}) and absorbed dose to water (N{sub D,W}) coefficients. The results of the comparisons are confidential and are communicated only to the participants. This is to encourage participation of the laboratories and their full cooperation in the reconciliation of any discrepancy.This work describes the results of the IAEA programme comparing calibration coefficients for radiotherapy dosimetry, using ionization chambers. In this programme, ionization chambers that belong to the SSDLs are calibrated sequentially at the SSDL, at the IAEA, and again at the SSDL. As part of its own quality assurance programme, the IAEA has participated in several regional comparisons organized by Regional Metrology Organizations.The results of the IAEA comparison programme show that the majority of SSDLs are capable of providing calibrations that fall inside the acceptance level of 1.5% compared to the IAEA.« less

Small astronomy satellite-A, Uhuru data analysis

NASA Technical Reports Server (NTRS)

Koch, D.

1974-01-01

Objectives were to conduct observations with the first satellite entirely devoted to X-ray astronomy and to analyze the results obtained. A catalog of X-ray sources was generated, and results of discoveries and further detailed observations of sources were presented in scientific journals and meetings. A list of how objectives were met, a brief description of the instrument, significant results, the X-ray catalog, and a complete bibliography of results are included.

Air traffic management system design using satellite based geo-positioning and communications assets

NASA Technical Reports Server (NTRS)

Horkin, Phil

1995-01-01

The current FAA and ICAO FANS vision of Air Traffic Management will transition the functions of Communications, Navigation, and Surveillance to satellite based assets in the 21st century. Fundamental to widespread acceptance of this vision is a geo-positioning system that can provide worldwide access with best case differential GPS performance, but without the associated problems. A robust communications capability linking-up aircraft and towers to meet the voice and data requirements is also essential. The current GPS constellation does not provide continuous global coverage with a sufficient number of satellites to meet the precision landing requirements as set by the world community. Periodic loss of the minimum number of satellites in view creates an integrity problem, which prevents GPS from becoming the primary system for navigation. Furthermore, there is reluctance on the part of many countries to depend on assets like GPS and GLONASS which are controlled by military communities. This paper addresses these concerns and provides a system solving the key issues associated with navigation, automatic dependent surveillance, and flexible communications. It contains an independent GPS-like navigation system with 27 satellites providing global coverage with a minimum of six in view at all times. Robust communications is provided by a network of TDMA/FDMA communications payloads contained on these satellites. This network can support simultaneous communications for up to 30,000 links, nearly enough to simultaneously support three times the current global fleet of jumbo air passenger aircraft. All of the required hardware is directly traceable to existing designs.

The SAGA Survey. I. Satellite Galaxy Populations around Eight Milky Way Analogs

NASA Astrophysics Data System (ADS)

Geha, Marla; Wechsler, Risa H.; Mao, Yao-Yuan; Tollerud, Erik J.; Weiner, Benjamin; Bernstein, Rebecca; Hoyle, Ben; Marchi, Sebastian; Marshall, Phil J.; Muñoz, Ricardo; Lu, Yu

2017-09-01

We present the survey strategy and early results of the “Satellites Around Galactic Analogs” (SAGA) Survey. The SAGA Survey’s goal is to measure the distribution of satellite galaxies around 100 systems analogous to the Milky Way down to the luminosity of the Leo I dwarf galaxy ({M}r< -12.3). We define a Milky Way analog based on K-band luminosity and local environment. Here, we present satellite luminosity functions for eight Milky-Way-analog galaxies between 20 and 40 Mpc. These systems have nearly complete spectroscopic coverage of candidate satellites within the projected host virial radius down to {r}o< 20.75 using low-redshift gri color criteria. We have discovered a total of 25 new satellite galaxies: 14 new satellite galaxies meet our formal criteria around our complete host systems, plus 11 additional satellites in either incompletely surveyed hosts or below our formal magnitude limit. Combined with 13 previously known satellites, there are a total of 27 satellites around 8 complete Milky-Way-analog hosts. We find a wide distribution in the number of satellites per host, from 1 to 9, in the luminosity range for which there are 5 Milky Way satellites. Standard abundance matching extrapolated from higher luminosities predicts less scatter between hosts and a steeper luminosity function slope than observed. We find that the majority of satellites (26 of 27) are star-forming. These early results indicate that the Milky Way has a different satellite population than typical in our sample, potentially changing the physical interpretation of measurements based only on the Milky Way’s satellite galaxies.

The 1998 Australian external beam radiotherapy survey and IAEA/WHO TLD postal dose quality audit.

PubMed

Huntley, R; Izewska, J

2000-03-01

The results of an updated Australian survey of external beam radiotherapy centres are presented. Most of the centres provided most of the requested information. The relative caseloads of various linear accelerator photon and electron beams have not changed significantly since the previous survey in 1995. The mean age of Australian LINACs is 7.1 years and that of other radiotherapy machines is 14.7 years. Every Australian radiotherapy centre participated in a special run of the IAEA/WHO TLD postal dose quality audit program, which was provided for Australian centres by the IAEA and WHO in May 1998. The dose quoted by the centres was in nearly every case within 1.5% of the dose assessed by the IAEA. This is within the combined standard uncertainty of the IAEA TLD service (1.8%). The results confirm the accuracy and precision of radiotherapy dosimetry in Australia and the adequate dissemination of the Australian standards from ARL (now ARPANSA) to the centres. The Australian standards have recently been shown to agree with those of other countries to within 0.25% by comparison with the BIPM.

Point- and line-based transformation models for high resolution satellite image rectification

NASA Astrophysics Data System (ADS)

Abd Elrahman, Ahmed Mohamed Shaker

Rigorous mathematical models with the aid of satellite ephemeris data can present the relationship between the satellite image space and the object space. With government funded satellites, access to calibration and ephemeris data has allowed the development and use of these models. However, for commercial high-resolution satellites, which have been recently launched, these data are withheld from users, and therefore alternative empirical models should be used. In general, the existing empirical models are based on the use of control points and involve linking points in the image space and the corresponding points in the object space. But the lack of control points in some remote areas and the questionable accuracy of the identified discrete conjugate points provide a catalyst for the development of algorithms based on features other than control points. This research, concerned with image rectification and 3D geo-positioning determination using High-Resolution Satellite Imagery (HRSI), has two major objectives. First, the effects of satellite sensor characteristics, number of ground control points (GCPs), and terrain elevation variations on the performance of several point based empirical models are studied. Second, a new mathematical model, using only linear features as control features, or linear features with a minimum number of GCPs, is developed. To meet the first objective, several experiments for different satellites such as Ikonos, QuickBird, and IRS-1D have been conducted using different point based empirical models. Various data sets covering different terrain types are presented and results from representative sets of the experiments are shown and analyzed. The results demonstrate the effectiveness and the superiority of these models under certain conditions. From the results obtained, several alternatives to circumvent the effects of the satellite sensor characteristics, the number of GCPs, and the terrain elevation variations are introduced. To meet

Exploratory Meeting on Atmospheric Electricity and Severe Storms

NASA Technical Reports Server (NTRS)

Vaughan, W. W. (Editor)

1978-01-01

The meeting was arranged to discuss atmospheric electricity and its relationship to severe storms, the feasibility of developing a set of instruments for either a Space Shuttle or an unmanned satellite, and the scientific rationale which would warrant further in-depth assessment, involvement and development of supporting activities by NASA.

42 CFR 412.534 - Special payment provisions for long-term care hospitals within hospitals and satellites of long...

Code of Federal Regulations, 2010 CFR

2010-10-01

... meets the criteria of § 412.22(h) from another hospital that is not the co-located hospital are made... hospital satellite facility from the co-located hospital are made under either of the following: (1) For... percent were admitted to the hospital or its satellite facility from the co-located hospital, payments are...

Space Power for Communication Satellites Beyond 1995

NASA Technical Reports Server (NTRS)

Pierce, P. R.

1984-01-01

The space power trends for communication satellites beginning in the mid-70's are reviewed. Predictions of technology advancements and requirements were compared with actual growth patterns. The conclusions derived suggest that the spacecraft power system technology base and present rate of advancement will not be able to meet the power demands of the early to mid-90's. It is recommended that an emphasis on accelerating the technology development be made to minimize the technology gap.

The applications of satellites to communications, navigation and surveillance for aircraft operating over the contiguous United States

NASA Technical Reports Server (NTRS)

Craigie, J. H.; Otten, D. D.; Garabedian, A.; Morrison, D. D.; MALLINCKRODT; ZIPPER

1970-01-01

The objective was to determine on a priority basis the satellite applications to communications, navigation, and surveillance requirements for aircraft operating beyond 1975 over the contiguous United States and adjacent oceanic transition regions, and to determine if and how satellite technology can meet these requirements in a reliable, efficient, and economical manner. Major results and conclusions are as follows: (1) The satellite applications of greatest importance are surveillance and rapid collision warning communications; and (2) The necessary technology is available as demonstrated by an attractive system concept.

An IAEA multi-technique X-ray spectrometry endstation at Elettra Sincrotrone Trieste: benchmarking results and interdisciplinary applications.

PubMed

Karydas, Andreas Germanos; Czyzycki, Mateusz; Leani, Juan José; Migliori, Alessandro; Osan, Janos; Bogovac, Mladen; Wrobel, Pawel; Vakula, Nikita; Padilla-Alvarez, Roman; Menk, Ralf Hendrik; Gol, Maryam Ghahremani; Antonelli, Matias; Tiwari, Manoj K; Caliri, Claudia; Vogel-Mikuš, Katarina; Darby, Iain; Kaiser, Ralf Bernd

2018-01-01

The International Atomic Energy Agency (IAEA) jointly with the Elettra Sincrotrone Trieste (EST) operates a multipurpose X-ray spectrometry endstation at the X-ray Fluorescence beamline (10.1L). The facility has been available to external users since the beginning of 2015 through the peer-review process of EST. Using this collaboration framework, the IAEA supports and promotes synchrotron-radiation-based research and training activities for various research groups from the IAEA Member States, especially those who have limited previous experience and resources to access a synchrotron radiation facility. This paper aims to provide a broad overview about various analytical capabilities, intrinsic features and performance figures of the IAEA X-ray spectrometry endstation through the measured results. The IAEA-EST endstation works with monochromatic X-rays in the energy range 3.7-14 keV for the Elettra storage ring operating at 2.0 or 2.4 GeV electron energy. It offers a combination of different advanced analytical probes, e.g. X-ray reflectivity, X-ray absorption fine-structure measurements, grazing-incidence X-ray fluorescence measurements, using different excitation and detection geometries, and thereby supports a comprehensive characterization for different kinds of nanostructured and bulk materials.

Improving Aerosol and Visibility Forecasting Capabilities Using Current and Future Generations of Satellite Observations

DTIC Science & Technology

2013-09-30

forcing through an ensemble-based method. The results of our findings were presented at the 2013 American Meteorological Society (AMS) annual meeting...Forcing to the Existing Satellite Observations, 93rd American Meteorological Society Annual Meeting, Austin, Texas, January 5-10, 2013b...Ceburnis, D., Chang, R., Clarke, A., de Leeuw, G., Deane, G., DeMott, P. J., Elliot, S., Facchini, M. C., Fairall, C. W., Hawkins, L., Hu, Y., Hudson , J

Testing the validity of the International Atomic Energy Agency (IAEA) safety culture model.

PubMed

López de Castro, Borja; Gracia, Francisco J; Peiró, José M; Pietrantoni, Luca; Hernández, Ana

2013-11-01

This paper takes the first steps to empirically validate the widely used model of safety culture of the International Atomic Energy Agency (IAEA), composed of five dimensions, further specified by 37 attributes. To do so, three independent and complementary studies are presented. First, 290 students serve to collect evidence about the face validity of the model. Second, 48 experts in organizational behavior judge its content validity. And third, 468 workers in a Spanish nuclear power plant help to reveal how closely the theoretical five-dimensional model can be replicated. Our findings suggest that several attributes of the model may not be related to their corresponding dimensions. According to our results, a one-dimensional structure fits the data better than the five dimensions proposed by the IAEA. Moreover, the IAEA model, as it stands, seems to have rather moderate content validity and low face validity. Practical implications for researchers and practitioners are included. Copyright © 2013 Elsevier Ltd. All rights reserved.

Satellite images for land cover monitoring - Navigating through the maze

USGS Publications Warehouse

Künzer, Claudia; Fosnight, Gene

2001-01-01

The focus of this publication is satellite systems for land cover monitoring. On the reverse is a table that compares a selection of these systems, whose data are globally available in a form suitable for land cover analysis. We hope the information presented will help you assess the utility of remotely sensed image to meet your needs.

Satellite clinics in academic ophthalmology programs: an exploratory study of successes and challenges.

PubMed

Kuo, Irene C

2013-12-14

Major academic ophthalmology departments have been expanding by opening multi-office locations ("satellites"). This paper offers a first glimpse into satellites of academic ophthalmology departments. Leaders of seven medium to large, geographically diverse departments agreed to participate. One- to two-hour phone interviews were conducted to assess the features of their satellite practices. Success as clinical entities, profitability, and access to patients were stated goals for most satellites. In approximate descending order, refractive surgery, retina, oculoplastics, and pediatric ophthalmology were the most common subspecialties offered. Faculty staffing ranged from recruitment specifically for satellites to rotation of existing faculty. Except for a department with only one academic track, satellite doctors were a mix of tenure and mostly non-tenure track faculty. According to these department leaders, scholarly productivity of satellite faculty was similar to that of colleagues at the main campus, though research was more community-based and clinical in nature. Fellowship but little resident education occurred at satellites. Though it was agreed that satellite practices were integral to department finances, they accounted for a smaller percentage of revenues than of total departmental visits. Satellite offices have offered access to a better payor mix and have boosted the finances of academic ophthalmology departments. Challenges include maintaining collegiality with referring community physicians, integrating faculty despite geographic distance, preserving the department's academic "brand name," and ensuring consistent standards and operating procedures. Satellite clinics will likely help departments meet some of the challenges of health care reform.

Introduction to the Personal Access Satellite System Study

NASA Technical Reports Server (NTRS)

Sue, Miles K.

1990-01-01

A recent study by the National Telecommunications and Information Administration (NTIA) has concluded that the 21st century will be the age of information in which the telecommunication infrastructure will be vital to the social and economic well being of society. To meet the challenge of the coming age, JPL has been performing studies on a personal access satellite system (PASS) for the 21st century. The PASS study can be traced back to a study in which the technical feasibility and potential applications of a high frequency, low data rate satellite system were identified using small fixed terminals. Herein, the PASS concept is described along with the strawman design. Then the key challenges are identified along with possible solutions. Finally, the plan for the future is summarized from the key results.

Weather Prediction Improvement Using Advanced Satellite Technology

NASA Technical Reports Server (NTRS)

Einaudi, Franco; Uccellini, L.; Purdom, J.; Rogers, D.; Gelaro, R.; Dodge, J.; Atlas, R.; Lord, S.

2001-01-01

We discuss in this paper some of the problems that exist today in the fall utilization of satellite data to improve weather forecasts and we propose specific recommendations to solve them. This discussion can be viewed as an aspect of the general debate on how best to organize the transition from research to operational satellites and how to evaluate the impact of a research instrument on numerical weather predictions. A method for providing this transition is offered by the National Polar-Orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project (NPP). This mission will bridge the time between the present NOAA and Department of Defense (DOD) polar orbiting missions and the initiation of the converged NPOESS series and will evaluate some of the Earth Observing System (EOS) instruments as appropriate for operational missions. Thus, this mission can be viewed as an effort to meet the operational requirements of NOAA and DOD and the research requirements of NASA. More generally, however, it can be said that the process of going from the conception of new, more advanced instruments to their operational implementation and full utilization by the weather forecast communities is not optimal. Instruments developed for research purposes may have insufficient funding to explore their potential operational capabilities. Furthermore, instrument development programs designed for operational satellites typically have insufficient funding for assimilation algorithms needed to transform the satellite observations into data that can be used by sophisticated global weather forecast models. As a result, years often go by before satellite data are efficiently used for operational forecasts. NASA and NOAA each have unique expertise in the design of satellite instruments, their use for basic and applied research and their utilization in weather and climate research. At a time of limited resources, the two agencies must combine their efforts to work toward common

Overview of intercalibration of satellite instruments

USGS Publications Warehouse

Chander, G.; Hewison, T.J.; Fox, N.; Wu, X.; Xiong, X.; Blackwell, W.J.

2013-01-01

Inter-calibration of satellite instruments is critical for detection and quantification of changes in the Earth’s environment, weather forecasting, understanding climate processes, and monitoring climate and land cover change. These applications use data from many satellites; for the data to be inter-operable, the instruments must be cross-calibrated. To meet the stringent needs of such applications requires that instruments provide reliable, accurate, and consistent measurements over time. Robust techniques are required to ensure that observations from different instruments can be normalized to a common scale that the community agrees on. The long-term reliability of this process needs to be sustained in accordance with established reference standards and best practices. Furthermore, establishing physical meaning to the information through robust Système International d'unités (SI) traceable Calibration and Validation (Cal/Val) is essential to fully understand the parameters under observation. The processes of calibration, correction, stability monitoring, and quality assurance need to be underpinned and evidenced by comparison with “peer instruments” and, ideally, highly calibrated in-orbit reference instruments. Inter-calibration between instruments is a central pillar of the Cal/Val strategies of many national and international satellite remote sensing organizations. Inter-calibration techniques as outlined in this paper not only provide a practical means of identifying and correcting relative biases in radiometric calibration between instruments but also enable potential data gaps between measurement records in a critical time series to be bridged. Use of a robust set of internationally agreed upon and coordinated inter-calibration techniques will lead to significant improvement in the consistency between satellite instruments and facilitate accurate monitoring of the Earth’s climate at uncertainty levels needed to detect and attribute the mechanisms

Joint Polar Satellite System (JPSS) Common Ground System (CGS) Current Technical Performance Measures

NASA Astrophysics Data System (ADS)

Cochran, S.; Panas, M.; Jamilkowski, M. L.; Miller, S. W.

2015-12-01

ABSTRACT The National Oceanic and Atmospheric Administration (NOAA) and National Aeronautics and Space Administration (NASA) are jointly acquiring the next-generation civilian weather and environmental satellite system: the Joint Polar Satellite System (JPSS). The Joint Polar Satellite System will replace the afternoon orbit component and ground processing system of the current Polar-orbiting Operational Environmental Satellites (POES) managed by NOAA. The JPSS satellites will carry a suite of sensors designed to collect meteorological, oceanographic, climatological and geophysical observations of the Earth. The ground processing system for JPSS is known as the JPSS Common Ground System (JPSS CGS). Developed and maintained by Raytheon Intelligence, Information and Services (IIS), the CGS is a multi-mission enterprise system serving NOAA, NASA and their national and international partners. The CGS has demonstrated its scalability and flexibility to incorporate multiple missions efficiently and with minimal cost, schedule and risk, while strengthening global partnerships in weather and environmental monitoring. The CGS architecture is being upgraded to Block 2.0 in 2015 to "operationalize" S-NPP, leverage lessons learned to date in multi-mission support, take advantage of more reliable and efficient technologies, and satisfy new requirements and constraints in the continually evolving budgetary environment. To ensure the CGS meets these needs, we have developed 49 Technical Performance Measures (TPMs) across 10 categories, such as data latency, operational availability and scalability. This paper will provide an overview of the CGS Block 2.0 architecture, with particular focus on the 10 TPM categories listed above. We will provide updates on how we ensure the deployed architecture meets these TPMs to satisfy our multi-mission objectives with the deployment of Block 2.0.

The Mailbox Computer System for the IAEA verification experiment on HEU downlending at the Portsmouth Gaseous Diffusion Plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aronson, A.L.; Gordon, D.M.

IN APRIL 1996, THE UNITED STATES (US) ADDED THE PORTSMOUTH GASEOUS DIFFUSION PLANT TO THE LIST OF FACILITIES ELIGIBLE FOR THE APPLICATION OF INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA) SAFEGUARDS. AT THAT TIME, THE US PROPOSED THAT THE IAEA CARRY OUT A ''VERIFICATION EXPERIMENT'' AT THE PLANT WITH RESPECT TO DOOWNBLENDING OF ABOUT 13 METRIC TONS OF HIGHLY ENRICHED URANIUM (HEU) IN THE FORM OF URANIUM HEXAFLUROIDE (UF6). DURING THE PERIOD DECEMBER 1997 THROUGH JULY 1998, THE IAEA CARRIED OUT THE REQUESTED VERIFICATION EXPERIMENT. THE VERIFICATION APPROACH USED FOR THIS EXPERIMENT INCLUDED, AMONG OTHER MEASURES, THE ENTRY OF PROCESS-OPERATIONAL DATA BYmore » THE FACILITY OPERATOR ON A NEAR-REAL-TIME BASIS INTO A ''MAILBOX'' COMPUTER LOCATED WITHIN A TAMPER-INDICATING ENCLOSURE SEALED BY THE IAEA.« less

CASTOR: Cathode/Anode Satellite Thruster for Orbital Repositioning

NASA Technical Reports Server (NTRS)

Mruphy, Gloria A.

2010-01-01

The purpose of CASTOR (Cathode/Anode Satellite Thruster for Orbital Repositioning) satellite is to demonstrate in Low Earth Orbit (LEO) a nanosatellite that uses a Divergent Cusped Field Thruster (DCFT) to perform orbital maneuvers representative of an orbital transfer vehicle. Powered by semi-deployable solar arrays generating 165W of power, CASTOR will achieve nearly 1 km/s of velocity increment over one year. As a technology demonstration mission, success of CASTOR in LEO will pave the way for a low cost, high delta-V orbital transfer capability for small military and civilian payloads in support of Air Force and NASA missions. The educational objective is to engage graduate and undergraduate students in critical roles in the design, development, test, carrier integration and on-orbit operations of CASTOR as a supplement to their curricular activities. This program is laying the foundation for a long-term satellite construction program at MIT. The satellite is being designed as a part of AFRL's University Nanosatellite Program, which provides the funding and a framework in which student satellite teams compete for a launch to orbit. To this end, the satellite must fit within an envelope of 50cmx50cmx60cm, have a mass of less than 50kg, and meet stringent structural and other requirements. In this framework, the CASTOR team successfully completed PDR in August 2009 and CDR in April 2010 and will compete at FCR (Flight Competition Review) in January 2011. The complexity of the project requires implementation of many systems engineering techniques which allow for development of CASTOR from conception through FCR and encompass the full design, fabrication, and testing process.

National aerospace meeting of the Institute of Navigation

NASA Astrophysics Data System (ADS)

Fell, Patrick

The program for this year's aerospace meeting of The Institute of Navigation addressed developments in the evolving Global Positioning System (GPS) of navigation satellites, inertial navigation systems, and other electronic navigation systems and their applications. Also included in the program were a limited number of papers addressing the geodetic use of the GPS system.The Global Positioning System is a constellation of 18 navigation satellites being developed by the Department of Defense to provide instantaneous worldwide navigation. The system will support a multitude of military applications. The first paper by Jacobson reviewed the engineering development of GPS navigation receivers stressing the use of common hardware and software modules. A later paper by Ould described the mechanization of a digital receiver for GPS applications designed for faster acquisition of the spread spectrum satellite transmissions than analog receivers. The paper by Brady discussed the worldwide coverage that is provided by the limited number of satellites that will constitute the GPS constellation through 1983. The capability provided by the satellites presently on orbit would support a variety of experiments at almost any location. Tables of multiple satellite availability are provided for numerous worldwide locations. For civil aviation applications, Vogel addressed the satellite geometry considerations for low cost GPS user equipment, Esposito described the Federal Aviation Administration acceptance tests of a GPS navigation receiver, and Hopkins discussed the design and capability of an integrated GPS strapdown attitude and heading reference system for avionics.

Spacecraft design project: High temperature superconducting infrared imaging satellite

NASA Technical Reports Server (NTRS)

1991-01-01

The High Temperature Superconductor Infrared Imaging Satellite (HTSCIRIS) is designed to perform the space based infrared imaging and surveillance mission. The design of the satellite follows the black box approach. The payload is a stand alone unit, with the spacecraft bus designed to meet the requirements of the payload as listed in the statement of work. Specifications influencing the design of the spacecraft bus were originated by the Naval Research Lab. A description of the following systems is included: spacecraft configuration, orbital dynamics, radio frequency communication subsystem, electrical power system, propulsion, attitude control system, thermal control, and structural design. The issues of testing and cost analysis are also addressed. This design project was part of the course Advanced Spacecraft Design taught at the Naval Postgraduate School.

Satellite Power Systems (SPS) concept definition study, exhibit C. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

Hanley, G. M.

1979-01-01

The Department of Energy (DOE) is currently conducting an evaluation of approaches to provide energy to meet demands in the post-2000 time period. The Satellite Power System (SPS) is a candidate for producing significant quantities of base-load power using solar energy as the source. The SPS concept is illustrated for a solar photovoltaic concept. A satellite, located at geosynchronous orbit, converts solar energy to dc electrical energy using large solar arrays. This study is a continuing effort to provide system definition data to aid in the evaluation of the SPS concept.

Broadcasting satellite feeder links - Characteristics and planning

NASA Technical Reports Server (NTRS)

Kiebler, J. W.

1982-01-01

The paper presents the results of recent studies by the Feeder Link Sub-Working Group of the FCC Advisory Committee for the 1983 Regional Administrative Radio Conference (RARC). These studies conclude that specification of a few key parameters will make feeder link planning relatively straightforward. Feeder links can be located anywhere within a country if satellite orbit locations are separated by 10 deg for adjacent service areas and key parameter values presented in the paper are adopted. Colocated satellites serving a common service area need special attention to attain sufficient isolation between a desired channel and its adjacent cross-polarized channels and alternate co-polarized channels. In addition to presenting planning conclusions by the Advisory Committee, the paper presents and analyzes actions of the International Radio Consultative Committee's Conference Planning Meeting (CPM) concerning feeder links. The CPM reached conclusions similar to, and compatible with, those of the Advisory Committee.

Advanced Communications Technology Satellite (ACTS). Phase 1: Industrial/academic experimenters

NASA Technical Reports Server (NTRS)

Maisel, James E.; Nowlin, Robert W.

1992-01-01

This report presents the work done at Arizona State University under the ACTS Experimenters Program. The main thrust of the Program was to develop experiments to test, evaluate, and prove the commercial worthiness of the ACTS satellite which is scheduled for launch in 1993. To accomplish this goal, meetings were held with various governmental, industrial, and academic units to discuss the ACTS satellite and its technology and possible experiments that would generate industrial interest and support for ASU's efforts. Several local industries generated several experiments of their own. The investigators submitted several experiments of educational, medical, commercial, and technical value and interest. The disposition of these experimental proposals is discussed in this report.

The Core Avionics System for the DLR Compact-Satellite Series

NASA Astrophysics Data System (ADS)

Montenegro, S.; Dittrich, L.

2008-08-01

The Standard Satellite Bus's core avionics system is a further step in the development line of the software and hardware architecture which was first used in the bispectral infrared detector mission (BIRD). The next step improves dependability, flexibility and simplicity of the whole core avionics system. Important aspects of this concept were already implemented, simulated and tested in other ESA and industrial projects. Therefore we can say the basic concept is proven. This paper deals with different aspects of core avionics development and proposes an extension to the existing core avionics system of BIRD to meet current and future requirements regarding flexibility, availability, reliability of small satellite and the continuous increasing demand of mass memory and computational power.

Principle characteristics of the National Earth Observation Satellite. Project SPOT

NASA Technical Reports Server (NTRS)

Cazenave, M.

1977-01-01

A recent meeting of the Economic and Social Committee examined the programs and means currently being implemented by France in the field in the field of space research and industry which could bring about fast results. This was prompted by man's desire to insure rational resource management of his planet and by man's awareness of the definite contribution that space observation can make to this field of research. Through discussion, the Economic and Social Committee has approved the plan for creating an earth observation satellite. A detailed discussion of the principle characteristics of this earth observation satellite include the objectives, the orbit, characteristics and operations of the platform, maintenance, attitude measurement, the power available and many other characteristics.

INF and IAEA: A comparative analysis of verification strategy. [Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scheinman, L.; Kratzer, M.

1992-07-01

This is the final report of a study on the relevance and possible lessons of Intermediate Range Nuclear Force (INF) verification to the International Atomic Energy Agency (IAEA) international safeguards activities.

The 1977 WARC on broadcasting satellites - Spectrum management aspects and implications

NASA Technical Reports Server (NTRS)

Gould, R. G.; Reinhart, E. E.

1977-01-01

Broadcasting satellites are allocated as a primary service in the band 11.7-12.2 GHz (11.7-12.5 GHz in Europe, Africa, and the USSR), but the band is also allocated on a primary basis (equal sharing) to other services - fixed, mobile, broadcasting, and fixed satellite. Presented with these difficult sharing situations, delegates from over 100 countries met at an ITU World Administrative Radio Conference in 1977 to develop a plan for broadcasting satellites. Many nations wanted a plan that would assign to them now, reserved orbital locations and channel asignments for their future use. Other countries wanted a plan adopted now for future broadcasting satellites which assigned specific channels to specific areas on the ground so that they could use the remaining frequencies to provide terrestrial service right away. This paper describes the 'Plan' developed at the conference and points out how the principles of spectrum management were employed. It also discusses the implications for future international management of the spectrum growing out of this meeting.

Integrated Satellite Control in REIMEI (INDEX) Satellite

NASA Astrophysics Data System (ADS)

Fukuda, Seisuke; Mizuno, Takahide; Sakai, Shin-Ichiro; Fukushima, Yousuke; Saito, Hirobumi

REIMEI/INDEX (INnovative-technology Demonstration EXperiment) is a 70kg class small satellite which the Institute of Space and Astronautical Science, Japan Exploration Agency, ISAS/JAXA, has developed for observation of auroral small-scale dynamics as well as demonstration of advanced satellite technologies. An important engineering mission of REIMEI is integrated satellite control using commercial RISC CPUs with a triple voting system in order to ensure fault-tolerance against radiation hazards. Software modules concerning every satellite function, such as attitude control, data handling, and mission applications, work cooperatively so that highly sophisticated satellite control can be performed. In this paper, after a concept of the integrated satellite control is introduced, the Integrated Controller Unit (ICU) is described in detail. Also unique topics in developing the integrated control system are shown.

GSFC network operations with Tracking and Data Relay Satellites

NASA Astrophysics Data System (ADS)

Spearing, R.; Perreten, D. E.

The Tracking and Data Relay Satellite System (TDRSS) Network (TN) has been developed to provide services to all NASA User spacecraft in near-earth orbits. Three inter-relating entities will provide these services. The TN has been transformed from a network continuously changing to meet User specific requirements to a network which is flexible to meet future needs without significant changes in operational concepts. Attention is given to the evolution of the TN network, the TN capabilities-space segment, forward link services, tracking services, return link services, the three basic capabilities, single access services, multiple access services, simulation services, the White Sands Ground Terminal, the NASA communications network, and the network control center.

GSFC network operations with Tracking and Data Relay Satellites

NASA Technical Reports Server (NTRS)

Spearing, R.; Perreten, D. E.

1984-01-01

The Tracking and Data Relay Satellite System (TDRSS) Network (TN) has been developed to provide services to all NASA User spacecraft in near-earth orbits. Three inter-relating entities will provide these services. The TN has been transformed from a network continuously changing to meet User specific requirements to a network which is flexible to meet future needs without significant changes in operational concepts. Attention is given to the evolution of the TN network, the TN capabilities-space segment, forward link services, tracking services, return link services, the three basic capabilities, single access services, multiple access services, simulation services, the White Sands Ground Terminal, the NASA communications network, and the network control center.

Testing the methodology for dosimetry audit of heterogeneity corrections and small MLC-shaped fields: Results of IAEA multi-center studies

PubMed Central

Izewska, Joanna; Wesolowska, Paulina; Azangwe, Godfrey; Followill, David S.; Thwaites, David I.; Arib, Mehenna; Stefanic, Amalia; Viegas, Claudio; Suming, Luo; Ekendahl, Daniela; Bulski, Wojciech; Georg, Dietmar

2016-01-01

Abstract The International Atomic Energy Agency (IAEA) has a long tradition of supporting development of methodologies for national networks providing quality audits in radiotherapy. A series of co-ordinated research projects (CRPs) has been conducted by the IAEA since 1995 assisting national external audit groups developing national audit programs. The CRP ‘Development of Quality Audits for Radiotherapy Dosimetry for Complex Treatment Techniques’ was conducted in 2009–2012 as an extension of previously developed audit programs. Material and methods. The CRP work described in this paper focused on developing and testing two steps of dosimetry audit: verification of heterogeneity corrections, and treatment planning system (TPS) modeling of small MLC fields, which are important for the initial stages of complex radiation treatments, such as IMRT. The project involved development of a new solid slab phantom with heterogeneities containing special measurement inserts for thermoluminescent dosimeters (TLD) and radiochromic films. The phantom and the audit methodology has been developed at the IAEA and tested in multi-center studies involving the CRP participants. Results. The results of multi-center testing of methodology for two steps of dosimetry audit show that the design of audit procedures is adequate and the methodology is feasible for meeting the audit objectives. A total of 97% TLD results in heterogeneity situations obtained in the study were within 3% and all results within 5% agreement with the TPS predicted doses. In contrast, only 64% small beam profiles were within 3 mm agreement between the TPS calculated and film measured doses. Film dosimetry results have highlighted some limitations in TPS modeling of small beam profiles in the direction of MLC leave movements. Discussion. Through multi-center testing, any challenges or difficulties in the proposed audit methodology were identified, and the methodology improved. Using the experience of these

Proceedings of the Twelfth NASA Propagation Experimenters Meeting (NAPEX 12)

NASA Technical Reports Server (NTRS)

Davarian, Faramaz (Editor)

1988-01-01

The NASA Propagation Experimenters Meeting was convened on June 9 and 10, 1988. Pilot Field Experiments propagation studies, mobile communication systems, signal fading, communication satellites rain gauge network measurements, atmospheric attenuation studies, optical communication through the atmosphere, and digital beacon receivers were among the topics discussed.

Satellite-tracking and earth-dynamics research programs. [NASA Programs on satellite orbits and satellite ground tracks of geodetic satellites

NASA Technical Reports Server (NTRS)

1974-01-01

Observations and research progress of the Smithsonian Astrophysical Observatory are reported. Satellite tracking networks (ground stations) are discussed and equipment (Baker-Nunn cameras) used to observe the satellites is described. The improvement of the accuracy of a laser ranging system of the ground stations is discussed. Also, research efforts in satellite geodesy (tides, gravity anomalies, plate tectonics) is discussed. The use of data processing for geophysical data is examined, and a data base for the Earth and Ocean Physics Applications Program is proposed. Analytical models of the earth's motion (computerized simulation) are described and the computation (numerical integration and algorithms) of satellite orbits affected by the earth's albedo, using computer techniques, is also considered. Research efforts in the study of the atmosphere are examined (the effect of drag on satellite motion), and models of the atmosphere based on satellite data are described.

The impact of the International Atomic Energy Agency (IAEA) program on radiation and tissue banking in Argentina.

PubMed

Kairiyama, Eulogia; Morales Pedraza, Jorge

2009-05-01

Tissue banking activities in Argentina started in 1993. The regulatory and controlling national authority on organ, tissue and cells for transplantation activity is the National Unique Coordinating Central Institute for Ablation and Implant (INCUCAI). Three tissue banks were established under the IAEA program and nine other banks participated actively in the implementation of this program. As result of the implementation of the IAEA program in Argentina and the work done by the established tissue banks, more and more hospitals are now using, in a routine manner, radiation sterilised tissues processed by these banks. During the period 1992-2005, more than 21 016 tissues were produced and irradiated in the tissue banks participating in the IAEA program. Within the framework of the training component of the IAEA program, Argentina has been selected to host the Regional Training Centre for Latin American. In this centre, tissue bank operators and medical personal from Latin American countries were trained. Since 1999, Argentina has organised four regular regional training courses and two virtual regional training courses. More than twenty (20) tissue bank operators and medical personnel from Argentina were trained under the IAEA program in the six courses organised in the country. In general, ninety (96) tissue bank operators and medical personnel from eight Latin-American countries were trained in the Buenos Aires regional training centre. From Argentina 16 students graduated in these courses.

Training in Tbilisi nuclear facility provides new sampling perspectives for IAEA inspectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brim, Cornelia P.

2016-06-08

Office of Nonproliferation and Arms Control- (NPAC-) sponsored training in a “cold” nuclear facility in Tbilisi, Georgia provides International Atomic Energy Agency (IAEA) inspectors with a new perspective on environmental sampling strategies. Sponsored by the Nuclear Safeguards program under the NPAC, Pacific Northwest National Laboratory (PNNL) experts have been conducting an annual weeklong class for IAEA inspectors in a closed nuclear facility since 2011. The Andronikashvili Institute of Physics and the Republic of Georgia collaborate with PNNL to provide the training, and the U.S. Department of State, the U.S. Embassy in Tbilisi and the U.S. Mission to International Organizations inmore » Vienna provide logistical support.« less

US objectives generally achieved at broadcasting satellite international conference. Improvements can help in future conferences

NASA Astrophysics Data System (ADS)

1984-08-01

The implementation of broadcasting satellite service for the Western Hemisphere was planned. Broadcasting satellites transmit television programs and other information services from Earth orbit to home or office antennas. At the request of the Senate Appropriations Subcommittee on Commerce, Justice, State and the Judiciary, GAO reviewed conference results as compared to established conference objectives and examined the interagency coordination of U.S. participation in this international conference. The United States basically achieved its two most important conference objectives: adopting a technically and procedurally flexible plan for broadcasting satellite service and obtaining a sufficient allocation of satellite orbit slots and frequencies to meet domestic needs. The U.S. was unable, however, to obtain agreement on adopting a maximum signal power level for satellites. The Department of State could improve its preparation, internal coordination, and administrative support for future international conferences and recommends actions to the Secretary of State to improve its international telecommunications activities.

Satellite clinics in academic ophthalmology programs: an exploratory study of successes and challenges

PubMed Central

2013-01-01

Background Major academic ophthalmology departments have been expanding by opening multi-office locations (“satellites”). This paper offers a first glimpse into satellites of academic ophthalmology departments. Methods Leaders of seven medium to large, geographically diverse departments agreed to participate. One- to two-hour phone interviews were conducted to assess the features of their satellite practices. Results Success as clinical entities, profitability, and access to patients were stated goals for most satellites. In approximate descending order, refractive surgery, retina, oculoplastics, and pediatric ophthalmology were the most common subspecialties offered. Faculty staffing ranged from recruitment specifically for satellites to rotation of existing faculty. Except for a department with only one academic track, satellite doctors were a mix of tenure and mostly non-tenure track faculty. According to these department leaders, scholarly productivity of satellite faculty was similar to that of colleagues at the main campus, though research was more community-based and clinical in nature. Fellowship but little resident education occurred at satellites. Though it was agreed that satellite practices were integral to department finances, they accounted for a smaller percentage of revenues than of total departmental visits. Conclusions Satellite offices have offered access to a better payor mix and have boosted the finances of academic ophthalmology departments. Challenges include maintaining collegiality with referring community physicians, integrating faculty despite geographic distance, preserving the department’s academic “brand name,” and ensuring consistent standards and operating procedures. Satellite clinics will likely help departments meet some of the challenges of health care reform. PMID:24330741

Satellite Emission Range Inferred Earth Survey (SERIES) project

NASA Technical Reports Server (NTRS)

Buennagel, L. A.; Macdoran, P. F.; Neilan, R. E.; Spitzmesser, D. J.; Young, L. E.

1984-01-01

The Global Positioning System (GPS) was developed by the Department of Defense primarily for navigation use by the United States Armed Forces. The system will consist of a constellation of 18 operational Navigation Satellite Timing and Ranging (NAVSTAR) satellites by the late 1980's. During the last four years, the Satellite Emission Range Inferred Earth Surveying (SERIES) team at the Jet Propulsion Laboratory (JPL) has developed a novel receiver which is the heart of the SERIES geodetic system designed to use signals broadcast from the GPS. This receiver does not require knowledge of the exact code sequence being transmitted. In addition, when two SERIES receivers are used differentially to determine a baseline, few cm accuracies can be obtained. The initial engineering test phase has been completed for the SERIES Project. Baseline lengths, ranging from 150 meters to 171 kilometers, have been measured with 0.3 cm to 7 cm accuracies. This technology, which is sponsored by the NASA Geodynamics Program, has been developed at JPL to meet the challenge for high precision, cost-effective geodesy, and to complement the mobile Very Long Baseline Interferometry (VLBI) system for Earth surveying.

Institute of Navigation Satellite Division, International Technical Meeting, 2nd, Colorado Springs, CO, Sept. 27-29, 1989, Proceedings

NASA Astrophysics Data System (ADS)

Various papers on navigation satellites are presented. The general topics considered include: overview and status of GPS, kinematic positioning, international developments and perspective on satellite positioning, test range applications, civil applications, and receiver developments and equipment. Consideration is given to multisensor integration, military applications, differential operation, integrity, propagation phenomena and measurement networks, and precise time and time transfer.

Magnetic dipole moment estimation and compensation for an accurate attitude control in nano-satellite missions

NASA Astrophysics Data System (ADS)

Inamori, Takaya; Sako, Nobutada; Nakasuka, Shinichi

2011-06-01

Nano-satellites provide space access to broader range of satellite developers and attract interests as an application of the space developments. These days several new nano-satellite missions are proposed with sophisticated objectives such as remote-sensing and observation of astronomical objects. In these advanced missions, some nano-satellites must meet strict attitude requirements for obtaining scientific data or images. For LEO nano-satellite, a magnetic attitude disturbance dominates over other environmental disturbances as a result of small moment of inertia, and this effect should be cancelled for a precise attitude control. This research focuses on how to cancel the magnetic disturbance in orbit. This paper presents a unique method to estimate and compensate the residual magnetic moment, which interacts with the geomagnetic field and causes the magnetic disturbance. An extended Kalman filter is used to estimate the magnetic disturbance. For more practical considerations of the magnetic disturbance compensation, this method has been examined in the PRISM (Pico-satellite for Remote-sensing and Innovative Space Missions). This method will be also used for a nano-astrometry satellite mission. This paper concludes that use of the magnetic disturbance estimation and compensation are useful for nano-satellites missions which require a high accurate attitude control.

Personal communications: An extension to the mobile satellite

NASA Technical Reports Server (NTRS)

Epstein, Murray; Draper, Francois

1990-01-01

As time progresses, customer demands become far more universal, involving integrated, simple to operate, cost effective services, with technology virtually transparent to the operator. Industry will be in a position of providing the necessary services to meet the subscribers' needs. Our resource based industries, transportation services, and utilities in the more rural and unserviced areas will require quality and affordable services that can only be supplied via satellite. One answer to these needs will be one- and two-way interoperable data messaging.

Trip report on IAEA Training Workshop on Implementation of Integrated Management Systems for Research Reactors (T3-TR-45496).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pratt, Richard J.

2013-11-01

From 17-21 June 2013, Sandia National Laboratories, Technical Area-V (SNL TA-V) represented the United States Department of Energy/National Nuclear Security Administration (DOE/NNSA) at the International Atomic Energy Agency (IAEA) Training Workshop (T3-TR-45486). This report gives a breakdown of the IAEA regulatory structure for those unfamiliar, and the lessons learned and observations that apply to SNL TA-V that were obtained from the workshop. The Safety Report Series, IAEA workshop final report, and SNL TA-V presentation are included as attachments.

Satellite Conferences

Science.gov Websites

NOAA- NESDIS Banner Satellite Conferences Collage images of earth, POES and GOES satellites in space HOME Call for Poster Abstracts DOC Logo NOAA Logo Satellite Conferences Welcome to the website for National Oceanic and Atmospheric Administration (NOAA) Satellite Conferences; past, present and future

First micro-satellite and new enhanced small satellite series in DFH Satellite Co. Ltd.

NASA Astrophysics Data System (ADS)

Zhang, Xiaomin; Xie, Bin; Dai, Shoulun; Zhang, Weiwen; Hu, Gefeng; Lan, Ding

2007-06-01

As one important department of CAST (Chinese Academy of Space Technology), with responsibility for small and micro-satellite development, DFH Satellite Co. Ltd. (DFHSat) manufactured and launched six small satellites from 2000 to 2004. Nowadays, DFHSat is developing micro-satellite and new enhanced small satellite series. The first micro-satellite as a basic type is named HummerSat-1. HummerSat-1 is three-axis stabilized with orbit control capability. Information and power control are implemented through an on-board network, GaAs solar cell and Li-ion battery are adopted to obtain and storage power, S-band TT&C and data transmission works are used. The payload of HummerSat-1 has a weight of 60 kg and power consumption of 200 W. The enhanced small satellite series based on technology of HummerSat-1 is planned by DFHSat. It would be aiming to form a continuative product spectrum of 80-200 kg. The enhanced series is focused on satisfying different missions, including earth remote sensing, communication, science exploration, etc.

Participation in proficiency test for tritium strontium and caesium isotopes in seawater 2015 (IAEA-RML-2015-02)

NASA Astrophysics Data System (ADS)

Visetpotjanakit, S.; Kaewpaluek, S.

2017-06-01

A proficiency test (PT) exercise has proposed by the International Atomic Energy Agency (IAEA) in the frame of the IAEA Technical Cooperation project RAS/7/021 “Marine benchmark study on the possible impact of the Fukushima radioactive releases in the Asia-Pacific Region for Caesium Determination in Sea Water” since 2012. In 2015 the exercise was referred to Proficiency Test for Tritium, Strontium and Caesium Isotopes in Seawater 2015 (IAEA-RML-2015-02) to analyse3H, 134Cs, 137Cs and90Sr in a seawater sample. OAP was one of the 17 laboratories from 15 countries from Asia-Pacific Region who joined the PT exercise. The aim of our participation was to validate our analytical performance for the accurate determination of radionuclides in seawater by developed methods of radiochemical analysis. OAP submitted results determining the concentration for the three elements i.e. 134Cs, 137Cs and90Sr in seawater to the IAEA. A critical review was made to check suitability of our methodology and the criteria for the accuracy, precision and trueness of our data. The results of both 134Cs and 137Cs passed all criteria which were assigned “Accepted” statuses. Whereas 90Sr analysis did not pass the accuracy test therefore it was considered as “Not accepted” Our results and all other participant results with critical comments were published in the IAEA proficiency test report.

Tethered Satellite System Contingency Investigation Board

NASA Technical Reports Server (NTRS)

1992-01-01

The Tethered Satellite System (TSS-1) was launched aboard the Space Shuttle Atlantis (STS-46) on July 31, 1992. During the attempted on-orbit operations, the Tethered Satellite System failed to deploy successfully beyond 256 meters. The satellite was retrieved successfully and was returned on August 6, 1992. The National Aeronautics and Space Administration (NASA) Associate Administrator for Space Flight formed the Tethered Satellite System (TSS-1) Contingency Investigation Board on August 12, 1992. The TSS-1 Contingency Investigation Board was asked to review the anomalies which occurred, to determine the probable cause, and to recommend corrective measures to prevent recurrence. The board was supported by the TSS Systems Working group as identified in MSFC-TSS-11-90, 'Tethered Satellite System (TSS) Contingency Plan'. The board identified five anomalies for investigation: initial failure to retract the U2 umbilical; initial failure to flyaway; unplanned tether deployment stop at 179 meters; unplanned tether deployment stop at 256 meters; and failure to move tether in either direction at 224 meters. Initial observations of the returned flight hardware revealed evidence of mechanical interference by a bolt with the level wind mechanism travel as well as a helical shaped wrap of tether which indicated that the tether had been unwound from the reel beyond the travel by the level wind mechanism. Examination of the detailed mission events from flight data and mission logs related to the initial failure to flyaway and the failure to move in either direction at 224 meters, together with known preflight concerns regarding slack tether, focused the assessment of these anomalies on the upper tether control mechanism. After the second meeting, the board requested the working group to complete and validate a detailed integrated mission sequence to focus the fault tree analysis on a stuck U2 umbilical, level wind mechanical interference, and slack tether in upper tether

Tethered Satellite System Contingency Investigation Board

NASA Astrophysics Data System (ADS)

1992-11-01

The Tethered Satellite System (TSS-1) was launched aboard the Space Shuttle Atlantis (STS-46) on July 31, 1992. During the attempted on-orbit operations, the Tethered Satellite System failed to deploy successfully beyond 256 meters. The satellite was retrieved successfully and was returned on August 6, 1992. The National Aeronautics and Space Administration (NASA) Associate Administrator for Space Flight formed the Tethered Satellite System (TSS-1) Contingency Investigation Board on August 12, 1992. The TSS-1 Contingency Investigation Board was asked to review the anomalies which occurred, to determine the probable cause, and to recommend corrective measures to prevent recurrence. The board was supported by the TSS Systems Working group as identified in MSFC-TSS-11-90, 'Tethered Satellite System (TSS) Contingency Plan'. The board identified five anomalies for investigation: initial failure to retract the U2 umbilical; initial failure to flyaway; unplanned tether deployment stop at 179 meters; unplanned tether deployment stop at 256 meters; and failure to move tether in either direction at 224 meters. Initial observations of the returned flight hardware revealed evidence of mechanical interference by a bolt with the level wind mechanism travel as well as a helical shaped wrap of tether which indicated that the tether had been unwound from the reel beyond the travel by the level wind mechanism. Examination of the detailed mission events from flight data and mission logs related to the initial failure to flyaway and the failure to move in either direction at 224 meters, together with known preflight concerns regarding slack tether, focused the assessment of these anomalies on the upper tether control mechanism. After the second meeting, the board requested the working group to complete and validate a detailed integrated mission sequence to focus the fault tree analysis on a stuck U2 umbilical, level wind mechanical interference, and slack tether in upper tether

Initiation of small-satellite formations via satellite ejector

NASA Astrophysics Data System (ADS)

McMullen, Matthew G

Small satellites can be constructed at a fraction of the cost of a full-size satellite. One full-size satellite can be replaced with a multitude of small satellites, offering expanded area coverage through formation flight. However, the shortcoming to the smaller size is usually a lack of thrusting capabilities. Furthermore, current designs for small satellite deployment mechanisms are only capable of love deployment velocities (on the order of meters per second). Motivated to address this shortcoming, a conceived satellite ejector would offer a significant orbit change by ejecting the satellite at higher deployment velocities (125-200 m/s). Focusing on the applications of the ejector, it is sought to bridge the gap in prior research by offering a method to initiate formation flight. As a precursor to the initiation, the desired orbit properties to initiate the formation are specified in terms of spacing and velocity change vector. From this, a systematic method is developed to find the relationship among velocity change vector, the desired orbit's orientation, and the spacing required to initiate the formation.

Advanced Solar Cells for Satellite Power Systems

NASA Technical Reports Server (NTRS)

Flood, Dennis J.; Weinberg, Irving

1994-01-01

The multiple natures of today's space missions with regard to operational lifetime, orbital environment, cost and size of spacecraft, to name just a few, present such a broad range of performance requirements to be met by the solar array that no single design can suffice to meet them all. The result is a demand for development of specialized solar cell types that help to optimize overall satellite performance within a specified cost range for any given space mission. Historically, space solar array performance has been optimized for a given mission by tailoring the features of silicon solar cells to account for the orbital environment and average operating conditions expected during the mission. It has become necessary to turn to entirely new photovoltaic materials and device designs to meet the requirements of future missions, both in the near and far term. This paper will outline some of the mission drivers and resulting performance requirements that must be met by advanced solar cells, and provide an overview of some of the advanced cell technologies under development to meet them. The discussion will include high efficiency, radiation hard single junction cells; monolithic and mechanically stacked multiple bandgap cells; and thin film cells.

Advanced solar cells for satellite power systems

NASA Astrophysics Data System (ADS)

Flood, Dennis J.; Weinberg, Irving

1994-11-01

The multiple natures of today's space missions with regard to operational lifetime, orbital environment, cost and size of spacecraft, to name just a few, present such a broad range of performance requirements to be met by the solar array that no single design can suffice to meet them all. The result is a demand for development of specialized solar cell types that help to optimize overall satellite performance within a specified cost range for any given space mission. Historically, space solar array performance has been optimized for a given mission by tailoring the features of silicon solar cells to account for the orbital environment and average operating conditions expected during the mission. It has become necessary to turn to entirely new photovoltaic materials and device designs to meet the requirements of future missions, both in the near and far term. This paper will outline some of the mission drivers and resulting performance requirements that must be met by advanced solar cells, and provide an overview of some of the advanced cell technologies under development to meet them. The discussion will include high efficiency, radiation hard single junction cells; monolithic and mechanically stacked multiple bandgap cells; and thin film cells.

Validating dose rate calibration of radiotherapy photon beams through IAEA/WHO postal audit dosimetry service.

PubMed

Jangda, Abdul Qadir; Hussein, Sherali

2012-05-01

In external beam radiation therapy (EBRT), the quality assurance (QA) of the radiation beam is crucial to the accurate delivery of the prescribed dose to the patient. One of the dosimetric parameters that require monitoring is the beam output, specified as the dose rate on the central axis under reference conditions. The aim of this project was to validate dose rate calibration of megavoltage photon beams using the International Atomic Energy Agency (IAEA)/World Health Organisation (WHO) postal audit dosimetry service. Three photon beams were audited: a 6 MV beam from the low-energy linac and 6 and 18 MV beams from a dual high-energy linac. The agreement between our stated doses and the IAEA results was within 1% for the two 6 MV beams and within 2% for the 18 MV beam. The IAEA/WHO postal audit dosimetry service provides an independent verification of dose rate calibration protocol by an international facility.

Satellite Power System (SPS) magnetron tube assessment study

NASA Technical Reports Server (NTRS)

Brown, W. C.

1981-01-01

The data base was extended with respect to the magnetron directional amplifier and its operating parameters that are pertinent to its application in the solar power satellite. On the basis of the resulting extended data base the design of a magnetron was outlined that would meet the requirements of the SPS application and a technology program was designed that would result in its development. The proposed magnetron design for the SPS is a close scale of the microwave oven magnetron, and resembles it closely physically and electrically.

Multi-Satellite Scheduling Approach for Dynamic Areal Tasks Triggered by Emergent Disasters

NASA Astrophysics Data System (ADS)

Niu, X. N.; Zhai, X. J.; Tang, H.; Wu, L. X.

2016-06-01

The process of satellite mission scheduling, which plays a significant role in rapid response to emergent disasters, e.g. earthquake, is used to allocate the observation resources and execution time to a series of imaging tasks by maximizing one or more objectives while satisfying certain given constraints. In practice, the information obtained of disaster situation changes dynamically, which accordingly leads to the dynamic imaging requirement of users. We propose a satellite scheduling model to address dynamic imaging tasks triggered by emergent disasters. The goal of proposed model is to meet the emergency response requirements so as to make an imaging plan to acquire rapid and effective information of affected area. In the model, the reward of the schedule is maximized. To solve the model, we firstly present a dynamic segmenting algorithm to partition area targets. Then the dynamic heuristic algorithm embedding in a greedy criterion is designed to obtain the optimal solution. To evaluate the model, we conduct experimental simulations in the scene of Wenchuan Earthquake. The results show that the simulated imaging plan can schedule satellites to observe a wider scope of target area. We conclude that our satellite scheduling model can optimize the usage of satellite resources so as to obtain images in disaster response in a more timely and efficient manner.

WE-AB-213-04: IAEA Support to Medical Physics in Africa and Latin America: Achievements and Challenges

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meghzifene, A.

to recruitment of professionals with incomplete education. In most LA countries only one MP responsible for each Center is currently mandated. Currently there is a large disparity among MP training programs and there is significant debate about the standards of MP graduate education in many LA countries. There are no commonly recognized academic programs, not enough clinical training sites and clinical training is not typically considered as part of the MP work. Economic pressures and high workloads also impede the creation of more training centers. The increasing need of qualified MPs require establishing a coordinated system of national Education & Training Centers (ETC), to meet the international standards of education and training in Medical Physics. This shortfall calls for support of organizations such as the IOMP, AAPM, ALFIM, IAEA, etc. Examples from various LA countries, as well as some proposed solutions, will be presented. In particular, we will discuss the resources that the AAPM and its members can offer to support regional programs. The ‘Medical Imaging’ physicist in the emerging world: Challenges and opportunities - Caridad Borrás (WGNIMP Chair) While the role of radiation therapy physicists in the emerging world is reasonably well established, the role of medical imaging physicists is not. The only perceived needs in radiology departments are equipment quality control and radiation protection, tasks that can be done by a technologist or a service engineer. To change the situation, the International Basic Safety Standard, which is adopted/adapted world-wide as national radiation protection regulations, states: “For diagnostic radiological procedures and image guided interventional procedures, the requirements of these Standards for medical imaging, calibration, dosimetry and quality assurance, including the acceptance and commissioning of medical radiological equipment, are fulfilled by or under the oversight of, or with the documented advice of

The SOLS TICE Project: Satellite Television and Audioconferencing in Continuing Professional Development for LIS Staff.

ERIC Educational Resources Information Center

Hughes, Alun; Priestley, John

1992-01-01

Describes SOLS TICE, the Satellite On-Line Searching Interactive Conferencing Experiment, conducted at the University of Plymouth (United Kingdom) to meet the training needs of staff in the library and information science (LIS) sector. Continuing professional development is discussed, instructional effectiveness and cost effectiveness are…

Non-Geo systems—where have all the satellites gone?

NASA Astrophysics Data System (ADS)

Ashford, Edward W.

2004-08-01

Non-GEO satellites were being hailed as the means that would bring connectivity to the masses. Anyone, it was said, would be able to buy a portable telephone that would allow them, no matter where they might be, to call or be called by anyone else in the world. In the early 1990s, there were predictions that, by now, literally many hundreds of new non-geostationary communications satellites would be in orbit. Furthermore, people all over the world would also be able to buy an inexpensive satellite terminal that would allow them to access the Internet with a broadband connection, at prices on par with or even far below what the terrestrial competition would be able to offer. Many companies were set up to compete to establish this "Nirvana of Communications." To do so, however, the companies in question would have to attract sufficient financial backing from investors to actually begin such an undertaking. Surprisingly, at least in retrospect, a tremendous amount of investment capital was forthcoming, and a number of contracts were awarded to manufacturers to develop the requisite satellite systems. Today, almost a decade later, satellite manufacturers and their suppliers have been subjected to a massive belt-tightening exercise as contracts were cancelled and expected future orders were not forthcoming. The launch vehicle industry, which had geared up to meet the bonanza of expected launch orders, is also going hungry. Where are all the proposed systems? This paper will attempt to answer this question, as well as to provide some insight into why the systems that are no longer with us fell by the wayside. Finally, it will look into the future and try to predict what the long-term prospects might be for non-GEO communication satellites in general.

Spectrum and orbit conservation as a factor in future mobile satellite system design

NASA Technical Reports Server (NTRS)

Bowen, Robert R.

1990-01-01

Access to the radio spectrum and geostationary orbit is essential to current and future mobile satellite systems. This access is difficult to obtain for current systems, and may be even more so for larger future systems. In this environment, satellite systems that minimize the amount of spectrum orbit resource required to meet a specific traffic requirement are essential. Several spectrum conservation techniques are discussed, some of which are complementary to designing the system at minimum cost. All may need to be implemented to the limits of technological feasibility if network growth is not to be constrained because of the lack of available spectrum-orbit resource.

Deterring Nuclear Proliferation: The Importance of IAEA Safeguards: A TEXTBOOK

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rosenthal, M.D.; Fishbone, L.G.; Gallini, L.

2012-03-13

Nuclear terrorism and nuclear proliferation are among the most pressing challenges to international peace and security that we face today. Iran and Syria remain in non-compliance with the safeguards requirements of the NPT, and the nuclear ambitions of North Korea remain unchecked. Despite these challenges, the NPT remains a cornerstone of the nuclear non-proliferation regime, and the safeguards implemented by the International Atomic Energy Agency (IAEA) under the NPT play a critical role in deterring nuclear proliferation.How do they work? Where did they come from? And what is their future? This book answers these questions. Anyone studying the field ofmore » nuclear non-proliferation will benefit from reading this book, and for anyone entering the field, the book will enable them to get a running start. Part I describes the foundations of the international safeguards system: its origins in the 1930s - when new discoveries in physics made it clear immediately that nuclear energy held both peril and promise - through the entry into force in 1970 of the NPT, which codified the role of IAEA safeguards as a means to verify states NPT commitments not to acquire nuclear weapons. Part II describes the NPT safeguards system, which is based on a model safeguards agreement developed specifically for the NPT, The Structure and Content of Agreements between the Agency and States required in connection with the Treaty on the Non-Proliferation of Nuclear Weapons, which has been published by the IAEA as INFCIRC/153. Part III describes events, especially in South Africa, the DPRK, and Iraq in the early 1990s, that triggered a transformation in the way in which safeguards were conceptualized and implemented.« less

Radionuclide transfer to fruit in the IAEA TRS No. 472

NASA Astrophysics Data System (ADS)

Carini, F.; Pellizzoni, M.; Giosuè, S.

2012-04-01

This paper describes the approach taken to present the information on fruits in the IAEA report TRS No. 472, supported by the IAEA-TECDOC-1616, which describes the key transfer processes, concepts and conceptual models regarded as important for dose assessment, as well as relevant parameters for modelling radionuclide transfer in fruits. Information relate to fruit plants grown in agricultural ecosystems of temperate regions. The relative significance of each pathway after release of radionuclides depends upon the radionuclide, the kind of crop, the stage of plant development and the season at time of deposition. Fruit intended as a component of the human diet is borne by plants that are heterogeneous in habits, and morphological and physiological traits. Information on radionuclides in fruit systems has therefore been rationalised by characterising plants in three groups: woody trees, shrubs, and herbaceous plants. Parameter values have been collected from open literature, conference proceedings, institutional reports, books and international databases. Data on root uptake are reported as transfer factor values related to fresh weight, being consumption data for fruits usually given in fresh weight.

Inter-satellite links for satellite autonomous integrity monitoring

NASA Astrophysics Data System (ADS)

Rodríguez-Pérez, Irma; García-Serrano, Cristina; Catalán Catalán, Carlos; García, Alvaro Mozo; Tavella, Patrizia; Galleani, Lorenzo; Amarillo, Francisco

2011-01-01

A new integrity monitoring mechanisms to be implemented on-board on a GNSS taking advantage of inter-satellite links has been introduced. This is based on accurate range and Doppler measurements not affected neither by atmospheric delays nor ground local degradation (multipath and interference). By a linear combination of the Inter-Satellite Links Observables, appropriate observables for both satellite orbits and clock monitoring are obtained and by the proposed algorithms it is possible to reduce the time-to-alarm and the probability of undetected satellite anomalies.Several test cases have been run to assess the performances of the new orbit and clock monitoring algorithms in front of a complete scenario (satellite-to-satellite and satellite-to-ground links) and in a satellite-only scenario. The results of this experimentation campaign demonstrate that the Orbit Monitoring Algorithm is able to detect orbital feared events when the position error at the worst user location is still under acceptable limits. For instance, an unplanned manoeuvre in the along-track direction is detected (with a probability of false alarm equals to 5 × 10-9) when the position error at the worst user location is 18 cm. The experimentation also reveals that the clock monitoring algorithm is able to detect phase jumps, frequency jumps and instability degradation on the clocks but the latency of detection as well as the detection performances strongly depends on the noise added by the clock measurement system.

Nutation and precession control of the High Energy Solar Physics (HESP) satellite

NASA Technical Reports Server (NTRS)

Jayaraman, C. P.; Robertson, B. P.

1993-01-01

The High Energy Solar Physics (HESP) spacecraft is an intermediate class satellite proposed by NASA to study solar high-energy phenomena during the next cycle of high solar activity in the 1998 to 2005 time frame. The HESP spacecraft is a spinning satellite which points to the sun with stringent pointing requirements. The natural dynamics of a spinning satellite includes an undesirable effect: nutation, which is due to the presence of disturbances and offsets of the spin axis from the angular momentum vector. The proposed Attitude Control System (ACS) attenuates nutation with reaction wheels. Precessing the spacecraft to track the sun in the north-south and east-west directions is accomplished with the use of torques from magnetic torquer bars. In this paper, the basic dynamics of a spinning spacecraft are derived, control algorithms to meet HESP science requirements are discussed and simulation results to demonstrate feasibility of the ACS concept are presented.

Nineteenth International Microgravity Measurements Group Meeting

NASA Technical Reports Server (NTRS)

DeLombard, Richard (Compiler)

2000-01-01

The Microgravity Measurements Group meetings provide a forum for an exchange of information and ideas about various aspects of microgravity acceleration research in international microgravity research programs. These meetings are sponsored by the PI Microgravity Services (PIMS) project at the NASA Glenn Research Center. The 19th MGMG meeting was held 11-13 July 2000 at the Sheraton Airport Hotel in Cleveland, Ohio. The 44 attendees represented NASA, other space agencies, universities, and commercial companies; 8 of the attendees were international representatives from Japan, Italy, Canada, Russia, and Germany. Twenty-seven presentations were made on a variety of microgravity environment topics including the International Space Station (ISS), acceleration measurement and analysis results, science effects from microgravity accelerations, vibration isolation, free flyer satellites, ground testing, vehicle characterization, and microgravity outreach and education. The meeting participants also toured three microgravity-related facilities at the NASA Glenn Research Center. Contained within the minutes is the conference agenda, which indicates each speaker, the title of their presentation, and the actual time of their presentation. The minutes also include the charts for each presentation, which indicate the authors' name(s) and affiliation. In some cases, a separate written report was submitted and has been Included here

Study of mobile satellite network based on GEO/LEO satellite constellation

NASA Astrophysics Data System (ADS)

Hu, Xiulin; Zeng, Yujiang; Wang, Ying; Wang, Xianhui

2005-11-01

Mobile satellite network with Inter Satellite Links (ISLs), which consists of non-geostationary satellites, has the characteristic of network topology's variability. This is a great challenge to the design and management of mobile satellite network. This paper analyzes the characteristics of mobile satellite network, takes multimedia Quality of Service (QoS) as the chief object and presents a reference model based on Geostationary Earth Orbit (GEO)/ Low Earth Orbit (LEO) satellite constellation which adapts to the design and management of mobile satellite network. In the reference model, LEO satellites constitute service subnet with responsibility for the access, transmission and switch of the multimedia services for mobile users, while GEO satellites constitute management subnet taking on the centralized management to service subnet. Additionally ground control centre realizes the whole monitoring and control via management subnet. Comparing with terrestrial network, the above reference model physically separates management subnet from service subnet, which not only enhances the advantage of centralized management but also overcomes the shortcoming of low reliability in terrestrial network. Routing of mobile satellite network based on GEO/LEO satellite constellation is also discussed in this paper.

NOTE: Monte Carlo simulation of correction factors for IAEA TLD holders

NASA Astrophysics Data System (ADS)

Hultqvist, Martha; Fernández-Varea, José M.; Izewska, Joanna

2010-03-01

The IAEA standard thermoluminescent dosimeter (TLD) holder has been developed for the IAEA/WHO TLD postal dose program for audits of high-energy photon beams, and it is also employed by the ESTRO-QUALity assurance network (EQUAL) and several national TLD audit networks. Factors correcting for the influence of the holder on the TL signal under reference conditions have been calculated in the present work from Monte Carlo simulations with the PENELOPE code for 60Co γ-rays and 4, 6, 10, 15, 18 and 25 MV photon beams. The simulation results are around 0.2% smaller than measured factors reported in the literature, but well within the combined standard uncertainties. The present study supports the use of the experimentally obtained holder correction factors in the determination of the absorbed dose to water from the TL readings; the factors calculated by means of Monte Carlo simulations may be adopted for the cases where there are no measured data.

Structural Bus and Release Mechanisms on the ST5 Satellites: Summary and Status

NASA Technical Reports Server (NTRS)

Rossoni, Peter

2007-01-01

The Space Technology 5 Mechanical System met the challenge of packaging a fully functional science and technology satellite system with its Deployer mechanism into a compact 0.07cu m volume. Three 25 kg satellites were orbited in constellation in March, 2006. The ST5 mechanical system is composed of 1) The Structural Bus; 2) Magnetometer Instrument Boom 3) Spacecraft Deployer Release Mechanism This system includes a highly integrated electronics enclosure as a multifunctional structure; a lightweight, magnetically clean Magnetometer Boom; the first use of Nitinol Shape-Memory Alloy trigger devices for deploying multiple spacecraft; an innovative compliant mount for the umbilical connector and a Deployer mechanism that imparts both separation velocity and mission spin rate to three constellation flying satellites These elements employed cutting-edge design and analysis tools, state-of-the-art testing facilities and proven engineering techniques to meet stringent performance criteria, enabling the mission s success.

Automatic Mosaicking of Satellite Imagery Considering the Clouds

NASA Astrophysics Data System (ADS)

Kang, Yifei; Pan, Li; Chen, Qi; Zhang, Tong; Zhang, Shasha; Liu, Zhang

2016-06-01

With the rapid development of high resolution remote sensing for earth observation technology, satellite imagery is widely used in the fields of resource investigation, environment protection, and agricultural research. Image mosaicking is an important part of satellite imagery production. However, the existence of clouds leads to lots of disadvantages for automatic image mosaicking, mainly in two aspects: 1) Image blurring may be caused during the process of image dodging, 2) Cloudy areas may be passed through by automatically generated seamlines. To address these problems, an automatic mosaicking method is proposed for cloudy satellite imagery in this paper. Firstly, modified Otsu thresholding and morphological processing are employed to extract cloudy areas and obtain the percentage of cloud cover. Then, cloud detection results are used to optimize the process of dodging and mosaicking. Thus, the mosaic image can be combined with more clear-sky areas instead of cloudy areas. Besides, clear-sky areas will be clear and distortionless. The Chinese GF-1 wide-field-of-view orthoimages are employed as experimental data. The performance of the proposed approach is evaluated in four aspects: the effect of cloud detection, the sharpness of clear-sky areas, the rationality of seamlines and efficiency. The evaluation results demonstrated that the mosaic image obtained by our method has fewer clouds, better internal color consistency and better visual clarity compared with that obtained by traditional method. The time consumed by the proposed method for 17 scenes of GF-1 orthoimages is within 4 hours on a desktop computer. The efficiency can meet the general production requirements for massive satellite imagery.

NOAA Interest in Small Satellite Solutions for Mitigation of Data Gaps

NASA Astrophysics Data System (ADS)

Caulfield, M.; Tewey, K.; John, P.

2016-12-01

The National Oceanic and Atmospheric Administration (NOAA) is undertaking a strategy to achieve satellite constellation robustness by 2023 to maintain continuity of polar satellite observations, which are central to NOAA's weather forecast capability. NOAA's plans include mitigation activities in the event of a loss of polar observations. In 2017, NOAA will begin development of the Earth Observing Nanosatellite - Microwave (EON-MW). EON-MW is a miniature microwave sounder that approximates the atmospheric profiling capabilities of the Advanced Technology Microwave Sounder (ATMS) instrument on the NOAA Joint Polar Satellite System (JPSS). NOAA is collaborating with the Massachusetts Institute of Technology's Lincoln Laboratory (MIT / LL) on EON-MW, which includes 2 years of risk reduction efforts to further define the EON-MW mission and identify and manage key technical risks. These studies will refine designs and evaluate system trades for operational earth observations from a U-class satellite platform, as well as examine microwave sensor concepts and investigated payload architecture to support microwave frequencies for atmospheric remote sensing. Similar to EON-MW, NOAA is also investigating the potential to mitigate against the loss of the JPSS Cross Track Infrared Sounder (CrIS) data with a CubeSat based mid-wave Infrared sounder. NOAA is collaborating with the Jet Propulsion Laboratory (JPL) to design the Earth Observation Nanosatellite-Infrared (EON-IR). EON-IR will leverage the NASA-JPL CubSat based infrared sounder CubSat Infrared Atmospheric Sounder (CIRAS) mission. In FY 2015 NOAA funded a study to analyze the feasibility of meeting the essential requirements of the CrIS from a CubeSat platform and began exploring the basic design of the EON-IR payload and bus. NOAA will continue to study EON-IR in 2016 by examining ways to modify the CIRAS design to better meet NOAA's observational and operational needs. These modifications will aim to increase mission

Earth Observatory Satellite system definition study. Report no. 4: Management approach recommendations

NASA Technical Reports Server (NTRS)

1974-01-01

A management approach for the Earth Observatory Satellite (EOS) which will meet the challenge of a constrained cost environment is presented. Areas of consideration are contracting techniques, test philosophy, reliability and quality assurance requirements, commonality options, and documentation and control requirements. The various functional areas which were examined for cost reduction possibilities are identified. The recommended management approach is developed to show the primary and alternative methods.

Effective Utilization of Satellite Observations for Assessing Transnational Impact of Disasters

NASA Astrophysics Data System (ADS)

Alozie, J. E.; Anuforom, A. C.

2014-12-01

General meteorological observations sources for the surface, upper air and outer space are conducted using different technological equipment and instruments that meet international standards prescribed and approved by the United Nations organizations such as the International Civil Aviation Organization (ICAO) and the World Meteorological Organization (WMO). Satellite weather observations are critical for effective monitoring of the developments, propagations and disseminations of cold clouds and their expected adverse weather conditions as they move across national and transnational boundaries. The Nigerian Meteorological Agency (NiMet) which is the national weather service provider for Nigeria, utilizes an array of satellite products obtained from mainly the European Meteorological Satellite (EUMETSAT) for its routine weather and climate monitoring and forecasts. Overtime, NiMet has used weather workstations such as MSG, SYNERGIE and now PUMA for accessing satellite products such as RGB, Infra-red, Water vapour and the Multi-sensor Precipitation Estimate (MPE) obtained at near real-time periods. The satellite imageries find extensive applications in the delivery of early warning of raising of severe weather conditions such as dust storm and dust haze during the harmattan season (November - February); and thunderstorm accompanied by severe lightning and destructive strong winds. The paper will showcase some special cases of the tracking of squall lines and issuance of weather alerts through the media. The good result is that there was limited damage to infrastructure and no loss of life from the flash floods caused by the heavy rainfall from the squally thunderstorm.

Scientific Satellites

DTIC Science & Technology

1967-01-01

414 S E S PC 210 SCIENTIFIC SATELLITES W.~YI to W.l WI* W FIGuRE 7-5.- Effects of vacuum on space components and types of vacuum pumps used in...origin, 16-17 Vacuum, effects on satellites, 207- relation to satellite dynamics, 90 210 , 284, 365 satellite research, 4, 18, 411, 584 simulation, 209...18 decades (_3 km to _..3 10-s A). (See fig. 1-1.) The charged- particle shielding effectiveness of the Earth’s magnetic field is also reduced at

The 22nd Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

NASA Technical Reports Server (NTRS)

Sydnor, Richard L. (Editor)

1990-01-01

Papers presented at the 22nd Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting are compiled. The following subject areas are covered: Rb, Cs, and H-based frequency standards and cryogenic and trapped-ion technology; satellite laser tracking networks, GLONASS timing, intercomparison of national time scales and international telecommunications; telecommunications, power distribution, platform positioning, and geophysical survey industries; military communications and navigation systems; and dissemination of precise time and frequency by means of GPS, GLONASS, MILSTAR, LORAN, and synchronous communication satellites.

Saturn's satellites: Potential for organic chemistry

NASA Astrophysics Data System (ADS)

Delitsky, M. L.; Lane, A. L.; Henry-Riyad, H.; Tidwell, T. T.

2003-05-01

The surfaces of the Saturnian satellites are subjected to irradiation from solar wind ions, photons, and magnetospheric ions and electrons. This bombardment will transform the chemical nature of the surfaces. At present, only water ice has been detected on their surfaces. Further studies by the Cassini spacecraft may reveal other molecules. If CO2 ice is found there, a whole panoply of new species may be detected. As nitrogen ions in the magnetosphere are thought to be an important species bombarding the satellites, Delitsky and Lane (2002) outlined the nitrogen oxides chemistry that may result from implantation of N+ into the water ice surfaces. Sittler et al (2002) showed that N+ ions originating from Titan will be enriched in the magnetospheric ion population as they move inwards towards Saturn, making the nitrogen oxides chemistry more likely. If CO2 is present, a complicated C-H-N-O chemistry may result from deposition of the N+ into a H2O/CO2 mixed ice, including nitriles, isocyanates, polymers, and amino acids. The combination of H2O/CO2 upon irradiation may also yield a complex mixture of hydrocarbons, esters, alcohols, organic acids and ketones. Possible chemical pathways and computations of their energetics will be presented. -Ref:- 1. Delitsky and Lane, Saturn's inner satellites: Ice chemistry and magnetosphere effects, JGR (Planets), Nov 2002, 3-1;; 2. Sittler et al., Energetic nitrogen ions within the inner magnetosphere of Saturn, Fall AGU meeting, Dec 2002, abstracts, pg F858, P21B-0379

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ricard-McCutchan, E.; Dimitriou, P.; Nichols, A. L.

The 21st meeting of the International Network of Nuclear Structure and Decay Data Evaluators was convened at the IAEA Headquarters, Vienna, from 20 to 24 April 2015 under the auspices of the IAEA Nuclear Data Section. This meeting was attended by 36 scientists from 15 Member States, plus IAEA staff, concerned with the compilation, evaluation and dissemination of nuclear structure and decay data. A summary of the meeting, data centre reports, various proposals considered, and actions agreed by the participants, as well as recommendations/conclusions are presented within this document.

The giant planets and their satellites: Report on the Cospar Symposium, Ottawa, Canada, May 18-21, 1982

USGS Publications Warehouse

Kivelson, M.G.; Behannon, K.W.; Cravens, T.E.; de Pater, I.; Johnson, T.V.; Matson, D.L.; Masursky, H.; Southwood, D.J.; Vasyliunas, V.M.

1983-01-01

A Symposium on the Giant Planets and Their Satellites was presented in conjunction with the Twenty-fourth Plenary Meeting of the Committee on Space Research. This paper summarizes the talks presented and places the remaining papers of this volume in context. ?? 1983.

DOD Use of Commercial Wideband Satellite Communications Systems: How Much is Needed, and How Do We Get It?

NASA Astrophysics Data System (ADS)

Hutchens, Robert E., III

2001-04-01

Joint force commanders must have the right information at the right time in order to make the best decisions to conduct successful contingency operations in defense of U.S. national security interests. A key enabler to this end is sufficient wideband satellite communications connectivity DoD's (Department of Defense) organic wideband satellite communications capabilities are inadequate, so commercial services must be used to overcome the shortfall. The problem is to dedicate enough resources in the most efficient manner to meet this growing need, and time is of the essence, This paper capitalizes on the vast work already accomplished concerning what DoD needs to do to obtain the commercial wideband satellite communications it needs. DoD is procuring advanced satellite ground terminals capable of using commercial wideband satellites and is contracting to launch more of its own capabilities, but the gap is continuing to widen. This paper offers a solution of procuring 140 percent of DoD's projected wideband satellite communications from commercial sources, to ensure sufficient capacity is available to support contingency operations.

U.S. experience in satellite servicing and linkage to the Space Station era

NASA Technical Reports Server (NTRS)

Browning, R. K.

1986-01-01

A history of on-orbit servicing and repair is given with emphasis placed on the Solar Maximum Repair Mission. The experience gained thus far in on-orbit servicing and the design of the Space Station's servicing capabilities impose the following requirements on users: (1) satellites must have a standard grapple for capture and a standard berthing interface, (2) Space Station safety requirements must meet to preclude damage to the Space Station or injury to the EVA crew, (3) sensitive instruments will need to implement remotely controlled protective devices to prevent damage, and (4) satellite thermal systems must be designed to maintain survival temperatures during transfer from orbit to the Space Station servicing facility.

Boomerang Satellites

NASA Astrophysics Data System (ADS)

Hesselbrock, Andrew; Minton, David A.

2017-10-01

We recently reported that the orbital architecture of the Martian environment allows for material in orbit around the planet to ``cycle'' between orbiting the planet as a ring, or as coherent satellites. Here we generalize our previous analysis to examine several factors that determine whether satellites accreting at the edge of planetary rings will cycle. In order for the orbiting material to cycle, tidal evolution must decrease the semi-major axis of any accreting satellites. In some systems, the density of the ring/satellite material, the surface mass density of the ring, the tidal parameters of the system, and the rotation rate of the primary body contribute to a competition between resonant ring torques and tidal dissipation that prevent this from occurring, either permanently or temporarily. Analyzing these criteria, we examine various bodies in our solar system (such as Saturn, Uranus, and Eris) to identify systems where cycling may occur. We find that a ring-satellite cycle may give rise to the current Uranian ring-satellite system, and suggest that Miranda may have formed from an early, more massive Uranian ring.

Solar Power Satellites: Reconsideration as Renewable Energy Source Based on Novel Approaches

NASA Astrophysics Data System (ADS)

Ellery, Alex

2017-04-01

Solar power satellites (SPS) are a solar energy generation mechanism that captures solar energy in space and converts this energy into microwave for transmission to Earth-based rectenna arrays. They offer a constant, high integrated energy density of 200 W/m2 compared to <10 W/m2 for other renewable energy sources. Despite this promise as a clean energy source, SPS have been relegated out of consideration due to their enormous cost and technological challenge. It has been suggested that for solar power satellites to become economically feasible, launch costs must decrease from their current 20,000/kg to <200/kg. Even with the advent of single-stage-to-orbit launchers which propose launch costs dropping to 2,000/kg, this will not be realized. Yet, the advantages of solar power satellites are many including the provision of stable baseload power. Here, I present a novel approach to reduce the specific cost of solar power satellites to 1/kg by leveraging two enabling technologies - in-situ resource utilization of lunar material and 3D printing of this material. Specifically, we demonstrate that electric motors may be constructed from lunar material through 3D printing representing a major step towards the development of self-replicating machines. Such machines have the capacity to build solar power satellites on the Moon, thereby bypassing the launch cost problem. The productive capacity of self-replicating machines favours the adoption of large constellations of small solar power satellites. This opens up additional clean energy options for combating climate change by meeting the demands for future global energy.

United States direct broadcast satellite system development

NASA Astrophysics Data System (ADS)

Dement, D. K.

1984-03-01

As the technology appears increasingly likely to meet the needs and as DBS regulatory activity becomes fixed, investment decisions will be made. With only modest technical risk for even the high-powered satellites, with little doubt that mass-produced earth terminals' gain-over-temperature of 10 dB or more can be attained for an acceptable price, and with the advent of acceptably priced individual descramblers for pay television, interest in DBS continues to grow. Present concerns center on market acceptance, competition, and programming availability. The variety of operational approaches revealed in FCC permit applications is seen as showing a willingness to risk, innovate, and move forward as quickly as possible.

NOAA WEATHER SATELLITES

Science.gov Websites

extent of snow cover. In addition, satellite sensors detect ice fields and map the movement of sea and greater danger near shore or any shallow waters? NATIONAL WEATHER SERVICE SATELLITE PRODUCTS NOAA's operational weather satellite system is composed of two types of satellites: geostationary operational

Satellite Docking Simulator with Generic Contact Dynamics Capabilities

NASA Astrophysics Data System (ADS)

Ma, O.; Crabtree, D.; Carr, R.; Gonthier, Y.; Martin, E.; Piedboeuf, J.-C.

2002-01-01

satellite servicing. Simulations are also instrumental in concept studies during proposals and early development stages. Finally, simulations are useful during the operational phase of satellite servicing: improving the operational procedures; training ground operators; command and control, etc. Hence the need exists for a Satellite Servicing Simulator, which will support a project throughout its lifecycle. The paper addresses a project to develop a Simulink-based Satellite Docking Simulator (SDS) with generic Contact Dynamics (CD) capabilities. The simulator is intended to meet immediate practical demands for development of complex docking systems and operations at MD Robotics. The docking phase is the most critical and complex phase of the entire servicing sequence, and without docking there is no servicing. Docking mechanisms are often quite complex, especially when built to dock with a satellite manufactured without special docking interfaces. For successful docking operations, the design of a docking system must take into consideration: complexity of 3D geometric shapes defining the contact interfaces; sophistication of the docking mechanism; friction and stiction at the contacting surfaces; compliance (stiffness) and damping, in all axes; positional (translation and rotation) misalignments and relative velocities, in all axes; inertial properties of the docking satellites (including their distribution); complexity of the drive mechanisms and control sub-systems for the overall docking system; fully autonomous or tele-operated docking from the ground; etc. The docking simulator, which makes use of the proven Contact Dynamics Toolkit (CDT) developed by MD Robotics, is thus practically indispensable for the docking system designer. The use of the simulator could greatly reduce the prototyping and development time of a docking interface. A special feature of the simulator, which required an update of CDT, is variable step-size integration. This new capability permits

Using Satellite Galaxies to Weigh the Milky Way

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2018-06-01

Weighing galaxies is a tricky business especially when that galaxy is our own! In a recent study, scientists have tackled this problem by harnessing incredibly precise measurements of the motions of Milky-Way satellites.A Challenging MeasurementLocations of some of the 50 satellite galaxies known around the Milky Way. [AndrewRT]Our spot in the middle of our galaxys disk makes it difficult for us to assess the total mass of gas, dust, stars, and dark matter surrounding us; estimates for the Milky Ways mass span from 700 billion to 2 trillion solar masses! Pinning down this number is critical for better understanding the structure and dynamics of our local universe.So whats the key to precisely weighing the Milky Way? A new study led by Ekta Patel (University of Arizona) presented at the American Astronomical Society meeting two weeks ago suggests it may be the barely preceptible motions of the small satellite galaxies that orbit around the Milky Way. Around 50 Milky-Way satellites are currently known, and simulations suggest that there may be up to 100200 in total. By watching the motions of these satellites, we can trace the potential of their host the Milky Way and estimate its mass.The Illustris-Dark simulation evolves our universe to the present day, providing a view of how dark matter organizes itself into galaxy halos over time. [Illustris Collaboration]Tiny Motions of Tiny GalaxiesIn this era of precision astronomy, remarkable measurements are becoming possible. In their study, Patel and collaborators use years of proper-motion observations from the Hubble Space Telescope for nine satellite galaxies of the Milky Way. The precision needed for measurements like these is insane: watching these satellites move is roughly like watching a human hair grow at the distance of the Moon.Rather than using the instantaneous position and velocity measured for a satellite which changes over time during the satellites orbit Patel and collaborators demonstrate that the

Onboard autonomous mission re-planning for multi-satellite system

NASA Astrophysics Data System (ADS)

Zheng, Zixuan; Guo, Jian; Gill, Eberhard

2018-04-01

This paper presents an onboard autonomous mission re-planning system for Multi-Satellites System (MSS) to perform onboard re-planing in disruptive situations. The proposed re-planning system can deal with different potential emergency situations. This paper uses Multi-Objective Hybrid Dynamic Mutation Genetic Algorithm (MO-HDM GA) combined with re-planning techniques as the core algorithm. The Cyclically Re-planning Method (CRM) and the Near Real-time Re-planning Method (NRRM) are developed to meet different mission requirements. Simulations results show that both methods can provide feasible re-planning sequences under unforeseen situations. The comparisons illustrate that using the CRM is average 20% faster than the NRRM on computation time. However, by using the NRRM more raw data can be observed and transmitted than using the CRM within the same period. The usability of this onboard re-planning system is not limited to multi-satellite system. Other mission planning and re-planning problems related to autonomous multiple vehicles with similar demands are also applicable.

The SCARLET{trademark} array for high power GEO satellites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spence, B.R.; Jones, P.A.; Eskenazi, M.I.

1997-12-31

The GEO satellite market is demanding increasingly capable spacecraft which, in turn, drives commercial spacecraft manufacturers to require significantly higher power solar arrays. As satellite capability increases the demand for high power array systems which are both cost and performance competitive becomes more crucial. Conventional rigid panel planar arrays, although suitable in the past, negatively impact spacecraft competitiveness for these new applications. The Solar Concentrator Array with Refractive Linear Element Technology (SCARLET{trademark}) represents an economically attractive solution for meeting these new high power requirements. When compared to conventional planar arrays, SCARLET provides substantially lower cost and higher deployed stiffness, competitivemore » mass, better producibility, and affordable use of high efficiency multijunction cells. This paper compares cost/performance characteristics of the SCARLET array to conventional planar arrays for high power GEO spacecraft applications. High power SCARLET array configurations are described, and inherent spacecraft and array level cost/performance benefits are presented.« less

Satellite services system analysis study. Volume 2: Satellite and services user model

NASA Technical Reports Server (NTRS)

1981-01-01

Satellite services needs are analyzed. Topics include methodology: a satellite user model; representative servicing scenarios; potential service needs; manned, remote, and automated involvement; and inactive satellites/debris. Satellite and services user model development is considered. Groundrules and assumptions, servicing, events, and sensitivity analysis are included. Selection of references satellites is also discussed.

An Historical Overview of the Production Requirement for the Satellite Technology Demonstration. Technical Report No. 0504.

ERIC Educational Resources Information Center

Smith, Myron P.; Sosey, Phillip

The Satellite Technology Demonstration employs the latest telecommunications technology to deliver community oriented programing to rural areas. To meet the demand for contemporary broadcasts responsive to community needs, a studio was constructed in the Denver area to produce and coordinate future programs for the Rocky Mountains area. Problems…

Satellite videoconferencing for healthcare workers: audience characteristics and the importance of continuing education credits.

PubMed

Chen, I L; Eckhardt, J N; Sinkowitz-Cochran, R L; Jarvis, W R

1999-11-01

To assess the opinions of healthcare workers (HCWs) about a satellite videoconference as a means of earning continuing education credit, a telephone survey was conducted in September 1998, 1 month after a live interactive satellite videoconference on antimicrobial use and resistance. There were 180 registered sites in 45 states surveyed, representing 1,589 viewers: 764 nurses (48.1%), 201 physicians (12.6%), and 624 other HCWs (39.3%). Continuing education credit was requested by 51% of nurses, 31% of physicians, and 27% of all other HCWs. Although preferred learning formats varied, 70% of respondents said it was important to offer continuing education credit. Furthermore, 31% of the respondents stated that the videoconference influenced institutional strategies. We concluded that satellite videoconferences are a method to reach audiences around the world efficiently and effectively, provide the latest information, facilitate interaction, and meet some of the demand for continuing education credit for HCWs.

Outer planets satellites

NASA Technical Reports Server (NTRS)

Morrison, D.

1983-01-01

The present investigation takes into account the published literature on outer planet satellites for 1979-1982. It is pointed out that all but three (the moon and the two Martian satellites) of the known planetary satellites are found in the outer solar system. Most of these are associated with the three regular satellite systems of Jupiter, Saturn, and Uranus. The largest satellites are Titan in the Saturn system and Ganymede and Callisto in the Jupiter system. Intermediate in size between Mercury and Mars, each has a diameter of about 5000 km. Presumably each has an internal composition about 60 percent rock and 40 ice, and each is differentiated with a dense core extending out about 75 percent of the distance to the surface, with a mantle of high-pressure ice and a crust of ordinary ice perhaps 100 km thick. Attention is also given to Io, Europa, the icy satellites of Saturn, the satellites of Uranus, the small satellites of Jupiter and Saturn, Triton and the Pluto system, and plans for future studies.

An evaluation of the use of ERTS-1 satellite imagery for grizzly bear habitat analysis

NASA Technical Reports Server (NTRS)

Varney, J. R.; Craighead, J. J.; Sumner, J.

1973-01-01

Multispectral scanner images taken by the ERTS-1 satellite in August and October, 1972, were examined to determine if they would be useful in identifying and mapping favorable habitat for grizzly bears. It was possible to identify areas having a suitable mixture of alpine meadow and timber, and to eliminate those which did not meet the isolation requirements of grizzlies because of farming or grazing activity. High altitude timbered areas mapped from satellite imagery agreed reasonably well with the distribution of whitebark pine, an important food species. Analysis of satellite imagery appears to be a valuable supplement to present ground observation methods, since it allows the most important areas to be identified for intensive study and many others to be eliminated from consideration. A sampling plan can be developed from such data which will minimize field effort and overall program cost.

Summary of the 2017 Alcohol and Immunology Research Interest Group (AIRIG) meeting.

PubMed

Hulsebus, Holly J; Curtis, Brenda J; Molina, Patricia E; Afshar, Majid; Boule, Lisbeth A; Morris, Niya; Keshavarzian, Ali; Kolls, Jay K; Yeligar, Samantha M; Price, Michael E; Wyatt, Todd A; Choudhry, Mashkoor A; Kovacs, Elizabeth J

2018-06-01

On June 24, 2017, the 22nd annual Alcohol and Immunology Research Interest Group (AIRIG) meeting was held as a satellite conference during the annual Research Society on Alcoholism (RSA) Scientific Meeting in Denver, Colorado. The 2017 meeting focused broadly on mechanisms that link alcohol to tissue injury and inflammation, and how this research can be translated to improve human health. Two plenary sessions composed the meeting, which first explored the association between alcohol and trauma/tissue injury, and finished with a discussion of alcohol and mucosal inflammation. The presentations encompassed diverse areas of alcohol research, from effects on the brain, to airway and pulmonary systems, to gut barrier disruption. The discussions also thoughtfully highlighted how current laboratory and clinical research can be used to prevent or treat alcohol-related morbidity and mortality. Copyright © 2017 Elsevier Inc. All rights reserved.

Concepts for on-board satellite image registration. Volume 3: Impact of VLSI/VHSIC on satellite on-board signal processing

NASA Technical Reports Server (NTRS)

Aanstoos, J. V.; Snyder, W. E.

1981-01-01

Anticipated major advances in integrated circuit technology in the near future are described as well as their impact on satellite onboard signal processing systems. Dramatic improvements in chip density, speed, power consumption, and system reliability are expected from very large scale integration. Improvements are expected from very large scale integration enable more intelligence to be placed on remote sensing platforms in space, meeting the goals of NASA's information adaptive system concept, a major component of the NASA End-to-End Data System program. A forecast of VLSI technological advances is presented, including a description of the Defense Department's very high speed integrated circuit program, a seven-year research and development effort.

Numerical modeling of the radionuclide water pathway with HYDRUS and comparison with the IAEA model of SR 44.

PubMed

Merk, Rainer

2012-02-01

This study depicts a theoretical experiment in which the radionuclide transport through the porous material of a landfill consisting of concrete rubble (e.g., from the decommissioning of nuclear power plants) and the subsequent migration through the vadose zone and aquifer to a model well is calculated by means of the software HYDRUS-1D (Simunek et al., 2008). The radionuclides originally contained within the rubble become dissolved due to leaching caused by infiltrated rainwater. The resulting well-water contamination (in Bq/L) is calculated numerically as a function of time and location and compared with the outcome of a simplified analytic model for the groundwater pathway published by the IAEA (2005). Identical model parameters are considered. The main objective of the present work is to evaluate the predictive capacity of the more simple IAEA model using HYDRUS-1D as a reference. For most of the radionuclides considered (e.g., ¹²⁹I, and ²³⁹Pu), results from applying the IAEA model were found to be comparable to results from the more elaborate HYDRUS modeling, provided the underlying parameter values are comparable. However, the IAEA model appears to underestimate the effects resulting from, for example, high nuclide mobility, short half-life, or short-term variations in the water infiltration. The present results indicate that the IAEA model is suited for screening calculations and general recommendation purposes. However, the analysis of a specific site should be accompanied by detailed HYDRUS computer simulations. In all models considered, the calculation outcome largely depends on the choice of the sorption parameter K(d). Copyright © 2011 Elsevier Ltd. All rights reserved.

Satellite -Based Networks for U-Health & U-Learning

NASA Astrophysics Data System (ADS)

Graschew, G.; Roelofs, T. A.; Rakowsky, S.; Schlag, P. M.

2008-08-01

The use of modern Information and Communication Technologies (ICT) as enabling tools for healthcare services (eHealth) introduces new ways of creating ubiquitous access to high-level medical care for all, anytime and anywhere (uHealth). Satellite communication constitutes one of the most flexible methods of broadband communication offering high reliability and cost-effectiveness of connections meeting telemedicine communication requirements. Global networks and the use of computers for educational purposes stimulate and support the development of virtual universities for e-learning. Especially real-time interactive applications can play an important role in tailored and personalised services.

27th Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

NASA Technical Reports Server (NTRS)

Sydnor, Richard L. (Editor)

1996-01-01

This document is a compilation of technical papers presented at the 27th Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting, held November 29 - December 1, 1995 at San Diego, CA. Papers are in the following categories: Recent developments in rubidium, cesium, and hydrogen-based frequency standards; and in cryogenic and trapped-ion technology; International and transnational applications of PTTI technology with emphasis on satellite laser tracking, GLONASS timing, intercomparison of national time scales and international telecommunications; Applications of PTTI technology to the telecommunications, power distribution, platform positioning, and geophysical survey industries; Applications of PTTI technology to evolving military communications and navigation systems; and Dissemination of precise time and frequency by means of Global Positioning System (GPS), Global Satellite Navigation System (GLONASS), MILSTAR, LORAN, and synchronous communications satellites.

Galileo satellite antenna modeling

NASA Astrophysics Data System (ADS)

Steigenberger, Peter; Dach, Rolf; Prange, Lars; Montenbruck, Oliver

2015-04-01

The space segment of the European satellite navigation system Galileo currently consists of six satellites. Four of them belong to the first generation of In-Orbit Validation (IOV) satellites whereas the other two are Full Operational Capability (FOC) satellites. High-precision geodetic applications require detailed knowledge about the actual phase center of the satellite and receiver antenna. The deviation of this actual phase center from a well-defined reference point is described by phase center offsets (PCOs) and phase center variations (PCVs). Unfortunately, no public information is available about the Galileo satellite antenna PCOs and PCVs, neither for the IOV, nor the FOC satellites. Therefore, conventional values for the IOV satellite antenna PCOs have been adopted for the Multi-GNSS experiment (MGEX) of the International GNSS Service (IGS). The effect of the PCVs is currently neglected and no PCOs for the FOC satellites are available yet. To overcome this deficiency in GNSS observation modeling, satellite antenna PCOs and PCVs are estimated for the Galileo IOV satellites based on global GNSS tracking data of the MGEX network and additional stations of the legacy IGS network. Two completely independent solutions are computed with the Bernese and Napeos software packages. The PCO and PCV values of the individual satellites are analyzed and the availability of two different solutions allows for an accuracy assessment. The FOC satellites are built by a different manufacturer and are also equipped with another type of antenna panel compared to the IOV satellites. Signal transmission of the first FOC satellite has started in December 2014 and activation of the second satellite is expected for early 2015. Based on the available observations PCO estimates and, optionally PCVs of the FOC satellites will be presented as well. Finally, the impact of the new antenna model on the precision and accuracy of the Galileo orbit determination is analyzed.

Satellite Vulnerabilities

DTIC Science & Technology

2008-02-18

allies. 8  Satellites and Intelligence , Surveillance, and Reconnaissance We have become dependent also on our satellite surveillance assets...uninterrupted ISR”, with “space intelligence , surveillance, and reconnaissance (ISR) systems…fundamental to air power—especially to the execution...tremendous informational and intelligence advantage. But if we lose those satellites, or the links to them, we also lose the advantages of them, and

The evolution and impact of the International Atomic Energy Agency (IAEA) program on radiation and tissue banking in Asia and the Pacific region.

PubMed

Morales Pedraza, Jorge; Phillips, Glyn O

2009-05-01

The Asia and the Pacific region was within the IAEA program on radiation and tissue banking, the most active region. Most of the tissue banks in the Asia and the Pacific region were developed during the late 1980s and 1990s. The initial number of tissue banks established or supported by the IAEA program in the framework of the RCA Agreement for Asia and the Pacific region was 18. At the end of 2006, the number of tissue banks participating, in one way or another in the IAEA program was 59. Since the beginning of the implementation of the IAEA program in Asia and the Pacific region 63,537 amnion and 44,282 bone allografts were produced and 57,683 amnion and 36,388 bone allografts were used. The main impact of the IAEA program in the region was the following: the establishment or consolidation of at least 59 tissue banks in 15 countries in the region (the IAEA supported directly 16 of these banks); the improvement on the quality and safety of tissues procured and produced in the region reaching international standards; the implementation of eight national projects, two regional projects and two interregional projects; the elaboration of International Standards, a Code of Practice and a Public Awareness Strategies and, the application of quality control and quality assurances programs in all participating tissue banks.

Satellite Data Simulator Unit: A Multisensor, Multispectral Satellite Simulator Package

NASA Technical Reports Server (NTRS)

Masunaga, Hirohiko; Matsui, Toshihisa; Tao, Wei-Kuo; Hou, Arthur Y.; Kummerow, Christian D.; Nakajima, Teruyuki; Bauer, Peter; Olson, William S.; Sekiguchi, Miho; Nakajima, Teruyuki

2010-01-01

Several multisensor simulator packages are being developed by different research groups across the world. Such simulator packages [e.g., COSP , CRTM, ECSIM, RTTO, ISSARS (under development), and SDSU (this article), among others] share overall aims, although some are targeted more on particular satellite programs or specific applications (for research purposes or for operational use) than others. The SDSU or Satellite Data Simulator Unit is a general-purpose simulator composed of Fortran 90 codes and applicable to spaceborne microwave radiometer, radar, and visible/infrared imagers including, but not limited to, the sensors listed in a table. That shows satellite programs particularly suitable for multisensor data analysis: some are single satellite missions carrying two or more instruments, while others are constellations of satellites flying in formation. The TRMM and A-Train are ongoing satellite missions carrying diverse sensors that observe clouds and precipitation, and will be continued or augmented within the decade to come by future multisensor missions such as the GPM and Earth-CARE. The ultimate goals of these present and proposed satellite programs are not restricted to clouds and precipitation but are to better understand their interactions with atmospheric dynamics/chemistry and feedback to climate. The SDSU's applicability is not technically limited to hydrometeor measurements either, but may be extended to air temperature and humidity observations by tuning the SDSU to sounding channels. As such, the SDSU and other multisensor simulators would potentially contribute to a broad area of climate and atmospheric sciences. The SDSU is not optimized to any particular orbital geometry of satellites. The SDSU is applicable not only to low-Earth orbiting platforms as listed in Table 1, but also to geostationary meteorological satellites. Although no geosynchronous satellite carries microwave instruments at present or in the near future, the SDSU would be

Earth-viewing satellite perspectives on the Chelyabinsk meteor event.

PubMed

Miller, Steven D; Straka, William C; Bachmeier, A Scott; Schmit, Timothy J; Partain, Philip T; Noh, Yoo-Jeong

2013-11-05

Large meteors (or superbolides [Ceplecha Z, et al. (1999) Meteoroids 1998:37-54]), although rare in recorded history, give sobering testimony to civilization's inherent vulnerability. A not-so-subtle reminder came on the morning of February 15, 2013, when a large meteoroid hurtled into the Earth's atmosphere, forming a superbolide near the city of Chelyabinsnk, Russia, ∼1,500 km east of Moscow, Russia [Ivanova MA, et al. (2013) Abstracts of the 76th Annual Meeting of the Meteoritical Society, 5366]. The object exploded in the stratosphere, and the ensuing shock wave blasted the city of Chelyabinsk, damaging structures and injuring hundreds. Details of trajectory are important for determining its specific source, the likelihood of future events, and potential mitigation measures. Earth-viewing environmental satellites can assist in these assessments. Here we examine satellite observations of the Chelyabinsk superbolide debris trail, collected within minutes of its entry. Estimates of trajectory are derived from differential views of the significantly parallax-displaced [e.g., Hasler AF (1981) Bull Am Meteor Soc 52:194-212] debris trail. The 282.7 ± 2.3° azimuth of trajectory, 18.5 ± 3.8° slope to the horizontal, and 17.7 ± 0.5 km/s velocity derived from these satellites agree well with parameters inferred from the wealth of surface-based photographs and amateur videos. More importantly, the results demonstrate the general ability of Earth-viewing satellites to provide valuable insight on trajectory reconstruction in the more likely scenario of sparse or nonexistent surface observations.

Earth-viewing satellite perspectives on the Chelyabinsk meteor event

PubMed Central

Miller, Steven D.; Straka, William C.; Bachmeier, A. Scott; Schmit, Timothy J.; Partain, Philip T.; Noh, Yoo-Jeong

2013-01-01

Large meteors (or superbolides [Ceplecha Z, et al. (1999) Meteoroids 1998:37–54]), although rare in recorded history, give sobering testimony to civilization’s inherent vulnerability. A not-so-subtle reminder came on the morning of February 15, 2013, when a large meteoroid hurtled into the Earth’s atmosphere, forming a superbolide near the city of Chelyabinsnk, Russia, ∼1,500 km east of Moscow, Russia [Ivanova MA, et al. (2013) Abstracts of the 76th Annual Meeting of the Meteoritical Society, 5366]. The object exploded in the stratosphere, and the ensuing shock wave blasted the city of Chelyabinsk, damaging structures and injuring hundreds. Details of trajectory are important for determining its specific source, the likelihood of future events, and potential mitigation measures. Earth-viewing environmental satellites can assist in these assessments. Here we examine satellite observations of the Chelyabinsk superbolide debris trail, collected within minutes of its entry. Estimates of trajectory are derived from differential views of the significantly parallax-displaced [e.g., Hasler AF (1981) Bull Am Meteor Soc 52:194–212] debris trail. The 282.7 ± 2.3° azimuth of trajectory, 18.5 ± 3.8° slope to the horizontal, and 17.7 ± 0.5 km/s velocity derived from these satellites agree well with parameters inferred from the wealth of surface-based photographs and amateur videos. More importantly, the results demonstrate the general ability of Earth-viewing satellites to provide valuable insight on trajectory reconstruction in the more likely scenario of sparse or nonexistent surface observations. PMID:24145398

A review of the International Atomic Energy Agency (IAEA) international standards for tissue banks.

PubMed

Morales Pedraza, Jorge; Lobo Gajiwala, Astrid; Martinez Pardo, María Esther

2012-03-01

The IAEA International Standards for Tissue Banks published in 2003 were based on the Standards then currently in use in the USA and the European Union, among others, and reflect the best practices associated with the operation of a tissue bank. They cover legal, ethical and regulatory controls as well as requirements and procedures from donor selection and tissue retrieval to processing and distribution of finished tissue for clinical use. The application of these standards allows tissue banks to operate with the current good tissue practice, thereby providing grafts of high quality that satisfy the national and international demand for safe and biologically useful grafts. The objective of this article is to review the IAEA Standards and recommend new topics that could improve the current version.

Current Trends and Challenges in Satellite Laser Ranging

NASA Astrophysics Data System (ADS)

Appleby, Graham M.; Bianco, Giuseppe; Noll, Carey E.; Pavlis, Erricos C.; Pearlman, Michael R.

2016-12-01

Satellite Laser Ranging (SLR) is used to measure accurately the distance from ground stations to retro-reflectors on satellites and on the Moon. SLR is one of the fundamental space-geodetic techniques that define the International Terrestrial Reference Frame (ITRF), which is the basis upon which many aspects of global change over space, time, and evolving technology are measured; with VLBI the two techniques define the scale of the ITRF; alone the SLR technique defines its origin (geocenter). The importance of the reference frame has recently been recognized at the inter-governmental level through the United Nations, which adopted in February 2015 the Resolution "Global Geodetic Reference Frame for Sustainable Development." Laser Ranging provides precision orbit determination and instrument calibration and validation for satellite-borne altimeters for the better understanding of sea level change, ocean dynamics, ice mass-balance, and terrestrial topography. It is also a tool to study the dynamics of the Moon and fundamental constants and theories. With the exception of the currently in-orbit GPS constellation, all GNSS satellites now carry retro-reflectors for improved orbit determination, harmonization of reference frames, and in-orbit co-location and system performance validation; the next generation of GPS satellites due for launch from 2019 onwards will also carry retro-reflectors. The ILRS delivers weekly realizations that are accumulated sequentially to extend the ITRF and the Earth Orientation Parameter series with a daily resolution. SLR technology continues to evolve towards the next-generation laser ranging systems and it is expected to successfully meet the challenges of the GGOS2020 program for a future Global Space Geodetic Network. Ranging precision is improving as higher repetition rate, narrower pulse lasers, and faster detectors are implemented within the network. Automation and pass interleaving at some stations is expanding temporal coverage and

Satellite Instrument Calibration for Measuring Global Climate Change. Report of a Workshop at the University of Maryland Inn and Conference Center, College Park, MD. , November 12-14, 2002

NASA Technical Reports Server (NTRS)

Ohring, G.; Wielicki, B.; Spencer, R.; Emery, B.; Datla, R.

2004-01-01

Measuring the small changes associated with long-term global climate change from space is a daunting task. To address these problems and recommend directions for improvements in satellite instrument calibration some 75 scientists, including researchers who develop and analyze long-term data sets from satellites, experts in the field of satellite instrument calibration, and physicists working on state of the art calibration sources and standards met November 12 - 14, 2002 and discussed the issues. The workshop defined the absolute accuracies and long-term stabilities of global climate data sets that are needed to detect expected trends, translated these data set accuracies and stabilities to required satellite instrument accuracies and stabilities, and evaluated the ability of current observing systems to meet these requirements. The workshop's recommendations include a set of basic axioms or overarching principles that must guide high quality climate observations in general, and a roadmap for improving satellite instrument characterization, calibration, inter-calibration, and associated activities to meet the challenge of measuring global climate change. It is also recommended that a follow-up workshop be conducted to discuss implementation of the roadmap developed at this workshop.

IP voice over ATM satellite: experimental results over satellite channels

NASA Astrophysics Data System (ADS)

Saraf, Koroush A.; Butts, Norman P.

1999-01-01

IP telephony, a new technology to provide voice communication over traditional data networks, has the potential to revolutionize telephone communication within the modern enterprise. This innovation uses packetization techniques to carry voice conversations over IP networks. This packet switched technology promises new integrated services, and lower cost long-distance communication compared to traditional circuit switched telephone networks. Future satellites will need to carry IP traffic efficiently in order to stay competitive in servicing the global data- networking and global telephony infrastructure. However, the effects of Voice over IP over switched satellite channels have not been investigated in detail. To fully understand the effects of satellite channels on Voice over IP quality; several experiments were conducted at Lockheed Martin Telecommunications' Satellite Integration Lab. The result of those experiments along with suggested improvements for voice communication over satellite are presented in this document. First, a detailed introduction of IP telephony as a suitable technology for voice communication over future satellites is presented. This is followed by procedures for the experiments, along with results and strategies. In conclusion we hope that these capability demonstrations will alleviate any uncertainty regarding the applicability of this technology to satellite networks.

CONFERENCE REPORT: Summary of the 8th IAEA Technical Meeting on Fusion Power Plant Safety

NASA Astrophysics Data System (ADS)

Girard, J. Ph.; Gulden, W.; Kolbasov, B.; Louzeiro-Malaquias, A.-J.; Petti, D.; Rodriguez-Rodrigo, L.

2008-01-01

for materials selection which will have a large impact on waste disposal and recycling and in the real limits of radiation releases if indexed to the real impact on individuals and the environment given the differences in the types of radiation emitted by tritium when compared with the fission products. Round table sessions resulted in some common recommendations. The discussions also created the awareness of the need for a larger involvement of the IAEA in support of fusion safety standards development.

Small satellites

NASA Technical Reports Server (NTRS)

Thomas, P.; Veverka, J.; Dermott, S.

1986-01-01

Satellites smaller than Mimas (r = 195 km) are distinguished by irregular overall shapes and by rough limb topography. Material properties and impact cratering dominate the shaping of these objects. Long fragmentation histories can produce a variety of internal structures, but so far there is no direct evidence that any small satellite is an equilibrium ellipsoid made up of noncohesive gravitationally bound rubble. One many bodies that orbit close to their primary the tidal and rotational components of surface gravity strongly affect the directions of local g and thereby affect the redistribution of regolith by mass wasting. Downslope movement of regolith is extensive on Deimos, and is probably effective on many other small satellites. It is shown that in some cases observed patterns of downslope mass wasting cold produce useful constraints on the satellite's mean density. The diversity of features seen in the few high-resolution images of small satellites currently available suggests that these objects have undergone complex histories of cratering, fragmentation, and regolith evolution.

Small optical inter-satellite communication system for small and micro satellites

NASA Astrophysics Data System (ADS)

Iwamoto, Kyohei; Nakao, Takashi; Ito, Taiji; Sano, Takeshi; Ishii, Tamotsu; Shibata, Keiichi; Ueno, Mitsuhiro; Ohta, Shinji; Komatsu, Hiromitsu; Araki, Tomohiro; Kobayashi, Yuta; Sawada, Hirotaka

2017-02-01

Small optical inter-satellite communication system to be installed into small and micro satellites flying on LEO are designed and experimentally verified of its fundamental functions. Small, light weighted, power efficient as well as usable data transmission rate optical inter-satellite communication system is one of promising approach to provide realtime data handling and operation capabilities for micro and small satellite constellations which have limited conditions of payload. Proposed system is designed to connect satellites with 4500 (km) long maximum to be able to talk with ground station continuously by relaying LEO satellites even when they are in their own maneuvers. Connecting satellites with 4500 (km) long with keeping steady data rate, accurate pointing and tracking method will be one of a crucial issue. In this paper, we propose a precious pointing and tracking method and system with a miniature optics and experimentally verified almost 10 (μrad) of pointing accuracy with more than 500 (mrad) of angular coverage.

The 18 and 30 GHz fixed service communication satellite system study: Executive summary

NASA Technical Reports Server (NTRS)

Bronstein, L. M.

1979-01-01

The use of the 18 and 30 GHz bands for fixed service satellite communications is examined. Primary objectives were to determine if satellite communication systems using this allocation (27.5 to 30.0 GHz uplink; 17.7 to 20.2 GHz downlink) can be cost competitive with alternate means of communication, and to determine what technological developments would be required to make these systems competitive. To meet these objectives, the cost and performance to be expected of 18 and 30 GHz hardware in the 1985 to 1990 era was assessed, selected trunking and direct to user concepts were optimized, and the cost of these systems was estimated. Finally, the technology developments required to make the most promising of the concepts competitive were identified.

Enhanced Resources of the SMDC Monitoring Research Program for Source Information and Data Acquisition

DTIC Science & Technology

2007-09-01

Springer locations (red) with satellite imagery illustrating roundoff error in Springer locations (b). Comparison of Rainier Mesa tunnel location of...Burrows et al.; Bolt; IAEA South Pacific Burrows et al.; Bolt; IAEA; AWE India Pokhran Gupta/Pabian; Norris/Arkin North Korea Mount Mantap Richards

Use of Satellite Data Assimilation to Infer Land Surface Thermal Inertia

NASA Technical Reports Server (NTRS)

Lapenta, William; McNider, Richard T.; Biazar, Arastoo; Suggs, Ron; Jedlovec, Gary; Dembek, Scott

2002-01-01

There are two important but observationally uncertain parameters in the grid averaged surface energy budgets of mesoscale models - surface moisture availability and thermal heat capacity. A technique has been successfully developed for assimilating Geostationary Operational Environmental Satellite (GOES) skin temperature tendencies during the mid-morning time frame to improve specification of surface moisture. In a new application of the technique, the use of satellite skin temperature tendencies in early evening is explored to improve specification of the surface thermal heat capacity. Together, these two satellite assimilation constraints have been shown to significantly improve the characterization of the surface energy budget of a mesoscale model on fine spatial scales. The GOES assimilation without the adjusted heat capacity was run operationally during the International H2O Project on a 12-km grid. This paper presents the results obtained when using both the moisture availability and heat capacity retrievals in concert. Preliminary results indicate that retrieved moisture availability alone improved the verification statistics of 2-meter temperature and dew point forecasts. Results from the 1.5 month long study period using the bulk heat capacity will be presented at the meeting.

Joint Polar Satellite System (JPSS) Common Ground System (CGS) Architecture Overview and Technical Performance Measures

NASA Astrophysics Data System (ADS)

Grant, K. D.; Johnson, B. R.; Miller, S. W.; Jamilkowski, M. L.

2014-12-01

The National Oceanic and Atmospheric Administration (NOAA) and National Aeronautics and Space Administration (NASA) are jointly acquiring the next-generation civilian weather and environmental satellite system: the Joint Polar Satellite System (JPSS). The Joint Polar Satellite System will replace the afternoon orbit component and ground processing system of the current Polar-orbiting Operational Environmental Satellites (POES) managed by NOAA. The JPSS satellites will carry a suite of sensors designed to collect meteorological, oceanographic, climatological and geophysical observations of the Earth. The ground processing system for JPSS is known as the JPSS Common Ground System (JPSS CGS). Developed and maintained by Raytheon Intelligence, Information and Services (IIS), the CGS is a multi-mission enterprise system serving NOAA, NASA and their national and international partners. The CGS provides a wide range of support to a number of missions. Originally designed to support S-NPP and JPSS, the CGS has demonstrated its scalability and flexibility to incorporate all of these other important missions efficiently and with minimal cost, schedule and risk, while strengthening global partnerships in weather and environmental monitoring. The CGS architecture will be upgraded to Block 2.0 in 2015 to satisfy several key objectives, including: "operationalizing" S-NPP, which had originally been intended as a risk reduction mission; leveraging lessons learned to date in multi-mission support; taking advantage of newer, more reliable and efficient technologies; and satisfying new requirements and constraints due to the continually evolving budgetary environment. To ensure the CGS meets these needs, we have developed 48 Technical Performance Measures (TPMs) across 9 categories: Data Availability, Data Latency, Operational Availability, Margin, Scalability, Situational Awareness, Transition (between environments and sites), WAN Efficiency, and Data Recovery Processing. This

Time synchronization of new-generation BDS satellites using inter-satellite link measurements

NASA Astrophysics Data System (ADS)

Pan, Junyang; Hu, Xiaogong; Zhou, Shanshi; Tang, Chengpan; Guo, Rui; Zhu, Lingfeng; Tang, Guifeng; Hu, Guangming

2018-01-01

Autonomous satellite navigation is based on the ability of a Global Navigation Satellite System (GNSS), such as Beidou, to estimate orbits and clock parameters onboard satellites using Inter-Satellite Link (ISL) measurements instead of tracking data from a ground monitoring network. This paper focuses on the time synchronization of new-generation Beidou Navigation Satellite System (BDS) satellites equipped with an ISL payload. Two modes of Ka-band ISL measurements, Time Division Multiple Access (TDMA) mode and the continuous link mode, were used onboard these BDS satellites. Using a mathematical formulation for each measurement mode along with a derivation of the satellite clock offsets, geometric ranges from the dual one-way measurements were introduced. Then, pseudoranges and clock offsets were evaluated for the new-generation BDS satellites. The evaluation shows that the ranging accuracies of TDMA ISL and the continuous link are approximately 4 cm and 1 cm (root mean square, RMS), respectively. Both lead to ISL clock offset residuals of less than 0.3 ns (RMS). For further validation, time synchronization between these satellites to a ground control station keeping the systematic time in BDT was conducted using L-band Two-way Satellite Time Frequency Transfer (TWSTFT). System errors in the ISL measurements were calibrated by comparing the derived clock offsets with the TWSTFT. The standard deviations of the estimated ISL system errors are less than 0.3 ns, and the calibrated ISL clock parameters are consistent with that of the L-band TWSTFT. For the regional BDS network, the addition of ISL measurements for medium orbit (MEO) BDS satellites increased the clock tracking coverage by more than 40% for each orbital revolution. As a result, the clock predicting error for the satellite M1S was improved from 3.59 to 0.86 ns (RMS), and the predicting error of the satellite M2S was improved from 1.94 to 0.57 ns (RMS), which is a significant improvement by a factor of 3-4.

Advanced communication satellites worldwide - Satellites of opportunity for the ACTS mobile terminal

NASA Technical Reports Server (NTRS)

Girardey, Catherine C.

1993-01-01

Space agencies worldwide are involved in advanced satellite communication systems. This paper presents an overview of these satellites and related technologies in the U.S., Europe, and Japan. They are geostationary satellites using high frequency bands such as K/Ka (20/30 GHz) and O-band (millimeter wave), as well as optical frequencies. The similarity of these programs demonstrate a common interest to develop large capacity satellite communication systems, and shows that closer international cooperation could be set up. The ACTS Mobile Terminal (AMT) project discussed here is such an example. The AMT's compatibility with satellites other than ACTS has been studied, and a proposed common experiment is presented here. The Japanese Engineering Test Satellite ETS-VI has been identified as the best initial 'satellite of opportunity' for AMT in this preliminary assessment.

Meteorological Measurements from Satellite Platforms. [stability and control of flexible stochastic satellites

NASA Technical Reports Server (NTRS)

Suomi, V. E.

1975-01-01

The stability of stochastic satellites and the stability and control of flexible satellites were investigated. The effects of random environmental torques and noises in the moments of inertia of spinning and three-axes stabilized satellites were first compared analytically by four methods and by analog simulations. Among the analytical methods, it was shown that the Fokker-Planck formulation yields predictions which most coincide with the simulation results. It was then shown that the required stability criterion of a satellite is quite different from that obtained by a deterministic approach, under the assumption that the environmental and control torques experienced by the satellite are random. Finally, it was demonstrated that, by monitoring the deformations of the flexible elements of a satellite, the effectiveness of the satellite control system can be increased considerably.

GOES West - Western Region WFO Satellite Imagery - Satellite Products and

Science.gov Websites

Services Division - Office of Satellite and Product Operations Skip Navigation Link NESDIS banner image and link to NESDIS link to the NOAA Home page Link to the National Environmental Satellite , Data, and Information Service Home Page Default Office of Satellite and Product Operations banner image

Department of Energy Efforts to Promote Universal Adherence to the IAEA Additional Protocol

DOE Office of Scientific and Technical Information (OSTI.GOV)

Killinger, Mark H.; Hansen, Linda H.; Kovacic, Don N.

2009-10-06

Entry-into-force of the U.S. Additional Protocol (AP) in January 2009 continues to demonstrate the ongoing commitment by the United States to promote universal adherence to the AP. The AP is a critical tool for improving the International Atomic Energy Agency’s (IAEA) capabilities to detect undeclared activities that indicate a clandestine nuclear weapons program. This is because States Parties are required to provide information about, and access to, nuclear fuel cycle activities beyond their traditional safeguards reporting requirements. As part of the U.S. AP Implementation Act and Senate Resolution of Ratification, the Administration is required to report annually to Congress onmore » measures taken to achieve the adoption of the AP in non-nuclear weapon states, as well as assistance to the IAEA to promote the effective implementation of APs in those states. A key U.S. effort in this area is being managed by the International Nuclear Safeguards and Engagement Program (INSEP) of the U.S. Department of Energy (DOE). Through new and existing bilateral cooperation agreements, INSEP has initiated technical assistance projects for AP implementation with selected non-weapon states. States with which INSEP is currently cooperating include Vietnam and Thailand, with Indonesia, Algeria, Morocco, and other countries as possible future collaborators in the area of AP implementation. The INSEP collaborative model begins with a joint assessment with our partners to identify specific needs they may have regarding entering the AP into force and any impediments to successful implementation. An action plan is then developed detailing and prioritizing the necessary joint activities. Such assistance may include: advice on developing legal frameworks and regulatory documents; workshops to promote understanding of AP requirements; training to determine possible declarable activities; assistance in developing a system to collect and submit declarations; performing industry

Satellite Derived Volcanic Ash Product Inter-Comparison in Support to SCOPE-Nowcasting

NASA Astrophysics Data System (ADS)

Siddans, Richard; Thomas, Gareth; Pavolonis, Mike; Bojinski, Stephan

2016-04-01

In support of aeronautical meteorological services, WMO organized a satellite-based volcanic ash retrieval algorithm inter-comparison activity, to improve the consistency of quantitative volcanic ash products from satellites, under the Sustained, Coordinated Processing of Environmental Satellite Data for Nowcasting (SCOPEe Nowcasting) initiative (http:/ jwww.wmo.int/pagesjprogjsatjscopee nowcasting_en.php). The aims of the intercomparison were as follows: 1. Select cases (Sarychev Peak 2009, Eyjafyallajökull 2010, Grimsvötn 2011, Puyehue-Cordón Caulle 2011, Kirishimayama 2011, Kelut 2014), and quantify the differences between satellite-derived volcanic ash cloud properties derived from different techniques and sensors; 2. Establish a basic validation protocol for satellite-derived volcanic ash cloud properties; 3. Document the strengths and weaknesses of different remote sensing approaches as a function of satellite sensor; 4. Standardize the units and quality flags associated with volcanic cloud geophysical parameters; 5. Provide recommendations to Volcanic Ash Advisory Centers (VAACs) and other users on how to best to utilize quantitative satellite products in operations; 6. Create a "road map" for future volcanic ash related scientific developments and inter-comparison/validation activities that can also be applied to SO2 clouds and emergent volcanic clouds. Volcanic ash satellite remote sensing experts from operational and research organizations were encouraged to participate in the inter-comparison activity, to establish the plans for the inter-comparison and to submit data sets. RAL was contracted by EUMETSAT to perform a systematic inter-comparison of all submitted datasets and results were reported at the WMO International Volcanic Ash Inter-comparison Meeting to held on 29 June - 2 July 2015 in Madison, WI, USA (http:/ /cimss.ssec.wisc.edujmeetings/vol_ash14). 26 different data sets were submitted, from a range of passive imagers and spectrometers and

Satellite myths

NASA Astrophysics Data System (ADS)

Easton, Roger L.; Hall, David

2008-01-01

Richard Corfield's article “Sputnik's legacy” (October 2007 pp23-27) states that the satellite on board the US Vanguard rocket, which exploded during launch on 6 December 1957 two months after Sputnik's successful take-off, was “a hastily put together contraption of wires and circuitry designed only to send a radio signal back to Earth”. In fact, the Vanguard satellite was developed over a period of several years and put together carefully using the best techniques and equipment available at the time - such as transistors from Bell Laboratories/Western Electric. The satellite contained not one but two transmitters, in which the crystal-controlled oscillators had been designed to measure both the temperature of the satellite shell and of the internal package.

NOAASIS (NOAA Satellite Information System) Home Page - Office of Satellite

Science.gov Websites

and Product Operations » DOC » NOAA » NESDIS » NOAASIS NOAA Satellite Information System Organizational Links National Environmental Satellite, Data, and Information Service (NESDIS) Office of Satellite ): Information and specific ground project support data for the Direct Broadcast Community from JPSS supported

Communication satellite applications

NASA Astrophysics Data System (ADS)

Pelton, Joseph N.

The status and future of the technologies, numbers and services provided by communications satellites worldwide are explored. The evolution of Intelsat satellites and the associated earth terminals toward high-rate all-digital telephony, data, facsimile, videophone, videoconferencing and DBS capabilities are described. The capabilities, services and usage of the Intersputnik, Eutelsat, Arabsat and Palapa systems are also outlined. Domestic satellite communications by means of the Molniya, ANIK, Olympus, Intelsat and Palapa spacecraft are outlined, noting the fast growth of the market and the growing number of different satellite manufacturers. The technical, economic and service definition issues surrounding DBS systems are discussed, along with presently operating and planned maritime and aeronautical communications and positioning systems. Features of search and rescue and tracking, data, and relay satellite systems are summarized, and services offered or which will be offered by every existing or planned communication satellite worldwide are tabulated.

Survey: National Environmental Satellite Service

NASA Technical Reports Server (NTRS)

1977-01-01

The national Environmental Satellite Service (NESS) receives data at periodic intervals from satellites of the Synchronous Meteorological Satellite/Geostationary Operational Environmental Satellite series and from the Improved TIROS (Television Infrared Observational Satellite) Operational Satellite. Within the conterminous United States, direct readout and processed products are distributed to users over facsimile networks from a central processing and data distribution facility. In addition, the NESS Satellite Field Stations analyze, interpret, and distribute processed geostationary satellite products to regional weather service activities.

Ranging error analysis of single photon satellite laser altimetry under different terrain conditions

NASA Astrophysics Data System (ADS)

Huang, Jiapeng; Li, Guoyuan; Gao, Xiaoming; Wang, Jianmin; Fan, Wenfeng; Zhou, Shihong

2018-02-01

Single photon satellite laser altimeter is based on Geiger model, which has the characteristics of small spot, high repetition rate etc. In this paper, for the slope terrain, the distance of error's formula and numerical calculation are carried out. Monte Carlo method is used to simulate the experiment of different terrain measurements. The experimental results show that ranging accuracy is not affected by the spot size under the condition of the flat terrain, But the inclined terrain can influence the ranging error dramatically, when the satellite pointing angle is 0.001° and the terrain slope is about 12°, the ranging error can reach to 0.5m. While the accuracy can't meet the requirement when the slope is more than 70°. Monte Carlo simulation results show that single photon laser altimeter satellite with high repetition rate can improve the ranging accuracy under the condition of complex terrain. In order to ensure repeated observation of the same point for 25 times, according to the parameters of ICESat-2, we deduce the quantitative relation between the footprint size, footprint, and the frequency repetition. The related conclusions can provide reference for the design and demonstration of the domestic single photon laser altimetry satellite.

Compendium of meteorological satellites and instrumentation. [US, USSR, UK, and French satellites

NASA Technical Reports Server (NTRS)

Stoldt, N. W.; Havanac, P. J.

1973-01-01

Pertinent information is presented for 98 launched and planned satellites of the U.S., U.K., U.S.S.R., and France, as well as their over 200 meteorological experiments or instruments. Summary information is provided for both operational and research satellites. Three major sections include: (1) an overview by country, of the various series of meteorological satellite programs; (2) brief descriptions of the satellites and their experiments; and (3) an extensive bibliography. A glossary of acronyms and two indexes for cross-referencing are also included. In addition, various tables and figures presenting satellite operating times, data coverage, location of launch sites, and descriptions of the launch vehicles used to orbit the meteorological satellites are given.

Analysis of Terrestrial Interference Protection from UAS CNPC Satellite Transmitters

NASA Technical Reports Server (NTRS)

Kerczewski, Robert J.; Wilson, Jeffrey D.; Bishop, William D.

2016-01-01

Unmanned aircraft (UA) are projected to have a major impact on future aviation. Larger UA operating at altitudes above 3000 feet will require at least occasional access to non-segregated, that is, controlled airspace. In order for unmanned aircraft to be integrated into the airspace and operate with other commercial aircraft, a very reliable command and control (a. k. a. control and non-payload communications, (CNPC)) link is required. For operations covering large distances or over remote locations, a beyond-line-of-sight (BLOS) CNPC link implemented through a satellite will almost always be required. Protected aviation spectrum (aeronautical mobile satellite (route) service, or AMS(R)S) would normally be used for such a safety-critical link, however studies have shown that currently available aviation safety satellite spectrum is inadequate to support the projected BLOS CNPC link bandwidth requirements. To address this inadequacy, the 2015 World Radio communication Conference studied the possible use of the Fixed Satellite Service (FSS) to provide CNPC, including possible allocations in Ku-Band and Ka-Band, under Agenda Item (AI) 1.5. Although UA CNPC satellite links in these bands were shown to meet operational availability and continuity requirements, a serious complication exists in that there are also terrestrial service allocations in these bands, in particular, Fixed Service (FS) point-to-point and point-to-multipoint microwave digital links. During the WRC-15 study cycle, much opposition to AI 1.5 was generated based on fears that UA CNPC satellite transmitters in these bands would impose unacceptable levels of interference to the FS receivers. NASA analyzed the possible interference from the UA transmitters based on probable UA transmission and FS receiver characteristics, and UA traffic distributions and densities to determine conditions under which UA could operate without imposing unacceptable interference levels to the FS. Ultimately, UA power flux

Satellite Estimates of Surface Short-wave Fluxes: Issues of Implementation

NASA Technical Reports Server (NTRS)

Wang, H.; Pinker, Rachel; Minnis, Patrick

2006-01-01

Surface solar radiation reaching the Earth's surface is the primary forcing function of the land surface energy and water cycle. Therefore, there is a need for information on this parameter, preferably, at global scale. Satellite based estimates are now available at accuracies that meet the demands of many scientific objectives. Selection of an approach to estimate such fluxes requires consideration of trade-offs between the use of multi-spectral observations of cloud optical properties that are more difficult to implement at large scales, and methods that are simplified but easier to implement. In this study, an evaluation of such trade-offs will be performed. The University of Maryland Surface Radiation Model (UMD/SRB) has been used to reprocess five years of GOES-8 satellite observations over the United States to ensure updated calibration and improved cloud detection over snow. The UMD/SRB model was subsequently modified to allow input of information on aerosol and cloud optical depth with information from independent satellite sources. Specifically, the cloud properties from the Atmospheric Radiation Measurement (ARM) Satellite Data Analysis Program (Minnis et al., 1995) are used to drive the modified version of the model to estimate surface short-wave fluxes over the Southern Great Plain ARM sites for a twelve month period. The auxiliary data needed as model inputs such as aerosol optical depth, spectral surface albedo, water vapor and total column ozone amount were kept the same for both versions of the model. The estimated shortwave fluxes are evaluated against ground observations at the ARM Central Facility and four satellite ARM sites. During summer, the estimated fluxes based on cloud properties derived from the multi-spectral approach were in better agreement with ground measurements than those derived from the UMD/SRB model. However, in winter, the fluxes derived with the UMD/SRB model were in better agreement with ground observations than those

Ionospheric range-rate effects in satellite-to-satellite tracking

NASA Technical Reports Server (NTRS)

Lipofsky, J. R.; Bent, R. B.; Llewellyn, S. K.; Schmid, P. E.

1977-01-01

Investigation of ionospheric range and range-rate corrections in satellite-to-satellite tracking were investigated. Major problems were cited and the magnitude of errors that have to be considered for communications between satellites and related experiments was defined. The results point to the need of using a sophisticated modeling approach incorporating daily solar data, and where possible actual ionospheric measurements as update information, as a simple median model cannot possibly account for the complex interaction of the many variables. The findings provide a basis from which the residual errors can be estimated after ionospheric modeling is incorporated in the reduction. Simulations were performed for satellites at various heights: Apollo, Geos, and Nimbus tracked by ATS-6; and in two different geometric configurations: coplanar and perpendicular orbits.

Relative tracking control of constellation satellites considering inter-satellite link

NASA Astrophysics Data System (ADS)

Fakoor, M.; Amozegary, F.; Bakhtiari, M.; Daneshjou, K.

2017-11-01

In this article, two main issues related to the large-scale relative motion of satellites in the constellation are investigated to establish the Inter Satellite Link (ISL) which means the dynamic and control problems. In the section related to dynamic problems, a detailed and effective analytical solution is initially provided for the problem of satellite relative motion considering perturbations. The direct geometric method utilizing spherical coordinates is employed to achieve this solution. The evaluation of simulation shows that the solution obtained from the geometric method calculates the relative motion of the satellite with high accuracy. Thus, the proposed analytical solution will be applicable and effective. In the section related to control problems, the relative tracking control system between two satellites will be designed in order to establish a communication link between the satellites utilizing analytical solution for relative motion of satellites with respect to the reference trajectory. Sliding mode control approach is employed to develop the relative tracking control system for body to body and payload to payload tracking control. Efficiency of sliding mode control approach is compared with PID and LQR controllers. Two types of payload to payload tracking control considering with and without payload degree of freedom are designed and suitable one for practical ISL applications is introduced. Also, Fuzzy controller is utilized to eliminate the control input in the sliding mode controller.

Mobile satellite service communications tests using a NASA satellite

NASA Technical Reports Server (NTRS)

Chambers, Katherine H.; Koschmeder, Louis A.; Hollansworth, James E.; ONeill, Jack; Jones, Robert E.; Gibbons, Richard C.

1995-01-01

Emerging applications of commercial mobile satellite communications include satellite delivery of compact disc (CD) quality radio to car drivers who can select their favorite programming as they drive any distance; transmission of current air traffic data to aircraft; and handheld communication of data and images from any remote corner of the world. Experiments with the enabling technologies and tests and demonstrations of these concepts are being conducted before the first satellite is launched by utilizing an existing NASA spacecraft.

Interim Service ISDN Satellite (ISIS) simulator development for advanced satellite designs and experiments

NASA Technical Reports Server (NTRS)

Pepin, Gerard R.

1992-01-01

The simulation development associated with the network models of both the Interim Service Integrated Services Digital Network (ISDN) Satellite (ISIS) and the Full Service ISDN Satellite (FSIS) architectures is documented. The ISIS Network Model design represents satellite systems like the Advanced Communications Technology Satellite (ACTS) orbiting switch. The FSIS architecture, the ultimate aim of this element of the Satellite Communications Applications Research (SCAR) Program, moves all control and switching functions on-board the next generation ISDN communications satellite. The technical and operational parameters for the advanced ISDN communications satellite design will be obtained from the simulation of ISIS and FSIS engineering software models for their major subsystems. Discrete event simulation experiments will be performed with these models using various traffic scenarios, design parameters, and operational procedures. The data from these simulations will be used to determine the engineering parameters for the advanced ISDN communications satellite.

Application of constraint-based satellite mission planning model in forest fire monitoring

NASA Astrophysics Data System (ADS)

Guo, Bingjun; Wang, Hongfei; Wu, Peng

2017-10-01

In this paper, a constraint-based satellite mission planning model is established based on the thought of constraint satisfaction. It includes target, request, observation, satellite, payload and other elements, with constraints linked up. The optimization goal of the model is to make full use of time and resources, and improve the efficiency of target observation. Greedy algorithm is used in the model solving to make observation plan and data transmission plan. Two simulation experiments are designed and carried out, which are routine monitoring of global forest fire and emergency monitoring of forest fires in Australia. The simulation results proved that the model and algorithm perform well. And the model is of good emergency response capability. Efficient and reasonable plan can be worked out to meet users' needs under complex cases of multiple payloads, multiple targets and variable priorities with this model.

Accelerating vaccine development and deployment: report of a Royal Society satellite meeting

PubMed Central

Bregu, Migena; Draper, Simon J.; Hill, Adrian V. S.; Greenwood, Brian M.

2011-01-01

The Royal Society convened a meeting on the 17th and 18th November 2010 to review the current ways in which vaccines are developed and deployed, and to make recommendations as to how each of these processes might be accelerated. The meeting brought together academics, industry representatives, research sponsors, regulators, government advisors and representatives of international public health agencies from a broad geographical background. Discussions were held under Chatham House rules. High-throughput screening of new vaccine antigens and candidates was seen as a driving force for vaccine discovery. Multi-stakeholder, small-scale manufacturing facilities capable of rapid production of clinical grade vaccines are currently too few and need to be expanded. In both the human and veterinary areas, there is a need for tiered regulatory standards, differentially tailored for experimental and commercial vaccines, to allow accelerated vaccine efficacy testing. Improved cross-fertilization of knowledge between industry and academia, and between human and veterinary vaccine developers, could lead to more rapid application of promising approaches and technologies to new product development. Identification of best-practices and development of checklists for product development plans and implementation programmes were seen as low-cost opportunities to shorten the timeline for vaccine progression from the laboratory bench to the people who need it. PMID:21893549

Analysis of IAEA Environmental Samples for Plutonium and Uranium by ICP/MS in Support Of International Safeguards

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farmer, Orville T.; Olsen, Khris B.; Thomas, May-Lin P.

2008-05-01

A method for the separation and determination of total and isotopic uranium and plutonium by ICP-MS was developed for IAEA samples on cellulose-based media. Preparation of the IAEA samples involved a series of redox chemistries and separations using TRU® resin (Eichrom). The sample introduction system, an APEX nebulizer (Elemental Scientific, Inc), provided enhanced nebulization for a several-fold increase in sensitivity and reduction in background. Application of mass bias (ALPHA) correction factors greatly improved the precision of the data. By combining the enhancements of chemical separation, instrumentation and data processing, detection levels for uranium and plutonium approached high attogram levels.

Migration to Earth Observation Satellite Product Dissemination System at JAXA

NASA Astrophysics Data System (ADS)

Ikehata, Y.; Matsunaga, M.

2017-12-01

JAXA released "G-Portal" as a portal web site for search and deliver data of Earth observation satellites in February 2013. G-Portal handles ten satellites data; GPM, TRMM, Aqua, ADEOS-II, ALOS (search only), ALOS-2 (search only), MOS-1, MOS-1b, ERS-1 and JERS-1 and archives 5.17 million products and 14 million catalogues in total. Users can search those products/catalogues in GUI web search and catalogue interface(CSW/Opensearch). In this fiscal year, we will replace this to "Next G-Portal" and has been doing integration, test and migrations. New G-Portal will treat data of satellites planned to be launched in the future in addition to those handled by G - Portal. At system architecture perspective, G-Portal adopted "cluster system" for its redundancy, so we must replace the servers into those with higher specifications when we improve its performance ("scale up approach"). This requests a lot of cost in every improvement. To avoid this, Next G-Portal adopts "scale out" system: load balancing interfaces, distributed file system, distributed data bases. (We reported in AGU fall meeting 2015(IN23D-1748).) At customer usability perspective, G-Portal provides complicated interface: "step by step" web design, randomly generated URLs, sftp (needs anomaly tcp port). Customers complained about the interfaces and the support team had been tired from answering them. To solve this problem, Next G-Portal adopts simple interfaces: "1 page" web design, RESTful URL, and Normal FTP. (We reported in AGU fall meeting 2016(IN23B-1778).) Furthermore, Next G-Portal must merge GCOM-W data dissemination system to be terminated in the next March as well as the current G-Portal. This might arrise some difficulties, since the current G-Portal and GCOM-W data dissemination systems are quite different from Next G-Portal. The presentation reports the knowledge obtained from the process of merging those systems.

Satellite image collection optimization

NASA Astrophysics Data System (ADS)

Martin, William

2002-09-01

Imaging satellite systems represent a high capital cost. Optimizing the collection of images is critical for both satisfying customer orders and building a sustainable satellite operations business. We describe the functions of an operational, multivariable, time dynamic optimization system that maximizes the daily collection of satellite images. A graphical user interface allows the operator to quickly see the results of what if adjustments to an image collection plan. Used for both long range planning and daily collection scheduling of Space Imaging's IKONOS satellite, the satellite control and tasking (SCT) software allows collection commands to be altered up to 10 min before upload to the satellite.

Small satellite product assurance

NASA Astrophysics Data System (ADS)

Demontlivault, J.; Cadelec, Jacques

1993-01-01

In order to increase the interest in small satellites, their cost must be reduced; reducing product assurance costs induced by quality requirements is a major objective. For a logical approach, small satellites are classified in three main categories: satellites for experimental operations with a short lifetime, operational satellites manufactured in small mass with long lifetime requirements, operational satellites (long lifetime required), of which only a few models are produced. The various requirements as regards the product assurance are examined for each satellite category: general requirements for space approach, reliability, electronic components, materials and processes, quality assurance, documentation, tests, and management. Ideal product assurance system integrates quality teams and engineering teams.

Satellite Antenna Systems

NASA Technical Reports Server (NTRS)

1997-01-01

Through the Technology Affiliates Program at the Jet Propulsion Laboratory, the ACTS antenna system was transferred from experimental testing status to commercial development with KVH Industries, Inc. The ACTS design enables mobile satellite antennas to remain pointed at the satellite, regardless of the motion or vibration on which it is mounted. KVH's first product based on the ACTS design is a land-mobile satellite antenna system that will enable direct broadcast satellite television aboard moving trucks, recreational vehicles, trains, and buses. Future products could include use in broadcasting, emergency medical and military vehicles.

Reference dosimeter system of the iaea

NASA Astrophysics Data System (ADS)

Mehta, Kishor; Girzikowsky, Reinhard

1995-09-01

Quality assurance programmes must be in operation at radiation processing facilities to satisfy national and international Standards. Since dosimetry has a vital function in these QA programmes, it is imperative that the dosimetry systems in use at these facilities are well calibrated with a traceability to a Primary Standard Dosimetry Laboratory. As a service to the Member States, the International Atomic Energy Agency operates the International Dose Assurance Service (IDAS) to assist in this process. The transfer standard dosimetry system that is used for this service is based on ESR spectrometry. The paper describes the activities undertaken at the IAEA Dosimetry Laboratory to establish the QA programme for its reference dosimetry system. There are four key elements of such a programme: quality assurance manual; calibration that is traceable to a Primary Standard Dosimetry Laboratory; a clear and detailed statement of uncertainty in the dose measurement; and, periodic quality audit.

Determination of the number of navigation satellites within satellite acquisition range

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurenkov, Vladimir I., E-mail: kvi.48@mail.ru, E-mail: ask@ssau.ru; Kucherov, Alexander S., E-mail: kvi.48@mail.ru, E-mail: ask@ssau.ru; Gordeev, Alexey I., E-mail: exactoone@yahoo.com

2014-12-10

The problem of determination of the number of navigation satellites within acquisition range with regard to antenna systems configuration and stochastic land remote sensing satellite maneuvers is the subject considered in the paper. Distribution function and density function of the number of navigation satellites within acquisition range are obtained.

Proceedings of the 2009 annual meeting of the Fetal Alcohol Spectrum Disorders Study Group

PubMed Central

Zhou, Feng C.; Kane, Cynthia J.M.; Smith, Susan M.

2013-01-01

The annual meeting of the Fetal Alcohol Spectrum Disorders Study Group (FASDSG) was held on June 20, 2009 in San Diego, CA, as a satellite of the Research Society on Alcoholism Meeting. The FASDSG membership includes clinical, basic, and social scientists who meet to discuss recent advances and issues in Fetal Alcohol Spectrum Disorders research. The main theme of the meeting was “Epigenetics and Development.” Two keynote speakers, Dr. Randy Jirtle and Dr. Michael Skinner, addressed the role of epigenetics and environmental inputs, including alcohol, during critical stages of development and their potential critical and long-lasting effects. Members of the FASDSG provided new findings through brief “FASt” data reports, and national agency representatives provided updates on activities and funding priorities. Scientific presentations were made by recipients of the Student Research Merit Award and Rosett Award. PMID:21621368

Joint Polar Satellite System (JPSS) Common Ground System (CGS) Technical Performance Measures of the Block 2 Architecture

NASA Astrophysics Data System (ADS)

Grant, K. D.; Panas, M.

2016-12-01

NOAA and NASA are jointly acquiring the next-generation civilian weather satellite system: the Joint Polar Satellite System (JPSS). JPSS replaced the afternoon orbit component and ground processing of NOAA's old POES system. JPSS satellites carry sensors that collect meteorological, oceanographic, climatological, and solar-geophysical observations of the earth, atmosphere, and space. The ground processing system for JPSS is known as the JPSS Common Ground System (JPSS CGS). Developed and maintained by Raytheon Intelligence, Information and Services (IIS), the CGS is a globally distributed, multi-mission system serving NOAA, NASA and their national and international partners. The CGS has demonstrated its scalability and flexibility to incorporate multiple missions efficiently and with minimal cost, schedule and risk, while strengthening global partnerships in weather and environmental monitoring. The CGS architecture has been upgraded to Block 2.0 to satisfy several key objectives, including: "operationalizing" the first satellite, Suomi NPP, which originally was a risk reduction mission; leveraging lessons learned in multi-mission support, taking advantage of newer, more reliable and efficient technologies and satisfying constraints due of the continually evolving budgetary environment. To ensure the CGS meets these needs, we have developed 48 Technical Performance Measures (TPMs) across 9 categories: Data Availability, Data Latency, Operational Availability, Margin, Scalability, Situational Awareness, Transition (between environments and sites), WAN Efficiency, and Data Recovery Processing. This paper will provide an overview of the CGS Block 2.0 architecture, with particular focus on the 9 TPM categories listed above. We will describe how we ensure the deployed architecture meets these TPMs to satisfy our multi-mission objectives with the deployment of Block 2.0.

GPS-Based Precision Orbit Determination for a New Era of Altimeter Satellites: Jason-1 and ICESat

NASA Technical Reports Server (NTRS)

Luthcke, Scott B.; Rowlands, David D.; Lemoine, Frank G.; Zelensky, Nikita P.; Williams, Teresa A.

2003-01-01

Accurate positioning of the satellite center of mass is necessary in meeting an altimeter mission's science goals. The fundamental science observation is an altimetric derived topographic height. Errors in positioning the satellite's center of mass directly impact this fundamental observation. Therefore, orbit error is a critical Component in the error budget of altimeter satellites. With the launch of the Jason-1 radar altimeter (Dec. 2001) and the ICESat laser altimeter (Jan. 2003) a new era of satellite altimetry has begun. Both missions pose several challenges for precision orbit determination (POD). The Jason-1 radial orbit accuracy goal is 1 cm, while ICESat (600 km) at a much lower altitude than Jason-1 (1300 km), has a radial orbit accuracy requirement of less than 5 cm. Fortunately, Jason-1 and ICESat POD can rely on near continuous tracking data from the dual frequency codeless BlackJack GPS receiver and Satellite Laser Ranging. Analysis of current GPS-based solution performance indicates the l-cm radial orbit accuracy goal is being met for Jason-1, while radial orbit accuracy for ICESat is well below the 54x1 mission requirement. A brief overview of the GPS precision orbit determination methodology and results for both Jason-1 and ICESat are presented.

Region Spherical Harmonic Magnetic Modeling from Near-Surface and Satellite-Altitude Anomlaies

NASA Technical Reports Server (NTRS)

Kim, Hyung Rae; von Frese, Ralph R. B.; Taylor, Patrick T.

2013-01-01

The compiled near-surface data and satellite crustal magnetic measured data are modeled with a regionally concentrated spherical harmonic presentation technique over Australia and Antarctica. Global crustal magnetic anomaly studies have used a spherical harmonic analysis to represent the Earth's magnetic crustal field. This global approach, however is best applied where the data are uniformly distributed over the entire Earth. Satellite observations generally meet this requirement, but unequally distributed data cannot be easily adapted in global modeling. Even for the satellite observations, due to the errors spread over the globe, data smoothing is inevitable in the global spherical harmonic presentations. In addition, global high-resolution modeling requires a great number of global spherical harmonic coefficients for the regional presentation of crustal magnetic anomalies, whereas a lesser number of localized spherical coefficients will satisfy. We compared methods in both global and regional approaches and for a case where the errors were propagated outside the region of interest. For observations from the upcoming Swarm constellation, the regional modeling will allow the production a lesser number of spherical coefficients that are relevant to the region of interest

IAEA Coordinated Research Project on HTGR Reactor Physics, Thermal-hydraulics and Depletion Uncertainty Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Strydom, Gerhard; Bostelmann, F.

The continued development of High Temperature Gas Cooled Reactors (HTGRs) requires verification of HTGR design and safety features with reliable high fidelity physics models and robust, efficient, and accurate codes. The predictive capability of coupled neutronics/thermal-hydraulics and depletion simulations for reactor design and safety analysis can be assessed with sensitivity analysis (SA) and uncertainty analysis (UA) methods. Uncertainty originates from errors in physical data, manufacturing uncertainties, modelling and computational algorithms. (The interested reader is referred to the large body of published SA and UA literature for a more complete overview of the various types of uncertainties, methodologies and results obtained).more » SA is helpful for ranking the various sources of uncertainty and error in the results of core analyses. SA and UA are required to address cost, safety, and licensing needs and should be applied to all aspects of reactor multi-physics simulation. SA and UA can guide experimental, modelling, and algorithm research and development. Current SA and UA rely either on derivative-based methods such as stochastic sampling methods or on generalized perturbation theory to obtain sensitivity coefficients. Neither approach addresses all needs. In order to benefit from recent advances in modelling and simulation and the availability of new covariance data (nuclear data uncertainties) extensive sensitivity and uncertainty studies are needed for quantification of the impact of different sources of uncertainties on the design and safety parameters of HTGRs. Only a parallel effort in advanced simulation and in nuclear data improvement will be able to provide designers with more robust and well validated calculation tools to meet design target accuracies. In February 2009, the Technical Working Group on Gas-Cooled Reactors (TWG-GCR) of the International Atomic Energy Agency (IAEA) recommended that the proposed Coordinated Research Program

Secretary of Energy Steven Chu speaks to the 2009 IAEA General Conference delegation

ScienceCinema

Secretary Chu

2017-12-09

On Sept. 14, 2009, U.S. Secretary of Energy Steven Chu addressed the 2009 IAEA General Conference delegation. Chu is the first Cabinet official to discuss President Obama's nuclear security and nonproliferation agenda outside the United States since the President delivered his landmark speech in Prague in April 2009.

TDF-1, The French Broadcasting Satellite (TDF-1, Satellite Francais de Radiodiffusion),

DTIC Science & Technology

1982-04-22

defines the general directions of the program and gives the necessary directives to a joint project directorate in Munich, Germany ( French projects ...AD-A117 961 NAVAL ZNTELIGENC SUPPORT CENTER WASHINGTON DC TRAN-(ITC F/0 17/2 TOF-Il, THE FRENCH BROADCASTING SATELLITE (TDP-I. SATELLITE PRAN-ETC(U...8201/80A UNCLASSIFIED TITLE: TDF-1, The French Broadcasting Satellite TDF 1, satellite francais de radiodiffusion AUTHOR(S) AND/OR EDITOR(S): C

Building a COTS archive for satellite data

NASA Technical Reports Server (NTRS)

Singer, Ken; Terril, Dave; Kelly, Jack; Nichols, Cathy

1994-01-01

The goal of the NOAA/NESDIS Active Archive was to provide a method of access to an online archive of satellite data. The archive had to manage and store the data, let users interrogate the archive, and allow users to retrieve data from the archive. Practical issues of the system design such as implementation time, cost and operational support were examined in addition to the technical issues. There was a fixed window of opportunity to create an operational system, along with budget and staffing constraints. Therefore, the technical solution had to be designed and implemented subject to constraint imposed by the practical issues. The NOAA/NESDIS Active Archive came online in July of 1994, meeting all of its original objectives.

Higher resolution satellite remote sensing and the impact on image mapping

USGS Publications Warehouse

Watkins, Allen H.; Thormodsgard, June M.

1987-01-01

Recent advances in spatial, spectral, and temporal resolution of civil land remote sensing satellite data are presenting new opportunities for image mapping applications. The U.S. Geological Survey's experimental satellite image mapping program is evolving toward larger scale image map products with increased information content as a result of improved image processing techniques and increased resolution. Thematic mapper data are being used to produce experimental image maps at 1:100,000 scale that meet established U.S. and European map accuracy standards. Availability of high quality, cloud-free, 30-meter ground resolution multispectral data from the Landsat thematic mapper sensor, along with 10-meter ground resolution panchromatic and 20-meter ground resolution multispectral data from the recently launched French SPOT satellite, present new cartographic and image processing challenges.The need to fully exploit these higher resolution data increases the complexity of processing the images into large-scale image maps. The removal of radiometric artifacts and noise prior to geometric correction can be accomplished by using a variety of image processing filters and transforms. Sensor modeling and image restoration techniques allow maximum retention of spatial and radiometric information. An optimum combination of spectral information and spatial resolution can be obtained by merging different sensor types. These processing techniques are discussed and examples are presented.

Large-Scale Experimental Planetary Science Meets Planetary Defense: Deorbiting an Asteroidal Satellite

NASA Technical Reports Server (NTRS)

Cintala, M. J.; Durda, D. D.; Housen, K. R.

2005-01-01

Other than remote-sensing and spacecraft-derived data, the only information that exists regarding the physical and chemical properties of asteroids is that inferred through calculations, numerical simulations, extrapolation of experiments, and meteorite studies. Our understanding of the dynamics of accretion of planetesimals, collisional disruption of asteroids, and the macroscopic, shock-induced modification of the surfaces of such small objects is also, for the most part, founded on similar inferences. While considerable strides have been made in improving the state of asteroid science, too many unknowns remain to assert that we understand the parameters necessary for the more practical problem of deflecting an asteroid or asteroid pair on an Earth-intersecting trajectory. Many of these deficiencies could be reduced or eliminated by intentionally deorbiting an asteroidal satellite and monitoring the resulting collision between it and the primary asteroid, a capability that is well within the limitations of current technology.

LARES Laser Relativity Satellite

NASA Astrophysics Data System (ADS)

Ciufolini, Ignazio; et al.

2011-05-01

After almost three decades since the first idea of launching a passive satellite to measure gravitomagnetism, launch of LARES satellite is approaching. The new developed VEGA launcher will carry LARES in a nominally circular orbit at 1450 km altitude. This satellite, along with the two LAGEOS satellites, will allow to improve a previous measurement of the Lense-Thirring effect by a factor of 10. This important achievement will be a result of the idea of combining orbital parameters of a constellation of laser ranging satellites along with a specific design of LARES satellite. Other key points of the experiment are: the ever improving knowledge of the gravitational field of Earth, in particular the lower degree even zonal harmonics with GRACE satellites, and an accurate estimate of all the classical perturbations such as atmospheric drag and solar radiation pressure. In the paper both the scientific aspects as well as the design consideration will be described

Exploring the boundaries of quantum mechanics: advances in satellite quantum communications.

PubMed

Agnesi, Costantino; Vedovato, Francesco; Schiavon, Matteo; Dequal, Daniele; Calderaro, Luca; Tomasin, Marco; Marangon, Davide G; Stanco, Andrea; Luceri, Vincenza; Bianco, Giuseppe; Vallone, Giuseppe; Villoresi, Paolo

2018-07-13

Recent interest in quantum communications has stimulated great technological progress in satellite quantum technologies. These advances have rendered the aforesaid technologies mature enough to support the realization of experiments that test the foundations of quantum theory at unprecedented scales and in the unexplored space environment. Such experiments, in fact, could explore the boundaries of quantum theory and may provide new insights to investigate phenomena where gravity affects quantum objects. Here, we review recent results in satellite quantum communications and discuss possible phenomena that could be observable with current technologies. Furthermore, stressing the fact that space represents an incredible resource to realize new experiments aimed at highlighting some physical effects, we challenge the community to propose new experiments that unveil the interplay between quantum mechanics and gravity that could be realizable in the near future.This article is part of a discussion meeting issue 'Foundations of quantum mechanics and their impact on contemporary society'. © 2018 The Author(s).

Status of NASA Satellite, Field Observations, and Numerical Modeling Addressing the Impact of Urbanization on Short and Long Term Precipitation Variability

NASA Technical Reports Server (NTRS)

Shepherd, J. Marshall; Manyin, Michael; Burian, Steve; Garza, Carlos

2003-01-01

There is renewed interest in the impacts of urbanization on global change as witnessed by special sessions at the Fall AGU and Annual AMS meeting. A comprehensive satellite, modeling, and field campaign program is underway to assess the impact of urbanization on precipitation.

Space Solar Power Satellite Systems, Modern Small Satellites, and Space Rectenna

NASA Astrophysics Data System (ADS)

Bergsrud, Corey Alexis Marvin

Space solar power satellite (SSPS) systems is the concept of placing large satellite into geostationary Earth orbit (GEO) to harvest and convert massive amounts of solar energy into microwave energy, and to transmit the microwaves to a rectifying antenna (rectenna) array on Earth. The rectenna array captures and converts the microwave power into usable power that is injected into the terrestrial electric grid for use. This work approached the microwave power beam as an additional source of power (with solar) for lower orbiting satellites. Assuming the concept of retrodirectivity, a GEO-SSPS antenna array system tracks and delivers microwave power to lower orbiting satellites. The lower orbiting satellites are equipped with a stacked photovoltaic (PV)/rectenna array hybrid power generation unit (HPGU) in order to harvest solar and/or microwave energy for on-board use during orbit. The area, and mass of the PV array part of the HPGU was reduced at about 32% beginning-of-life power in order to achieve the spacecraft power requirements. The HPGU proved to offer a mass decrease in the PGU, and an increase in mission life due to longer living component life of the rectenna array. Moreover, greater mission flexibility is achieved through a track and power delivery concept. To validate the potential advantages offered by a HPGU, a mission concept was presented that utilizes modern small satellites as technology demonstrators. During launch, a smaller power receiving "daughter" satellite sits inside a larger power transmitting "mother" satellite. Once separated from the launch vehicle the daughter satellite is ejected away from the mother satellite, and each satellite deploys its respective power transmitting or power receiving hardware's for experimentation. The concept of close proximity mission operations between the satellites is considered. To validate the technology of the space rectenna array part of the HPGU, six milestones were completed in the design. The first

Three Generations of Tracking and Data Relay Satellite (TDRS) Spacecraft

NASA Technical Reports Server (NTRS)

Zaleski, Ron

2016-01-01

The current Tracking and Data Relay Satellite configuration consists of nine in-orbit satellites (four first generation, three second generation and two third generation satellites) globally distributed in geosynchronous orbit to provide near continuous data relay service to missions like Hubble Space Telescope and the International Space Station. The 1st generation spacecraft were designed by TRW/Northrop Grumman with their launches of the five spacecraft ranging from 1983 through 1995. The 2nd and 3rd generation spacecraft were designed by Boeing with their launches ranging 2000 - 2002 and 2013 - 2017 respectively. TDRS-3 is now 27 years on orbit, continues to be a capable asset for the TDRS constellation. Lack of need for inclination control combined with large fuel reserves and redundancy on critical elements provides spacecraft that operate well past design life, all of which contributes to expanded TDRS constellation support capabilities. All spacecraft generations have issues. Significant issues will be summarized with the focus on the Boeing related problems. Degradations and failures are continually assessed and provide the foundation for yearly updates to spacecraft reliability models, constellation service projections and deorbit plans (in order to meet NASAs mandate of limiting orbital debris). Even when accounting for degradations and failures, the life expectancy for the Boeing delivered 2nd generation TDRS-8, 9 10 TDRS are anticipated to be 25+ years.

SatelliteDL: a Toolkit for Analysis of Heterogeneous Satellite Datasets

NASA Astrophysics Data System (ADS)

Galloy, M. D.; Fillmore, D.

2014-12-01

SatelliteDL is an IDL toolkit for the analysis of satellite Earth observations from a diverse set of platforms and sensors. The core function of the toolkit is the spatial and temporal alignment of satellite swath and geostationary data. The design features an abstraction layer that allows for easy inclusion of new datasets in a modular way. Our overarching objective is to create utilities that automate the mundane aspects of satellite data analysis, are extensible and maintainable, and do not place limitations on the analysis itself. IDL has a powerful suite of statistical and visualization tools that can be used in conjunction with SatelliteDL. Toward this end we have constructed SatelliteDL to include (1) HTML and LaTeX API document generation,(2) a unit test framework,(3) automatic message and error logs,(4) HTML and LaTeX plot and table generation, and(5) several real world examples with bundled datasets available for download. For ease of use, datasets, variables and optional workflows may be specified in a flexible format configuration file. Configuration statements may specify, for example, a region and date range, and the creation of images, plots and statistical summary tables for a long list of variables. SatelliteDL enforces data provenance; all data should be traceable and reproducible. The output NetCDF file metadata holds a complete history of the original datasets and their transformations, and a method exists to reconstruct a configuration file from this information. Release 0.1.0 distributes with ingest methods for GOES, MODIS, VIIRS and CERES radiance data (L1) as well as select 2D atmosphere products (L2) such as aerosol and cloud (MODIS and VIIRS) and radiant flux (CERES). Future releases will provide ingest methods for ocean and land surface products, gridded and time averaged datasets (L3 Daily, Monthly and Yearly), and support for 3D products such as temperature and water vapor profiles. Emphasis will be on NPP Sensor, Environmental and

MEMS-Based Satellite Micropropulsion Via Catalyzed Hydrogen Peroxide Decomposition

NASA Technical Reports Server (NTRS)

Hitt, Darren L.; Zakrzwski, Charles M.; Thomas, Michael A.; Bauer, Frank H. (Technical Monitor)

2001-01-01

Micro-electromechanical systems (MEMS) techniques offer great potential in satisfying the mission requirements for the next generation of "micro-scale" satellites being designed by NASA and Department of Defense agencies. More commonly referred to as "nanosats", these miniature satellites feature masses in the range of 10-100 kg and therefore have unique propulsion requirements. The propulsion systems must be capable of providing extremely low levels of thrust and impulse while also satisfying stringent demands on size, mass, power consumption and cost. We begin with an overview of micropropulsion requirements and some current MEMS-based strategies being developed to meet these needs. The remainder of the article focuses the progress being made at NASA Goddard Space Flight Center towards the development of a prototype monopropellant MEMS thruster which uses the catalyzed chemical decomposition of high concentration hydrogen peroxide as a propulsion mechanism. The products of decomposition are delivered to a micro-scale converging/diverging supersonic nozzle which produces the thrust vector; the targeted thrust level approximately 500 N with a specific impulse of 140-180 seconds. Macro-scale hydrogen peroxide thrusters have been used for satellite propulsion for decades; however, the implementation of traditional thruster designs on a MEMS scale has uncovered new challenges in fabrication, materials compatibility, and combustion and hydrodynamic modeling. A summary of the achievements of the project to date is given, as is a discussion of remaining challenges and future prospects.

Autonomous Satellite Operations Via Secure Virtual Mission Operations Center

NASA Technical Reports Server (NTRS)

Miller, Eric; Paulsen, Phillip E.; Pasciuto, Michael

2011-01-01

The science community is interested in improving their ability to respond to rapidly evolving, transient phenomena via autonomous rapid reconfiguration, which derives from the ability to assemble separate but collaborating sensors and data forecasting systems to meet a broad range of research and application needs. Current satellite systems typically require human intervention to respond to triggers from dissimilar sensor systems. Additionally, satellite ground services often need to be coordinated days or weeks in advance. Finally, the boundaries between the various sensor systems that make up such a Sensor Web are defined by such things as link delay and connectivity, data and error rate asymmetry, data reliability, quality of service provisions, and trust, complicating autonomous operations. Over the past ten years, researchers from the NASA Glenn Research Center (GRC), General Dynamics, Surrey Satellite Technology Limited (SSTL), Cisco, Universal Space Networks (USN), the U.S. Geological Survey (USGS), the Naval Research Laboratory, the DoD Operationally Responsive Space (ORS) Office, and others have worked collaboratively to develop a virtual mission operations capability. Called VMOC (Virtual Mission Operations Center), this new capability allows cross-system queuing of dissimilar mission unique systems through the use of a common security scheme and published application programming interfaces (APIs). Collaborative VMOC demonstrations over the last several years have supported the standardization of spacecraft to ground interfaces needed to reduce costs, maximize space effects to the user, and allow the generation of new tactics, techniques and procedures that lead to responsive space employment.

Interim Service ISDN Satellite (ISIS) network model for advanced satellite designs and experiments

NASA Technical Reports Server (NTRS)

Pepin, Gerard R.; Hager, E. Paul

1991-01-01

The Interim Service Integrated Services Digital Network (ISDN) Satellite (ISIS) Network Model for Advanced Satellite Designs and Experiments describes a model suitable for discrete event simulations. A top-down model design uses the Advanced Communications Technology Satellite (ACTS) as its basis. The ISDN modeling abstractions are added to permit the determination and performance for the NASA Satellite Communications Research (SCAR) Program.

Quality of radiotherapy services in post-Soviet countries: An IAEA survey.

PubMed

Rosenblatt, Eduardo; Fidarova, Elena; Ghosh, Sunita; Zubizarreta, Eduardo; Unterkirhere, Olga; Semikoz, Natalia; Sinaika, Valery; Kim, Viktor; Karamyan, Nerses; Isayev, Isa; Akbarov, Kamal; Lomidze, Darejan; Bondareva, Oksana; Tuzlucov, Piotr; Zardodkhonova, Manzura; Tkachev, Sergey; Kislyakova, Marina; Alimov, Jamshid; Pidlubna, Tetiana; Barton, Michael; Mackillop, William

2018-04-25

The quality of radiotherapy services in post-Soviet countries has not yet been studied following a formal methodology. The IAEA conducted a survey using two sets of validated radiation oncology quality indicators (ROIs). Eleven post-Soviet countries were assessed. A coordinator was designated for each country and acted as the liaison between the country and the IAEA. The methodology was a one-time cross-sectional survey using a 58-question tool in Russian. The questionnaire was based on two validated sets of ROIs: for radiotherapy centres, the indicators proposed by Cionini et al., and for data at the country level, the Australasian ROIs. The overall response ratio was 66.3%, but for the Russian Federation, it was 24%. Data were updated on radiotherapy infrastructure and equipment. 256 radiotherapy centres are operating 275 linear accelerators and 337 Cobalt-60 units. 61% of teletherapy machines are older than ten years. Analysis of ROIs revealed significant differences between these countries and radiotherapy practices in the West. Naming, task profile and education programmes of radiotherapy professionals are different than in the West. Most countries need modernization of their radiotherapy infrastructure coupled with adequate staffing numbers and updated education programmes focusing on evidence-based medicine, quality, and safety. Copyright © 2018 Elsevier B.V. All rights reserved.

Fundamentals of satellite navigation

NASA Astrophysics Data System (ADS)

Stiller, A. H.

The basic operating principles and capabilities of conventional and satellite-based navigation systems for air, sea, and land vehicles are reviewed and illustrated with diagrams. Consideration is given to autonomous onboard systems; systems based on visible or radio beacons; the Transit, Cicada, Navstar-GPS, and Glonass satellite systems; the physical laws and parameters of satellite motion; the definition of time in satellite systems; and the content of the demodulated GPS data signal. The GPS and Glonass data format frames are presented graphically, and tables listing the GPS and Glonass satellites, their technical characteristics, and the (past or scheduled) launch dates are provided.

The dynamic phenomena of a tethered satellite: NASA's first Tethered Satellite Mission, TSS-1

NASA Technical Reports Server (NTRS)

Ryan, R. S.; Mowery, D. K.; Tomlin, D. D.

1993-01-01

The tethered satellite system (TSS) was envisioned as a means of extending a satellite from its base (space shuttle, space station, space platform) into a lower or higher altitude in order to more efficiently acquire data and perform science experiments. This is accomplished by attaching the satellite to a tether, deploying it, then reeling it in. When its mission is completed, the satellite can be returned to its base for reuse. If the tether contains a conductor, it can also be used as a means to generate and flow current to and from the satellite to the base. When current is flowed, the tether interacts with the Earth's magnetic field, deflecting the tether. When the current flows in one direction, the system becomes a propulsive system that can be used to boost the orbiting system. In the other direction, it is a power generating system. Pulsing the current sets up a dynamic oscillation in the tether, which can upset the satellite attitude and preclude docking. A basic problem occurs around 400-m tether length, during satellite retrieval when the satellite's pendulous (rotational) mode gets in resonance with the first lateral tether string mode. The problem's magnitude is determined by the amount of skiprope present coming into this resonance condition. This paper deals with the tethered satellite, its dynamic phenomena, and how the resulting problems were solved for the first tethered satellite mission (TSS-1). Proposals for improvements for future tethered satellite missions are included. Results from the first tethered satellite flight are summarized.

Orbital Perturbations of the Galilean Satellites during Planetary Encounters

NASA Astrophysics Data System (ADS)

Deienno, Rogerio; Nesvorný, David; Vokrouhlický, David; Yokoyama, Tadashi

2014-08-01

The Nice model of the dynamical instability and migration of the giant planets can explain many properties of the present solar system, and can be used to constrain its early architecture. In the jumping-Jupiter version of the Nice model, required from the terrestrial planet constraint and dynamical structure of the asteroid belt, Jupiter has encounters with an ice giant. Here, we study the survival of the Galilean satellites in the jumping-Jupiter model. This is an important concern because the ice-giant encounters, if deep enough, could dynamically perturb the orbits of the Galilean satellites and lead to implausible results. We performed numerical integrations where we tracked the effect of planetary encounters on the Galilean moons. We considered three instability cases from Nesvorný & Morbidelli that differed in the number and distribution of encounters. We found that in one case, where the number of close encounters was relatively small, the Galilean satellite orbits were not significantly affected. In the other two, the orbital eccentricities of all moons were excited by encounters, Callisto's semimajor axis changed, and, in a large fraction of trials, the Laplace resonance of the inner three moons was disrupted. The subsequent evolution by tides damps eccentricities and can recapture the moons in the Laplace resonance. A more important constraint is represented by the orbital inclinations of the moons, which can be excited during the encounters and not appreciably damped by tides. We find that one instability case taken from Nesvorný & Morbidelli clearly does not meet this constraint. This shows how the regular satellites of Jupiter can be used to set limits on the properties of encounters in the jumping-Jupiter model, and help us to better understand how the early solar system evolved.

Progress developing the JAXA next generation satellite data repository (G-Portal).

NASA Astrophysics Data System (ADS)

Ikehata, Y.

2016-12-01

JAXA has been operating the "G-Portal" as a repository for search and access data of Earth observation satellite related JAXA since February 2013. The G-Portal handles ten satellites data; GPM, TRMM, Aqua, ADEOS-II, ALOS (search only), ALOS-2 (search only), MOS-1, MOS-1b, ERS-1 and JERS-1. G-Portal plans to import future satellites GCOM-C and EarthCARE. Except for ALOS and ALOS-2, all of these data are open and free. The G-Portal supports web search, catalogue search (CSW and OpenSearch) and direct download by SFTP for data access. However, the G-Portal has some problems about performance and usability. For example, about performance, the G-Portal is based on 10Gbps network and uses scale out architecture. (Conceptual design was reported in AGU fall meeting 2015. (IN23D-1748)) In order to improve those problems, JAXA is developing the next generation repository since February 2016. This paper describes usability problems improvements and challenges towards the next generation system. The improvements and challenges include the following points. Current web interface uses "step by step" design and URL is generated randomly. For that reason, users must see the Web page and click many times to get desired satellite data. So, Web design will be changed completely from "step by step" to "1 page" and URL will be based on REST (REpresentational State Transfer). Regarding direct download, the current method(SFTP) is very hard to use because of anomaly port assign and key-authentication. So, we will support FTP protocol. Additionally, the next G-Portal improve catalogue service. Currently catalogue search is available only to limited users including NASA, ESA and CEOS due to performance and reliability issue, but we will remove this limitation. Furthermore, catalogue search client function will be implemented to take in other agencies satellites catalogue. Users will be able to search satellite data across agencies.

Technology assessment of high pulse energy CO(2) lasers for remote sensing from satellites

NASA Technical Reports Server (NTRS)

Hess, R. V.; Brockman, P.; Schryer, D. R.; Miller, I. M.; Bair, C. H.; Sidney, B. D.; Wood, G. M.; Upchurch, B. T.; Brown, K. G.

1985-01-01

Developments and needs for research to extend the lifetime and optimize the configuration of CO2 laser systems for satellite based on remote sensing of atmospheric wind velocities and trace gases are reviewed. The CO2 laser systems for operational satellite application will require lifetimes which exceed 1 year. Progress in the development of efficient low temperature catalysts and gas mixture modifications for extending the lifetime of high pulse energy closed cycle common and rare isotope CO2 lasers and of sealed CW CO2 lasers is reviewed. Several CO2 laser configurations are under development to meet the requirements including: unstable resonators, master oscillator power amplifiers and telescopic stable resonators, using UV or E-beam preionization. Progress in the systems is reviewed and tradeoffs in the system parameters are discussed.

Linked Autonomous Interplanetary Satellite Orbit Navigation

NASA Technical Reports Server (NTRS)

Parker, Jeffrey S.; Anderson, Rodney L.; Born, George H.; Leonard, Jason M.; McGranaghan, Ryan M.; Fujimoto, Kohei

2013-01-01

A navigation technology known as LiAISON (Linked Autonomous Interplanetary Satellite Orbit Navigation) has been known to produce very impressive navigation results for scenarios involving two or more cooperative satellites near the Moon, such that at least one satellite must be in an orbit significantly perturbed by the Earth, such as a lunar halo orbit. The two (or more) satellites track each other using satellite-to-satellite range and/or range-rate measurements. These relative measurements yield absolute orbit navigation when one of the satellites is in a lunar halo orbit, or the like. The geometry between a lunar halo orbiter and a GEO satellite continuously changes, which dramatically improves the information content of a satellite-to-satellite tracking signal. The geometrical variations include significant out-of-plane shifts, as well as inplane shifts. Further, the GEO satellite is almost continuously in view of a lunar halo orbiter. High-fidelity simulations demonstrate that LiAISON technology improves the navigation of GEO orbiters by an order of magnitude, relative to standard ground tracking. If a GEO satellite is navigated using LiAISON- only tracking measurements, its position is typically known to better than 10 meters. If LiAISON measurements are combined with simple radiometric ground observations, then the satellite s position is typically known to better than 3 meters, which is substantially better than the current state of GEO navigation. There are two features of LiAISON that are novel and advantageous compared with conventional satellite navigation. First, ordinary satellite-to-satellite tracking data only provides relative navigation of each satellite. The novelty is the placement of one navigation satellite in an orbit that is significantly perturbed by both the Earth and the Moon. A navigation satellite can track other satellites elsewhere in the Earth-Moon system and acquire knowledge about both satellites absolute positions and velocities

Healthy satellites provide quality service

NASA Astrophysics Data System (ADS)

Margittai, Paul

The procedures used by Telesat Canada to ensure the performance of Anik satellites is described. At the Satellite Telemetry, Tracking and Command station, each Anik satellite has its own dedicated antenna. Telemetered information from the satellites is received, processed and forwarded to the Satellite Control Center. There the satellite controllers issue all commands to the satellites, and continually monitor the telemetered data. These data, describing the state of health of the satellites, are then analyzed by engineering specialists. The satellites are held in their precise orbital positions by means of specially developed software. The Anik C and D satellites employ travelling wave tube amplifiers (TWTAs) in the transpounder channels. The TWTA saturated flux density (SFD) and equivalent isotropic radiated power (EIRP) are regularly measured and their trends scrutinized. This ensures that customers receive the radio frequency power needed for high-quality service. The satellite electrical power is supplied by the solar cell array and batteries. Power system performance is evaluated regularly to ensure that power is available to operate the required number of TWTAs. In addition to rain-fades, short service interruptions can be caused by high voltage trip-offs of TWTAs, and by electrostatic discharge related anomalies. To minimize these interruptions, Telesat ensures that the satellite controllers are fully trained and prepared for any eventuality, and the relevant operational procedures are continually refined. A fully trained staff of satellite controllers keep interruptions caused by high voltage trip-offs of TWTAs and by electrostatic discharge to a minimum.

Tethered satellite control mechanism

NASA Technical Reports Server (NTRS)

Kyrias, G. M.

1983-01-01

The tethered satellite control mechanisms consist of four major subsystems. The reel drive mechanism stores the tether. It is motor driven and includes a level wind to uniformly feed the tether to the reel. The lower boom mechanism serves two primary functions: (1) it measures tether length and velocity as the tether runs through the mechanism, and (2) it reads the tether tension at the reel. It also provides change the direction for the tether from the reel to the upper boom mechanism. The deployment boom positions the upper boom mechanism with satellite out of the cargo bay. The deployment function places the 500-kg satellite 20 m away from the Space Shuttle (producing a small natural gravity gradient force), impacts an initial velocity to the satellite for deployment, and allows for satellite docking at a safe distance from the body of the Space Shuttle. The upper boom mechanism (UBM) services three functions: (1) it provides tether control to the satellite as the satellite swings in and out of plane; (2) it reads tether tension in the low range during the early deployment and final retrieval parts of the mission; and (3) it produces additional tether tension at the reel when tether tension to the satellite is in the low range.

Spacecraft IF switch matrix for wideband service applications in 30/20 GHz communications satellite systems: Proof-of-concept model, executive summary

NASA Technical Reports Server (NTRS)

Ho, P. T.; Coban, E.; Pelose, J.

1983-01-01

The design and development of a unique coupler crossbar 20 x 20 microwave switch matrix are described. The test results of the proof of concept model that meets the requirements for a high speed satellite switched, time division multiple access (SS-TDMA) system are presented.

Artificial satellite break-ups. I - Soviet ocean surveillance satellites

NASA Astrophysics Data System (ADS)

Johnson, N. L.

1983-02-01

An analysis of the breakup patterns of eight Soviet Kosmos series ocean surveillance satellites is presented. It is noted that half of the 4700 objects presently detected in earth orbit are shards from destroyed objects. The locations and heading of each Soviet satellite breakup were tracked by the Naval Space Survelliance System. All events in the eastern hemisphere occurred in the ascending phase, while western hemisphere breakups happened in the descending phase. Gabbard (1971) diagrams of altitude vs. period are plotted as a function of a fragment's orbital period. The diagrams have been incorporated into a NASA computer program to backtrack along the fragments' paths to determine the pattern of the breakup. Although objects have been projected to have separated from some of the satellites before breakup, a discussion of the evidence leads to the conclusion that even though the satellites may have exploded no purpose can yet be discerned for the actions.

Three small deployed satellites

NASA Image and Video Library

2012-10-04

ISS033-E-009282 (4 Oct. 2012) --- Several tiny satellites are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module’s robotic arm on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment. Earth’s horizon and the blackness of space provide the backdrop for the scene.

The American Satellite Company (ASC) satellite deployed from payload bay

NASA Technical Reports Server (NTRS)

1985-01-01

The American Satellite Company (ASC) communications satellite is deployed from the payload bay of the Shuttle Discovery. A portion of the cloudy surface of the earth can be seen to the left of the frame.

Gravimetric geodesy and sea surface topography studies by means of satellite-to-satellite tracking and satellite altimetry

NASA Technical Reports Server (NTRS)

Siry, J. W.

1972-01-01

A satellite-to-satellite tracking experiment is planned between ATS-F and GEOS-C with a range accuracy of 2-meters and a range rate accuracy of 0.035 centimeters per second for a 10-second integration time. This experiment is planned for 1974. It is anticipated that it will improve the spatial resolution of the satellite geoid by half an order of magnitude to about 6 degrees. Longer integration times should also permit a modest increase in the acceleration resolution. Satellite altimeter data will also be obtained by means of GEOS-C. An overall accuracy of 5-meters in altitude is the goal. The altimeter, per se, is expected to have an instrumental precision of about 2 meters, and an additional capability to observe with a precision of about 0.2 meters for limited periods.

Optical satellite communications in Europe

NASA Astrophysics Data System (ADS)

Sodnik, Zoran; Lutz, Hanspeter; Furch, Bernhard; Meyer, Rolf

2010-02-01

This paper describes optical satellite communication activities based on technology developments, which started in Europe more than 30 years ago and led in 2001 to the world-first optical inter-satellite communication link experiment (SILEX). SILEX proved that optical communication technologies can be reliably mastered in space and in 2006 the Japanese Space Agency (JAXA) joined the optical inter-satellite experiment from their own satellite. Since 2008 the German Space Agency (DLR) is operating an inter-satellite link between the NFIRE and TerraSAR-X satellites based on a second generation of laser communication technology, which will be used for the new European Data Relay Satellite (EDRS) system to be deployed in 2013.

Telemetry Data Collection from Oscar Satellite

NASA Technical Reports Server (NTRS)

Haddock, Paul C.; Horan, Stephen

1998-01-01

This paper discusses the design, configuration, and operation of a satellite station built for the Center for Space Telemetering and Telecommunications Laboratory in the Klipsch School of Electrical and Computer Engineering Engineering at New Mexico State University (NMSU). This satellite station consists of a computer-controlled antenna tracking system, 2m/70cm transceiver, satellite tracking software, and a demodulator. The satellite station receives satellite,telemetry, allows for voice communications, and will be used in future classes. Currently this satellite station is receiving telemetry from an amateur radio satellite, UoSAT-OSCAR-11. Amateur radio satellites are referred to as Orbiting Satellites Carrying Amateur Radio (OSCAR) satellites as discussed in the next section.

Towards a tactical nuclear weapons treaty? Is There a Role of IAEA Tools of Safeguards?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saunders, Emily C.; Rowberry, Ariana N.; Fearey, Bryan L.

2012-07-12

In recent years, there is growing interest in formal negotiations on non-strategic or tactical nuclear weapons. With the negotiations of New START, there has been much speculation that a tactical nuclear weapons treaty should be included in the follow on to New START. This paper examines the current policy environment related to tactical weapons and some of the issues surrounding the definition of tactical nuclear weapons. We then map out the steps that would need to be taken in order to begin discussions on a tactical nuclear weapons treaty. These steps will review the potential role of the IAEA inmore » verification of a tactical nuclear weapons treaty. Specifically, does IAEA involvement in various arms control treaties serve as a useful roadmap on how to overcome some of the issues pertaining to a tactical nuclear weapons treaty?« less

IAEA coordinated research project on thermal-hydraulics of Supercritical Water-Cooled Reactors (SCWRs)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamada, K.; Aksan, S. N.

The Supercritical Water-Cooled Reactor (SCWR) is an innovative water-cooled reactor concept, which uses supercritical pressure water as reactor coolant. It has been attracting interest of many researchers in various countries mainly due to its benefits of high thermal efficiency and simple primary systems, resulting in low capital cost. The IAEA started in 2008 a Coordinated Research Project (CRP) on Thermal-Hydraulics of SCWRs as a forum to foster the exchange of technical information and international collaboration in research and development. This paper summarizes the activities and current status of the CRP, as well as major progress achieved to date. At present,more » 15 institutions closely collaborate in several tasks. Some organizations have been conducting thermal-hydraulics experiments and analysing the data, and others have been participating in code-to-test and/or code-to-code benchmark exercises. The expected outputs of the CRP are also discussed. Finally, the paper introduces several IAEA activities relating to or arising from the CRP. (authors)« less

Signal Strength-Based Global Navigation Satellite System Performance Assessment in the Space Service Volume

NASA Technical Reports Server (NTRS)

Welch, Bryan W.

2016-01-01

NASA is participating in the International Committee on Global Navigation Satellite Systems (GNSS) (ICG)'s efforts towards demonstrating the benefits to the space user in the Space Service Volume (SSV) when a multi-GNSS solution space approach is utilized. The ICG Working Group: Enhancement of GNSS Performance, New Services and Capabilities has started a three phase analysis initiative as an outcome of recommendations at the ICG-10 meeting, in preparation for the ICG-11 meeting. The second phase of that increasing complexity and fidelity analysis initiative is based on augmenting the Phase 1 pure geometrical approach with signal strength-based limitations to determine if access is valid. The second phase of analysis has been completed, and the results are documented in this paper.

Trends in mobile satellite communication

NASA Technical Reports Server (NTRS)

Johannsen, Klaus G.; Bowles, Mike W.; Milliken, Samuel; Cherrette, Alan R.; Busche, Gregory C.

1993-01-01

Ever since the U.S. Federal Communication Commission opened the discussion on spectrum usage for personal handheld communication, the community of satellite manufacturers has been searching for an economically viable and technically feasible satellite mobile communication system. Hughes Aircraft Company and others have joined in providing proposals for such systems, ranging from low to medium to geosynchronous orbits. These proposals make it clear that the trend in mobile satellite communication is toward more sophisticated satellites with a large number of spot beams and onboard processing, providing worldwide interconnectivity. Recent Hughes studies indicate that from a cost standpoint the geosynchronous satellite (GEOS) is most economical, followed by the medium earth orbit satellite (MEOS) and then by the low earth orbit satellite (LEOS). From a system performance standpoint, this evaluation may be in reverse order, depending on how the public will react to speech delay and collision. This paper discusses the trends and various mobile satellite constellations in satellite communication under investigation. It considers the effect of orbital altitude and modulation/multiple access on the link and spacecraft design.

JPSS Preparations at the Satellite Proving Ground for Marine, Precipitation, and Satellite Analysis

NASA Technical Reports Server (NTRS)

Folmer, Michael J.; Berndt, E.; Clark, J.; Orrison, A.; Kibler, J.; Sienkiewicz, J.; Nelson, J.; Goldberg, M.; Sjoberg, W.

2016-01-01

The ocean prediction center at the national hurricane center's tropical analysis and forecast Branch, the Weather Prediction center and the Satellite analysis branch of NESDIS make up the Satellite Proving Ground for Marine, Precipitation and Satellite Analysis. These centers had early exposure to JPSS products using the S-NPP Satellite that was launched in 2011. Forecasters continue to evaluate new products in anticipation for the launch of JPSS-1 sometime in 2017.

Three small deployed satellites

NASA Image and Video Library

2012-10-04

ISS033-E-009286 (4 Oct. 2012) --- Several tiny satellites are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module’s robotic arm on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment. A portion of the station’s solar array panels and a blue and white part of Earth provide the backdrop for the scene.

Satellite networks for education.

NASA Technical Reports Server (NTRS)

Singh, J. P.; Morgan, R. P.; Rosenbaum, F. J.

1972-01-01

Consideration of satellite-based educational networking. The characteristics and structure of networks are reviewed, and pressures within the educational establishment that are providing motivation for various types of networks are discussed. A number of studies are cited in which networking needs for educational sectors and services are defined. The current status of educational networking for educational radio and television, instructional television fixed services, inter- and intrastate educational communication networks, computer networks, cable television for education, and continuing and proposed educational experiments using NASA's Applications Technology Satellites is reviewed. Possible satellite-based educational telecommunication services and three alternatives for implementing educational satellite systems are described. Some remarks are made concerning public policy aspects of future educational satellite system development.

Three small deployed satellites

NASA Image and Video Library

2012-10-04

ISS033-E-009285 (4 Oct. 2012) --- Several tiny satellites are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module’s robotic arm on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment. A portion of the station’s solar array panels and a blue and white part of Earth provide the backdrop for the scene.

Plan of Time Management of Satellite Positioning System using Quasi-zenith Satellite

NASA Astrophysics Data System (ADS)

Takahashi, Yasuhiro; Fujieda, Miho; Amagai, Jun; Yokota, Shoichiro; Kimura, Kazuhiro; Ito, Hiroyuki; Hama, Shin'ichi; Morikawa, Takao; Kawano, Isao; Kogure, Satoshi

The Quasi-Zenith satellites System (QZSS) is developed as an integrated satellite service system of communication, broadcasting and positioning for mobile users in specified regions of Japan from high elevation angle. Purposes of the satellite positioning system using Quasi-Zenith satellite (QZS) are to complement and augment the GPS. The national institutes concerned have been developing the positioning system using QZS since 2003 and will carry out experiments and researches in three years after the launch. In this system, National Institute of Information and Communications Technology (NICT) is mainly in charge of timing system for the satellite positioning system using QZS, such as onboard hydrogen maser atomic clock and precise time management system of the QZSS. We started to develop the engineering model of the time management system for the QZSS. The time management system for the QZSS will be used to compare time differences between QZS and earth station as well as to compare between three onboard atomic clocks. This paper introduces time management of satellite positioning system using the QZSS.

A test of the IAEA code of practice for absorbed dose determination in photon and electron beams

NASA Astrophysics Data System (ADS)

Leitner, Arnold; Tiefenboeck, Wilhelm; Witzani, Josef; Strachotinsky, Christian

1990-12-01

The IAEA (International Atomic Energy Agency) code of practice TRS 277 gives recommendations for absorbed dose determination in high energy photon and electron beams based on the use of ionization chambers calibrated in terms of exposure of air kerma. The scope of the work was to test the code for cobalt 60 gamma radiation and for several radiation qualities at four different types of electron accelerators and to compare the ionization chamber dosimetry with ferrous sulphate dosimetry. The results show agreement between the two methods within about one per cent for all the investigated qualities. In addition the response of the TLD capsules of the IAEA/WHO TL dosimetry service was determined.

Jitter reduction of a reaction wheel by management of angular momentum using magnetic torquers in nano- and micro-satellites

NASA Astrophysics Data System (ADS)

Inamori, Takaya; Wang, Jihe; Saisutjarit, Phongsatorn; Nakasuka, Shinichi

2013-07-01

Nowadays, nano- and micro-satellites, which are smaller than conventional large satellites, provide access to space to many satellite developers, and they are attracting interest as an application of space development because development is possible over shorter time period at a lower cost. In most of these nano- and micro-satellite missions, the satellites generally must meet strict attitude requirements for obtaining scientific data under strict constraints of power consumption, space, and weight. In many satellite missions, the jitter of a reaction wheel degrades the performance of the mission detectors and attitude sensors; therefore, jitter should be controlled or isolated to reduce its effect on sensor devices. In conventional standard-sized satellites, tip-tilt mirrors (TTMs) and isolators are used for controlling or isolating the vibrations from reaction wheels; however, it is difficult to use these devices for nano- and micro-satellite missions under the strict power, space, and mass constraints. In this research, the jitter of reaction wheels is reduced by using accurate sensors, small reaction wheels, and slow rotation frequency reaction wheel instead of TTMs and isolators. The objective of a reaction wheel in many satellite missions is the management of the satellite's angular momentum, which increases because of attitude disturbances. If the magnitude of the disturbance is reduced in orbit or on the ground, the magnitude of the angular momentum that the reaction wheels gain from attitude disturbances in orbit becomes smaller; therefore, satellites can stabilize their attitude using only smaller reaction wheels or slow rotation speed, which cause relatively smaller vibration. In nano- and micro-satellite missions, the dominant attitude disturbance is a magnetic torque, which can be cancelled by using magnetic actuators. With the magnetic compensation, the satellite reduces the angular momentum that the reaction wheels gain, and therefore, satellites do

Satellite Technologies in the Classroom.

ERIC Educational Resources Information Center

Portz, Stephen M.

1999-01-01

Focuses on ways of using satellite imagery obtained from the Internet, to enhance classroom learning. Discusses satellite deployment; classroom applications, including infrared imagery, high-resolution photography, and global positioning satellites; and use of satellite data for hands-on activities, including cartography, city and community…

Advanced Communications Technology Satellite (ACTS) Used for Inclined Orbit Operations

NASA Technical Reports Server (NTRS)

Bauer, Robert A.

2000-01-01

to gain greater relevance to the agency s mission from these experiments. One area that is of much interest both to NASA and the commercial world is the investigation of protocol issues related to the interoperability of satellites with terrestrial networks, such as Transmission Control Protocol/Internet Protocol (TCP/IP) and Asynchronous Transfer Mode (ATM) over wideband satellites. Other experiment areas of interest are supporting the U.S. Government and NASA as they begin using commercial space assets to meet their communications needs, evaluating issues related to operating a spot-beam satellite in inclined orbit, and evaluating new Ka-band hardware that requires a satellite link. ACTS is now in its last year of operations. Operations are planned through June 2000, when after 81 months of operations, this very successful spacecraft will be superorbited and made inert.

[Nuclear energy and environment: review of the IAEA environmental projects].

PubMed

Fesenko, S; Fogt, G

2012-01-01

The review of the environmental projects of the International Atomic Energy Agency is presented. Basic IAEA documents intended to protect humans and the Environment are considered and their main features are discussed. Some challenging issues in the area of protection of the Environment and man, including the impact of nuclear facilities on the environment, radioactive waste management, and remediation of the areas affected by radiological accidents, nuclear testing and sites of nuclear facilities are also discussed. The need to maintain the existing knowledge in radioecology and protection of the environment is emphasised.

Renewable Energy SCADA/Training Using NASA's Advanced Technology Communication Satellite

NASA Technical Reports Server (NTRS)

Kalu, A.; Emrich, C.; Ventre, G.; Wilson, W.; Acosta, Roberto (Technical Monitor)

2000-01-01

The lack of electrical energy in the rural communities of developing countries is well known, as is the economic unfeasibility of providing much needed energy to these regions via electric grids. Renewable energy (RE) can provide an economic advantage over conventional forms in meeting some of these energy needs. The use of a Supervisory Control and Data Acquisition (SCADA) arrangement via satellite could enable experts at remote locations to provide technical assistance to local trainees while they acquire a measure of proficiency with a newly installed RE system through hands-on training programs using the same communications link. Upon full mastery of the technologies, indigenous personnel could also employ similar SCADA arrangements to remotely monitor and control their constellation of RE systems. Two separate ACTS technology verification experiments (TVEs) have demonstrated that the portability of the Ultra Small Aperture Terminal (USAT) and the versatility of NASA's Advanced Communications Technology Satellite (ACTS), as well as the advantages of Ka band satellites, can be invaluable in providing energy training via distance education (DE), and for implementing renewable energy system SCADA. What has not been tested is the capabilities of these technologies for a simultaneous implementation of renewable energy DE and SCADA. Such concurrent implementations will be useful for preparing trainees in developing countries for their eventual SCADA operations. The project described in this correspondence is the first effort, to our knowledge, in this specific TVE. The setup for this experiment consists of a one-Watt USAT located at Florida Solar Energy Center (FSEC) connected to two satellite modems tuned to different frequencies to establish two duplex ACTS Ka-band communication channels. A short training program on operation and maintenance of the system will be delivered while simultaneously monitoring and controlling the hybrid using the same satellite

The Himalia Satellite Group: A Case Study on the Dynamical Self-spreading of Families of Irregular Satellites and Asteroids

NASA Astrophysics Data System (ADS)

Li, Daohai; Christou, Apostolos A.

2015-11-01

Many of the outer planets' irregular satellites are grouped into families, thought to originate from collisional fragmentation (Nesvorný et al 2004, AJ). Interestingly, families associated with the largest irregulars are either more dispersed than expected (e.g. J6 Himalia; Nesvorný et al 2003, AJ), or do not exist at all (e.g. S9 Phoebe; Ćuk et al 2003, DDA meeting #34). Christou (2005, Icarus) found that gravitational scattering by Himalia of its own group could explain the large velocity dispersion found by Nesvorný et al (2003, AJ). At the same time, Christou identified a new type of dynamical mechanism that intermittently locks the node of the satellite J10 Lysithea to that of Himalia. The same mechanism, but due to Ceres, was recently found to operate within the Hoffmeister family, dispersing its members and allowing an estimate of its age (Novaković et al 2015, ApJ).Here we revisit the issue of family self-dispersion, aiming to better understand it by studying its effects on the Himalia group. For this we utilise (a) intensive test particle simulations on a larger scale than those by Christou (2005, Icarus) (b) a semi-analytical treatment of the new resonance based on the secular theory of coorbital motion by Namouni (1999, Icarus). This has allowed us to obtain firmer constraints on the rate of dispersion over time and on how the resonance affects the long-term evolution of the orbital elements. A principal result of this work is that particles near the resonance evolve differently than those away from it. During the meeting, we will present a new estimate of the family’s age as well as an analysis of the resonant structure and how it affects Himalia family members. We will also discuss the broader implications for the long-term evolution of orbital concentrations of small bodies in the solar system.Astronomical research at the Armagh Observatory is funded by the Northern Ireland Department of Culture, Arts and Leisure (DCAL).

Improved accuracies for satellite tracking

NASA Technical Reports Server (NTRS)

Kammeyer, P. C.; Fiala, A. D.; Seidelmann, P. K.

1991-01-01

A charge coupled device (CCD) camera on an optical telescope which follows the stars can be used to provide high accuracy comparisons between the line of sight to a satellite, over a large range of satellite altitudes, and lines of sight to nearby stars. The CCD camera can be rotated so the motion of the satellite is down columns of the CCD chip, and charge can be moved from row to row of the chip at a rate which matches the motion of the optical image of the satellite across the chip. Measurement of satellite and star images, together with accurate timing of charge motion, provides accurate comparisons of lines of sight. Given lines of sight to stars near the satellite, the satellite line of sight may be determined. Initial experiments with this technique, using an 18 cm telescope, have produced TDRS-4 observations which have an rms error of 0.5 arc second, 100 m at synchronous altitude. Use of a mosaic of CCD chips, each having its own rate of charge motion, in the focal place of a telescope would allow point images of a geosynchronous satellite and of stars to be formed simultaneously in the same telescope. The line of sight of such a satellite could be measured relative to nearby star lines of sight with an accuracy of approximately 0.03 arc second. Development of a star catalog with 0.04 arc second rms accuracy and perhaps ten stars per square degree would allow determination of satellite lines of sight with 0.05 arc second rms absolute accuracy, corresponding to 10 m at synchronous altitude. Multiple station time transfers through a communications satellite can provide accurate distances from the satellite to the ground stations. Such observations can, if calibrated for delays, determine satellite orbits to an accuracy approaching 10 m rms.

Satellites for distress alerting and locating: Report by Interagency Committee for Search and Rescue Ad Hoc Working Group

NASA Technical Reports Server (NTRS)

Ehrlich, E.

1976-01-01

The background behind the congressional legislation that led to the requirement for the Emergency Locator Transmitter (ELT) and the Emergency Position-Indicating Radio Beacon (EPIRB) to be installed on certain types of aircraft and inspected marine vessels respectively is discussed. The DAL problem is discussed for existing ELT and EPIRB equipped aircraft and ships. It is recognized that the DAL requirement for CONUS and Alaska and the maritime regions are not identical. In order to address the serious DAL problem which currently exists in CONUS and Alaska, a low orbiting satellite system evolves as the most viable and cost effective alternative that satisfies the overall SAR system design requirements. A satellite system designed to meet the needs of the maritime regions could be either low orbiting or geostationary. The conclusions drawn from this report support the recommendation to proceed with the implementation of a SAR orbiting satellite system.

Navigation Performance of Global Navigation Satellite Systems in the Space Service Volume

NASA Technical Reports Server (NTRS)

Force, Dale A.

2013-01-01

This paper extends the results I reported at this year's ION International Technical Meeting on multi-constellation GNSS coverage by showing how the use of multi-constellation GNSS improves Geometric Dilution of Precision (GDOP). Originally developed to provide position, navigation, and timing for terrestrial users, GPS has found increasing use for in space for precision orbit determination, precise time synchronization, real-time spacecraft navigation, and three-axis attitude control of Earth orbiting satellites. With additional Global Navigation Satellite Systems (GNSS) coming into service (GLONASS, Galileo, and Beidou) and the development of Satellite Based Augmentation Services, it is possible to obtain improved precision by using evolving multi-constellation receiver. The Space Service Volume formally defined as the volume of space between three thousand kilometers altitude and geosynchronous altitude ((is) approximately 36,500 km), with the volume below three thousand kilometers defined as the Terrestrial Service Volume (TSV). The USA has established signal requirements for the Space Service Volume (SSV) as part of the GPS Capability Development Documentation (CDD). Diplomatic efforts are underway to extend Space service Volume commitments to the other Position, Navigation, and Timing (PNT) service providers in an effort to assure that all space users will benefit from the enhanced capabilities of interoperating GNSS services in the space domain.

[Theme Issue: Communications Satellites.

ERIC Educational Resources Information Center

Howkins, John, Ed.

1976-01-01

One section of this journal is devoted to issues involving broadcast satellites. Separate articles discuss the need for international planning of satellite broadcasting, decisions made at the 1971 World Administrative Radio Conference for Space Telecommunications, potential problems in satellite broadcasting, a series of proposals drawn up by the…

Satellite-Delivered Learning.

ERIC Educational Resources Information Center

Arnall, Gail C.

1987-01-01

Discusses the application of satellite information delivery to training. Describes a new trend, horizontal programming. Also discusses vertical programming and in-house production of training materials. Lists vendors of satellite-based training. (CH)

15 years in promoting the use of isotopic and nuclear technique for combating land degradation and soil erosion: the contribution of the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture

NASA Astrophysics Data System (ADS)

Mabit, Lionel; Toloza, Arsenio; Heng, Lee

2017-04-01

The world population will exceed 9 billion by the year 2050 and food production will need to be approximately doubled to meet this crucial demand. Most of this increase will occur in developing countries, where the majority of the population depends on agriculture and their land for their livelihoods. Reports from the Intergovernmental Panel on Climate Change (IPCC) predicted negative impact of climate change, threatening global food security. In addition, the intensification of agricultural activities has increased pressure on land and water resources, resulting in different forms of soil degradation, of which soil erosion and associated sedimentation are worsening. Worldwide economic costs of agricultural soil loss and associated sedimentation downstream have been estimated at US 400 billion per year. As a result of climate change, world average soil erosion is expected to further increase significantly. Adapting to climate change requires agricultural soil and water management practices that make agricultural production systems resilient to drought, floods and land degradation, to enhance the conservation of the natural resource base for sustainable upland farming. These current concerns with ensuring sustainable use and management of agroecosystems create an urgent need for reliable quantitative data on the extent and magnitude of soil resource degradation over several spatial and time scales to formulate sound policies and management measures. Integrated isotopic approaches can help in targeting adapted and effective soil-water conservation measures to control soil degradation and therefore contribute to positive feedback mechanisms to mitigate climate change impact on soil and water resources. Set up 60 years ago as the world's centre for cooperation in the nuclear field, the International Atomic Energy Agency (IAEA) promotes the safe, secure and peaceful use of nuclear technologies. Since the end of the 1990s, the Joint FAO/IAEA Division of Nuclear

Perl Tools for Automating Satellite Ground Systems

NASA Technical Reports Server (NTRS)

McLean, David; Haar, Therese; McDonald, James

2000-01-01

The freeware scripting language Pert offers many opportunities for automating satellite ground systems for new satellites as well as older, in situ systems. This paper describes a toolkit that has evolved from of the experiences gained by using Pert to automate the ground system for the Compton Gamma Ray Observatory (CGRO) and for automating some of the elements in the Earth Observing System Data and Operations System (EDOS) ground system at Goddard Space Flight Center (GSFC). CGRO is an older ground system that was forced to automate because of fund cuts. Three 8 hour shifts were cut back to one 8 hour shift, 7 days per week. EDOS supports a new mission called Terra, launched December 1999 that requires distribution and tracking of mission-critical reports throughout the world. Both of these ground systems use Pert scripts to process data and display it on the Internet as well as scripts to coordinate many of the other systems that make these ground systems work as a coherent whole. Another task called Automated Multimodal Trend Analysis System (AMTAS) is looking at technology for isolation and recovery of spacecraft problems. This effort has led to prototypes that seek to evaluate various tools and technology that meet at least some of the AMTAS goals. The tools, experiences, and lessons learned by implementing these systems are described here.

Measurement of ²²⁶Ra in soil from oil field: advantages of γ-ray spectrometry and application to the IAEA-448 CRM.

PubMed

Ceccatelli, A; Katona, R; Kis-Benedek, G; Pitois, A

2014-05-01

The analytical performance of gamma-ray spectrometry for the measurement of (226)Ra in TENORM (Technically Enhanced Naturally Occurring Radioactive Material) soil was investigated by the IAEA. Fast results were obtained for characterization and certification of a new TENORM Certified Reference Material (CRM), identified as IAEA-448 (soil from oil field). The combined standard uncertainty of the gamma-ray spectrometry results is of the order of 2-3% for massic activity measurement values ranging from 16500 Bq kg(-1) to 21500 Bq kg(-1). Methodologies used for the production and certification of the IAEA-448 CRM are presented. Analytical results were confirmed by alpha spectrometry. The "t" test showed agreement between alpha and gamma results at 95% confidence level. © 2013 Published by Elsevier Ltd.

Sentinels in the Sky: Weather Satellites.

ERIC Educational Resources Information Center

Haynes, Robert

This publication describes forecasting weather activity using satellites. Information is included on the development of weather satellites, the National Oceanic and Atmospheric Administration (NOAA) Satellite System (including the polar-orbiting satellites), and the Geostationary Operational Environmental Satellite (GOES). The publication…

Skeletal muscle satellite cells

NASA Technical Reports Server (NTRS)

Schultz, E.; McCormick, K. M.

1994-01-01

Evidence now suggests that satellite cells constitute a class of myogenic cells that differ distinctly from other embryonic myoblasts. Satellite cells arise from somites and first appear as a distinct myoblast type well before birth. Satellite cells from different muscles cannot be functionally distinguished from one another and are able to provide nuclei to all fibers without regard to phenotype. Thus, it is difficult to ascribe any significant function to establishing or stabilizing fiber type, even during regeneration. Within a muscle, satellite cells exhibit marked heterogeneity with respect to their proliferative behavior. The satellite cell population on a fiber can be partitioned into those that function as stem cells and those which are readily available for fusion. Recent studies have shown that the cells are not simply spindle shaped, but are very diverse in their morphology and have multiple branches emanating from the poles of the cells. This finding is consistent with other studies indicating that the cells have the capacity for extensive migration within, and perhaps between, muscles. Complexity of cell shape usually reflects increased cytoplasmic volume and organelles including a well developed Golgi, and is usually associated with growing postnatal muscle or muscles undergoing some form of induced adaptive change or repair. The appearance of activated satellite cells suggests some function of the cells in the adaptive process through elaboration and secretion of a product. Significant advances have been made in determining the potential secretion products that satellite cells make. The manner in which satellite cell proliferative and fusion behavior is controlled has also been studied. There seems to be little doubt that cellcell coupling is not how satellite cells and myofibers communicate. Rather satellite cell regulation is through a number of potential growth factors that arise from a number of sources. Critical to the understanding of this form

Emerging Technologies: Small Satellite and Associated TPED

NASA Astrophysics Data System (ADS)

Zitz, R.

2014-09-01

The 2010 National Space Policy directs the U.S. space community, comprised of the Department of Defense, Intelligence Community, Military Services and NASA to examine our nation's ability to conduct space-based ISR and communications even during a period of peer state and near peer state attacks intended to deny us our advantages we accrue from our use of space systems. DOD and the ICs past experience is largely one of building small numbers of extraordinarily capable and expensive (exquisite) satellites for communications and ISR. As potential adversaries continue to develop cyber-attack capabilities and have demonstrated an ability to kinetically attack spacecraft, the vulnerability of our architecture is now a serious concern. In addition, the sluggish U.S. economy, the draw down and pull back from a decade of combat operations, and other factors have combined to force a significant reduction in DOD and IC spending over the coming decade(s). Simultaneously, DOD and the IC have a growing awareness that the long lead times and long mission duration of the exquisite space assets can lead to fielding technologies that become obsolete and mission limiting. Some DOD and IC leaders are now examining alternative architectures to provide lower cost, flexible, more diverse and rapidly launchable space systems. Government leaders are considering commercially hosted payloads in geosynchronous orbits and smaller, lower cost, free flying government and commercial satellites in low earth orbits. Additional changes to the ground tasking, processing, exploitation and dissemination (TPED) systems would ensure small satellites have end-to-end mission capability and meet emerging needs such as ease of tasking, multi-INT processing, and more advanced distribution mechanisms (e.g., to users on the move). Today, a majority of agency leaders and their subordinate program managers remain convinced that only large, expensive systems can truly answer requirements and provide reliable

Utilizing a TDRS satellite for direct broadcast satellite-radio propagation experiments and demonstrations

NASA Technical Reports Server (NTRS)

Hollansworth, James E.

1993-01-01

The NASA/VOA Direct Broadcast Satellite-Radio (DBS-R) Program will be using a NASA Tracking Data Relay Satellite (TDRS) satellite at 62 deg. West longitude to conduct live satellite S-band propagation experiments and demonstrations of satellite sound broadcasting over the next two years (1993-1994). The NASA/VOA DBS-R program has applied intensive effort to garner domestic and international support for the DBS-R concept. An S-band DBS-R allocation was achieved for Region 2 at WARC-92 held in Spain. With this allocation, the DBS-R program now needs to conduct S-band propagation experiments and systems demonstrations that will assist in the development of planning approaches for the use of Broadcast Satellite Service (Sound) frequency bands prior to the planning conference called for by WARC-92. These activities will also support receiver concept development applied to qualities ranging from AM to Monophonic FM, Stereophonic FM, Monophonic CD, and Stereophonic CD quality.

Communications satellites - The experimental years

NASA Technical Reports Server (NTRS)

Edelson, B. I.

1983-01-01

Only eight years after the launc of Sputnik-1 by the Soviet Union, the first commercial satellite, 'Early Bird', entered service. In just twelve years commercial satellite service extended around the earth and became profitable. The reasons for the successful development of the communications satellite services in a comparatively short time are considered. These reasons are related to the presence of three ingredients, taking into account technology to create the system, communications requirements to form a market, and a management structure to implement the system. The formation of the concept of using earth orbiting satellites for telecommunications is discussed. It is pointed out that the years from 1958 to 1964 were the true 'experimental years' for satellite communications. The rapid development of technology during this crucial period is described, giving attention to passive satellites, active systems, and development satellites.

On-orbit checkout study. [for the synchronous meteorological satellite and the technology demonstration satellite

NASA Technical Reports Server (NTRS)

Pritchard, E. I.

1977-01-01

The spaceborne testing equipment carried by the orbiter and the measuring equipment onboard the satellite (telemetry) is tested to verify that each is operating satisfactorily. The satellite command system is also checked. Thermal stabilization with the satellite in the orbiter shadow is achieved in six to eight hours. Satellite subsystem tests are run, and thermal control by heaters is checked. Thermal stabilization with the satellite exposed to the sun (when the orbiter is in sunlight) is again achieved in an estimated six to eight hours. Subsystem tests are again run in the hot condition, and heat rejection tests are made.

Satellite communication antenna technology

NASA Technical Reports Server (NTRS)

Mittra, R. (Editor); Imbriale, W. A. (Editor); Maanders, E. J. (Editor)

1983-01-01

A general overview of current technology in the field of communication satellite antennas is presented. Among the topics discussed are: the design of multiple beam systems; frequency reuse; and polarization control of antenna measurements. Consideration is also given to: contour beam synthesis; dual shaped reflector synthesis; beam shaping; and offset reflector design. The applications of the above technologies to present and future generations of communications satellites is considered, with emphasis given to such systems as: the Intelsats; the Defense Satellite Communications System, (DSCS-III); Satellite Business System (SBS), and Comstar.

A Computationally Efficient Algorithm for Disturbance Cancellation to Meet the Requirements for Optical Payloads in Satellites

DTIC Science & Technology

2001-09-01

starting from the energy approach, but unfortunately the geometry assumed in their work does not apply to the hexapods available at the Satellite...harmonics multiple of 1Hz, which was the difference between the two frequencies. The two assigned frequencies were actually suppressed, but the energy ...Audio Processing, Vol. 3, No. 3, May 1995, pp. 217–222. [20] Li, D. and Salcudean, S. E., “Modeling, Simulation and Control of a Hidraulic Stewart Plat

A home away from home: challenges and opportunities in engineering in vitro muscle satellite cell niches

PubMed Central

Cosgrove, Benjamin D.; Sacco, Alessandra; Gilbert, Penney M.; Blau, Helen M.

2009-01-01

Satellite cells are skeletal muscle stem cells with a principal role in postnatal skeletal muscle regeneration. Satellite cells, like many tissue-specific adult stem cells, reside in a quiescent state in an instructive, anatomically defined niche. The satellite cell niche constitutes a distinct membrane-enclosed compartment within the muscle fiber, containing a diversity of biochemical and biophysical signals that influence satellite cell function. A major limitation to the study and clinical utility of satellite cells is that upon removal from the muscle fiber and plating in traditional plastic tissue culture platforms, their muscle stem cell properties are rapidly lost. Clearly, the maintenance of stem cell function is critically dependent on in vivo niche signals, highlighting the need to create novel in vitro microenvironments that allow for the maintenance and propagation of satellite cells while retaining their potential to function as muscle stem cells. Here, we discuss how emerging biomaterials technologies offer great promise for engineering in vitro microenvironments to meet these challenges. In engineered biomaterials, signaling molecules can be presented in a manner that more closely mimics cell-cell and cell-matrix interactions and matrices can be fabricated with diverse rigidities that approximate in vivo tissues. The development of in vitro microenvironments in which niche features can be systematically modulated will be instrumental not only to future insights into muscle stem cell biology and therapeutic approaches to muscle diseases and muscle wasting with aging, but also will provide a paradigm for the analysis of numerous adult tissue-specific stem cells. PMID:19751902

Nonlinear Dynamics of Formation of Drops of Non-Newtonian Liquids from Capillaries: Satellite Formation and Flow Transitions

NASA Astrophysics Data System (ADS)

Yildirim, Ozgur E.; Basaran, Osman A.

1999-11-01

Drop formation from capillaries, and the often undesired phenomenon of satellite generation, play a central role in diverse applications including ink-jet printing, biochip processors, and spray coating, where the working fluid is usually non-Newtonian. Although some work has been done in related areas, the phenomenon of meetings.html>formation of drops of non--Newtonian fluids from capillaries has remained largely unexplored. Here a theoretical approach is adopted to study the dripping of axisymmetric drops of non--Newtonian liquids from capillaries. The constitutive equation used accounts for both shear thinning and strain hardening. First, regular perturbation theory is utilized to reduce the spatial dimension of the governing equations to one. The computations rely on Galerkin/finite element analysis with adaptive finite differencing for time integration. meetings.html>The dynamics are followed beyond the first breakup to investigate conditions for occurrence of satellites. Effect of increasing flow rate is also studied to uncover transitions that occur as one moves from a regime of periodic drop formation to one of jetting.

Satellite Communications for ATM

NASA Technical Reports Server (NTRS)

Shamma, Mohammed A.

2003-01-01

This presentation is an overview on Satellite Communication for the Aeronautical Telecommunication Management (ATM) research. Satellite Communications are being considered by the FAA and NASA as a possible alternative to the present and future ground systems supporting Air Traffic Communications. The international Civil Aviation Organization (ICAO) have in place Standards and Recommended Practices (SARPS) for the Aeronautical Mobile Satellite Services (AMSS) which is mainly derived from the pre-existing Inmarsat service that has been in service since the 1980s. The Working Group A of the Aeronautical Mobile Communication Panel of ICAO has also been investigating SARPS for what is called the Next Generation Satellite Service (NGSS) which conforms less to the Inmarsat based architecture and explores wider options in terms of satellite architectures. Several designs are being proposed by Firms such as Boeing, ESA, NASA that are geared toward full or secondary usage of satellite communications for ATM. Satellite communications for ATM can serve several purposes ranging from primary usage where ground services would play a minimal backup role, to an integrated solution where it will be used to cover services, or areas that are less likely to be supported by the proposed and existing ground infrastructure. Such Integrated roles can include usage of satellite communications for oceanic and remote land areas for example. It also can include relieving the capacity of the ground network by providing broadcast based services of Traffic Information Services messages (TIS-B), or Flight Information Services (FIS-B) which can take a significant portion of the ground system capacity. Additionally, satellite communication can play a backup role to support any needs for ground replacement, or additional needed capacity even after the new digital systems are in place. The additional bandwidth that can be provided via satellite communications can also open the door for many new

Laser Geodynamics Satellite (LAGEOS)

NASA Image and Video Library

2016-05-04

This 1975 NASA video highlights the development of LAser GEOdynamics Satellite (LAGEOS I) developed at NASA's Marshall Space Flight Center in Huntsville, Alabama. LAGEOS I is a passive satellite constructed from brass and aluminum and contains 426 individual precision reflectors made from fused silica glass. The mirrored surface of the satellite was designed to reflect laser beams from ground stations for accurate ranging measurements. LAGEOS I was launched on May 4, 1976 from Vandenberg Air Force Base, California. The two-foot diameter, 900-pound satellite orbited the Earth from pole to pole, measuring the movements of the Earth's surface relative to earthquakes, continental drift, and other geophysical phenomena. Scientists at NASA's Marshall Space Flight Center in Huntsville, Alabama came up with the idea for the satellite and built it at the Marshall Center.

Full Service ISDN Satellite (FSIS) network model for advanced ISDN satellite design and experiments

NASA Technical Reports Server (NTRS)

Pepin, Gerard R.

1992-01-01

The Full Service Integrated Services Digital Network (FSIS) network model for advanced satellite designs describes a model suitable for discrete event simulations. A top down model design uses the Advanced Communications Technology Satellite (ACTS) as its basis. The ACTS and the Interim Service ISDN Satellite (ISIS) perform ISDN protocol analyses and switching decisions in the terrestrial domain, whereas FSIS makes all its analyses and decisions on-board the ISDN satellite.

Papers arising from IAEA Coordinated Research Project "Utilization of ion accelerators for studying and modelling of radiation induced defects in semiconductors and insulators" (F11016)

NASA Astrophysics Data System (ADS)

Vittone, Ettore; Breese, Mark; Simon, Aliz

2016-04-01

Within the International Atomic Energy Agency (IAEA) Department of Nuclear Sciences and Applications, activities are carried out to assist and advise IAEA Member States in assessing their needs for capacity building, research and development in nuclear sciences. Support is also provided to Member States' activities geared towards deriving benefits in fields such as (i) advanced materials for nuclear applications, (ii) application of accelerators and associated instrumentation, and (iii) nuclear, atomic and molecular data. One of the means that the IAEA uses to deliver its programme is Coordinated Research Projects (CRPs) which are very effective in stimulating international research and scientific interaction among the Member States.

ADA, the Programming Language of Choice for the UPMSat-2 Satellite

NASA Astrophysics Data System (ADS)

Garrido, Jorge; Zamorano, Juan; de la Puente, Juan A.; Alonso, Alejandro; Salazar, Emilio

2015-09-01

The proper selection of development mechanisms and tools is essential for the final success of any engineering project. This is also true when it comes to software development. Furthermore, when the system shows very specific and hard to meet requirements, as it happens for high-integrity real-time systems, the appropriate selection is crucial. For this kind of systems, Ada has proven to be a successful companion, and satellites are not an exception. The paper presents the reasons behind the selection of Ada for the UPMSat-2 development, along with the experience and examples on its usage.

IMS/Satellite Situation Center report

NASA Technical Reports Server (NTRS)

1973-01-01

Services planned by the Satellite Situation Center during the International Magnetospheric Study are briefly described. User requirements are emphasized. The following data are presented: orbital parameters for ISIS 2, ESRO 4, and HEOS 2; entry exit times for highly elliptical satellites; plots for highly elliptical earth satellites; and plots and flux tube intersection for low altitude satellites.

Real-time estimation of BDS/GPS high-rate satellite clock offsets using sequential least squares

NASA Astrophysics Data System (ADS)

Fu, Wenju; Yang, Yuanxi; Zhang, Qin; Huang, Guanwen

2018-07-01

The real-time precise satellite clock product is one of key prerequisites for real-time Precise Point Positioning (PPP). The accuracy of the 24-hour predicted satellite clock product with 15 min sampling interval and an update of 6 h provided by the International GNSS Service (IGS) is only 3 ns, which could not meet the needs of all real-time PPP applications. The real-time estimation of high-rate satellite clock offsets is an efficient method for improving the accuracy. In this paper, the sequential least squares method to estimate real-time satellite clock offsets with high sample rate is proposed to improve the computational speed by applying an optimized sparse matrix operation to compute the normal equation and using special measures to take full advantage of modern computer power. The method is first applied to BeiDou Navigation Satellite System (BDS) and provides real-time estimation with a 1 s sample rate. The results show that the amount of time taken to process a single epoch is about 0.12 s using 28 stations. The Standard Deviation (STD) and Root Mean Square (RMS) of the real-time estimated BDS satellite clock offsets are 0.17 ns and 0.44 ns respectively when compared to German Research Center for Geosciences (GFZ) final clock products. The positioning performance of the real-time estimated satellite clock offsets is evaluated. The RMSs of the real-time BDS kinematic PPP in east, north, and vertical components are 7.6 cm, 6.4 cm and 19.6 cm respectively. The method is also applied to Global Positioning System (GPS) with a 10 s sample rate and the computational time of most epochs is less than 1.5 s with 75 stations. The STD and RMS of the real-time estimated GPS satellite clocks are 0.11 ns and 0.27 ns, respectively. The accuracies of 5.6 cm, 2.6 cm and 7.9 cm in east, north, and vertical components are achieved for the real-time GPS kinematic PPP.

Estimating Density Using Precision Satellite Orbits from Multiple Satellites

NASA Astrophysics Data System (ADS)

McLaughlin, Craig A.; Lechtenberg, Travis; Fattig, Eric; Krishna, Dhaval Mysore

2012-06-01

This article examines atmospheric densities estimated using precision orbit ephemerides (POE) from several satellites including CHAMP, GRACE, and TerraSAR-X. The results of the calibration of atmospheric densities along the CHAMP and GRACE-A orbits derived using POEs with those derived using accelerometers are compared for various levels of solar and geomagnetic activity to examine the consistency in calibration between the two satellites. Densities from CHAMP and GRACE are compared when GRACE is orbiting nearly directly above CHAMP. In addition, the densities derived simultaneously from CHAMP, GRACE-A, and TerraSAR-X are compared to the Jacchia 1971 and NRLMSISE-00 model densities to observe altitude effects and consistency in the offsets from the empirical models among all three satellites.

JEMRMS Small Satellite Deployment Observation

NASA Image and Video Library

2012-10-04

ISS033-E-009334 (4 Oct. 2012) --- Several tiny satellites are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module’s robotic arm on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment.

JEMRMS Small Satellite Deployment Observation

NASA Image and Video Library

2012-10-04

ISS033-E-009458 (4 Oct. 2012) --- Several tiny satellites are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module’s robotic arm on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment.

NPP Satellite Launch

NASA Image and Video Library

2011-10-28

The Satellite Operations Facility of the National Oceanic and Atmospheric Administration (NOAA) is seen here minutes before the launch of the National Polar-orbiting Operational Environmental Satellite System Preparatory Project (NPP) on Friday, Oct. 28, 2011 in Suitland, Md. NPP is a joint venture between NASA and NOAA, and is the nation's newest Earth-observing satellite, which will provide data on climate change science, allow for accurate weather forecasts and advance warning for severe weather. NPP was launched from Vandenberg Air Force Base in California. Photo Credit: (NASA/Carla Cioffi)

TU-AB-BRC-07: Efficiency of An IAEA Phase-Space Source for a Low Energy X-Ray Tube Using Egs++

DOE Office of Scientific and Technical Information (OSTI.GOV)

Watson, PGF; Renaud, MA; Seuntjens, J

Purpose: To extend the capability of the EGSnrc C++ class library (egs++) to write and read IAEA phase-space files as a particle source, and to assess the relative efficiency gain in dose calculation using an IAEA phase-space source for modelling a miniature low energy x-ray source. Methods: We created a new ausgab object to score particles exiting a user-defined geometry and write them to an IAEA phase-space file. A new particle source was created to read from IAEA phase-space data. With these tools, a phase-space file was generated for particles exiting a miniature 50 kVp x-ray tube (The INTRABEAM System,more » Carl Zeiss). The phase-space source was validated by comparing calculated PDDs with a full electron source simulation of the INTRABEAM. The dose calculation efficiency gain of the phase-space source was determined relative to the full simulation. The efficiency gain as a function of i) depth in water, and ii) job parallelization was investigated. Results: The phase-space and electron source PDDs were found to agree to 0.5% RMS, comparable to statistical uncertainties. The use of a phase-space source for the INTRABEAM led to a relative efficiency gain of greater than 20 over the full electron source simulation, with an increase of up to a factor of 196. The efficiency gain was found to decrease with depth in water, due to the influence of scattering. Job parallelization (across 2 to 256 cores) was not found to have any detrimental effect on efficiency gain. Conclusion: A set of tools has been developed for writing and reading IAEA phase-space files, which can be used with any egs++ user code. For simulation of a low energy x-ray tube, the use of a phase-space source was found to increase the relative dose calculation efficiency by factor of up to 196. The authors acknowledge partial support by the CREATE Medical Physics Research Training Network grant of the Natural Sciences and Engineering Research Council (Grant No. 432290).« less

Space satellite power system. [conversion of solar energy by photovoltaic solar cell arrays

NASA Technical Reports Server (NTRS)

Glaser, P. E.

1974-01-01

The concept of a satellite solar power station was studied. It is shown that it offers the potential to meet a significant portion of future energy needs, is pollution free, and is sparing of irreplaceable earth resources. Solar energy is converted by photovoltaic solar cell arrays to dc energy which in turn is converted into microwave energy in a large active phased array. The microwave energy is beamed to earth with little attenuation and is converted back to dc energy on the earth. Economic factors are considered.

UO 2 Particle Standards: Synthesis, Purification & Planchet Preparation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barrett, Christopher A.; Anheier, Norman C.

2016-03-31

The IAEA has previously indicated its desire for reliable provision of suitable reference materials in support of environmental sample analysis and sustained advancement at the Department of Safeguards, as laid out in the Long Term R&D plan (LTRD 10.1 & 10.2). In a recent meeting between NPAC, the IAEA and PNNL, this pressing need was directly outlined by the IAEA as having two main objectives. The first pertains to current operations, such as instrument calibrations and evaluation of bias across the Network of Analytical Laboratories and requires particles on the order of 300-500 nm in diameter. The second need formore » particle reference material would directly support the IAEA’s ongoing R&D efforts and calls for smaller particles ranging from 50 -100 nm in size. As such, the IAEA has expressed a great deal of interest in the newly established synthesis capabilities at PNNL, initially cultivated through a PNNL LDRD project to address the particle-standards shortcomings for uranium oxide material. The joint meeting concluded with a request by the IAEA for 1-2 planchet samples containing PNNL’s UO 2 particulate material, to be delivered in the near-term. This report outlines the steps taken to meet that request and includes some basic characteristics of the samples sent to the IAEA.« less

Methods of satellite oceanography

NASA Technical Reports Server (NTRS)

Stewart, R. H.

1985-01-01

The theoretical basis for remote sensing measurements of climate and ocean dynamics is examined. Consideration is given to: the absorption of electromagnetic radiation in the atmosphere; scattering in the atmosphere; and satellite observations using visible light. Consideration is also given to: the theory of radio scatter from the sea; scatter of centimeter waves from the sea; and the theory of operation of synthetic aperture radars. Additional topics include: the coordinate systems of satellite orbits for oceanographic remote sensing applications; the operating features of the major U.S. satellite systems for viewing the ocean; and satellite altimetry.

Echo 30" Sub Satellite

NASA Image and Video Library

2012-09-07

James Hansen describes the work on Project Echo s air density experiment known as the Sub-Satellite. Before launch engineers subjected the sub-satellite to many tests. Here, the sub-satellite is shown prior to tests to determine the capacity of the 30-inch Sub-Satellite to withstand the high temperature of direct sunlight in space, Langley researchers subjected it to 450 F heat test. Results indicated that the aluminum-covered Mylar plastic would effectively reflect the dangerous heat. -- Published in James R. Hansen, Spaceflight Revolution: NASA Langley Research Center From Sputnik to Apollo, NASA SP-4308, p. 168.

The standardized functional support sectional for the Small Astronomy Satellite (SAS)

NASA Technical Reports Server (NTRS)

Townsend, M. R.

1974-01-01

The standardized functional support section for the improved Small Astronomy Satellite (SAS) spacecraft, which can be used virtually without change for a wide variety of experimental packages and missions, is described. This functional support section makes the spacecraft remarkably flexible for a small satellite. Able to point its thrust axis to any direction in space, it can also spin or slow its outer body rotation to zero for star- or earth-locked pointing of side-viewing experiments. It features a reprogrammable telemetry system, a delayed command system, and an improved control system. Experiments can be built independently and attached to the SAS spacecraft just prior to final acceptance testing and launch. The spacecraft subsystems are described in detail. Included are a summary of the spacecraft characteristics, special design considerations, project reliability requirements, and environmental test conditions. It is intended that this new functional support section afford virtual off-the-shelf availability of the SAS spacecraft to independently built experiments, thus providing quick response time and minimum cost in meeting a wide variety of experimenter needs.

Tracking and Data Relay Satellite (TDRS-3) Range Biases and Momentum Unload Modeling for Terra (EOS-AMI)

NASA Technical Reports Server (NTRS)

Ward, Douglas T.

2001-01-01

The Flight Dynamics Facility (FDF) reports its performance in meeting Tracking and Data Relay Satellite (TDRS) predicted ephemeris accuracy requirements with TDRS-3. The Terra (Earth Observing System AM-1) satellite has 3-sigma TDRS requirements of 75 m for total position accuracy predicted over one day onboard. The study sample includes selected cases over 21 months after Guam Remote Ground Terminal (GRGT) support started in June 1998. For daily solutions with a 1.5-day prediction span, predicted results of the study were below the Terra requirement by at least 12 m. Refined range bias estimation and modeled momentum unloads are needed to meet Terra's requirements for TDRS-3. Maintained at 275 W longitude over the zone of exclusion, TDRS-3 is analyzed separately from other TDRSs because of its unique tracking data. Only the Bilateration Ranging Transponder (BRT) at Alice Springs (ALS), Australia, and the Telemetry, Tracking and Command (TT&C) system at Guam are used for routine operational tracking data for TDRS-3. Simultaneous batch orbit solutions with three TDRSs and either the Compton Gamma Ray Observatory (GRO) or Terra were done with the Goddard Trajectory Determination System (GTDS) to periodically refine the TT&C and BRT System (BRTS) range biases. As new biases were determined, significant changes were made in estimating the absolute position. FDF achieved similar results using a sequential filter with all operational TDRSs and four user satellites. Definitive accuracy (3-sigma) is expected to be below 50 m. The White Sands Complex (WSC) performs momentum unloads to maintain three-axis stabilized attitude of TDRSs. The relationship between velocity changes (delta-V) and reaction wheel speed changes was empirically determined for roll/yaw unloads. A theoretical relationship was verified and used for pitch unloads. Modeling both pitch and roll/yaw momentum unloads is necessary to meet the 75-m requirement. Moving the orbit solution epoch an hour before a

Combined Global Navigation Satellite Systems in the Space Service Volume

NASA Technical Reports Server (NTRS)

Force, Dale A.; Miller, James J.

2013-01-01

Besides providing position, velocity, and timing (PVT) for terrestrial users, the Global Positioning System (GPS) is also being used to provide PVT information for earth orbiting satellites. In 2006, F. H. Bauer, et. al., defined the Space Service Volume in the paper GPS in the Space Service Volume , presented at ION s 19th international Technical Meeting of the Satellite Division, and looked at GPS coverage for orbiting satellites. With GLONASS already operational, and the first satellites of the Galileo and Beidou/COMPASS constellations already in orbit, it is time to look at the use of the new Global Navigation Satellite Systems (GNSS) coming into service to provide PVT information for earth orbiting satellites. This presentation extends GPS in the Space Service Volume by examining the coverage capability of combinations of the new constellations with GPS GPS was first explored as a system for refining the position, velocity, and timing of other spacecraft equipped with GPS receivers in the early eighties. Because of this, a new GPS utility developed beyond the original purpose of providing position, velocity, and timing services for land, maritime, and aerial applications. GPS signals are now received and processed by spacecraft both above and below the GPS constellation, including signals that spill over the limb of the earth. Support of GPS space applications is now part of the system plan for GPS, and support of the Space Service Volume by other GNSS providers has been proposed to the UN International Committee on GNSS (ICG). GPS has been demonstrated to provide decimeter level position accuracy in real-time for satellites in low Earth orbit (centimeter level in non-real-time applications). GPS has been proven useful for satellites in geosynchronous orbit, and also for satellites in highly elliptical orbits. Depending on how many satellites are in view, one can keep time locked to the GNSS standard, and through that to Universal Time as long as at least one

The Eccentric Satellites Problem: Comparing Milky Way Satellite Orbital Properties to Simulation Results

NASA Astrophysics Data System (ADS)

Haji, Umran; Pryor, Carlton; Applebaum, Elaad; Brooks, Alyson

2018-01-01

We compare the orbital properties of the satellite galaxies of the Milky Way to those of satellites found in simulated Milky Way-like systems as a means of testing cosmological simulations of galaxy formation. The particular problem that we are investigating is a discrepancy in the distribution of orbital eccentricities. Previous studies of Milky Way-mass systems analyzed in a semi-analytic ΛCDM cosmological model have found that the satellites tend to have significantly larger fractions of their kinetic energy invested in radial motion with respect to their central galaxy than do the real-world Milky Way satellites. We analyze several high-resolution ("zoom-in") hydrodynamical simulations of Milky Way-mass galaxies and their associated satellite systems to investigate why previous works found Milky Way-like systems to be rare. We find a possible relationship between a quiescent galactic assembly history and a distribution of satellite kinematics resembling that of the Milky Way. This project has been supported by funding from National Science Foundation grant PHY-1560077.

Seabed gamma-ray spectrometry: applications at IAEA-MEL.

PubMed

Osvath, I; Povinec, P P

2001-01-01

The technique of underwater gamma-ray spectrometry has been developed to complement or replace the traditional sampling-sample analysis approach for applications with space-time constraints, e.g. large areas of investigation, emergency response or long-term monitoring. IAEA-MEL has used both high-efficiency NaI(Tl) and high-resolution HPGe spectrometry to investigate contamination with anthropogenic radionuclides in a variety of marine environments. Surveys at the South Pacific nuclear test sites of Mururoa and Fangataufa have been used to guide sampling in areas of high contamination around ground zero points. In the Irish Sea offshore from the Sellafield nuclear reprocessing plant, a gamma-ray survey of seabed sediment was carried out to obtain estimates of the distribution and subsequently, for the inventory of 137Cs in the investigated area.

Roi-Orientated Sensor Correction Based on Virtual Steady Reimaging Model for Wide Swath High Resolution Optical Satellite Imagery

NASA Astrophysics Data System (ADS)

Zhu, Y.; Jin, S.; Tian, Y.; Wang, M.

2017-09-01

To meet the requirement of high accuracy and high speed processing for wide swath high resolution optical satellite imagery under emergency situation in both ground processing system and on-board processing system. This paper proposed a ROI-orientated sensor correction algorithm based on virtual steady reimaging model for wide swath high resolution optical satellite imagery. Firstly, the imaging time and spatial window of the ROI is determined by a dynamic search method. Then, the dynamic ROI sensor correction model based on virtual steady reimaging model is constructed. Finally, the corrected image corresponding to the ROI is generated based on the coordinates mapping relationship which is established by the dynamic sensor correction model for corrected image and rigours imaging model for original image. Two experimental results show that the image registration between panchromatic and multispectral images can be well achieved and the image distortion caused by satellite jitter can be also corrected efficiently.

Compositional Analyses and Implications of Visible/Near-Infrared Spectra of Outer Irregular Jovian Satellites

NASA Astrophysics Data System (ADS)

Vilas, Faith; Hendrix, Amanda

2017-10-01

The existence of a visible-near infrared absorption feature attributed to aqueous alteration products has been suggested in both grey and reddened broadband photometry of some outer irregular jovian satellites. Moderate resolution VNIR narrowband spectroscopy was obtained of the jovian irregular satellites JVI Himalia, JVII Elara, JVIII Pasiphae, JIX Sinope, JX Lysithea, JXI Carme, JXII Ananke and JXVII Callirrhoe in 2006, 2008, 2009, and 2010 using the MMT Observatory facility Red Channel spectrograph to confirm the presence of this feature. The spectra are centered near 0.64 μm in order to cover the 0.7-μm feature entirely (generally ranging from 0.57 to 0.83 μm). The spectra generally have a dispersion/element of ~0.6 nm (6Å) some spectra are smoothed. These spectra sample three prograde (i = 28o), four retrograde (i = 149o, 165o) and one independent satellite.We observe these findings among the spectra:- An absorption feature centered near 0.7 µm exists in the spectra of the three prograde (i = 28o) satellites. This feature is spectrally broader than the 0.7-µm feature observed in C-complex asteroids. None appears spectrally reddened. This suggests that these prograde satellites have a common parent body.- A different absorption feature appears in the spectra of the three retrograde (i = 149o) satellites, also suggesting a common parent body. Varying reddening is observed. This feature is similar in spectral location and width to the 0.7-µm feature.- Reddening is observed in the individual observation of JXI Carme (i = 165o), and independent satellite JIX Sinope, similar to the D-class asteroid spectra dominating the Trojan population. A suggested absorption feature is being investigated.Mixing modeling of combinations of both expected and proposed compositions including carbonaceous materials, phyllosilicates, mafic silicates, and other opaque materials, is currently underway. Results will be reported and discussed at the meeting.Acknowledgments: The

Epos TCS Satellite Data

NASA Astrophysics Data System (ADS)

Manunta, Michele; Mandea, Mioara; Fernández-Turiel, José Luis; Stramondo, Salvatore; Wright, Tim; Walter, Thomas; Bally, Philippe; Casu, Francesco; Zeni, Giovanni; Buonanno, Sabatino; Zinno, Ivana; Tizzani, Pietro; Castaldo, Raffaele; Ostanciaux, Emilie; Diament, Michel; Hooper, Andy; Maccaferri, Francesco; Lanari, Riccardo

2016-04-01

TCS Satellite Data is devoted to provide Earth Observation (EO) services, transversal with respect to the large EPOS community, suitable to be used in several application scenarios. In particular, the main goal is to contribute with mature services that have already well demonstrated their effectiveness and relevance in investigating the physical processes controlling earthquakes, volcanic eruptions and unrest episodes as well as those driving tectonics and Earth surface dynamics. The TCS Satellite Data will provide two kinds of services: satellite products/services, and Value-added satellite products/services. The satellite products/services are composed of three (EPOSAR, GDM and COMET) well-identified and partly already operational elements for delivering Level 1 products. Such services will be devoted to the generation of SAR interferograms, DTM and ground displacement maps through the exploitation of different advanced EO techniques for InSAR and optical data analysis. The Value-added satellite products/services are composed of 4 elements (EPOSAR, 3D-Def, Mod and COMET) of Level 2 and 3 products. Such services integrate satellite and in situ measurements and observations to retrieve information on source mechanism, such as the geometry (spatial location, depth, volume changes) and the physical parameters of the deformation sources, through the exploitation of modelling approaches. The TCS Satellite Data will provide products in two different processing and delivery modes: 1- surveillance mode - routinely product generation; 2- on demand mode - product generation performed on demand by the user. Concerning the surveillance mode, the goal is providing continuous satellite measurements in areas of particular interest from a geophysical perspective (supersites). The objective is the detection of displacement patterns changing along time and their geophysical explanation. This is a valid approach for inter-seismic movements and volcanic unrest, post-seismic and post

ACTS Satellite Telemammography Network Experiments

NASA Technical Reports Server (NTRS)

Kachmar, Brian A.; Kerczewski, Robert J.

2000-01-01

The Satellite Networks and Architectures Branch of NASA's Glenn Research Center has developed and demonstrated several advanced satellite communications technologies through the Advanced Communications Technology Satellite (ACTS) program. One of these technologies is the implementation of a Satellite Telemammography Network (STN) encompassing NASA Glenn, the Cleveland Clinic Foundation. the University of Virginia, and the Ashtabula County Medical Center. This paper will present a look at the STN from its beginnings to the impact it may have on future telemedicine applications. Results obtained using the experimental ACTS satellite demonstrate the feasibility of Satellite Telemammography. These results have improved teleradiology processes and mammography image manipulation, and enabled advances in remote screening methodologies. Future implementation of satellite telemammography using next generation commercial satellite networks will be explored. In addition, the technical aspects of the project will be discussed, in particular how the project has evolved from using NASA developed hardware and software to commercial off the shelf (COTS) products. Development of asymmetrical link technologies was an outcome of this work. Improvements in the display of digital mammographic images, better understanding of end-to-end system requirements, and advances in radiological image compression were achieved as a result of the research. Finally, rigorous clinical medical studies are required for new technologies such as digital satellite telemammography to gain acceptance in the medical establishment. These experiments produced data that were useful in two key medical studies that addressed the diagnostic accuracy of compressed satellite transmitted digital mammography images. The results of these studies will also be discussed.

Satellite switched FDMA advanced communication technology satellite program

NASA Technical Reports Server (NTRS)

Atwood, S.; Higton, G. H.; Wood, K.; Kline, A.; Furiga, A.; Rausch, M.; Jan, Y.

1982-01-01

The satellite switched frequency division multiple access system provided a detailed system architecture that supports a point to point communication system for long haul voice, video and data traffic between small Earth terminals at Ka band frequencies at 30/20 GHz. A detailed system design is presented for the space segment, small terminal/trunking segment at network control segment for domestic traffic model A or B, each totaling 3.8 Gb/s of small terminal traffic and 6.2 Gb/s trunk traffic. The small terminal traffic (3.8 Gb/s) is emphasized, for the satellite router portion of the system design, which is a composite of thousands of Earth stations with digital traffic ranging from a single 32 Kb/s CVSD voice channel to thousands of channels containing voice, video and data with a data rate as high as 33 Mb/s. The system design concept presented, effectively optimizes a unique frequency and channelization plan for both traffic models A and B with minimum reorganization of the satellite payload transponder subsystem hardware design. The unique zoning concept allows multiple beam antennas while maximizing multiple carrier frequency reuse. Detailed hardware design estimates for an FDMA router (part of the satellite transponder subsystem) indicate a weight and dc power budget of 353 lbs, 195 watts for traffic model A and 498 lbs, 244 watts for traffic model B.

Land mobile satellite propagation measurements in Japan using ETS-V satellite

NASA Technical Reports Server (NTRS)

Obara, Noriaki; Tanaka, Kenji; Yamamoto, Shin-Ichi; Wakana, Hiromitsu

1993-01-01

Propagation characteristics of land mobile satellite communications channels have been investigated actively in recent years. Information of propagation characteristics associated with multipath fading and shadowing is required to design commercial land mobile satellite communications systems, including protocol and error correction method. CRL (Communications Research Laboratory) has carried out propagation measurements using the Engineering Test Satellite-V (ETS-V) at L band (1.5 GHz) through main roads in Japan by a medium gain antenna with an autotracking capability. This paper presents the propagation statistics obtained in this campaign.

Development of HWIL Testing Capabilities for Satellite Target Emulation at AEDC

NASA Astrophysics Data System (ADS)

Lowry, H.; Crider, D.; Burns, J.; Thompson, R.; Goldsmith, G., II; Sholes, W.

capable of providing the simulation of satellites as well. There may also be a need for greater radiometric intensity or shorter time response. An appropriate satellite model is integral to the scene generation process to meet the requirements of SSA programs. The Kinetic Kill Vehicle Hardware-in-the-Loop Simulator (KHILS) facility and the Guided Weapons Evaluation Facility (GWEF), both at Eglin Air Force Base, FL are assisting in developing the scene projection hardware, based on their significant test experience using resistive emitter arrays to test interceptors in a real-time environment. Army Aviation and Missile Research & Development Command (AMRDEC) will develop the Scene Generation System for the real-time mission simulation.

Attitude Control and Orbital Dynamics Challenges of Removing the First 3-Axis Stabilized Tracking and Data Relay Satellite from the Geosynchronous ARC

NASA Technical Reports Server (NTRS)

Benet, Charles A.; Hofman, Henry; Williams, Thomas E.; Olney, Dave; Zaleski, Ronald

2011-01-01

Launched on April 4, 1983 onboard STS 6 (Space Shuttle Challenger), the First Tracking and Data Relay Satellite (TDRS 1) was retired above the Geosynchronous Orbit (GEO) on June 27, 2010 after having provided real-time communications with a variety of low-orbiting spacecraft over a 26-year period. To meet NASA requirements limiting orbital debris 1, a team of experts was assembled to conduct an End-Of-Mission (EOM) procedure to raise the satellite 350 km above the GEO orbit. Following the orbit raising via conventional station change maneuvers, the team was confronted with having to deplete the remaining propellant and passivate all energy storage or generation sources. To accomplish these tasks within the time window, communications (telemetry and control links), electrical power, propulsion, and thermal constraints, a spacecraft originally designed as a three-axis stabilized satellite was turned into a spinner. This paper (a companion paper to Innovative Approach Enabled the Retirement of TDRS 1, paper # 1699, IEEE 2011 Aerospace Conference, March 5-12, 2011 sup 2) focuses on the challenges of maintaining an acceptable spinning dynamics, while repetitively firing thrusters. Also addressed are the effects of thruster firings on the orbit characteristics and how they were mitigated by a careful scheduling of the fuel depletion operations. Periodic thruster firings for spin rate adjustment, nutation damping, and precession of the momentum vector were also required in order to maintain effective communications with the satellite. All operations were thoroughly rehearsed and supported by simulations thus lending a high level of confidence in meeting the NASA EOM goals.

Geometrical-Based Navigation System Performance Assessment in the Space Service Volume Using a Multiglobal Navigation Satellite System Methodology

NASA Technical Reports Server (NTRS)

Welch, Bryan W.

2016-01-01

NASA is participating in the International Committee on Global Navigation Satellite Systems (GNSS) (ICG)'s efforts towards demonstrating the benefits to the space user in the Space Service Volume (SSV) when a multi-GNSS solution space approach is utilized. The ICG Working Group: Enhancement of GNSS Performance, New Services and Capabilities has started a three phase analysis initiative as an outcome of recommendations at the ICG-10 meeting, in preparation for the ICG-11 meeting. The first phase of that increasing complexity and fidelity analysis initiative is based on a pure geometrically-derived access technique. The first phase of analysis has been completed, and the results are documented in this paper.

An aeronautical mobile satellite experiment

NASA Technical Reports Server (NTRS)

Jedrey, T. C.; Dessouky, K. I.; Lay, N. E.

1990-01-01

The various activities and findings of a NASA/FAA/COMSAT/INMARSAT collaborative aeronautical mobile satellite experiment are detailed. The primary objective of the experiment was to demonstrate and evaluate an advanced digital mobile satellite terminal developed at the Jet Propulsion Laboratory under the NASA Mobile Satellite Program. The experiment was a significant milestone for NASA/JPL, since it was the first test of the mobile terminal in a true mobile satellite environment. The results were also of interest to the general mobile satellite community because of the advanced nature of the technologies employed in the terminal.

Stereoscopic observations from meteorological satellites

NASA Astrophysics Data System (ADS)

Hasler, A. F.; Mack, R.; Negri, A.

The capability of making stereoscopic observations of clouds from meteorological satellites is a new basic analysis tool with a broad spectrum of applications. Stereoscopic observations from satellites were first made using the early vidicon tube weather satellites (e.g., Ondrejka and Conover [1]). However, the only high quality meteorological stereoscopy from low orbit has been done from Apollo and Skylab, (e.g., Shenk et al. [2] and Black [3], [4]). Stereoscopy from geosynchronous satellites was proposed by Shenk [5] and Bristor and Pichel [6] in 1974 which allowed Minzner et al. [7] to demonstrate the first quantitative cloud height analysis. In 1978 Bryson [8] and desJardins [9] independently developed digital processing techniques to remap stereo images which made possible precision height measurement and spectacular display of stereograms (Hasler et al. [10], and Hasler [11]). In 1980 the Japanese Geosynchronous Satellite (GMS) and the U.S. GOES-West satellite were synchronized to obtain stereo over the central Pacific as described by Fujita and Dodge [12] and in this paper. Recently the authors have remapped images from a Low Earth Orbiter (LEO) to the coordinate system of a Geosynchronous Earth Orbiter (GEO) and obtained stereoscopic cloud height measurements which promise to have quality comparable to previous all GEO stereo. It has also been determined that the north-south imaging scan rate of some GEOs can be slowed or reversed. Therefore the feasibility of obtaining stereoscopic observations world wide from combinations of operational GEO and LEO satellites has been demonstrated. Stereoscopy from satellites has many advantages over infrared techniques for the observation of cloud structure because it depends only on basic geometric relationships. Digital remapping of GEO and LEO satellite images is imperative for precision stereo height measurement and high quality displays because of the curvature of the earth and the large angular separation of the

Saturn's outer satellite, Phoebe

NASA Technical Reports Server (NTRS)

1981-01-01

Voyager 2 took this photo of Saturn's outer satellite, Phoebe, on Sept. 4, 1981, from 2.2 million kilometers (1.36 million miles) away. The photo shows that Phoebe is about 200 kilometers (120 miles) in diameter, about twice the size of Earth-based measurements; and dark, with five percent reflectivity -- much darker than any other Saturnian satellite. That, and information from Earth-based observations, indicates Phoebe is almost certainly a captured asteroid, and did not form in the original Saturn nebula as Saturn's other satellites did. Phoebe is the only Saturnian satellite that does not always show the same face to Saturn: Its orbital period is 550 days. Its rotation period (length of day), determined from Voyager 2 observations, is nine to ten hours. Other ground-based observations that indicate that Phoebe is a captured asteroid: It orbits Saturn in the ecliptic plane (the plane in which Earth and most other planets orbit the Sun), rather than in Saturn's equatorial plane as the other Saturn satellites do. And Phoebe's orbit is retrograde -- in the direction opposite to that of the other satellites. Voyager is managed for NASA's Office of Space Science by the Jet Propulsion Laboratory.

On a more rigorous gravity field processing for future LL-SST type gravity satellite missions

NASA Astrophysics Data System (ADS)

Daras, I.; Pail, R.; Murböck, M.

2013-12-01

In order to meet the augmenting demands of the user community concerning accuracies of temporal gravity field models, future gravity missions of low-low satellite-to-satellite tracking (LL-SST) type are planned to carry more precise sensors than their precedents. A breakthrough is planned with the improved LL-SST measurement link, where the traditional K-band microwave instrument of 1μm accuracy will be complemented by an inter-satellite ranging instrument of several nm accuracy. This study focuses on investigations concerning the potential performance of the new sensors and their impact in gravity field solutions. The processing methods for gravity field recovery have to meet the new sensor standards and be able to take full advantage of the new accuracies that they provide. We use full-scale simulations in a realistic environment to investigate whether the standard processing techniques suffice to fully exploit the new sensors standards. We achieve that by performing full numerical closed-loop simulations based on the Integral Equation approach. In our simulation scheme, we simulate dynamic orbits in a conventional tracking analysis to compute pseudo inter-satellite ranges or range-rates that serve as observables. Each part of the processing is validated separately with special emphasis on numerical errors and their impact in gravity field solutions. We demonstrate that processing with standard precision may be a limiting factor for taking full advantage of new generation sensors that future satellite missions will carry. Therefore we have created versions of our simulator with enhanced processing precision with primarily aim to minimize round-off system errors. Results using the enhanced precision show a big reduction of system errors that were present at the standard precision processing even for the error-free scenario, and reveal the improvements the new sensors will bring into the gravity field solutions. As a next step, we analyze the contribution of

The 26th Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

NASA Technical Reports Server (NTRS)

Sydnor, Richard (Editor)

1995-01-01

This document is a compilation of technical papers presented at the 26th Annual PTTI Applications and Planning Meeting. Papers are in the following categories: (1) Recent developments in rubidium, cesium, and hydrogen-based frequency standards, and in cryogenic and trapped-ion technology; (2) International and transnational applications of Precise Time and Time Interval technology with emphasis on satellite laser tracking, GLONASS timing, intercomparison of national time scales and international telecommunications; (3) Applications of Precise Time and Time Interval technology to the telecommunications, power distribution, platform positioning, and geophysical survey industries; (4) Applications of PTTI technology to evolving military communications and navigation systems; and (5) Dissemination of precise time and frequency by means of GPS, GLONASS, MILSTAR, LORAN, and synchronous communications satellites.

Cost Consideration for Future Communications Satellite

NASA Astrophysics Data System (ADS)

Iida, Takashi

2002-01-01

This paper discusses the cost driving factors of the future communications satellite rather than discussing its cost itself directly, in terms of development period of time, services, and R&D by government. In the first, a period of time for development of a communications system is discussed in comparison of satellite communications system with a terrestrial communications system. Generally speaking, the terrestrial communications system is developed in a short period. Especially, the recent network related IT technology changes very rapidly, like so-called as "Dog Year". On the other hand, it takes a long time, more than several years, to develop a satellite communications system. This paper will discuss this time period of development is how to influence the system realization in various cases. In the second, the service related cost is discussed. First, a mobile communications satellite system is considered as an example. The tremendous penetration speed of the terrestrial cellular phones prevents from the success of the mobile satellite communications system. The success of the mobile satellite communications system depends on how early and user friendly to develop its user terminals. Second, the broadcasting service is described as a successful example. It is described that the satellite broadcasting has a very competitive advantage to the terrestrial broadcasting service from the cost point of view. Finally, the cost of the technology R&D for the future communication satellite by the government is discussed. A model of the future communications satellite for next 30 years has been proposed(1)(2). As an example, this paper estimates the satellite cost of the 60 Gbps range of capacity which is called as 1.5G satellite, where the capacity of the second generation Internet satellite (2G) is 50-500 Gbps per satellite. In the paper, the R&D plan of the future communications satellite will be discussed as a next R&D project to the first generation Internet

NPP Satellite Launch

NASA Image and Video Library

2011-10-28

NASA Deputy Administrator Lori Garver, left, watches the launch of the National Polar-orbiting Operational Environmental Satellite System Preparatory Project (NPP) at the National Oceanic and Atmospheric Administration (NOAA) Satellite Operations Center on Friday, Oct. 28, 2011 in Suitland, Md. U.S Congresswoman Donna Edwards, D-Md., is seen next to Garver. NPP is a joint venture between NASA and NOAA, and is the nation's newest Earth-observing satellite, which will provide data on climate change science, allow for accurate weather forecasts and advance warning for severe weather. NPP was launched from Vandenberg Air Force Base in California. Photo Credit: (NASA/Carla Cioffi)

Timation 3 satellite. [artificial satellite for navigation, space radiation, and time transfer applications

NASA Technical Reports Server (NTRS)

Bartholomew, C. A.

1972-01-01

The characteristics of the Timation 3 satellite are discussed. A diagram of the basic structure is provide to show the solar panels, navigation and telemetry antennas, gravity gradient booms, and solar cell experiments. The specific application of the satellite for time management or time transfer for navigation purposes is reported. Various measurements and experiments conducted by the satellite are described.

Design and performance evaluation of the imaging payload for a remote sensing satellite

NASA Astrophysics Data System (ADS)

Abolghasemi, Mojtaba; Abbasi-Moghadam, Dariush

2012-11-01

In this paper an analysis method and corresponding analytical tools for design of the experimental imaging payload (IMPL) of a remote sensing satellite (SINA-1) are presented. We begin with top-level customer system performance requirements and constraints and derive the critical system and component parameters, then analyze imaging payload performance until a preliminary design that meets customer requirements. We consider system parameters and components composing the image chain for imaging payload system which includes aperture, focal length, field of view, image plane dimensions, pixel dimensions, detection quantum efficiency, and optical filter requirements. The performance analysis is accomplished by calculating the imaging payload's SNR (signal-to-noise ratio), and imaging resolution. The noise components include photon noise due to signal scene and atmospheric background, cold shield, out-of-band optical filter leakage and electronic noise. System resolution is simulated through cascaded modulation transfer functions (MTFs) and includes effects due to optics, image sampling, and system motion. Calculations results for the SINA-1 satellite are also presented.

Spectrum and power allocation in cognitive multi-beam satellite communications with flexible satellite payloads

NASA Astrophysics Data System (ADS)

Liu, Zhihui; Wang, Haitao; Dong, Tao; Yin, Jie; Zhang, Tingting; Guo, Hui; Li, Dequan

2018-02-01

In this paper, the cognitive multi-beam satellite system, i.e., two satellite networks coexist through underlay spectrum sharing, is studied, and the power and spectrum allocation method is employed for interference control and throughput maximization. Specifically, the multi-beam satellite with flexible payload reuses the authorized spectrum of the primary satellite, adjusting its transmission band as well as power for each beam to limit its interference on the primary satellite below the prescribed threshold and maximize its own achievable rate. This power and spectrum allocation problem is formulated as a mixed nonconvex programming. For effective solving, we first introduce the concept of signal to leakage plus noise ratio (SLNR) to decouple multiple transmit power variables in the both objective and constraint, and then propose a heuristic algorithm to assign spectrum sub-bands. After that, a stepwise plus slice-wise algorithm is proposed to implement the discrete power allocation. Finally, simulation results show that adopting cognitive technology can improve spectrum efficiency of the satellite communication.

Interim Service ISDN Satellite (ISIS) hardware experiment development for advanced ISDN satellite designs and experiments

NASA Technical Reports Server (NTRS)

Pepin, Gerard R.

1992-01-01

The Interim Service Integrated Service Digital Network (ISDN) Satellite (ISIS) Hardware Experiment Development for Advanced Satellite Designs describes the development of the ISDN Satellite Terminal Adapter (ISTA) capable of translating ISDN protocol traffic into Time Division Multiple Access (TDMA) signals for use by a communications satellite. The ISTA connects the Type 1 Network Termination (NT1) via the U-interface on the line termination side of the CPE to the RS-499 interface for satellite uplink. The same ISTA converts in the opposite direction the RS-499 to U-interface data with a simple switch setting.

Interim Service ISDN Satellite (ISIS) hardware experiment design for advanced ISDN satellite design and experiments

NASA Technical Reports Server (NTRS)

Pepin, Gerard R.

1992-01-01

The Interim Service Integrated Services Digital Network (ISDN) Satellite (ISIS) Hardware Experiment Design for Advanced Satellite Designs describes the design of the ISDN Satellite Terminal Adapter (ISTA) capable of translating ISDN protocol traffic into time division multiple access (TDMA) signals for use by a communications satellite. The ISTA connects the Type 1 Network Termination (NT1) via the U-interface on the line termination side of the CPE to the V.35 interface for satellite uplink. The same ISTA converts in the opposite direction the V.35 to U-interface data with a simple switch setting.

Individual Global Navigation Satellite Systems in the Space Service Volume

NASA Technical Reports Server (NTRS)

Force, Dale A.

2015-01-01

Besides providing position, navigation, and timing (PNT) to terrestrial users, GPS is currently used to provide for precision orbit determination, precise time synchronization, real-time spacecraft navigation, and three-axis control of Earth orbiting satellites. With additional Global Navigation Satellite Systems (GNSS) coming into service (GLONASS, Beidou, and Galileo), it will be possible to provide these services by using other GNSS constellations. The paper, "GPS in the Space Service Volume," presented at the ION GNSS 19th International Technical Meeting in 2006 (Ref. 1), defined the Space Service Volume, and analyzed the performance of GPS out to 70,000 km. This paper will report a similar analysis of the performance of each of the additional GNSS and compare them with GPS alone. The Space Service Volume, defined as the volume between 3,000 km altitude and geosynchronous altitude, as compared with the Terrestrial Service Volume between the surface and 3,000 km. In the Terrestrial Service Volume, GNSS performance will be similar to performance on the Earth's surface. The GPS system has established signal requirements for the Space Service Volume. A separate paper presented at the conference covers the use of multiple GNSS in the Space Service Volume.

Using Deep Learning Model for Meteorological Satellite Cloud Image Prediction

NASA Astrophysics Data System (ADS)

Su, X.

2017-12-01

A satellite cloud image contains much weather information such as precipitation information. Short-time cloud movement forecast is important for precipitation forecast and is the primary means for typhoon monitoring. The traditional methods are mostly using the cloud feature matching and linear extrapolation to predict the cloud movement, which makes that the nonstationary process such as inversion and deformation during the movement of the cloud is basically not considered. It is still a hard task to predict cloud movement timely and correctly. As deep learning model could perform well in learning spatiotemporal features, to meet this challenge, we could regard cloud image prediction as a spatiotemporal sequence forecasting problem and introduce deep learning model to solve this problem. In this research, we use a variant of Gated-Recurrent-Unit(GRU) that has convolutional structures to deal with spatiotemporal features and build an end-to-end model to solve this forecast problem. In this model, both the input and output are spatiotemporal sequences. Compared to Convolutional LSTM(ConvLSTM) model, this model has lower amount of parameters. We imply this model on GOES satellite data and the model perform well.

Endangered species: where leatherback turtles meet fisheries.

PubMed

Ferraroli, Sandra; Georges, Jean-Yves; Gaspar, Philippe; Le Maho, Yvon

2004-06-03

The dramatic worldwide decline in populations of the leatherback turtle (Dermochelys coriacea) is largely due to the high mortality associated with their interaction with fisheries, so a reduction of this overlap is critical to their survival. The discovery of narrow migration corridors used by the leatherbacks in the Pacific Ocean raised the possibility of protecting the turtles by restricting fishing in these key areas. Here we use satellite tracking to show that there is no equivalent of these corridors in the North Atlantic Ocean, because the turtles disperse actively over the whole area. But we are able to identify a few 'hot spots' where leatherbacks meet fisheries and where conservation efforts should be focused.

The Skeletal Muscle Satellite Cell

PubMed Central

2011-01-01

The skeletal muscle satellite cell was first described and named based on its anatomic location between the myofiber plasma and basement membranes. In 1961, two independent studies by Alexander Mauro and Bernard Katz provided the first electron microscopic descriptions of satellite cells in frog and rat muscles. These cells were soon detected in other vertebrates and acquired candidacy as the source of myogenic cells needed for myofiber growth and repair throughout life. Cultures of isolated myofibers and, subsequently, transplantation of single myofibers demonstrated that satellite cells were myogenic progenitors. More recently, satellite cells were redefined as myogenic stem cells given their ability to self-renew in addition to producing differentiated progeny. Identification of distinctively expressed molecular markers, in particular Pax7, has facilitated detection of satellite cells using light microscopy. Notwithstanding the remarkable progress made since the discovery of satellite cells, researchers have looked for alternative cells with myogenic capacity that can potentially be used for whole body cell-based therapy of skeletal muscle. Yet, new studies show that inducible ablation of satellite cells in adult muscle impairs myofiber regeneration. Thus, on the 50th anniversary since its discovery, the satellite cell’s indispensable role in muscle repair has been reaffirmed. PMID:22147605

Communication Technology Satellite Portable Terminal

NASA Image and Video Library

1977-03-21

This vehicle served as a mobile terminal for the Communications Technology Satellite. The Communications Technology Satellite was an experimental communications satellite launched in January 1976 by the National Aeronautics and Space Administration (NASA) and the Canadian Department of Communications. The satellite operated in a new frequency band reserved for broadcast satellites with transmitting power levels that were 10 to 20 times higher than those of contemporary satellites. Throughout 1977 and 1978 NASA allowed qualified groups to utilize the satellite from one of the three ground-based transmission centers. NASA’s Lewis Research Center in Cleveland, Ohio was NASA’s lead center on the project. Lewis was responsible for the control and coordination of all US experiments on the satellite. The center housed the satellite’s main control center which included eight parabolic reflector antennae ranging from 2 to 15 feet in diameter. Many of the satellite’s components had been tested in simulated space conditions at Lewis. The Lewis-designed vehicle seen here served as a field unit for transmitting and receiving wideband signals and narrowband voice. The vehicle permitted live television interviews, recording equipment, and cameras. An 8-foot diameter parabolic reflector was mounted on the roof. The interior of the vehicle had workstations, monitors, transmitting equipment, and a lounge area.

Emerging technologies for communication satellite payloads

NASA Astrophysics Data System (ADS)

Yüceer, Mehmet

2012-04-01

Recent developments in payload designs will allow more flexible and efficient use of telecommunication satellites. Important modifications in repeater designs, antenna structures and spectrum policies open up exciting opportunities for GEO satellites to support a variety of emerging applications, ranging from telemedicine to real-time data transfer between LEO satellite and ground station. This study gives information about the emerging technologies in the design of communication satellites' transceiver subsystem and demonstrates the feasibility of using fiber optic links for the local oscillator distribution in future satellite payloads together with the optical inter-satellite link.

Studying the Surfaces of the Icy Galilean Satellites With JIMO

NASA Astrophysics Data System (ADS)

Prockter, L.; Schenk, P.; Pappalardo, R.

2003-12-01

The Geology subgroup of the Jupiter Icy Moons Orbiter (JIMO) Science Definition Team (SDT) has been working with colleagues within the planetary science community to determine the key outstanding science goals that could be met by the JIMO mission. Geological studies of the Galilean satellites will benefit from the spacecraft's long orbital periods around each satellite, lasting from one to several months. This mission plan allows us to select the optimal viewing conditions to complete global compositional and morphologic mapping at high resolution, and to target geologic features of key scientific interest at very high resolution. Community input to this planning process suggests two major science objectives, along with corresponding measurements proposed to meet them. Objective 1: Determine the origins of surface features and their implications for geological history and evolution. This encompasses investigations of magmatism (intrusion, extrusion, and diapirism), tectonism (isostatic compensation, and styles of faulting, flexure and folding), impact cratering (morphology and distribution), and gradation (erosion and deposition) processes (impact gardening, sputtering, mass wasting and frosts). Suggested measurements to meet this goal include (1) two dimensional global topographic mapping sufficient to discriminate features at a spatial scale of 10 m, and with better than or equal to 1 m relative vertical accuracy, (2) nested images of selected target areas at a range of resolutions down to the submeter pixel scale, (3) global (albedo) mapping at better than or equal to 10 m/pixel, and (4) multispectral global mapping in at least 3 colors at better than or equal to 100 m/pixel, with some subsets at better than 30 m/pixel. Objective 2. Identify and characterize potential landing sites for future missions. A primary component to the success of future landed missions is full characterization of potential sites in terms of their relative age, geological interest, and

JEMRMS Small Satellite Deployment Observation

NASA Image and Video Library

2012-10-04

ISS033-E-009315 (4 Oct. 2012) --- Several tiny satellites are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module’s robotic arm on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment. A blue and white part of Earth provides the backdrop for the scene.

The AMSC mobile satellite system

NASA Technical Reports Server (NTRS)

Agnew, Carson E.; Bhagat, Jai; Hopper, Edwin A.; Kiesling, John D.; Exner, Michael L.; Melillo, Lawrence; Noreen, Gary K.; Parrott, Billy J.

1988-01-01

The American Mobile Satellite Consortium (AMSC) Mobile Satellite Service (MSS) system is described. AMSC will use three multi-beam satellites to provide L-band MSS coverage to the United States, Canada and Mexico. The AMSC MSS system will have several noteworthy features, including a priority assignment processor that will ensure preemptive access to emergency services, a flexible SCPC channel scheme that will support a wide diversity of services, enlarged system capacity through frequency and orbit reuse, and high effective satellite transmitted power. Each AMSC satellite will make use of 14 MHz (bi-directional) of L-band spectrum. The Ku-band will be used for feeder links.

Collision Avoidance: Coordination of Predicted Conjunctions between NASA Satellites and Satellites of other Countries

NASA Astrophysics Data System (ADS)

Kelly, A.; Watson, W.

2014-09-01

This paper describes one of the challenges facing the flight operations teams of the International Earth Observing constellation satellites at the 705 km orbit, including NASAs satellites. The NASA Earth Science Mission Operations (ESMO) Project has been dealing with predicted conjunctions (close approach) between operational/non-operational space objects and the satellites in the International Earth observing constellations for several years. Constellation satellites include: NASAs Earth Observing System (EOS) Terra, Aqua, and Aura, CloudSat, the joint NASA/CNES CALIPSO mission, Earth Observing 1 (EO-1), the Japan Aerospace and Exploration Agency (JAXA) Global Change Observation Mission-Water 1 (GCOM-W1) mission, the United States Geological Survey (USGS) Landsat 7 and Landsat 8, and until 2013, Argentinas SAC-C mission and the CNES PARASOL mission. The NASA Conjunction Analysis and Risk Assessment (CARA) team provides daily reports to the ESMO Project regarding any high interest close approach events (HIEs) involving the constellation satellites. The daily CARA reports provide risk assessment results that help the operations teams to determine if there is a need to perform a risk mitigation action. If the conjuncting space object is an operational satellite that is capable of maneuvering, the affected satellite team needs to coordinate their action plan with the owner operator of the conjuncting satellite. It is absolutely critical for the two teams to communicate as soon as possible. The goal is to minimize the collision risk; this can happen if both satellite operators do not coordinate their maneuver plans. The constellation teams have established guidelines for coordinating HIEs. This coordination process has worked successfully for several years for satellites that are operated by other organizations in the United States and by NASAs international partners, all with whom NASA has a cooperative agreement. However, the situation is different for HIEs with

Utilization of photovoltaic for broadband satellite communications in rural area of Thailand

NASA Astrophysics Data System (ADS)

Jinayim, Theerawut; Mungkung, Narong; Kasayapanand, Nat

2013-06-01

Electricity, Information and Communication Technologies (ICTs) are very important not only in urban areas but also in rural areas. To provide ICTs service in rural areas, sources of electricity and communication infrastructures must be implemented. Electricity is a major condition due to the fact that all electronic devices needed it in order to power on, so that it is impossible to operate any forms of ICTs in areas where the main national grid line is unavailable. Almost rural areas of Thailand where the main national grid line is unavailable have very good sunlight intensity. Photovoltaic is the most effective renewable energy technologies in those areas for meeting electricity needed in areas that are not connected to the main national grid line. In this paper, the efficiency utilization of photovoltaic as source of electricity for broadband satellite communication systems as well as social and economic impact and quality of life of people in rural areas of Thailand are presented. The results show that most rural communities would be able to universally access to the basic telecommunications services such as internet access and public telephone via satellite communication systems. However, in some field case study, broadband internet access via satellite communication may be unnecessary for some rural communities and the most exactly rural communities needed are electricity for household usage and battery charger.

A mission-oriented orbit design method of remote sensing satellite for region monitoring mission based on evolutionary algorithm

NASA Astrophysics Data System (ADS)

Shen, Xin; Zhang, Jing; Yao, Huang

2015-12-01

Remote sensing satellites play an increasingly prominent role in environmental monitoring and disaster rescue. Taking advantage of almost the same sunshine condition to same place and global coverage, most of these satellites are operated on the sun-synchronous orbit. However, it brings some problems inevitably, the most significant one is that the temporal resolution of sun-synchronous orbit satellite can't satisfy the demand of specific region monitoring mission. To overcome the disadvantages, two methods are exploited: the first one is to build satellite constellation which contains multiple sunsynchronous satellites, just like the CHARTER mechanism has done; the second is to design non-predetermined orbit based on the concrete mission demand. An effective method for remote sensing satellite orbit design based on multiobjective evolution algorithm is presented in this paper. Orbit design problem is converted into a multi-objective optimization problem, and a fast and elitist multi-objective genetic algorithm is utilized to solve this problem. Firstly, the demand of the mission is transformed into multiple objective functions, and the six orbit elements of the satellite are taken as genes in design space, then a simulate evolution process is performed. An optimal resolution can be obtained after specified generation via evolution operation (selection, crossover, and mutation). To examine validity of the proposed method, a case study is introduced: Orbit design of an optical satellite for regional disaster monitoring, the mission demand include both minimizing the average revisit time internal of two objectives. The simulation result shows that the solution for this mission obtained by our method meet the demand the users' demand. We can draw a conclusion that the method presented in this paper is efficient for remote sensing orbit design.

Small Satellite Propulsion Options

NASA Technical Reports Server (NTRS)

Myers, Roger M.; Oleson, Steven R.; Curran, Francis M.; Schneider, Steven J.

1994-01-01

Advanced chemical and low power electric propulsion offer attractive options for small satellite propulsion. Applications include orbit raising, orbit maintenance, attitude control, repositioning, and deorbit of both Earth-space and planetary spacecraft. Potential propulsion technologies for these functions include high pressure Ir/Re bipropellant engines, very low power arcjets, Hall thrusters, and pulsed plasma thrusters, all of which have been shown to operate in manners consistent with currently planned small satellites. Mission analyses show that insertion of advanced propulsion technologies enables and/or greatly enhances many planned small satellite missions. Examples of commercial, DoD, and NASA missions are provided to illustrate the potential benefits of using advanced propulsion options on small satellites.

Weather, land satellite sale

NASA Astrophysics Data System (ADS)

Richman, Barbara T.

President Ronald Reagan announced on March 8 plans to sell to private industry the nation's land and meteorological remote-sensing satellites, including the responsibility for any future ocean-observing systems. According to the plan, the private firm successful in its bid to buy the five satellites would sell back to the government the data received by the satellites. The Reagan administration says the sale will save money and will put activities appropriate for commercial ventures into the commercial sector. Response to the announcement from scientists and congressmen has been anything but dulcet; one senator, in fact, charges that the Commerce Department and the corporation most likely to purchase the satellites are engaged in a ‘sweetheart deal.’

Two-way satellite time transfer: Overview and recent developments

NASA Technical Reports Server (NTRS)

Dejong, Gerrit

1994-01-01

The experiment using small earth stations for transatlantic two-way satellite time transfer between the USA and Germany has had its 10th anniversary this year. Pseudo-random noise coded time signals were phase modulated and demodulated at each station using a modem. Recently, during the last two weeks of Aug. 1993, six European time laboratories have used the INTELSAT 307E satellite for line-up tests and preliminary time transfer sessions using the same type of MITREX modem. The need for a uniform format for the exchange of data was felt heavily after these sessions. This problem was foreseen and addressed in international working parties. During Apr. 1993, in Task Group 7/2 of the ITU Radiocommunication Sector, a very intense discussion has taken place about what procedure should be recommended for TWSTFT and what items the header and data lines of the resulting data fields should contain. A difficulty is that two different methods of calibration of the earth station delays exist which result in different sets of delay data to be exchanged. Further study and discussions are necessary. Also, a meeting of the CCDS Working Group on TWSTFT addressed this in Oct. 1993. The outcome of the discussions and the prospect for future developments are presented.

Mobile satellite regulation in the United States

NASA Technical Reports Server (NTRS)

Levin, Lon C.; Sonnenfeldt, Walter H.

1990-01-01

During the last decade, the U.S. FCC has developed the regulatory structure for the provision of mobile services via satellite. In May 1989, the FCC awarded American Mobile Satellite Corporation (AMSC) a license to provide the full range of domestic mobile satellite services in the U.S. At that time, the FCC reaffirmed the U.S. mobile satellite industry structure and spectrum allocations that had been adopted previously. Also in May 1989, the FCC authorized the Communications Satellite Corporation (COMSAT), the U.S. Signatory to Inmarsat, to provide international aeronautical satellite service via the Inmarsat system. Earlier in 1989, the FCC permitted the use of Ku-band satellites to provide messaging and tracking services. In the mid-1980's, the FCC established the Radiodetermination Satellite Service and awarded licenses. Among the mobile satellite matters currently facing the FCC are whether additional spectrum should be allocated for domestic 'generic' mobile satellite services, the regulatory structure for the provision of mobile satellite service on an interim basis before AMSC launches its dedicated satellites, and whether to authorize a low earth orbit satellite system to provide mobile data service.

Mobile satellite service for Canada

NASA Technical Reports Server (NTRS)

Sward, David

1988-01-01

The Mobile Satellite (MSAT) system and a special program designed to provide interim mobile satellite services (IMSS) during the construction phase of MSAT are described. A mobile satellite system is a key element in extending voice and and data telecommunications to all Canadians.

Broadcast satellite service: The international dimension

NASA Technical Reports Server (NTRS)

Samara, Noah

1991-01-01

The dawn of the 1990's has witnessed the birth of a new satellite service - satellite sound broadcasting. This new service is characterized by digital transmission at data rates up to 256 kb/s from satellites in geostationary orbit to small, low-cost, mobile and portable receivers. The satellite sound broadcasting service is a logical step beyond navigation satellite service, such as that provided by the GPS Navstar system. The mass market appeal of satellite sound broadcasting in the area of lightsat technology and low-cost digital radios has greatly facilitated the financing of this type of space service.

Broadcast satellite service: The international dimension

NASA Astrophysics Data System (ADS)

Samara, Noah

1991-09-01

The dawn of the 1990's has witnessed the birth of a new satellite service - satellite sound broadcasting. This new service is characterized by digital transmission at data rates up to 256 kb/s from satellites in geostationary orbit to small, low-cost, mobile and portable receivers. The satellite sound broadcasting service is a logical step beyond navigation satellite service, such as that provided by the GPS Navstar system. The mass market appeal of satellite sound broadcasting in the area of lightsat technology and low-cost digital radios has greatly facilitated the financing of this type of space service.

Activities of Canadian Satellite Communications, Inc.

NASA Astrophysics Data System (ADS)

1992-12-01

Canadian Satellite Communications (Cancom) has as its core business the provision of television and radio signals to cable systems in Canada, with the objective of making affordable broadcast signals available to remote and/or small communities. Cancom also provides direct-to-home services to backyard receiving dishes, as well as satellite digital data business communications services, satellite business television, and satellite network services. Its business communication services range from satellite links for big-city businesses with small branch operations located far from major centers, to a mobile messaging and tracking system for the trucking industry. Revenues in 1992 totalled $48,212,000 and net income was just over $7 million. Cancom bought 10 percent interest in Leosat Corp. of Washington, DC, who are seeking approval to operate a position locator network from low-orbit satellites. Cancom has also become a partner in SovCan Star Satellite Communications Inc., which will build an international satellite system in partnership with Russia. The first satellite in this east-west business network will be placed in a Russian orbital slot over the Atlantic by 1996, and a second satellite will follow for the Pacific region. This annual report of Cancom's activities for 1992 includes financial statements and a six year financial review.

Satellite applications to electric-utility communications needs. [land mobile satellite service

NASA Technical Reports Server (NTRS)

Horstein, M.; Barnett, R.

1981-01-01

Significant changes in the Nation's electric power systems are expected to result from the integration of new technology, possible during the next decade. Digital communications for monitor and control, exclusive of protective relaying, are expected to double or triple current traffic. A nationwide estimate of 13 Mb/s traffic is projected. Of this total, 8 Mb/s is attributed to the bulk-power system as it is now being operated (4 Mb/s). This traffic could be accommodated by current communications satellites using 3- to 4.5-m-diameter ground terminals costing $35,000 to $70,000 each. The remaining 5-Mb/s traffic is attributed to new technology concepts integrated into the distribution system. Such traffic is not compatible with current satellite technology because it requires small, low-cost ground terminals. Therefore, a high effective isotropic radiated power satellite, such as the one being planned by NASA for the Land Mobile Satellite Service, is required.

NPP Satellite Launch

NASA Image and Video Library

2011-10-28

Dr. Kathy Sullivan, center, Deputy Administrator of the National Oceanic and Atmospheric Administration (NOAA) and former NASA astronaut is interviewed by a local television network at NOAA's Satellite Operations Facility in Suitland, Md. after the successful launch of the National Polar-orbiting Operational Environmental Satellite System Preparatory Project (NPP) on Friday, Oct. 28, 2011. NPP is a joint venture between NASA and NOAA, and is the nation's newest Earth-observing satellite, which will provide data on climate change science, allow for accurate weather forecasts and advance warning for severe weather. NPP was launched from Vandenberg Air Force Base in California. Photo Credit: (NASA/Carla Cioffi)

Optimizing communication satellites payload configuration with exact approaches

NASA Astrophysics Data System (ADS)

Stathakis, Apostolos; Danoy, Grégoire; Bouvry, Pascal; Talbi, El-Ghazali; Morelli, Gianluigi

2015-12-01

The satellite communications market is competitive and rapidly evolving. The payload, which is in charge of applying frequency conversion and amplification to the signals received from Earth before their retransmission, is made of various components. These include reconfigurable switches that permit the re-routing of signals based on market demand or because of some hardware failure. In order to meet modern requirements, the size and the complexity of current communication payloads are increasing significantly. Consequently, the optimal payload configuration, which was previously done manually by the engineers with the use of computerized schematics, is now becoming a difficult and time consuming task. Efficient optimization techniques are therefore required to find the optimal set(s) of switch positions to optimize some operational objective(s). In order to tackle this challenging problem for the satellite industry, this work proposes two Integer Linear Programming (ILP) models. The first one is single-objective and focuses on the minimization of the length of the longest channel path, while the second one is bi-objective and additionally aims at minimizing the number of switch changes in the payload switch matrix. Experiments are conducted on a large set of instances of realistic payload sizes using the CPLEX® solver and two well-known exact multi-objective algorithms. Numerical results demonstrate the efficiency and limitations of the ILP approach on this real-world problem.

Research on the system performance evaluation of minimum-shift keying in uplink ground-to-satellite with gamma-gamma distribution

NASA Astrophysics Data System (ADS)

Wang, Yi; Zhang, Ao; Ma, Jing

2017-07-01

Minimum-shift keying (MSK) has the advantages of constant envelope, continuous phase, and high spectral efficiency, and it is applied in radio communication and optical fiber communication. MSK modulation of coherent detection is proposed in the ground-to-satellite laser communication system; in addition, considering the inherent noise of uplink, such as intensity scintillation and beam wander, the communication performance of the MSK modulation system with coherent detection is studied in the uplink ground-to-satellite laser. Based on the gamma-gamma channel model, the closed form of bit error rate (BER) of MSK modulation with coherent detection is derived. In weak, medium, and strong turbulence, the BER performance of the MSK modulation system is simulated and analyzed. To meet the requirements of the ground-to-satellite coherent MSK system to optimize the parameters and configuration of the transmitter and receiver, the influence of the beam divergence angle, the zenith angle, the transmitter beam radius, and the receiver diameter are studied.

Security Concepts for Satellite Links

NASA Astrophysics Data System (ADS)

Tobehn, C.; Penné, B.; Rathje, R.; Weigl, A.; Gorecki, Ch.; Michalik, H.

2008-08-01

The high costs to develop, launch and maintain a satellite network makes protecting the assets imperative. Attacks may be passive such as eavesdropping on the payload data. More serious threat are active attacks that try to gain control of the satellite, which may lead to the total lost of the satellite asset. To counter these threats, new satellite and ground systems are using cryptographic technologies to provide a range of services: confidentiality, entity & message authentication, and data integrity. Additionally, key management cryptographic services are required to support these services. This paper describes the key points of current satellite control and operations, that are authentication of the access to the satellite TMTC link and encryption of security relevant TM/TC data. For payload data management the key points are multi-user ground station access and high data rates both requiring frequent updates and uploads of keys with the corresponding key management methods. For secure satellite management authentication & key negotiation algorithms as HMAC-RIPEMD160, EC- DSA and EC-DH are used. Encryption of data uses algorithms as IDEA, AES, Triple-DES, or other. A channel coding and encryption unit for payload data provides download data rates up to Nx250 Mbps. The presented concepts are based on our experience and heritage of the security systems for all German MOD satellite projects (SATCOMBw2, SAR-Lupe multi- satellite system and German-French SAR-Lupe-Helios- II systems inter-operability) as well as for further international (KOMPSAT-II Payload data link system) and ESA activities (TMTC security and GMES).

Satellites in Schools.

ERIC Educational Resources Information Center

Underwood, C. I.; And Others

1987-01-01

Discusses the use of satellite data in physics classrooms. Describes the apparatus that can be used to collect and analyze data. Provides examples of how telemetry data transmitted by the satellite UoSAT-2 can be used not only in teaching physics, but also in geography, mathematics, and information technology. (TW)

Meeting report: Metastasis Research Society-Chinese Tumor Metastasis Society joint conference on metastasis.

PubMed

Bankaitis, Katherine; Borriello, Lucia; Cox, Thomas; Lynch, Conor; Zijlstra, Andries; Fingleton, Barbara; Gužvić, Miodrag; Anderson, Robin; Neman, Josh

2017-04-01

During September 16th-20th 2016, metastasis experts from around the world convened for the 16th Biennial Congress of the Metastasis Research Society and 12th National Congress of the Chinese Tumor Metastasis Society in Chengdu, China to share most current data covering basic, translational, and clinical metastasis research. Presentations of the more than 40 invited speakers of the main congress and presentations from the associated Young Investigator Satellite Meeting are summarized in this report by session topic. The congress program also included three concurrent short talk sessions, an advocacy forum with Chinese and American metastatic patient advocates, a 'Meet the Professors Roundtable' session for young investigators, and a 'Meet the Editors' session with editors from Cancer Cell and Nature Cell Biology. The goal of integrating expertise and exchanging the latest findings, ideas, and practices in cancer metastasis research was achieved magnificently, thanks to the excellent contributions of many leaders in the field.

JPSS Preparations at the Satellite Proving Ground for Marine, Precipitation, and Satellite Analysis

NASA Astrophysics Data System (ADS)

Folmer, M. J.; Berndt, E.; Clark, J.; Orrison, A.; Kibler, J.; Sienkiewicz, J. M.; Nelson, J. A., Jr.; Goldberg, M.

2016-12-01

The National Oceanic and Atmospheric Administration (NOAA) Satellite Proving Ground (PG) for Marine, Precipitation, and Satellite Analysis (MPS) has been demonstrating and evaluating Suomi National Polar-orbiting Partnership (S-NPP) products along with other polar-orbiting satellite platforms in preparation for the Joint Polar Satellite System - 1 (JPSS-1) launch in March 2017. The first S-NPP imagery was made available to the MPS PG during the evolution of Hurricane Sandy in October 2012 and has since been popular in operations. Since this event the MPS PG Satellite Liaison has been working with forecasters on ways to integrate single-channel and multispectral imagery from the Visible Infrared Imaging Radiometer Suite (VIIRS), the Moderate Resolution Imaging Spectroradiometer (MODIS), and the Advanced Very High Resolution Radiometer (AVHRR)into operations to complement numerical weather prediction and geostationary satellite savvy National Weather Service (NWS) National Centers. Additional unique products have been introduced to operations to address specific forecast challenges, including the Cooperative Institute for Research in the Atmosphere (CIRA) Layered Precipitable Water, the National Environmental Satellite, Data, and Information Service (NESDIS) Snowfall Rate product, NOAA Unique Combined Atmospheric Processing System (NUCAPS) Soundings, ozone products from the Atmospheric Infrared Sounder (AIRS), Cross-track Infrared Sounder/Advanced Technology Microwave Sounder (CrIS/ATMS), and Infrared Atmospheric Sounding Interferometer (IASI). In addition, new satellite domains have been created to provide forecasters at the NWS Ocean Prediction Center and Weather Prediction Center with better quality imagery at high latitudes. This has led to research projects that are addressing forecast challenges such as tropical to extratropical transition and explosive cyclogenesis. This presentation will provide examples of how the MPS PG has been introducing and integrating

Impact of multiconstellation satellite signal reception on performance of satellite-based navigation under adverse ionospheric conditions

NASA Astrophysics Data System (ADS)

Paul, Ashik; Paul, Krishnendu Sekhar; Das, Aditi

2017-03-01

Application of multiconstellation satellites to address the issue of satellite signal outages during periods of equatorial ionospheric scintillations could prove to be an effective tool for maintaining the performance of satellite-based communication and navigation without compromise in accuracy and integrity. A receiver capable of tracking GPS, Global Navigation Satellite System (GLONASS), and Galileo satellites is operational at the Institute of Radio Physics and Electronics, University of Calcutta, Calcutta, India, located near the northern crest of the equatorial ionization anomaly in the Indian longitude sector. The present paper shows increased availability of satellites combining GPS, GLONASS, and Galileo constellations from Calcutta compared to GPS-only scenario and estimates intense scintillation-free (S4 < 0.6) satellite vehicle look angles at different hours of the postsunset period 19:00-01:00 LT during March 2014. A representative case of 1 March 2014 is highlighted in the paper and overall statistics for March 2014 presented to indicate quantitative advantages in terms of scintillation-free satellite vehicle look angles that may be utilized for planning communication and navigation channel spatial distribution under adverse ionospheric conditions. The number of satellites tracked and receiver position deviations has been found to show a good correspondence with the occurrence of intense scintillations and poor user receiver-satellite link geometry. The ground projection of the 350 km subionospheric points corresponding to multiconstellation shows extended spatial coverage during periods of scintillations (0.2 < S4 < 0.6) compared to GPS.

Satellite services system overview

NASA Technical Reports Server (NTRS)

Rysavy, G.

1982-01-01

The benefits of a satellite services system and the basic needs of the Space Transportation System to have improved satellite service capability are identified. Specific required servicing equipment are discussed in terms of their technology development status and their operative functions. Concepts include maneuverable television systems, extravehicular maneuvering unit, orbiter exterior lighting, satellite holding and positioning aid, fluid transfer equipment, end effectors for the remote manipulator system, teleoperator maneuvering system, and hand and power tools.

Leveraging the NPS Femto Satellite for Alternative Satellite Communication Networks

DTIC Science & Technology

2017-09-01

the next-generation NPSFS. 14. SUBJECT TERMS space , Femto satellite, NPSFS, network, communication , Arduino, RockBlock, Iridium Modem 15. NUMBER...provides a proof of concept for using Naval Postgraduate School Femto Satellites (NPSFS) as an alternative communication space -based network. The...We need several physical and procedural elements to conduct communication through space and using the electromagnetic spectrum. 1. Power Any

Design Considerations for a Dedicated Gravity Recovery Satellite Mission Consisting of Two Pairs of Satellites

NASA Technical Reports Server (NTRS)

Wiese, D. N.; Nerem, R. S.; Lemoine, F. G.

2011-01-01

Future satellite missions dedicated to measuring time-variable gravity will need to address the concern of temporal aliasing errors; i.e., errors due to high-frequency mass variations. These errors have been shown to be a limiting error source for future missions with improved sensors. One method of reducing them is to fly multiple satellite pairs, thus increasing the sampling frequency of the mission. While one could imagine a system architecture consisting of dozens of satellite pairs, this paper explores the more economically feasible option of optimizing the orbits of two pairs of satellites. While the search space for this problem is infinite by nature, steps have been made to reduce it via proper assumptions regarding some parameters and a large number of numerical simulations exploring appropriate ranges for other parameters. A search space originally consisting of 15 variables is reduced to two variables with the utmost impact on mission performance: the repeat period of both pairs of satellites (shown to be near-optimal when they are equal to each other), as well as the inclination of one of the satellite pairs (the other pair is assumed to be in a polar orbit). To arrive at this conclusion, we assume circular orbits, repeat groundtracks for both pairs of satellites, a 100-km inter-satellite separation distance, and a minimum allowable operational satellite altitude of 290 km based on a projected 10-year mission lifetime. Given the scientific objectives of determining time-variable hydrology, ice mass variations, and ocean bottom pressure signals with higher spatial resolution, we find that an optimal architecture consists of a polar pair of satellites coupled with a pair inclined at 72deg, both in 13-day repeating orbits. This architecture provides a 67% reduction in error over one pair of satellites, in addition to reducing the longitudinal striping to such a level that minimal post-processing is required, permitting a substantial increase in the spatial

DEVELOPMENT OF IMPROVED TECHNIQUES FOR SATELLITE REMOTE SENSING OF CLOUDS AND RADIATION USING ARM DATA, FINAL REPORT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Minnis, Patrick

2013-06-28

During the period, March 1997 – February 2006, the Principal Investigator and his research team co-authored 47 peer-reviewed papers and presented, at least, 138 papers at conferences, meetings, and workshops that were supported either in whole or in part by this agreement. We developed a state-of-the-art satellite cloud processing system that generates cloud properties over the Atmospheric Radiation (ARM) surface sites and surrounding domains in near-real time and outputs the results on the world wide web in image and digital formats. When the products are quality controlled, they are sent to the ARM archive for further dissemination. These products andmore » raw satellite images can be accessed at http://cloudsgate2.larc.nasa.gov/cgi-bin/site/showdoc?docid=4&cmd=field-experiment-homepage&exp=ARM and are used by many in the ARM science community. The algorithms used in this system to generate cloud properties were validated and improved by the research conducted under this agreement. The team supported, at least, 11 ARM-related or supported field experiments by providing near-real time satellite imagery, cloud products, model results, and interactive analyses for mission planning, execution, and post-experiment scientific analyses. Comparisons of cloud properties derived from satellite, aircraft, and surface measurements were used to evaluate uncertainties in the cloud properties. Multiple-angle satellite retrievals were used to determine the influence of cloud structural and microphysical properties on the exiting radiation field.« less

Satellite Applications for Public Service: Project Summaries.

ERIC Educational Resources Information Center

Lauffer, Sandra; And Others

Summaries of 18 different projects involving the use of satellite communications are presented in this report, including PEACESAT Education and Communication Experiments, USP Network Satellite Communication Project, Project Satellite, Satellite Instructional Television Experiment (SITE), Appalachian Education Satellite Program, Alaska Education…

DS-CDMA satellite diversity reception for personal satellite communication: Downlink performance analysis

NASA Technical Reports Server (NTRS)

DeGaudenzi, Riccardo; Giannetti, Filippo

1995-01-01

The downlink of a satellite-mobile personal communication system employing power-controlled Direct Sequence Code Division Multiple Access (DS-CDMA) and exploiting satellite-diversity is analyzed and its performance compared with a more traditional communication system utilizing single satellite reception. The analytical model developed has been thoroughly validated by means of extensive Monte Carlo computer simulations. It is shown how the capacity gain provided by diversity reception shrinks considerably in the presence of increasing traffic or in the case of light shadowing conditions. Moreover, the quantitative results tend to indicate that to combat system capacity reduction due to intra-system interference, no more than two satellites shall be active over the same region. To achieve higher system capacity, differently from terrestrial cellular systems, Multi-User Detection (MUD) techniques are likely to be required in the mobile user terminal, thus considerably increasing its complexity.

Local gravity disturbance estimation from multiple-high-single-low satellite-to-satellite tracking

NASA Technical Reports Server (NTRS)

Jekeli, Christopher

1989-01-01

The idea of satellite-to-satellite tracking in the high-low mode has received renewed attention in light of the uncertain future of NASA's proposed low-low mission, Geopotential Research Mission (GRM). The principal disadvantage with a high-low system is the increased time interval required to obtain global coverage since the intersatellite visibility is often obscured by Earth. The U.S. Air Force has begun to investigate high-low satellite-to-satellite tracking between the Global Positioning System (GPS) of satellites (high component) and NASA's Space Transportation System (STS), the shuttle (low component). Because the GPS satellites form, or will form, a constellation enabling continuous three-dimensional tracking of a low-altitude orbiter, there will be no data gaps due to lack of intervisibility. Furthermore, all three components of the gravitation vector are estimable at altitude, a given grid of which gives a stronger estimate of gravity on Earth's surface than a similar grid of line-of-sight gravitation components. The proposed Air Force mission is STAGE (Shuttle-GPS Tracking for Anomalous Gravitation Estimation) and is designed for local gravity field determinations since the shuttle will likely not achieve polar orbits. The motivation for STAGE was the feasibility to obtain reasonable accuracies with absolutely minimal cost. Instead of simulating drag-free orbits, STAGE uses direct measurements of the nongravitational forces obtained by an inertial package onboard the shuttle. The sort of accuracies that would be achievable from STAGE vis-a-vis other satellite tracking missions such as GRM and European Space Agency's POPSAT-GRM are analyzed.

Encryption protection for communication satellites

NASA Astrophysics Data System (ADS)

Sood, D. R.; Hoernig, O. W., Jr.

In connection with the growing importance of the commercial communication satellite systems and the introduction of new technological developments, users and operators of these systems become increasingly concerned with aspects of security. The user community is concerned with maintaining confidentiality and integrity of the information being transmitted over the satellite links, while the satellite operators are concerned about the safety of their assets in space. In response to these concerns, the commercial satellite operators are now taking steps to protect the communication information and the satellites. Thus, communication information is being protected by end-to-end encryption of the customer communication traffic. Attention is given to the selection of the NBS DES algorithm, the command protection systems, and the communication protection systems.

Satellite Communications Industry

DTIC Science & Technology

1993-04-01

Ariane $loom SAJAC 1 Hughes Satellite Japan 06/94 $150m SAJAC 2 Hughes Satellite Japan -- (spare) $150m SatcomHl GE GE Americom /95 $50m SOLIDARIDAD ...1 Hughes SCT (Mexico) 11/93 Ariane $loom SOLIDARIDAD 2 Hughes SCT (Mexico) /94 $loom Superbird Al Loral Space Com Gp (Jap) 11/92 Ariane $175m

Satellite power system operations

NASA Technical Reports Server (NTRS)

Pugh, F. L.; Gordon, A. I.

1980-01-01

A projection of the electrical energy demands over the next 30 to 50 years, coupled with reasonable assessments of known or developable energy sources, indicates that a shortage of electrical energy will occur about the turn of the century. Recognizing the criticality of such a shortage, the Department of Energy is currently evaluating alternative power generation concepts. One of these candidate concepts is the Satellite Power System. The power levels considered during the evaluation of the various satellite systems have ranged from 5 to 10 GW. It is apparent that, with this power level, both the satellite and the rectenna must be very large and encompass a large number of complex operational system activities. Major elements of the Satellite Power System (SPS) consist of a power satellite placed in a geosynchronous equatorial orbit, and a dedicated ground receiving station (GRS) located at a selected site within the continental United States. The nominal power output of the SPS is established at 5 gigawatts (5 million kilowatts) although, because of various system constraints or losses, it may actually produce between 4 and 5 gigawatts.

Low-Earth orbit satellite servicing economics

NASA Technical Reports Server (NTRS)

Davis, R. F.; Cepollina, F. J.

1982-01-01

Servicing economics of low Earth orbit satellites were studied. The following topics are examined: the economic importance of the repair missions; comparison of mission cost as opposed to satellite modulation transfer functions over a 10 year period; the effect of satellite flight rate change due to changes in satellite failure rate; estimated satellite cost reduction with shuttle operation projects from the 1960's to the 1970's; design objectives of the multimission modular spacecraft; and the economic importance of the repair mission.

Data distribution satellite

NASA Technical Reports Server (NTRS)

Price, Kent M.; Jorasch, Ronald E.; Wiskerchen, Michael J.

1991-01-01

A description is given of a data distribution satellite (DDS) system. The DDS would operate in conjunction with the tracking and data relay satellite system to give ground-based users real time, two-way access to instruments in space and space-gathered data. The scope of work includes the following: (1) user requirements are derived; (2) communication scenarios are synthesized; (3) system design constraints and projected technology availability are identified; (4) DDS communications payload configuration is derived, and the satellite is designed; (5) requirements for earth terminals and network control are given; (6) system costs are estimated, both life cycle costs and user fees; and (7) technology developments are recommended, and a technology development plan is given. The most important results obtained are as follows: (1) a satellite designed for launch in 2007 is feasible and has 10 Gb/s capacity, 5.5 kW power, and 2000 kg mass; (2) DDS features include on-board baseband switching, use of Ku- and Ka-bands, multiple optical intersatellite links; and (3) system user costs are competitive with projected terrestrial communication costs.

Ocean surveillance satellites

NASA Astrophysics Data System (ADS)

Laurent, D.

Soviet and U.S. programs involving satellites for surveillance of ships and submarines are discussed, considering differences in approaches. The Soviet program began with the Cosmos 198 in 1967 and the latest, the Cosmos 1400 series, 15 m long and weighing 5 tons, carry radar for monitoring ships and a nuclear reactor for a power supply. Other Soviet spacecraft carrying passive microwave sensors and ion drives powered by solar panels have recently been detonated in orbit for unknown reasons. It has also been observed that the Soviet satellites are controlled in pairs, with sequential orbital changes for one following the other, and both satellites then overflying the same points. In contrast, U.S. surveillance satellites have been placed in higher orbits, thus placing greater demands on the capabilities of the on-board radar and camera systems. Project White Cloud and the Clipper Bow program are described, noting the continued operation of the White Cloud spacecraft, which are equipped to intercept radio signals from surface ships. Currently, the integrated tactical surveillance system program has completed its study and a decision is expected soon.

Quarantine constraints as applied to satellites.

NASA Technical Reports Server (NTRS)

Hoffman, A. R.; Stavro, W.; Gonzalez, C.

1973-01-01

Plans for unmanned missions to planets beyond Mars in the 1970s include satellite encounters. Recently published observations of data for Titan, a satellite of Saturn, indicate that conditions may be hospitable for the growth of microorganisms. Therefore, the problem of satisfying possible quarantine constraints for outer planet satellites was investigated. This involved determining the probability of impacting a satellite of Jupiter or Saturn by a spacecraft for a planned satellite encounter during an outer planet mission. Mathematical procedures were formulated which (1) determine the areas in the aim-plane that would result in trajectories that impact the satellite and (2) provide a technique for numerically integrating the navigation error function over the impact area to obtain impact probabilities. The results indicate which of the planned spacecraft trajectory correction maneuvers are most critical in terms of satellite quarantine violation.

Quarantine constraints as applied to satellites

NASA Technical Reports Server (NTRS)

Hoffman, A. R.; Stavro, W.; Gonzalez, C. C.

1973-01-01

Plans for unmanned missions to planets beyond Mars in the 1970s include satellite encounters. Recently published observations of data for Titan, a satellite of Saturn, indicate that conditions may be hospitable for the growth of microorganisms. Therefore, the problem of satisfying possible quarantine constraints for outer planet satellites was investigated. This involved determining the probability of impacting a satellite of Jupiter or Saturn by a spacecraft for a planned satellite encounter during an outer planet mission. Mathematical procedures were formulated which determine the areas in the aim-plane that would result in trajectories that impact the satellite and provide a technique for numerically integrating the navigation error function over the impact area to obtain impact probabilities. The results indicate which of the planned spacecraft trajectory correction maneuvers are most critical in terms of satellite quarantine violation.

Radiation processing techniques in remediation of pollutants, and the role of the IAEA in supporting capacity building in developing countries

NASA Astrophysics Data System (ADS)

Haji-Saeid, S. Mohammad.; Sampa, M. H.; Safrany, A.; Sabharwal, S.; Ramamoorthy, N.

2012-08-01

Radiation treatment, or a combination of radiation with conventional biological-chemical-physical processes, can help in the remediation of contaminated surfaces and in combating industrial chemical effluents and air pollution. The use of ionizing radiation as a powerful tool for inactivation of microbes is a valuable option to address likely threats from biohazard contamination that could be introduced either deliberately or inadvertently into areas where the public are exposed to, as well as for treatment of volatile organic compounds and similar hazardous chemical agents is an emerging development in tackling harmful pollutants. The role of the IAEA has been crucial both in supporting the development of local capabilities as well as in fostering international cooperation due to the multidisciplinary expertise required for achieving sustainable benefits. The IAEA is implementing Coordinated Research Projects, (CRP) thematic topical reviews of issues and challenges involved, and Technical Cooperation (TC) assistance in establishing and maintaining infrastructure in the MS. This paper will give an insight into the above mentioned IAEA activities, with examples of successes achieved through CRPs, as well as challenges on the road for broader dissemination of radiation processing technology for environmental remediation.

On-Orbit Calibration of a Multi-Spectral Satellite Satellite Sensor Using a High Altitude Airborne Imaging Spectrometer

NASA Technical Reports Server (NTRS)

Green, R. O.; Shimada, M.

1996-01-01

Earth-looking satellites must be calibrated in order to quantitatively measure and monitor components of land, water and atmosphere of the Earth system. The inevitable change in performance due to the stress of satellite launch requires that the calibration of a satellite sensor be established and validated on-orbit. A new approach to on-orbit satellite sensor calibration has been developed using the flight of a high altitude calibrated airborne imaging spectrometer below a multi-spectral satellite sensor.

Muscle satellite cell heterogeneity and self-renewal

PubMed Central

Motohashi, Norio; Asakura, Atsushi

2014-01-01

Adult skeletal muscle possesses extraordinary regeneration capacities. After muscle injury or exercise, large numbers of newly formed muscle fibers are generated within a week as a result of expansion and differentiation of a self-renewing pool of muscle stem cells termed muscle satellite cells. Normally, satellite cells are mitotically quiescent and reside beneath the basal lamina of muscle fibers. Upon regeneration, satellite cells are activated, and give rise to daughter myogenic precursor cells. After several rounds of proliferation, these myogenic precursor cells contribute to the formation of new muscle fibers. During cell division, a minor population of myogenic precursor cells returns to quiescent satellite cells as a self-renewal process. Currently, accumulating evidence has revealed the essential roles of satellite cells in muscle regeneration and the regulatory mechanisms, while it still remains to be elucidated how satellite cell self-renewal is molecularly regulated and how satellite cells are important in aging and diseased muscle. The number of satellite cells is decreased due to the changing niche during ageing, resulting in attenuation of muscle regeneration capacity. Additionally, in Duchenne muscular dystrophy (DMD) patients, the loss of satellite cell regenerative capacity and decreased satellite cell number due to continuous needs for satellite cells lead to progressive muscle weakness with chronic degeneration. Thus, it is necessary to replenish muscle satellite cells continuously. This review outlines recent findings regarding satellite cell heterogeneity, asymmetric division and molecular mechanisms in satellite cell self-renewal which is crucial for maintenance of satellite cells as a muscle stem cell pool throughout life. In addition, we discuss roles in the stem cell niche for satellite cell maintenance, as well as related cell therapies for approaching treatment of DMD. PMID:25364710