Pasadena, CA, United States
Pasadena, CA, United States

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Creutzfeldt B.,German Research Center for Geosciences | Guntner A.,German Research Center for Geosciences | Wziontek H.,Agency Systems | Merz B.,German Research Center for Geosciences
Geophysical Journal International | Year: 2010

Temporal gravimeter observations, used in geodesy and geophysics to study the Earth's gravity field variations, are influenced by local water storage changes (WSC). At the Geodetic Observatory Wettzell (Germany), WSC in the snow pack, top soil, unsaturated saprolite and fractured aquifer are all important terms of the local water budget. In this study, lysimeter measurements are used for the first time to estimate the hydrological influence on temporal gravimeter observations. Lysimeter data are used to estimate WSC at the field scale in combination with complementary observations and a hydrological 1-D model. From these estimated WSC, we calculate the hydrological gravity response. The results are compared to other methods used in the past to correct temporal gravity observations for the local hydrological influence. Lysimeter measurements significantly improve the independent estimation of WSC and thus provide a better way of reducing the local hydrological effect from gravimeter measurements. We find that the gravity residuals are caused to a larger extent by local WSC than previously stated. At sites where temporal gravity observations are used to study geophysical processes beyond local hydrology, the installation of a lysimeter is recommended. © 2010 The Authors Journal compilation © 2010 RAS.


Grant
Agency: European Commission | Branch: FP7 | Program: CSA-CA | Phase: INFRA-2008-3.0.1 | Award Amount: 1.88M | Year: 2009

The South-East European eInfrastructure initiatives aim to ensure equal participation of the region in European networking and Grid computing trends. SEEREN initiative has established regional network and SEE-GRID the regional Grid. SEE-LIGHT project is currently establishing dark-fibre backbone in the region, and SEE-GRID-SCI empowering strategic regional user communities in common use of the eInfrastructure. Close collaboration of National Research & Education Networks and National Grid Initiatives in the region was crucial in materialising this vision. The above initiatives have also raised awareness of national ministries for the necessity of local programmes and financial support for eInfrastructures: a number of ministries have contributed to local network funding and regional interconnections, as well as national Grid programmes. SEERA-EI will capitalise on this momentum and link national-level programme managers and provide an open forum for information exchange, in order to enable coordination of national programmes in eInfrastructures, and to set the framework for a common regional agenda. The project will gather and exchange information regarding current programmes and carry out a state-of-the-art analysis; produce set of best practices and guidelines for national eInfrastructure programmes; and identify areas for joint regional activities, ranging from short-term soft actions, mid-term policy-level actions, to preparatory activities for long-term actions. SEERA-EI will reduce fragmentation of national programmes, create a harmonised approach to national-level initiatives in eInfrastructures, ensure local commitment, and pave the way towards common regional vision, strategy and sustainable cooperation which will give the region a common voice on European and international stage and strengthen the ERA as a whole, enabling collaborative high-quality research across a spectrum of scientific fields.


Cheng B.-N.,Lincoln Laboratory | Wheeler J.,Lincoln Laboratory | Hung B.,Agency Systems
IEEE Communications Magazine | Year: 2013

The increased usage of net-centric IP applications at the tactical edge has pushed DoD communications systems to maximize bandwidth efficiency amid a limited availability of RF spectrum. One method of increasing bandwidth efficiency (especially with the desire to move to IPv6), is the use of IP header compression (IPHC) to compress headers from the network layer and above into small identifiers before sending to the link layer. Although widely used in cell phone technology, the tactical edge provides some unique challenges to traditional IPHC techniques including highly dynamic links and link conditions due to potential jamming threats and difficult environments, multi-hop scenarios due to lack of infrastructure, and a highly diverse set of radio systems lacking interoperability. In this article, we examine two common IP header compression schemes, Robust Header Compression (RFC 5225) and IP Header Compression (RFC 2507) and one experimental scheme, MANET IP header compression, and identify their current use and applicability in the tactical edge. Furthermore, we identify some challenges in implementing header compression schemes in emerging systems. © 2013 IEEE.


Tiranti D.,Agency Systems | Deangeli C.,Polytechnic University of Turin
Frontiers in Earth Sciences | Year: 2015

A method to predict the most probable flow rheology in Alpine debris flows is presented. The methods classifies outcropping rock masses in catchments on the basis of the type of resulting unconsolidated deposits. The grain size distribution of the debris material and the depositional style of past debris flow events are related to the dominant flow processes: viscoplastic and frictional/collisional. Three catchments in the upper Susa Valley (Western Alps), characterized by different lithologies, were selected for numerical analysis carried out with a Cellular Automata code with viscoplastic and frictional/collisional rheologies. The obtained numerical results are in good agreement with in site evidences in terms of depositional patterns, confirming the possibility of choosing the rheology of the debris flow based on the source material within the catchment. © 2015 Tiranti and Deangeli.


Knab J.J.,Agency Systems
IEEE Transactions on Aerospace and Electronic Systems | Year: 2012

Today, the Wideband Global SATCOM (WGS) system employs a new concept of adjusting the transponder power gain of individual links. A simple optimum method is derived for selecting these individual channel gains to minimize the amount of transponder power utilized. This new method directly solves a set of simple nonlinear equations and does not utilize any search algorithms or matrix inversions thus allowing it to be used with any number of links in a transponder. © 2006 IEEE.


Gormley W.,USAID CapacityPlus Project TRG | McCaffery J.,USAID CapacityPlus Project TRG | Quain E.E.,Agency Systems
Journal of Acquired Immune Deficiency Syndromes | Year: 2011

In 2008, the Global Health Workforce Alliance commissioned a technical working group to examine the human resources for health implications of scaling up to reach the Millennium Development Goal 6 of universal access to HIV/AIDS prevention, treatment, care, and support by 2010. The analysis and interventions recommended in the working group report, which was launched at the Second Global Forum on Human Resources for Health in Bangkok, Thailand, in January 2011, are based on two research methods: literature reviews covering the period from 2000 to 2008 and a rapid situational analysis produced by teams working in 5 countries (Côte d'Ivoire, Ethiopia, Mozambique, Thailand, and Zambia). The authors' intent in this article is to assist the Alliance in maintaining the momentum of the forum and the enthusiasm generated by the working group's report to make a difference at the country level by moving from recommendation to action. © 2011 by Lippincott Williams & Wilkins.


Knab J.J.,Agency Systems
IEEE Transactions on Aerospace and Electronic Systems | Year: 2013

The work presented here gives new methods to calculate the required satellite transponder power as well as required terminal power for an entire network of terminals on the transponder. These methods allow the system designer to choose the smallest terminals to meet the required data rates and to see the effects on the required satellite power. Several equations tie together all system parameters for a commercial satellite network including all ground terminals. These results are easily extended to the military case where the transponder gain is specified. © 1965-2011 IEEE.


Grant
Agency: GTR | Branch: Innovate UK | Program: | Phase: Innovation Voucher | Award Amount: 5.00K | Year: 2013

We have access to sub contractors that have the expertise required to extract and format data sets. We do not have a chosen supplier yet for IP, design or technological research.


Grant
Agency: NSF | Branch: Contract Interagency Agreement | Program: | Phase: ANTARCTIC LOGISTICS SUPPORT | Award Amount: 3.79M | Year: 2014

None


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