Land-surface parameter optimisation using data assimilation techniques: the adJULES system V1.0
NASA Astrophysics Data System (ADS)
Raoult, Nina M.; Jupp, Tim E.; Cox, Peter M.; Luke, Catherine M.
2016-08-01
Land-surface models (LSMs) are crucial components of the Earth system models (ESMs) that are used to make coupled climate-carbon cycle projections for the 21st century. The Joint UK Land Environment Simulator (JULES) is the land-surface model used in the climate and weather forecast models of the UK Met Office. JULES is also extensively used offline as a land-surface impacts tool, forced with climatologies into the future. In this study, JULES is automatically differentiated with respect to JULES parameters using commercial software from FastOpt, resulting in an analytical gradient, or adjoint, of the model. Using this adjoint, the adJULES parameter estimation system has been developed to search for locally optimum parameters by calibrating against observations. This paper describes adJULES in a data assimilation framework and demonstrates its ability to improve the model-data fit using eddy-covariance measurements of gross primary production (GPP) and latent heat (LE) fluxes. adJULES also has the ability to calibrate over multiple sites simultaneously. This feature is used to define new optimised parameter values for the five plant functional types (PFTs) in JULES. The optimised PFT-specific parameters improve the performance of JULES at over 85 % of the sites used in the study, at both the calibration and evaluation stages. The new improved parameters for JULES are presented along with the associated uncertainties for each parameter.
Land-surface parameter optimisation using data assimilation techniques: the adJULES system V1.0
Raoult, Nina M.; Jupp, Tim E.; Cox, Peter M.; ...
2016-08-25
Land-surface models (LSMs) are crucial components of the Earth system models (ESMs) that are used to make coupled climate–carbon cycle projections for the 21st century. The Joint UK Land Environment Simulator (JULES) is the land-surface model used in the climate and weather forecast models of the UK Met Office. JULES is also extensively used offline as a land-surface impacts tool, forced with climatologies into the future. In this study, JULES is automatically differentiated with respect to JULES parameters using commercial software from FastOpt, resulting in an analytical gradient, or adjoint, of the model. Using this adjoint, the adJULES parameter estimationmore » system has been developed to search for locally optimum parameters by calibrating against observations. This paper describes adJULES in a data assimilation framework and demonstrates its ability to improve the model–data fit using eddy-covariance measurements of gross primary production (GPP) and latent heat (LE) fluxes. adJULES also has the ability to calibrate over multiple sites simultaneously. This feature is used to define new optimised parameter values for the five plant functional types (PFTs) in JULES. The optimised PFT-specific parameters improve the performance of JULES at over 85 % of the sites used in the study, at both the calibration and evaluation stages. Furthermore, the new improved parameters for JULES are presented along with the associated uncertainties for each parameter.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Raoult, Nina M.; Jupp, Tim E.; Cox, Peter M.
Land-surface models (LSMs) are crucial components of the Earth system models (ESMs) that are used to make coupled climate–carbon cycle projections for the 21st century. The Joint UK Land Environment Simulator (JULES) is the land-surface model used in the climate and weather forecast models of the UK Met Office. JULES is also extensively used offline as a land-surface impacts tool, forced with climatologies into the future. In this study, JULES is automatically differentiated with respect to JULES parameters using commercial software from FastOpt, resulting in an analytical gradient, or adjoint, of the model. Using this adjoint, the adJULES parameter estimationmore » system has been developed to search for locally optimum parameters by calibrating against observations. This paper describes adJULES in a data assimilation framework and demonstrates its ability to improve the model–data fit using eddy-covariance measurements of gross primary production (GPP) and latent heat (LE) fluxes. adJULES also has the ability to calibrate over multiple sites simultaneously. This feature is used to define new optimised parameter values for the five plant functional types (PFTs) in JULES. The optimised PFT-specific parameters improve the performance of JULES at over 85 % of the sites used in the study, at both the calibration and evaluation stages. Furthermore, the new improved parameters for JULES are presented along with the associated uncertainties for each parameter.« less
Improving the Fit of a Land-Surface Model to Data Using its Adjoint
NASA Astrophysics Data System (ADS)
Raoult, N.; Jupp, T. E.; Cox, P. M.; Luke, C.
2015-12-01
Land-surface models (LSMs) are of growing importance in the world of climate prediction. They are crucial components of larger Earth system models that are aimed at understanding the effects of land surface processes on the global carbon cycle. The Joint UK Land Environment Simulator (JULES) is the land-surface model used by the UK Met Office. It has been automatically differentiated using commercial software from FastOpt, resulting in an analytical gradient, or 'adjoint', of the model. Using this adjoint, the adJULES parameter estimation system has been developed, to search for locally optimum parameter sets by calibrating against observations. adJULES presents an opportunity to confront JULES with many different observations, and make improvements to the model parameterisation. In the newest version of adJULES, multiple sites can be used in the calibration, to giving a generic set of parameters that can be generalised over plant functional types. We present an introduction to the adJULES system and its applications to data from a variety of flux tower sites. We show that calculation of the 2nd derivative of JULES allows us to produce posterior probability density functions of the parameters and how knowledge of parameter values is constrained by observations.
Improving the Fit of a Land-Surface Model to Data Using its Adjoint
NASA Astrophysics Data System (ADS)
Raoult, Nina; Jupp, Tim; Cox, Peter; Luke, Catherine
2016-04-01
Land-surface models (LSMs) are crucial components of the Earth System Models (ESMs) which are used to make coupled climate-carbon cycle projections for the 21st century. The Joint UK Land Environment Simulator (JULES) is the land-surface model used in the climate and weather forecast models of the UK Met Office. In this study, JULES is automatically differentiated using commercial software from FastOpt, resulting in an analytical gradient, or adjoint, of the model. Using this adjoint, the adJULES parameter estimation system has been developed, to search for locally optimum parameter sets by calibrating against observations. We present an introduction to the adJULES system and demonstrate its ability to improve the model-data fit using eddy covariance measurements of gross primary production (GPP) and latent heat (LE) fluxes. adJULES also has the ability to calibrate over multiple sites simultaneously. This feature is used to define new optimised parameter values for the 5 Plant Functional Types (PFTS) in JULES. The optimised PFT-specific parameters improve the performance of JULES over 90% of the FLUXNET sites used in the study. These reductions in error are shown and compared to reductions found due to site-specific optimisations. Finally, we show that calculation of the 2nd derivative of JULES allows us to produce posterior probability density functions of the parameters and how knowledge of parameter values is constrained by observations.
NASA Astrophysics Data System (ADS)
Chou, H. K.; Ochoa-Tocachi, B. F.; Buytaert, W.
2017-12-01
Community land surface models such as JULES are increasingly used for hydrological assessment because of their state-of-the-art representation of land-surface processes. However, a major weakness of JULES and other land surface models is the limited number of land surface parameterizations that is available. Therefore, this study explores the use of data from a network of catchments under homogeneous land-use to generate parameter "libraries" to extent the land surface parameterizations of JULES. The network (called iMHEA) is part of a grassroots initiative to characterise the hydrological response of different Andean ecosystems, and collects data on streamflow, precipitation, and several weather variables at a high temporal resolution. The tropical Andes are a useful case study because of the complexity of meteorological and geographical conditions combined with extremely heterogeneous land-use that result in a wide range of hydrological responses. We then calibrated JULES for each land-use represented in the iMHEA dataset. For the individual land-use types, the results show improved simulations of streamflow when using the calibrated parameters with respect to default values. In particular, the partitioning between surface and subsurface flows can be improved. But also, on a regional scale, hydrological modelling was greatly benefitted from constraining parameters using such distributed citizen-science generated streamflow data. This study demonstrates the modelling and prediction on regional hydrology by integrating citizen science and land surface model. In the context of hydrological study, the limitation of data scarcity could be solved indeed by using this framework. Improved predictions of such impacts could be leveraged by catchment managers to guide watershed interventions, to evaluate their effectiveness, and to minimize risks.
NASA Astrophysics Data System (ADS)
Comyn-Platt, Edward; Clark, Douglas; Blyth, Eleanor
2016-04-01
The UK is required to provide accurate estimates of the UK greenhouse gas (GHG; CO2, CH4 and N2O) emissions for the UNFCCC (United Nations Framework Convention on Climate Change). Process based land surface models (LSMs), such as the Joint UK Land Environment Simulator (JULES), attempt to provide such estimates based on environmental (e.g. land use and soil type) and meteorological conditions. The standard release of JULES focusses on the water and carbon cycles, however, it has long been suggested that a coupled carbon-nitrogen scheme could enhance simulations. This is of particular importance when estimating agricultural emission inventories where the carbon cycle is effectively managed via the human application of nitrogen based fertilizers. JULES-ECOSSE-FUN (JEF) links JULES with the Estimation of Carbon in Organic Soils - Sequestration and Emission (ECOSSE) model and the Fixation and Uptake of Nitrogen (FUN) model as a means of simulating C:N coupling. This work presents simulations from the standard release of JULES and the most recent incarnation of the JEF coupled system at the point and field scale. Various configurations of JULES and JEF were calibrated and fine-tuned based on comparisons with observations from three UK field campaigns (Crichton, Harwood Forest and Brattleby) specifically chosen to represent the managed vegetation types that cover the UK. The campaigns included flux tower and chamber measurements of CO2, CH4 and N2O amongst other meteorological parameters and records of land management such as application of fertilizer and harvest date at the agricultural sites. Based on the results of these comparisons, JULES and/or JEF will be used to provide simulations on the regional and national scales in order to provide improved estimates of the total UK emission inventory.
NASA Astrophysics Data System (ADS)
Clark, D. B.; Mercado, L. M.; Sitch, S.; Jones, C. D.; Gedney, N.; Best, M. J.; Pryor, M.; Rooney, G. G.; Essery, R. L. H.; Blyth, E.; Boucher, O.; Harding, R. J.; Cox, P. M.
2011-03-01
The Joint UK Land Environment Simulator (JULES) is a process-based model that simulates the fluxes of carbon, water, energy and momentum between the land surface and the atmosphere. Past studies with JULES have demonstrated the important role of the land surface in the Earth System. Different versions of JULES have been employed to quantify the effects on the land carbon sink of separately changing atmospheric aerosols and tropospheric ozone, and the response of methane emissions from wetlands to climate change. There was a need to consolidate these and other advances into a single model code so as to be able to study interactions in a consistent manner. This paper describes the consolidation of these advances into the modelling of carbon fluxes and stores, in the vegetation and soil, in version 2.2 of JULES. Features include a multi-layer canopy scheme for light interception, including a sunfleck penetration scheme, a coupled scheme of leaf photosynthesis and stomatal conductance, representation of the effects of ozone on leaf physiology, and a description of methane emissions from wetlands. JULES represents the carbon allocation, growth and population dynamics of five plant functional types. The turnover of carbon from living plant tissues is fed into a 4-pool soil carbon model. The process-based descriptions of key ecological processes and trace gas fluxes in JULES mean that this community model is well-suited for use in carbon cycle, climate change and impacts studies, either in standalone mode or as the land component of a coupled Earth system model.
NASA Astrophysics Data System (ADS)
Clark, D. B.; Mercado, L. M.; Sitch, S.; Jones, C. D.; Gedney, N.; Best, M. J.; Pryor, M.; Rooney, G. G.; Essery, R. L. H.; Blyth, E.; Boucher, O.; Harding, R. J.; Huntingford, C.; Cox, P. M.
2011-09-01
The Joint UK Land Environment Simulator (JULES) is a process-based model that simulates the fluxes of carbon, water, energy and momentum between the land surface and the atmosphere. Many studies have demonstrated the important role of the land surface in the functioning of the Earth System. Different versions of JULES have been employed to quantify the effects on the land carbon sink of climate change, increasing atmospheric carbon dioxide concentrations, changing atmospheric aerosols and tropospheric ozone, and the response of methane emissions from wetlands to climate change. This paper describes the consolidation of these advances in the modelling of carbon fluxes and stores, in both the vegetation and soil, in version 2.2 of JULES. Features include a multi-layer canopy scheme for light interception, including a sunfleck penetration scheme, a coupled scheme of leaf photosynthesis and stomatal conductance, representation of the effects of ozone on leaf physiology, and a description of methane emissions from wetlands. JULES represents the carbon allocation, growth and population dynamics of five plant functional types. The turnover of carbon from living plant tissues is fed into a 4-pool soil carbon model. The process-based descriptions of key ecological processes and trace gas fluxes in JULES mean that this community model is well-suited for use in carbon cycle, climate change and impacts studies, either in standalone mode or as the land component of a coupled Earth system model.
JULES-crop: a parametrisation of crops in the Joint UK Land Environment Simulator
NASA Astrophysics Data System (ADS)
Osborne, T.; Gornall, J.; Hooker, J.; Williams, K.; Wiltshire, A.; Betts, R.; Wheeler, T.
2014-10-01
Studies of climate change impacts on the terrestrial biosphere have been completed without recognition of the integrated nature of the biosphere. Improved assessment of the impacts of climate change on food and water security requires the development and use of models not only representing each component but also their interactions. To meet this requirement the Joint UK Land Environment Simulator (JULES) land surface model has been modified to include a generic parametrisation of annual crops. The new model, JULES-crop, is described and evaluation at global and site levels for the four globally important crops; wheat, soy bean, maize and rice is presented. JULES-crop demonstrates skill in simulating the inter-annual variations of yield for maize and soy bean at the global level, and for wheat for major spring wheat producing countries. The impact of the new parametrisation, compared to the standard configuration, on the simulation of surface heat fluxes is largely an alteration of the partitioning between latent and sensible heat fluxes during the later part of the growing season. Further evaluation at the site level shows the model captures the seasonality of leaf area index and canopy height better than in standard JULES. However, this does not lead to an improvement in the simulation of sensible and latent heat fluxes. The performance of JULES-crop from both an earth system and crop yield model perspective is encouraging however, more effort is needed to develop the parameterisation of the model for specific applications. Key future model developments identified include the specification of the yield gap to enable better representation of the spatial variability in yield.
Towards a simple representation of chalk hydrology in land surface modelling
NASA Astrophysics Data System (ADS)
Rahman, Mostaquimur; Rosolem, Rafael
2017-01-01
Modelling and monitoring of hydrological processes in the unsaturated zone of chalk, a porous medium with fractures, is important to optimize water resource assessment and management practices in the United Kingdom (UK). However, incorporating the processes governing water movement through a chalk unsaturated zone in a numerical model is complicated mainly due to the fractured nature of chalk that creates high-velocity preferential flow paths in the subsurface. In general, flow through a chalk unsaturated zone is simulated using the dual-porosity concept, which often involves calibration of a relatively large number of model parameters, potentially undermining applications to large regions. In this study, a simplified parameterization, namely the Bulk Conductivity (BC) model, is proposed for simulating hydrology in a chalk unsaturated zone. This new parameterization introduces only two additional parameters (namely the macroporosity factor and the soil wetness threshold parameter for fracture flow activation) and uses the saturated hydraulic conductivity from the chalk matrix. The BC model is implemented in the Joint UK Land Environment Simulator (JULES) and applied to a study area encompassing the Kennet catchment in the southern UK. This parameterization is further calibrated at the point scale using soil moisture profile observations. The performance of the calibrated BC model in JULES is assessed and compared against the performance of both the default JULES parameterization and the uncalibrated version of the BC model implemented in JULES. Finally, the model performance at the catchment scale is evaluated against independent data sets (e.g. runoff and latent heat flux). The results demonstrate that the inclusion of the BC model in JULES improves simulated land surface mass and energy fluxes over the chalk-dominated Kennet catchment. Therefore, the simple approach described in this study may be used to incorporate the flow processes through a chalk unsaturated zone in large-scale land surface modelling applications.
Evaluation of modelled methane emissions over northern peatland sites
NASA Astrophysics Data System (ADS)
Gao, Yao; Burke, Eleanor; Chadburn, Sarah; Raivonen, Maarit; Susiluoto, Jouni; Vesala, Timo; Aurela, Mika; Lohila, Annalea; Aalto, Tuula
2017-04-01
Methane (CH4) is a powerful greenhouse gas, with approximately 34 times the global warming potential of carbon dioxide (CO2) over a century time horizon (IPCC, 2013). The strong sensitivity of methane emissions to environmental factors has led to concerns about potential positive feedbacks to climate change. Evaluation of the ability of the process-based land surface models of earth system models (ESMs) in simulating CH4 emission over peatland is needed for more precise future predictions. In this study, two peatland sites of poor and rich soil nutrient conditions, in southern and northern Finland respectively, are adopted. The measured CH4 fluxes at the two sites are used to evaluate the CH4 emissions simulated by the land surface model (JULES) of the UK Earth System model and by the Helsinki peatland methane emission model (HIMMELI), which is developed at Finnish Meteorological Institute and Helsinki University. In JULES, CH4 flux is simply related to soil temperature, wetland fraction and effective substrate availability. However, HIMMELI has detailed descriptions of microbial and transport processes for simulating CH4 flux. The seasonal dynamics of CH4 fluxes at the two sites are relatively well captured by both models, but model biases exist. Simulated CH4 flux is sensitive to water table depth (WTD) at both models. However, the simulated WTD is limited to be below ground in JULES. It is also important to have the annual cycle of LAI correct when coupling JULES with HIMMELI.
Revising Hydrology of a Land Surface Model
NASA Astrophysics Data System (ADS)
Le Vine, Nataliya; Butler, Adrian; McIntyre, Neil; Jackson, Christopher
2015-04-01
Land Surface Models (LSMs) are key elements in guiding adaptation to the changing water cycle and the starting points to develop a global hyper-resolution model of the terrestrial water, energy and biogeochemical cycles. However, before this potential is realised, there are some fundamental limitations of LSMs related to how meaningfully hydrological fluxes and stores are represented. An important limitation is the simplistic or non-existent representation of the deep subsurface in LSMs; and another is the lack of connection of LSM parameterisations to relevant hydrological information. In this context, the paper uses a case study of the JULES (Joint UK Land Environmental Simulator) LSM applied to the Kennet region in Southern England. The paper explores the assumptions behind JULES hydrology, adapts the model structure and optimises the coupling with the ZOOMQ3D regional groundwater model. The analysis illustrates how three types of information can be used to improve the model's hydrology: a) observations, b) regionalized information, and c) information from an independent physics-based model. It is found that: 1) coupling to the groundwater model allows realistic simulation of streamflows; 2) a simple dynamic lower boundary improves upon JULES' stationary unit gradient condition; 3) a 1D vertical flow in the unsaturated zone is sufficient; however there is benefit in introducing a simple dual soil moisture retention curve; 4) regionalized information can be used to describe soil spatial heterogeneity. It is concluded that relatively simple refinements to the hydrology of JULES and its parameterisation method can provide a substantial step forward in realising its potential as a high-resolution multi-purpose model.
NASA Technical Reports Server (NTRS)
Santanello, Joseph
2011-01-01
NASA's Land Information System (LIS; lis.gsfc.nasa.gov) is a flexible land surface modeling and data assimilation framework developed over the past decade with the goal of integrating satellite- and ground-based observational data products and advanced land surface modeling techniques to produce optimal fields of land surface states and fluxes. LIS features a high performance and flexible design, and operates on an ensemble of land surface models for extension over user-specified regional or global domains. The extensible interfaces of LIS allow the incorporation of new domains, land surface models (LSMs), land surface parameters, meteorological inputs, data assimilation and optimization algorithms. In addition, LIS has also been demonstrated for parameter estimation and uncertainty estimation, and has been coupled to the Weather Research and Forecasting (WRF) mesoscale model. A visiting fellowship is currently underway to implement JULES into LIS and to undertake some fundamental science on the feedbacks between the land surface and the atmosphere. An overview of the LIS system, features, and sample results will be presented in an effort to engage the community in the potential advantages of LIS-JULES for a range of applications. Ongoing efforts to develop a framework for diagnosing land-atmosphere coupling will also be presented using the suite of LSM and PBL schemes available in LIS and WRF along with observations from the U. S .. Southern Great Plains. This methodology provides a potential pathway to study factors controlling local land-atmosphere coupling (LoCo) using the LIS-WRF system, which will serve as a testbed for future experiments to evaluate coupling diagnostics within the community.
NASA Astrophysics Data System (ADS)
Leung, F.
2016-12-01
Tropospheric ozone (O3) is the third most important anthropogenic greenhouse gas. It is causing significant crop production losses. Currently, O3 concentrations are projected to increase globally, which could have a significant impact on food security. The Joint UK Land Environment Simulator modified to include crops (JULES-crop) is used here to quantify the impacts of tropospheric O3 on crop production at the regional scale until 2100. We evaluate JULES-crop against the Soybean Free-Air-Concentration-Enrichment (SoyFACE) experiment in Illinois, USA. Experimental data from SoyFACE and various literature sources is used to calibrate the parameters for soybean and ozone damage parameters in soybean in JULES-crop. The calibrated model is then applied for a transient factorial set of JULES-crop simulations over 1960-2005. Simulated yield changes are attributed to individual environmental drivers, CO2, O3 and climate change, across regions and for different crops. A mixed scenario of RCP 2.6 and RCP 8.5 climatology and ozone are simulated to explore the implication of policy. The overall findings are that regions with high ozone concentration such as China and India suffer the most from ozone damage, soybean is more sensitive to O3 than other crops. JULES-crop predicts CO2 fertilisation would increase the productivity of vegetation. This effect, however, is masked by the negative impacts of tropospheric O3. Using data from FAO and JULES-crop estimated that ozone damage cost around 55.4 Billion USD per year on soybean. Irrigation improves the simulation of rice only, and it increases the relative ozone damage because drought can reduce the ozone from entering the plant stomata. RCP 8.5 scenario results in a high yield for all crops mainly due to the CO2 fertilisation effect. Mixed climate scenarios simulations suggest that RCP 8.5 CO2 concentration and RCP 2.6 O3 concentration result in the highest yield. Further works such as more crop FACE-O3 experiments and more Crop functional types in JULES are necessary. The model will thus contribute to a complete understanding of the impacts of climate change on food production. JULES will be later coupled with the Unified Model to quantify the impact of tropospheric O3 on crops productivity including feedbacks between the land-surface, atmospheric chemistry and climate change.
Performance of the JULES land surface model for UK Biogenic VOC emissions
NASA Astrophysics Data System (ADS)
Hayman, Garry; Comyn-Platt, Edward; Vieno, Massimo; Langford, Ben
2017-04-01
Emissions of biogenic non-methane volatile organic compounds (NMVOCs) are important for air quality and tropospheric composition. Through their contribution to the production of tropospheric ozone and secondary organic aerosol (SOA), biogenic VOCs indirectly contribute to climate forcing and climate feedbacks [1]. Biogenic VOCs encompass a wide range of compounds and are produced by plants for growth, development, reproduction, defence and communication [2]. There are both biological and physico-chemical controls on emissions [3]. Only a few of the many biogenic VOCs are of wider interest and only two or three (isoprene and the monoterpenes, α- and β-pinene) are represented in chemical transport models. We use the Joint UK Land Environment Simulator (JULES), the UK community land surface model, to estimate biogenic VOC emission fluxes. JULES is a process-based model that describes the water, energy and carbon balances and includes temperature, moisture and carbon stores [4, 5]. JULES currently provides emission fluxes of the 4 largest groups of biogenic VOCs: isoprene, terpenes, methanol and acetone. The JULES isoprene scheme uses gross primary productivity (GPP), leaf internal carbon and the leaf temperature as a proxy for the electron requirement for isoprene synthesis [6]. In this study, we compare JULES biogenic VOC emission estimates of isoprene and terepenes with (a) flux measurements made at selected sites in the UK and Europe and (b) gridded estimates for the UK from the EMEP/EMEP4UK atmospheric chemical transport model [7, 8], using site-specific or EMEP4UK driving meteorological data, respectively. We compare the UK-scale emission estimates with literature estimates. We generally find good agreement in the comparisons but the estimates are sensitive to the choice of the base or reference emission potentials. References (1) Unger, 2014: Geophys. Res. Lett., 41, 8563, doi:10.1002/2014GL061616; (2) Laothawornkitkul et al., 2009: New Phytol., 183, 27, doi:10.1111/j.1469-8137.2009.02859.x; (3) Grote and Niinemets, 2008: Plant Biol., 10, 8, doi:10.1055/s-2007-964975; (4) Best et al., 2011: Geosci. Model Dev., 4, 677, doi:10.5194/gmd-4-677-2011; (5) Clark et al., 2011: Geosci. Model Dev., 4, 701, doi:10.5194/gmd-4-701-2011; (6) Pacifico et al., 2011: Atmos. Chem. Phys., 11, 4371, doi:10.5194/acp-11-4371-2011; [7] Simpson et al., 2012: Atmos. Chem. Phys., 12, 7825, doi: 10.5194/acp-12-7825-2012; [8] Vieno et al., 2016: Atmos. Chem. Phys., 16, 265, doi: 10.5194/acp-16-265-2016.
NASA Astrophysics Data System (ADS)
Le Vine, N.; Butler, A.; McIntyre, N.; Jackson, C.
2015-08-01
Land Surface Models (LSMs) are prospective starting points to develop a global hyper-resolution model of the terrestrial water, energy and biogeochemical cycles. However, there are some fundamental limitations of LSMs related to how meaningfully hydrological fluxes and stores are represented. A diagnostic approach to model evaluation is taken here that exploits hydrological expert knowledge to detect LSM inadequacies through consideration of the major behavioural functions of a hydrological system: overall water balance, vertical water redistribution in the unsaturated zone, temporal water redistribution and spatial water redistribution over the catchment's groundwater and surface water systems. Three types of information are utilised to improve the model's hydrology: (a) observations, (b) information about expected response from regionalised data, and (c) information from an independent physics-based model. The study considers the JULES (Joint UK Land Environmental Simulator) LSM applied to a deep-groundwater chalk catchment in the UK. The diagnosed hydrological limitations and the proposed ways to address them are indicative of the challenges faced while transitioning to a global high resolution model of the water cycle.
NASA Astrophysics Data System (ADS)
Le Vine, N.; Butler, A.; McIntyre, N.; Jackson, C.
2016-01-01
Land surface models (LSMs) are prospective starting points to develop a global hyper-resolution model of the terrestrial water, energy, and biogeochemical cycles. However, there are some fundamental limitations of LSMs related to how meaningfully hydrological fluxes and stores are represented. A diagnostic approach to model evaluation and improvement is taken here that exploits hydrological expert knowledge to detect LSM inadequacies through consideration of the major behavioural functions of a hydrological system: overall water balance, vertical water redistribution in the unsaturated zone, temporal water redistribution, and spatial water redistribution over the catchment's groundwater and surface-water systems. Three types of information are utilized to improve the model's hydrology: (a) observations, (b) information about expected response from regionalized data, and (c) information from an independent physics-based model. The study considers the JULES (Joint UK Land Environmental Simulator) LSM applied to a deep-groundwater chalk catchment in the UK. The diagnosed hydrological limitations and the proposed ways to address them are indicative of the challenges faced while transitioning to a global high resolution model of the water cycle.
Testing the Joint UK Land Environment Simulator (JULES) for flood forecasting
NASA Astrophysics Data System (ADS)
Batelis, Stamatios-Christos; Rosolem, Rafael; Han, Dawei; Rahman, Mostaquimur
2017-04-01
Land Surface Models (LSM) are based on physics principles and simulate the exchanges of energy, water and biogeochemical cycles between the land surface and lower atmosphere. Such models are typically applied for climate studies or effects of land use changes but as the resolution of LSMs and supporting observations are continuously increasing, its representation of hydrological processes need to be addressed adequately. For example, changes in climate and land use can alter the hydrology of a region, for instance, by altering its flooding regime. LSMs can be a powerful tool because of their ability to spatially represent a region with much finer resolution. However, despite such advantages, its performance has not been extensively assessed for flood forecasting simply because its representation of typical hydrological processes, such as overland flow and river routing, are still either ignored or roughly represented. In this study, we initially test the Joint UK Land Environment Simulator (JULES) as a flood forecast tool focusing on its river routing scheme. In particular, JULES river routing parameterization is based on the Rapid Flow Model (RFM) which relies on six prescribed parameters (two surface and two subsurface wave celerities, and two return flow fractions). Although this routing scheme is simple, the prescription of its six default parameters is still too generalized. Our aim is to understand the importance of each RFM parameter in a series of JULES simulations at a number of catchments in the UK for the 2006-2015 period. This is carried out, for instance, by making a number of assumptions of parameter behaviour (e.g., spatially uniform versus varying and/or temporally constant or time-varying parameters within each catchment). Hourly rainfall radar in combination with the CHESS (Climate, Hydrological and Ecological research Support System) meteorological daily data both at 1 km2 resolution are used. The evaluation of the model is based on hourly runoff data provided by the National River Flood Archive using a number of model performance metrics. We use a calibrated conceptually-based lumped model, more typically applied in flood studies, as a benchmark for our analysis.
The Met Office Unified Model Global Atmosphere 6.0/6.1 and JULES Global Land 6.0/6.1 configurations
NASA Astrophysics Data System (ADS)
Walters, David; Boutle, Ian; Brooks, Malcolm; Melvin, Thomas; Stratton, Rachel; Vosper, Simon; Wells, Helen; Williams, Keith; Wood, Nigel; Allen, Thomas; Bushell, Andrew; Copsey, Dan; Earnshaw, Paul; Edwards, John; Gross, Markus; Hardiman, Steven; Harris, Chris; Heming, Julian; Klingaman, Nicholas; Levine, Richard; Manners, James; Martin, Gill; Milton, Sean; Mittermaier, Marion; Morcrette, Cyril; Riddick, Thomas; Roberts, Malcolm; Sanchez, Claudio; Selwood, Paul; Stirling, Alison; Smith, Chris; Suri, Dan; Tennant, Warren; Vidale, Pier Luigi; Wilkinson, Jonathan; Willett, Martin; Woolnough, Steve; Xavier, Prince
2017-04-01
We describe Global Atmosphere 6.0 and Global Land 6.0 (GA6.0/GL6.0): the latest science configurations of the Met Office Unified Model and JULES (Joint UK Land Environment Simulator) land surface model developed for use across all timescales. Global Atmosphere 6.0 includes the ENDGame (Even Newer Dynamics for General atmospheric modelling of the environment) dynamical core, which significantly increases mid-latitude variability improving a known model bias. Alongside developments of the model's physical parametrisations, ENDGame also increases variability in the tropics, which leads to an improved representation of tropical cyclones and other tropical phenomena. Further developments of the atmospheric and land surface parametrisations improve other aspects of model performance, including the forecasting of surface weather phenomena. We also describe GA6.1/GL6.1, which includes a small number of long-standing differences from our main trunk configurations that we continue to require for operational global weather prediction. Since July 2014, GA6.1/GL6.1 has been used by the Met Office for operational global numerical weather prediction, whilst GA6.0/GL6.0 was implemented in its remaining global prediction systems over the following year.
Modeling of Cavitating Flow through Waterjet Propulsors
2015-02-18
1-0197 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Jules W. Lindau 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING...RESPONSIBLE PERSON Jules W. Lindau 19b. TELEPONE NUMBER (Include area code) 814-865-8938 ^\\6^G%013 Standard Form 298 (Rev. 8-98) Prescribed by ANSI-Std...239-18 Modeling of Cavitating Flow through Waterjet Propulsors Jules W. Lindau The Pennsylvania State University, Applied Research Laboratory, State
Representation of Dissolved Organic Carbon in the JULES Dynamic Global Vegetation Model
NASA Astrophysics Data System (ADS)
Nakhavali, Mahdi; Friedlingstein, Pierre; Guenet, Bertrand; Ciais, Philip
2017-04-01
Current global models of the carbon cycle consider only vertical gas exchanges between terrestrial or oceanic reservoirs and the atmosphere, hence not considering lateral transport of carbon from the continent to the oceans. This also means that such models implicitly consider that all the CO2 which is not respired to the atmosphere is stored on land, hence overestimating the land sink of carbon. Moving toward a boundless carbon cycle that is integrating the whole continuum from land to ocean to atmosphere is needed in order to better understand Earth's carbon cycle and to make more reliable projection of its future. Here we present an original representation of Dissolved Organic Carbon (DOC) processes in the Joint UK Land Environment Simulator (JULES). The standard version of JULES represent energy, water and carbon cycles and exchanges with the atmosphere, but only account for water run-off, not including export of carbon from terrestrial ecosystems to the aquatic environments. The aim of the project is to include in JULES a representation of DOC production in terrestrial soils, due to incomplete decomposition of organic matter, its decomposition to the atmosphere, and its export to the river network by leaching. In new developed version of JULES (JULES-DOCM), DOC pools, based on their decomposition rate, are classified into labile and recalcitrant within 3 meters of soil. Based on turnover rate, DOC coming from plant material pools and microbial biomass is directed to labile pool, while DOC from humus is directed to recalcitrant pool. Both of these pools have free (dissolved) and locked (adsorbed) form where just the free pool is subjected to decomposition and leaching. DOC production and decomposition are controlled by rate modifiers (moisture, temperature, vegetation fraction and decomposition rate) at each soil layer. Decomposed DOC is released to the atmosphere following a fixed carbon use efficiency. Leaching accounts for both surface (runoff) and subsurface (groundwater) components and is parameterized as Top soil leaching (from top 20cm) and Bottom soil leaching (down to 3 meters) depending on DOC concentration and runoff leaving that layer. The model parameters are calibrated against specific sites (Brasschaat, Hainich and Carlow) for which observations of DOC concentration and leaching are available. Tuning is performed optimizing parameters such as DOC labile and recalcitrant resident time, DOC vertical distribution and CUE. Once this calibration has been performed at the site level, the model is used for global simulations with the major historical forcing (climate, atmospheric CO2 and land-use changes) in order to estimate the changes of DOC export and their attribution to anthropogenic activities.
Advancement and Application of Multi-Phase CFD Modeling to High Speed Supercavitating Flows
2013-08-13
5a. CONTRACT NUMBER 5b. GRANT NUMBER N00014-09-1-0042 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Jules W. Lindau and Michael P. Kinzel 5d. PROJECT...REPORT U b. ABSTRACT U c. THIS PAGE U 17. LIMITATION OF ABSTRACT U 18. NUMBER OF PAGES 29 19a. NAME OF RESPONSIBLE PERSON Jules W. Lindau...Application of Multi-Phase CFD Modeling to High Speed Supercavitating Flows Michael P. Kinzel Jules W. Lindau Penn State University Applied Research
Quantifying uncertainties of permafrost carbon-climate feedbacks
NASA Astrophysics Data System (ADS)
Burke, Eleanor J.; Ekici, Altug; Huang, Ye; Chadburn, Sarah E.; Huntingford, Chris; Ciais, Philippe; Friedlingstein, Pierre; Peng, Shushi; Krinner, Gerhard
2017-06-01
The land surface models JULES (Joint UK Land Environment Simulator, two versions) and ORCHIDEE-MICT (Organizing Carbon and Hydrology in Dynamic Ecosystems), each with a revised representation of permafrost carbon, were coupled to the Integrated Model Of Global Effects of climatic aNomalies (IMOGEN) intermediate-complexity climate and ocean carbon uptake model. IMOGEN calculates atmospheric carbon dioxide (CO2) and local monthly surface climate for a given emission scenario with the land-atmosphere CO2 flux exchange from either JULES or ORCHIDEE-MICT. These simulations include feedbacks associated with permafrost carbon changes in a warming world. Both IMOGEN-JULES and IMOGEN-ORCHIDEE-MICT were forced by historical and three alternative future-CO2-emission scenarios. Those simulations were performed for different climate sensitivities and regional climate change patterns based on 22 different Earth system models (ESMs) used for CMIP3 (phase 3 of the Coupled Model Intercomparison Project), allowing us to explore climate uncertainties in the context of permafrost carbon-climate feedbacks. Three future emission scenarios consistent with three representative concentration pathways were used: RCP2.6, RCP4.5 and RCP8.5. Paired simulations with and without frozen carbon processes were required to quantify the impact of the permafrost carbon feedback on climate change. The additional warming from the permafrost carbon feedback is between 0.2 and 12 % of the change in the global mean temperature (ΔT) by the year 2100 and 0.5 and 17 % of ΔT by 2300, with these ranges reflecting differences in land surface models, climate models and emissions pathway. As a percentage of ΔT, the permafrost carbon feedback has a greater impact on the low-emissions scenario (RCP2.6) than on the higher-emissions scenarios, suggesting that permafrost carbon should be taken into account when evaluating scenarios of heavy mitigation and stabilization. Structural differences between the land surface models (particularly the representation of the soil carbon decomposition) are found to be a larger source of uncertainties than differences in the climate response. Inertia in the permafrost carbon system means that the permafrost carbon response depends on the temporal trajectory of warming as well as the absolute amount of warming. We propose a new policy-relevant metric - the frozen carbon residence time (FCRt) in years - that can be derived from these complex land surface models and used to quantify the permafrost carbon response given any pathway of global temperature change.
Representation of dissolved organic carbon in the JULES land surface model (vn4.4_JULES-DOCM)
NASA Astrophysics Data System (ADS)
Nakhavali, Mahdi; Friedlingstein, Pierre; Lauerwald, Ronny; Tang, Jing; Chadburn, Sarah; Camino-Serrano, Marta; Guenet, Bertrand; Harper, Anna; Walmsley, David; Peichl, Matthias; Gielen, Bert
2018-02-01
Current global models of the carbon (C) cycle consider only vertical gas exchanges between terrestrial or oceanic reservoirs and the atmosphere, thus not considering the lateral transport of carbon from the continents to the oceans. Therefore, those models implicitly consider all of the C which is not respired to the atmosphere to be stored on land and hence overestimate the land C sink capability. A model that represents the whole continuum from atmosphere to land and into the ocean would provide a better understanding of the Earth's C cycle and hence more reliable historical or future projections. A first and critical step in that direction is to include processes representing the production and export of dissolved organic carbon in soils. Here we present an original representation of dissolved organic C (DOC) processes in the Joint UK Land Environment Simulator (JULES-DOCM) that integrates a representation of DOC production in terrestrial ecosystems based on the incomplete decomposition of organic matter, DOC decomposition within the soil column, and DOC export to the river network via leaching. The model performance is evaluated in five specific sites for which observations of soil DOC concentration are available. Results show that the model is able to reproduce the DOC concentration and controlling processes, including leaching to the riverine system, which is fundamental for integrating terrestrial and aquatic ecosystems. Future work should include the fate of exported DOC in the river system as well as DIC and POC export from soil.
NASA Astrophysics Data System (ADS)
Lee, H.; Park, J.; Cho, S.; Lee, S. J.; Kim, H. S.
2017-12-01
Forest determines the amount of water available to low land ecosystems, which use the rest of water after evapotranspiration by forests. Substantial increase of drought, especially for seasonal drought, has occurred in Korea due to climate change, recently. To cope with this increasing crisis, it is necessary to predict the water use of forest. In our study, forest water use in the Gyeonggi Province in Korea was estimated using high-resolution (spatial and temporal) meteorological forecast data and localized Joint UK Land Environment Simulator (JULES) which is one of the widely used land surface models. The modeled estimation was used for developing forest drought index. The localization of the model was conducted by 1) refining the existing two tree plant functional types (coniferous and deciduous trees) into five (Quercus spp., other deciduous tree spp., Pinus spp., Larix spp., and other coniferous spp.), 2) correcting moderate resolution imaging spectroradiometer (MODIS) leaf area index (LAI) through data assimilation with in situ measured LAI, and 3) optimizing the unmeasured plant physiological parameters (e.g. leaf nitrogen contents, nitrogen distribution within canopy, light use efficiency) based on sensitivity analysis of model output values. The high-resolution (hourly and 810 × 810 m) National Center for AgroMeteorology-Land-Atmosphere Modeling Package (NCAM-LAMP) data were employed as meteorological input data in JULES. The plant functional types and soil texture of each grid cell in the same resolution with that of NCAM-LAMP was also used. The performance of the localized model in estimating forest water use was verified by comparison with the multi-year sapflow measurements and Eddy covariance data of Taehwa Mountain site. Our result can be used as referential information to estimate the forest water use change by the climate change. Moreover, the drought index can be used to foresee the drought condition and prepare to it.
Land-use change may exacerbate climate change impacts on water resources in the Ganges basin
NASA Astrophysics Data System (ADS)
Tsarouchi, Gina; Buytaert, Wouter
2018-02-01
Quantifying how land-use change and climate change affect water resources is a challenge in hydrological science. This work aims to quantify how future projections of land-use and climate change might affect the hydrological response of the Upper Ganges river basin in northern India, which experiences monsoon flooding almost every year. Three different sets of modelling experiments were run using the Joint UK Land Environment Simulator (JULES) land surface model (LSM) and covering the period 2000-2035: in the first set, only climate change is taken into account, and JULES was driven by the CMIP5 (Coupled Model Intercomparison Project Phase 5) outputs of 21 models, under two representative concentration pathways (RCP4.5 and RCP8.5), whilst land use was held fixed at the year 2010. In the second set, only land-use change is taken into account, and JULES was driven by a time series of 15 future land-use pathways, based on Landsat satellite imagery and the Markov chain simulation, whilst the meteorological boundary conditions were held fixed at years 2000-2005. In the third set, both climate change and land-use change were taken into consideration, as the CMIP5 model outputs were used in conjunction with the 15 future land-use pathways to force JULES. Variations in hydrological variables (stream flow, evapotranspiration and soil moisture) are calculated during the simulation period. Significant changes in the near-future (years 2030-2035) hydrologic fluxes arise under future land-cover and climate change scenarios pointing towards a severe increase in high extremes of flow: the multi-model mean of the 95th percentile of streamflow (Q5) is projected to increase by 63 % under the combined land-use and climate change high emissions scenario (RCP8.5). The changes in all examined hydrological components are greater in the combined land-use and climate change experiment. Results are further presented in a water resources context, aiming to address potential implications of climate change and land-use change from a water demand perspective. We conclude that future water demands in the Upper Ganges region for winter months may not be met.
A novel representation of chalk hydrology in a land surface model
NASA Astrophysics Data System (ADS)
Rahman, Mostaquimur; Rosolem, Rafael
2016-04-01
Unconfined chalk aquifers contain a significant portion of water in the United Kingdom. In order to optimize the assessment and management practices of water resources in the region, modelling and monitoring of soil moisture in the unsaturated zone of the chalk aquifers are of utmost importance. However, efficient simulation of soil moisture in such aquifers is difficult mainly due to the fractured nature of chalk, which creates high-velocity preferential flow paths in the unsaturated zone. In this study, the Joint UK Land Environment Simulator (JULES) is applied on a study area encompassing the Kennet catchment in Southern England. The fluxes and states of the coupled water and energy cycles are simulated for 10 consecutive years (2001-2010). We hypothesize that explicit representation for the soil-chalk layers and the inclusion of preferential flow in the fractured chalk aquifers improves the reproduction of the hydrological processes in JULES. In order to test this hypothesis, we propose a new parametrization for preferential flow in JULES. This parametrization explicitly describes the flow of water in soil matrices and preferential flow paths using a simplified approach which can be beneficial for large-scale hydrometeorological applications. We also define the overlaying soil properties obtained from the Harmonized World Soil Database (HWSD) in the model. Our simulation results are compared across spatial scales with measured soil moisture and river discharge, indicating the importance of accounting for the physical properties of the medium while simulating hydrological processes in the chalk aquifers.
NASA Astrophysics Data System (ADS)
Hayman, Garry; Comyn-Platt, Edward; McNorton, Joey; Chipperfield, Martyn; Gedney, Nicola
2016-04-01
The atmospheric concentration of methane began rising again in 2007 after a period of near-zero growth [1,2], with the largest increases observed over polar northern latitudes and the Southern Hemisphere in 2007 and in the tropics since then. The observed inter-annual variability in atmospheric methane concentrations and the associated changes in growth rates have variously been attributed to changes in different methane sources and sinks [2,3]. Wetlands are generally accepted as being the largest, but least well quantified, single natural source of CH4, with global emission estimates ranging from 142-284 Tg yr-1 [3]. The modelling of wetlands and their associated emissions of CH4 has become the subject of much current interest [4]. We have previously used the HadGEM2 chemistry-climate model to evaluate the wetland emission estimates derived using the UK community land surface model (JULES, the Joint UK Land Earth Simulator) against atmospheric observations of methane, including SCIAMACHY total methane columns [5] up to 2007. We have undertaken a series of new HadGEM2 runs using new JULES emission estimates extended in time to the end of 2012, thereby allowing comparison with both SCIAMACHY and GOSAT atmospheric column methane measurements. We will describe the results of these runs and the implications for methane wetland emissions. References [1] Rigby, M., et al.: Renewed growth of atmospheric methane. Geophys. Res. Lett., 35, L22805, 2008; [2] Nisbet, E.G., et al.: Methane on the Rise-Again, Science 343, 493, 2014; [3] Kirschke, S., et al.,: Three decades of global methane sources and sinks, Nature Geosciences, 6, 813-823, 2013; [4] Melton, J. R., et al.: Present state of global wetland extent and wetland methane modelling: conclusions from a model inter-comparison project (WETCHIMP), Biogeosciences, 10, 753-788, 2013; [5] Hayman, G.D., et al.: Comparison of the HadGEM2 climate-chemistry model against in situ and SCIAMACHY atmospheric methane data, Atmos. Chem. Phys., 14, 13257-13280, 2014.
ComTrustO: Composite Trust-Based Ontology Framework for Information and Decision Fusion
2015-07-06
based definitions and models of trust have been studied in various domains [39]. Jules et al. [27] propose an intelligent and dynamic Service Level...Cognitive and affective trust in service relationships. Journal of Business Research, 58:500–507, 2005. [27] O. Jules , A. Hafid, and M.A. Serhani
Modelling Soil Heat and Water Flow as a Coupled Process in Land Surface Models
NASA Astrophysics Data System (ADS)
García González, Raquel; Verhoef, Anne; Vidale, Pier Luigi; Braud, Isabelle
2010-05-01
To improve model estimates of soil water and heat flow by land surface models (LSMs), in particular in the first few centimetres of the near-surface soil profile, we have to consider in detail all the relevant physical processes involved (see e.g. Milly, 1982). Often, thermal and iso-thermal vapour fluxes in LSMs are neglected and the simplified Richard's equation is used as a result. Vapour transfer may affect the water fluxes and heat transfer in LSMs used for hydrometeorological and climate simulations. Processes occurring in the top 50 cm soil may be relevant for water and heat flux dynamics in the deeper layers, as well as for estimates of evapotranspiration and heterotrophic respiration, or even for climate and weather predictions. Water vapour transfer, which was not incorporated in previous versions of the MOSES/JULES model (Joint UK Land Environment Simulator; Cox et al., 1999), has now been implemented. Furthermore, we also assessed the effect of the soil vertical resolution on the simulated soil moisture and temperature profiles and the effect of the processes occurring at the upper boundary, mainly in terms of infiltration rates and evapotranspiration. SiSPAT (Simple Soil Plant Atmosphere Transfer Model; Braud et al., 1995) was initially used to quantify the changes that we expect to find when we introduce vapour transfer in JULES, involving parameters such as thermal vapour conductivity and diffusivity. Also, this approach allows us to compare JULES to a more complete and complex numerical model. Water vapour flux varied with soil texture, depth and soil moisture content, but overall our results suggested that water vapour fluxes change temperature gradients in the entire soil profile and introduce an overall surface cooling effect. Increasing the resolution smoothed and reduced temperature differences between liquid (L) and liquid/vapour (LV) simulations at all depths, and introduced a temperature increase over the entire soil profile. Thermal gradients rather than soil water potential gradients seem to cause temporal and spatial (vertical) soil temperature variability. We conclude that a multi-soil layer configuration may improve soil water dynamics, heat transfer and coupling of these processes, as well as evapotranspiration estimates and land surface-atmosphere coupling. However, a compromise should be reached between numerical and process-simulation aspects. References: Braud I., A.C. Dantas-Antonino, M. Vauclin, J.L. Thony and P. Ruelle, 1995b: A Simple Soil Plant Atmo- sphere Transfer model (SiSPAT), Development and field verification, J. Hydrol, 166: 213-250 Cox, P.M., R.A. Betts, C.B. Bunton, R.L.H. Essery, P.R. Rowntree, and J. Smith (1999), The impact of new land surface physics on the GCM simulation of climate and climate sensitivity. Clim. Dyn., 15, 183-203. Milly, P.C.D., 1982. Moisture and heat transport in hysteric inhomogeneous porous media: a matric head- based formulation and a numerical model, Water Resour. Res., 18:489-498
2017-08-17
This region on Ceres, located in the vicinity of Toharu Crater, presents two small craters: Juling at top (12 miles, 20 kilometers in diameter) and Kupalo at bottom (16 miles, 26 kilometers in diameter). Both craters are relatively young, as indicated by their sharp rims. These features are located at about the same latitude (about 38 degrees south) as Tawals Crater and show similar crater shapes and rugged terrain. These features may reflect the presence of ice below the surface. Subtle bright features can be distinguished in places. These likely were excavated by small impacts and landslides along the slopes of the crater rims. This suggests that a different type of material, likely rich in salts, is present in the shallow subsurface. Juling is named after the Sakai/Orang Asli spirit of the crops from Malaysia, and Kupalo gets its name from the Russian god of vegetation and of the harvest. NASA's Dawn spacecraft acquired this picture on August 24, 2016. The image was taken during Dawn's extended mission, from its low altitude mapping orbit at about 240 miles (385 kilometers) above the surface. The center coordinates of this image are 38 degrees south latitude, 165 degrees east longitude. https://photojournal.jpl.nasa.gov/catalog/PIA21753
2017-08-25
This high-resolution image of Juling Crater on Ceres reveals, in exquisite detail, features on the rims and crater floor. The crater is about 1.6 miles (2.5 kilometers) deep and the small mountain, seen left of the center of the crater, is about 0.6 miles (1 kilometers) high. The many features indicative of the flow of material suggest the subsurface is rich in ice. The geological structure of this region also generally suggests that ice is involved. The origin of the small depression seen at the top of the mountain is not fully understood but might have formed as a consequence of a landslide, visible on the northeastern flank. Dawn took this image during its extended mission on August 25, 2016, from its low-altitude mapping orbit at a distance of about 240 miles (385 kilometers) above the surface. The center coordinates of this image are 36 degrees south latitude, 167 degrees east longitude. Juling is named after the Sakai/Orang Asli spirit of the crops from Malaysia. NASA's Dawn spacecraft acquired this picture on August 24, 2016. The image was taken during Dawn's extended mission, from its low altitude mapping orbit at about 240 miles (385 kilometers) above the surface. The center coordinates of this image are 38 degrees south latitude, 165 degrees east longitude. https://photojournal.jpl.nasa.gov/catalog/PIA21754
A novel representation of groundwater dynamics in large-scale land surface modelling
NASA Astrophysics Data System (ADS)
Rahman, Mostaquimur; Rosolem, Rafael; Kollet, Stefan
2017-04-01
Land surface processes are connected to groundwater dynamics via shallow soil moisture. For example, groundwater affects evapotranspiration (by influencing the variability of soil moisture) and runoff generation mechanisms. However, contemporary Land Surface Models (LSM) generally consider isolated soil columns and free drainage lower boundary condition for simulating hydrology. This is mainly due to the fact that incorporating detailed groundwater dynamics in LSMs usually requires considerable computing resources, especially for large-scale applications (e.g., continental to global). Yet, these simplifications undermine the potential effect of groundwater dynamics on land surface mass and energy fluxes. In this study, we present a novel approach of representing high-resolution groundwater dynamics in LSMs that is computationally efficient for large-scale applications. This new parameterization is incorporated in the Joint UK Land Environment Simulator (JULES) and tested at the continental-scale.
Wetland methane modelling over the Scandinavian Arctic: Performance of current land-surface models
NASA Astrophysics Data System (ADS)
Hayman, Garry; Quiquet, Aurélien; Gedney, Nicola; Clark, Douglas; Friend, Andrew; George, Charles; Prigent, Catherine
2014-05-01
Wetlands are generally accepted as being the largest, but least well quantified, single natural source of CH4, with global emission estimates ranging from 100-231 Tg yr-1 [1] and for which the Boreal and Arctic regions make a significant contribution [2, 3]. The recent review by Melton et al. [4] has provided a summary of the current state of knowledge on the modelling of wetlands and the outcome of the WETCHIMP model intercomparison exercise. Melton et al. found a large variation in the wetland areas and associated methane emissions from the participating models and varying responses to climate change. In this paper, we report results from offline runs of two land surface models over Scandinavia (JULES, the Joint UK Land Environment Simulator [5, 6] and HYBRID8 [7]), using the same driving meteorological dataset (CRU-NCEP) for the period from January 1980 to December 2010. Although the two land surface models are very different, both models have used a TOPMODEL approach to derive the wetland area and have similar parameterisations of the methane wetland emissions. We find that both models give broadly similar results. They underestimate the wetland areas over Northern Scandinavia, compared to remote sensing and map-based datasets of wetlands [8]. This leads to lower predicted methane emissions compared to those observed on the ground and from aircraft [9]. We will present these findings and identify possible reasons for the underprediction. We will show the sensitivity to using the observed wetland areas to improve the methane emission estimates. References [1] Denman, K., et al.,: Couplings Between Changes in the Climate System and Biogeochemistry, In Climate Change 2007: The Physical Science Basis, Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press, United Kingdom, 2007; [2] Smith, L. C., et al.: Siberian peatlands a net carbon sink and global methane source since the early Holocene, Science, 303, 353-356, doi:10.1126/science.1090553, 2004; [3] Zhuang, Q., et al.: CO2 and CH4 exchanges between land ecosystems and the atmosphere in northern high latitudes over the 21st century, Geophysical Research Letters, 33, doi:10.1029/2006gl026972, 2006; [4] Melton, J.R., et al.: Present state of global wetland extent and wetland methane modelling: conclusions from a model inter-comparison project (WETCHIMP), Biogeosciences, 10, 753-788, doi:10.5194/bg-10-753-2013, 2013; [5] Best, M. J., et al.: The Joint UK Land Environment Simulator (JULES), model description - Part 1: Energy and water fluxes, Geoscientific Model Development, 4, 677-699, doi:10.5194/gmd-4-677-2011, 2011; [6] Clark, D.B., et al.: The Joint UK Land Environment Simulator (JULES), Model description - Part 2: Carbon fluxes and vegetation. Geoscientific Model Development, 4, 701-722, doi:10.5194/gmd-4-701-2011, 2011; [7] Friend, A.D., and N.Y. Kiang: Land surface model development for the GISS GCM: Effects of improved canopy physiology on simulated climate. J. Climate, 18, 2883-2902, doi:10.1175/JCLI3425.1, 2005; [8] Prigent, C., et al.: Changes in land surface water dynamics since the 1990s and relation to population pressure, Geophys. Res. Lett., 39, L08403, doi:10.1029/2012GL051276, 2012; [9] O'Shea, S., et al.: Methane and carbon dioxide fluxes from the European Arctic wetlands during the MAMM project, paper in preparation.
2016-02-23
This image of Ceres from NASA Dawn spacecraft was taken at an oblique viewing angle relative to the surface. The crater to the upper right is named Juling which displays prominent spurs of compacted material along its walls.
Simulation of infiltration and redistribution of intense rainfall using Land Surface Models
NASA Astrophysics Data System (ADS)
Mueller, Anna; Verhoef, Anne; Cloke, Hannah
2016-04-01
Flooding from intense rainfall (FFIR) can cause widespread damage and disruption. Numerical Weather Prediction (NWP) models provide distributed information about atmospheric conditions, such as precipitation, that can lead to a flooding event. Short duration, high intensity rainfall events are generally poorly predicted by NWP models, because of the high spatiotemporal resolution required and because of the way the convective rainfall is described in the model. The resolution of NWP models is ever increasing. Better understanding of complex hydrological processes and the effect of scale is important in order to improve the prediction of magnitude and duration of such events, in the context of disaster management. Working as part of the NERC SINATRA project, we evaluated how the Land Surface Model (LSM) components of NWP models cope with high intensity rainfall input and subsequent infiltration problems. Both in terms of the amount of water infiltrated in the soil store, as well as the timing and the amount of surface and subsurface runoff generated. The models investigated are SWAP (Soil Water Air Plant, Alterra, the Netherlands, van Dam 1997), JULES (Joint UK Land Environment Simulator a component of Unified Model in UK Met Office, Best et al. 2011) and CHTESSEL (Carbon and Hydrology- Tiled ECMWF Scheme for Surface Exchanges over Land, Balsamo et al. 2009) We analysed the numerical aspects arising from discontinuities (or sharp gradients) in forcing and/or the model solution. These types of infiltration configurations were tested in the laboratory (Vachaud 1971), for some there are semi-analytical solutions (Philip 1957, Parlange 1972, Vanderborght 2005) or reference numerical solutions (Haverkamp 1977, van Dam 2000, Vanderborght 2005). The maximum infiltration by the surface, Imax, is in general dependent on atmospheric conditions, surface type, soil type, soil moisture content θ, and surface orographic factor σ. The models used differ in their approach to describe and deal with this top boundary condition definition. All three LSMs discretise the spatial derivative in the Richards equation (∂/∂z) using central finite differences, which is a 2nd order method, that according to Godunov's theorem is non-monotone. It is prone to producing non-physical oscillations in the solution. We performed a mesh and timestep dependence study for hypothetical soil columns and showed the presence of the oscillations in Jules and SWAP solutions. We also investigated the rainfall/runoff partition and redistribution in case of intense rainfall using these three models.
Jules Stein, MD: Ophthalmologist, Entertainment Magnate, and Advocate for Vision.
Straatsma, Bradley R; Weeks, David F
2016-04-01
To report the lifetime activities and accomplishments of Jules Stein, MD. Retrospective review. Assessment of published and unpublished biographical material. Jules Stein combined his love of music and medicine with organizational skills to achieve successive careers as a musician, an ophthalmologist, an entertainment magnate, and an advocate for vision. To preserve vision, he founded Research to Prevent Blindness, founded the Jules Stein Eye Institute at the University of California, Los Angeles, and led a multiyear campaign to establish the National Eye Institute. With successive careers and extraordinary achievements, Jules Stein created an enduring legacy of benefits to ophthalmology, vision research, and the prevention of blindness. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Harper, Anna B.; Cox, Peter M.; Friedlingstein, Pierre; Wiltshire, Andy J.; Jones, Chris D.; Sitch, Stephen; Mercado, Lina M.; Groenendijk, Margriet; Robertson, Eddy; Kattge, Jens; Bönisch, Gerhard; Atkin, Owen K.; Bahn, Michael; Cornelissen, Johannes; Niinemets, Ülo; Onipchenko, Vladimir; Peñuelas, Josep; Poorter, Lourens; Reich, Peter B.; Soudzilovskaia, Nadjeda A.; van Bodegom, Peter
2016-07-01
Dynamic global vegetation models are used to predict the response of vegetation to climate change. They are essential for planning ecosystem management, understanding carbon cycle-climate feedbacks, and evaluating the potential impacts of climate change on global ecosystems. JULES (the Joint UK Land Environment Simulator) represents terrestrial processes in the UK Hadley Centre family of models and in the first generation UK Earth System Model. Previously, JULES represented five plant functional types (PFTs): broadleaf trees, needle-leaf trees, C3 and C4 grasses, and shrubs. This study addresses three developments in JULES. First, trees and shrubs were split into deciduous and evergreen PFTs to better represent the range of leaf life spans and metabolic capacities that exists in nature. Second, we distinguished between temperate and tropical broadleaf evergreen trees. These first two changes result in a new set of nine PFTs: tropical and temperate broadleaf evergreen trees, broadleaf deciduous trees, needle-leaf evergreen and deciduous trees, C3 and C4 grasses, and evergreen and deciduous shrubs. Third, using data from the TRY database, we updated the relationship between leaf nitrogen and the maximum rate of carboxylation of Rubisco (Vcmax), and updated the leaf turnover and growth rates to include a trade-off between leaf life span and leaf mass per unit area.Overall, the simulation of gross and net primary productivity (GPP and NPP, respectively) is improved with the nine PFTs when compared to FLUXNET sites, a global GPP data set based on FLUXNET, and MODIS NPP. Compared to the standard five PFTs, the new nine PFTs simulate a higher GPP and NPP, with the exception of C3 grasses in cold environments and C4 grasses that were previously over-productive. On a biome scale, GPP is improved for all eight biomes evaluated and NPP is improved for most biomes - the exceptions being the tropical forests, savannahs, and extratropical mixed forests where simulated NPP is too high. With the new PFTs, the global present-day GPP and NPP are 128 and 62 Pg C year-1, respectively. We conclude that the inclusion of trait-based data and the evergreen/deciduous distinction has substantially improved productivity fluxes in JULES, in particular the representation of GPP. These developments increase the realism of JULES, enabling higher confidence in simulations of vegetation dynamics and carbon storage.
NASA Astrophysics Data System (ADS)
The Department of Meteorology and Physical Oceanography at the Massachusetts Institute of Technology has established a fund in honor of the late Jule G. Charney. Charney died in Boston last month (Eos, July 7). Income from the fund will be awarded to meritorious students for graduate study in the department. The awards will be known as the Jule G. Charney Awards.
Volff, J N; Körting, C; Altschmied, J; Duschl, J; Sweeney, K; Wichert, K; Froschauer, A; Schartl, M
2001-02-01
Jule is the second complete long-terminal-repeat (LTR) Ty3/Gypsy retrotransposon identified to date in vertebrates. Jule, first isolated from the poeciliid fish Xiphophorus maculatus, is 4.8 kb in length, is flanked by two 202-bp LTRs, and encodes Gag (structural core protein) and Pol (protease, reverse transcriptase, RNase H, and integrase, in that order) but no envelope. There are three to four copies of Jule per haploid genome in X. maculatus. Two of them are located in a subtelomeric region of the sex chromosomes, where they are associated with the Xmrk receptor tyrosine kinase genes, of which oncogenic versions are responsible for the formation of hereditary melanoma in Xiphophorus. One almost intact copy of Jule was found in the first intron of the X-chromosomal allele of the Xmrk proto-oncogene, and a second, more corrupted copy is present only 56 nt downstream of the polyadenylation signal of the Xmrk oncogene. Jule-related elements were detected by Southern blot hybridization with less than 10 copies per haploid genome in numerous other poeciliids, as well as in more divergent fishes, including the medakafish Oryzias latipes and the tilapia Oreochromis niloticus. Database searches also identified Jule-related sequences in the zebrafish Danio rerio and in both genome project pufferfishes, Fugu rubripes and Tetraodon nigroviridis. Phylogenetic analysis revealed that Jule is the first member of the Mag family of Ty3/Gypsy retrotransposons described to date in vertebrates. This family includes the silkworm Mag and sea urchin SURL retrotransposons, as well as sequences from the nematode Caenorhabditis elegans. Additional related elements were identified in the genomes of the malaria mosquito Anopheles gambiae and the nematode Ascaris lumbricoides. Phylogeny of Mag-related elements suggested that the Mag family of retrotransposons is polyphyletic and is constituted of several ancient lineages that diverged before their host genomes more than 600 MYA.
Photosynthesis sensitivity to climate change in land surface models
NASA Astrophysics Data System (ADS)
Manrique-Sunen, Andrea; Black, Emily; Verhoef, Anne; Balsamo, Gianpaolo
2016-04-01
Accurate representation of vegetation processes within land surface models is key to reproducing surface carbon, water and energy fluxes. Photosynthesis determines the amount of CO2 fixated by plants as well as the water lost in transpiration through the stomata. Photosynthesis is calculated in land surface models using empirical equations based on plant physiological research. It is assumed that CO2 assimilation is either CO2 -limited, radiation -limited ; and in some models export-limited (the speed at which the products of photosynthesis are used by the plant) . Increased levels of atmospheric CO2 concentration tend to enhance photosynthetic activity, but the effectiveness of this fertilization effect is regulated by environmental conditions and the limiting factor in the photosynthesis reaction. The photosynthesis schemes at the 'leaf level' used by land surface models JULES and CTESSEL have been evaluated against field photosynthesis observations. Also, the response of photosynthesis to radiation, atmospheric CO2 and temperature has been analysed for each model, as this is key to understanding the vegetation response that climate models using these schemes are able to reproduce. Particular emphasis is put on the limiting factor as conditions vary. It is found that while at present day CO2 concentrations export-limitation is only relevant at low temperatures, as CO2 levels rise it becomes an increasingly important restriction on photosynthesis.
NASA Astrophysics Data System (ADS)
Spessa, Allan; Fisher, Rosie
2010-05-01
Tropical savannas cover 18% of the world's land surface and are amongst the most productive terrestrial systems in the world. They comprise 15% of the total terrestrial carbon stock, with an estimated mean net primary productivity (NPP) of 7.2 tCha-1yr-1 or two thirds of NPP in tropical forests. Tropical savannas are the most frequently burnt biome, with fire return intervals in highly productive areas being typically 1-2 years. Fires shape vegetation species composition, tree to grass ratios and nutrient redistribution, as well as the biosphere-atmosphere exchange of trace gases, momentum and radiative energy. Tropical savannas are a major source of emissions, contributing 38 % of total annual CO2 from biomass burning, 30% CO, 19 % CH4 and 59 % NOx. Climatically, they occur in regions subject to a strongly seasonal ‘wet-dry' regime, usually under monsoonal control from the movement of the inter-tropical convergence zone. In general, rainfall during the prior wet season(s) determines the amount of grass fuel available for burning while the length of the dry season influences fuel moisture content. Rainfall in tropical savannas exhibits high inter-annual variability, and under future climate change, is projected to change significantly in much of Africa, South America and northern Australia. Process-based simulation models of fire-vegetation dynamics and feedbacks are critical for determining the impacts of wildfires under projected future climate change on i) ecosystem structure and function, and ii) emissions of trace gases and aerosols from biomass burning. A new mechanistic global fire model SPITFIRE (SPread and InTensity of FIRE) has been designed to overcome many of the limitations in existing fire models set within Dynamic Global Vegetation Models (DGVMs). SPITFIRE has been applied in coupled mode globally and southern Africa, both as part of the LPJ DGVM. It has also been driven with MODIS burnt area data applied to sub-Saharan Africa, while coupled to the LPJ-GUESS vegetation model. Recently, SPIFTIRE has been coupled to the Ecosystem Demography (ED) model, which simulates global vegetation dynamics as part of the new land surface scheme JULES (Joint UK Environment Simulator) within the QUEST Earth System Model (http://www.quest-esm.ac.uk/). This study forms part of on-going work to further improve and test the ability of JULES to accurately simulate the terrestrial carbon cycle and land-atmosphere exchanges under different climates. Using the JULES (ED-SPITFIRE) model driven by observed climate (1901-2002), and focusing on large-scale rainfall gradients in the tropical savannas of west Africa, the Northern Territory (Australia) and central-southern Brazil, this study assesses: i) simulated versus observed vegetation dynamics and distributions, and ii) the relative importance of fire versus rainfall in determining vegetation patterns. A sensitivity analysis approach was used.
NASA Astrophysics Data System (ADS)
Tanguy, Maliko
The objective of the thesis is to develop and evaluate useful tools and applications of Earth Observation (EO) satellite data to estimate surface fluxes in semi-arid countries. In a first part (Chapter 4), we assess the performance of a new parameterisation scheme of ground heat flux (G) to be used in remote sensing (RS) evapotranspiration (ET) estimation methods. The G-parameterisation optimized with AMMA flux data performs well and improves the sensible heat flux (H) and ET retrieved by means of the triangle method (Jiang & Islam, 2001). In a second part (Chapter 5), the triangle method is compared with ET estimated by means of a land surface model (JULES). An attempt is made to calibrate JULES using the triangle method through Monte Carlo simulations, but the two methods supply rather different results, indicating that further intercomparison tasks should be carried out to assess the performance of RS-based algorithms and land surface models in estimating the components of the land surface energy balance. Chapter 6 presents a set of operational examples for retrieving surface fluxes using RS data. The first example is the study of temporal evolution of ET-maps in Western Africa under monsoonal influence. In a second example, we apply the new scheme proposed in Chapter 4 to retrieve and analyse the long term evolution (2000-2009) of the surface energy balance components, G, H and ET at several sites of the Segura Basin (S-E Spain) using MODIS-Terra data (land surface temperature and NDVI). Temporal and spatial distribution of evapotranspiration reveals different controls on ET. (Chapter 6). In the last example, MODIS-Aqua Sea Surface Temperature (SST) is used to validate a mathematical model to retrieve surface fluxes in a Mediterranean coastal lagoon (Mar Menor, S-E Spain). El objetivo de esta tesis es de desarrollar y evaluar herramientas y aplicaciones de la teledetección para estimar flujos de superficie en zonas semiáridas. En una primera parte (Capítulo 4), se evalúa la fiabilidad de una nueva parametrización para estimar el flujo de calor en el suelo (G) con el fin de ser utilizado en métodos de estimación de la evapotranspiración (ET) usando datos de teledetección. La parametrización de G se optimiza usando datos de flujo de energía obtenido durante las campañas del proyecto AMMA, y muestra buenos resultados y una mejora de las estimaciones del flujo de calor sensible (H) y de ET cuando se utiliza conjuntamente con el método del triángulo (Jiang & Islam, 2001). En una segunda parte (Capítulo 5), el método del triángulo se compara con valores de ET estimado por un modelo de superficie terrestre (JULES). Se intenta calibrar JULES usando el método del triángulo mediante simulaciones de Monte Carlo, pero los dos métodos muestran resultados muy diferentes, indicando que se necesita tareas de comparación profundizadas para poder evaluar la eficacia de estos modelos (de superficie terrestre y basados en la teledetección) para estimar los flujos de energía a la superficie. El capítulo 6 presenta un conjunto de ejemplos de aplicaciones operacionales para estimar los flujos de superficie usando datos de teledetección. El primer ejemplo consiste en el estudio de la evolución temporal de mapas de ET en África occidental bajo la influencia del monzón africano. En el segundo ejemplo, se aplica la nueva parametrización de G descrita en el capítulo 4 para calcular y analizar la evolución a largo plazo (2000-2009) de los componentes del balance de energía a la superficie, G, H y ET, en diferentes puntos de la cuenca del río Segura (Sureste español) utilizando datos del sensor MODIS-Terra (temperatura superficial y NDVI). La distribución temporal y espacial de ET revela diferentes controles sobre ET. En el último ejemplo, datos de temperatura superficial del mar del sensor MODIS-Aqua se utilizaron para validar un modelo matemático para calcular los flujos superficiales de una laguna costera del Mediterráneo (Mar Menor en el Sureste español).
NASA Astrophysics Data System (ADS)
Wilebore, Beccy; Willis, Kathy
2016-04-01
Landcover conversion is one of the largest anthropogenic threats to ecological services globally; in the EU around 1500 ha of biodiverse land are lost every day to changes in infrastructure and urbanisation. This land conversion directly affects key ecosystem services that support natural infrastructure, including water flow regulation and the mitigation of flood risks. We assess the sensitivity of runoff production to landcover in the UK at a high spatial resolution, using a distributed hydrologic model in the regional land-surface model JULES (Joint UK Land Environment Simulator). This work, as part of the wider initiative 'NaturEtrade', will create a novel suite of easy-to-use tools and mechanisms to allow EU landowners to quickly map and assess the value of their land in providing key ecosystem services.
Issues in Big-Data Database Systems
2014-06-01
Post, 18 August 2013. Berman, Jules K. (2013). Principles of Big Data: Preparing, Sharing, and Analyzing Complex Information. New York: Elsevier... Jules K. (2013). Principles of Big Data: Preparing, Sharing, and Analyzing Complex Information. New York: Elsevier. 261pp. Characterization of
Charney's Influence on Modern Oceanography
NASA Astrophysics Data System (ADS)
Cane, M. A.
2017-12-01
In this talk I will review some of Jule Charney's impacts on current oceanographic research. He was of course a major seminal figure in geophysical fluid dynamics, an approach to understanding the atmosphere and oceans that has been thoroughly absorbed in contemporary thinking. In oceanography, his publications make vorticity dynamics the centerpiece of his analysis. Here I pursue two other aspects of his work. The first is to note that his 1955 paper "The Gulf Stream as an inertial boundary layer" appears to be the earliest numerical model in oceanography. The second is that his work on the equatorial undercurrent leads to a simplification of equatorial ocean structure that was exploited by Zebiak and Cane in their model for ENSO, and thus structures later views of how equatorial ocean dynamics influence sea surface temperature.
Geophysicists: Jules Aarons (1921-2008)
NASA Astrophysics Data System (ADS)
Mendillo, Michael
2009-03-01
Jules Aarons, a pioneer in satellite radio beacon studies of the ionosphere, died peacefully at his home in Newton, Mass., on 21 November 2008 at age 87. When considering his college career, Jules was drawn toward the humanities, an interest subsequently redirected by his parents toward science as a more suitable way to earn a living, and then by the U.S. Army Air Corps toward radio technology as a more suitable way to win World War II. Both goals were readily accomplished, perhaps instilling in Jules the value of proper mentorship, that central aspect of his life that so dominates our recollections of him. After the war, and with a variety of options before him, Jules decided upon civilian government service at the U.S. Air Force's then new field station in Cambridge, Mass. This was the founding entity of the Air Force Cambridge Research Laboratory (AFCRL), and those five famous letters became identified with his professional career (1946-1981). With Russia's launch of Sputnik in 1957, the era of space-based radio communications began, and with it the need to understand the sporadic crackling and fading (``scintillations'') of radio transmissions from satellites to ground receiving stations. Wartime efforts also gave birth to radio astronomy. Jules fostered ways to fund the synergies he saw between the radio technologies of space science and those of ground-based radio astronomy in ways almost unimaginable today (and certainly not by former U.S. senator Mike Mansfield, whose 1973 amendment to the U.S. Congress's defense appropriations bill limited the financing of basic research by military agencies only to projects that have direct military consequences; the amendment resulted in a permanent restructuring of how U.S. Department of Defense (DOD) agencies fund university-based research).
2018-06-05
This image of Juling and Kupalo Craters was obtained by NASA's Dawn spacecraft on May 25, 2018 from an altitude of about 855 miles (1380 kilometers). The center coordinates of this image are about 38 degrees south in latitude and 173 degrees east in longitude. https://photojournal.jpl.nasa.gov/catalog/PIA22470
Lifting Off of the Digital Plateau with Military Decision Support Systems
2013-05-23
concerns were echoed in Germany, where Colonel (later General) Jules von Verdy stripped away the complex rules and tables, and relied on the military...Review (March-April 2001): 38-45. 55 Swift, Eben. Orders. Fort Leavenworth: Staff College Press, 1905. Verdy, Jules von. Free Kreigspiel. Edited by
2018-03-14
This view from NASA's Dawn mission shows the floor of Ceres' Juling Crater. The crater floor shows evidence of the flow of ice and rock, similar to rock glaciers in Earth's polar regions. Dawn acquired the picture with its framing camera on Aug. 30, 2016. https://photojournal.jpl.nasa.gov/catalog/PIA21920
Finite Element Analysis and Experimentation of an Icosahedron Frame under Compression
2015-09-17
Century of Flight. Jules Henri Gi_ard (1825 - 1882), January 2014. URL [Online]. Available: http://www.century-of-flight.net/Aviation%20history/to...20reality/ Jules % 20Henri%20Gi_ard.htm. [4] Compression test. [Online]. Available: http://en.wikipedia.org/wiki/Compressive_strength [5
NASA Astrophysics Data System (ADS)
Nicholson, S. E.
2013-12-01
The paper provides an historical review of research on the impact of the land surface on climate. It commences will the seminal work of Jule Charney on albedo as a potential cause of drought and follows the trail of follow-up studies on the question of desertification and its role in climate. With the exception of a very early paper by Namias, early work was limited mainly to modeling efforts. At the same time, several observational studies provided evidence that land surface feedbacks could enhance and prolong drought, especially in the African Sahel. Later work emphasized the role of soil moisture rather than albedo. Several important field studies also examined the role of the land surface. Examples include FIFE, HAPEX-Sahel and BOREAS. In recent years some major changes in the concept have occurred. There is now substantial observational evidence of an impact at the mesoscale. The role of land surface feedback on climate has become mainstream. Finally, a new subdiscipline has emerged that emphasizes feedbacks between the water cycle, vegetation and climate, namely ecohydrology.
Would Jule Charney Have Cracked the Madden-Julian Oscillation?
NASA Astrophysics Data System (ADS)
Emanuel, K.
2017-12-01
Jule Charney's approach to science often involved looking at old problems in new ways. One example was his theory of baroclinic instability, which followed on the heels of long-standing efforts to explain well-observed cyclones and anticyclones. He mastered the art of boiling a physical phenomenon down to its essence, throwing away many things that others had considered important while expressing that which he retained in the simplest possible way. To help honor Charney's legacy, I will review the history of another well-observed phenomenon - the Madden Julian Oscillation (MJO) - together with the many largely unsuccessful efforts to explain it, culminating finally in a satisfying explanation that Jule would have loved.
On the Verbal Art of a Modern Painter: The Work of Jules Kirschenbaum.
ERIC Educational Resources Information Center
Gandelman, Claude
1989-01-01
Notes that Jules Kirschenbaum, a modern American artist whose work integrates inscriptions and figurative painting, studied under the masters of abstract expressionism yet exhibited with protagonists of "magic realism." States that his later work took a wholly different turn--it became art about meaning and the "meaning of…
NASA Astrophysics Data System (ADS)
Ekici, A.; Chadburn, S.; Chaudhary, N.; Hajdu, L. H.; Marmy, A.; Peng, S.; Boike, J.; Burke, E.; Friend, A. D.; Hauck, C.; Krinner, G.; Langer, M.; Miller, P. A.; Beer, C.
2015-07-01
Modeling soil thermal dynamics at high latitudes and altitudes requires representations of physical processes such as snow insulation, soil freezing and thawing and subsurface conditions like soil water/ice content and soil texture. We have compared six different land models: JSBACH, ORCHIDEE, JULES, COUP, HYBRID8 and LPJ-GUESS, at four different sites with distinct cold region landscape types, to identify the importance of physical processes in capturing observed temperature dynamics in soils. The sites include alpine, high Arctic, wet polygonal tundra and non-permafrost Arctic, thus showing how a range of models can represent distinct soil temperature regimes. For all sites, snow insulation is of major importance for estimating topsoil conditions. However, soil physics is essential for the subsoil temperature dynamics and thus the active layer thicknesses. This analysis shows that land models need more realistic surface processes, such as detailed snow dynamics and moss cover with changing thickness and wetness, along with better representations of subsoil thermal dynamics.
Discover Paris with Jules Verne.
ERIC Educational Resources Information Center
Hudson, Anna E.
1996-01-01
An approach to teaching French literature that uses a Jules Verne novel published only in 1994 is described. The novel, "Paris in the 20th Century," is the basis for a series of written and oral exercises about the novel, its social and cultural context, the author, and the actual changes that have occurred in Paris in comparison with…
A two stream radiative transfer model for scaling solar induced fluorescence from leaf to canopy
NASA Astrophysics Data System (ADS)
Quaife, T. L.
2017-12-01
Solar induced fluorescence (SIF) is becoming widely used as a proxy for gross primary productivity (GPP), in particular with the advent of its measurement by Earth Observation satellites such as OCO and GOSAT. A major attraction of SIF is that it is independent of the assumptions embedded in light use efficiency based GPP products derived from satellite missions such as MODIS. The assumptions in such products are likely not compatible with any given land surface model and hence comparing the two is problematic. On the other hand to compare land surface model predictions of GPP to satellite based SIF data requires either (a) translation of SIF into estimates of GPP, or (b) direct predictions of SIF from the land surface model itself. The former typically relies on empirical relationships, whereas the latter can make direct use of our physiological understanding of the link between photosynthesis and fluorescence at the leaf scale and is therefore preferable. Here I derive a two stream model for fluorescence that is capable of translating between leaf scale models of SIF and the canopy leaving radiance taking into account all levels of photon scattering. Other such models have been developed previously but the model described here is physically consistent with the Sellers' two stream radiative transfer scheme which is widely used in modern land surface models. Consequently any model that already employs the Sellers's scheme can use the new model without requiring modification. This includes, for example, JULES, the land surface model of the new UK Earth System Model (UKESM) and CLM, the US Community Land Model (part of the NCAR Earth System Model). The new canopy SIF model is extremely computationally efficient and can be applied to vertically inhomogeneous canopies.
2018-03-14
This view from NASA's Dawn mission shows where ice has been detected in the northern wall of Ceres' Juling Crater, which is in almost permanent shadow. Dawn acquired the picture with its framing camera on Aug. 30, 2016, and it was processed with the help of NASA Ames Stereo Pipeline (ASP), to estimate the slope of the cliff. https://photojournal.jpl.nasa.gov/catalog/PIA21918
ERIC Educational Resources Information Center
Hendrick, Robert M.
1992-01-01
Examines one of the key methods used to stimulate bourgeois interest in science in France during the Second Empire and early Third Republic; the campaign to create a popularized science. Concentrates on the "science writings" of Jules Michelet and Jules Verne, both of whom were immensely successful in creating a favorable climate of…
Diagnostic and model dependent uncertainty of simulated Tibetan permafrost area
NASA Astrophysics Data System (ADS)
Wang, W.; Rinke, A.; Moore, J. C.; Cui, X.; Ji, D.; Li, Q.; Zhang, N.; Wang, C.; Zhang, S.; Lawrence, D. M.; McGuire, A. D.; Zhang, W.; Delire, C.; Koven, C.; Saito, K.; MacDougall, A.; Burke, E.; Decharme, B.
2015-03-01
We perform a land surface model intercomparison to investigate how the simulation of permafrost area on the Tibetan Plateau (TP) varies between 6 modern stand-alone land surface models (CLM4.5, CoLM, ISBA, JULES, LPJ-GUESS, UVic). We also examine the variability in simulated permafrost area and distribution introduced by 5 different methods of diagnosing permafrost (from modeled monthly ground temperature, mean annual ground and air temperatures, air and surface frost indexes). There is good agreement (99-135 x 104 km2) between the two diagnostic methods based on air temperature which are also consistent with the best current observation-based estimate of actual permafrost area (101 x 104 km2). However the uncertainty (1-128 x 104 km2) using the three methods that require simulation of ground temperature is much greater. Moreover simulated permafrost distribution on TP is generally only fair to poor for these three methods (diagnosis of permafrost from monthly, and mean annual ground temperature, and surface frost index), while permafrost distribution using air temperature based methods is generally good. Model evaluation at field sites highlights specific problems in process simulations likely related to soil texture specification and snow cover. Models are particularly poor at simulating permafrost distribution using definition that soil temperature remains at or below 0°C for 24 consecutive months, which requires reliable simulation of both mean annual ground temperatures and seasonal cycle, and hence is relatively demanding. Although models can produce better permafrost maps using mean annual ground temperature and surface frost index, analysis of simulated soil temperature profiles reveals substantial biases. The current generation of land surface models need to reduce biases in simulated soil temperature profiles before reliable contemporary permafrost maps and predictions of changes in permafrost distribution can be made for the Tibetan Plateau.
Model Evaluation with Multi-wavelength Satellite Observations Using a Neural Network
NASA Astrophysics Data System (ADS)
Kolassa, Jana; Jimenez, Carlos; Aires, Filipe
2013-04-01
A methodology has been developed to evaluate fields of modelled parameters against a set of satellite observations. The method employs a Neural Network (NN) to construct a statistical model capturing the relationship between the satellite observations and the parameter from a land surface model, in this case the Soil Moisture (SM). This statistical model is then used to estimate the parameter of interest from the set of satellite observations. These estimates are compared to the modelled parameter in order to detect local deviations indicating a possible problem in the model or in the satellite observations. Several synthetic tests, during which an artificial error was added to the"true" soil moisture fields, showed that the methodology is able to correct the errors (Jimenez et al., submitted, 2012). This evaluation technique is very general and can be applied to any modelled parameter for which sensitive satellite observations are available. The use of NNs simplifies the evaluation of the model against satellite observations and is particularly well-suited to utilize the synergy from the observations at different wavelengths (Aires et al., 2005, 2012). In this study the proposed methodology has been applied to evaluate SM fields from a number of land surface models against a synergy of satellite observations from passive and active microwave, infrared and visible sensors. In an inter-comparison of the performance of several land surface models (ORCHIDEE (de Rosnay et al., 2002), HTESSEL (Balsamo et al., 2009), JULES (Best et al., 2011) ) it was found that the soil moisture fields from JULES, HTESSEL and ORCHIDEE are very consistent with the observations, but ORCHIDEE soil moisture shows larger local deviations close to some river basins (Kolassa et al., in press, 2012; Jimenez et al., submitted, 2012). Differences between all models and the observations could also be observed in the Eastern US and over mountainous regions, however, the errors here are more likely linked to the retrieved SM uncertainties. The proposed methodology can also be used to evaluate the quality of the model forcings: two soil moisture fields from ORCHIDEE using WATCH (Weedon et al., 2011) and ERA-interim (Balsamo et al., 2010) forcings were analysed. It was shown that the WATCH forcing data are more optimal, underlining the importance of forcing data for the accuracy of model predictions (Kolassa et al., in press, 2012). References Aires, F., Prigent, C., and Rossow, W.B. (2005), Sensitivity of satellite microwave and infrared observations to soil moisture at a global scale: 2. Global statistical relationships, J. Geophys. Res., 110, D11103, doi:10.1029/2004JD005094. Aires, F., O. Aznay, C. Prigent, M. Paul, F. Bernardo, Synergetic multi-wavelegnth remote sensing versus a posteriori combination of retrieved products: Application for the retrieval of atmospheric profiles using MetOp measurements, J. Geophys. Res., 2011 Balsamo, G., Viterbo, P., Beljaars, A., van den Hurk, B., Hirschi, M., Betts, A. and Scipa,l K. (2009) A Revised Hydrology for the ECMWF Model: Verification from Field Site to Terrestrial Water Storage and Impact in the Integrated Forecast System, J. Hydrol., 10, 623-643 Balsamo, G., Boussetta, S., Lopez, P., and Ferranti, L. (2010), Evaluation of ERA-Interim and ERA- Interim-GPCP-rescaled precipitation over the U.S.A., ERA-Report Series, 5, pp. 10. Best, M. J., M. Pryor, D. B. Clark, G. G. Rooney, R .L. H. Essery, C. B. Ménard, J. M. Edwards, M. A. Hendry, A. Porson, N. Gedney, L. M. Mercado, S. Sitch, E. Blyth, O. Boucher, P. M. Cox, C. S. B. Grimmond, and R. J. Harding (2011), The Joint UK Land Environment Simulator (JULES), model description - Part 1: Energy and water fluxes, Geosci. Model Dev., 4 Jimenez, C., Clark, D., Kolassa, J., Aires, F., Prigent, C., and Blyth, E. (2012), A joint analysis of modeled soil moisture fields and satellite observations (2012), J. Geophys. Res., Kolassa, J., Aires, F., Polcher, J., Prigent, C., and Pereira, J. (2012), Soil moisture Retrieval from Multi-instrument Observations: Information Content Analysis and Retrieval Methodology (2012), J. Geophys. Res., de Rosnay, P., Polcher, J., Bruen, M., Laval, K. (2002), Impact of a physically based soil water flow and soil-plant interaction representation for modeling large-scale land surface processes, J. Geophys. Res., 107, D11, 4118, 10.1029/2001JD000634 Weedon, G.P., Gomes, S., Viterbo, P., Shuttleworth, W.J., Blyth, E., O ̈sterle, H., Adam, J.C., Bellouin, N., Boucher, O., and Best, M. (2011), Creation of the WATCH Forcing Data and its use to assess global and regional reference crop evaporation over land during the twentieth century, J. Hydrometeorology,12, 5, pp. 823-848.
Jules Verne Voyager, Jr: An Interactive Map Tool for Teaching Plate Tectonics
NASA Astrophysics Data System (ADS)
Hamburger, M. W.; Meertens, C. M.
2010-12-01
We present an interactive, web-based map utility that can make new geological and geophysical results accessible to a large number and variety of users. The tool provides a user-friendly interface that allows users to access a variety of maps, satellite images, and geophysical data at a range of spatial scales. The map tool, dubbed 'Jules Verne Voyager, Jr.', allows users to interactively create maps of a variety of study areas around the world. The utility was developed in collaboration with the UNAVCO Consortium for study of global-scale tectonic processes. Users can choose from a variety of base maps (including "Face of the Earth" and "Earth at Night" satellite imagery mosaics, global topography, geoid, sea-floor age, strain rate and seismic hazard maps, and others), add a number of geographic and geophysical overlays (coastlines, political boundaries, rivers and lakes, earthquake and volcano locations, stress axes, etc.), and then superimpose both observed and model velocity vectors representing a compilation of 2933 GPS geodetic measurements from around the world. A remarkable characteristic of the geodetic compilation is that users can select from some 21 plates' frames of reference, allowing a visual representation of both 'absolute' plate motion (in a no-net rotation reference frame) and relative motion along all of the world's plate boundaries. The tool allows users to zoom among at least three map scales. The map tool can be viewed at http://jules.unavco.org/VoyagerJr/Earth. A more detailed version of the map utility, developed in conjunction with the EarthScope initiative, focuses on North America geodynamics, and provides more detailed geophysical and geographic information for the United States, Canada, and Mexico. The ‘EarthScope Voyager’ can be accessed at http://jules.unavco.org/VoyagerJr/EarthScope. Because the system uses pre-constructed gif images and overlays, the system can rapidly create and display maps to a large number of users simultaneously and does not require any special software installation on users' systems. In addition, a javascript-based educational interface, dubbed "Exploring our Dynamic Planet", incorporates the map tool, explanatory material, background scientific material, and curricular activities that encourage users to explore Earth processes using the Jules Verne Voyager, Jr. tool. Exploring our Dynamic Planet can be viewed at http://www.dpc.ucar.edu/VoyagerJr/. Because of its flexibility, the map utilities can be used for hands-on exercises exploring plate interaction in a range of academic settings, from high school science classes to entry-level undergraduate to graduate-level tectonics courses.
ERIC Educational Resources Information Center
Hamblin, Jane A., Ed.
This book was created to honor Jules B. LaPidus, retiring president of the Council of Graduate Education, and to preserve his writings and speeches. The papers and speeches of Part 1 show how the author addressed the topical issues of graduate education, moving from observation to direction on research, funding, and preparation of faculty. Part 2…
Use of the HadGEM2 climate-chemistry model to investigate interannual variability in methane sources
NASA Astrophysics Data System (ADS)
Hayman, Garry; O'Connor, Fiona; Clark, Douglas; Huntingford, Chris; Gedney, Nicola
2013-04-01
The global mean atmospheric concentration of methane (CH4) has more than doubled during the industrial era [1] and now constitutes ? 20% of the anthropogenic climate forcing by greenhouse gases [2]. The globally-averaged CH4 growth rate, derived from surface measurements, has fallen significantly from a high of 16 ppb yr-1 in the late 1970s/early 1980s and was close to zero between 1999 and 2006 [1]. This overall period of declining or low growth was however interspersed with years of positive growth-rate anomalies (e.g., in 1991-1992, 1998-1999 and 2002-2003). Since 2007, renewed growth has been evident [1, 3], with the largest increases observed over polar northern latitudes and the Southern Hemisphere in 2007 and in the tropics in 2008. The observed inter-annual variability in atmospheric methane concentrations and the associated changes in growth rates have variously been attributed to changes in different methane sources and sinks [1, 4]. In this paper, we report results from runs of the HadGEM2 climate-chemistry model [5] using year- and month-specific emission datasets. The HadGEM2 model includes the comprehensive atmospheric chemistry and aerosol package, the UK Chemistry Aerosol community model (UKCA, http://www.ukca.ac.uk/wiki/index.php). The Standard Tropospheric Chemistry scheme was selected for this work. This chemistry scheme simulates the Ox, HOx and NOx chemical cycles and the oxidation of CO, methane, ethane and propane. Year- and month-specific emission datasets were generated for the period from 1997 to 2009 for the emitted species in the chemistry scheme (CH4, CO, NOx, HCHO, C2H6, C3H8, CH3CHO, CH3CHOCH3). The approach adopted varied depending on the source sector: Anthropogenic: The emissions from anthropogenic sources were based on decadal-averaged emission inventories compiled by [6] for the Coupled Carbon Cycle Climate Model Intercomparison Project (C4MIP). These were then used to derive year-specific emission datasets by scaling the emission totals for the different years and source sectors using sector and species-specific scaling factors based on the annual trends given in various EDGAR time series: (a) version 4.2 for all species (except NMVOCs) and version 4.1 for NMVOCs; (b) v3.2. This approach was also applied to the emissions from aviation (only for oxides of nitrogen) and international shipping. Biomass burning: Month-specific emission inventories are available from the Global Fire Emissions Database (GFED, v3.1) for the years 1997 to 2009 [7]. The emissions were rescaled to give the same decadal mean as used in the Hadley Centre's earlier HadGEM2 runs (25 Tg CH4 per annum). Other: Sources such as termites and hydrates for methane were taken from the GEIA website and the dataset of Fung et al. [8]. The datasets contain a single annual cycle, which was assumed to apply for all years. For CH4, there are also emissions from wetlands. These were either based on the dataset of Fung et al. [8] or derived from the JULES (Joint UK Land Earth Simulator) land surface model [9, 10]. The standard version of JULES uses a simple methane wetland emission parameterization, developed and tested by [11] for use at large spatial scales. The surface concentrations from the different model runs have been compared to surface atmospheric CH4 measurements. In addition, growth rates have been derived. These comparisons will be reported and used to assess the contribution of different methane sources to the interannual variations in the methane growth rate. References [1] Dlugokencky, E.J., et al.: Global atmospheric methane: budget, changes and dangers. Philosophical Transactions of the Royal Society A, 369, 2058-2072; doi: 10.1098/rsta.2010.0341, 2011. [2] Forster, P., et al.: Changes in Atmospheric Constituents and in Radiative Forcing. In: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M.Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 2007. [3] Rigby, M., et al.: Renewed growth of atmospheric methane. Geophysical Research Letters, 35, L22805, doi:10.1029/2008GL036037, 2008. [4] Bousquet, P., et al.: Contribution of anthropogenic and natural sources to atmospheric methane variability, Nature, 443, 439-443, doi:10.1038/nature05132, 2006. [5] Collins, W. J., et al.: Development and evaluation of an Earth-System model - HadGEM2, Geoscientific Model Development, 4, 1051-1075, doi:10.5194/gmd-4-1051-2011, 2011. [6] Lamarque, J.-F., et al.: Historical (1850-2000) gridded anthropogenic and biomass burning emissions of reactive gases and aerosols: methodology and application, Atmospheric Chemistry and Physics, 10, 7017-7039, doi:10.5194/acp-10-7017-2010, 2010. [7] van der Werf, G. R., et al.: Global fire emissions and the contribution of deforestation, savanna, forest, agricultural, and peat fires (1997-2009), Atmospheric Chemistry and Physics, 10, 11707-11735, doi:10.5194/acp-10-11707-2010, 2010. [8] Fung, I., et al.: Three-dimensional model synthesis of the Global Methane Cycle. Journal of Geophysical Research, 96, 13,033-13,065, 1991. [9] Best, M. J., et al.: The Joint UK Land Environment Simulator (JULES), model description - Part 1: Energy and water fluxes, Geoscientific Model Development, 4, 677-699, doi:10.5194/gmd-4-677-2011, 2011. [10] Clark, D.B., et al.: The Joint UK Land Environment Simulator (JULES), Model description - Part 2: Carbon fluxes and vegetation. Geoscientific Model Development, 4, 701-722, doi:10.5194/gmd-4-701-2011, 2011. [11] Gedney, N., et al.: Climate feedback from wetland methane emissions. Geophysical Research Letters, 31, L20503, 2004.
NASA Astrophysics Data System (ADS)
Smagorinsky, J.
Twelve years ago, Jule Charney was honored by AGU when he was named the 38th William Bowie medalist for having epitomized the Bowie criteria of outstanding contribution to fundamental geophysics and for unselfish cooperation in research.Fifty years of Bowie awards were celebrated at a Special Session of the AGU Spring Meeting held in Baltimore, Md., in May. It is a very special distinction that AGU has selected Charney, among others, from a truly impressive field of superachievers, as one meriting extended recall of his contributions and his place in history.
[Professor Jules Gavarret (1809-1890) and the application of mathematics and physics to medicine].
Beyneix, A
2001-01-01
Professor Jules Gavarret has undertaken pretigious offices, has accumulated various titles and honours and has left an abundant bibliography about physics and chemistry of life phenomenon. To recount the career of one of the academics who were benefited the traditional medicine of the progress achieved in physical and mathematical sciences give us the opportunity of recalling one of the great Parisian personalities of 19th Century who had not been appreciated for too long.
Diagnostic and model dependent uncertainty of simulated Tibetan permafrost area
Wang, A.; Moore, J.C.; Cui, Xingquan; Ji, D.; Li, Q.; Zhang, N.; Wang, C.; Zhang, S.; Lawrence, D.M.; McGuire, A.D.; Zhang, W.; Delire, C.; Koven, C.; Saito, K.; MacDougall, A.; Burke, E.; Decharme, B.
2016-01-01
We perform a land-surface model intercomparison to investigate how the simulation of permafrost area on the Tibetan Plateau (TP) varies among six modern stand-alone land-surface models (CLM4.5, CoLM, ISBA, JULES, LPJ-GUESS, UVic). We also examine the variability in simulated permafrost area and distribution introduced by five different methods of diagnosing permafrost (from modeled monthly ground temperature, mean annual ground and air temperatures, air and surface frost indexes). There is good agreement (99 to 135 × 104 km2) between the two diagnostic methods based on air temperature which are also consistent with the observation-based estimate of actual permafrost area (101 × 104 km2). However the uncertainty (1 to 128 × 104 km2) using the three methods that require simulation of ground temperature is much greater. Moreover simulated permafrost distribution on the TP is generally only fair to poor for these three methods (diagnosis of permafrost from monthly, and mean annual ground temperature, and surface frost index), while permafrost distribution using air-temperature-based methods is generally good. Model evaluation at field sites highlights specific problems in process simulations likely related to soil texture specification, vegetation types and snow cover. Models are particularly poor at simulating permafrost distribution using the definition that soil temperature remains at or below 0 °C for 24 consecutive months, which requires reliable simulation of both mean annual ground temperatures and seasonal cycle, and hence is relatively demanding. Although models can produce better permafrost maps using mean annual ground temperature and surface frost index, analysis of simulated soil temperature profiles reveals substantial biases. The current generation of land-surface models need to reduce biases in simulated soil temperature profiles before reliable contemporary permafrost maps and predictions of changes in future permafrost distribution can be made for the Tibetan Plateau.
Diagnostic and model dependent uncertainty of simulated Tibetan permafrost area
NASA Astrophysics Data System (ADS)
Wang, W.; Rinke, A.; Moore, J. C.; Cui, X.; Ji, D.; Li, Q.; Zhang, N.; Wang, C.; Zhang, S.; Lawrence, D. M.; McGuire, A. D.; Zhang, W.; Delire, C.; Koven, C.; Saito, K.; MacDougall, A.; Burke, E.; Decharme, B.
2016-02-01
We perform a land-surface model intercomparison to investigate how the simulation of permafrost area on the Tibetan Plateau (TP) varies among six modern stand-alone land-surface models (CLM4.5, CoLM, ISBA, JULES, LPJ-GUESS, UVic). We also examine the variability in simulated permafrost area and distribution introduced by five different methods of diagnosing permafrost (from modeled monthly ground temperature, mean annual ground and air temperatures, air and surface frost indexes). There is good agreement (99 to 135 × 104 km2) between the two diagnostic methods based on air temperature which are also consistent with the observation-based estimate of actual permafrost area (101 × 104 km2). However the uncertainty (1 to 128 × 104 km2) using the three methods that require simulation of ground temperature is much greater. Moreover simulated permafrost distribution on the TP is generally only fair to poor for these three methods (diagnosis of permafrost from monthly, and mean annual ground temperature, and surface frost index), while permafrost distribution using air-temperature-based methods is generally good. Model evaluation at field sites highlights specific problems in process simulations likely related to soil texture specification, vegetation types and snow cover. Models are particularly poor at simulating permafrost distribution using the definition that soil temperature remains at or below 0 °C for 24 consecutive months, which requires reliable simulation of both mean annual ground temperatures and seasonal cycle, and hence is relatively demanding. Although models can produce better permafrost maps using mean annual ground temperature and surface frost index, analysis of simulated soil temperature profiles reveals substantial biases. The current generation of land-surface models need to reduce biases in simulated soil temperature profiles before reliable contemporary permafrost maps and predictions of changes in future permafrost distribution can be made for the Tibetan Plateau.
Love stories can be unpredictable: Jules et Jim in the vortex of life.
Dercole, Fabio; Rinaldi, Sergio
2014-06-01
Love stories are dynamic processes that begin, develop, and often stay for a relatively long time in a stationary or fluctuating regime, before possibly fading. Although they are, undoubtedly, the most important dynamic process in our life, they have only recently been cast in the formal frame of dynamical systems theory. In particular, why it is so difficult to predict the evolution of sentimental relationships continues to be largely unexplained. A common reason for this is that love stories reflect the turbulence of the surrounding social environment. But we can also imagine that the interplay of the characters involved contributes to make the story unpredictable-that is, chaotic. In other words, we conjecture that sentimental chaos can have a relevant endogenous origin. To support this intriguing conjecture, we mimic a real and well-documented love story with a mathematical model in which the environment is kept constant, and show that the model is chaotic. The case we analyze is the triangle described in Jules et Jim, an autobiographic novel by Henri-Pierre Roché that became famous worldwide after the success of the homonymous film directed by François Truffaut.
Evaluating soil moisture constraints on surface fluxes in land surface models globally
NASA Astrophysics Data System (ADS)
Harris, Phil; Gallego-Elvira, Belen; Taylor, Christopher; Folwell, Sonja; Ghent, Darren; Veal, Karen; Hagemann, Stefan
2016-04-01
Soil moisture availability exerts a strong control over land evaporation in many regions. However, global climate models (GCMs) disagree on when and where evaporation is limited by soil moisture. Evaluation of the relevant modelled processes has suffered from a lack of reliable, global observations of land evaporation at the GCM grid box scale. Satellite observations of land surface temperature (LST) offer spatially extensive but indirect information about the surface energy partition and, under certain conditions, about soil moisture availability on evaporation. Specifically, as soil moisture decreases during rain-free dry spells, evaporation may become limited leading to increases in LST and sensible heat flux. We use MODIS Terra and Aqua observations of LST at 1 km from 2000 to 2012 to assess changes in the surface energy partition during dry spells lasting 10 days or longer. The clear-sky LST data are aggregated to a global 0.5° grid before being composited as a function dry spell day across many events in a particular region and season. These composites are then used to calculate a Relative Warming Rate (RWR) between the land surface and near-surface air. This RWR can diagnose the typical strength of short term changes in surface heat fluxes and, by extension, changes in soil moisture limitation on evaporation. Offline land surface model (LSM) simulations offer a relatively inexpensive way to evaluate the surface processes of GCMs. They have the benefits that multiple models, and versions of models, can be compared on a common grid and using unbiased forcing. Here, we use the RWR diagnostic to assess global, offline simulations of several LSMs (e.g., JULES and JSBACH) driven by the WATCH Forcing Data-ERA Interim. Both the observed RWR and the LSMs use the same 0.5° grid, which allows the observed clear-sky sampling inherent in the underlying MODIS LST to be applied to the model outputs directly. This approach avoids some of the difficulties in analysing free-running simulations in which land and atmosphere are coupled and, as such, it provides a flexible intermediate step in the assessment of surface processes in GCMs.
EMPIRE and pyenda: Two ensemble-based data assimilation systems written in Fortran and Python
NASA Astrophysics Data System (ADS)
Geppert, Gernot; Browne, Phil; van Leeuwen, Peter Jan; Merker, Claire
2017-04-01
We present and compare the features of two ensemble-based data assimilation frameworks, EMPIRE and pyenda. Both frameworks allow to couple models to the assimilation codes using the Message Passing Interface (MPI), leading to extremely efficient and fast coupling between models and the data-assimilation codes. The Fortran-based system EMPIRE (Employing Message Passing Interface for Researching Ensembles) is optimized for parallel, high-performance computing. It currently includes a suite of data assimilation algorithms including variants of the ensemble Kalman and several the particle filters. EMPIRE is targeted at models of all kinds of complexity and has been coupled to several geoscience models, eg. the Lorenz-63 model, a barotropic vorticity model, the general circulation model HadCM3, the ocean model NEMO, and the land-surface model JULES. The Python-based system pyenda (Python Ensemble Data Assimilation) allows Fortran- and Python-based models to be used for data assimilation. Models can be coupled either using MPI or by using a Python interface. Using Python allows quick prototyping and pyenda is aimed at small to medium scale models. pyenda currently includes variants of the ensemble Kalman filter and has been coupled to the Lorenz-63 model, an advection-based precipitation nowcasting scheme, and the dynamic global vegetation model JSBACH.
NASA Astrophysics Data System (ADS)
Egea, G.; Verhoef, A.; Vidale, P. L.; Black, E.; Van den Hoof, C.
2012-04-01
Coupled photosynthesis-stomatal conductance (A-gs) models are commonly used in ecosystem models to represent the exchange rate of CO2 and H2O between vegetation and the atmosphere. The ways these models account for water stress differ greatly among modelling schemes. This study provides insight into the impact of contrasting model configurations of water stress on the simulated leaf-level values of net photosynthesis (A), stomatal conductance (gs), the functional relationship among them and their ratio, the intrinsic water use efficiency (A/gs), as soil dries. A simple, yet versatile, normalized soil moisture dependent function was used to account for the effects of water stress on gs, on mesophyll conductance (gm ) and on the biochemical capacity (Egea et al., 2011). Model output was compared to leaf-level values obtained from the literature. The sensitivity analyses emphasized the necessity to combine both stomatal and non-stomatal limitations of A in coupled A-gs models to accurately capture the observed functional relationships A vs. gs and A/gs vs. gs in response to drought. Accounting for water stress in coupled A-gs models by imposing either stomatal or biochemical limitations of A, as commonly practiced in most ecosystem models, failed to reproduce the observed functional relationship between key leaf gas exchange attributes. A quantitative limitation analysis revealed that the general pattern of C3 photosynthetic response to water stress can be represented in coupled A-gs models by imposing the highest limitation strength to mesophyll conductance, then to stomatal conductance and finally to the biochemical capacity. This more realistic representation of soil water stress on the simulated leaf-level values of A and gs was embedded in the JULES (Joint UK Land Environment Simulator; Best et al., 2011), model and tested for a number of vegetation types, for which driving and flux verification data were available. These simulations provide an insight into the effect that the revised parameterization will have on GCM simulations of climate variability and change. Best, M. J. et al. (2011). The Joint UK Land Environment Simulator (JULES), model description - Part 1: Energy and water fluxes. Geosci. Model Dev., 4, 677-699. Egea, G., Verhoef, A., Vidale, P.L. (2011) Towards an improved and more flexible representation of water stress in coupled photosynthesis-stomatal conductance models. Agricultural and Forest Meteorology, 151 (10), 1370-1384.
A motor-driven syringe-type gradient maker for forming immobilized pH gradient gels.
Fawcett, J S; Sullivan, J V; Chidakel, B E; Chrambach, A
1988-05-01
A motor driven gradient maker based on the commercial model (Jule Inc., Trumbull, CT) was designed for immobilized pH gradient gels to provide small volumes, rapid stirring and delivery, strict volume and temperature control and air exclusion. The device was constructed and by a convenient procedure yields highly reproducible gradients either in solution or on polyacrylamide gels.
NASA Astrophysics Data System (ADS)
Bhuiyan, M. A. E.; Nikolopoulos, E. I.; Anagnostou, E. N.
2017-12-01
Quantifying the uncertainty of global precipitation datasets is beneficial when using these precipitation products in hydrological applications, because precipitation uncertainty propagation through hydrologic modeling can significantly affect the accuracy of the simulated hydrologic variables. In this research the Iberian Peninsula has been used as the study area with a study period spanning eleven years (2000-2010). This study evaluates the performance of multiple hydrologic models forced with combined global rainfall estimates derived based on a Quantile Regression Forests (QRF) technique. In QRF technique three satellite precipitation products (CMORPH, PERSIANN, and 3B42 (V7)); an atmospheric reanalysis precipitation and air temperature dataset; satellite-derived near-surface daily soil moisture data; and a terrain elevation dataset are being utilized in this study. A high-resolution, ground-based observations driven precipitation dataset (named SAFRAN) available at 5 km/1 h resolution is used as reference. Through the QRF blending framework the stochastic error model produces error-adjusted ensemble precipitation realizations, which are used to force four global hydrological models (JULES (Joint UK Land Environment Simulator), WaterGAP3 (Water-Global Assessment and Prognosis), ORCHIDEE (Organizing Carbon and Hydrology in Dynamic Ecosystems) and SURFEX (Stands for Surface Externalisée) ) to simulate three hydrologic variables (surface runoff, subsurface runoff and evapotranspiration). The models are forced with the reference precipitation to generate reference-based hydrologic simulations. This study presents a comparative analysis of multiple hydrologic model simulations for different hydrologic variables and the impact of the blending algorithm on the simulated hydrologic variables. Results show how precipitation uncertainty propagates through the different hydrologic model structures to manifest in reduction of error in hydrologic variables.
NASA Astrophysics Data System (ADS)
Dumedah, Gift; Walker, Jeffrey P.
2017-03-01
The sources of uncertainty in land surface models are numerous and varied, from inaccuracies in forcing data to uncertainties in model structure and parameterizations. Majority of these uncertainties are strongly tied to the overall makeup of the model, but the input forcing data set is independent with its accuracy usually defined by the monitoring or the observation system. The impact of input forcing data on model estimation accuracy has been collectively acknowledged to be significant, yet its quantification and the level of uncertainty that is acceptable in the context of the land surface model to obtain a competitive estimation remain mostly unknown. A better understanding is needed about how models respond to input forcing data and what changes in these forcing variables can be accommodated without deteriorating optimal estimation of the model. As a result, this study determines the level of forcing data uncertainty that is acceptable in the Joint UK Land Environment Simulator (JULES) to competitively estimate soil moisture in the Yanco area in south eastern Australia. The study employs hydro genomic mapping to examine the temporal evolution of model decision variables from an archive of values obtained from soil moisture data assimilation. The data assimilation (DA) was undertaken using the advanced Evolutionary Data Assimilation. Our findings show that the input forcing data have significant impact on model output, 35% in root mean square error (RMSE) for 5cm depth of soil moisture and 15% in RMSE for 15cm depth of soil moisture. This specific quantification is crucial to illustrate the significance of input forcing data spread. The acceptable uncertainty determined based on dominant pathway has been validated and shown to be reliable for all forcing variables, so as to provide optimal soil moisture. These findings are crucial for DA in order to account for uncertainties that are meaningful from the model standpoint. Moreover, our results point to a proper treatment of input forcing data in general land surface and hydrological model estimation.
NASA Astrophysics Data System (ADS)
Quaife, T. L.; Davenport, I. J.; Lines, E.; Styles, J.; Lewis, P.; Gurney, R. J.
2012-12-01
Satellite observations offer a spatially and temporally synoptic data source for constraining models of land surface processes, but exploitation of these data for such purposes has been largely ad-hoc to date. In part this is because traditional land surface models, and hence most land surface data assimilation schemes, have tended to focus on a specific component of the land surface problem; typically either surface fluxes of water and energy or biogeochemical cycles such as carbon and nitrogen. Furthermore the assimilation of satellite data into such models tends to be restricted to a single wavelength domain, for example passive microwave, thermal or optical, depending on the problem at hand. The next generation of land surface schemes, such as the Joint UK Land Environment Simulator (JULES) and the US Community Land Model (CLM) represent a broader range of processes but at the expense of increasing overall model complexity and in some cases reducing the level of detail in specific processes to accommodate this. Typically, the level of physical detail used to represent the interaction of electromagnetic radiation with the surface is not sufficient to enable prediction of intrinsic satellite observations (reflectance, brightness temperature and so on) and consequently these are not assimilated directly into the models. A seemingly attractive alternative is to assimilate high-level products derived from satellite observations but these are often only superficially related to the corresponding variables in land surface models due to conflicting assumptions between the two. This poster describes the water and energy balance modeling components of a project funded by the European Space Agency to develop a data assimilation scheme for the land surface and observation operators to translate between models and the intrinsic observations acquired by satellite missions. The rationale behind the design of the underlying process model is to represent the physics of the water and energy balance in as parsimonious manner as possible, using a force-restore approach, but describing the physics of electromagnetic radiation scattering at the surface sufficiently well that it is possible to assimilate the intrinsic observations made by remote sensing instruments. In this manner the initial configuration of the resulting scheme will be able to make optimal use of available satellite observations at arbitrary wavelengths and geometries. Model complexity can then be built up from this point whilst ensuring consistency with satellite observations.
NASA Astrophysics Data System (ADS)
Galbraith, D.; Levine, N. M.; Christoffersen, B. O.; Imbuzeiro, H. A.; Powell, T.; Costa, M. H.; Saleska, S. R.; Moorcroft, P. R.; Malhi, Y.
2014-12-01
The mathematical codes embedded within different vegetation models ultimately represent alternative hypotheses of biosphere functioning. While formulations for some processes (e.g. leaf-level photosynthesis) are often shared across vegetation models, other processes (e.g. carbon allocation) are much more variable in their representation across models. This creates the opportunity for equifinality - models can simulate similar values of key metrics such as NPP or biomass through very different underlying causal pathways. Intensive carbon cycle measurements allow for quantification of a comprehensive suite of carbon fluxes such as the productivity and respiration of leaves, roots and wood, allowing for in-depth assessment of carbon flows within ecosystems. Thus, they provide important information on poorly-constrained C-cycle processes such as allocation. We conducted an in-depth evaluation of the ability of four commonly used dynamic global vegetation models (CLM, ED2, IBIS, JULES) to simulate carbon cycle processes at ten lowland Amazonian rainforest sites where individual C-cycle components have been measured. The rigorous model-data comparison procedure allowed identification of biases which were specific to different models, providing clear avenues for model improvement and allowing determination of internal C-cycling pathways that were better supported by data. Furthermore, the intensive C-cycle data allowed for explicit testing of the validity of a number of assumptions made by specific models in the simulation of carbon allocation and plant respiration. For example, the ED2 model assumes that maintenance respiration of stems is negligible while JULES assumes equivalent allocation of NPP to fine roots and leaves. We argue that field studies focusing on simultaneous measurement of a large number of component fluxes are fundamentally important for reducing uncertainty in vegetation model simulations.
NASA Astrophysics Data System (ADS)
Turner, Andrew; Bhat, Gs; Evans, Jonathan; Marsham, John; Martin, Gill; Parker, Douglas; Taylor, Chris; Bhattacharya, Bimal; Madan, Ranju; Mitra, Ashis; Mrudula, Gm; Muddu, Sekhar; Pattnaik, Sandeep; Rajagopal, En; Tripathi, Sachida
2015-04-01
The monsoon supplies the majority of water in South Asia, making understanding and predicting its rainfall vital for the growing population and economy. However, modelling and forecasting the monsoon from days to the season ahead is limited by large model errors that develop quickly, with significant inter-model differences pointing to errors in physical parametrizations such as convection, the boundary layer and land surface. These errors persist into climate projections and many of these errors persist even when increasing resolution. At the same time, a lack of detailed observations is preventing a more thorough understanding of monsoon circulation and its interaction with the land surface: a process governed by the boundary layer and convective cloud dynamics. The INCOMPASS project will support and develop modelling capability in Indo-UK monsoon research, including test development of a new Met Office Unified Model 100m-resolution domain over India. The first UK detachment of the FAAM research aircraft to India, in combination with an intensive ground-based observation campaign, will gather new observations of the surface, boundary layer structure and atmospheric profiles to go with detailed information on the timing of monsoon rainfall. Observations will be focused on transects in the northern plains of India (covering a range of surface types from irrigated to rain-fed agriculture, and wet to dry climatic zones) and across the Western Ghats and rain shadow in southern India (including transitions from land to ocean and across orography). A pilot observational campaign is planned for summer 2015, with the main field campaign to take place during spring/summer 2016. This project will advance our ability to forecast the monsoon, through a programme of measurements and modelling that aims to capture the key surface-atmosphere feedback processes in models. The observational analysis will allow a unique and unprecedented characterization of monsoon processes that will feed directly into model development at the UK Met Office and Indian NCMRWF, through model evaluation at a range of scales and leading to model improvement by working directly with parametrization developers. The project will institute a new long-term series of measurements of land surface fluxes, a particularly unconstrained observation for India, through eddy covariance flux towers. Combined with detailed land surface modelling using the Joint UK Land Environment Simulator (JULES) model, this will allow testing of land surface initialization in monsoon forecasts and improved land-atmosphere coupling.
2016-11-09
Relatively young craters, with sharp crater rims and streaks of bright material, are the focus of this view of Ceres from NASA's Dawn spacecraft. The large, ancient and quite degraded crater Fluusa is seen at top center. The younger craters are Kupalo, at lower right, and Juling, to its left. Dawn took this image on Oct. 17, 2016, from its second extended-mission science orbit (XMO2), at a distance of about 920 miles (1,480 kilometers) above the surface. The image resolution is about 460 feet (140 meters) per pxel. http://photojournal.jpl.nasa.gov/catalog/PIA21223
Volkov prepares for the undocking of the ESA Jules Verne ATV during Expedition 17
2008-09-05
ISS017-E-015230 (5 Sept. 2008) --- Russian Federal Space Agency cosmonaut Sergei Volkov, Expedition 17 commander, makes preparations in the International Space Station's Zvezda Service Module for the undocking of the European Space Agency's (ESA) "Jules Verne" Automated Transfer Vehicle (ATV). The ATV departed from the aft port of Zvezda at 4:29 p.m. (CDT) on Sept. 5, 2008 and was placed in a parking orbit for three weeks, scheduled to be deorbited on Sept. 29 when lighting conditions are correct for an ESA imagery experiment of reentry.
Assessing Ecosystem Model Performance in Semiarid Systems
NASA Astrophysics Data System (ADS)
Thomas, A.; Dietze, M.; Scott, R. L.; Biederman, J. A.
2017-12-01
In ecosystem process modelling, comparing outputs to benchmark datasets observed in the field is an important way to validate models, allowing the modelling community to track model performance over time and compare models at specific sites. Multi-model comparison projects as well as models themselves have largely been focused on temperate forests and similar biomes. Semiarid regions, on the other hand, are underrepresented in land surface and ecosystem modelling efforts, and yet will be disproportionately impacted by disturbances such as climate change due to their sensitivity to changes in the water balance. Benchmarking models at semiarid sites is an important step in assessing and improving models' suitability for predicting the impact of disturbance on semiarid ecosystems. In this study, several ecosystem models were compared at a semiarid grassland in southwestern Arizona using PEcAn, or the Predictive Ecosystem Analyzer, an open-source eco-informatics toolbox ideal for creating the repeatable model workflows necessary for benchmarking. Models included SIPNET, DALEC, JULES, ED2, GDAY, LPJ-GUESS, MAESPA, CLM, CABLE, and FATES. Comparison between model output and benchmarks such as net ecosystem exchange (NEE) tended to produce high root mean square error and low correlation coefficients, reflecting poor simulation of seasonality and the tendency for models to create much higher carbon sources than observed. These results indicate that ecosystem models do not currently adequately represent semiarid ecosystem processes.
Volkov and Kononenko prepare for the undocking of the ESA Jules Verne ATV during Expedition 17
2008-09-05
ISS017-E-015234 (5 Sept. 2008) --- Russian Federal Space Agency cosmonauts Sergei Volkov (left) and Oleg Kononenko, Expedition 17 commander and flight engineer, respectively, make preparations in the International Space Station's Zvezda Service Module for the undocking of the European Space Agency's (ESA) "Jules Verne" Automated Transfer Vehicle (ATV). The ATV departed from the aft port of Zvezda at 4:29 p.m. (CDT) on Sept. 5, 2008 and was placed in a parking orbit for three weeks, scheduled to be deorbited on Sept. 29 when lighting conditions are correct for an ESA imagery experiment of reentry.
Volkov and Kononenko prepare for the undocking of the ESA Jules Verne ATV during Expedition 17
2008-09-05
ISS017-E-015229 (5 Sept. 2008) --- Russian Federal Space Agency cosmonauts Sergei Volkov (left) and Oleg Kononenko, Expedition 17 commander and flight engineer, respectively, make preparations in the International Space Station's Zvezda Service Module for the undocking of the European Space Agency's (ESA) "Jules Verne" Automated Transfer Vehicle (ATV). The ATV departed from the aft port of Zvezda at 4:29 p.m. (CDT) on Sept. 5, 2008 and was placed in a parking orbit for three weeks, scheduled to be deorbited on Sept. 29 when lighting conditions are correct for an ESA imagery experiment of reentry.
Jules Cotard (1840-1889): his life and the unique syndrome which bears his name.
Pearn, J; Gardner-Thorpe, C
2002-05-14
Dr. Jules Cotard (1840-1889) was a Parisian neurologist who first described the délire des négations. Cotard's syndrome or Cotard's delusion comprises any one of a series of delusions ranging from the fixed and unshakable belief that one has lost organs, blood, or body parts to believing that one has lost one's soul or is dead. In its most profound form, the delusion takes the form of a professed belief that one does not exist. Encountered primarily in psychoses such as schizophrenia and bipolar disorder, Cotard's syndrome has also been described in organic lesions of the nondominant temporoparietal cortex as well as in migraine. Cotard's delusion is the only self-certifiable syndrome of delusional psychosis. Jules Cotard, a Parisian neurologist and psychiatrist and former military surgeon, was one of the first to induce cerebral atrophy by the experimental embolization of cerebral arteries in animals and a pioneer in studies of the clinicopathologic correlates of cerebral atrophy secondary to perinatal and postnatal pathologic changes. He was the first to record that unilateral cerebral atrophy in infancy does not necessarily lead to aphasia and was also the pioneer of studies of altered conscious states in diabetic hyperglycemia.
How much rainfall sustained a Green Sahara during the mid-Holocene?
NASA Astrophysics Data System (ADS)
Hopcroft, Peter; Valdes, Paul; Harper, Anna
2016-04-01
The present-day Sahara desert has periodically transformed to an area of lakes and vegetation during the Quaternary in response to orbitally-induced changes in the monsoon circulation. Coupled atmosphere-ocean general circulation model simulations of the mid-Holocene generally underestimate the required monsoon shift, casting doubt on the fidelity of these models. However, the climatic regime that characterised this period remains unclear. To address this, we applied an ensemble of dynamic vegetation model simulations using two different models: JULES (Joint UK Land Environment Simulator) a comprehensive land surface model, and LPJ (Lund-Potsdam-Jena model) a widely used dynamic vegetation model. The simulations are forced with a number of idealized climate scenarios, in which an observational climatology is progressively altered with imposed anomalies of precipitation and other related variables, including cloud cover and humidity. The applied anomalies are based on an ensemble of general circulation model simulations, and include seasonal variations but are spatially uniform across the region. When perturbing precipitation alone, a significant increase of at least 700mm/year is required to produce model simulations with non-negligible vegetation coverage in the Sahara region. Changes in related variables including cloud cover, surface radiation fluxes and humidity are found to be important in the models, as they modify the water balance and so affect plant growth. Including anomalies in all of these variables together reduces the precipitation change required for a Green Sahara compared to the case of increasing precipitation alone. We assess whether the precipitation changes implied by these vegetation model simulations are consistent with reconstructions for the mid-Holocene from pollen samples. Further, Earth System models predict precipitation increases that are significantly smaller than that inferred from these vegetation model simulations. Understanding this difference presents an ongoing challenge.
Methane mitigation shows significant benefits towards achieving the 1.5 degree target.
NASA Astrophysics Data System (ADS)
Collins, W.; Webber, C.; Cox, P. M.; Huntingford, C.; Lowe, J. A.; Sitch, S.
2017-12-01
Most analyses of allowable carbon emissions to achieve the 1.5 degree target implicitly assume that the ratio of CO2 to non-CO2 greenhouse gases remains near constant, and that all radiative forcing factors have similar impacts on land and ocean carbon storage. Here we determine how plausible reductions in methane emissions will make the carbon targets more feasible. We account for the latest estimates of the methane radiative effect as well as the indirect effects of methane on ozone. We particularly address the differing effects of methane and CO2 mitigation on the land carbon storage including via reduced concentrations of surface ozone. The methodology uses an intermediate complexity climate model (IMOGEN) coupled to a land surface model (JULES) which represents the details of the terrestrial carbon cycle. The carbon emissions inputs to IMOGEN are varied to find allowable pathways consistent with the Paris 1.5 K or 2.0 K targets. The IMOGEN physical parameters are altered to represent the climate characteristics of 38 CMIP5 models (such as climate sensitivity) to provide bounds on the range of allowable CO2 emissions. We examine the effects of three different methane mitigation options that are broadly consistent with the ranges in the SSP scenarios: little mitigation, cost-optimal mitigation, and maximal mitigation. The land and ocean carbon storage increases with methane mitigation, allowing more flexibility in CO2 emission reduction. This is mostly since CO2 fertilisation is reduced less with high methane mitigation, with a small contribution from reduced plant damage with lower surface ozone levels.
The UKC2 regional coupled prediction system
NASA Astrophysics Data System (ADS)
Castillo, Juan; Lewis, Huw; Graham, Jennifer; Saulter, Andrew; Arnold, Alex; Fallmann, Joachim; Martinez de la Torre, Alberto; Blyth, Eleanor; Bricheno, Lucy
2017-04-01
It is hypothesized that more accurate prediction and warning of natural hazards, such as of the impacts of severe weather through the environment, requires a more integrated approach to forecasting. This approach also delivers research benefits through providing tools with which to explore the known interactions and feedbacks between different physical and biogeochemical components of the environment across sky, sea and land. This hypothesis is being tested in a UK regional context at km-scale through the UK Environmental Prediction Project. This presentation will provide an introduction to the UKC2 UK Environmental Prediction research system. This incorporates models of the atmosphere (Met Office Unified Model), land surface (JULES), shelf-sea ocean (NEMO) and ocean waves (WAVEWATCH III). These components are coupled (via OASIS3-MCT libraries) at unprecedentedly high resolution across the UK and the wider north-west European regional domain. A research framework has been established to explore the representation of feedback processes in coupled and uncoupled modes, providing a unique new research tool for UK environmental science. The presentation will highlight work undertaken to review and improve the computational cost of running these systems for efficient research application. Research will be presented highlighting case study evaluation on the sensitivity of the ocean and surface waves to the representation of feedbacks to the atmosphere, and on the sensitivity of weather systems and boundary layer cloud development to the exchange of heat and momentum at the ocean surface modified through sea surface temperature and wave-induced roughness. The presentation will discuss plans for future development through UKC3 and beyond.
A mechanistic, globally-applicable model of plant nitrogen uptake, retranslocation and fixation
NASA Astrophysics Data System (ADS)
Fisher, J. B.; Tan, S.; Malhi, Y.; Fisher, R. A.; Sitch, S.; Huntingford, C.
2008-12-01
Nitrogen is one of the nutrients that can most limit plant growth, and nitrogen availability may be a controlling factor on biosphere responses to climate change. We developed a plant nitrogen assimilation model based on a) advective transport through the transpiration stream, b) retranslocation whereby carbon is expended to resorb nitrogen from leaves, c) active uptake whereby carbon is expended to acquire soil nitrogen, and d) biological nitrogen fixation whereby carbon is expended for symbiotic nitrogen fixers. The model relies on 9 inputs: 1) net primary productivity (NPP), 2) plant C:N ratio, 3) available soil nitrogen, 4) root biomass, 5) transpiration rate, 6) saturated soil depth,7) leaf nitrogen before senescence, 8) soil temperature, and 9) ability to fix nitrogen. A carbon cost of retranslocation is estimated based on leaf nitrogen and compared to an active uptake carbon cost based on root biomass and available soil nitrogen; for nitrogen fixers both costs are compared to a carbon cost of fixation dependent on soil temperature. The NPP is then allocated to optimize growth while maintaining the C:N ratio. The model outputs are total plant nitrogen uptake, remaining NPP available for growth, carbon respired to the soil and updated available soil nitrogen content. We test and validate the model (called FUN: Fixation and Uptake of Nitrogen) against data from the UK, Germany and Peru, and run the model under simplified scenarios of primary succession and climate change. FUN is suitable for incorporation into a land surface scheme of a General Circulation Model and will be coupled with a soil model and dynamic global vegetation model as part of a land surface model (JULES).
Orbital Debris Quarterly News. Volume 13; No. 1
NASA Technical Reports Server (NTRS)
Liou, J.-C. (Editor); Shoots, Debi (Editor)
2009-01-01
Topics discussed include: new debris from a decommissioned satellite with a nuclear power source; debris from the destruction of the Fengyun-1C meteorological satellite; quantitative analysis of the European Space Agency's Automated Transfer Vehicle 'Jules Verne' reentry event; microsatellite impact tests; solar cycle 24 predictions and other long-term projections and geosynchronus (GEO) environment for the Orbital Debris Engineering Model (ORDEM2008). Abstracts from the NASA Orbital Debris Program Office, examining satellite reentry risk assessments and statistical issues for uncontrolled reentry hazards, are also included.
NASA Astrophysics Data System (ADS)
García González, Raquel; Verhoef, Anne; Vidale, Pier Luigi; Gan, Guohui; Wu, Yupeng; Hughes, Andrew; Mansour, Majdi; Blyth, Eleanor; Finch, Jon; Main, Bruce
2010-05-01
An increased uptake of alternative low or non-CO2 emitting energy sources is one of the key priorities for policy makers to mitigate the effects of environmental change. Relatively little work has been undertaken on the mitigation potential of Ground Coupled Heat Pumps (GCHPs) despite the fact that a GCHP could significantly reduce CO2 emissions from heating systems. It is predicted that under climate change the most probable scenario is for UK temperatures to increase and for winter rainfall to become more abundant; the latter is likely to cause a general rise in groundwater levels. Summer rainfall may reduce considerably, while vegetation type and density may change. Furthermore, recent studies underline the likelihood of an increase in the number of heat waves. Under such a scenario, GCHPs will increasingly be used for cooling as well as heating. These factors will affect long-term performance of horizontal GCHP systems and hence their economic viability and mitigation potential during their life span ( 50 years). The seasonal temperature differences encountered in soil are harnessed by GCHPs to provide heating in the winter and cooling in the summer. The performance of a GCHP system will depend on technical factors (heat exchanger (HE) type, length, depth, and spacing of pipes), but also it will be determined to a large extent by interactions between the below-ground parts of the system and the environment (atmospheric conditions, vegetation and soil characteristics). Depending on the balance between extraction and rejection of heat from and to the ground, the soil temperature in the neighbourhood of the HE may fall or rise. The GROMIT project (GROund coupled heat pumps MITigation potential), funded by the Natural Environment Research Council (UK), is a multi-disciplinary research project, in collaboration with EarthEnergy Ltd., which aims to quantify the CO2 mitigation potential of horizontal GCHPs. It considers changing environmental conditions and combines model predictions of soil moisture content and soil temperature with measurements at different GCHP locations over the UK. The combined effect of environment dynamics and horizontal GCHP technical properties on long-term GCHP performance will be assessed using a detailed land surface model (JULES: Joint UK Land Environment Simulator, Meteorological Office, UK) with additional equations embedded describing the interaction between GCHP heat exchangers and the surrounding soil. However, a number of key soil physical processes are currently not incorporated in JULES, such as groundwater flow, which, especially in lowland areas, can have an important effect on the heat flow between soil and HE. Furthermore, the interaction between HE and soil may also cause soil vapour and moisture fluxes. These will affect soil thermal conductivity and hence heat flow between the HE and the surrounding soil, which will in turn influence system performance. The project will address these issues. We propose to drive an improved version of JULES (with equations to simulate GCHP exchange embedded), with long-term gridded (1 km) atmospheric, soil and vegetation data (reflecting current and future environmental conditions) to reliably assess the mitigation potential of GCHPs over the entire domain of the UK, where uptake of GCHPs has been low traditionally. In this way we can identify areas that are most suitable for the installation of GCHPs. Only then recommendations can be made to local and regional governments, for example, on how to improve the mitigation potential in less suitable areas by adjusting GCHP configurations or design.
Estimating the CO2 mitigation potential of horizontal Ground Source Heat Pumps in the UK
NASA Astrophysics Data System (ADS)
Garcia-Gonzalez, R.; Verhoef, A.; Vidale, P. L.; Gan, G.; Chong, A.; Clark, D.
2012-04-01
By 2020, the UK will need to generate 15% of its energy from renewables to meet our contribution to the EU renewable energy target. Heating and cooling systems of buildings account for 30%-50% of the global energy consumption; thus, alternative low-carbon technologies such as horizontal Ground Couple Heat Pumps (GCHPs) can contribute to the reduction of anthropogenic CO2 emissions. Horizontal GCHPs currently represent a small fraction of the total energy generation in the UK. However, the fact that semi-detached and detached dwellings represent approximately 40% of the total housing stocks in the UK could make the widespread implementation of this technology particularly attractive in the UK and so could significantly increase its renewable energy generation potential. Using a simulation model, we analysed the dynamic interactions between the environment, the horizontal GCHP heat exchanger and typical UK dwellings, as well as their combined effect on heat pump performance and CO2 mitigation potential. For this purpose, a land surface model (JULES, Joint UK Land Environment Simulator), which calculates coupled soil heat and water fluxes, was combined with a heat extraction model. The analyses took into account the spatio-temporal variability of soil properties (thermal and hydraulic) and meteorological variables, as well as different horizontal GCHP configurations and a variety of building loads and heat demands. Sensitivity tests were performed for four sites in the UK with different climate and soil properties. Our results show that an installation depth of 1.0m would give us higher heat extractions rates, however it would be preferable to install the pipes slightly deeper to avoid the seasonal influence of variable meteorological conditions. A value of 1.5m for the spacing between coils (S) for a slinky configuration type is recommended to avoid thermal disturbances between neighbouring coils. We also found that for larger values of the spacing between the coils (S > 2), a slinky coil diameter (D) of 0.8m might be a better choice in terms of heat extraction rate. The fluid temperature of the pipe had a direct effect on the heat extraction rates of the system. The coefficient of performance of a heat pump did not remain constant and depended on the operating conditions and outdoor temperatures. The outcomes of this study will allow us to give recommendations to installers and relevant government bodies concerning the optimal configuration of future installations of horizontal GCHPs at UK developments. Finally, long-term simulations with the coupled JULES-GCHP model, using high resolution (1 km) meteorological (historical and projected data), soil physical and land cover data over the entire UK-domain, will allow us to explore the effect that global warming will have on future surface and soil temperatures, as well as soil moisture contents, and therefore its impact on the energy demand of the buildings and the CO2 mitigation potential of this type of renewable energy.
Amazon Deforestation Fires Increase Plant Productivity through Changes in Diffuse Radiation
NASA Astrophysics Data System (ADS)
Rap, A.; Reddington, C.; Spracklen, D. V.; Mercado, L.; Haywood, J. M.; Bonal, D.; Butt, N.; Phillips, O.
2013-12-01
Over the past few decades a large increase in carbon storage has been observed in undisturbed forests across Amazonia. The reason for such a sink is unclear, although many possible mechanisms have been suggested, including changes in temperature, carbon dioxide, precipitation, clouds, and solar radiation. In this work we focus on one such mechanism, namely the increase in plant photosynthesis due to changes in diffuse radiation caused by atmospheric aerosols from large-scale deforestation fires that now occur throughout the Amazon region. We estimate that this mechanism has increased dry season (August-September) net primary productivity (NPP) by up to 30% across wide regions of the Amazon. We conclude that aerosol from deforestation fires may be responsible for a substantial fraction of the Amazon carbon sink that has been observed. Our approach is based on the combined use of three models: (i) the Global Model of Aerosol Processes (GLOMAP), (ii) the Edwards-Slingo radiation model, and (iii) the UK Met Office JULES land-surface scheme, constrained against in-situ aerosol and radiation observation datasets from several Amazonian sites. A 10 year (1999-2008) GLOMAP simulation using GFED3 biomass burning emissions is first evaluated against aerosol observations, indicating that the model is able to capture the Amazon aerosol seasonality, with enhanced concentrations during the dry season driven by biomass burning. The radiation scheme is then shown to be in good agreement with total and diffuse radiation in-situ observations, the model being able to capture the high total and low diffuse radiation flux in the dry season, as well as the low total and high diffuse radiation flux in the wet season. We then use our modelling framework to quantify the contribution of deforestation fires to diffuse/direct radiation fraction and forest productivity. We calculate that deforestation fires increase dry season diffuse radiation by up to 60% or 30 Wm-2. Finally, we use the JULES model to show that this increase in diffuse radiation is responsible for a substantial growth in gross primary productivity (GPP), enhancing Amazon-wide dry-season GPP by 5% with local increases of up to 15%. Most of this GPP response results in an increase in NPP, estimated in the dry season at 10% across the Amazon with local increases as large as 30%. This substantial NPP enhancement spatially matches observed increases in forest biomass storage across the Amazon. We thus suggest that deforestation fires have an important impact on the Amazon carbon budget and attempt to estimate the fraction of the observed forest carbon sink that can be attributed to this mechanism. Change [%] in diffuse radiation due to deforestation
2004-04-15
Jules Verne published his first science fiction novel in 1865 called "From the Earth to the Moon." As shown here in an illustration, passengers in Verne's space ship enjoy their first taste of weightlessness.
NASA Astrophysics Data System (ADS)
Turner, A. G.; Bhat, G. S.; Evans, J. G.; Madan, R.; Marsham, J. H.; Martin, G.; Mitra, A. K.; Mrudula, G.; Parker, D. J.; Pattnaik, S.; Rajagopal, E. N.; Taylor, C.; Tripathi, S. N.
2016-12-01
INCOMPASS will build on a field and aircraft measurement campaign from the 2016 monsoon onset to better understand and predict monsoon rainfall. The monsoon supplies the majority of water in South Asia, however modelling and forecasting the monsoon from days to the season ahead is limited by large model errors that develop quickly. Likely problems lie in physical parametrizations such as convection, the boundary layer and land surface. At the same time, lack of detailed observations prevents more thorough understanding of monsoon circulation and its interaction with the land surface; a process governed by boundary layer and convective cloud dynamics. From May to July 2016, INCOMPASS used a modified BAe-146 jet aircraft operated by the UK Facility for Airborne Atmospheric Measurements (FAAM), for the first project of this scale in India. The India and UK team flew around 100 hours of science sorties from bases in northern and southern India. Flights from Lucknow in the northern plains took measurements to the west and southeast to allow sampling of the complete contrast from dry desert air to the humid environment over the north Bay of Bengal. These routes were repeated in the pre-monsoon and monsoon phases, measuring contrasting surface and boundary layer structures. In addition, flights from the southern base in Bengaluru measured contrasts from the Arabian Sea, across the intense rains of the Western Ghats mountains, over the rain shadow in southeast India and over the southern Bay of Bengal. Flight planning was performed with the aid of forecasts from a new UK Met Office 4km limited area model. INCOMPASS also installed a network of surface flux towers, as well as operating a cloud-base ceilometer and performing intensive radiosonde launches from a supersite in Kanpur. This presentation will outline preliminary results from the field campaign including new observations of the surface, boundary layer structure and atmospheric profiles together with detailed information on the timing of monsoon rain. We also outline our future plans for nested modelling of specific case studies of the 2016 monsoon, at resolutions at of 4km, 2km and 1km with explicit convection, as well as test development of a new 100m model over India. Observations will also be combined with further work using the Joint UK Land Environment Simulator (JULES) model.
1979-08-02
Jules Bergman, ABC Science Newscaster stands by a NASA Ames press room for the continuing information being returned by the Pioneer spacecraft during it's encounter with the planet Saturn and it's rings.
2016-03-29
This view from NASA Dawn spacecraft shows an area in mid-southern latitudes on Ceres. The crater named Juling 12 miles, 20 kilometers wide is seen at lower right. Bright material is visible along its upper walls.
In Jules Verne's Footsteps: Seismology in the source
NASA Astrophysics Data System (ADS)
Ellsworth, Bill; Ito, Hisao; Malin, Peter; Abercrombie, Rachel
When Professor Otto Lidenbrock led his little band to the center of the Earth in Jules Verne's 1864 classic novel, the intrepid adventurers needed little more than practical 19th century clothes to provide them with comfort and protection. How different the science of earthquakes would be if conditions in the Earth were really so friendly to the would-be observer. Even the operation of seismic sensors at the relatively modest depth of 2-3 km, roughly the depth of the shallowest crustal earthquakes, requires careful precautions against the effects of unstable materials, temperature, pressure, and water for successful long-term observations to be made. Indeed, the handful of successful deep borehole experiments that have been conducted to date have depended on simple sensors with limited bandwidth and dynamic range, and have yielded data that were not ideally suited to investigating the details of the earthquake source.
Humidity influence on atomic force microscopy electrostatic nanolithography
NASA Astrophysics Data System (ADS)
Lyuksyutov, Sergei; Juhl, Shane; Vaia, Richard
2006-03-01
The formation and sustainability of water menisci and bridges between solid dielectric surface and nano-asperity under external electrostatic potential is a mystery, which must be adequately explained. The goal of our study is twofold: (i) To address the influence of an ambient humidity through the water meniscus formation on the nanostructure formation in soften polymeric surfaces; (ii) Estimate an electric charge generation and transport inside the water meniscus in vicinity of nanoscale asperity taking into consideration an induced water ionization in strong non-uniform electric field of magnitude up to 10^10 Vm-1. It is suspected that strong electric field inside a polymer matrix activates the hoping mechanism of conductivity. The electrons are supplied by tunneling of conductive tip, and also through water ionization. Electric current associated with these free carriers produces Jule heating of a small volume of polymer film heating it above the glass transition temperature. Nanostructures are created by mass transport of visco-elastic polymer melt enabling high structure densities on polymer film.
NASA Astrophysics Data System (ADS)
Reinsch, S.; Emmett, B.; Cosby, J.; Mercado, L. M.; Smart, S.; Glanville, H.; Alberola, M. B.; Clark, D.; Robinson, E.; Jones, D.
2015-12-01
The coupling of C, N and P cycles has rarely been studied through the air- land-water continuum. This is essential if we are to enhance land-atmosphere models to account for N and P limitations. It is also important for developing integrated catchment management solutions to deliver improved water quality combined with a wide range of other ecosystem functions and services.We present results from a project which is part of the interdisciplinary pan-UK NERC Macronutrient Cycles Programme (macronutrient-cycles.ouce.ox.ac.uk/). Our aim is to quantify how coupled C, N & P cycles change across a land use intensification gradient from arable to grass, woodland and bog ecosystems and identify the implications for land-atmosphere C exchange. We focus on three key processes; photosynthesis, annual net primary productivity (ANPP) and decomposition and explore their consequences for biodiversity. Other aspects of the project track delivery to, and transformations within, the freshwater and coastal systems. When we explore relationships between C, N and P, results indicate all habitat types fall on a single land use intensification gradient. Stoichiometry suggests plant productivity is primarily N limited. P limitation occurs rarely but at all levels of intensification. Soil priming shows our soils are primarily C limited and, surprisingly, soil acidity provides one of the most powerful single predictors of processes and ecosystem services perhaps as it is a good integrator of many soil properties. Incorporating this knowledge into the UK land-atmosphere model JULES will be used to improve ANPP projections. These will then be used as inputs into a plant species model called MULTIMOVE to enable future scenarios of climate change, land use and air pollution on habitat suitability for > 1400 plant species to be explored. The enhanced Jules model will ensure both N and P limitations on C fluxes from above and below-ground are incorporated into future UK scenario applications.
NASA Astrophysics Data System (ADS)
Reinsch, Sabine; Glanville, Helen; Smart, Simon; Jones, Davey; Mercado, Lina; Blanes-Alberola, Mamen; Cosby, Jack; Emmett, Bridget
2016-04-01
The coupling of C, N and P cycles has rarely been studied through the air- land-water continuum. This is essential if we are to enhance land-atmosphere models to account for N and P limitations. It is also important for developing integrated catchment management solutions to deliver improved water quality combined with a wide range of other ecosystem functions and services. We present results from a project which is part of the interdisciplinary pan-UK NERC Macronutrient Cycles Programme (macronutrient-cycles.ouce.ox.ac.uk/). Our aim is to quantify how coupled C, N & P cycles change across a land use intensification gradient from arable to grass, woodland and bog ecosystems and identify the implications for land-atmosphere C exchange. We focus on three key processes; photosynthesis, annual net primary productivity and decomposition and explore their consequences for biodiversity. Other aspects of the project track delivery to, and transformations within, the freshwater and coastal systems. When we explore relationships between C, N and P, results indicate all habitat types fall on a single land use intensification gradient. Stoichiometry suggests plant productivity is primarily N limited. P limitation occurs rarely but at all levels of intensification. Soil priming shows our soils are primarily C limited and, surprisingly, soil acidity provides one of the most powerful single predictors of processes and ecosystem services perhaps as it is a good integrator of many soil properties. Incorporating this knowledge into the UK land-atmosphere model JULES will improve aNPP projections. These are then being used as inputs into a plant species model called MULTIMOVE to enable future scenarios of climate change, land use and air pollution on habitat suitability for > 1400 plant species to be explored. The enhanced Jules model will ensure both N and P limitations on C fluxes from above and below-ground are incorporated into future UK scenario applications.
Integrating 3D geological information with a national physically-based hydrological modelling system
NASA Astrophysics Data System (ADS)
Lewis, Elizabeth; Parkin, Geoff; Kessler, Holger; Whiteman, Mark
2016-04-01
Robust numerical models are an essential tool for informing flood and water management and policy around the world. Physically-based hydrological models have traditionally not been used for such applications due to prohibitively large data, time and computational resource requirements. Given recent advances in computing power and data availability, a robust, physically-based hydrological modelling system for Great Britain using the SHETRAN model and national datasets has been created. Such a model has several advantages over less complex systems. Firstly, compared with conceptual models, a national physically-based model is more readily applicable to ungauged catchments, in which hydrological predictions are also required. Secondly, the results of a physically-based system may be more robust under changing conditions such as climate and land cover, as physical processes and relationships are explicitly accounted for. Finally, a fully integrated surface and subsurface model such as SHETRAN offers a wider range of applications compared with simpler schemes, such as assessments of groundwater resources, sediment and nutrient transport and flooding from multiple sources. As such, SHETRAN provides a robust means of simulating numerous terrestrial system processes which will add physical realism when coupled to the JULES land surface model. 306 catchments spanning Great Britain have been modelled using this system. The standard configuration of this system performs satisfactorily (NSE > 0.5) for 72% of catchments and well (NSE > 0.7) for 48%. Many of the remaining 28% of catchments that performed relatively poorly (NSE < 0.5) are located in the chalk in the south east of England. As such, the British Geological Survey 3D geology model for Great Britain (GB3D) has been incorporated, for the first time in any hydrological model, to pave the way for improvements to be made to simulations of catchments with important groundwater regimes. This coupling has involved development of software to allow for easy incorporation of geological information into SHETRAN for any model setup. The addition of more realistic subsurface representation following this approach is shown to greatly improve model performance in areas dominated by groundwater processes. The resulting modelling system has great potential to be used as a resource at national, regional and local scales in an array of different applications, including climate change impact assessments, land cover change studies and integrated assessments of groundwater and surface water resources.
Exposure / Ritual Prevention Therapy Boosts Antidepressant Treatment of OCD
... 24026506 Grants: MH045436 , MH45404 . Clinical Trial: 00389493 Share Contact(s) Jules Asher NIMH Press Office 301-443-4536 ... More Science News about Obsessive-Compulsive Disorder (OCD) Contact the Press Office 301-443-4536 NIMHpress@nih. ...
21. INTERIOR, DETAIL VIEW OF PARLOR, FIRST FLOOR, SOUTH ROOM, ...
21. INTERIOR, DETAIL VIEW OF PARLOR, FIRST FLOOR, SOUTH ROOM, NORTHWEST CORNER SHOWING PANELED WALLS AND PAINTING OVER DOORWAY (PAINTED BY FORMER RESIDENT, JULES DIEUDONNE) - Bostwick Hall, 3901 Forty-eighth Street, Bladensburg, Prince George's County, MD
Fraser, Tricia; Brown, Paul D.
2017-01-01
Leptospirosis is a zooanthroponosis aetiologically caused by pathogenic bacteria belonging to the genus, Leptospira. Environmental signals such as increases in temperatures or oxidative stress can trigger response regulatory modes of virulence genes during infection. This study sought to determine the effect of temperature and oxidative stress on virulence associated genes in highly passaged Leptospira borgpeterseneii Jules and L. interrogans Portlandvere. Bacteria were grown in EMJH at 30°C, 37°C, or at 30°C before being transferred to 37°C. A total of 14 virulence-associated genes (fliY, invA, lenA, ligB, lipL32, lipL36, lipL41, lipL45, loa22, lsa21, mce, ompL1, sph2, and tlyC) were assessed using endpoint PCR. Transcriptional analyses of lenA, lipL32, lipL41, loa22, sph2 were assessed by quantitative real-time RT-PCR at the temperature conditions. To assess oxidative stress, bacteria were exposed to H2O2 for 30 and 60 min with or without the temperature stress. All genes except ligB (for Portlandvere) and ligB and mce (for Jules) were detectable in the strains. Quantitatively, temperature stress resulted in significant changes in gene expression within species or between species. Temperature changes were more influential in gene expression for Jules, particularly at 30°C and upshift conditions; at 37°C, expression levels were higher for Portlandvere. However, compared to Jules, where temperature was influential in two of five genes, temperature was an essential element in four of five genes in Portlandvere exposed to oxidative stress. At both low and high oxidative stress levels, the interplay between genetic predisposition (larger genome size) and temperature was biased towards Portlandvere particularly at 30°C and upshift conditions. While it is clear that expression of many virulence genes in highly passaged strains of Leptospira are attenuated or lost, genetic predisposition, changes in growth temperature and/or oxidative intensity and/or duration were factors which acted in isolation or together with other regulatory cues to contribute to the variable gene expression observed in this study. Overall, differential gene expression in serovar Portlandvere was more responsive to temperature and oxidative stress. PMID:28536558
Revisiting the PLUMBER Experiments from a Process-Diagnostics Perspective
NASA Astrophysics Data System (ADS)
Nearing, G. S.; Ruddell, B. L.; Clark, M. P.; Nijssen, B.; Peters-Lidard, C. D.
2017-12-01
The PLUMBER benchmarking experiments [1] showed that some of the most sophisticated land models (CABLE, CH-TESSEL, COLA-SSiB, ISBA-SURFEX, JULES, Mosaic, Noah, ORCHIDEE) were outperformed - in simulations of half-hourly surface energy fluxes - by instantaneous, out-of-sample, and globally-stationary regressions with no state memory. One criticism of PLUMBER is that the benchmarking methodology was not derived formally, so that applying a similar methodology with different performance metrics can result in qualitatively different results. Another common criticism of model intercomparison projects in general is that they offer little insight into process-level deficiencies in the models, and therefore are of marginal value for helping to improve the models. We address both of these issues by proposing a formal benchmarking methodology that also yields a formal and quantitative method for process-level diagnostics. We apply this to the PLUMBER experiments to show that (1) the PLUMBER conclusions were generally correct - the models use only a fraction of the information available to them from met forcing data (<50% by our analysis), and (2) all of the land models investigated by PLUMBER have similar process-level error structures, and therefore together do not represent a meaningful sample of structural or epistemic uncertainty. We conclude by suggesting two ways to improve the experimental design of model intercomparison and/or model benchmarking studies like PLUMBER. First, PLUMBER did not report model parameter values, and it is necessary to know these values to separate parameter uncertainty from structural uncertainty. This is a first order requirement if we want to use intercomparison studies to provide feedback to model development. Second, technical documentation of land models is inadequate. Future model intercomparison projects should begin with a collaborative effort by model developers to document specific differences between model structures. This could be done in a reproducible way using a unified, process-flexible system like SUMMA [2]. [1] Best, M.J. et al. (2015) 'The plumbing of land surface models: benchmarking model performance', J. Hydrometeor. [2] Clark, M.P. et al. (2015) 'A unified approach for process-based hydrologic modeling: 1. Modeling concept', Water Resour. Res.
The UKC2 regional coupled environmental prediction system
NASA Astrophysics Data System (ADS)
Lewis, Huw W.; Castillo Sanchez, Juan Manuel; Graham, Jennifer; Saulter, Andrew; Bornemann, Jorge; Arnold, Alex; Fallmann, Joachim; Harris, Chris; Pearson, David; Ramsdale, Steven; Martínez-de la Torre, Alberto; Bricheno, Lucy; Blyth, Eleanor; Bell, Victoria A.; Davies, Helen; Marthews, Toby R.; O'Neill, Clare; Rumbold, Heather; O'Dea, Enda; Brereton, Ashley; Guihou, Karen; Hines, Adrian; Butenschon, Momme; Dadson, Simon J.; Palmer, Tamzin; Holt, Jason; Reynard, Nick; Best, Martin; Edwards, John; Siddorn, John
2018-01-01
It is hypothesized that more accurate prediction and warning of natural hazards, such as of the impacts of severe weather mediated through various components of the environment, require a more integrated Earth System approach to forecasting. This hypothesis can be explored using regional coupled prediction systems, in which the known interactions and feedbacks between different physical and biogeochemical components of the environment across sky, sea and land can be simulated. Such systems are becoming increasingly common research tools. This paper describes the development of the UKC2 regional coupled research system, which has been delivered under the UK Environmental Prediction Prototype project. This provides the first implementation of an atmosphere-land-ocean-wave modelling system focussed on the United Kingdom and surrounding seas at km-scale resolution. The UKC2 coupled system incorporates models of the atmosphere (Met Office Unified Model), land surface with river routing (JULES), shelf-sea ocean (NEMO) and ocean waves (WAVEWATCH III). These components are coupled, via OASIS3-MCT libraries, at unprecedentedly high resolution across the UK within a north-western European regional domain. A research framework has been established to explore the representation of feedback processes in coupled and uncoupled modes, providing a new research tool for UK environmental science. This paper documents the technical design and implementation of UKC2, along with the associated evaluation framework. An analysis of new results comparing the output of the coupled UKC2 system with relevant forced control simulations for six contrasting case studies of 5-day duration is presented. Results demonstrate that performance can be achieved with the UKC2 system that is at least comparable to its component control simulations. For some cases, improvements in air temperature, sea surface temperature, wind speed, significant wave height and mean wave period highlight the potential benefits of coupling between environmental model components. Results also illustrate that the coupling itself is not sufficient to address all known model issues. Priorities for future development of the UK Environmental Prediction framework and component systems are discussed.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-10
... Receiving Allocation Adrian Jules LTD--Rochester, NY, HMX, LLC-- New York, NY, Hugo Boss Cleveland, Inc... York, NY, HMX, LLC--New York, NY, Hugo Boss Cleveland, Inc.--Brooklyn, OH, JA Apparel Corp.--New York...
[The amazing career of a homeopath, philanthropist, Fourierist, Benoît-Jules Mure. (1809-1858)].
Ségal, Alain; Trépardoux, Francis
2005-01-01
The authors evoke the difficulty of dealing with the life and work of Benoît-Jules Mure who was a homeopathic scientist and a keen specialist on propaganda. He was also an adept of Charles Fourier and he used almost his fortune to the spreading of homeopathy and at time, the improvement of social life. Thus he tried to settle humanitarian colonies in Brazil and later in Egypt, Nubian and Sudan in order to improve their fashion of life. He was hit by tuberculosis which led him discover homeopathy and by his strength of character lie led the idea of his mission in favour of his convictions. He was very angry with the official medical organisation and at last he never has been recognized as a médical doctor. The authors underline that his life and his work have probably left some definite marks in the South America let alone the birth of Socialism.
Radiation Transport Calculation of the UGXR Collimators for the Jules Horowitz Reactor (JHR)
NASA Astrophysics Data System (ADS)
Chento, Yelko; Hueso, César; Zamora, Imanol; Fabbri, Marco; Fuente, Cristina De La; Larringan, Asier
2017-09-01
Jules Horowitz Reactor (JHR), a major infrastructure of European interest in the fission domain, will be built and operated in the framework of an international cooperation, including the development and qualification of materials and nuclear fuel used in nuclear industry. For this purpose UGXR Collimators, two multi slit gamma and X-ray collimation mechatronic systems, will be installed at the JHR pool and at the Irradiated Components Storage pool. Expected amounts of radiation produced by the spent fuel and X-ray accelerator implies diverse aspects need to be verified to ensure adequate radiological zoning and personnel radiation protection. A computational methodology was devised to validate the Collimators design by means of coupling different engineering codes. In summary, several assessments were performed by means of MCNP5v1.60 to fulfil all the radiological requirements in Nominal scenario (TEDE < 25µSv/h) and in Maintenance scenario (TEDE < 2mSv/h) among others, detailing the methodology, hypotheses and assumptions employed.
Benchmarking sensitivity of biophysical processes to leaf area changes in land surface models
NASA Astrophysics Data System (ADS)
Forzieri, Giovanni; Duveiller, Gregory; Georgievski, Goran; Li, Wei; Robestson, Eddy; Kautz, Markus; Lawrence, Peter; Ciais, Philippe; Pongratz, Julia; Sitch, Stephen; Wiltshire, Andy; Arneth, Almut; Cescatti, Alessandro
2017-04-01
Land surface models (LSM) are widely applied as supporting tools for policy-relevant assessment of climate change and its impact on terrestrial ecosystems, yet knowledge of their performance skills in representing the sensitivity of biophysical processes to changes in vegetation density is still limited. This is particularly relevant in light of the substantial impacts on regional climate associated with the changes in leaf area index (LAI) following the observed global greening. Benchmarking LSMs on the sensitivity of the simulated processes to vegetation density is essential to reduce their uncertainty and improve the representation of these effects. Here we present a novel benchmark system to assess model capacity in reproducing land surface-atmosphere energy exchanges modulated by vegetation density. Through a collaborative effort of different modeling groups, a consistent set of land surface energy fluxes and LAI dynamics has been generated from multiple LSMs, including JSBACH, JULES, ORCHIDEE, CLM4.5 and LPJ-GUESS. Relationships of interannual variations of modeled surface fluxes to LAI changes have been analyzed at global scale across different climatological gradients and compared with satellite-based products. A set of scoring metrics has been used to assess the overall model performances and a detailed analysis in the climate space has been provided to diagnose possible model errors associated to background conditions. Results have enabled us to identify model-specific strengths and deficiencies. An overall best performing model does not emerge from the analyses. However, the comparison with other models that work better under certain metrics and conditions indicates that improvements are expected to be potentially achievable. A general amplification of the biophysical processes mediated by vegetation is found across the different land surface schemes. Grasslands are characterized by an underestimated year-to-year variability of LAI in cold climates, ultimately affecting the amount of absorbed radiation. In addition patterns of simulated turbulent fluxes appear opposite to observations. Such systematic errors shed light on the current partial understanding of some of the mechanisms controlling the surface energy balance. In contrast forests appear reasonably well represented with respect to the interactions between LAI and turbulent fluxes across most climatological gradients, while for net radiation this is only true for warm climates. These proven strengths increase the confidence on how certain processes are simulated in LSMs. The model capacity to mimic the vegetation-biophysics interplay has been tested over the real scenario of greening that occurred in the last 30 years. We found that the modeled trends in surface heat fluxes associated with the long-term changes in leaf area could vary largely from those observed, with different discrepancies across models and climate zones. Our findings help to identify knowledge gaps and improve model representation of the sensitivity of biophysical processes to changes in leaf area density. In particular, comparing models and observations over a wide range of climate and vegetation conditions, as analyzed here, allowed capturing non-linearity of system responses that may emerge more frequently in future climate scenarios.
Modelling land-atmosphere interactions in tropical African wetlands
NASA Astrophysics Data System (ADS)
Dadson, S.
2012-04-01
Wetlands interact with the climate system in two ways. First, the availability of water at the land surface introduces important feedbacks on climate via surface fluxes of energy and water [1]. Over wet surfaces, high daytime evaporation rates and suppressed sensible heat fluxes induce a shallower, moister planetary boundary layer, which affects atmospheric instability and favours the initiation of new storms [2]. Second, wetlands form a key link between the hydrological and carbon cycles, via anoxic degradation of organic matter to release methane (CH4). Wetlands are the largest, but least well quantified, single source of CH4, with recent emission estimates ranging from 105-278 Tg yr-1, ~75% of which comes from the tropics [3]. Although the emissions of methane from boreal wetlands and lakes are less than those from tropical wetlands [3], their size and remoteness pose significant challenges to the quantification of their feedbacks to regional and global climate. In this paper, I present a summary of recent work on modelling hydrological and biogeochemical aspects of wetland formation and the associated land-atmosphere feedbacks in African and boreal environments. We have added an overbank inundation model to the Joint UK Land Environment Simulator (JULES). Sub-grid topographic data were used to derive a two-parameter frequency distribution of inundated areas. Our predictions of inundated area are in good agreement with observed estimates of the extent of inundation obtained using satellite infrared and microwave remote sensing [4,5]. The model predicts significant evaporative losses from the inundated region accounting for doubling of the total land-atmosphere water flux during periods of greatest flooding. I also present new parameterisations of methane generation from wetlands. 1. Koster, R.D., et al., 2004, Science, 305(5687): 1138-40. 2. Taylor, C.M., 2010, Geophys. Res. Lett., 37: L05406. 3. US EPA, 2010, Methane and Nitrous Oxide Emissions From Natural Sources, Report EPA 430-R-10-001. 4. S.J. Dadson, et al., 2010, Journal of Geophysical Research, 115, D23114 5. F. Papa, et al., 2010, Journal of Geophysical Research, 115, D12111, doi:10.1029/2009JD012674.
Volkov and Kononenko in the ATV during Expedition 17
2008-05-12
ISS017-E-006544 (12 May 2008) --- Russian Federal Space Agency cosmonauts Sergei Volkov (left), Expedition 17 commander, and Oleg Kononenko, flight engineer, take a moment for a photo in the Jules Verne Automated Transfer Vehicle (ATV) while it remains docked with the International Space Station.
Volkov and Kononenko in the ATV during Expedition 17
2008-05-12
ISS017-E-006543 (12 May 2008) --- Russian Federal Space Agency cosmonauts Sergei Volkov (bottom), Expedition 17 commander, and Oleg Kononenko, flight engineer, take a moment for a photo in the Jules Verne Automated Transfer Vehicle (ATV) while it remains docked with the International Space Station.
Why Our Nation Tolerates Risks to Children.
ERIC Educational Resources Information Center
Penning, Nick
1991-01-01
Contrasts children's well-being and family support services in the United States with superior programs in Germany and other industrialized countries. The American Association of School Administrators considers the Children's Investment Trust, authored by Head Start founding administrator Jule Sugarman, an absolute must for improving children's…
NASA Astrophysics Data System (ADS)
Agrawal, Shubhi; Chakraborty, Arindam; Karmakar, Nirupam; Moulds, Simon; Mijic, Ana; Buytaert, Wouter
2017-04-01
Decreasing trend in rainfall in the last few decades over Indo-Gangetic Plains of northern India as seen from ground-based observations, parallels stressed ground water resources, with irrigation utilising up to 90%. The decrease in mean rainfall is co-incidental with an increasing trend in irrigation. In this work, we have analysed the effect of the extensive irrigation over Gangetic Plains (GP) on monsoon climate. In the first step, the effect of irrigation on soil moisture was accessed using a high-resolution land surface model (JULES). The model was run over Gangetic basin in two scenarios: with and without irrigation. It was seen that the mean soil moisture over GP in the irrigated scenario is higher as compared to non-irrigated scenario. These soil moisture fields were then used as forcing to a state-of-the-art general circulation model with realistic land-atmosphere coupling. A decrease in June-September precipitation over GP, significant at 95% level, is noted in the model simulation with irrigation as compared to simulation without irrigation. In specific, these changes show a remarkable similarity to the long-term trend in observed rainfall spatial pattern. Moreover, weakening of the variability of intra-seasonal oscillations in the high (10-20 days) and low (30-60 days) frequency bands is noted with irrigation. Our results suggest that with shrinking ground water resources in the GP region and a decline in the summer precipitation, the water crisis could exacerbate, with irrigation contributing in a positive feedback mechanism on these tendencies.
Quantifying the impact of land use change on hydrological responses in the Upper Ganga Basin, India
NASA Astrophysics Data System (ADS)
Tsarouchi, Georgia-Marina; Mijic, Ana; Moulds, Simon; Chawla, Ila; Mujumdar, Pradeep; Buytaert, Wouter
2013-04-01
Quantifying how changes in land use affect the hydrological response at the river basin scale is a challenge in hydrological science and especially in the tropics where many regions are considered data sparse. Earlier work by the authors developed and used high-resolution, reconstructed land cover maps for northern India, based on satellite imagery and historic land-use maps for the years 1984, 1998 and 2010. Large-scale land use changes and their effects on landscape patterns can impact water supply in a watershed by altering hydrological processes such as evaporation, infiltration, surface runoff, groundwater discharge and stream flow. Three land use scenarios were tested to explore the sensitivity of the catchment's response to land use changes: (a) historic land use of 1984 with integrated evolution to 2010; (b) land use of 2010 remaining stable; and (c) hypothetical future projection of land use for 2030. The future scenario was produced with Markov chain analysis and generation of transition probability matrices, indicating transition potentials from one land use class to another. The study used socio-economic (population density), geographic (distances to roads and rivers, and location of protected areas) and biophysical drivers (suitability of soil for agricultural production, slope, aspect, and elevation). The distributed version of the land surface model JULES was integrated at a resolution of 0.01° for the years 1984 to 2030. Based on a sensitivity analysis, the most sensitive parameters were identified. Then, the model was calibrated against measured daily stream flow data. The impact of land use changes was investigated by calculating annual variations in hydrological components, differences in annual stream flow and surface runoff during the simulation period. The land use changes correspond to significant differences on the long-term hydrologic fluxes for each scenario. Once analysed from a future water resources perspective, the results will be beneficial in constructing decision support tools for regional land-use planning and management.
New York area and worldwide: call-in radio program on HIV.
1999-07-16
Treatment activist Jules Levin, founder of the National AIDS Treatment Advocacy Group, has begun a weekly radio program called "Living Well with HIV". Listeners can call in with questions for experts featured on the show. Programs on hepatitis and AIDS have already been scheduled. Contact information is provided.
Volkov and Kononenko with the stowage bags in the ATV during Expedition 17
2008-05-12
ISS017-E-006545 (12 May 2008) --- Russian Federal Space Agency cosmonauts Sergei Volkov (left), Expedition 17 commander, and Oleg Kononenko, flight engineer, work with stowage bags in the Jules Verne Automated Transfer Vehicle (ATV) while it remains docked with the International Space Station.
ATV during Demonstration Day 2 Rendezvous Test
2008-03-31
ISS016-E-034177 (31 March 2008) --- Backdropped by the blackness of space, the Jules Verne Automated Transfer Vehicle (ATV) approaches the International Space Station on Monday, March 31, 2008, for its "Demo Day 2" practice maneuvers. It moved to within 36 feet of the Zvezda Service Module in a rehearsal for docking on Thursday.
2012-08-03
CAPE CANAVERAL, Fla. – Charles Bolden, NASA administrator, center, is shown the high bay at the Operations and Checkout Building at NASA's Kennedy Space Center in Florida by NASA's Scott Wilson, left, and Lockheed Martin's Jules Schneider, right. Lockheed Martin is processing an Orion spacecraft that will make an uncrewed flight test in 2014. Photo credit: NASA/Kim Shifflett
2012-08-03
CAPE CANAVERAL, Fla. – Charles Bolden, NASA administrator, center, is shown the high bay at the Operations and Checkout Building at NASA's Kennedy Space Center in Florida by NASA's Scott Wilson, left, and Lockheed Martin's Jules Schneider, foreground. Lockheed Martin is processing an Orion spacecraft that will make an uncrewed flight test in 2014. Photo credit: NASA/Kim Shifflett
ERIC Educational Resources Information Center
Haney, Walt
Three do-it-yourself intelligence test handbooks, five mini-textbooks, and five consumer protection guides are reviewed. Each type of publication reflects different social ideologies and communicates favorable, cautiously neutral, or critical messages, respectively, about testing. Psychologists Jules Leopold, Martin Lutterjohan, and Victor…
ATV during Demonstration Day 2 Rendezvous Test
2008-03-31
ISS016-E-034176 (31 March 2008) --- Backdropped by the blackness of space, the Jules Verne Automated Transfer Vehicle (ATV) approaches the International Space Station on Monday, March 31, 2008, for its "Demo Day 2" practice maneuvers. It moved to within 36 feet of the Zvezda Service Module in a rehearsal for docking on Thursday.
Experimental validation of photon-heating calculation for the Jules Horowitz Reactor
NASA Astrophysics Data System (ADS)
Lemaire, M.; Vaglio-Gaudard, C.; Lyoussi, A.; Reynard-Carette, C.; Di Salvo, J.; Gruel, A.
2015-04-01
The Jules Horowitz Reactor (JHR) is the next Material-Testing Reactor (MTR) under construction at CEA Cadarache. High values of photon heating (up to 20 W/g) are expected in this MTR. As temperature is a key parameter for material behavior, the accuracy of photon-heating calculation in the different JHR structures is an important stake with regard to JHR safety and performances. In order to experimentally validate the calculation of photon heating in the JHR, an integral experiment called AMMON was carried out in the critical mock-up EOLE at CEA Cadarache to help ascertain the calculation bias and its associated uncertainty. Nuclear heating was measured in different JHR-representative AMMON core configurations using ThermoLuminescent Detectors (TLDs) and Optically Stimulated Luminescent Detectors (OSLDs). This article presents the interpretation methodology and the calculation/experiment (C/E) ratio for all the TLD and OSLD measurements conducted in AMMON. It then deals with representativeness elements of the AMMON experiment regarding the JHR and establishes the calculation biases (and its associated uncertainty) applicable to photon-heating calculation for the JHR.
Future Projections of ENSO and Drought (Invited)
NASA Astrophysics Data System (ADS)
Cane, M. A.
2009-12-01
Jule Charney, who was my advisor, worked very broadly - and profoundly - on climate dynamics. In this discussion of the present state of knowledge I will focus on two aspects of climate that I view as legacies of his work: our ability to project climate variability in the tropics and to project drought. (I have in mind his work with Shukla on predictability of monsoons, and Charney 1975, Dynamics of deserts and drought in the Sahel., Q. J. Roy. Meteor. Soc., 101, 193-202). First, I will consider the projections of ENSO (El Niño and Southern Oscillation) in a warming world. (My own interest in ENSO was piqued in discussions with Charney and others during the ENSO-influenced blocking events in the late 1970s; in good measure, the approach I took to understanding and modeling ENSO was based in my thesis work.) Current IPCC models differ markedly in their projections of the mean state of the equatorial Pacific, some favoring a more “El Niño- like”, some the opposite. Possible reasons for these disagreements will be considered in the light of our understanding of ENSO and tropical climate more generally. Observational data for the past century and a half will figure prominently. Droughts in the US Southwest have a strong ENSO signal, but IPCC models are fairly consistent in projecting enhanced drought there. The reasons for this will be discussed. Models are less consistent in their predictions of the future Sahel. I will discuss what is understood about causes of drought in the Sahel, which appear to point toward sea surface temperature as the controlling influence, in contrast to Charney’s albedo hypothesis.
Reach for the Stars: Visions for Literacy Coaching Programs
ERIC Educational Resources Information Center
DeFord, Diane
2012-01-01
This brief by the Literacy Coaching Clearinghouse is about reaching for the stars--stories of vision and commitment from educators in small and large schools. Everyone knows of people who are held up as "visionaries" throughout history: Leonardo Da Vinci, Mahatma Gandhi, Jules Verne, Thomas Edison, Susan Anthony, or John Dewey, to name a few. The…
Jules Verne's "Around the World in Eighty Days": Helping Teach the National Geography Standards
ERIC Educational Resources Information Center
Donaldson, Daniel P.; Kuhlke, Olaf
2009-01-01
Consistent with developments in American education pedagogy, geography educators have made great strides exploring a wide range of high- and low-tech methods for teaching and learning geographic concepts. This article draws on a qualitative analysis of essays in which college students discuss tenets of the National Geography Standards in the…
"Does Broca's Area Exist?:" Christofredo Jakob's 1906 Response to Pierre Marie's Holistic Stance
ERIC Educational Resources Information Center
Tsapkini, Kyrana; Vivas, Ana B.; Triarhou, Lazaros C.
2008-01-01
In 1906, Pierre Marie triggered a heated controversy and an exchange of articles with Jules Dejerine over the localization of language functions in the human brain. The debate spread internationally. One of the timeliest responses, that appeared in print 1 month after Marie's paper, came from Christofredo Jakob, a Bavarian-born neuropathologist…
2012-08-03
CAPE CANAVERAL, Fla. – Lockheed Martin's Jules Schneider, right, shows details of the preparation hardware used for the Orion capsule to Charles Bolden, NASA administrator, center. The Orion capsule will make an uncrewed flight test in 2014. The spacecraft is in the high bay at the Operations and Checkout Building at NASA's Kennedy Space Center in Florida. Photo credit: NASA/Kim Shifflett
ERIC Educational Resources Information Center
Adult Literacy and Basic Skills Unit, London (England).
This document, one of a series of British occasional papers on basic education, investigates adult literacy practices in Africa, Asia, Latin America, and the Caribbean. The texts and their authors are "Building a National Movement: The Caribbean Experience" (Didacus Jules); "Literacy and Empowerment: A Definition for Literacy"…
Invest in Children Today for a Work Force Tomorrow.
ERIC Educational Resources Information Center
Penning, Nick
1989-01-01
To confront the growing proportion of disadvantaged children amidst the shrinking pool of future workers, Jule Sugarman (Washington State Secretary of Social and Health Services) has proposed a Children's Trust to fund existing and new programs for children. The program would be funded by a .3 percent payroll tax for both employers and employees.…
SPACE TODAY ONLINE - Space Today Online covering Space from Earth to the
Space Rockets 300 Flights Delta Proton Search for Meteorites American Weather Satellites Artist concept Rockets: Spaceports Plowshares 21st Century Experimental Europe's Vega Brazil's Difficulties U.S. Delta 4 , Atlas 5 America's 300th Delta Russia's 300th Proton Spaceflight Museum Space Station: Jules Verne Cargo
The Film. The Bobbs-Merrill Series in Composition and Rhetoric.
ERIC Educational Resources Information Center
Sarris, Andrew, Ed.
Prefaced by a brief discussion of early films and film criticism, 10 essays treat selected modern directors and their works. Essays on Stanley Kubrick's "Lolita," the early works of Elia Kazan, and the response of French critics to Jerry Lewis explore the American scene, while Francois Truffaut's "Jules and Jim," the early work of Robert Bressen,…
2012-08-03
CAPE CANAVERAL, Fla. – Lockheed Martin's Jules Schneider, right, shows the upper portion of the Orion capsule to Charles Bolden, NASA administrator, center, as NASA's Scott Wilson looks on. The Orion capsule will make an uncrewed flight test in 2014. The spacecraft is in the high bay at the Operations and Checkout Building at NASA's Kennedy Space Center in Florida. Photo credit: NASA/Kim Shifflett
2012-08-03
CAPE CANAVERAL, Fla. – Lockheed Martin's Jules Schneider, right, shows the upper portion of the Orion capsule to Charles Bolden, NASA administrator, center, as NASA's Scott Wilson looks on. The Orion capsule will make an uncrewed flight test in 2014. The spacecraft is in the high bay at the Operations and Checkout Building at NASA's Kennedy Space Center in Florida. Photo credit: NASA/Kim Shifflett
ATV during Demonstration Day 2 Rendezvous Test
2008-03-31
ISS016-E-034191 (31 March 2008) --- Backdropped by the airglow of Earth's horizon and the blackness of space, the Jules Verne Automated Transfer Vehicle (ATV) approaches the International Space Station on Monday, March 31, 2008, for its "Demo Day 2" practice maneuvers. It moved to within 36 feet of the Zvezda Service Module in a rehearsal for docking on Thursday.
ERIC Educational Resources Information Center
New York State Education Dept., Albany. Div. for Handicapped Children.
Six speeches given at an institute on reading programs for emotionally handicapped children are presented. Jules Abrams first examines the relationship of emotional and personality maladjustments to reading difficulty. Then Clifford Kolson advocates the promotion of informal reading and the proper diagnosis of a child's reading level. A discussion…
ERIC Educational Resources Information Center
Duchess County Board of Cooperative Educational Services, NY.
The conference proceedings include seven papers dealing with reading problems of emotionally disturbed children. Emotional resistance to reading is discussed by Jules Abrams, a psychiatrist. The purposes of testing and the problem of labeling are touched upon by Clifford Kolson. Some practical suggestions of classroom techniques for combining a…
What Is Steampunk, and Do I Want It in My Library?
ERIC Educational Resources Information Center
Rozmus, Emily
2011-01-01
What is steampunk? Most call it Victorian science fiction. Steampunk can claim such authors as H.G. Wells and Jules Verne as its earliest writers. These two Victorian/Edwardian era writers created steampunk settings in books such as "The Time Machine" and "Journey to the Center of the Earth". In the 1990s, writers such as William Gibson, Bruce…
The role of history in teaching science — A case study
NASA Astrophysics Data System (ADS)
Hendrick, Robert M.
1992-06-01
One of the most interesting aspects of late-nineteenth-century France was the extraordinary interest the public expressed in science. Its adulation of Pasteur was only one of the many manifestations of this interest. It was also expressed in the widespread popularity of scientists as public figures and in the increasing public and private financial support of science. While popularity of science was created in the general public by fiction and by the various international ‘world fairs’ held in Paris, it was strongest and most important in the middle classes. This paper examines one of the key methods used to stimulate bourgeois interest in science in France during the Second Empire and early Third Republic (1852 1895): the campaign to create a science vulgarisée, a popularized science. While a number of different approaches used by these popularizers are examined, the article concentrates on the ‘science writings’ of Jules Michelet and Jules Verne, both of whom were immensely successful in creating a favorable climate of opinion for French science. The article concludes by suggesting how such an approach could be modernized and utilized in order to create greater scientific literacy and a similar acceptance by the public today.
Jules Verne's Journey to the centre of the Earth: the secret of counterdepressive narratives.
Sanchez-Cardenas, Michel
2005-12-01
The author interprets Jules Verne's Journey to the centre of the Earth with the help of Matte Blanco's theoretical framework, which describes the principle of symmetry and the principle of generalization. The first states that, from the moment an element or a proposition becomes conscious, it coexists in the unconscious with its symmetrically opposite form. The second refers to the confusion of elements once they have been apprehended by thought as containing a common point; they are put into larger and larger groups which merge into an indivisible whole. Verne's novel is built on paired elements which become symmetrized (e.g. distinct minerals vs molten lava; scientific rationality vs madness; the living vs the dead, etc.). These elements in turn become confused with one another, thanks largely to the novel's atmosphere of oral incorporation. This allows the fusion between subject and object, and, in particular, between the orphaned hero and his dead (Earth) mother. The novel's narrative evolution through three stages (separation, fusion and de-fusion, which are paralleled by rational, irrational and rational thought) can thus be understood as a mourning process. Similar processes can be found in other literary works.
Walusinski, O
2017-03-01
World War I (1914-1918), however tragic, was nonetheless an "edifying school of nervous system experimental pathology" not only because of the various types of injuries, but also because their numbers were greater than any physician could have foreseen. The peripheral nervous system, the spine and the brain were all to benefit from the subsequent advances in clinical and anatomo-functional knowledge. Neurosurgeons took on nerve sutures, spinal injury exploration, and the localization and extraction of intracranial foreign bodies. Little by little, physical medicine and rehabilitation were established. A few of the most famous Parisian neurologists at the time-Jules and Augusta Dejerine, Pierre Marie, Joseph Babiński and Georges Guillain, who directed the military neurology centers-took up the physically and emotionally exhausting challenge of treating thousands of wounded soldiers. They not only cared for them, but also studied them scientifically, with the help of a small but devoted band of colleagues. The examples presented here reveal their courage and their efforts to make discoveries for which we remain grateful today. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
NASA Astrophysics Data System (ADS)
Marthews, T.; Malhi, Y.; Girardin, C.; Silva-Espejo, J.; Aragão, L.; Metcalfe, D.; Rapp, J.; Mercado, L.; Fisher, R.; Galbraith, D.; Fisher, J.; Salinas-Revilla, N.; Friend, A.; Restrepo-Coupe, N.; Williams, R.
2012-04-01
A better understanding of the mechanisms controlling the magnitude and sign of carbon components in tropical forest ecosystems is important for reliable estimation of this important regional component of the global carbon cycle. We used the JULES vegetation model to simulate all components of the carbon balance at six sites along an Andes-Amazon transect across Peru and Brazil and compared the results to published field measurements. In the upper montane zone the model predicted a vegetation dieback, indicating a need for better parameterisation of cloud forest vegetation. In the lower montane and lowland zones simulated ecosystem productivity and respiration were predicted with reasonable accuracy, although not always within the error bounds of the observations. Model-predicted carbon use efficiency in this transect surprisingly did not increase with elevation, but remained close to the 'temperate' value 0.5. This may be explained by elevational changes in the balance between growth and maintenance respiration within the forest canopy, as controlled by both temperature- and pressure-mediated processes.
Fuel moisture content estimation: a land-surface modelling approach applied to African savannas
NASA Astrophysics Data System (ADS)
Ghent, D.; Spessa, A.; Kaduk, J.; Balzter, H.
2009-04-01
Despite the importance of fire to the global climate system, in terms of emissions from biomass burning, ecosystem structure and function, and changes to surface albedo, current land-surface models do not adequately estimate key variables affecting fire ignition and propagation. Fuel moisture content (FMC) is considered one of the most important of these variables (Chuvieco et al., 2004). Biophysical models, with appropriate plant functional type parameterisations, are the most viable option to adequately predict FMC over continental scales at high temporal resolution. However, the complexity of plant-water interactions, and the variability associated with short-term climate changes, means it is one of the most difficult fire variables to quantify and predict. Our work attempts to resolve this issue using a combination of satellite data and biophysical modelling applied to Africa. The approach we take is to represent live FMC as a surface dryness index; expressed as the ratio between the Normalised Difference Vegetation Index (NDVI) and land-surface temperature (LST). It has been argued in previous studies (Sandholt et al., 2002; Snyder et al., 2006), that this ratio displays a statistically stronger correlation to FMC than either of the variables, considered separately. In this study, simulated FMC is constrained through the assimilation of remotely sensed LST and NDVI data into the land-surface model JULES (Joint-UK Land Environment Simulator). Previous modelling studies of fire activity in Africa savannas, such as Lehsten et al. (2008), have reported significant levels of uncertainty associated with the simulations. This uncertainty is important because African savannas are among some of the most frequently burnt ecosystems and are a major source of greenhouse trace gases and aerosol emissions (Scholes et al., 1996). Furthermore, regional climate model studies indicate that many parts of the African savannas will experience drier and warmer conditions in future (IPCC 2007). The simulation of realistic fire disturbance regimes with biophysical and biogeochemical models is a prerequisite for reducing the uncertainty of the African carbon cycle, and the feedbacks associated with this cycle and the global climate system. Using multi-temporal modelling analysis techniques, we present preliminary results that provide a more robust estimation of live FMC. References Chuvieco, E., Aguado, I. and Dimitrakopoulos, A. P. (2004) Conversion of fuel moisture content values to ignition potential for integrated fire danger assessment. Canadian Journal of Forest Research-Revue Canadienne De Recherche Forestiere 34(11): 2284-2293. IPCC (2007) 'Climate Change 2007: Synthesis Report. Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, Pachauri, R.K and Reisinger, A. (eds.)].' IPCC, (Geneva, Switzerland). Lehsten, V., Tansey, K. J., Balzter, H, Thonicke, K., Spessa, A., Weber, U., Smith, B., and Arneth, A. (2008). Estimating carbon emissions from African wildfires. Accepted Biogeosciences. Sandholt, I., Rasmussen, K. & Andersen, J. (2002) A simple interpretation of the surface temperature/vegetation index space for assessment of surface moisture status. Remote Sensing of Environment 79(2-3): 213-224. Scholes, R. J., Ward, D. E. and Justice, C. O. (1996) Emissions of trace gases and aerosol particles due to vegetation burning in southern hemisphere Africa. Journal of Geophysical Research-Atmospheres 101(D19): 23677-23682. Snyder, R. L., Spano, D., Duce, P., Baldocchi, D., Xu, L. K. & Kyaw, T. P. U. (2006) A fuel dryness index for grassland fire-danger assessment. Agricultural and Forest Meteorology 139(1-2): 1-11.
NASA Astrophysics Data System (ADS)
Duveiller, Gregory; Forzieri, Giovanni; Robertson, Eddy; Georgievski, Goran; Li, Wei; Lawrence, Peter; Ciais, Philippe; Pongratz, Julia; Sitch, Stephen; Wiltshire, Andy; Arneth, Almut; Cescatti, Alessandro
2017-04-01
Changes in vegetation cover can affect the climate by altering the carbon, water and energy cycles. The main tools to characterize such land-climate interactions for both the past and future are land surface models (LSMs) that can be embedded in larger Earth System models (ESMs). While such models have long been used to characterize the biogeochemical effects of vegetation cover change, their capacity to model biophysical effects accurately across the globe remains unclear due to the complexity of the phenomena. The result of competing biophysical processes on the surface energy balance varies spatially and seasonally, and can lead to warming or cooling depending on the specific vegetation change and on the background climate (e.g. presence of snow or soil moisture). Here we present a global scale benchmarking exercise of four of the most commonly used LSMs (JULES, ORCHIDEE, JSBACH and CLM) against a dedicated dataset of satellite observations. To facilitate the understanding of the causes that lead to discrepancies between simulated and observed data, we focus on pure transitions amongst major plant functional types (PFTs): from different tree types (evergreen broadleaf trees, deciduous broadleaf trees and needleleaf trees) to either grasslands or crops. From the modelling perspective, this entails generating a separate simulation for each PFT in which all 1° by 1° grid cells are uniformly covered with that PFT, and then analysing the differences amongst them in terms of resulting biophysical variables (e.g net radiation, latent and sensible heat). From the satellite perspective, the effect of pure transitions is obtained by unmixing the signal of different 0.05° spatial resolution MODIS products (albedo, latent heat, upwelling longwave radiation) over a local moving window using PFT maps derived from the ESA Climate Change Initiative land cover map. After aggregating to a common spatial support, the observation and model-driven datasets are confronted and analysed across different climate zones. Results indicate that models tend to catch better radiative than non-radiative energy fluxes. However, for various vegetation transitions, models do not agree amongst themselves on the magnitude nor the sign of the change. In particular, predicting the impact of land cover change on the partitioning of the available energy between latent and sensible heat proves to be a challenging task for vegetation models. We expect that this benchmarking exercise will shed a light on where to prioritize the efforts in model development as well as inform where consensus between model and observations is already met. Improving the robustness and consistency of land-model is essential to develop and inform land-based mitigation and adaptation policies that account for both biogeochemical and biophysical vegetation impacts on climate.
NASA Astrophysics Data System (ADS)
Churkina, G.; Zahle, S.; Hughes, J.; Viovy, N.; Chen, Y.; Jung, M.; Ramankutty, N.; Roedenbeck, C.; Heimann, M.; Jones, C.
2009-12-01
In Europe, atmospheric nitrogen deposition has more than doubled, air temperature was rising, forest cover was steadily increasing, while agricultural area was declining over the last 50 years. What effect have these changes had on the European carbon balance? In this study we estimate responses of the European land ecosystems to nitrogen deposition, rising CO2, land cover conversion and climate change. We use results from three ecosystem process models such as BIOME-BGC, JULES, and ORCHIDEE (-CN) to address this question. We discuss to which degree carbon balance of Europe has been altered by nitrogen deposition in comparison to other drivers and identify areas which carbon balance has been affected by anthropogenic changes the most. We also analyze ecosystems carbon pools which were affected by the abovementioned environmental changes.
NASA Astrophysics Data System (ADS)
Verhoef, Anne; Egea, Gregorio; Garrigues, Sebastien; Vidale, Pier Luigi; Balan Sarojini, Beena
2017-04-01
Current land surface schemes in many crop, weather and climate models make use of the coupled photosynthesis-stomatal conductance (A-gs) models of plant function to determine the transpiration flux and gross primary productivity. Vegetation exchange is controlled by many environmental factors, and soil moisture control on root water uptake and stomatal function is a primary pathway for feedbacks in sub-tropical to temperate ecosystems. Representations of the above process of soil moisture control on plant function (often referred to as a 'beta' factor) vary among models. This matters because the simulated energy, water and carbon balances are very sensitive to the representation of water stress in these models. Building on Egea et al. (2011) and Verhoef and Egea (2014), we tested a range of 'beta' approaches in a leaf-level A-gs model (compatible with models such as JULES, CHTESSEL, ISBA, CLM), as well as some beta-approaches borrowed from the agronomic, and plant physiological communities (a combined soil-plant hydraulic approach, see Verhoef and Egea, 2014). Root zone soil moisture was allowed to limit plant function via individual routes (via CO2 assimilation, stomatal conductance, or mesophyll conductance) as well as combinations of that. The simulations were conducted for a typical Mediterranean field site (Avignon, France; Garrigues et al., 2015) which provides 14 years of near-continuous measurements of soil moisture and atmospheric driving data. Daytime (8-16 hrs local time) data between April-September were used. This allowed a broad range of atmospheric and soil moisture/vegetation states to be explored. A number of crops and tree types were investigated in this way. We evaluated the effect of choice of beta-function for Mediterranean climates in relation to stomatal conductance, transpiration, photosynthesis, and leaf surface temperature. We also studied the implications for a range of widely used agro-/micro-meteorological indicators such as Bowen ratio and the omega decoupling coefficient (which quantifies the degree of the aerodynamic coupling between a vegetated surface and the atmospheric boundary layer; Jacobs and de Bruin, 1992); and applications (e.g. the use of surface temperature based water stress indices). Results showed that choice of 'beta' function has far-reaching consequences. For certain widely used 'beta'-models the predicted key fluxes and state variables, predominantly compared using kernel density functions, showed considerable 'clumping' around narrow data ranges. This will have implications for the strength of land-surface feedback predicted by these models, and for any agrometeorological applications they are used for. Recommendations as to the most suitable 'beta'-functions, and related parameter sets, for Mediterranean climates were made. References Garrigues, S. et al. (2015) Evaluation of land surface model simulations of evapotranspiration over a 12-year crop succession: impact of soil hydraulic and vegetation properties, Hydrol. Earth Syst. Sci., 19, 3109-3131; Jacobs, C. M. J. and de Bruin, H. A. R. (1992) The sensitivity of regional transpiration to land-surface characteristics: Significance of feedback, J. Climate, 5(7), 683-698; Verhoef, A. and Egea, G. (2014) Agriculture and Forest Meteorology, 191, 22-32; Egea, G., Verhoef, A., and Vidale, P. L. (2011) Agricultural and Forest Meteorology, 151, 1370-1384
2008-09-30
European Space Agency's 'Jules Verne' Automated Transfer Vehicle ATV-1 re-entry in Earth's atmosphere over Pacific Ocean. The breakup ad fragmentation of the ESA's ATV-1 was captured in dramatic fashion by scientists aboard NASA's DC-8 airborne laboratory and a Gulfstream V aircraft as it re-entered the atmosphere early Monday morning over the South Pacific. Photo Credit: NASA Ames Research Center/ESA/Jesse Carpenter/Bill Moede
ERIC Educational Resources Information Center
Congress of the U.S., Washington, DC. House Select Committee on Aging.
This paper contains testimony and prepared statements from the Congressional hearing called to examine ways of controlling cancer. Opening statements are included from Representatives Claudine Schneider, Jim Lightfoot, and Ben Blaz. Testimonies are given by Rosemarie Lindgren, a homemaker and former cancer patient, and by Jules Cardin, a patient…
2008-09-30
European Space Agency's 'Jules Verne' Automated Transfer Vehicle ATV-1 re-entry in Earth's atmosphere over Pacific Ocean. The breakup ad fragmentation of the ESA's ATV-1 was captured in dramatic fashion by scientists aboard NASA's DC-8 airborne laboratory and a Gulfstream V aircraft as it re-entered the atmosphere early Monday morning over the South Pacific. Photo Credit: NASA Ames Research Center/ESA/Jesse Carpenter/Bill Moede
2008-09-30
European Space Agency's 'Jules Verne' Automated Transfer Vehicle ATV-1 re-entry in Earth's atmosphere over Pacific Ocean. The breakup ad fragmentation of the ESA's ATV-1 was captured in dramatic fashion by scientists aboard NASA's DC-8 airborne laboratory and a Gulfstream V aircraft as it re-entered the atmosphere early Monday morning over the South Pacific. Photo Credit: NASA Ames Research Center/ESA/Jesse Carpenter/Bill Moede
Installing the new PCE (Proximity Communications Equipment) hardware
2005-06-29
ISS011-E-09799 (27 June 2005) --- Cosmonaut Sergei K. Krikalev, Expedition 11 commander representing Russia's Federal Space Agency, works with the new Proximity Communications Equipment (PCE) hardware of the ASN-M satellite navigation system for the European Automated Transfer Vehicle (ATV) Jules Verne in the Zvezda Service Module of the International Space Station. The ATV is scheduled to arrive at the Station next year.
2008-09-30
European Space Agency's 'Jules Verne' Automated Transfer Vehicle ATV-1 re-entry in Earth's atmosphere over Pacific Ocean. The breakup ad fragmentation of the ESA's ATV-1 was captured in dramatic fashion by scientists aboard NASA's DC-8 airborne laboratory and a Gulfstream V aircraft as it re-entered the atmosphere early Monday morning over the South Pacific. Photo Credit: NASA Ames Research Center/ESA/Jesse Carpenter/Bill Moede
2008-09-30
European Space Agency's 'Jules Verne' Automated Transfer Vehicle ATV-1 re-entry in Earth's atmosphere over Pacific Ocean. The breakup ad fragmentation of the ESA's ATV-1 was captured in dramatic fashion by scientists aboard NASA's DC-8 airborne laboratory and a Gulfstream V aircraft as it re-entered the atmosphere early Monday morning over the South Pacific. Photo Credit: NASA Ames Research Center/ESA/Jesse Carpenter/Bill Moede
ERIC Educational Resources Information Center
Layne, Anthony; Jules, Vena; Kutnick, Peter; Layne, Clarissa
2008-01-01
Studies have shown a positive relationship between a rise in schooling levels and economic production [World Bank, 2005. A Time to Choose: Caribbean Development in the 21st Century. World Bank, Washington, DC; Jules, V., Panneflek, A., 2000. EFA in the Caribbean: Assessment 2000, Sub-Regional Report, vol. 2, The State of Education in the Caribbean…
2008-09-30
European Space Agency's 'Jules Verne' Automated Transfer Vehicle ATV-1 re-entry in Earth's atmosphere over Pacific Ocean. The breakup ad fragmentation of the ESA's ATV-1 was captured in dramatic fashion by scientists aboard NASA's DC-8 airborne laboratory and a Gulfstream V aircraft as it re-entered the atmosphere early Monday morning over the South Pacific. Photo Credit: NASA Ames Research Center/ESA/Jesse Carpenter/Bill Moede
2008-09-30
European Space Agency's 'Jules Verne' Automated Transfer Vehicle ATV-1 re-entry in Earth's atmosphere over Pacific Ocean. The breakup ad fragmentation of the ESA's ATV-1 was captured in dramatic fashion by scientists aboard NASA's DC-8 airborne laboratory and a Gulfstream V aircraft as it re-entered the atmosphere early Monday morning over the South Pacific. Photo Credit: NASA Ames Research Center/ESA/Jesse Carpenter/Bill Moede
2008-09-30
European Space Agency's 'Jules Verne' Automated Transfer Vehicle ATV-1 re-entry in Earth's atmosphere over Pacific Ocean. The breakup ad fragmentation of the ESA's ATV-1 was captured in dramatic fashion by scientists aboard NASA's DC-8 airborne laboratory and a Gulfstream V aircraft as it re-entered the atmosphere early Monday morning over the South Pacific. Photo Credit: NASA Ames Research Center/ESA/Jesse Carpenter/Bill Moede
2008-09-30
European Space Agency's 'Jules Verne' Automated Transfer Vehicle ATV-1 re-entry in Earth's atmosphere over Pacific Ocean. The breakup ad fragmentation of the ESA's ATV-1 was captured in dramatic fashion by scientists aboard NASA's DC-8 airborne laboratory and a Gulfstream V aircraft as it re-entered the atmosphere early Monday morning over the South Pacific. Photo Credit: NASA Ames Research Center/ESA/Jesse Carpenter/Bill Moede
2008-09-30
European Space Agency's 'Jules Verne' Automated Transfer Vehicle ATV-1 re-entry in Earth's atmosphere over Pacific Ocean. The breakup ad fragmentation of the ESA's ATV-1 was captured in dramatic fashion by scientists aboard NASA's DC-8 airborne laboratory and a Gulfstream V aircraft as it re-entered the atmosphere early Monday morning over the South Pacific. Photo Credit: NASA Ames Research Center/ESA/Jesse Carpenter/Bill Moede
2008-09-30
European Space Agency's 'Jules Verne' Automated Transfer Vehicle ATV-1 re-entry in Earth's atmosphere over Pacific Ocean. The breakup ad fragmentation of the ESA's ATV-1 was captured in dramatic fashion by scientists aboard NASA's DC-8 airborne laboratory and a Gulfstream V aircraft as it re-entered the atmosphere early Monday morning over the South Pacific. Photo Credit: NASA Ames Research Center/ESA/Jesse Carpenter/Bill Moede
2008-09-30
European Space Agency's 'Jules Verne' Automated Transfer Vehicle ATV-1 re-entry in Earth's atmosphere over Pacific Ocean. The breakup ad fragmentation of the ESA's ATV-1 was captured in dramatic fashion by scientists aboard NASA's DC-8 airborne laboratory and a Gulfstream V aircraft as it re-entered the atmosphere early Monday morning over the South Pacific. Photo Credit: NASA Ames Research Center/ESA/Jesse Carpenter/Bill Moede
ERIC Educational Resources Information Center
Tschoumy, Jacques-Andre
This document examines the trend of school partnership both inside and outside the educational system. The report asks three questions: what is motivating European partners?; is the phenomenon of partnership really European?; and is this the end of the school of Jules Ferry? School partnership history, strategy, and axiomatics or rules are…
Testing the newly installed PCE (Proximity Communications Equipment) hardware
2005-06-29
ISS011-E-09816 (28 June 2005) --- Cosmonaut Sergei K. Krikalev, Expedition 11 commander representing Russia's Federal Space Agency, tests the newly installed Proximity Communications Equipment (PCE) hardware of the ASN-M satellite navigation system for the European Automated Transfer Vehicle (ATV) Jules Verne in the Zvezda Service Module of the International Space Station. The ATV is scheduled to arrive at the Station next year.
Testing the newly installed PCE (Proximity Communications Equipment) hardware
2005-06-28
ISS011-E-09812 (28 June 2005) --- Cosmonaut Sergei K. Krikalev, Expedition 11 commander representing Russia's Federal Space Agency, tests the newly installed Proximity Communications Equipment (PCE) hardware of the ASN-M satellite navigation system for the European Automated Transfer Vehicle (ATV) Jules Verne in the Zvezda Service Module of the international space station. The ATV is scheduled to arrive at the station next year.
Pioneers of high-speed photography and motion analysis
NASA Astrophysics Data System (ADS)
Haddleton, Graham P.
2005-03-01
In many ways this paper continues from the one presented at the 25th ICHSPP held in Beaune, France in 2002. That paper was on Etienne-Jules Marey, a true pioneer of high speed photographic techniques and cinematography, who was born in Beaune. Whilst researching for that paper the author became fascinated by the efforts and results of many pioneers in the field at the turn of the 19th century.
Sharp and the Jules Verne Launcher
NASA Astrophysics Data System (ADS)
Hunter, John; Cartland, Harry
1996-03-01
Lawrence Livermore National Laboratory (LLNL) has built the worlds largest hydrogen gas gun called SHARP, (Super High Altitude Research Project). Originally designed to launch 5 kg to a 450 km altitude, SHARP is configured horizontally at Site 300 in Tracy, California. SHARP is successfully delivering 5 kg scramjets at Mach 9 in aerophysics tests. Some of the results of the scramjet tests are enlightening and are presented insofar as they are relevant to future launches into space. Using a light gas gun to launch payloads into orbit has been analyzed. We look at LEO (Low Earth Orbit), GEO (Geosynchronous Earth Orbit), and LO (Lunar Orbit). We present a conceptual design for a large light gas gun called the Jules Verne Launcher (JVL). The JVL can deliver 3.3 metric tons to a 500 km low earth orbit. We anticipate one launch per day. We present the history of light gas guns, the SHARP design and performance, and the JVL design. Another section is devoted to the vehicle environment and resultant design. Lastly, we present a cost analysis. Our results indicated that the JVL will be able to deliver 1000 metric tons of payload to LEO yearly. The cost will be 5% of the best US rocket delivery cost. This technology will enable the next phase of man's exploration of space.
Interactive Geophysical Mapping on the Web
NASA Astrophysics Data System (ADS)
Meertens, C.; Hamburger, M.; Estey, L.; Weingroff, M.; Deardorff, R.; Holt, W.
2002-12-01
We have developed a set of interactive, web-based map utilities that make geophysical results accessible to a large number and variety of users. These tools provide access to pre-determined map regions via a simple Html/JavaScript interface or to user-selectable areas using a Java interface to a Generic Mapping Tools (GMT) engine. Users can access a variety of maps, satellite images, and geophysical data at a range of spatial scales for the earth and other planets of the solar system. Developed initially by UNAVCO for study of global-scale geodynamic processes, users can choose from a variety of base maps (satellite mosaics, global topography, geoid, sea-floor age, strain rate and seismic hazard maps, and others) and can then add a number of geographic and geophysical overlays for example coastlines, political boundaries, rivers and lakes, NEIC earthquake and volcano locations, stress axes, and observed and model plate motion and deformation velocity vectors representing a compilation of 2933 geodetic measurements from around the world. The software design is flexible allowing for construction of special editions for different target audiences. Custom maps been implemented for UNAVCO as the "Jules Verne Voyager" and "Voyager Junior", for the International Lithosphere Project's "Global Strain Rate Map", and for EarthScope Education and Outreach as "EarthScope Voyager Jr.". For the later, a number of EarthScope-specific features have been added, including locations of proposed USArray (seismic), Plate Boundary Observatory (geodetic), and San Andreas Fault Observatory at Depth sites plus detailed maps and geographically referenced examples of EarthScope-related scientific investigations. In addition, we are developing a website that incorporates background materials and curricular activities that encourage users to explore Earth processes. A cluster of map processing computers and nearly a terabyte of disk storage has been assembled to power the generation of interactive maps and provide space for a very large collection of map data. A portal to these map tools can be found at: http://jules.unavco.ucar.edu.
A Spectral Evaluation of Models Performances in Mediterranean Oak Woodlands
NASA Astrophysics Data System (ADS)
Vargas, R.; Baldocchi, D. D.; Abramowitz, G.; Carrara, A.; Correia, A.; Kobayashi, H.; Papale, D.; Pearson, D.; Pereira, J.; Piao, S.; Rambal, S.; Sonnentag, O.
2009-12-01
Ecosystem processes are influenced by climatic trends at multiple temporal scales including diel patterns and other mid-term climatic modes, such as interannual and seasonal variability. Because interactions between biophysical components of ecosystem processes are complex, it is important to test how models perform in frequency (e.g. hours, days, weeks, months, years) and time (i.e. day of the year) domains in addition to traditional tests of annual or monthly sums. Here we present a spectral evaluation using wavelet time series analysis of model performance in seven Mediterranean Oak Woodlands that encompass three deciduous and four evergreen sites. We tested the performance of five models (CABLE, ORCHIDEE, BEPS, Biome-BGC, and JULES) on measured variables of gross primary production (GPP) and evapotranspiration (ET). In general, model performance fails at intermediate periods (e.g. weeks to months) likely because these models do not represent the water pulse dynamics that influence GPP and ET at these Mediterranean systems. To improve the performance of a model it is critical to identify first where and when the model fails. Only by identifying where a model fails we can improve the model performance and use them as prognostic tools and to generate further hypotheses that can be tested by new experiments and measurements.
Neutron fluxes in test reactors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Youinou, Gilles Jean-Michel
Communicate the fact that high-power water-cooled test reactors such as the Advanced Test Reactor (ATR), the High Flux Isotope Reactor (HFIR) or the Jules Horowitz Reactor (JHR) cannot provide fast flux levels as high as sodium-cooled fast test reactors. The memo first presents some basics physics considerations about neutron fluxes in test reactors and then uses ATR, HFIR and JHR as an illustration of the performance of modern high-power water-cooled test reactors.
2014-09-10
CAPE CANAVERAL, Fla. – During a ceremony inside the Neil Armstrong Operations and Checkout Building high bay at NASA's Kennedy Space Center in Florida, Jules Schneider, Lockheed Martin Orion Production Operations manager, holds the key to symbolically turn over the Orion spacecraft for Exploration Flight Test-1 to Ground Operations. Waiting to accept the key is Blake Hale, Lockheed Martin Ground Operations manager. Orion is the exploration spacecraft designed to carry astronauts to destinations not yet explored by humans, including an asteroid and Mars. It will have emergency abort capability, sustain the crew during space travel and provide safe re-entry from deep space return velocities. The first unpiloted test flight of the Orion is scheduled to launch atop a United Launch Alliance Delta IV Heavy rocket from Cape Canaveral Air Force Station in Florida in December to an altitude of 3,600 miles above the Earth's surface. The two-orbit, four-hour flight test will help engineers evaluate the systems critical to crew safety including the heat shield, parachute system and launch abort system. For more information, visit http://www.nasa.gov/orion. Photo credit: NASA/Daniel Casper
2014-09-10
CAPE CANAVERAL, Fla. – During a ceremony inside the Neil Armstrong Operations and Checkout Building high bay at NASA's Kennedy Space Center in Florida, Jules Schneider, at right, Lockheed Martin Orion Production Operations manager, presents the key to symbolically turn over the Orion spacecraft for Exploration Flight Test-1 to Ground Operations. Accepting the key is Blake Hale, Lockheed Martin Ground Operations manager. Orion is the exploration spacecraft designed to carry astronauts to destinations not yet explored by humans, including an asteroid and Mars. It will have emergency abort capability, sustain the crew during space travel and provide safe re-entry from deep space return velocities. The first unpiloted test flight of the Orion is scheduled to launch atop a United Launch Alliance Delta IV Heavy rocket from Cape Canaveral Air Force Station in Florida in December to an altitude of 3,600 miles above the Earth's surface. The two-orbit, four-hour flight test will help engineers evaluate the systems critical to crew safety including the heat shield, parachute system and launch abort system. For more information, visit http://www.nasa.gov/orion. Photo credit: NASA/Daniel Casper
2014-09-10
CAPE CANAVERAL, Fla. – Inside the Neil Armstrong Operations and Checkout Building high bay at NASA's Kennedy Space Center in Florida, Jules Schneider, at right, Lockheed Martin Orion Production Operations manager, speaks to NASA and Lockheed Martin workers during a ceremony to turn over the Orion spacecraft for Exploration Flight Test-1 to Ground Operations. At left is Blake Hale, Lockheed Martin Ground Operations manager. Orion is the exploration spacecraft designed to carry astronauts to destinations not yet explored by humans, including an asteroid and Mars. It will have emergency abort capability, sustain the crew during space travel and provide safe re-entry from deep space return velocities. The first unpiloted test flight of the Orion is scheduled to launch atop a United Launch Alliance Delta IV Heavy rocket from Cape Canaveral Air Force Station in Florida in December to an altitude of 3,600 miles above the Earth's surface. The two-orbit, four-hour flight test will help engineers evaluate the systems critical to crew safety including the heat shield, parachute system and launch abort system. For more information, visit http://www.nasa.gov/orion. Photo credit: NASA/Daniel Casper
2014-09-10
CAPE CANAVERAL, Fla. – Inside the Neil Armstrong Operations and Checkout Building high bay at NASA's Kennedy Space Center in Florida, Jules Schneider, at right, Lockheed Martin Orion Production Operations manager, shakes hands with Blake Hale, Lockheed Martin Ground Operations manager, during a ceremony to officially turn over the Orion spacecraft for Exploration Flight Test-1 to Lockheed Martin Ground Operations. Orion is the exploration spacecraft designed to carry astronauts to destinations not yet explored by humans, including an asteroid and Mars. It will have emergency abort capability, sustain the crew during space travel and provide safe re-entry from deep space return velocities. The first unpiloted test flight of the Orion is scheduled to launch atop a United Launch Alliance Delta IV Heavy rocket from Cape Canaveral Air Force Station in Florida in December to an altitude of 3,600 miles above the Earth's surface. The two-orbit, four-hour flight test will help engineers evaluate the systems critical to crew safety including the heat shield, parachute system and launch abort system. For more information, visit http://www.nasa.gov/orion. Photo credit: NASA/Daniel Casper
NASA Astrophysics Data System (ADS)
Spessa, A.; Fisher, R.
2009-04-01
The simulation of fire-vegetation feedbacks is crucial for determining fire-induced changes to ecosystem structure and function, and emissions of trace gases and aerosols under future climate change. A new global fire model SPITFIRE (SPread and InTensity of FIRE) has been designed to overcome many of the limitations in existing fire models set within DGVM frameworks (Thonicke et al. 2008). SPITFIRE has been applied in coupled mode globally (Thonicke et al. 2008) and northern Australia (Spessa et al. unpubl.) as part of the LPJ DGVM. It has also been driven with MODIS burnt area data applied to sub-Saharan Africa (Lehsten et al. 2008) as part of the LPJ-GUESS vegetation model (Smith et al. 2001). Recently, Spessa & Fisher (unpubl.) completed the coupling of SPIFTIRE to the Ecosystem Demography (ED) model (Moorecroft et al. 2001), which has been globalised by Dr R. Fisher as part of the development of the new land surface scheme JULES (Joint UK Environment Simulator) within the QUEST Earth System Model (http://www.quest-esm.ac.uk/). In contrast to the LPJ DGVM, ED is a ‘size and age structured' approximation of an individual based gap model. The major innovation of the ED-SPITFIRE model compared with LPJ-SPITFIRE is the categorisation of each climatic grid cell into a series of non-spatially contiguous patches which are defined by a common ‘age since last disturbance'. In theory, the age-class structure of ED facilitates ecologically realistic processes of succession and re-growth to be represented. By contrast, LPJ DGVM adopts an ‘area-based approach' that implicitly averages individual and patch differences across a wider area and across ‘populations' of PFTs. This presentation provides an overview of SPITFIRE, and provides preliminary results from ED-SPITFIRE applied to northern Australian savanna ecosystems which, due to spatio-temporal variation in fire disturbance, comprise a patchwork of grasses and trees at different stages of post-fire succession. Comparisons with similar simulations undertaken with LPJ-SPITFIRE are also presented.
The Antiaircraft Journal. Volume 94, Number 2, March-April 1951
1951-04-01
are covered in detail. Included under a miscellaneous heading are such topics as the Geneva Conven- tion and extracts from the .United Na- tions Charter...serve as a review for many of the principles associated with guided missiles. They originally were presented in the May 1950 issue of Oil -Power...published by Socony-Vacuum Oil Company, Inc. Hats off to H. G. Wells and Jules Verne! As juvenile readers, most of us thrilled to their seemingly fantastic
Julie Payette and Tamara Jernigan in FGB/Zarya module
2017-04-20
S96-E-5161 (2 June 1999) --- Astronauts Jule Payette (left) and Tamara E. Jernigan, mission specialists, participate in the final hours of tasks designed to prepare the International Space Station (ISS) for business. Here, on the Russian-built Zarya module, the two are seen with a small part of the supplies brought up by the Space Shuttle Discovery. The photo was taken with an electronic still camera (ESC) at 05:58:37 GMT, June 2, 1999.
Reflections on the Conception, Birth, and Childhood of Numerical Weather Prediction
NASA Astrophysics Data System (ADS)
Lorenz, Edward N.
2006-05-01
In recognition of the contributions of Norman Phillips and Joseph Smagorinsky to the field of numerical weather prediction (NWP), a symposium was held in 2003; this account is an amplification of a talk presented there. Ideas anticipating the advent of NWP, the first technically successful numerical weather forcast, and the subsequent progression of NWP to a mature discipline are described, with special emphasis on the work of Phillips and Smagorinsky and their mentor Jule Charney.
Expedition 17 Automated Transfer Vehicle (ATV) Undocking
2008-09-05
ISS017-E-015468 (5 Sept. 2008) --- Backdropped by the blackness of space, European Space Agency's (ESA) "Jules Verne" Automated Transfer Vehicle (ATV) begins its relative separation from the International Space Station. The ATV undocked from the aft port of the Zvezda Service Module at 4:29 p.m. (CDT) on Sept. 5, 2008 and was placed in a parking orbit for three weeks, scheduled to be deorbited on Sept. 29 when lighting conditions are correct for an ESA imagery experiment of reentry.
Expedition 17 Automated Transfer Vehicle (ATV) Undocking
2008-09-05
ISS017-E-015496 (5 Sept. 2008) --- Backdropped by a blanket of clouds, European Space Agency's (ESA) "Jules Verne" Automated Transfer Vehicle (ATV) continues its relative separation from the International Space Station. The ATV undocked from the aft port of the Zvezda Service Module at 4:29 p.m. (CDT) on Sept. 5, 2008 and was placed in a parking orbit for three weeks, scheduled to be deorbited on Sept. 29 when lighting conditions are correct for an ESA imagery experiment of reentry.
Expedition 17 Automated Transfer Vehicle (ATV) Undocking
2008-09-05
ISS017-E-015451 (5 Sept. 2008) --- Backdropped by Earth's horizon and the blackness of space, European Space Agency's (ESA) "Jules Verne" Automated Transfer Vehicle (ATV) begins its relative separation from the International Space Station. The ATV undocked from the aft port of the Zvezda Service Module at 4:29 p.m. (CDT) on Sept. 5, 2008 and was placed in a parking orbit for three weeks, scheduled to be deorbited on Sept. 29 when lighting conditions are correct for an ESA imagery experiment of reentry.
Expedition 17 Automated Transfer Vehicle (ATV) Undocking
2008-09-05
ISS017-E-015446 (5 Sept. 2008) --- Backdropped by the blackness of space, European Space Agency's (ESA) "Jules Verne" Automated Transfer Vehicle (ATV) begins its relative separation from the International Space Station. The ATV undocked from the aft port of the Zvezda Service Module at 4:29 p.m. (CDT) on Sept. 5, 2008 and was placed in a parking orbit for three weeks, scheduled to be deorbited on Sept. 29 when lighting conditions are correct for an ESA imagery experiment of reentry.
Rubidium-strontium date of possibly 3 billion years for a granitic rock from antarctica.
Halpern, M
1970-09-04
A single total rock sample of biotite granite from Jule Peaks, Antarctica, has been dated by the rubidium-strontium method at about 3 billion years. The juxtaposition of this sector of Antarctica with Africa in the Dietz and Sproll continental drift reconstruction results in a possible geochronologic fit of the Princess Martha Coast of Antarctica with a covered possible notheastern extension of the African Swaziland Shield, which contains granitic rocks that are also 3 billion years old.
NASA Astrophysics Data System (ADS)
Ciampalini, Rossano; Kendon, Elizabeth; Constantine, José Antonio; Schindewolf, Marcus; Hall, Ian
2017-04-01
Climate change is expected to have a significant impact on the hydrological cycle, twenty-first century climate change simulations for Great Britain forecast an increase of surface runoff and flooding frequency. Once quality and resolution of the simulated rainfall deeply influence the results, we adopted rainfall simulations issued of a high-resolution climate model recently carried out for extended periods (13 years for present-day and future periods 2100) at 1.5 km grid scale over the south of the United Kingdom (simulations, which for the future period use the Intergovernmental Panel on Climate Change RCP 8.5 scenario, Kendon et al., 2014). We simulated soil erosion with 3D soil erosion model Schmidt (1990) on two catchments of Great Britain: the Rother catchment (350 km2) in West Sussex, England, because it has reported some of the most erosive events observed during the last 50 years in the UK, and the Conwy catchment (628 Km2) in North Wales, which is extremely resilient to soil erosion because of the abundant natural vegetation. Estimation of changes in soil moisture, saturation deficit as well as vegetation cover at daily time step have been done with the Joint UK Land Environment Simulator (JULES) (Best et al, 2011). Our results confirm the Rother catchment is the most erosive, while the Conwy catchment is the more resilient to soil erosion. Sediment production is perceived increase in both cases for the end of the century (27% and 50%, respectively). Seasonal disaggregation of the results revels that, while the most part of soil erosion is produced in winter months (DJF), the higher soil erosion variability for future periods is observed in summer (JJA). This behaviour is supported by the rainfall simulation analyse which highlighted this dual behaviour in precipitations.
Contribution of Jules Froment to the study of parkinsonian rigidity.
Broussolle, Emmanuel; Krack, Paul; Thobois, Stéphane; Xie-Brustolin, Jing; Pollak, Pierre; Goetz, Christopher G
2007-05-15
Rigidity is commonly defined as a resistance to passive movement. In Parkinson's disease (PD), two types of rigidity are classically recognized which may coexist, "leadpipe " and "cogwheel". Charcot was the first to investigate parkinsonian rigidity during the second half of the nineteenth century, whereas Negro and Moyer described cogwheel rigidity at the beginning of the twentieth century. Jules Froment, a French neurologist from Lyon, contributed to the study of parkinsonian rigidity during the 1920s. He investigated rigidity of the wrist at rest in a sitting position as well as in stable and unstable standing postures, both clinically and with physiological recordings using a myograph. With Gardère, Froment described enhanced resistance to passive movements of a limb about a joint that can be detected specifically when there is a voluntary action of another contralateral body part. This has been designated in the literature as the "Froment's maneuver " and the activation or facilitation test. In addition, Froment showed that parkinsonian rigidity diminishes, vanishes, or enhances depending on the static posture of the body. He proposed that in PD "maintenance stabilization " of the body is impaired and that "reactive stabilization " becomes the operative mode of muscular tone control. He considered "rigidification " as compensatory against the forces of gravity. Froment also demonstrated that parkinsonian rigidity increases during the Romberg test, gaze deviation, and oriented attention. In their number, breadth, and originality, Froment's contributions to the study of parkinsonian rigidity remain currently relevant to clinical and neurophysiological issues of PD. (c) 2007 Movement Disorder Society.
NASA Astrophysics Data System (ADS)
Zulkafli, Z. D.; Buytaert, W.; Veliz, C.
2014-12-01
The potential impact of a changing climate on Andean-Amazonian hydrology is an important question for scientists and policymakers alike, because of its implications for local ecosystem services such as water resources availability, river flow regulation, and eco-hydrology. This study presents new projections of climate change impacts on the hydrological regime of the upper Amazon river in Peru, and the consequent effect on two vulnerable species of freshwater turtle populations Podocnemis expansa (Amazon turtle) and Podocnemis unilis (yellow-spotted side neck turtle), which nest on its banks. To do this, the global climate model outputs of radiation, temperature, precipitation, wind, and humidity data from the Coupled Model Inter-comparison Project Phase 5 (CMIP5) are propagated through a hydrological model to simulate changes in river flow. The model consists of a land surface scheme called the Joint-UK Land Environment Simulator (JULES) that is coupled to a distributed river flow routing routine, which also accounts for floodplain attenuation of flood peaks. It is parameterized using a combination of remote sensing (TRMM, MODIS, an Landsat) and ground observational data to reproduce reliably the historical floodplain regime. The climate-induced shifts are inferred from a comparison between the RCP 4.5 and 8.5 projections against the historical scenario. Changes in the 10th and 95th percentile of flows, as well as the distributions in the length of the dry and wet seasons are analysed. These parameters are then used to construct probability models of biologically significant events (BSEs - extreme dry year, extreme wet year and repiquete), which are negative drivers of the turtle-egg ovipositioning, nesting and hatching. The results indicate that the projected increase in wet-season precipitation overcome the increase in evapotranspirative demand from an increase in temperature, resulting in more frequent and longer term flooding that causes a net loss of total turtle-egg counts. Additionally, changes in air and water temperature may alter the male / female ratio of the turtles.
The birth of numerical weather prediction
NASA Astrophysics Data System (ADS)
Wiin-Nielsen, A.
1991-08-01
The paper describes the major events leading gradually to operational, numerical, short-range predictions for the large-scale atmospheric flow. The theoretical foundation starting with Rossby's studies of the linearized, barotropic equation and ending a decade and a half later with the general formulation of the quasi-geostrophic, baroclinic model by Charney and Phillips is described. The problems connected with the very long waves and the inconsistences of the geostrophic approximation which were major obstacles in the first experimental forecasts are discussed. The resulting changes to divergent barotropic and baroclinic models and to the use of the balance equation are described. After the discussion of the theoretical foundation, the paper describes the major developments leading to the Meteorology Project at the Institute for Advanced Studied under the leadership of John von Neumann and Jule Charney followed by the establishment of the Joint Numerical Weather Prediction Unit in Suitland, Maryland. The interconnected developments in Europe, taking place more-or-less at the same time, are described by concentrating on the activities in Stockholm where the barotropic model was used in many experiments leading also to operational forecasts. The further developments resulting in the use of the primitive equations and the formulation of medium-range forecasting models are not included in the paper.
The birth of numerical weather prediction
NASA Astrophysics Data System (ADS)
Wiin-Nielsen, A.
1991-09-01
The paper describes the major events leading gradually to operational, numerical, short-range predictions for the large-scale atmospheric flow. The theoretical foundation starting with Rossby's studies of the linearized, barotropic equation and ending a decade and a half later with the general formulation of the quasi-geostrophic, baroclinic model by Charney and Phillips is described. The problems connected with the very long waves and the inconsistences of the geostrophic approximation which were major obstacles in the first experimental forecasts are discussed. The resulting changes to divergent barotropic and baroclinic models and to the use of the balance equation are described. After the discussion of the theoretical foundation, the paper describes the major developments leading to the Meteorology Project at the Institute for Advanced Studied under the leadership of John von Neumann and Jule Charney followed by the establishment of the Joint Numerical Weather Prediction Unit in Suitland, Maryland. The inter-connected developments in Europe, taking place more-or-less at the same time, are described by concentrating on the activities in Stockholm where the barotropic model was used in many experiments leading also to operational forecasts. The further developments resulting in the use of the primitive equations and the formulation of medium-range forecasting models are not included in the paper.
2014-09-10
CAPE CANAVERAL, Fla. – During a ceremony inside the Neil Armstrong Operations and Checkout Building high bay at NASA's Kennedy Space Center in Florida, the Orion spacecraft for Exploration Flight Test-1 was officially turned over to Lockheed Martin Ground Operations from Orion Assembly, Integration and Production. Holding the key during the turn over, are Jules Schneider, at left, Lockheed Martin Orion Production Operations manager, and Blake Hale, Lockheed Martin Ground Operations manager. Behind them are members of the Brevard Police and Fire Pipes and Drums. Orion is the exploration spacecraft designed to carry astronauts to destinations not yet explored by humans, including an asteroid and Mars. It will have emergency abort capability, sustain the crew during space travel and provide safe re-entry from deep space return velocities. The first unpiloted test flight of the Orion is scheduled to launch atop a United Launch Alliance Delta IV Heavy rocket from Cape Canaveral Air Force Station in Florida in December to an altitude of 3,600 miles above the Earth's surface. The two-orbit, four-hour flight test will help engineers evaluate the systems critical to crew safety including the heat shield, parachute system and launch abort system. For more information, visit http://www.nasa.gov/orion. Photo credit: NASA/Daniel Casper
2014-09-10
CAPE CANAVERAL, Fla. – During a ceremony inside the Neil Armstrong Operations and Checkout Building high bay at NASA's Kennedy Space Center in Florida, the Orion spacecraft for Exploration Flight Test-1 was officially turned over to Lockheed Martin Ground Operations from Orion Assembly, Integration and Production. Shaking hands during the turn over, are Jules Schneider, at left, Lockheed Martin Orion Production Operations manager, and Blake Hale, Lockheed Martin Ground Operations manager. Behind them are members of the Brevard Police and Fire Pipes and Drums. Orion is the exploration spacecraft designed to carry astronauts to destinations not yet explored by humans, including an asteroid and Mars. It will have emergency abort capability, sustain the crew during space travel and provide safe re-entry from deep space return velocities. The first unpiloted test flight of the Orion is scheduled to launch atop a United Launch Alliance Delta IV Heavy rocket from Cape Canaveral Air Force Station in Florida in December to an altitude of 3,600 miles above the Earth's surface. The two-orbit, four-hour flight test will help engineers evaluate the systems critical to crew safety including the heat shield, parachute system and launch abort system. For more information, visit http://www.nasa.gov/orion. Photo credit: NASA/Daniel Casper
2014-09-11
CAPE CANAVERAL, Fla. – Preparations are underway at the Neil Armstrong Operations and Checkout Building at NASA's Kennedy Space Center in Florida for the move of the Orion spacecraft for Exploration Flight Test-1 out of the high bay doors. Inside the high bay from left, are Jules Schneider, Lockheed Martin senior manager, and Kennedy Center Director Bob Cabana. The spacecraft will be transported to the Payload Hazardous Servicing Facility where it will be fueled ahead of its December flight test. Orion is the exploration spacecraft designed to carry astronauts to destinations not yet explored by humans, including an asteroid and Mars. It will have emergency abort capability, sustain the crew during space travel and provide safe re-entry from deep space return velocities. The first unpiloted test flight of the Orion is scheduled to launch atop a United Launch Alliance Delta IV Heavy rocket from Cape Canaveral Air Force Station in Florida to an altitude of 3,600 miles above the Earth's surface. The two-orbit, four-hour flight test will help engineers evaluate the systems critical to crew safety including the heat shield, parachute system and launch abort system. For more information, visit http://www.nasa.gov/orion. Photo credit: NASA/Daniel Casper
Intentions of Women (18-25 Years Old) to Join the Military: Results of a National Survey.
1978-09-01
MILITARY : RESULTS OF A NATIONAL SURVEY __________________________ S . PERFORMING ORG. N~PQRT NUMUER 7. Au fllON(.) S CONTRACT OR GRANT NUNSER(.) Jules...I. Borack S . PERFORMING ORGANI ZAtION N AME~~~~D ADDRE SS ~~~~. PRO GRAM ELEMENT. PROJECT. TaS~- AREA & WÔRK UNIT NUMSERS Navy Personnel Research and...non— Be interested in hiking. traditional women ’ s activities a- Marital status Be married . Be single. Financial Have financial responsibility Have no
National Service: A Responsibility, A Solution
1991-04-12
Il tws ~ 00" tic ethe audhoe pa~-~t c re a~ t (M i.W Of~’. NATOCNAL SERVICE: A RESPONSIBILITY , A’SOLUTION BY COLONE1L JULES W. h&’MP’ON United States...NUMBERS PROGRAM PROJECT I TASK WORK UNIT ELEMENT NO NO. NO. ACCESSION NO. 11. TITLE (Include Security Classification) NATIONAL SERVICE: A RESPONSIBILITY , A...0l DTIC USERS Unclassified 22a, NAME OF RESPONSIBLE INDIVIDUAL 22b TELEPHONE (Include Area Code) 122c OFFICE SYMBOL D n~D F r 1473. JU 8 PreSv:;, e
Lewis M. Rutherfurd and the First Photograph of Solar Granulation
NASA Astrophysics Data System (ADS)
Harvey, J. W.; Briggs, John W.; Prosser, Sian
2017-08-01
A major astronomical controversy of the mid-19th century was discordant descriptions of the small scale structure of the solar surface. Visual observers contradicted each other by describing the surface as consisting of “corrugations”, “willow leaves”, “rice grains”, “cumuli”, “thatch”, “granules”, etc. Early photographs of the solar surface were not good enough to settle the controversy. The French astronomer Jules Janssen is credited with the first 1876 photographs that clearly showed what we now call solar granulation (1876, CRAS 82, 1363). Upon seeing these images, New Yorker Lewis M. Rutherfurd (1878, MNRAS 38, 410) praised the high quality of Janssen’s images but asserted that he had also photographed granulation as early as 1871 using collodion wet plates. He sent copies of his best photograph to the Royal Astronomical Society to support his assertion. Curious about his claim, Briggs and Harvey set up Rutherfurd’s 13-inch achromatic refractor on Kitt Peak and found that it easily showed well-resolved solar granulation, so his claim might well have been justified. But without his plates we could not confirm the claim. For 140 years the copies of Rutherfurd’s best solar photograph remained in the archives of the Royal Astronomical Society and were recently discovered by Prosser (RAS Photographs A3/001B and A3/002). By coincidence a few days later, Briggs found the original August 11, 1871 plate. Despite poor condition these photographs show solar granulation. There are at least two other possible early claimants (Reade; Vogel) but their plates are almost certainly lost. Rutherfurd was a master of astronomical instrumentation and photography. He was reticent about his work, letting results speak for themselves, so it is satisfying to find that he was justified in making his claim of priority.
Pinto, Ana Catarina; Ferreira-Santos, Fernando; Lago, Lissandra Dal; de Azambuja, Evandro; Pimentel, Francisco Luís; Piccart-Gebhart, Martine; Razavi, Darius
2014-01-01
Background Information is vital to cancer patients. Physician–patient communication in oncology presents specific challenges. The aim of this study was to evaluate self-reported information of cancer patients in ambulatory care at a comprehensive cancer centre and examine its possible association with patients’ demographic and clinical characteristics. Patients and methods This study included adult patients with solid tumours undergoing chemotherapy at the Institute Jules Bordet’s Day Hospital over a ten-day period. EORTC QLQ-C30 and QLQ-INFO25 questionnaires were administered. Demographic and clinical data were collected. Descriptive and inferential statistics were used. Results 101 (99%) fully completed the questionnaires. They were mostly Belgian (74.3%), female (78.2%), with a mean age of 56.9 ± 12.8 years. The most frequent tumour was breast cancer (58.4%). Patients were well-informed about the disease and treatments, but presented unmet information domains. The Jules Bordet patients desired more information on treatment side effects, long-term outcome, nutrition, and recurrence symptoms. Patients on clinical trials reported having received less information about their disease and less written information than patients outside clinical trials. Higher information levels were associated with higher quality of life (QoL) scores and higher patient satisfaction. Conclusion Patients were satisfied with the information they received and this correlated with higher QoL, but they still expressed unmet information wishes. Additional studies are required to investigate the quality of the information received by patients enrolled in clinical trials. PMID:24834120
Jules Bernard Luys in Charcot's penumbra.
Parent, Martin; Parent, André
2011-01-01
Jules Bernard Luys (1828-1897) is a relatively unknown figure in 19th century French neuropsychiatry. Although greatly influenced by Jean-Martin Charcot (1825-1893), Luys worked in the shadow of the 'master of La Salpêtrière' for about a quarter of a century. When he arrived at this institution in 1862, he used microscopy and photomicrography to identify pathological lesions underlying locomotor ataxia and progressive muscular atrophy. He later made substantial contributions to our knowledge of normal human brain anatomy, including the elucidation of thalamic organization and the discovery of the subthalamic nucleus. Luys's name has long been attached to the latter structure (corps de Luys), which is at the center of our current thinking about the functional organization of basal ganglia and the physiopathology of Parkinson's disease. As head of the Maison de santé d'Ivry, Luys developed a highly original view of the functional organization of the normal human brain, while improving our understanding of the neuropathological and clinical aspects of mental illnesses. In 1886, Luys left La Salpêtrière and became chief physician at La Charité hospital. Following Charcot, whom he considered as the father of scientific hypnotism, Luys devoted the last part of his career to hysteria and hypnosis. However, Luys ventured too deeply into the minefield of hysteria. He initiated experiments as unconventional as the distant action of medication, and became one of the most highly caricatured examples of the fascination that hysteria exerted upon neurologists as well as laypersons at the end of the 19th century. Copyright © 2011 S. Karger AG, Basel.
Flooding from Intense Rainfall: an overview of project SINATRA
NASA Astrophysics Data System (ADS)
Cloke, Hannah
2014-05-01
Project SINATRA (Susceptibility of catchments to INTense RAinfall and flooding) is part of the UK NERC's Flooding From Intense Rainfall (FFIR) research programme which aims to reduce the risks of damage and loss of life caused by surface water and flash floods through improved identification, characterisation and prediction of interacting meteorological, hydrological and hydro-morphological processes that contribute to flooding associated with high-intensity rainfall events. Extreme rainfall events may only last for a few hours at most, but can generate terrifying and destructive floods. Their impact can be affected by a wide range factors (or processes) such as the location and intensity of the rainfall, the shape and steepness of the catchment it falls on, how much sediment is moved by the water and the vulnerability of the communities in the flood's path. Furthermore, FFIR are by their nature rapid, making it very difficult for researchers to 'capture' measurements during events. The complexity, speed and lack of field measurements on FFIR make it difficult to create computer models to predict flooding and often we are uncertain as to their accuracy. In addition there is no consensus on how to identify how particular catchments may be vulnerable to FFIR, due to factors such as catchment area, shape, geology and soil type as well as land-use. Additionally, the catchments most susceptible to FFIR are often small and un-gauged. Project SINATRA will: (1) Increase our understanding of what factors cause FFIR and gathering new, high resolution measurements of FFIR by: assembling an archive of past FFIR events in Britain and their impacts, as a prerequisite for improving our ability to predict future occurrences of FFIR; making real time observations of flooding during flood events as well as post-event surveys and historical event reconstruction, using fieldwork and crowd-sourcing methods; and characterizing the physical drivers for UK summer flooding events by identifying the large-scale atmospheric conditions associated with FFIR events, and linking them to catchment type. (2) Use this new understanding and data to improve models of FFIR so we can predict where they may happen nationwide by: employing an integrated catchment/urban scale modelling approach to FFIR at high spatial and temporal scales, modelling rapid catchment response to flash floods and their impacts in urban areas; scaling up to larger catchments by improving the representation of fast riverine and surface water flooding and hydromorphic change (including debris flow) in regional scale models of FFIR; improving the representation of FFIR in the JULES land surface model by integrating river routing and fast runoff processes, and performing assimilation of soil moisture and river discharge into the model run (3) Use these new findings and predictions to provide the Environment Agency and other professionals with information and software they can use to manage FFIR, reducing their damage and impact to communities by: developing tools to enable prediction of future FFIR impacts to support the Flood Forecasting Centre in issuing new 'impacts-based' warnings about their occurrence; developing a FFIR analysis tool to assess risks associated with rare events in complex situations involving incomplete knowledge, analogous to those developed for safety assessment in radioactive waste management.
[Delirium in delusions of negations of Cotard: syndrome versus disorder].
Huertas, D; Molina, J D; Chamorro, L; Toral, J
1997-01-01
This article constitutes the first of a series directed to review fundamental disorders in clinical psychogeriatrics. This sort of publication is intended to retrieve clinical practice as the cornerstone for research and teaching in psychiatry. Besides, and particularly in geriatry, we try to expand the strategy of liaison work with primary physicians. In this case, a nosological review of the so called "delusion of negations" is presented. The Jules Cotard's original concept of subtype of delusional melancholia is contrasted to the view of numerous authors in this century who have described it as a form of non-specific delusional syndrome.
ATV during Demonstration Day 1 Rendezvous Test
2008-03-29
ISS016-E-033720 (29 March 2008) --- Cosmonaut Yuri Malenchenko, Expedition 16 flight engineer, aboard the International Space Station used a digital still camera to record several images of the Jules Verne Automated Transfer Vehicle (ATV) during a rendezvous test March 29, 2008. Malenchenko fitted the camera with an 800mm lens typically employed for Shuttle RPM photography while the ATV sat 2.1 statute miles from the ISS during the first of two demonstration days in the lead up to a docking on April 3. On March 31, Demonstration Day 2 will see ATV approach to within 11 meters of the ISS.
2014-12-19
Lockheed Martin Manager Jules Schneider speaks to members of the media during a viewing of NASA's Orion spacecraft at the Launch Abort System Facility at NASA's Kennedy Space Center in Florida. The spacecraft's cross-country return, a 2,700 mile road trip from Naval Base San Diego to Kennedy, sets the stage for in-depth analysis of data obtained during Orion's trip to space. It will provide engineers detailed information on how the spacecraft fared during its two-orbit, 4.5-hour flight test, completed on Dec. 5. The Ground Systems Development and Operations Program led the recovery, offload and transportation efforts.
2014-12-19
Lockheed Martin Manager Jules Schneider speaks to members of the media during a viewing of NASA's Orion spacecraft at the Launch Abort System Facility at NASA's Kennedy Space Center in Florida. The spacecraft's cross-country return, a 2,700 mile road trip from Naval Base San Diego to Kennedy, sets the stage for in-depth analysis of data obtained during Orion's trip to space. It will provide engineers with detailed information on how the spacecraft fared during its two-orbit, 4.5-hour flight test, completed on Dec. 5. The Ground Systems Development and Operations Program led the recovery, offload and transportation efforts.
Raphaël Blanchard, parasitology, and the positioning of medical entomology in Paris.
Osborne, M A
2008-12-01
The histories of medical entomology and parasitology are entwined. Raphaël Blanchard (1857-1919), Chair of Medical Natural History and Parasitology at the Faculty of Medicine in Paris, organized the teaching of medical entomology and civilian colonial medicine. He also founded and edited the journal Archives de Parasitologie and started the Institute de Médecine Coloniale where he mentored many foreign students and researchers. Additionally, Blanchard is important for his scientific internationalism and medical historical work on the cultural location of parasitology and for training the future professors of parasitology Jules Guiart, Emile Brumpt, and Charles Joyeux.
NASA Astrophysics Data System (ADS)
Hamilton, D. S.; Carslaw, K. S.; Spracklen, D. V.; Folberth, G.; Kaplan, J. O.; Pringle, K.; Scott, C.
2015-12-01
Anthropogenic land use change (LUC) has had a major impact on the climate by altering the amount of carbon stored in vegetation, changing surface albedo and modifying the levels of both biogenic and pyrogenic emissions. While previous studies of LUC have largely focused on the first two components, there has recently been a recognition that changes to aerosol and related pre-cursor gas emissions from LUC are equally important. Furthermore, it has also recently been recognised that the pre-industrial (PI) to present day (PD) radiative forcing (RF) of climate from aerosol cloud interactions (ACI) due to anthropogenic emissions is highly sensitive to the amount of natural aerosol that was present in the PI. This suggests that anthropogenic RF from ACI may be highly sensitive to land-use in the PI. There are currently two commonly used baseline reference years for the PI; 1750 and 1860. Rapid LUC occurred between 1750 and 1860, with large reductions in natural vegetation cover in Eastern Northern America, Europe, Central Russia, India and Eastern China as well as lower reductions in parts of Brazil and Africa. This LUC will have led to significant changes in biogenic and fire emissions with implications for natural aerosol concentrations and PI-to-PD RF. The focus of this study is therefore to quantify the impact of LUC between 1750 and 1860 on aerosol concentrations and PI-to-PD RF calculations from ACI. We use the UK Met Office HadGEM3-UKCA coupled-chemistry-climate model to calculate the impacts of anthropogenic emissions and anthropogenic LUC on aerosol size distributions in both 1750 and 1860. We prescribe LUC using the KK10 historical dataset of land cover change. Monoterpene emissions are coupled directly to the prescribed LUC through the JULES land surface scheme in HadGEM3. Fire emissions from LUC were calculated offline using the fire module LPJ-LMfire in the Lund-Potsdam-Jena dynamic global vegetation model. To separate out the impacts of LUC from anthropogenic emissions a further simulation where only LUC and natural emissions are considered is undertaken. We then explore the sensitivity of PI-to-PD aerosol number concentrations, cloud drop number concentrations and the RF on assumed land-cover in the PI. This work will help determine the need for accurate descriptions of historical LUC in calculations of ACI.
Soil hydrophobicity - relating effects at atomic, molecular, core and national scales
NASA Astrophysics Data System (ADS)
Matthews, Peter; Doerr, Stefan; Van Keulen, Geertje; Dudley, Ed; Francis, Lewis; Whalley, Richard; Gazze, Andrea; Hallin, Ingrid; Quinn, Gerry; Sinclair, Kat; Ashton, Rhys
2016-04-01
The detrimental impacts of soil hydrophobicity include increased runoff, erosion and flooding, reduced biomass production, inefficient use of irrigation water and preferential leaching of pollutants. Its impacts may exacerbate flood risk associated with more extreme drought and precipitation events predicted with UK climate change scenarios. The UK's Natural Environment Research Council (NERC) has therefore funded a major research programme to investigate soil hydrophobicity over length scales ranging from atomic through molecular, core and landscape scale. This presentation gives an overview of the findings to date. The programme is predicated on the hypothesis that changes in soil protein abundance and localization, induced by variations in soil moisture and temperature, are crucial driving forces for transitions between hydrophobic and hydrophilic conditions at soil particle surfaces. Three soils were chosen based on the severity of hydrophobicity that can be achieved in the field: severe to extreme (Cefn Bryn, Gower, Wales), intermediate to severe (National Botanical Garden, Wales), and subcritical (Park Grass, Rothamsted Research near London). The latter is already highly characterised so was also used as a control. Hydrophobic/ hydrophilic transitions were measured from water droplet penetration times. Scientific advances in the following five areas will be described: (i) the identification of these soil proteins by proteomic methods, using a novel separation method which reduces interference by humic acids, and allows identification by ESI and MALDI TOF mass spectrometry and database searches, (ii) the examination of such proteins, which form ordered hydrophobic ridges, and measurement of their elasticity, stickiness and hydrophobicity at nano- to microscale using atomic force microscopy adapted for the rough surfaces of soil particles, (iii) the novel use of a picoliter goniometer to show hydrophobic effects at a 1 micron diameter droplet level, which avoids the averaging over soil cores and particles evident in microliter goniometry, with which the results are compared, (iv) measurements at core scale using water retention and wicking experiments, and (v) the interpretation, integration and upscaling of the results using a development of the PoreXpert void network model, a significant advance on the Van Genuchten approach. An explanation will also be given as to how the results will be incorporated into the JULES hydrological model of the UK Meteorological Office, used to predict flooding for different soil types and usage.
Implications of plant acclimation for future climate-carbon cycle feedbacks
NASA Astrophysics Data System (ADS)
Mercado, Lina; Kattge, Jens; Cox, Peter; Sitch, Stephen; Knorr, Wolfgang; Lloyd, Jon; Huntingford, Chris
2010-05-01
The response of land ecosystems to climate change and associated feedbacks are a key uncertainty in future climate prediction (Friedlingstein et al. 2006). However global models generally do not account for the acclimation of plant physiological processes to increased temperatures. Here we conduct a first global sensitivity study whereby we modify the Joint UK land Environment Simulator (JULES) to account for temperature acclimation of two main photosynthetic parameters, Vcmax and Jmax (Kattge and Knorr 2007) and plant respiration (Atkin and Tjoelker 2003). The model is then applied over the 21st Century within the IMOGEN framework (Huntingford et al. 2004). Model simulations will provide new and improved projections of biogeochemical cycling, forest resilience, and thus more accurate projections of climate-carbon cycle feedbacks and the future evolution of the Earth System. Friedlingstein P, Cox PM, Betts R et al. (2006) Climate-carbon cycle feedback analysis, results from the C4MIP model intercomparison. Journal of Climate, 19, 3337-3353. Kattge J and Knorr W (2007): Temperature acclimation in a biochemical model of photosynthesis: a reanalysis of data from 36 species. Plant, Cell and Environment 30, 1176-1190 Atkin O.K and Tjoelker, M. G. (2003): Thermal acclimation and the dynamic response of plant respiration to temperature. Trends in Plant Science 8 (7), 343-351 Huntingford C, et al. (2004) Using a GCM analogue model to investigate the potential for Amazonian forest dieback. Theoretical and Applied Climatology, 78, 177-185.
The ambiguity of drought events, a bottleneck for Amazon forest drought response modelling
NASA Astrophysics Data System (ADS)
De Deurwaerder, Hannes; Verbeeck, Hans; Baker, Timothy; Christoffersen, Bradley; Ciais, Philippe; Galbraith, David; Guimberteau, Matthieu; Kruijt, Bart; Langerwisch, Fanny; Meir, Patrick; Rammig, Anja; Thonicke, Kirsten; Von Randow, Celso; Zhang, Ke
2016-04-01
Considering the important role of the Amazon forest in the global water and carbon cycle, the prognosis of altered hydrological patterns resulting from climate change provides strong incentive for apprehending the direct implications of drought on the vegetation of this ecosystem. Dynamic global vegetation models have the potential of providing a useful tool to study drought impacts on various spatial and temporal scales. This however assumes the models being able to properly represent drought impact mechanisms. But how well do the models succeed in meeting this assumption? Within this study meteorological driver data and model output data of 4 different DGVMs, i.e. ORCHIDEE, JULES, INLAND and LPGmL, are studied. Using the palmer drought severity index (PDSI) and the mean cumulative water deficit (MWD), temporal and spatial representation of drought events are studied in the driver data and are referenced to historical extreme drought events in the Amazon. Subsequently, within the resulting temporal and spatial frame, we studied the drought impact on the above ground biomass (AGB) and gross primary production (GPP) fluxes. Flux tower data, field inventory data and the JUNG data-driven GPP product for the Amazon region are used for validation. Our findings not only suggest that the current state of the studied DGVMs is inadequate in representing Amazon droughts in general, but also highlights strong inter-model differences in drought responses. Using scatterplot-studies and input-output correlations, we provide insight in the origin of these encountered inter-model differences. In addition, we present directives of model development and improvement in scope of Amazon forest drought response modelling.
Improving rainfall representation for large-scale hydrological modelling of tropical mountain basins
NASA Astrophysics Data System (ADS)
Zulkafli, Zed; Buytaert, Wouter; Onof, Christian; Lavado, Waldo; Guyot, Jean-Loup
2013-04-01
Errors in the forcing data are sometimes overlooked in hydrological studies even when they could be the most important source of uncertainty. The latter particularly holds true in tropical countries with short historical records of rainfall monitoring and remote areas with sparse rain gauge network. In such instances, alternative data such as the remotely sensed precipitation from the TRMM (Tropical Rainfall Measuring Mission) satellite have been used. These provide a good spatial representation of rainfall processes but have been established in the literature to contain volumetric biases that may impair the results of hydrological modelling or worse, are compensated during model calibration. In this study, we analysed precipitation time series from the TMPA (TRMM Multiple Precipitation Algorithm, version 6) against measurements from over 300 gauges in the Andes and Amazon regions of Peru and Ecuador. We found moderately good monthly correlation between the pixel and gauge pairs but a severe underestimation of rainfall amounts and wet days. The discrepancy between the time series pairs is particularly visible over the east side of the Andes and may be attributed to localized and orographic-driven high intensity rainfall, which the satellite product may have limited skills at capturing due to technical and scale issues. This consequently results in a low bias in the simulated streamflow volumes further downstream. In comparison, with the recently released TMPA, version 7, the biases reduce. This work further explores several approaches to merge the two sources of rainfall measurements, each of a different spatial and temporal support, with the objective of improving the representation of rainfall in hydrological simulations. The methods used are (1) mean bias correction (2) data assimilation using Kalman filter Bayesian updating. The results are evaluated by means of (1) a comparison of runoff ratios (the ratio of the total runoff and the total precipitation over an extended period) in multiple basins, and (2) a comparison of the outcome of hydrological modelling using the distributed JULES (Joint-UK Land Environment Simulator) land surface model. First results indicate an improvement in the water balance that directly translates into an increased hydrological performance. The more interesting aspect of the study, however, will be the insights into the nature of satellite precipitation errors in this extreme environment and the optimal means of improving the data to generate increased confidence in hydrological predictions.
When the Patient Believes That the Organs Are Destroyed: Manifestation of Cotard's Syndrome.
Machado, Leonardo; Filho, Luiz Evandro de Lima; Machado, Liliane
2016-01-01
Cotard's Syndrome (CS) is a rare clinical event described for the first time in 1880 by the neurologist and psychiatrist Jules Cotard and characterized by negation delusions (or nihilists). Immortality and hypochondriac delusions are also typical. Nowadays, it is known that CS can be associated with many neuropsychiatric conditions. In this article, we describe the case of a patient that believed not having more organs and having the body deformed and whose CS was associated with a bigger depressive disorder. Although the electroconvulsive therapy is the most described treatment modality in the literature, the reported case had therapeutic success with association of imipramine and risperidone.
Numerical analysis and modeling of atmospheric phenomena
NASA Technical Reports Server (NTRS)
Stone, Peter H.
1994-01-01
For the past 22 years Grant NGR 22-009-727 has been supporting research in the Center for Meteorology and Physical Oceanography (and its predecessors) in a wide variety of diagnostic and modeling studies of atmospheric and ocean phenomena. Professor Jule Charney was the initial Principal Investigator. Professor Peter Stone joined him as co-Principal Investigator in 1975 and became the sole Principal Investigator in 1981. During its lifetime the Grant has supported in whole or in part 11 Master's theses, 14 Ph.D. theses, and 45 papers published in refereed scientific journals. All of these theses and papers (with bibliographic references) are listed below. All but one of the theses were used to fulfill the requirements for MIT (Massachusetts Institute of Technology) degrees and are available from the MIT libraries. The one exception is F. Chen's Ph.D. thesis which was for a Harvard degree and is available from the Harvard libraries. In addition to the work described in the citations listed below, the Grant has supported Research Assistant Amy Solomon during the past two years to carry out a study of how baroclinic adjustment is affected by vertical resolution, vertical temperature structure, and dissipation. Ms. Solomon plans to use this project for her Ph.D. thesis. Support for this project will continue under NASA Grant NAG 5-2490, 'The Factors Controlling Poleward Heat Transport in Climate Models.'
Carbon dioxide and climate: a second assessment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
For over a century, concern has been expressed that increases in atmospheric carbon dioxide (CO/sub 2/) concentration could affect global climate by changing the heat balance of the atmosphere and Earth. Observations reveal steadily increasing concentrations of CO/sub 2/, and experiments with numerical climate models indicate that continued increase would eventually produce significant climatic change. Comprehensive assessment of the issue will require projection of future CO/sub 2/ emissions and study of the disposition of this excess carbon in the atmosphere, ocean, and biota; the effect on climate; and the implications for human welfare. This study focuses on one aspect, estimationmore » of the effect on climate of assumed future increases in atmospheric CO/sub 2/. Conclusions are drawn principally from present-day numerical models of the climate system. To address the significant role of the oceans, the study also makes use of observations of the distributions of anthropogenic tracers other than CO/sub 2/. The rapid scientific developments in these areas suggest that periodic reassessments will be warranted. The starting point for the study was a similar 1979 review by a Climate Research Board panel chaired by the late Jule G. Charney. The present study has not found any new results that necessitate substantial revision of the conclusions of the Charney report.« less
NASA Astrophysics Data System (ADS)
Carvalhais, N.; Thurner, M.; Beer, C.; Forkel, M.; Rademacher, T. T.; Santoro, M.; Tum, M.; Schmullius, C.
2015-12-01
While vegetation productivity is known to be strongly correlated to climate, there is a need for an improved understanding of the underlying processes of vegetation carbon turnover and their importance at a global scale. This shortcoming has been due to the lack of spatially extensive information on vegetation carbon stocks, which we recently have been able to overcome by a biomass dataset covering northern boreal and temperate forests originating from radar remote sensing. Based on state-of-the-art products on biomass and NPP, we are for the first time able to study the relation between carbon turnover rate and a set of climate indices in northern boreal and temperate forests. The implementation of climate-related mortality processes, for instance drought, fire, frost or insect effects, is often lacking or insufficient in current global vegetation models. In contrast to our observation-based findings, investigated models from the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP), including HYBRID4, JeDi, JULES, LPJml, ORCHIDEE, SDGVM, and VISIT, are able to reproduce spatial climate - turnover rate relationships only to a limited extent. While most of the models compare relatively well to observation-based NPP, simulated vegetation carbon stocks are severely biased compared to our biomass dataset. Current limitations lead to considerable uncertainties in the estimated vegetation carbon turnover, contributing substantially to the forest feedback to climate change. Our results are the basis for improving mortality concepts in global vegetation models and estimating their impact on the land carbon balance.
NASA Astrophysics Data System (ADS)
Hoar, T. J.; Anderson, J. L.; Collins, N.; Kershaw, H.; Hendricks, J.; Raeder, K.; Mizzi, A. P.; Barré, J.; Gaubert, B.; Madaus, L. E.; Aydogdu, A.; Raeder, J.; Arango, H.; Moore, A. M.; Edwards, C. A.; Curchitser, E. N.; Escudier, R.; Dussin, R.; Bitz, C. M.; Zhang, Y. F.; Shrestha, P.; Rosolem, R.; Rahman, M.
2016-12-01
Strongly-coupled ensemble data assimilation with multiple high-resolution model components requires massive state vectors which need to be efficiently stored and accessed throughout the assimilation process. Supercomputer architectures are tending towards increasing the number of cores per node but have the same or less memory per node. Recent advances in the Data Assimilation Research Testbed (DART), a freely-available community ensemble data assimilation facility that works with dozens of large geophysical models, have addressed the need to run with a smaller memory footprint on a higher node count by utilizing MPI-2 one-sided communication to do non-blocking asynchronous access of distributed data. DART runs efficiently on many computational platforms ranging from laptops through thousands of cores on the newest supercomputers. Benefits of the new DART implementation will be shown. In addition, overviews of the most recently supported models will be presented: CAM-CHEM, WRF-CHEM, CM1, OpenGGCM, FESOM, ROMS, CICE5, TerrSysMP (COSMO, CLM, ParFlow), JULES, and CABLE. DART provides a comprehensive suite of software, documentation, and tutorials that can be used for ensemble data assimilation research, operations, and education. Scientists and software engineers at NCAR are available to support DART users who want to use existing DART products or develop their own applications. Current DART users range from university professors teaching data assimilation, to individual graduate students working with simple models, through national laboratories and state agencies doing operational prediction with large state-of-the-art models.
Evaluating the UK's carbon budget using a dense network of tall-tower observations
NASA Astrophysics Data System (ADS)
White, E.; Rigby, M. L.; Manning, A.; Lunt, M. F.; Ganesan, A.; O'Doherty, S.; Stavert, A.; Stanley, K. M.; Williams, M. D.; Smallman, T. L.; Comyn-Platt, E.; Levy, P. E.
2017-12-01
The UK has committed to reducing greenhouse gas (GHG) emissions to 80% of 1990 levels by 2050. Evaluating the UK's GHG emissions, and in particular those of carbon dioxide, is imperative to the UK's ability to track progress towards these goals. Making top-down estimates of regional carbon dioxide emissions is challenging due to the rapid temporal variability in the biogenic flux, and the co-location of anthropogenic and biogenic sources and sinks. We present a hierarchical Bayesian inverse modelling framework, which is able to estimate a yearly total (anthropogenic and biogenic) carbon dioxide budget for the UK. Using observations from a high-density GHG monitoring network, combined with high temporal resolution prior information and a Lagrangian atmospheric transport model (NAME, developed by the UK Met Office), we derive a net positive flux for the UK of 0.39 Pg/yr in 2014. We will compare the outcome of inversions that used prior information from two different biosphere models, CARDAMOM and JULES. This comparison helps to understand more about the biogenic processes contributing to the UK's carbon dioxide budget, limitations with different modelling approaches and the sensitivity of the inversion framework to the choice of prior. A better understanding of how the biogenic flux changes throughout the year can, in turn, help to improve the UK's anthropogenic carbon dioxide inventory by identifying times in the year when the anthropogenic signal may be possible to detect.
NASA Astrophysics Data System (ADS)
Anonymous
2012-10-01
Many AGU members are among the American Meteorological Society's (AMS) 2013 honorary members, awardees, lecturers, and fellows. Among the AMS honorary members is Susan Solomon, the Ellen Swallow Richards Professor of Atmospheric Chemistry and Climate Science at the Massachusetts Institute of Technology (MIT). Dennis Hartmann, of the University of Washington, Seattle, is the recipient of AMS's Carl-Gustaf Rossby Research Medal "for significant contributions to the synthesis of knowledge of radiative and dynamical processes leading to a deeper understanding of the climate system." R. Alan Plumb, professor of meteorology at MIT, receives the Jule G. Charney Award "for fundamental contributions to the understanding of geophysical fluid dynamics, stratospheric dynamics, chemical transport, and the general circulation of the atmosphere and oceans." The Verner E. Suomi Award has been given to Richard Johnson, professor of atmospheric science at Colorado State University, Fort Collins, "for exquisite design of rawinsonde networks in field campaigns and insightful analysis of interactions between convective clouds and the largescale atmospheric circulation." W. Kendall Melville, professor of oceanography at the Scripps Institution of Oceanography, University of California, San Diego, has been awarded the Sverdrup Gold Medal Award "for pioneering contributions in advancing knowledge on the role of surface wave breaking and related processes in air-sea interaction." AMS announced that Laurence Armi, also a professor of oceanography at Scripps, is recipient of the Henry Stommel Research Award "for his deeply insightful studies of stratified flow, his pioneering work on boundary mixing and other turbulent mechanisms."
When the Patient Believes That the Organs Are Destroyed: Manifestation of Cotard's Syndrome
Machado, Liliane
2016-01-01
Cotard's Syndrome (CS) is a rare clinical event described for the first time in 1880 by the neurologist and psychiatrist Jules Cotard and characterized by negation delusions (or nihilists). Immortality and hypochondriac delusions are also typical. Nowadays, it is known that CS can be associated with many neuropsychiatric conditions. In this article, we describe the case of a patient that believed not having more organs and having the body deformed and whose CS was associated with a bigger depressive disorder. Although the electroconvulsive therapy is the most described treatment modality in the literature, the reported case had therapeutic success with association of imipramine and risperidone. PMID:28003827
2014-12-19
CAPE CANAVERAL, Fla. -- Lockheed Martin Manager Jules Schneider speaks to members of the media during a viewing of NASA's Orion spacecraft at the Launch Abort System Facility at NASA's Kennedy Space Center in Florida. The spacecraft's cross-country return, a 2,700 mile road trip from Naval Base San Diego to Kennedy, sets the stage for in-depth analysis of data obtained during Orion's trip to space. It will provide engineers with detailed information on how the spacecraft fared during its two-orbit, 4.5-hour flight test, completed on Dec. 5. The Ground Systems Development and Operations Program led the recovery, offload and transportation efforts. For more information, visit www.nasa.gov/orion. Photo credit: NASA/Dimitri Gerondidakis
2004-04-15
Science fiction writers, like Jules Verne in France and Edward Everett Hale in America, had discovered one of the most vital elements in the formula for space travel-a fertile imagination. The first known proposal for a marned-satellite appears in a story by Hale entitled "The Brick Moon" published in 1899. The story involved a group of young Bostonians who planned to put an artificial satellite into polar orbit for sailors to use to determine longitude accurately and easily. They planned to send a brick satellite into orbit because the satellite would have to withstand fire very well. The Satellite's 37 inhabitants signaled the Earth in morse code by jumping up and down on the outside of the satellite.
2014-12-19
NASA's Orion spacecraft is viewed by members of the media at the Launch Abort System Facility at NASA's Kennedy Space Center in Florida. Speaking to the media during the viewing opportunity is Jules Schneider, Lockheed Martin Manager. Behind him, from left, are Glenn Chin, Orion Production Operations manager and Phil Weber and Lou Garcia, with the Ground Systems Development and Operations Program, or GSDO. Orion made the 8-day, 2,700 mile overland trip back to Kennedy from Naval Base San Diego in California. Analysis of date obtained during its two-orbit, four-and-a-half hour mission Dec. 5 will provide engineers with detailed information on how the spacecraft fared. GSDO led the recovery, offload and transportation efforts.
Development of noise emission measurement specifications for color printing multifunctional devices
NASA Astrophysics Data System (ADS)
Kimizuka, Ikuo
2005-09-01
Color printing (including copying) is becoming more popular application in home, as well as in offices. Existing de jule and/or industrial standards (such as ISO 7779, ECMA-74, ANSI S12.10 series, etc.), however, state only monochrome patterns, which are mainly intended for acoustic noise testing of mechanical impact type printers. This paper discusses the key issues and corresponding resolutions for development of color printing patterns for acoustic noise measurements. The results of these technical works will be published by JBMS-74 (new industry standard of JBMIA within 2005), and hopefully be the technical basis of updating other standards mentioned above. This paper also shows the development processes and key features of proposed patterns.
2014-12-19
CAPE CANAVERAL, Fla. -- Lockheed Martin Manager Jules Schneider speaks to members of the media during a viewing of NASA's Orion spacecraft at the Launch Abort System Facility at NASA's Kennedy Space Center in Florida. The spacecraft's cross-country return, a 2,700 mile road trip from Naval Base San Diego to Kennedy, sets the stage for in-depth analysis of data obtained during Orion's trip to space. It will provide engineers with detailed information on how the spacecraft fared during its two-orbit, 4.5-hour flight test, completed on Dec. 5. The Ground Systems Development and Operations Program led the recovery, offload and transportation efforts. For more information, visit www.nasa.gov/orion. Photo credit: NASA/Dimitri Gerondidakis
2014-12-19
NASA's Orion spacecraft is viewed by members of the media at the Launch Abort System Facility at NASA's Kennedy Space Center in Florida. Speaking to the media during the viewing opportunity is Phil Weber, with the Ground Systems Development and Operations Program, or GSDO. At left is Jules Schneider, Lockheed Martin manager. At right is Glenn Chin, Orion Production Operations, and Lou Garcia, with GSDO. Orion made the 8-day, 2,700 mile overland trip back to Kennedy from Naval Base San Diego in California. Analysis of date obtained during its two-orbit, four-and-a-half hour mission Dec. 5 will provide engineers detailed information on how the spacecraft fared. GSDO led the recovery, offload and transportation efforts.
2014-12-19
CAPE CANAVERAL, Fla. -- Lockheed Martin Manager Jules Schneider speaks to members of the media during a viewing of NASA's Orion spacecraft at the Launch Abort System Facility at NASA's Kennedy Space Center in Florida. The spacecraft's cross-country return, a 2,700 mile road trip from Naval Base San Diego to Kennedy, sets the stage for in-depth analysis of data obtained during Orion's trip to space. It will provide engineers with detailed information on how the spacecraft fared during its two-orbit, 4.5-hour flight test, completed on Dec. 5. The Ground Systems Development and Operations Program led the recovery, offload and transportation efforts. For more information, visit www.nasa.gov/orion. Photo credit: NASA/Dimitri Gerondidakis
NASA Technical Reports Server (NTRS)
2004-01-01
Science fiction writers, like Jules Verne in France and Edward Everett Hale in America, had discovered one of the most vital elements in the formula for space travel-a fertile imagination. The first known proposal for a marned-satellite appears in a story by Hale entitled 'The Brick Moon' published in 1899. The story involved a group of young Bostonians who planned to put an artificial satellite into polar orbit for sailors to use to determine longitude accurately and easily. They planned to send a brick satellite into orbit because the satellite would have to withstand fire very well. The Satellite's 37 inhabitants signaled the Earth in morse code by jumping up and down on the outside of the satellite.
The body's tailored suit: Skin as a mechanical interface.
Tissot, Floriane S; Boulter, Etienne; Estrach, Soline; Féral, Chloé C
2016-11-01
Skin, by nature, is very similar to the Rouquayrol-Denayrouze suit mentioned by Jules Verne in Twenty Thousand Leagues Under the Sea: it allows "to risk (…) new physiological conditions without suffering any organic disorder". Mechanical cues, to the same extent as other environmental parameters, are such "new physiological conditions". Indeed, skin's primary function is to form a protective barrier to shield inner tissues from the external environment. This requires unique mechanical properties as well as the ability to sense mechanical cues from the environment in order to prevent or repair mechanical damages as well as to function as the primary mechanosensory interface of the whole body. Copyright © 2016 Elsevier GmbH. All rights reserved.
NASA Astrophysics Data System (ADS)
Matthews, G. Peter; Doerr, Stefan; Van Keulen, Geertje; Dudley, Ed; Francis, Lewis; Whalley, Richard; Gazze, Andrea; Hallin, Ingrid; Quinn, Gerry; Sinclair, Kat; Ashton, Rhys
2017-04-01
Soil hydrophobicity can lead to reduced soil fertility and heightened flood risk caused by increased run-off. Soil hydrophobicity is a well-known phenomenon when induced by natural events such as wildfires and anthropogenic causes including adding organic wastes or hydrocarbon contaminants. This presentation concerns a much more subtle effect - the naturally occurring changes between hydrophilic and hydrophobic states caused by periods of wetness and drought. Although subtle, they nevertheless affect vast areas of soil, and so their effects can be very significant, and are predicted to increase under climate change conditions. To understand the effect, a major interdisciplinary study has been commissioned by the UK's Natural Environment Research Council (NERC) to investigate soil hydrophobicity over length scales ranging from atomic through molecular, core and landscape scale. We present the key findings from the many publications currently in preparation. The programme is predicated on the hypothesis that changes in soil protein abundance and localization, induced by variations in soil moisture and temperature, are crucial driving forces for transitions between hydrophobic and hydrophilic conditions at soil particle surfaces, and that these effects can be meaningfully upscaled from molecular to landscape scale. Three soils were chosen based on the severity of hydrophobicity that can be achieved in the field: severe to extreme (natural rough pasture, Wales), intermediate to severe (pasture, Wales), and subcritical (managed research grassland, Rothamsted Research, England). The latter is already highly characterised so was also used as a control. Hydrophobic/ hydrophilic transitions were determined from water droplet penetration times. Scientific advances in the following five areas will be described: (i) the identification of these soil proteins by proteomic methods, using novel separation methods which reduces interference by humic acids, and allows identification by ESI and MALDI TOF mass spectrometry and database searches, (ii) the examination of such proteins, which form ordered hydrophobic ridges, and measurement of their elasticity, stickiness and hydrophobicity at nano- to microscale using atomic force microscopy adapted for the rough surfaces of soil particles, (iii) the novel use of a picoliter goniometer to show hydrophobic effects at a 1 micron diameter droplet level, which avoids the averaging over soil cores and particles evident in microliter goniometry, with which the results are compared, (iv) measurements at core scale using water retention and wicking experiments, and (v) the modelling and upscaling of the results from molecular to core scale using the PoreXpert void network model of dynamic wetting and Haines jumps. An explanation will also be given as to how the results will be further upscaled by incorporation into the JULES hydrological model of the UK Meteorological Office, used to predict flooding for different soil types and usage.
A multi-model assessment of terrestrial biosphere model data needs
NASA Astrophysics Data System (ADS)
Gardella, A.; Cowdery, E.; De Kauwe, M. G.; Desai, A. R.; Duveneck, M.; Fer, I.; Fisher, R.; Knox, R. G.; Kooper, R.; LeBauer, D.; McCabe, T.; Minunno, F.; Raiho, A.; Serbin, S.; Shiklomanov, A. N.; Thomas, A.; Walker, A.; Dietze, M.
2017-12-01
Terrestrial biosphere models provide us with the means to simulate the impacts of climate change and their uncertainties. Going beyond direct observation and experimentation, models synthesize our current understanding of ecosystem processes and can give us insight on data needed to constrain model parameters. In previous work, we leveraged the Predictive Ecosystem Analyzer (PEcAn) to assess the contribution of different parameters to the uncertainty of the Ecosystem Demography model v2 (ED) model outputs across various North American biomes (Dietze et al., JGR-G, 2014). While this analysis identified key research priorities, the extent to which these priorities were model- and/or biome-specific was unclear. Furthermore, because the analysis only studied one model, we were unable to comment on the effect of variability in model structure to overall predictive uncertainty. Here, we expand this analysis to all biomes globally and a wide sample of models that vary in complexity: BioCro, CABLE, CLM, DALEC, ED2, FATES, G'DAY, JULES, LANDIS, LINKAGES, LPJ-GUESS, MAESPA, PRELES, SDGVM, SIPNET, and TEM. Prior to performing uncertainty analyses, model parameter uncertainties were assessed by assimilating all available trait data from the combination of the BETYdb and TRY trait databases, using an updated multivariate version of PEcAn's Hierarchical Bayesian meta-analysis. Next, sensitivity analyses were performed for all models across a range of sites globally to assess sensitivities for a range of different outputs (GPP, ET, SH, Ra, NPP, Rh, NEE, LAI) at multiple time scales from the sub-annual to the decadal. Finally, parameter uncertainties and model sensitivities were combined to evaluate the fractional contribution of each parameter to the predictive uncertainty for a specific variable at a specific site and timescale. Facilitated by PEcAn's automated workflows, this analysis represents the broadest assessment of the sensitivities and uncertainties in terrestrial models to date, and provides a comprehensive roadmap for constraining model uncertainties through model development and data collection.
NASA Astrophysics Data System (ADS)
Rowland, L.; Harper, A.; Christoffersen, B. O.; Galbraith, D. R.; Imbuzeiro, H. M. A.; Powell, T. L.; Doughty, C.; Levine, N. M.; Malhi, Y.; Saleska, S. R.; Moorcroft, P. R.; Meir, P.; Williams, M.
2014-11-01
Accurately predicting the response of Amazonia to climate change is important for predicting changes across the globe. However, changes in multiple climatic factors simultaneously may result in complex non-linear responses, which are difficult to predict using vegetation models. Using leaf and canopy scale observations, this study evaluated the capability of five vegetation models (CLM3.5, ED2, JULES, SiB3, and SPA) to simulate the responses of canopy and leaf scale productivity to changes in temperature and drought in an Amazonian forest. The models did not agree as to whether gross primary productivity (GPP) was more sensitive to changes in temperature or precipitation. There was greater model-data consistency in the response of net ecosystem exchange to changes in temperature, than in the response to temperature of leaf area index (LAI), net photosynthesis (An) and stomatal conductance (gs). Modelled canopy scale fluxes are calculated by scaling leaf scale fluxes to LAI, and therefore in this study similarities in modelled ecosystem scale responses to drought and temperature were the result of inconsistent leaf scale and LAI responses among models. Across the models, the response of An to temperature was more closely linked to stomatal behaviour than biochemical processes. Consequently all the models predicted that GPP would be higher if tropical forests were 5 °C colder, closer to the model optima for gs. There was however no model consistency in the response of the An-gs relationship when temperature changes and drought were introduced simultaneously. The inconsistencies in the An-gs relationships amongst models were caused by to non-linear model responses induced by simultaneous drought and temperature change. To improve the reliability of simulations of the response of Amazonian rainforest to climate change the mechanistic underpinnings of vegetation models need more complete validation to improve accuracy and consistency in the scaling of processes from leaf to canopy.
Simulated permafrost soil thermal dynamics during 1960-2009 in eight offline processed-based models
NASA Astrophysics Data System (ADS)
Peng, S.; Gouttevin, I.; Krinner, G.; Ciais, P.
2013-12-01
Permafrost soil thermal dynamics not only determine the status of permafrost, but also have large impacts on permafrost organic carbon decomposition. Here, we used eight processed based models that participated in the Vulnerability Permafrost Carbon Research Coordination Network (RCN) project to investigate: (1) the trends in soil temperature at different depths over the northern hemisphere permafrost region during the past five decades, and (2) which factors drive trends and inter-annual variability of permafrost soil temperature? The simulated annual soil temperature at 20cm increases by ~0.02 °C per year from 1960 to 2009 (ranging from 0.00 °C per year in CoLM to 0.04 °C per year in ISBA). Most models simulated more warming of soil in spring and winter than in summer and autumn, although there were different seasonal trends in different models. Trends in soil temperature decrease with soil depth in all models. To quantify the contributions of various factors (air temperature, precipitation, downward longwave radiation etc.) to trends and inter-annual variation in soil temperature, we ran offline models with detrended air temperature, precipitation, downward longwave radiation, respectively. Our results suggest that both annual air temperature and downward longwave radiation significantly correlate with annual soil temperature. Moreover, trend in air temperature and downward longwave radiation contribute 30% and 60% to trends in soil temperature (0 - 200cm), respectively, during the period 1960-2009. Spatial distributions of trend in annual soil temperature at 20cm from R01 simulations of (a) CLM4, (b) CoLM, (c) ISBA, (d) JULES, (e) LPJ_GUESS, (f) ORCHIDEE, (g) UVic and (h) UW-VIC during the period 1960-2009.
NASA Technical Reports Server (NTRS)
Farnham, Steven J., II; Garza, Joel, Jr.; Castillo, Theresa M.; Lutomski, Michael
2011-01-01
In 2007 NASA was preparing to send two new visiting vehicles carrying logistics and propellant to the International Space Station (ISS). These new vehicles were the European Space Agency s (ESA) Automated Transfer Vehicle (ATV), the Jules Verne, and the Japanese Aerospace and Explorations Agency s (JAXA) H-II Transfer Vehicle (HTV). The ISS Program wanted to quantify the increased risk to the ISS from these visiting vehicles. At the time, only the Shuttle, the Soyuz, and the Progress vehicles rendezvoused and docked to the ISS. The increased risk to the ISS was from an increase in vehicle traffic, thereby, increasing the potential catastrophic collision during the rendezvous and the docking or berthing of the spacecraft to the ISS. A universal method of evaluating the risk of rendezvous and docking or berthing was created by the ISS s Risk Team to accommodate the increasing number of rendezvous and docking or berthing operations due to the increasing number of different spacecraft, as well as the future arrival of commercial spacecraft. Before the first docking attempt of ESA's ATV and JAXA's HTV to the ISS, a probabilistic risk model was developed to quantitatively calculate the risk of collision of each spacecraft with the ISS. The 5 rendezvous and docking risk models (Soyuz, Progress, Shuttle, ATV, and HTV) have been used to build and refine the modeling methodology for rendezvous and docking of spacecrafts. This risk modeling methodology will be NASA s basis for evaluating the addition of future ISS visiting spacecrafts hazards, including SpaceX s Dragon, Orbital Science s Cygnus, and NASA s own Orion spacecraft. This paper will describe the methodology used for developing a visiting vehicle risk model.
NASA Astrophysics Data System (ADS)
Chadburn, Sarah E.; Krinner, Gerhard; Porada, Philipp; Bartsch, Annett; Beer, Christian; Belelli Marchesini, Luca; Boike, Julia; Ekici, Altug; Elberling, Bo; Friborg, Thomas; Hugelius, Gustaf; Johansson, Margareta; Kuhry, Peter; Kutzbach, Lars; Langer, Moritz; Lund, Magnus; Parmentier, Frans-Jan W.; Peng, Shushi; Van Huissteden, Ko; Wang, Tao; Westermann, Sebastian; Zhu, Dan; Burke, Eleanor J.
2017-11-01
It is important that climate models can accurately simulate the terrestrial carbon cycle in the Arctic due to the large and potentially labile carbon stocks found in permafrost-affected environments, which can lead to a positive climate feedback, along with the possibility of future carbon sinks from northward expansion of vegetation under climate warming. Here we evaluate the simulation of tundra carbon stocks and fluxes in three land surface schemes that each form part of major Earth system models (JSBACH, Germany; JULES, UK; ORCHIDEE, France). We use a site-level approach in which comprehensive, high-frequency datasets allow us to disentangle the importance of different processes. The models have improved physical permafrost processes and there is a reasonable correspondence between the simulated and measured physical variables, including soil temperature, soil moisture and snow. We show that if the models simulate the correct leaf area index (LAI), the standard C3 photosynthesis schemes produce the correct order of magnitude of carbon fluxes. Therefore, simulating the correct LAI is one of the first priorities. LAI depends quite strongly on climatic variables alone, as we see by the fact that the dynamic vegetation model can simulate most of the differences in LAI between sites, based almost entirely on climate inputs. However, we also identify an influence from nutrient limitation as the LAI becomes too large at some of the more nutrient-limited sites. We conclude that including moss as well as vascular plants is of primary importance to the carbon budget, as moss contributes a large fraction to the seasonal CO2 flux in nutrient-limited conditions. Moss photosynthetic activity can be strongly influenced by the moisture content of moss, and the carbon uptake can be significantly different from vascular plants with a similar LAI. The soil carbon stocks depend strongly on the rate of input of carbon from the vegetation to the soil, and our analysis suggests that an improved simulation of photosynthesis would also lead to an improved simulation of soil carbon stocks. However, the stocks are also influenced by soil carbon burial (e.g. through cryoturbation) and the rate of heterotrophic respiration, which depends on the soil physical state. More detailed below-ground measurements are needed to fully evaluate biological and physical soil processes. Furthermore, even if these processes are well modelled, the soil carbon profiles cannot resemble peat layers as peat accumulation processes are not represented in the models. Thus, we identify three priority areas for model development: (1) dynamic vegetation including (a) climate and (b) nutrient limitation effects; (2) adding moss as a plant functional type; and an (3) improved vertical profile of soil carbon including peat processes.
Beyond equilibrium climate sensitivity
NASA Astrophysics Data System (ADS)
Knutti, Reto; Rugenstein, Maria A. A.; Hegerl, Gabriele C.
2017-10-01
Equilibrium climate sensitivity characterizes the Earth's long-term global temperature response to increased atmospheric CO2 concentration. It has reached almost iconic status as the single number that describes how severe climate change will be. The consensus on the 'likely' range for climate sensitivity of 1.5 °C to 4.5 °C today is the same as given by Jule Charney in 1979, but now it is based on quantitative evidence from across the climate system and throughout climate history. The quest to constrain climate sensitivity has revealed important insights into the timescales of the climate system response, natural variability and limitations in observations and climate models, but also concerns about the simple concepts underlying climate sensitivity and radiative forcing, which opens avenues to better understand and constrain the climate response to forcing. Estimates of the transient climate response are better constrained by observed warming and are more relevant for predicting warming over the next decades. Newer metrics relating global warming directly to the total emitted CO2 show that in order to keep warming to within 2 °C, future CO2 emissions have to remain strongly limited, irrespective of climate sensitivity being at the high or low end.
Laboratory analysis of phacoemulsifier compliance and capacity.
Nejad, Mitra; Injev, Valentine P; Miller, Kevin M
2012-11-01
To compare the compliance and capacity of 7 fluidics modules used by 6 phacoemulsifiers from 3 manufacturers. Jules Stein Eye Institute, Los Angeles, California, USA. Experimental study. Previous-model and current-model phacoemulsifiers from 3 manufacturers were subjected to laboratory analysis of compliance and capacity. Previous-generation models tested included the Legacy Advantec, Whitestar Sovereign Phacoemulsification System, and Millennium Microsurgical System. Current models tested were the Infiniti Vision System with standard and Intrepid cassettes, Whitestar Signature Phacoemulsification System, and Stellaris Vision Enhancement System. To measure compliance, the aspiration line was connected to an electronic pressure transducer and small volumes of fluid were injected or aspirated. To measure capacity, the space between the distal end of the aspiration line and the pump was filled with methylene blue-dyed fluid. The Legacy was the most compliant phacoemulsifier. The old and new Whitestar systems, Millennium system, and Stellaris system showed similar midrange compliances. The Infiniti Vision System with the Intrepid fluidic management system was the least compliant. The Infiniti cassettes had the greatest capacity, which is a detriment from a surge-control perspective, and Signature cassettes had the least capacity. The Infiniti Intrepid system had the lowest compliance of the 6 units tested, which is optimum from a surge-control perspective. All other things being equal, the Infiniti should have the safest occlusion-break surge response. Mr. Injev is an employee of Alcon Laboratories. Dr. Miller is a consultant to and investigator for Alcon Laboratories. Ms. Nejad has no financial or proprietary interest in any material or method mentioned. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.
Voyager Interactive Web Interface to EarthScope
NASA Astrophysics Data System (ADS)
Eriksson, S. C.; Meertens, C. M.; Estey, L.; Weingroff, M.; Hamburger, M. W.; Holt, W. E.; Richard, G. A.
2004-12-01
Visualization of data is essential in helping scientists and students develop a conceptual understanding of relationships among many complex types of data and keep track of large amounts of information. Developed initially by UNAVCO for study of global-scale geodynamic processes, the Voyager map visualization tools have evolved into interactive, web-based map utilities that can make scientific results accessible to a large number and variety of educators and students as well as the originally targeted scientists. A portal to these map tools can be found at: http://jules.unavco.org. The Voyager tools provide on-line interactive data visualization through pre-determined map regions via a simple HTML/JavaScript interface (for large numbers of students using the tools simultaneously) or through student-selectable areas using a Java interface to a Generic Mapping Tools (GMT) engine. Students can access a variety of maps, satellite images, and geophysical data at a range of spatial scales for the earth and other planets of the solar system. Students can also choose from a variety of base maps (satellite mosaics, global topography, geoid, sea-floor age, strain rate and seismic hazard maps, and others) and can then add a number of geographic and geophysical overlays, for example coastlines, political boundaries, rivers and lakes, earthquake and volcano locations, stress axes, and observed and model plate motion, as well as deformation velocity vectors representing a compilation of over 5000 geodetic measurements from around the world. The related educational website, "Exploring our Dynamic Planet", (http://www.dpc.ucar.edu/VoyagerJr/jvvjrtool.html) incorporates background materials and curricular activities that encourage students to explore Earth processes. One of the present curricular modules is designed for high school students or introductory-level undergraduate non-science majors. The purpose of the module is for students to examine real data to investigate how plate tectonic processes are reflected in observed geophysical phenomena. Constructing maps by controlling map parameters and answering open-ended questions which describe, compare relationships, and work with both observed and model data, promote conceptual understanding of plate tectonics and related processes. The goals of curricular development emphasize inquiry, development of critical thinking skills, and student-centered interests. Custom editions of the map utility have been made as the "Jules Verne Voyager" and "Voyager Junior", for the International Lithosphere Project's "Global Strain Rate Map", and for EarthScope Education and Outreach as "EarthScope Voyager Jr.". For the latter, a number of EarthScope-specific features have been added, including locations of proposed USArray (seismic), Plate Boundary Observatory (geodetic), and San Andreas Fault Observatory at Depth sites, plus detailed maps and geographically referenced examples of EarthScope-related scientific investigations. As EarthScope develops, maps will be updated in `real time' so that students of all ages can use the data in formal and informal educational settings.
Cotard's Syndrome in a Patient with Schizophrenia: Case Report and Review of the Literature
Ledesma-Gastañadui, Mario
2016-01-01
Jules Cotard described, in 1880, the case of a patient characterized by delusions of negation, immortality, and guilt as well as melancholic anxiety among other clinical features. Later this constellation of symptoms was given the eponym Cotard's syndrome, going through a series of theoretical vicissitudes, considering itself currently as just the presence of nihilistic delusions. The presentation of the complete clinical features described by Cotard is a rare occurrence, especially in the context of schizophrenia. Here we present the case of a 50-year-old male patient with schizophrenia who developed Cotard's syndrome. The patient was treated with aripiprazole, showing improvement after two weeks of treatment. A review of the literature is performed about this case. PMID:28053798
Cotard's Syndrome in a Patient with Schizophrenia: Case Report and Review of the Literature.
Huarcaya-Victoria, Jeff; Ledesma-Gastañadui, Mario; Huete-Cordova, Maria
2016-01-01
Jules Cotard described, in 1880, the case of a patient characterized by delusions of negation, immortality, and guilt as well as melancholic anxiety among other clinical features. Later this constellation of symptoms was given the eponym Cotard's syndrome, going through a series of theoretical vicissitudes, considering itself currently as just the presence of nihilistic delusions. The presentation of the complete clinical features described by Cotard is a rare occurrence, especially in the context of schizophrenia. Here we present the case of a 50-year-old male patient with schizophrenia who developed Cotard's syndrome. The patient was treated with aripiprazole, showing improvement after two weeks of treatment. A review of the literature is performed about this case.
Trends in evaporation loss over the UK: 1962 to 2013
NASA Astrophysics Data System (ADS)
Blyth, Eleanor; Robinson, Emma; Martinez de la Torre, Alberto
2017-04-01
Many models of hydrology assume that an increase in air temperature will result in an increase in evaporation. However, there are some processes involved in transpiration (evaporation through the vegetation) that make the relationship more complicated: in a bid to conserve water, vegetation will reduce their stomata in response to drier soils and warmer drier air which leads to lower transpiration rates despite higher evaporative demands. In addition, the vegetation responds to increases in atmospheric carbon dioxide by closing their stomata, and this further reduces the transpiration. The JULES (Joint UK Land Environment Simulator) model, used widely in the UK to study the impacts of climate change on the environment, includes many of the processes that are likely to affect changes in water loss and its impact on large scale hydrology. A new assessment of the UK wide water balance for the last 52 years (1961 to 2013) at a 1km grid-scale has been made using this model in a system called CHESS (Climate Hydrology and Ecology research Support System). Some data is available to check the overall water balance. For instance, river flow data can be used at an annual time scale to capture the water balance, while evaporation data from flux towers can be used at some locations around the UK for the few years that it is available to evaluate the seasonal variations of evaporation. Both of these methods provide imperfect but useful evidence. Here we present the results of the modelling exercise and the evaluation: long term increasing evaporation loss trends are clearly present in the model output and these are discussed with respect to the different drivers of change.
NASA Astrophysics Data System (ADS)
2012-10-01
Many AGU members are among the American Meteorological Society's (AMS) 2013 honorary members, awardees, lecturers, and fellows. Among the AMS honorary members is Susan Solomon, the Ellen Swallow Richards Professor of Atmospheric Chemistry and Climate Science at the Massachusetts Institute of Technology (MIT). Dennis Hartmann, of the University of Washington, Seattle, is the recipient of AMS's Carl-Gustaf Rossby Research Medal “for significant contributions to the synthesis of knowledge of radiative and dynamical processes leading to a deeper understanding of the climate system.” R. Alan Plumb, professor of meteorology at MIT, receives the Jule G. Charney Award “for fundamental contributions to the understanding of geophysical fluid dynamics, stratospheric dynamics, chemical transport, and the general circulation of the atmosphere and oceans.” The Verner E. Suomi Award has been given to Richard Johnson, professor of atmospheric science at Colorado State University, Fort Collins, “for exquisite design of rawinsonde networks in field campaigns and insightful analysis of interactions between convective clouds and the largescale atmospheric circulation.” W. Kendall Melville, professor of oceanography at the Scripps Institution of Oceanography, University of California, San Diego, has been awarded the Sverdrup Gold Medal Award “for pioneering contributions in advancing knowledge on the role of surface wave breaking and related processes in air-sea interaction.” AMS announced that Laurence Armi, also a professor of oceanography at Scripps, is recipient of the Henry Stommel Research Award “for his deeply insightful studies of stratified flow, his pioneering work on boundary mixing and other turbulent mechanisms.”
NASA Astrophysics Data System (ADS)
Liu, Y.; Rollinson, C.; Dietze, M.; McLachlan, J. S.; Poulter, B.; Quaife, T. L.; Raiho, A.; Ricciuto, D. M.; Schaefer, K. M.; Steinkamp, J.; Moore, D. J.
2015-12-01
Over multi-decadal to multi-centennial timescales, ecosystem function and carbon storage is largely influenced by vegetation composition. The predictability of ecosystem responses to climate change thus depends on the understanding of long-term community dynamics. Our study aims to quantify the influence of the most relevant ecological factors that control plant distribution and abundance, in contemporary terrestrial biosphere models and in paleo-records, and constrain the model processes and parameters with paleoecological data. We simulated vegetation changes at 6 sites in the northeastern United States over the past 1160 years using 7 terrestrial biosphere models and variations (CLM4.5-CN, ED2, ED2-LU, JULES-TRIFFID, LINKAGES, LPJ-GUESS, LPJ-wsl) driven by common paleoclimatic drivers. We examined plant growth, recruitment, and mortality (including other carbon turnover) of the plant functional types (PFTs) in the models, attributed the responses to three major factors (climate, competition, and disturbance), and estimated the relative effect of each factor. We assessed the model responses against plant-community theories (bioclimatic limits, niche difference, temporal variation and storage effect, and disturbance). We found that vegetation composition were sensitive to realized niche differences (e.g. differential growth response) among PFTs. Because many models assume unlimited dispersal and sometimes recruitment, the "storage effect" constantly affects community composition. Fire was important in determining the ecosystem composition, yet the vegetation to fire feedback was weak in the models. We also found that vegetation-composition changes in the simulations were driven to a much greater degree by growth as opposed to by turnover/mortality, when compared with those in paleoecological records. Our work suggest that 1) for forecasting slow changes in vegetation composition, we can use paleo-data to better quantify the realized niches of PFTs and associated uncertainties, and 2) for predicting abrupt changes in vegetation composition, we need to better implement processes of dynamic turnover and fire in current ecosystem models.
Plant Nitrogen Uptake in Terrestrial Biogeochemical Models
NASA Astrophysics Data System (ADS)
Marti, Alejandro; Cox, Peter; Sitch, Stephen; Jones, Chris; Liddicoat, spencer
2013-04-01
Most terrestrial biogeochemical models featured in the last Intergovernmental Panel on Climate Change (IPPC) Assessment Report highlight the importance of the terrestrial Carbon sequestration and feedbacks between the terrestrial Carbon cycle and the climate system. However, these models have been criticized for overestimating predicted Carbon sequestration and its potential climate feedback when calculating the rate of future climate change because they do not account for the Carbon sequestration constraints caused by nutrient limitation, particularly Nitrogen (N). This is particularly relevant considering the existence of a substantial deficit of Nitrogen for plants in most areas of the world. To date, most climate models assume that plants have access to as much Nitrogen as needed, but ignore the nutrient requirements for new vegetation growth. Determining the natural demand and acquisition for Nitrogen and its associated resource optimization is key when accounting for the Carbon sequestration constrains caused by nutrient limitation. The few climate models that include C-N dynamics have illustrated that the stimulation of plant growth over the coming century may be two to three times smaller than previously predicted. This reduction in growth is partially offset by an increase in the availability of nutrients resulting from an accelerated rate of decomposition of dead plants and other organic matter that occurring with a rise in temperature. However, this offset does not counterbalance the reduced level of plant growth calculated by natural nutrient limitations. Additionally, Nitrogen limitation is also expected to become more pronounced in some ecosystems as atmospheric CO2 concentration increases; resulting in less new growth and higher atmospheric CO2 concentrations than originally expected. This study compares alternative models of plant N uptake as found in different terrestrial biogeochemical models against field measurements, and introduces a new N-uptake model to the Joint UK Land Environment Simulator (JULES).. Acknowledgements This work has been funded by the European Commission FP7-PEOPLE-ITN-2008 Marie Curie Action: "Greencycles II: FP7-PEOPLE-ITN-2008 Marie Curie Action: "Networks for Initial Training"
Arnaud, Pascal
2015-03-01
Through some examples of his works, realized between 1833 and 1845 (studies on the tannin, the reaction of etherification, and on the nature of the chemical function of the glycerin), this article tries to bring to light his scientific approach. This one is not only based on the immediate analysis and the elementary analysis, but also on the study of characteristic chemical reactions, which are going to give him information onto the chemical nature and the constitution of the molecules which he studies. This approach will lead him finally to use these reactions not only in an analytical purpose but also in a purpose of synthesis.
2015-01-06
CAPE CANAVERAL, Fla. -- NASA Administrator Charlie Bolden looked over the agency's Orion spacecraft this morning for the first time since it returned to Kennedy Space Center following the successful Orion flight test on Dec. 5. At right is Jules Schneider, Lockheed Martin manager. At left is Kennedy Space Center Associate Director Kelvin Manning. Bearing the marks of a spacecraft that has returned to Earth through a searing plunge into the atmosphere, Orion is perched on a pedestal inside the Launch Abort System Facility at Kennedy where it is going through post-mission processing. Although the spacecraft Bolden looked over did not fly with a crew aboard during the flight test, Orion is designed to carry astronauts into deep space in the future setting NASA and the nation firmly on the journey to Mars. Photo credit: NASA/Cory Huston
2012-08-23
CAPE CANAVERAL, Fla. - In the Operations and Checkout Building at the Kennedy Space Center in Florida, NASA Administrator Charles Bolden, center, addresses news media in front of the Orion EFT-1 spacecraft. Also participating are Jules Schneider, senior manager of Project Engineering for the Lockheed Martin Orion Program at Kennedy, left, and Scott Wilson, NASA's manager of Production Operations for the Orion Program. Bolden took a few dozen members of the news media on a tour of the space agency's Kennedy Space Center and adjacent Cape Canaveral Air Force Station on Aug. 23, 2012 to show the progress being made for future government and commercial space endeavors that will begin from Florida's Space Coast. For more information, visit: http://www.nasa.gov/centers/kennedy/news/kennedy-bolden-tour.html Photo credit: NASA/Kim Shiflett
2014-12-19
CAPE CANAVERAL, Fla. -- NASA's Orion spacecraft is viewed by members of the media at the Launch Abort System Facility at NASA's Kennedy Space Center in Florida. Speaking to the media during the viewing opportunity is Jules Schneider, Lockheed Martin Manager. Behind him, from left, are Glenn Chin, Orion Production Operations manager and Phil Weber and Lou Garcia, with the Ground Systems Development and Operations Program, or GSDO. Orion made the 8-day, 2,700 mile overland trip back to Kennedy from Naval Base San Diego in California. Analysis of date obtained during its two-orbit, four-and-a-half hour mission Dec. 5 will provide engineers with detailed information on how the spacecraft fared. GSDO led the recovery, offload and transportation efforts. For more information, visit www.nasa.gov/orion. Photo credit: NASA/Dimitri Gerondidakis
2014-12-19
CAPE CANAVERAL, Fla. -- NASA's Orion spacecraft is viewed by members of the media at the Launch Abort System Facility at NASA's Kennedy Space Center in Florida. Speaking to the media during the viewing opportunity is Phil Weber, with the Ground Systems Development and Operations Program, or GSDO. At left is Jules Schneider, Lockheed Martin manager. At right is Glenn Chin, Orion Production Operations, and Lou Garcia, with GSDO. Orion made the 8-day, 2,700 mile overland trip back to Kennedy from Naval Base San Diego in California. Analysis of date obtained during its two-orbit, four-and-a-half hour mission Dec. 5 will provide engineers detailed information on how the spacecraft fared. GSDO led the recovery, offload and transportation efforts. For more information, visit www.nasa.gov/orion. Photo credit: NASA/Dimitri Gerondidakis
Augusta Déjerine-Klumpke: the first female neuroanatomist.
Shoja, Mohammadali M; Tubbs, R Shane
2007-08-01
Augusta Déjerine-Klumpke, the wife of Joseph Jules Dejerine, an eminent French neurologist, was an American and the first woman to intern in a Parisian hospital. She is known for Klumpke's radicular palsy, which is a neuropathy involving the lower nerve roots of the brachial plexus. The neuroanatomical treatise that she wrote together with her husband is considered a masterpiece. Klumpke won several awards in medical science, the first of which was in the field of anatomy when she was a student. She was a pioneer of rehabilitation therapy after spinal cord injuries and contributed much to our current knowledge of spinal cord diseases. We review the current English and French literature regarding this neuroanatomist who was the first woman to directly contribute to the writing of a neuroanatomy textbook.
The Klumpke family--memories by Doctor Déjerine, born Augusta Klumpke.
Bogousslavsky, Julien
2005-01-01
In this paper, we present a translation of an unpublished autobiographical document by Augusta Déjerine-Klumpke, reporting her early years before she came to Paris to study medicine, when she was able to become one of the first women in France to hold a hospital position, as an extern and an intern. This American-born girl later married Jules Déjerine, who was to become the second successor to Charcot at La Salpétrière 23 years later. The present document gives a vivid account on the preceding years, and emphasizes the extraordinary dynamism and enthusiasm of a young woman, whose efforts and contributions influenced neurology at the turn of the 20th century, and dramatically changed the role of women in medical careers.
NASA Astrophysics Data System (ADS)
Moebius, B.; Pfennigbauer, M.; Pereira do Carmo, J.
2017-11-01
During the previous 15 years, Rendezvous and Docking Sensors (RVS) were developed, manufactured and qualified. In the mean time they were successfully applied in some space missions: For automatic docking of the European ATV "Jules Verne" on the International Space Station in 2008; for automatic berthing of the first Japanese HTV in 2009, and even the precursor model ARP-RVS for measurements during Shuttle Atlantis flights STS-84 and STS-86 to the MIR station. Up to now, about twenty RVS Flight Models for application on ATV, HTV and the American Cygnus Spacecraft were manufactured and delivered to the respective customers. RVS is designed for tracking of customer specific, cooperative targets (i.e. retro reflectors that are arranged in specific geometries). Once RVS has acquired the target, the sensor measures the distance to the target by timeof- flight determination of a pulsed laser beam. Any echo return provokes an interrupt signal and thus the readout of the according encoder positions of the two scan mirrors that represent Azimuth and Elevation measurement direction to the target. [2], [3]. The capability of the RVS for 3D mapping of the scene makes the fully space qualified RVS to be real 3D Lidar sensors; thus they are a sound technical base for the compact 3D Lidar breadboard that was developed in the course of the Imaging Lidar Technology (ILT) project.
NASA Astrophysics Data System (ADS)
Terranova, Nicholas; Serot, Olivier; Archier, Pascal; De Saint Jean, Cyrille; Sumini, Marco
2017-09-01
Fission product yields (FY) are fundamental nuclear data for several applications, including decay heat, shielding, dosimetry, burn-up calculations. To be safe and sustainable, modern and future nuclear systems require accurate knowledge on reactor parameters, with reduced margins of uncertainty. Present nuclear data libraries for FY do not provide consistent and complete uncertainty information which are limited, in many cases, to only variances. In the present work we propose a methodology to evaluate covariance matrices for thermal and fast neutron induced fission yields. The semi-empirical models adopted to evaluate the JEFF-3.1.1 FY library have been used in the Generalized Least Square Method available in CONRAD (COde for Nuclear Reaction Analysis and Data assimilation) to generate covariance matrices for several fissioning systems such as the thermal fission of U235, Pu239 and Pu241 and the fast fission of U238, Pu239 and Pu240. The impact of such covariances on nuclear applications has been estimated using deterministic and Monte Carlo uncertainty propagation techniques. We studied the effects on decay heat and reactivity loss uncertainty estimation for simplified test case geometries, such as PWR and SFR pin-cells. The impact on existing nuclear reactors, such as the Jules Horowitz Reactor under construction at CEA-Cadarache, has also been considered.
Large uncertainty in carbon uptake potential of land-based climate-change mitigation efforts.
Krause, Andreas; Pugh, Thomas A M; Bayer, Anita D; Li, Wei; Leung, Felix; Bondeau, Alberte; Doelman, Jonathan C; Humpenöder, Florian; Anthoni, Peter; Bodirsky, Benjamin L; Ciais, Philippe; Müller, Christoph; Murray-Tortarolo, Guillermo; Olin, Stefan; Popp, Alexander; Sitch, Stephen; Stehfest, Elke; Arneth, Almut
2018-07-01
Most climate mitigation scenarios involve negative emissions, especially those that aim to limit global temperature increase to 2°C or less. However, the carbon uptake potential in land-based climate change mitigation efforts is highly uncertain. Here, we address this uncertainty by using two land-based mitigation scenarios from two land-use models (IMAGE and MAgPIE) as input to four dynamic global vegetation models (DGVMs; LPJ-GUESS, ORCHIDEE, JULES, LPJmL). Each of the four combinations of land-use models and mitigation scenarios aimed for a cumulative carbon uptake of ~130 GtC by the end of the century, achieved either via the cultivation of bioenergy crops combined with carbon capture and storage (BECCS) or avoided deforestation and afforestation (ADAFF). Results suggest large uncertainty in simulated future land demand and carbon uptake rates, depending on the assumptions related to land use and land management in the models. Total cumulative carbon uptake in the DGVMs is highly variable across mitigation scenarios, ranging between 19 and 130 GtC by year 2099. Only one out of the 16 combinations of mitigation scenarios and DGVMs achieves an equivalent or higher carbon uptake than achieved in the land-use models. The large differences in carbon uptake between the DGVMs and their discrepancy against the carbon uptake in IMAGE and MAgPIE are mainly due to different model assumptions regarding bioenergy crop yields and due to the simulation of soil carbon response to land-use change. Differences between land-use models and DGVMs regarding forest biomass and the rate of forest regrowth also have an impact, albeit smaller, on the results. Given the low confidence in simulated carbon uptake for a given land-based mitigation scenario, and that negative emissions simulated by the DGVMs are typically lower than assumed in scenarios consistent with the 2°C target, relying on negative emissions to mitigate climate change is a highly uncertain strategy. © 2018 John Wiley & Sons Ltd.
Thurner, Martin; Beer, Christian; Ciais, Philippe; Friend, Andrew D; Ito, Akihiko; Kleidon, Axel; Lomas, Mark R; Quegan, Shaun; Rademacher, Tim T; Schaphoff, Sibyll; Tum, Markus; Wiltshire, Andy; Carvalhais, Nuno
2017-08-01
Turnover concepts in state-of-the-art global vegetation models (GVMs) account for various processes, but are often highly simplified and may not include an adequate representation of the dominant processes that shape vegetation carbon turnover rates in real forest ecosystems at a large spatial scale. Here, we evaluate vegetation carbon turnover processes in GVMs participating in the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP, including HYBRID4, JeDi, JULES, LPJml, ORCHIDEE, SDGVM, and VISIT) using estimates of vegetation carbon turnover rate (k) derived from a combination of remote sensing based products of biomass and net primary production (NPP). We find that current model limitations lead to considerable biases in the simulated biomass and in k (severe underestimations by all models except JeDi and VISIT compared to observation-based average k), likely contributing to underestimation of positive feedbacks of the northern forest carbon balance to climate change caused by changes in forest mortality. A need for improved turnover concepts related to frost damage, drought, and insect outbreaks to better reproduce observation-based spatial patterns in k is identified. As direct frost damage effects on mortality are usually not accounted for in these GVMs, simulated relationships between k and winter length in boreal forests are not consistent between different regions and strongly biased compared to the observation-based relationships. Some models show a response of k to drought in temperate forests as a result of impacts of water availability on NPP, growth efficiency or carbon balance dependent mortality as well as soil or litter moisture effects on leaf turnover or fire. However, further direct drought effects such as carbon starvation (only in HYBRID4) or hydraulic failure are usually not taken into account by the investigated GVMs. While they are considered dominant large-scale mortality agents, mortality mechanisms related to insects and pathogens are not explicitly treated in these models. © 2017 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
François, Louis; Henrot, Alexandra-Jane; Dury, Marie; Jacquemin, Ingrid; Munhoven, Guy; Friend, Andrew; Rademacher, Tim T.; Hacket Pain, Andrew J.; Hickler, Thomas; Tian, Hanqin; Morfopoulos, Catherine; Ostberg, Sebastian; Chang, Jinfeng; Rafique, Rashid; Nishina, Kazuya
2016-04-01
According to the projections of climate models, extreme events such as droughts and heat waves are expected to become more frequent and more severe in the future. Such events are known to severely impact the productivity of both natural and agricultural ecosystems, and hence to affect ecosystem services such as crop yield and ecosystem carbon sequestration potential. Dynamic vegetation models are conventional tools to evaluate the productivity and carbon sequestration of ecosystems and their response to climate change. However, how far are these models able to correctly represent the sensitivity of ecosystems to droughts and heat waves? How do the responses of natural and agricultural ecosystems compare to each other, in terms of drought-induced changes in productivity and carbon sequestration? In this contribution, we use ISI-MIP2 model historical simulations from the biome sector to tentatively answer these questions. Nine dynamic vegetation models have participated in the biome sector intercomparison of ISI-MIP2: CARAIB, DLEM, HYBRID, JULES, LPJ-GUESS, LPJml, ORCHIDEE, VEGAS and VISIT. We focus the analysis on well-marked droughts or heat waves that occured in Europe after 1970, such as the 1976, 2003 and 2010 events. For most recent studied events, the model results are compared to the response observed at several eddy covariance sites in Europe, and, at a larger scale, to the changes in crop productivities reported in national statistics or to the drought impacts on gross primary productivity derived from satellite data (Terra MODIS instrument). The sensitivity of the models to the climatological dataset used in the simulations, as well as to the inclusion or not of anthropogenic land use, is also analysed within the studied events. Indeed, the ISI-MIP simulations have been run with four different historical climatic forcings, as well as for several land use/land cover configurations (natural vegetation, fixed land use and variable land use).
Calculation to experiment comparison of SPND signals in various nuclear reactor environments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barbot, Loic; Radulovic, Vladimir; Fourmentel, Damien
2015-07-01
In the perspective of irradiation experiments in the future Jules Horowitz Reactor (JHR), the Instrumentation Sensors and Dosimetry Laboratory of CEA Cadarache (France) is developing a numerical tool for SPND design, simulation and operation. In the frame of the SPND numerical tool qualification, dedicated experiments have been performed both in the Slovenian TRIGA Mark II reactor (JSI) and very recently in the French CEA Saclay OSIRIS reactor, as well as a test of two detectors in the core of the Polish MARIA reactor (NCBJ). A full description of experimental set-ups and neutron-gamma calculations schemes are provided in the first partmore » of the paper. Calculation to experiment comparison of the various SPNDs in the different reactors is thoroughly described and discussed in the second part. Presented comparisons show promising final results. (authors)« less
Restoration of an old telescope: a pedagogic opportunity
NASA Astrophysics Data System (ADS)
Le Gall, Christophe
2016-04-01
The "Lycée Jules Haag" High School is a former clockwork learning school. It has a telescope, built in the 1930's, which was used to calibrate time for watches. Nowadays, this telescope is no longer of any practical use, and has been classified for its historical interest. Thanks to the financial help of local companies, a new pedagogic project has started inside our school. This astronomical device is going to be repaired, and many teachers and classes will be involved. This will create opportunities during and after the restoration. Our High School will have practical classes that may work around the motorisation of the telescope and creating a new eyepiece. When the telescope is operational, we can use this device for physics and optics classes, and organise an astronomical club to do some day and night observations.
2014-08-22
CAPE CANAVERAL, Fla. – NASA astronauts tour the Neil Armstrong Operations and Checkout Building high bay at NASA's Kennedy Space Center in Florida, and view the Orion forward bay cover for Exploration Flight Test-1. From left, are Jack Fischer, Mark Vande Hei, Katie Rubins and Scott Tingle. At far right is Jules Schneider, Lockheed Martin senior manager. Orion is the exploration spacecraft designed to carry astronauts to destinations not yet explored by humans, including an asteroid and Mars. It will have emergency abort capability, sustain the crew during space travel and provide safe re-entry from deep space return velocities. The first unpiloted test flight of Orion is scheduled to launch in 2014 atop a United Launch Alliance Delta IV rocket and in 2018 on NASA’s Space Launch System rocket. For more information, visit www.nasa.gov/orion. Photo credit: Dimitri Gerondidakis
MPL Guwahati and extraction of aerosol and dust features
NASA Astrophysics Data System (ADS)
Devi, M.; Baishy, R.; Barbara, A.
Aerosols emitted directly from natural and anthropogenic sources are responsible for bringing changes in atmospheric conditions and in modifying physical and dynamical processes therein. With the aim to correlate such changes in atmospheric environments with aerosols, a MPL Lidar has been put into operation at Gauhati University a subtropical station, where atmospheric variabilities are subjected to the influence of its complex local topography and man made system inhomogenities. The Lidar that is in operation at Gauhati University since January 2001, has been developed in collaboration with Chiba University, Japan. This portable instrument consists of a low power (>20 μ Jule) 10 ns pulse laser at 532 nm with PRF varying from 1 to 5 KHz. The receiver consists of a 0.2 m aperture case grain telescope with 1nm filter and the PMT working in photon counting mode. The signal acquisition is done in LabVIEW environment and processing is made through a user-friendlyn software also in LabVIEW environment developed by this group. The aerosol and dust signatures received through routine sounding are analyzed for extinction and backscattered cross section parameters and attempts are made for evaluating significant features in backscattered signal from dust particles which are well detected in the lidar echogram during early spring. The paper also discusses the techniques for evaluation of system constant "C" before presenting cross section parameters. The approach is through horizontal probing of the atmosphere and assuming same type of aerosol population over a defined (near surface) altitude. The "C" value so obtained, comes close to the figure calculated from relation,
Zhang, Ke; de Almeida Castanho, Andrea D; Galbraith, David R; Moghim, Sanaz; Levine, Naomi M; Bras, Rafael L; Coe, Michael T; Costa, Marcos H; Malhi, Yadvinder; Longo, Marcos; Knox, Ryan G; McKnight, Shawna; Wang, Jingfeng; Moorcroft, Paul R
2015-02-20
There is considerable interest in understanding the fate of the Amazon over the coming century in the face of climate change, rising atmospheric CO 2 levels, ongoing land transformation, and changing fire regimes within the region. In this analysis, we explore the fate of Amazonian ecosystems under the combined impact of these four environmental forcings using three terrestrial biosphere models (ED2, IBIS, and JULES) forced by three bias-corrected IPCC AR4 climate projections (PCM1, CCSM3, and HadCM3) under two land-use change scenarios. We assess the relative roles of climate change, CO 2 fertilization, land-use change, and fire in driving the projected changes in Amazonian biomass and forest extent. Our results indicate that the impacts of climate change are primarily determined by the direction and severity of projected changes in regional precipitation: under the driest climate projection, climate change alone is predicted to reduce Amazonian forest cover by an average of 14%. However, the models predict that CO 2 fertilization will enhance vegetation productivity and alleviate climate-induced increases in plant water stress, and, as a result, sustain high biomass forests, even under the driest climate scenario. Land-use change and climate-driven changes in fire frequency are predicted to cause additional aboveground biomass loss and reductions in forest extent. The relative impact of land use and fire dynamics compared to climate and CO 2 impacts varies considerably, depending on both the climate and land-use scenario, and on the terrestrial biosphere model used, highlighting the importance of improved quantitative understanding of all four factors - climate change, CO 2 fertilization effects, fire, and land use - to the fate of the Amazon over the coming century. © 2015 John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Burke, Eleanor J.; Chadburn, Sarah E.; Huntingford, Chris; Jones, Chris D.
2018-02-01
Large amounts of carbon are stored in the permafrost of the northern high latitude land. As permafrost degrades under a warming climate, some of this carbon will decompose and be released to the atmosphere. This positive climate-carbon feedback will reduce the natural carbon sinks and thus lower anthropogenic CO2 emissions compatible with the goals of the Paris Agreement. Simulations using an ensemble of the JULES-IMOGEN intermediate complexity climate model (including climate response and process uncertainty) and a stabilization target of 2 °C, show that including the permafrost carbon pool in the model increases the land carbon emissions at stabilization by between 0.09 and 0.19 Gt C year-1 (10th to 90th percentile). These emissions are only slightly reduced to between 0.08 and 0.16 Gt C year-1 (10th to 90th percentile) when considering 1.5 °C stabilization targets. This suggests that uncertainties caused by the differences in stabilization target are small compared with those associated with model parameterisation uncertainty. Inertia means that permafrost carbon loss may continue for many years after anthropogenic emissions have stabilized. Simulations suggest that between 225 and 345 Gt C (10th to 90th percentile) are in thawed permafrost and may eventually be released to the atmosphere for stabilization target of 2 °C. This value is 60-100 Gt C less for a 1.5 °C target. The inclusion of permafrost carbon will add to the demands on negative emission technologies which are already present in most low emissions scenarios.
Restrepo-Coupe, Natalia; Levine, Naomi M.; Christoffersen, Bradley O.; ...
2016-08-29
To predict forest response to long-term climate change with high confidence requires that dynamic global vegetation models (DGVMs) be successfully tested against ecosystem response to short-term variations in environmental drivers, including regular seasonal patterns. Here, we used an integrated dataset from four forests in the Brasil flux network, spanning a range of dry-season intensities and lengths, to determine how well four state-of-the-art models (IBIS, ED2, JULES, and CLM3.5) simulated the seasonality of carbon exchanges in Amazonian tropical forests. We found that most DGVMs poorly represented the annual cycle of gross primary productivity (GPP), of photosynthetic capacity (Pc), and of othermore » fluxes and pools. Models simulated consistent dry-season declines in GPP in the equatorial Amazon (Manaus K34, Santarem K67, and Caxiuanã CAX); a contrast to observed GPP increases. Model simulated dry-season GPP reductions were driven by an external environmental factor, ‘soil water stress’ and consequently by a constant or decreasing photosynthetic infrastructure (Pc), while observed dry-season GPP resulted from a combination of internal biological (leaf-flush and abscission and increased Pc) and environmental (incoming radiation) causes. Moreover, we found models generally overestimated observed seasonal net ecosystem exchange (NEE) and respiration (Re) at equatorial locations. In contrast, a southern Amazon forest (Jarú RJA) exhibited dry-season declines in GPP and Re consistent with most DGVMs simulations. While water limitation was represented in models and the primary driver of seasonal photosynthesis in southern Amazonia, changes in internal biophysical processes, light-harvesting adaptations (e.g., variations in leaf area index (LAI) and increasing leaf-level assimilation rate related to leaf demography), and allocation lags between leaf and wood, dominated equatorial Amazon carbon flux dynamics and were deficient or absent from current model formulations. In conclusion, correctly simulating flux seasonality at tropical forests requires a greater understanding and the incorporation of internal biophysical mechanisms in future model developments.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Restrepo-Coupe, Natalia; Levine, Naomi M.; Christoffersen, Bradley O.
To predict forest response to long-term climate change with high confidence requires that dynamic global vegetation models (DGVMs) be successfully tested against ecosystem response to short-term variations in environmental drivers, including regular seasonal patterns. Here, we used an integrated dataset from four forests in the Brasil flux network, spanning a range of dry-season intensities and lengths, to determine how well four state-of-the-art models (IBIS, ED2, JULES, and CLM3.5) simulated the seasonality of carbon exchanges in Amazonian tropical forests. We found that most DGVMs poorly represented the annual cycle of gross primary productivity (GPP), of photosynthetic capacity (Pc), and of othermore » fluxes and pools. Models simulated consistent dry-season declines in GPP in the equatorial Amazon (Manaus K34, Santarem K67, and Caxiuanã CAX); a contrast to observed GPP increases. Model simulated dry-season GPP reductions were driven by an external environmental factor, ‘soil water stress’ and consequently by a constant or decreasing photosynthetic infrastructure (Pc), while observed dry-season GPP resulted from a combination of internal biological (leaf-flush and abscission and increased Pc) and environmental (incoming radiation) causes. Moreover, we found models generally overestimated observed seasonal net ecosystem exchange (NEE) and respiration (Re) at equatorial locations. In contrast, a southern Amazon forest (Jarú RJA) exhibited dry-season declines in GPP and Re consistent with most DGVMs simulations. While water limitation was represented in models and the primary driver of seasonal photosynthesis in southern Amazonia, changes in internal biophysical processes, light-harvesting adaptations (e.g., variations in leaf area index (LAI) and increasing leaf-level assimilation rate related to leaf demography), and allocation lags between leaf and wood, dominated equatorial Amazon carbon flux dynamics and were deficient or absent from current model formulations. In conclusion, correctly simulating flux seasonality at tropical forests requires a greater understanding and the incorporation of internal biophysical mechanisms in future model developments.« less
NASA Astrophysics Data System (ADS)
Churkina, G.; Zaehle, S.; Hughes, J.; Viovy, N.; Chen, Y.; Jung, M.; Heumann, B. W.; Ramankutty, N.; Rödenbeck, C.; Heimann, M.; Jones, C.
2010-03-01
European ecosystems are thought to uptake significant amounts of carbon, but neither the rate nor the contributions of the underlying processes are well known. In the second half of the 20th century, carbon dioxide concentrations have risen by more than 100 ppm, atmospheric nitrogen deposition has more than doubled, and European mean temperatures were increasing by 0.02 °C per year. The extents of forest and grasslands have increase with the respective rates of 5800 km2 yr-1 and 1100 km2 yr-1 as agricultural land has been abandoned at a rate of 7000 km2 yr-1. In this study, we analyze the responses of European land ecosystems to the aforementioned environmental changes using results from four process-based ecosystem models: BIOME-BGC, JULES, ORCHIDEE, and O-CN. All four models suggest that European terrestrial ecosystems sequester carbon at a rate of 100 TgC yr-1 (1980-2007 mean) with strong interannual variability (± 85 TgC yr-1) and a substantial inter-model uncertainty (± 45 TgC yr-1). Decadal budgets suggest that there has been a slight increase in terrestrial net carbon storage from 85 TgC yr-1 in 1980-1989 to 114 TgC yr-1 in 2000-2007. The physiological effect of rising CO2 in combination with nitrogen deposition and forest re-growth have been identified as the important explanatory factors for this net carbon storage. Changes in the growth of woody vegetation are an important contributor to the European carbon sink. Simulated ecosystem responses were more consistent for the two models accounting for terrestrial carbon-nitrogen dynamics than for the two models which only accounted for carbon cycling and the effects of land cover change. Studies of the interactions of carbon-nitrogen dynamics with land use changes are needed to further improve the quantitative understanding of the driving forces of the European land carbon balance.
NASA Astrophysics Data System (ADS)
van Eck, C. M.; Morfopoulos, C.; Betts, R. A.; Chang, J.; Ciais, P.; Friedlingstein, P.; Regnier, P. A. G.
2016-12-01
The frequency and severity of extreme climate events such as droughts, extreme precipitation and heatwaves are expected to increase in our changing climate. These extreme climate events will have an effect on vegetation either by enhanced or reduced productivity. Subsequently, this can have a substantial impact on the terrestrial carbon sink and thus the global carbon cycle, especially as extreme climate events are expected to increase in frequency and severity. Connecting observational datasets with modelling studies provides new insights into these climate-vegetation interactions. This study aims to compare extremes in vegetation productivity as derived from observations with that of Dynamic Global Vegetation Models (DGVMs). In this case GIMMS-NDVI 3g is selected as the observational dataset and both JULES (Joint UK Land Environment Simulator) and ORCHIDEE (Organising Carbon and Hydrology In Dynamic Ecosystems) as the DGVMs. Both models are forced with PGFv2 Global Meteorological Forcing Dataset according to the ISI-MIP2 protocol for historical runs. Extremes in vegetation productivity are the focal point, which are identified as NDVI anomalies below the 10th percentile or above the 90th percentile during the growing season, referred to as browning or greening events respectively. The monthly NDVI dataset GIMMS-NDVI 3g is used to obtain the location in time and space of the vegetation extremes. The global GIMMS-NDVI 3g dataset has been subdivided into IPCC's SREX-regions for which the NDVI anomalies are calculated and the extreme thresholds are determined. With this information we can identify the location in time and space of the browning and greening events in remotely-sensed vegetation productivity. The same procedure is applied to the modelled Gross Primary Productivity (GPP) allowing a comparison between the spatial and temporal occurrence of the browning and greening events in the observational dataset and the models' output. The capacity of the models to catch observed extremes in vegetation productivity is assessed and compared. Factors contributing to observed and modelled vegetation browning/greening extremes are analysed. The results of this study provide a stepping stone to modelling future extremes in vegetation productivity.
2015-01-06
CAPE CANAVERAL, Fla. -- NASA Administrator Charlie Bolden, third from right, looked over the agency's Orion spacecraft this morning for the first time since it returned to Kennedy Space Center following the successful Orion flight test on Dec. 5. At far right is Jules Schneider, Lockheed Martin manager. Standing near Bolden is Paul Cooper, a Lockheed Martin manager. At far left is Kennedy Space Center Associate Director Kelvin Manning. Bearing the marks of a spacecraft that has returned to Earth through a searing plunge into the atmosphere, Orion is perched on a pedestal inside the Launch Abort System Facility at Kennedy where it is going through post-mission processing. Although the spacecraft Bolden looked over did not fly with a crew aboard during the flight test, Orion is designed to carry astronauts into deep space in the future setting NASA and the nation firmly on the journey to Mars. Photo credit: NASA/Cory Huston
De Berardis, Domenico; Brucchi, Maurizio; Serroni, Nicola; Rapini, Gabriella; Campanella, Daniela; Vellante, Federica; Valchera, Alessandro; Fornaro, Michele; Iasevoli, Felice; Mazza, Monica; Lucidi, Giuliana; Martinotti, Giovanni; di Giannantonio, Massimo
2015-01-01
In 1880 the French neurologist Jules Cotard described a condition characterized by delusion of negation (nihilistic delusion) in a melancholia context. Recently, there has been a resurgence of interest in Cotard's syndrome (CS), but the nosographical figure of CS remains unclear. It isn't determined if it pertains to the delusional themes area or if it is related to the sense of immanent ruin in some depressive episodes. For these reasons CS has recently been supposed to be an intermediate form. Furthermore, since even less is known about secondary CS in subjects who had never suffered of psychiatric disorders, in the present case we report the development of a secondary CS in a female patient who underwent a lumpectomy for the removal of a benign fibroadenoma. The patient responded well to aripiprazole augmentation of escitalopram and totally remitted.
2013-06-20
CAPE CANAVERAL, Fla. – Representatives from the European Space Agency, or ESA, toured the Operations and Checkout Building high bay at NASA’s Kennedy Space Center in Florida. Pointing at thermal protection system tiles is Jules Schneider, Lockheed Martin senior manager. At right, in the blue suit, is Bernardo Patti, ESA manager of International Space Station Operations. Standing next to Patti is Nico Dettman, ESA Space Transportation Department director. Orion is the exploration spacecraft designed to carry crews to space beyond low Earth orbit. It will provide emergency abort capability, sustain the crew during the space travel and provide safe re-entry from deep space return velocities. Orion’s first unpiloted test flight is scheduled to launch in 2014 atop a Delta IV rocket. A second uncrewed flight test is scheduled for 2017 on NASA’s Space Launch System rocket. For more information, visit http://www.nasa.gov/orion. Photo credit: NASA/Jim Grossmann
The first international leprosy conference, Berlin, 1897: the politics of segregation.
Pandya, S S
2004-01-01
The present paper examines the first attempts to internationalise the problem of leprosy, a subject hitherto overlooked by historians of imperialism and disease. The last decade of the nineteenth century saw many in the civilised countries of the imperialist West gripped by a paranoia about an invasion of leprosy via germ-laden immigrants and returning expatriates who had acquired the infection in leprosy endemic colonial possessions. Such alarmists clamoured for the adoption of vigorous leper segregation policies in such colonies. But the contagiousness of leprosy did not go unquestioned by other westerners. The convocation in Berlin of the first international meeting on leprosy revealed the interplay of differing and sometimes incompatible views about the containment of leprosy by segregation. The roles of officials from several countries, as well as the roles of five protagonists (Albert Ashmead, Jules Goldschmidt, Edvard Ehlers. Armauer Hansen, and Phineas Abraham) in the shaping of the Berlin Conference are here examined.
The first international leprosy conference, Berlin, 1897: the politics of segregation.
Pandya, Shubhada S
2003-01-01
The present paper examines the first attempts to internationalize the problem of leprosy, a subject hitherto overlooked by historians of imperialism and disease. The last decade of the nineteenth century saw many in the 'civilized countries' of the imperialist West gripped by a paranoia about an invasion of leprosy via germ-laden immigrants and returning expatriates who had acquired the infection in leprosy-endemic colonial possessions. Such alarmists clamoured for the adoption of vigorous leper segregation policies in such colonies. But the contagiousness of leprosy did not go unquestioned by other westerners. The convocation in Berlin of the first international meeting on leprosy revealed the interplay of differing and sometimes incompatible views about the containment of leprosy by segregation. The roles of officials from several countries, as well as the roles of five protagonists (Albert Ashmead, Jules Goldschmidt, Edvard Ehlers, Armauer Hansen, and Phineas Abraham) in the shaping of the Berlin Conference are here examined.
Morais, Fábio Barreto
2018-04-01
The Nobel Prize is the world's foremost honor for scientific advances in medicine and other areas. Founded by Alfred Nobel, the prizes have been awarded annually since 1901. We reviewed the literature on persons who have won or competed for this prize in subjects related to vision and ophthalmology. The topics were divided into vision physiology, diagnostic and therapeutic methods, disease mechanism, and miscellaneous categories. Allvar Gullstrand is the only ophthalmologist to win a Nobel Prize; he is also the only one to receive it for work in ophthalmology. Other ophthalmologists that have been nominated were Hjalmar Schiötz (tonometer), Karl Koller (topical anesthesia), and Jules Gonin (retinal detachment). Other scientists have won the prize for eye-related research: Ragnar Granit, Haldan Hartline and George Wald (chemistry and physiology of vision), and David Hubel and Torsten Wiesel (processing in the visual system). Peter Medawar is the only person born in Brazil to have won the Nobel Prize.
Barthes, N; Boudsocq, J-P
2017-06-01
In the summer of 2015, soldiers of the 3rd Foreign Infantry Regiment and civilian scientists mounted a joint expedition on foot to reconnoiter and better define the southern frontier of French Guiana with Brazil. Three doctor-nurse pairs worked in relay to provide medical support for this unprecedented 42-day, 320-km journey through a hostile and isolated environment, a mission whose success was made possible by large-scale logistic and technical prowess. The army health department, using knowledge gained from previous large-scale missions and expeditions and from its staff's local experience, provided its technical support for personnel selection, organization of the health logistics, and field support. This article describes the difficulties encountered from a medical perspective, the diseases encountered, and the final assessments of the personnel who completed this expedition.
On multi-level thinking and scientific understanding
NASA Astrophysics Data System (ADS)
McIntyre, Michael Edgeworth
2017-10-01
Professor Duzheng YE's name has been familiar to me ever since my postdoctoral years at MIT with Professors Jule CHARNEY and Norman PHILLIPS, back in the late 1960s. I had the enormous pleasure of meeting Professor YE personally in 1992 in Beijing. His concern to promote the very best science and to use it well, and his thinking on multi-level orderly human activities, reminds me not only of the communication skills we need as scientists but also of the multi-level nature of science itself. Here I want to say something (a) about what science is; (b) about why multi-level thinking—and taking more than one viewpoint—is so important for scientific as well as for other forms of understanding; and (c) about what is meant, at a deep level, by "scientific understanding" and trying to communicate it, not only with lay persons but also across professional disciplines. I hope that Professor YE would approve.
A multiple scales approach to maximal superintegrability
NASA Astrophysics Data System (ADS)
Gubbiotti, G.; Latini, D.
2018-07-01
In this paper we present a simple, algorithmic test to establish if a Hamiltonian system is maximally superintegrable or not. This test is based on a very simple corollary of a theorem due to Nekhoroshev and on a perturbative technique called the multiple scales method. If the outcome is positive, this test can be used to suggest maximal superintegrability, whereas when the outcome is negative it can be used to disprove it. This method can be regarded as a finite dimensional analog of the multiple scales method as a way to produce soliton equations. We use this technique to show that the real counterpart of a mechanical system found by Jules Drach in 1935 is, in general, not maximally superintegrable. We give some hints on how this approach could be applied to classify maximally superintegrable systems by presenting a direct proof of the well-known Bertrand’s theorem.
NASA Astrophysics Data System (ADS)
Thurner, Martin; Beer, Christian; Carvalhais, Nuno; Forkel, Matthias; Tito Rademacher, Tim; Santoro, Maurizio; Tum, Markus; Schmullius, Christiane
2016-04-01
Long-term vegetation dynamics are one of the key uncertainties of the carbon cycle. There are large differences in simulated vegetation carbon stocks and fluxes including productivity, respiration and carbon turnover between global vegetation models. Especially the implementation of climate-related mortality processes, for instance drought, fire, frost or insect effects, is often lacking or insufficient in current models and their importance at global scale is highly uncertain. These shortcomings have been due to the lack of spatially extensive information on vegetation carbon stocks, which cannot be provided by inventory data alone. Instead, we recently have been able to estimate northern boreal and temperate forest carbon stocks based on radar remote sensing data. Our spatially explicit product (0.01° resolution) shows strong agreement to inventory-based estimates at a regional scale and allows for a spatial evaluation of carbon stocks and dynamics simulated by global vegetation models. By combining this state-of-the-art biomass product and NPP datasets originating from remote sensing, we are able to study the relation between carbon turnover rate and a set of climate indices in northern boreal and temperate forests along spatial gradients. We observe an increasing turnover rate with colder winter temperatures and longer winters in boreal forests, suggesting frost damage and the trade-off between frost adaptation and growth being important mortality processes in this ecosystem. In contrast, turnover rate increases with climatic conditions favouring drought and insect outbreaks in temperate forests. Investigated global vegetation models from the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP), including HYBRID4, JeDi, JULES, LPJml, ORCHIDEE, SDGVM, and VISIT, are able to reproduce observation-based spatial climate - turnover rate relationships only to a limited extent. While most of the models compare relatively well in terms of NPP, simulated vegetation carbon stocks are severely biased compared to our biomass dataset. Current limitations lead to considerable uncertainties in the estimated vegetation carbon turnover, contributing substantially to the forest feedback to climate change. Our results are the basis for improving mortality concepts in models and estimating their impact on the land carbon balance.
NASA Astrophysics Data System (ADS)
Kruijt, B.; Jans, W.; Vasconcelos, S.; Tribuzy, E. S.; Felsemburgh, C.; Eliane, M.; Rowland, L.; da Costa, A. C. L.; Meir, P.
2014-12-01
In many dynamic vegetation models, degradation of the tropical forests is induced because they assume that productivity falls rapidly when temperatures rise in the region of 30-40°C. Apart plant respiration, this is due to the assumptions on the temperature optima of photosynthetic capacity, which are low and can differ widely between models, where in fact hardly any empirical information is available for tropical forests. Even less is known about the possibility that photosynthesis will acclimate to changing temperatures. The objective of this study to is to provide better estimates for optima, as well as to determine whether any acclimation to temperature change is to be expected. We present both new and hitherto unpublished data on the temperature response of photosynthesis of Amazon rainforest trees, encompassing three sites, several species and five field campaigns. Leaf photosynthesis and its parameters were determined at a range of temperatures. To study the long-term (seasonal) acclimation of this response, this was combined with an artificial, in situ, multi-season leaf heating experiment. The data show that, on average for all non-heated cases, the photosynthetic parameter Vcmax weakly peaks between 35 and 40 ˚C, while heating does not have a clearly significant effect. Results for Jmax are slightly different, with sharper peaks. Scatter was relatively high, which could indicate weak overall temperature dependence. The combined results were used to fit new parameters to the various temperature response curve functions in a range of DGVMs. The figure shows a typical example: while the default Jules model assumes a temperature optimum for Vcmax at around 33 ˚C, the data suggest that Vcmax keeps rising up to at least 40 ˚C. Of course, calculated photosynthesis, obtained by applying this Vcmax in the Farquhar model, peaks at lower temperature. Finally, the implication of these new model parameters for modelled climate change impact on modelled Amazon forests will be assessed, where it is expected that predicted die-back will be less.
NASA Astrophysics Data System (ADS)
Rowland, L.; Harper, A.; Christoffersen, B. O.; Galbraith, D. R.; Imbuzeiro, H. M. A.; Powell, T. L.; Doughty, C.; Levine, N. M.; Malhi, Y.; Saleska, S. R.; Moorcroft, P. R.; Meir, P.; Williams, M.
2015-04-01
Accurately predicting the response of Amazonia to climate change is important for predicting climate change across the globe. Changes in multiple climatic factors simultaneously result in complex non-linear ecosystem responses, which are difficult to predict using vegetation models. Using leaf- and canopy-scale observations, this study evaluated the capability of five vegetation models (Community Land Model version 3.5 coupled to the Dynamic Global Vegetation model - CLM3.5-DGVM; Ecosystem Demography model version 2 - ED2; the Joint UK Land Environment Simulator version 2.1 - JULES; Simple Biosphere model version 3 - SiB3; and the soil-plant-atmosphere model - SPA) to simulate the responses of leaf- and canopy-scale productivity to changes in temperature and drought in an Amazonian forest. The models did not agree as to whether gross primary productivity (GPP) was more sensitive to changes in temperature or precipitation, but all the models were consistent with the prediction that GPP would be higher if tropical forests were 5 °C cooler than current ambient temperatures. There was greater model-data consistency in the response of net ecosystem exchange (NEE) to changes in temperature than in the response to temperature by net photosynthesis (An), stomatal conductance (gs) and leaf area index (LAI). Modelled canopy-scale fluxes are calculated by scaling leaf-scale fluxes using LAI. At the leaf-scale, the models did not agree on the temperature or magnitude of the optimum points of An, Vcmax or gs, and model variation in these parameters was compensated for by variations in the absolute magnitude of simulated LAI and how it altered with temperature. Across the models, there was, however, consistency in two leaf-scale responses: (1) change in An with temperature was more closely linked to stomatal behaviour than biochemical processes; and (2) intrinsic water use efficiency (IWUE) increased with temperature, especially when combined with drought. These results suggest that even up to fairly extreme temperature increases from ambient levels (+6 °C), simulated photosynthesis becomes increasingly sensitive to gs and remains less sensitive to biochemical changes. To improve the reliability of simulations of the response of Amazonian rainforest to climate change, the mechanistic underpinnings of vegetation models need to be validated at both leaf- and canopy-scales to improve accuracy and consistency in the quantification of processes within and across an ecosystem.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rafique, Rashid; Zhao, Fang; de Jong, Rogier
The net primary productivity (NPP) is commonly used for understanding the dynamics of terrestrial ecosystems and their role in carbon cycle. We used a combination of the most recent NDVI and model–based NPP estimates (from five models of the TRENDY project) for the period 1982-2012, to study the role of terrestrial ecosystems in carbon cycle under the prevailing climate conditions. We found that 80% and 67% of the global land area showed positive NPP and NDVI values, respectively, for this period. The global NPP was estimated to be about 63 Pg C y -1, with an increase of 0.214 Pgmore » C y -1 y -1. Similarly, the global mean NDVI was estimated to be 0.33, with an increasing trend of 0.00041 y-1. The spatial patterns of NPP and NDVI demonstrated substantial variability, especially at the regional level, for most part of the globe. However, on temporal scale, both global NPP and NDVI showed a corresponding pattern of increase (decrease) for the duration of this study except for few years (e.g. 1990 and 1995-98). Generally, the Northern Hemisphere showed stronger NDVI and NPP increasing trends over time compared to the Southern Hemisphere; however, NDVI showed larger trends in Temperate regions while NPP showed larger trends in Boreal regions. Among the five models, the maximum and minimum NPP were produced by JULES (72.4 Pg C y -1) and LPJ (53.72 Pg C y -1) models, respectively. At latitudinal level, the NDVI and NPP ranges were ~0.035 y -1 to ~-0.016 y -1 and ~0.10 Pg C y -1 y -1 to ~-0.047 Pg C y -1 y -1, respectively. Overall, the results of this study suggest that the modeled NPP generally correspond to the NDVI trends in the temporal dimension. Lastly, the significant variability in spatial patterns of NPP and NDVI trends points to a need for research to understand the causes of these discrepancies between molded and observed ecosystem dynamics, and the carbon cycle.« less
NASA Astrophysics Data System (ADS)
Churkina, G.; Zaehle, S.; Hughes, J.; Viovy, N.; Chen, Y.; Jung, M.; Heumann, B. W.; Ramankutty, N.; Heimann, M.; Jones, C.
2010-09-01
European ecosystems are thought to take up large amounts of carbon, but neither the rate nor the contributions of the underlying processes are well known. In the second half of the 20th century, carbon dioxide concentrations have risen by more that 100 ppm, atmospheric nitrogen deposition has more than doubled, and European mean temperatures were increasing by 0.02 °C yr-1. The extents of forest and grasslands have increased with the respective rates of 5800 km2 yr-1 and 1100 km2 yr-1 as agricultural land has been abandoned at a rate of 7000 km2 yr-1. In this study, we analyze the responses of European land ecosystems to the aforementioned environmental changes using results from four process-based ecosystem models: BIOME-BGC, JULES, ORCHIDEE, and O-CN. The models suggest that European ecosystems sequester carbon at a rate of 56 TgC yr-1 (mean of four models for 1951-2000) with strong interannual variability (±88 TgC yr-1, average across models) and substantial inter-model uncertainty (±39 TgC yr-1). Decadal budgets suggest that there has been a continuous increase in the mean net carbon storage of ecosystems from 85 TgC yr-1 in 1980s to 108 TgC yr-1 in 1990s, and to 114 TgC yr-1 in 2000-2007. The physiological effect of rising CO2 in combination with nitrogen deposition and forest re-growth have been identified as the important explanatory factors for this net carbon storage. Changes in the growth of woody vegetation are suggested as an important contributor to the European carbon sink. Simulated ecosystem responses were more consistent for the two models accounting for terrestrial carbon-nitrogen dynamics than for the two models which only accounted for carbon cycling and the effects of land cover change. Studies of the interactions of carbon-nitrogen dynamics with land use changes are needed to further improve the quantitative understanding of the driving forces of the European land carbon balance.
Zhang, Lijun; Sy, Mary Ellen; Mai, Harry; Yu, Fei; Hamilton, D Rex
2015-01-01
To compare the prediction error after toric intraocular lens (IOL) (Acrysof IQ) implantation using corneal astigmatism measurements obtained with an IOLMaster automated keratometer and a Galilei dual rotating camera Scheimpflug-Placido tomographer. Jules Stein Eye Institute, University of California Los Angeles, Los Angeles, California, USA. Retrospective case series. The predicted residual astigmatism after toric IOL implantation was calculated using preoperative astigmatism values from an automated keratometer and the total corneal power (TCP) determined by ray tracing through the measured anterior and posterior corneal surfaces using dual Scheimpflug-Placido tomography. The prediction error was calculated as the difference between the predicted astigmatism and the manifest astigmatism at least 1 month postoperatively. The calculations included vector analysis. The study evaluated 35 eyes (35 patients). The preoperative corneal posterior astigmatism mean magnitude was 0.33 diopter (D) ± 0.16 (SD) (vector mean 0.23 × 176). Twenty-six eyes (74.3%) had with-the-rule (WTR) posterior astigmatism. The postoperative manifest refractive astigmatism mean magnitude was 0.38 ± 0.18 D (vector mean 0.26 × 171). There was no statistically significant difference in the mean magnitude prediction error between the automated keratometer and TCP techniques. However, the automated keratometer method tended to overcorrect WTR astigmatism and undercorrect against-the-rule (ATR) astigmatism. The TCP technique lacked these biases. The automated keratometer and TCP methods for estimating the magnitude of corneal astigmatism gave similar results. However, the automated keratometer method tended to overcorrect WTR astigmatism and undercorrect ATR astigmatism. Dr. Hamilton has received honoraria for educational lectures from Ziemer Ophthalmic Systems. No other author has a financial or proprietary interest in any material or method mentioned. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.
Booth, Valerie; Warschawski, Dror E; Santisteban, Nury P; Laadhari, Marwa; Marcotte, Isabelle
2017-11-01
Discoveries relating to innate immunity and antimicrobial peptides (AMPs) granted Bruce Beutler and Jules Hoffmann a Nobel prize in medicine in 2011, and opened up new avenues for the development of therapies against infections, and even cancers. The mechanisms by which AMPs interact with, and ultimately disrupt, bacterial cell membranes is still, to a large extent, incompletely understood. Up until recently, this mechanism was studied using model lipid membranes that failed to reproduce the complexity of molecular interactions present in real cells comprising lipids but also membrane proteins, a cell wall containing peptidoglycan or lipopolysaccharides, and other molecules. In this review, we focus on recent attempts to study, at the molecular level, the interaction between cationic AMPs and intact bacteria, by 2 H solid-state NMR. Specifically-labeled lipids allow us to focus on the interaction of AMPs with the heart of the bacterial membrane, and measure the lipid order and its variation upon interaction with various peptides. We will review the important parameters to consider in such a study, and summarize the results obtained in the past 5years on various peptides, in particular aurein 1.2, caerin 1.1, MSI-78 and CA(1-8)M(1-10). This article is part of a Special Issue entitled: Biophysics in Canada, edited by Lewis Kay, John Baenziger, Albert Berghuis and Peter Tieleman. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Black, E.; Vidale, P. L.; Verhoef, A.; Cuadro, S. V.
2012-04-01
Over the next decades increasing oil and carbon prices will lead to a proliferation of energy crop cultivation initiatives. Many of these will be based in developing countries, and hence will affect some of the poorest people in the world. The capacity of such initiatives to alleviate poverty in the long term depends on their environmental sustainability. Specifically, the exploitation of water resources in an unsustainable manner may permanently damage vulnerable ecosystems and ultimately deepen poverty. These issues have motivated a collaborative project - Integrated Carbon, Water and Land Management for Poverty Alleviation (ICWALPA), which asks whether the export of bio-fuel technology from Brazil to Ghana will alleviate poverty. This presentation will describe the initial results from ICWALPA - including the development of an integrated environmental modelling framework and its application to sugarcane cultivation under scenarios of climate change. The environmental model used to represent the biophysical interactions is process-based and implemented in the framework of the Joint UK Land Environment Simulator (JULES). Crop growth is predicted dynamically by accumulating the carbon assimilated during photosynthesis and is then allocated according to well-established allometric principles. Two contrasting case studies will be presented: the Sao Paulo region of Brazil (where there is an established sugarcane industry) and the Daka River region of Ghana (where commercial sugarcane cultivation is planned). We show that our model is capable of reproducing both the spatial and temporal variability in sugarcane yield for the Sao Paulo province of Brazil - lending credence to the projections for Ghana. For Ghana, we show that, providing there is sufficient irrigation, it is possible to generate approximately 75% of the yield achieved in the Sao Paulo province. In the final part of the study, the behaviour of sugarcane under an idealized climate change scenario is explored. It is shown that the increased drought tolerance that results from higher CO2 concentrations mitigates the greater water stress associated with higher evaporation.
NASA Astrophysics Data System (ADS)
Moorcroft, P. R.; Zhang, K.; Castanho, A. D. D. A.; Galbraith, D.; Moghim, S.; Levine, N. M.; Bras, R. L.; Coe, M. T.; Costa, M. H.; Malhi, Y.; Longo, M.; Knox, R. G.; McKnight, S. L.; Wang, J.
2014-12-01
There is considerable interest and uncertainty regarding the expected fate of the Amazon over the coming century in face of the combined impacts of climate change, rising atmospheric CO2 levels, and on-going land transformation in the region. In this analysis, we explore the fate of Amazonian ecosystems under projected climate, CO2 and land-use change in the 21st century using three state-of-the-art terrestrial biosphere models (ED2, IBIS, and JULES) driven by three representative, bias-corrected GCM climate projections (PCM1, CCSM3, and HadCM3) under the SRES A2 scenario, coupled with two land-use change scenarios. We assess the relative roles of climate change, CO2 fertilization, land-use change, and fire in driving the projected changes in Amazonian biomass and forest extent. Our results indicate that the impacts of climate change depend strongly on the direction and severity of projected changes in precipitation regimes within the region: under the driest climate projection, climate change alone is predicted to reduce Amazonian forest cover by an average of 14%; however, the models predict that CO2 fertilization will enhance vegetation productivity and alleviate climate-induced increases in plant water stress, and as a result sustain high biomass forests, even under the driest climate scenario. Land-use change and changes in fire frequency are predicted cause additional aboveground live biomass loss and changes in forest extent. The relative impact of land-use and fire dynamics versus the impacts of climate and CO2 on the Amazon varies considerably, depending on both the climate and land-use scenarios used and on the terrestrial biosphere model, highlighting the importance of improved understanding of all four factors -- future climate, CO2 fertilization effects, fire and land-use -- to the fate of the Amazon over the coming century.
The International Space Station and the Space Debris Environment: 10 Years On
NASA Technical Reports Server (NTRS)
Johnson, Nicholas; Klinkrad, Heiner
2009-01-01
For just over a decade the International Space Station (ISS), the most heavily protected vehicle in Earth orbit, has weathered the space debris environment well. Numerous hypervelocity impact features on the surface of ISS caused by small orbital debris and meteoroids have been observed. In addition to typical impacts seen on the large solar arrays, craters have been discovered on windows, hand rails, thermal blankets, radiators, and even a visiting logistics module. None of these impacts have resulted in any degradation of the operation or mission of the ISS. Validating the rate of small particle impacts on the ISS as predicted by space debris environment models is extremely complex. First, the ISS has been an evolving structure, from its original 20 metric tons to nearly 300 metric tons (excluding logistics vehicles) ten years later. Hence, the anticipated space debris impact rate has grown with the increasing size of ISS. Secondly, a comprehensive visual or photographic examination of the complete exterior of ISS has never been accomplished. In fact, most impact features have been discovered serendipitously. Further complications include the estimation of the size of an impacting particle without knowing its mass, velocity, and angle of impact and the effect of shadowing by some ISS components. Inadvertently and deliberately, the ISS has also been the source of space debris. The U.S. Space Surveillance Network officially cataloged 65 debris from ISS from November 1998 to November 2008: from lost cameras, sockets, and tool bags to intentionally discarded equipment and an old space suit. Fortunately, the majority of these objects fall back to Earth quickly with an average orbital lifetime of less than two months and a maximum orbital lifetime of a little more than 15 months. The cumulative total number of debris object-years is almost exactly 10, the equivalent of one piece of debris remaining in orbit for 10 years. An unknown number of debris too small to be tracked and cataloged have also been generated, but normally with even shorter orbital lifetimes. Finally, eight collision avoidance maneuvers have been performed to avoid potential collisions between ISS and large, tracked space debris. The most recent such maneuver was accomplished by ESA's Automated Transfer Vehicle, the Jules Verne, just three months before the 10th anniversary of the launch of ISS's first element.
Rafique, Rashid; Zhao, Fang; de Jong, Rogier; ...
2016-02-25
The net primary productivity (NPP) is commonly used for understanding the dynamics of terrestrial ecosystems and their role in carbon cycle. We used a combination of the most recent NDVI and model–based NPP estimates (from five models of the TRENDY project) for the period 1982-2012, to study the role of terrestrial ecosystems in carbon cycle under the prevailing climate conditions. We found that 80% and 67% of the global land area showed positive NPP and NDVI values, respectively, for this period. The global NPP was estimated to be about 63 Pg C y -1, with an increase of 0.214 Pgmore » C y -1 y -1. Similarly, the global mean NDVI was estimated to be 0.33, with an increasing trend of 0.00041 y-1. The spatial patterns of NPP and NDVI demonstrated substantial variability, especially at the regional level, for most part of the globe. However, on temporal scale, both global NPP and NDVI showed a corresponding pattern of increase (decrease) for the duration of this study except for few years (e.g. 1990 and 1995-98). Generally, the Northern Hemisphere showed stronger NDVI and NPP increasing trends over time compared to the Southern Hemisphere; however, NDVI showed larger trends in Temperate regions while NPP showed larger trends in Boreal regions. Among the five models, the maximum and minimum NPP were produced by JULES (72.4 Pg C y -1) and LPJ (53.72 Pg C y -1) models, respectively. At latitudinal level, the NDVI and NPP ranges were ~0.035 y -1 to ~-0.016 y -1 and ~0.10 Pg C y -1 y -1 to ~-0.047 Pg C y -1 y -1, respectively. Overall, the results of this study suggest that the modeled NPP generally correspond to the NDVI trends in the temporal dimension. Lastly, the significant variability in spatial patterns of NPP and NDVI trends points to a need for research to understand the causes of these discrepancies between molded and observed ecosystem dynamics, and the carbon cycle.« less
Holz, Frank G; Steinberg, Julia S; Göbel, Arno; Fleckenstein, Monika; Schmitz-Valckenberg, Steffen
2015-01-01
Fundus autofluorescence (FAF) imaging allows for topographic mapping of intrisnic fluorophores in the retinal pigment epithelial cell monolayer, as well as mapping of other fluorophores that may occur with disease in the outer retina and the sub-neurosensory space. FAF imaging provides information not obtainable with other imaging modalities. Near-infrared fundus autofluorescence images can also be obtained in vivo, and may be largely melanin-derived. FAF imaging has been shown to be useful in a wide spectrum of macular and retinal diseases. The scope of applications now includes identification of diseased RPE in macular/retinal diseases, elucidating pathophysiological mechanisms, identification of early disease stages, refined phenotyping, identification of prognostic markers for disease progression, monitoring disease progression in the context of both natural history and interventional therapeutic studies, and objective assessment of luteal pigment distribution and density as well as RPE melanin distribution. Here, we review the use of FAF imaging in various phenotypic manifestations of dry AMD.
NASA Astrophysics Data System (ADS)
Lyuksyutov, Sergei F.; Paramonov, Pavel B.; Sigalov, Grigori; Vaia, Richard A.; Juhl, Shane; Sancaktar, Erol
2003-10-01
The combination of localized softening attolitres (10^2 -10^4) of polymer film by Jule heating, extremely non-uniform electric field gradients to polarize and manipulate the soften polymer, and single step technique using conventional atomic force microscopy (AFM), establishes a new paradigm for nanolithography in a broad class of polymer materials allowing rapid (order of milliseconds) creation of raised and depressed nanostructures without external heating of a polymer film of AFM tip-film contact [1]. In this work we present recent studies of AFM-assisted electrostatic nanolithography (AFMEN) such as amplitude-modulated AFMEN, and the humidity influence on nanostructures formation during contact mode AFMEN. It has been shown that the aspect ratio of nanostructures grows on the order of magnitude (0.2), while the lateral dimensions of nanodots decreases down to 10-15 nm. [1] S.F. Lyuksyutov, R.A. Vaia, P.B. Paramonov, S. Juhl, L. Waterhouse, R.M. Ralich, G. Sigalov, and E. Sancaktar, "Electrostatic nanolithography in polymers using atomic force microscopy," Nature Materials 2, 468-472 (2003)
Contested Waterlines: The Wave-Line Theory and Shipbuilding in the Nineteenth Century.
Ferreiro, Larrie D; Pollara, Alexander
2016-04-01
Ship hydrodynamics in the nineteenth century was dominated by John Scott Russell's wave-line theory. Russell, a prominent British shipbuilder and scientist, argued that wavemaking was the primary source of resistance for ships, and that by designing ships according to trigonometric curves and proportions (the wave line) this resistance could effectively be eliminated. From the 1840s to the 1880s, shipbuilders such as John Willis Griffiths, Donald McKay and George Steers designed their clipper ships (like Sea Witch and Flying Cloud) and yachts (America) with wave-line hulls, while authors like Jules Verne referenced Russell's theory. The wave line slowly faded after William Froude developed his laws of ship resistance. The article examines how Russell's theory became accepted by technical experts and the wider public to become the most widely known ship hydrodynamic theory of the 1800s-a reminder of how a persuasive idea can take hold of an entire profession, and even the public, for a long time.
Publications on Peripheral Nerve Injuries during World War I: A Dramatic Increase in Knowledge.
Koehler, Peter J
2016-01-01
Publications from French (Jules Tinel and Chiriachitza Athanassio-Bénisty), English (James Purves-Stewart, Arthur Henry Evans and Hartley Sidney Carter), German (Otfrid Foerster and Hermann Oppenheim) and American (Charles Harrison Frazier and Byron Stookey) physicians from both sides of the front during World War I (WWI) contributed to a dramatic increase in knowledge about peripheral nerve injuries. Silas Weir Mitchell's original experience with respect to these injuries, and particularly causalgia, during the American Civil War was further expanded in Europe during WWI. Following the translation of one of his books, he was referred to mainly by French physicians. During WWI, several French books were in turn translated into English, which influenced American physicians, as was observed in the case of Byron Stookey. The establishment of neurological centres played an important role in the concentration of experience and knowledge. Several eponyms originated during this period (including the Hoffmann-Tinel sign and the Froment sign). Electrodiagnostic tools were increasingly used. © 2016 S. Karger AG, Basel.
Plant Nitrogen Uptake in Terrestrial Biogeochemical Models
NASA Astrophysics Data System (ADS)
Marti Donati, A.; Cox, P.; Smith, M. J.; Purves, D.; Sitch, S.; Jones, C. D.
2013-12-01
Most terrestrial biogeochemical models featured in the last Intergovernmental Panel on Climate Change (IPPC) Assessment Report highlight the importance of the terrestrial Carbon sequestration and feedbacks between the terrestrial Carbon cycle and the climate system. However, these models have been criticized for overestimating predicted Carbon sequestration and its potential climate feedback when calculating the rate of future climate change because they do not account for the Carbon sequestration constraints caused by nutrient limitation, particularly Nitrogen (N). This is particularly relevant considering the existence of a substantial deficit of Nitrogen for plants in most areas of the world. To date, most climate models assume that plants have access to as much Nitrogen as needed, but ignore the nutrient requirements for new vegetation growth. Determining the natural demand and acquisition for Nitrogen and its associated resource optimization is key when accounting for the Carbon sequestration constrains caused by nutrient limitation. The few climate models that include C-N dynamics have illustrated that the stimulation of plant growth over the coming century may be significantly smaller than previously predicted. However, models exhibit wide differences in their predictive accuracy and lead to widely diverging and inconsistent projections accounting for an uncertain Carbon sequestration decrease due to Nitrogen limitation ranging from 7 to 64%. This reduction in growth is partially offset by an increase in the availability of nutrients resulting from an accelerated rate of decomposition of dead plants and other organic matter that occurring with a rise in temperature. However, this offset does not counterbalance the reduced level of plant growth calculated by natural nutrient limitations. Additionally, Nitrogen limitation is also expected to become more pronounced in some ecosystems as atmospheric CO2 concentration increases; resulting in less new growth and higher atmospheric CO2 concentrations than originally expected. This study compares the differences in the predictions of alternative models of plant N uptake found in different terrestrial biogeochemical models with the predictions from a new N-uptake model developed under the Joint UK Land Environment Simulator (JULES) framework. We implement a methodology for the construction, parameterization and evaluation of N uptake models to fully decompose all the N uptake component processes in terms of their parameter uncertainty and the accuracy of their predictions with respect to different empirical data sets. Acknowledgements This work has been funded by the European Commission FP7-PEOPLE-ITN-2008 Marie Curie Action: "Greencycles II: FP7-PEOPLE-ITN-2008 Marie Curie Action: "Networks for Initial Training"
[A quarantine of plague at the lazaret of Frioul in 1901].
Chevallier, Jacques
2015-01-01
In September 1901, a cruise for work and pleasure is organized in Mediterranean including VIP all firstclass (politicals, scientists, clergymen...) These were 174 passengers on the ship Senegal. After a departure from Marseille, the ship must quickly turn and go back on account of a sailor in the crew might be sicked with plague. A quarantine was organised in the lazaret of Frioul's island. This man died but an another actually ill will be cured. All the conference participents landed in the Frioul lazaret stayed only seven days on place and remained uninjured. This misadventure will be studied by scientific people and given to authorities. So, Pr Jules Buckoy' communication to the french Academy of medicine. Adrien Proust gave a report. In this doctoral thesis in 1902 Joseph Pellissier reported all the cases of plague cured in the Frioul lazaret. The physician Charles Leroux made an epidemiologic study about effects and troubles with plague serums. A lot of orig- inal and beautiful photographs, notably those by the famous passenger, Léon Gaumont, are joined in our presentation.
ECG-cryptography and authentication in body area networks.
Zhang, Zhaoyang; Wang, Honggang; Vasilakos, Athanasios V; Fang, Hua
2012-11-01
Wireless body area networks (BANs) have drawn much attention from research community and industry in recent years. Multimedia healthcare services provided by BANs can be available to anyone, anywhere, and anytime seamlessly. A critical issue in BANs is how to preserve the integrity and privacy of a person's medical data over wireless environments in a resource efficient manner. This paper presents a novel key agreement scheme that allows neighboring nodes in BANs to share a common key generated by electrocardiogram (ECG) signals. The improved Jules Sudan (IJS) algorithm is proposed to set up the key agreement for the message authentication. The proposed ECG-IJS key agreement can secure data communications over BANs in a plug-n-play manner without any key distribution overheads. Both the simulation and experimental results are presented, which demonstrate that the proposed ECG-IJS scheme can achieve better security performance in terms of serval performance metrics such as false acceptance rate (FAR) and false rejection rate (FRR) than other existing approaches. In addition, the power consumption analysis also shows that the proposed ECG-IJS scheme can achieve energy efficiency for BANs.
Early Astronomical Sequential Photography, 1873-1923
NASA Astrophysics Data System (ADS)
Bonifácio, Vitor
2011-11-01
In 1873 Jules Janssen conceived the first automatic sequential photographic apparatus to observe the eagerly anticipated 1874 transit of Venus. This device, the 'photographic revolver', is commonly considered today as the earliest cinema precursor. In the following years, in order to study the variability or the motion of celestial objects, several instruments, either manually or automatically actuated, were devised to obtain as many photographs as possible of astronomical events in a short time interval. In this paper we strive to identify from the available documents the attempts made between 1873 and 1923, and discuss the motivations behind them and the results obtained. During the time period studied astronomical sequential photography was employed to determine the time of the instants of contact in transits and occultations, and to study total solar eclipses. The technique was seldom used but apparently the modern film camera invention played no role on this situation. Astronomical sequential photographs were obtained both before and after 1895. We conclude that the development of astronomical sequential photography was constrained by the reduced number of subjects to which the technique could be applied.
A doctoral thesis about Carol Davila written in Paris in 1936.
Rogozea, Liliana; Dumitrascu, Dinu I; Triff, Dorin; Leasu, Florin; Dumitraşcu, Dan L
2014-01-01
Carol Davila, the father of the Romanian modern medicine, made decisive contributions to the development of health sciences in the Romanian Principalities in the last decades of the nineteenth century. The merit of his scientific work was recognized beyond the borders of his country. His life (not devoid of anecdotic instances and unknown episodes) and especially his work have aroused considerable interest among numerous medical historians. This paper presents a historical study elaborated in France, but until recently ignored, dedicated to the biography of Carol Davila. It concerns the medical doctoral thesis (State Diploma) elaborated by Joseph Adler (born 1910 in Botoşani, Romania) under the supervision of professor Maxime Laignel-Lavastine, whose interest in Romania is well-known. Professor Laignel-Lavastine held the office of Secretary General of the International Society of History of Medicine (ISHM), founded in 1921, (replaced in this position by another French professor with links to Romania: Jules Guiart). The thesis comprises 48 pages and an exhaustive bibliography. It represents a token of the appreciation given to Davila's achievements by Europe's medical community.
A doctoral thesis about Carol Davila written in Paris in 1936
ROGOZEA, LILIANA; DUMITRASCU, DINU I.; TRIFF, DORIN; LEASU, FLORIN; DUMITRAŞCU, DAN L.
2014-01-01
Carol Davila, the father of the Romanian modern medicine, made decisive contributions to the development of health sciences in the Romanian Principalities in the last decades of the nineteenth century. The merit of his scientific work was recognized beyond the borders of his country. His life (not devoid of anecdotic instances and unknown episodes) and especially his work have aroused considerable interest among numerous medical historians. This paper presents a historical study elaborated in France, but until recently ignored, dedicated to the biography of Carol Davila. It concerns the medical doctoral thesis (State Diploma) elaborated by Joseph Adler (born 1910 in Botoşani, Romania) under the supervision of professor Maxime Laignel-Lavastine, whose interest in Romania is well-known. Professor Laignel-Lavastine held the office of Secretary General of the International Society of History of Medicine (ISHM), founded in 1921, (replaced in this position by another French professor with links to Romania: Jules Guiart). The thesis comprises 48 pages and an exhaustive bibliography. It represents a token of the appreciation given to Davila’s achievements by Europe’s medical community. PMID:26527997
Clarac, F; Barbara, J-G; Broussolle, E; Poirier, J
2012-01-01
We present a short historical review on the major institutions and figures that contributed to make Paris a renowned centre of physiology and neurology during the xixth and the first half of the xxth centuries. We purposely chose to focus on the period 1800-1950, as 1800 corresponds to the development of brain science and 1950 marks the true beginning of neuroscience. Our presentation is divided into four chapters, matching the main disciplines which have progressed and contributed the most to the knowledge we have of the brain sciences: anatomy, physiology, neurology, and psychiatry-psychology. The present article is the first of four parts of this review, which includes an introduction followed by the chapter on neuroanatomy and on anatomo-pathology, which includes biographical sketches of Félix Vicq d'Azyr, François-Xavier Bichat, Franz Joseph Gall, Jean Cruveilhier, Jules Bernard Luys, Paul Broca, Louis Ranvier, André-Victor Cornil, Albert Gombault, Jean Nageotte and René Couteaux. Copyright © 2011 Elsevier Masson SAS. All rights reserved.
NASA Astrophysics Data System (ADS)
Emanuel, K.
2015-12-01
Since the revolutionary work of Vilhelm Bjerknes, Jule Charney, and Eric Eady, geophysical fluid dynamics has dominated weather research and continues to play an important in climate dynamics. Although the physics of radiative transfer is central to understanding climate, it has played a far smaller role in weather research and is given only rudimentary attention in most educational programs in meteorology. Yet key contemporary problems in atmospheric science, such as the Madden-Julian Oscillation and the self-aggregation of moist convection, do not appear to have been solved by approaches based strictly on fluid dynamics and moist adiabatic thermodynamics. Here I will argue that many outstanding problems in meteorology and climate science involve a nontrivial coupling of circulation and radiation physics. In particular, the phenomenon of self-aggregation of moist convection depends on the interaction of radiation with time-varying water vapor and clouds, with strong implications for such diverse problems as the Madden-Julian Oscillation, tropical cyclones, and the relative insensitivity of tropical climate to radiative forcing. This argues for an augmentation of radiative transfer physics in graduate curricula in atmospheric sciences.
2013-06-27
CAPE CANAVERAL, Fla. – Inside the Operations and Checkout Building high bay at NASA’s Kennedy Space Center in Florida, members of the media receive an on activities in NASA’s Ground Systems Development and Operations, or GSDO, Program, Space Launch System and Orion crew module for Exploration Test Flight 1. Speaking to the media, from left are Scott Wilson, manager of Orion Production Operations at Kennedy Larry Price, Lockheed Martin deputy program manager for Orion Tom Erdman, from Marshall Space Flight Center’s Kennedy resident office Jules Schneider, Lockheed Martin manager of Orion Production Operations and Jeremy Parsons, chief of the GSDO Operations Integration Office at Kennedy. Orion is the exploration spacecraft designed to carry crews to space beyond low Earth orbit. It will provide emergency abort capability, sustain the crew during the space travel and provide safe re-entry from deep space return velocities. Orion’s first unpiloted test flight is scheduled to launch in 2014 atop a Delta IV rocket. A second uncrewed flight test is scheduled for 2017 on NASA’s Space Launch System rocket. For more information, visit http://www.nasa.gov/orion. Photo credit: NASA/Jim Grossmann
Desired machines: cinema and the world in its own image.
Canales, Jimena
2011-09-01
In 1895 when the Lumière brothers unveiled their cinematographic camera, many scientists were elated. Scientists hoped that the machine would fulfill a desire that had driven research for nearly half a century: that of capturing the world in its own image. But their elation was surprisingly short-lived, and many researchers quickly distanced themselves from the new medium. The cinematographic camera was soon split into two machines, one for recording and one for projecting, enabling it to further escape from the laboratory. The philosopher Henri Bergson joined scientists, such as Etienne-Jules Marey, who found problems with the new cinematographic order. Those who had worked to make the dream come true found that their efforts had been subverted. This essay focuses on the desire to build a cinematographic camera, with the purpose of elucidating how dreams and reality mix in the development of science and technology. It is about desired machines and their often unexpected results. The interplay between what "is" (the technical), what "ought" (the ethical), and what "could" be (the fantastical) drives scientific research.
A Selenological History of Lunar Poetics
NASA Astrophysics Data System (ADS)
von Chamier-Waite, C. T.
2016-01-01
The Moon. Centuries of human inquiry have engaged this mysterious object. The Moon embodies history, philosophy, cosmology, and passions; the nature of love, persecution, and our capacity for the sublime. This review considers a body of research on lunar poetics done for a series of artworks by the author. It will look at a few select writings that have profoundly influenced our epistemological, ontological, and poetic knowledge of the universe with the Moon as a central theme. Centered in the early seventeenth century at the time of Kepler and Galileo, this query follows the tendrils of lunar influences in both the sciences and literature that emanate from these two figures, forwards and backwards in time. Science, politics, theology, and the arts intertwine in this investigation. The works reviewed link the philosophy of Aristotle and the poetry of Lucian of Samosata to findings by Leonardo Da Vinci, Copernicus, Jules Verne, and others. The chosen philosophers have been selected because of their significant contributions to selenology and lunar poetics, and each of the figures reviewed have the honor of a namesake crater upon the Moon.
Permafrost thaw strongly reduces allowable CO2 emissions for 1.5°C and 2°C
NASA Astrophysics Data System (ADS)
Kechiar, M.; Gasser, T.; Kleinen, T.; Ciais, P.; Huang, Y.; Burke, E.; Obersteiner, M.
2017-12-01
We quantify how the inclusion of carbon emission from permafrost thaw impacts the budgets of allowable anthropogenic CO2 emissions. We use the compact Earth system model OSCAR v2.2 which we expand with a permafrost module calibrated to emulate the behavior of the complex models JSBACH, ORCHIDEE and JULES. When using the "exceedance" method and with permafrost thaw turned off, we find budgets very close to the CMIP5 models' estimates reported by IPCC. With permafrost thaw turned on, the total budgets are reduced by 3-4%. This corresponds to a 33-45% reduction of the remaining budget for 1.5°C, and a 9-13% reduction for 2°C. When using the "avoidance" method, however, permafrost thaw reduces the total budget by 3-7%, which corresponds to reductions by 33-56% and 56-79% of the remaining budget for 1.5°C and 2°C, respectively. The avoidance method relies on many scenarios that actually peak below the target whereas the exceedance method overlooks the carbon emitted by thawed permafrost after the temperature target is reached, which explains the difference. If we use only the subset of scenarios in which there is no net negative emissions, the permafrost-induced reduction in total budgets rises to 6-15%. Permafrost thaw therefore makes the emission budgets strongly path-dependent. We also estimate budgets of needed carbon capture in scenarios overshooting the temperature targets. Permafrost thaw strongly increases these capture budgets: in the case of a 1.5°C target overshot by 0.5°C, which is in line with the Paris agreement, about 30% more carbon must be captured. Our conclusions are threefold. First, inclusion of permafrost thaw systematically reduces the emission budgets, and very strongly so if the temperature target is overshot. Second, the exceedance method, that is the only one that complex models can follow, only partially accounts for the effect of slow non-linear processes such as permafrost thaw, leading to overestimated budgets. Third, the newfound strong path-dependency of the budgets renders the concept more delicate to use. For instance, using a budget that implicitly assumes a large development of negative emission technologies may lead to missing the target if these are not as scalable as anticipated.
Volcano art at Hawai`i Volcanoes National Park—A science perspective
Gaddis, Ben; Kauahikaua, James P.
2018-03-26
Long before landscape photography became common, artists sketched and painted scenes of faraway places for the masses. Throughout the 19th century, scientific expeditions to Hawaiʻi routinely employed artists to depict images for the people back home who had funded the exploration and for those with an interest in the newly discovered lands. In Hawaiʻi, artists portrayed the broad variety of people, plant and animal life, and landscapes, but a feature of singular interest was the volcanoes. Painters of early Hawaiian volcano landscapes created art that formed a cohesive body of work known as the “Volcano School” (Forbes, 1992). Jules Tavernier, Charles Furneaux, and D. Howard Hitchcock were probably the best known artists of this school, and their paintings can be found in galleries around the world. Their dramatic paintings were recognized as fine art but were also strong advertisements for tourists to visit Hawaiʻi. Many of these masterpieces are preserved in the Museum and Archive Collection of Hawaiʻi Volcanoes National Park, and in this report we have taken the opportunity to match the artwork with the approximate date and volcanological context of the scene.
Characterisation of wax works of art by gas chromatographic procedures.
Regert, M; Langlois, J; Colinart, S
2005-10-14
To identify the various natural and synthetic substances used by sculptors at the end of the 19th century, several contemporary reference samples were investigated by high temperature gas chromatography (HT GC) and HT GC-MS. Using specific chromatographic conditions and minimising sample preparation, we could separate, detect and identify a wide range of biomolecular markers covering a great variety of molecular weights and volatilities, with a minimum amount of sample, in a single run. Beeswax, spermaceti, carnauba, candellila and Japan waxes as well as pine resin derivatives, animal fats, paraffin, ozokerite and stearin, used as additives in wax works of art, were chemically investigated. In the case of low volatile compounds, transbutylation was performed. The structure of long-chain esters of spermaceti was elucidated for the first time by HT GC-MS analysis. Such a method was then carried out on 10 samples collected on a statuette of Junon by Antoine-Louis Barye (Louvre Museum, Paris, France) and on a sculpture by Aimé-Jules Dalou (Musée de la Révolution Française, Vizille, France). The analytical results obtained provide new data on the complex recipes elaborated by sculptors at the end of the 19th century.
Dieguez, Sebastian
2018-01-01
Cotard's syndrome is often described as the delusional belief that one is dead or non-existent. However, Jules Cotard's initial description (1880) of the "delusion of negations" was much richer and also involved delusions and claims of immortality and enormity, feelings of damnation, and illusions of bodily dissolution and transformation. Alternatively conceived as an extreme case of depression, hypochondria, or psychosis, the condition is considered rare and remains poorly understood. Cotard himself provided a taxonomy and several explanations for the condition, focusing on its distinction from classical persecutory delusions and suggesting that it could be a kind of reversed grandiosity. He proposed a psychosensory basis in the dissolution of mental imagery, which he then extended to a more general psychomotor impairment of volition. Other early authors highlighted a disorder of the bodily self, and more recent theories postulated an impairment of right hemispheric functions, leading to perceptual and somatosensory feelings of unreality, which coupled with reasoning impairments and an internalized attributional style led in turn to beliefs of non-existence. However, despite its striking presentation and its relevance to our understanding of self-awareness, Cotard's syndrome remains an elusive condition, rarely reported and poorly researched. © 2018 S. Karger AG, Basel.
International Systems Integration on the International Space Station
NASA Technical Reports Server (NTRS)
Gerstenmaier, William H.; Ticker, Ronald L.
2007-01-01
Over the next few months, the International Space Station (ISS), and human spaceflight in general, will undergo momentous change. The European Columbus and Japanese Kibo Laboratories will be added to the station joining U.S. and Russian elements already on orbit. Columbus, Jules Vernes Automated Transfer Vehicle (ATV) and Kibo Control Centers will soon be joining control centers in the US and Russia in coordinating ISS operations and research. The Canadian Special Purpose Dexterous Manipulator (SPDM) will be performing extra vehicular activities that previously only astronauts on EVA could do, but remotely and with increased safety. This paper will address the integration of these international elements and operations into the ISS, both from hardware and human perspectives. Interoperability of on-orbit systems and ground control centers and their human operators from Europe, Japan, Canada, Russia and the U.S. pose significant and unique challenges. Coordination of logistical support and transportation of crews and cargo is also a major challenge. As we venture out into the cosmos and inhabit the Moon and other planets, it's the systems and operational experience and partnership development on ISS, humanity's orbiting outpost that is making these journeys possible.
2013-06-27
CAPE CANAVERAL, Fla. – Inside the Operations and Checkout Building high bay at NASA’s Kennedy Space Center in Florida, members of the media receive an on activities in NASA’s Ground Systems Development and Operations, or GSDO, Program, Space Launch System and Orion crew module for Exploration Test Flight 1. Speaking to the media is Larry Price, Lockheed Martin deputy program manager for Orion. In the background, from left are Scott Wilson, manager of Orion Production Operations at Kennedy Jeremy Parsons, chief of the GSDO Operations Integration Office at Kennedy Tom Erdman, from Marshall Space Flight Center’s Kennedy resident office and Jules Schneider, Lockheed Martin manager of Orion Production Operations. Orion is the exploration spacecraft designed to carry crews to space beyond low Earth orbit. It will provide emergency abort capability, sustain the crew during the space travel and provide safe re-entry from deep space return velocities. Orion’s first unpiloted test flight is scheduled to launch in 2014 atop a Delta IV rocket. A second uncrewed flight test is scheduled for 2017 on NASA’s Space Launch System rocket. For more information, visit http://www.nasa.gov/orion. Photo credit: NASA/Jim Grossmann
Bruzzoniti, Maria Concetta; Kobylinska, Dorota Korte; Franko, Mladen; Sarzanini, Corrado
2010-04-14
A flow injection method has been developed for determination of silver. The method is based on a reduction reaction with sodium borohydride which leads to the formation of a colloidal species which is monitored at a wavelength of 390 nm. The reaction variables flow rate, sodium borohydride concentration and pH, which affect sensitivity, were investigated and their effects were established using a two-levels, three-factor experimental design. Further optimization of manifold variables (reaction coil and injection volume) allowed us to determine silver in the range 0.050-5.0 mg L(-1) with a minimum detectable concentration of 0.050 mg L(-1). Silver is added, as biocide, to drinking water for spacecrafts. The chemical species of silver, present in this kind of sample, were characterized by a procedure based on the selective retention of Ag(+) onto a 2.2.2. cryptand based substrate followed by determination of the non-bound and bound (after elution) Ag(+) by the FIA method. The method optimized was applied to a drinking water sample provided for the launch with the Automated Transfer Vehicle (ATV) module Jule Verne to the International Space Station (March 9, 2008). Copyright 2010 Elsevier B.V. All rights reserved.
The Arago Laboratory of Banyuls and some of its Academicians.
Soyer-Gobillard, Marie-Odile
2016-12-01
Since its founding in 1881 by Henri de Lacaze-Duthiers (1821-1901), the Arago Laboratory of Banyuls has been one of the three marine stations of the University Pierre and Marie Curie-Paris 6. It is located in Banyuls (Banyuls-sur-Mer) in Northern Catalonia. The center hosts researchers and students from all over the world. Some became famous, including four Nobel Prize winners: André Lwoff (1965), Pierre-Gilles de Gennes (1991), Albert Fert (2007) and Jules Hoffmann (2011). This article focuses on five scientists closely related to the center. The first three are Henri de Lacaze-Duthiers (1821-1901), the founder; Édouard Chatton (1883-1947), eminent director of the center; and André Lwoff (1902-1994), who before being known for his work in bacterial genetics and virology was an outstanding protozoologist under the direction of Chatton. Lynn Margulis (1938-2011), a great friend of the Arago Laboratory and personal friend of the author, is also remembered. Finally, there is a mention of Walter J. Gehring (1939-2014), professor at the University of Basel, Switzerland. [Int Microbiol 19(4): 183-190 (2016)]. Copyright© by the Spanish Society for Microbiology and Institute for Catalan Studies.
The Cincinnati Observatory as a Research Instrument for Undergraduate Research
NASA Astrophysics Data System (ADS)
Abel, Nicholas; Regas, Dean; Flateau, Davin C.; Larrabee, Cliff
2016-06-01
The Cincinnati Observatory, founded in 1842, was the first public observatory in the Western Hemisphere. The history of Cincinnati is closely intertwined with the history of the Observatory, and with the history of science in the United States. Previous directors of the Observatory helped to create the National Weather Service, the Minor Planet Center, and the first astronomical journal in the U.S. The Cincinnati Observatory was internationally known in the late 19th century, with Jules Verne mentioning the Cincinnati Observatory in two of his books, and the Observatory now stands as a National Historic Landmark.No longer a research instrument, the Observatory is now a tool for promoting astronomy education to the general public. However, with the 11" and 16" refracting telescopes, the Observatory telescopes are very capable of collecting data to fuel undergraduate research projects. In this poster, we will discuss the history of the Observatory, types of student research projects capable with the Cincinnati Observatory, future plans, and preliminary results. The overall goal of this project is to produce a steady supply of undergraduate students collecting, analyzing, and interpreting data, and thereby introduce them to the techniques and methodology of an astronomer at an early stage of their academic career.
The history of gait analysis before the advent of modern computers.
Baker, Richard
2007-09-01
Aristotle (384-322 BCE) can be attributed with the earliest recorded comments regarding the manner in which humans walk. It was not until the renaissance that further progress was made through the experiments and theorising of Giovanni Borelli (1608-1679). Although several scientists wrote about walking through the enlightenment period it was the brothers Willhelm (1804-1891) and Eduard (1806-1871) Weber, working in Leipzig who made the next major contribution based on very simple measurements. Both Jules Etienne Marey (1830-1904), working in France, and Eadweard Muybridge (1830-1904), working in America, made significant advances in measurement technology. These were developed further by Otto Fischer (1861-1917) in collaboration with Willhelm Braune (1831-1892). The major developments in the early twentieth century were in the development of force plates and the understanding of kinetics. The team headed by Verne Inman (1905-1980) and Howard Eberhart (1906-1993) made major advances in America shortly after the Second War. David Sutherland (1923-2006) and Jacquelin Perry pioneered clinical applications in America and Jurg Baumann (1926-2000) in Europe. It was not until the advent of modern computers that clinical gait analysis became widely available.
Obituary: Edward W. Burke, Jr. (1924-2011)
NASA Astrophysics Data System (ADS)
Bloomer, Raymond, Jr.
2011-12-01
Dr. Edward W. Burke Jr. passed away on June 15, 2011, after suffering a heart attack. Dr. Burke devoted his professional life to the research and teaching of physics and astronomy at King College in Bristol, Tennessee. Edward W. Burke, Jr., was born in Macon, Georgia, on September 16, 1924. He was a Navy veteran, having been commissioned as an ensign in 1944. He served in the Pacific near the end of World War II. He proceeded to complete his undergraduate degree in mathematics from Presbyterian College in 1947 and pursued the M.S. and Ph.D. in physics (1949 and 1954, respectively) at the University of Wisconsin. Under the direction of Professor Julian Mack, his thesis was titled "Isotope Shift in the Spectra of Boron." Although he did research in atomic spectra in the early part of his career, his interest in astronomy and variable stars in particular were his primary interests during his long academic career. Dr. Burke began his illustrious career at King College in 1949. He initiated the astronomy program there in 1950, included constructing a 12.5 inch Newtonian telescope, homemade as was most everything in those days. Many of his students learned about photometry at the Burke Observatory on the college campus. Burke was known for his trips to the Kitt Peak and Lowell observatories accompanied by undergraduate students on his trips, all of which were made by automobile which he preferred over flying. His initial interest in Ap stars later broadened into variable and especially eclipsing binary stars. His motivation was maintained by his desire to have his students experience basic research and to spark their interest in advanced degrees. Numerous students achieved advanced science and medical degrees because of Burke's encouragement and mentoring. In 1959, Dr. Burke was awarded a Fulbright professorship and traveled to Chile where he taught physics for a year in the Engineering School at the University of Chile in Santiago. He worked to establish a physics program there and upon a return visit in 2003 he found that the university physics program was thriving. In the 52 years of his association with King College, Dr. Burke served in many capacities. Over the years he was the tennis coach, Vice President for Academic Affairs, and Chairman of the Division of Natural Sciences and Mathematics for 31 years until his retirement in 1991. He continued to be involved on campus as a Professor Emeritus until his death. Throughout his career he engaged the public in the wonder of astronomy. He organized the Bristol Astronomy Club for the amateur astronomers in the region. In 1957 he spearheaded the King College Moonwatch program, an international man-made satellite observing program organized by the Smithsonian Astronomical Observatory. He initiated Science Open House at King College, a program which hosted hundreds of talented high school junior and senior students from the Appalachian region, to enjoy tours and demonstrations in the science departments. Throughout his career he opened the Burke Observatory for thousands of interested viewers. Burke was a southern gentleman, true to his roots in Macon, Georgia. At the same time he was also a man who never took "no" for an answer. He always found a way to recommend a way to solve a problem, to get a grant to do research, or to plan another observing trip. He was an eternal optimist who seemed to envision the possibilities rather than the limitations. In addition to his duties at King College, he was a long-time member of the Lions Club where he spent considerable time helping disadvantaged people obtain suitable eyeglasses. He also taught Sunday School at State Street United Methodist Church for many years. He was an avid birdwatcher with the Bristol Bird Club. In his later years he competed in badminton at the Senior Olympics and served as a line judge at the 1996 National Senior Olympics in Atlanta. He was married to Julee Struby Burke for 64 years. Julee was a participant in several research trips out west and served as a constant source of encouragement throughout his long career. Dr. Burke is survived by his wife, Julee, a son, Edward W. Burke, III, a daughter, Julia Burke Torbert (Edgar) and one grandson, Samuel Burke Torbert. An endowed chair has been established in his name at King College: The Edward W. Burke, Jr., Endowed Chair in Natural Science. His legacy to education in the natural sciences in the Appalachian region will continue to inspire future generations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leray, O.; Hudelot, J. P.; Antony, M.
2011-07-01
The new European material testing Jules Horowitz Reactor (JHR), currently under construction in Cadarache center (CEA France), will use LEU (20% enrichment in {sup 235}U) fuels (U{sub 3}Si{sub 2} for the start up and UMoAl in the future) which are quite different from the industrial oxide fuel, for which an extensive neutronics qualification database has been established. The HORUS3D/N neutronics calculation scheme, used for the design and safety studies of the JHR, is being developed within the framework of a rigorous verification-validation-qualification methodology. In this framework, the experimental VALMONT (Validation of Aluminium Molybdenum uranium fuel for Neutronics) program has beenmore » performed in the MINERVE facility of CEA Cadarache (France), in order to qualify the capability of HORUS3D/N to accurately calculate the reactivity of the JHR reactor. The MINERVE facility using the oscillation technique provides accurate measurements of reactivity effect of samples. The VALMONT program includes oscillations of samples of UAl{sub x}/Al and UMo/Al with enrichments ranging from 0.2% to 20% and Uranium densities from 2.2 to 8 g/cm{sup 3}. The geometry of the samples and the pitch of the experimental lattice ensure maximum representativeness with the neutron spectrum expected for JHR. By comparing the effect of the sample with the one of a known fuel specimen, the reactivity effect can be measured in absolute terms and be compared to computational results. Special attention was paid to the rigorous determination and reduction of the experimental uncertainties. The calculational analysis of the VALMONT results was performed with the French deterministic code APOLLO2. A comparison of the impact of the different calculation methods, data libraries and energy meshes that were tested is presented. The interpretation of the VALMONT experimental program allowed the qualification of JHR fuel UMoAl8 (with an enrichment of 19.75% {sup 235}U) by the Minerve-dedicated interpretation tool: PIMS. The effect of energy meshes and evaluations put forward the JEFF3.1.1/SHEM scheme that leads to a better calculation of the reactivity effect of VALMONT samples. Then, in order to quantify the impact of the uncertainties linked to the basic nuclear data, their propagation from the cross section measurement to the final computational result was analysed in a rigorous way by using a nuclear data re-estimation method based on Gauss-Newton iterations. This study concludes that the prior uncertainties due to nuclear data (uranium, aluminium, beryllium and water) on the reactivity of the Begin Of Cycle (BOC) for the JHR core reach 1217 pcm at 2{sigma}. Now, the uppermost uncertainty on the JHR reactivity is due to aluminium. (authors)« less
Secondary structure adventures with Carl Woese
Noller, Harry F
2014-01-01
Not long after my arrival at UCSC as an assistant professor, I came across Carl Woese's paper “Molecular Mechanics of Translation: A Reciprocating Ratchet Mechanism.”1 In the days before the crystal structure of tRNA was known, Fuller and Hodgson2 had proposed two alternative conformations for its anticodon loop; one was stacked on the 3′ side (as later found in the crystal structure) and the other on the 5′ side. In an ingenious and elegant model, Woese proposed that the conformation of the loop flips between Fuller and Hodgson's 5′- and 3′-stacked forms during protein synthesis, changing the local direction of the mRNA such that the identities of the tRNA binding sites alternated between binding aminoacyl-tRNA and peptidyl-tRNA. The model predicted that there are no A and P sites, only two binding sites whose identities changed following translation of each codon, and that there would be no translocation of tRNAs in the usual sense—only binding and release. I met Carl in person the following year when he presented a seminar on his ratchet model in Santa Cruz. He was chatting in my colleague Ralph Hinegardner's office in what Carl termed a “Little Jack Horner appointment” (the visitor sits and listens to his host describing “What a good boy am I”). He was of compact stature, and bore a striking resemblance to Oskar Werner in Truffaut's film “Jules and Jim.” He projected the impression of a New-Age guru—a shiny black amulet suspended over the front of his black turtleneck sweater and a crown of prematurely white hair. Ralph asked me to explain to Carl what we were doing with ribosomes. I quickly summarized our early experiments that were pointing to a functional role for 16S rRNA. Carl regarded me silently, with a penetrating stare. He then turned to Ralph and said, in an ominous low voice, “I'm going to have some more tanks made as soon as I get back.” Carl's beautiful model was, unfortunately, wrong—it was simpler and more elegant than the complex mechanism that Nature actually uses. Unyielding, Carl railed against the A-site-P-site model at every opportunity,3,4 and although we ended up enjoying a long, intense, and fruitful collaboration, and became close, life-long friends, I finally gave up trying to describe to him our biochemical and crystallographic results on the A, P, and E sites. PMID:24637459
Performance assessment of imaging plates for the JHR transfer Neutron Imaging System
NASA Astrophysics Data System (ADS)
Simon, E.; Guimbal, P. AB(; )
2018-01-01
The underwater Neutron Imaging System to be installed in the Jules Horowitz Reactor (JHR-NIS) is based on a transfer method using a neutron activated beta-emitter like Dysprosium. The information stored in the converter is to be offline transferred on a specific imaging system, still to be defined. Solutions are currently under investigation for the JHR-NIS in order to anticipate the disappearance of radiographic films commonly used in these applications. We report here the performance assessment of Computed Radiography imagers (Imaging Plates) performed at LLB/Orphée (CEA Saclay). Several imaging plate types are studied, in one hand in the configuration involving an intimate contact with an activated dysprosium foil converter: Fuji BAS-TR, Fuji UR-1 and Carestream Flex XL Blue imaging plates, and in the other hand by using a prototypal imaging plate doped with dysprosium and thus not needing any contact with a separate converter foil. The results for these imaging plates are compared with those obtained with gadolinium doped imaging plate used in direct neutron imaging (Fuji BAS-ND). The detection performances of the different imagers are compared regarding resolution and noise. The many advantages of using imaging plates over radiographic films (high sensitivity, linear response, high dynamic range) could palliate its lower intrinsic resolution.
Cao, Liping; Yin, Guojun; Cao, Zheming; Bing, Xuwen; Ding, Weidong
2016-06-01
A Ty3/gypsy-retrotransposon-type transposon was found in the genome of the Jian carp (Cyprinus carpio var. Jian) in a previous study (unpublished), and was designated a JRE retrotransposon (Jian retrotransposon). The full-length JRE retrotransposon is 5126 bp, which includes two long terminal repeats of 470 bp at the 5' end and 453 bp at the 3' end, and two open reading frames between them: 4203 bp encoding the group-specific antigen (GAG) and polyprotein (POL). The pol gene has a typical Ty3/gypsy retrotransposon structure, and the gene order is protease, reverse transcriptase, RNase H, and integrase (PR-RT-RH-IN). A phylogenetic analysis of the pol gene showed that it has similarities of 40.7, 40, and 32.8 %, to retrotransposons of Azumapecten farreri, Mizuhopecten yessoensis, and Xiphophorus maculatus, respectively. Therefore, JRE might belong to the JULE retrotransposon family. The copy number of the JRE transposon in the genome of the Jian carp is 124, determined with real-time quantitative PCR. The mRNA of the JRE retrotransposon is expressed in five Jian carp tissues, the liver, kidney, blood, muscle, and gonad, and slightly higher in the kidney and liver than in the other tissues.
Murányi, Dávid; Gamboa, Maribet; Vera, Alejandro
2016-12-01
Types of five of the six Plecoptera species described by Émile Blanchard and the holotype of the single stonefly described by Jules François Mabille were discovered in the National Museum Prague, Czech Republic. The identity of P. myrmidon Mabille, 1891 and P. pictetii Blanchard, 1854 are confirmed as Potamoperla myrmidon and Pictetoperla gayi (Pictet, 1841), respectively. Perla virescentipennis Blanchard, 1851 is considered as Diamphipnopsis virescentipennis comb. n., with Diamphipnosis samali Illies, 1960 syn. n. as a junior subjective synonym, and Diamphipnoa chillanae nom. n. is proposed for D. virescentipennis sensu Illies 1960. Lectotypes are designated for three species: Nemoura rufescens Blanchard, 1851 is redescribed as Austronemoura rufescens (Blanchard, 1851) comb. n., with Perla infuscata Blanchard, 1851 syn. n. and Perla blanchardi Jakobson & Bianchi, 1905 syn. n. designated as junior subjective synonyms, whereas Perla stictica Blanchard, 1851 is treated as Neonemura stictica (Blanchard, 1851) comb. n., nomen dubium. Paralectotypes of these three species belong to further four taxa. Due to the missing syntypes, Perla lineatocollis Blanchard, 1851 is treated as a nomen dubium of uncertain suborder assignment. Specimens of the Blanchard collections that cannot regarded as types are enumerated belonging to six species. Recent collections of 15 species from Chile are also reported.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guimbal, P.; Huotilainen, S.; Taehtinen, S.
2015-07-01
As a prototype of future instrumented material experiments in the Jules Horowitz Reactor (JHR), the MELODIE project was launched in 2009 by the CEA in collaboration with VTT. Being designed as a biaxial creep experiment with online capability, MELODIE is able to apply an online-controlled biaxial loading on a LWR clad sample up to 120 MPa and to perform an online measurement of its biaxial deformation. An important experimental challenge was to perform reliably accurate measurements under the high nuclear heat load of in-core locations while keeping within their tight space. For that purpose, specific sensors were co-designed with andmore » built by IFE Halden. Manufacturing of the MELODIE components was completed one year ago. The complexity of its in-pile section and of the pressurization system requested a step-by-step tuning of the setup. The toughest part of this process dealt with the Diameter gauge which required a partial redesign to take into account unexpected and unwanted electromagnetic interactions with the hosting device. Final cold performance tests of the on-board instrumentation will be presented. The MELODIE device is now ready and irradiation should start in OSIRIS reactor this spring. (authors)« less
Cats on the Couch: The Experimental Production of Animal Neurosis.
Winter, Alison
2016-03-01
Argument In the 1940s-50s, one of the most central questions in psychological research related to the nature of neurosis. In the final years of the Second World War and the following decade, neurosis became one of the most prominent psychiatric disorders, afflicting a high proportion of military casualties and veterans. The condition became central to the concerns of several psychological fields, from psychoanalysis to Pavlovian psychology. This paper reconstructs the efforts of Chicago psychiatrist Jules Masserman to study neurosis in the laboratory during the 1940s and 1950s. Masserman used Pavlovian techniques in a bid to subject this central psychoanalytic subject to disciplined scientific experimentation. More generally, his project was an effort to bolster the legitimacy of psychoanalysis as a human science by articulating a convergence of psychoanalytic categories across multiple species. Masserman sought to orchestrate a convergence of psychological knowledge between fields that were often taken to be irreconcilable. A central focus of this paper is the role of moving images in this project, not only as a means of recording experimental data but also as a rhetorical device. The paper argues that for Masserman film played an important role in enabling scientific observers (and then subsequent viewers) to see agency and emotion in the animals they observed.
Heat production: Longitudinal versus torsional phacoemulsification.
Han, Young Keun; Miller, Kevin M
2009-10-01
To compare the heat production of longitudinal versus torsional phacoemulsification under strict laboratory test conditions. Department of Ophthalmology, David Geffen School of Medicine at UCLA, and Jules Stein Eye Institute, Los Angeles, California, USA. Two Infiniti phacoemulsification handpieces were inserted into silicone test chambers filled with a balanced salt solution and imaged serially using a thermal camera. Incision compression was simulated by suspending 25.3 g weights from the silicone chambers. To simulate occlusion of the phacoemulsification tip, the aspiration line was clamped. Peak temperatures were measured 0, 10, 30, 60, and 120 seconds after the commencement of continuous ultrasound power. The 2 handpieces, operating exclusively in longitudinal or torsional modes, were compared 3 ways: (1) using the same power displayed on the instrument console, (2) using identical stroke lengths, and (3) using the same applied energy, a product of stroke length and frequency. For all 3 comparisons, torsional phacoemulsification resulted in lower temperatures at each time point. At the same displayed power setting, the scenario most familiar to cataract surgeons, longitudinal phacoemulsification elevated temperatures up to 41.5 degrees C more than torsional phacoemulsification. Torsional phacoemulsification generated less heat than longitudinal phacoemulsification in all 3 comparison tests. Lower operating temperatures indicate lower heat generation within the same volume of fluid, and this may provide additional thermal protection during cataract surgery.
Photogenic Venus. The "cinematographic turn" and its alternatives in nineteenth-century France
NASA Astrophysics Data System (ADS)
Canales, Jimena
2002-12-01
During the late nineteenth century, scientists around the world disagreed as to the types of instruments and methods that should be used for determining the most important constant of celestial mechanics: the solar parallax. Venus's 1874 transit across the sun was seen as the best opportunity for ending decades of debate. However, a mysterious "black drop" that appeared between Venus and the sun and individual differences in observations of the phenomenon brought traditional methods into disrepute. To combat these difficulties, the astronomer Jules Janssen devised a controversial new instrument, the "photographic revolver", that photographed Venus at regular intervals. Another solution came from physicists, who rivaled the astronomers' dominance in precision measurements by deducing the solar parallax from physical measurements of the speed of light. Yet other astronomers relied on drawings and well-trained observers. The new space emerging from this debate was characterized by a decline in faith in (nonstandardized, nonreproducible) photography and in (pure) geometry and by the growing realization of the importance of alternative elements needed for establishing scientific truths: power and authority, skill and discipline, standardization, mechanical reproducibility, and theoreticality. By examining the "cinematographic turn" in science and its alternatives, this essay brings to light unexplored multi-disciplinary connections that contribute to the histories of psychology, philosophy, physics, and film studies.
Lahaie, Yves-Marie
2017-01-01
ABSTRACT The history of antimicrobial humoral immunity usually focuses on the works of the German school at the end of the 19th century, born in the tradition of chemistry and disinfection. Starting from an old quarrel of priority about serotherapy between Emil von Behring (1854–1917) and the French physiologists Charles Richet (1850–1935) and Jules Héricourt (1850–1938), we first confirm that the latter stated the principle of serotherapy in 1888 and put it into practice before the seminal Behring's article in 1890, observing several adverse effects of this new immunotherapy. We also find that researchers who can be considered heirs of the French school of Physiology founded by Claude Bernard (1813–1878) also investigated the field of humoral immunity in the 1870–1880s. Maurice Raynaud (1834–1881), Auguste Chauveau (1827–1917), and eventually Charles Richet applied the experimental method of Claude Bernard to the young field of microbiology, illustrating a movement called by Jacques Léonard “physiologization of the pasteurism.” However, the contribution of physiologists in this field started before Louis Pasteur, leading to the conclusion that physiologists and chemists synergistically contributed to the birth of bacteriology and immunology. PMID:28557665
Chronicler's Induction Ceremony
2017-05-05
"The Chroniclers," a program at NASA’s Kennedy Space Center, Florida, recognizing those who helped spread news of American space exploration, officially added six new names to its wall of fame in a ceremony on May 5, 2017. This year’s honorees are, in alphabetical order: Bruce Hall, veteran CBS News and NBC News correspondent and producer (deceased); Scott Harris, veteran Orlando TV reporter and anchor (deceased); Bill Johnson, NASA Kennedy Public Affairs (retired); Warren Leary, science writer and correspondent for the Associated Press and The New York Times (retired); Robert B. (Bob) Murray, NASA videographer and technician (retired); and Phil Sandlin, photographer for UPI and The Associated Press (retired). Brass strips engraved with each awardee’s name and affiliation were unveiled on “The Chroniclers” wall in the newsroom at the Kennedy Space Center Press Site. Sixty-six past honorees include Walter Cronkite of CBS News, Jules Bergman of ABC News and two-time Pulitzer winner John Noble Wilford of The New York Times. Today’s ceremony came on the 56th anniversary of Alan Shepard’s historic flight as America’s first human in space. Coincidentally, it was Shepard from whom the first “Chroniclers” received their award certificates in 1996. KSC Contact - Al Feinberg (321)867-2468, al.feinberg@nasa.gov
Loison, Laurent; Gayon, Jean; Burian, Richard M
2017-02-01
This article shows how Lamarckism was essential in the birth of the French school of molecular biology. We argue that the concept of inheritance of acquired characters positively shaped debates surrounding bacteriophagy and lysogeny in the Pasteurian tradition during the interwar period. During this period the typical Lamarckian account of heredity treated it as the continuation of protoplasmic physiology in daughter cells. Félix d'Hérelle applied this conception to argue that there was only one species of bacteriophage and Jules Bordet applied it to develop an account of bacteriophagy as a transmissible form of autolysis and to analyze the new phenomenon of lysogeny. In a long-standing controversy with Bordet, Eugène Wollman deployed a more morphological understanding of the inheritance of acquired characters, yielding a particulate, but still Lamarckian, account of lysogeny. We then turn to André Lwoff who, with several colleagues, completed Wollman's research program from 1949 to 1953. We examine how he gradually set aside the Lamarckian background, finally removing inheritance of acquired characters from the resulting account of bacteriophagy and lysogeny. In the conclusion, we emphasize the complex dual role of Lamarckism as it moved from an assumed explanatory framework to a challenge that the nascent molecular biology had to overcome.
Metals and magnets in medicine: hysteria, hypnosis and medical culture in fin-de-siècle Paris.
Harrington, A
1988-02-01
It is well known that the end of the nineteenth century represented a 'golden age' of hysteria and hypnosis research under Jean-Martin Charcot in Paris, but the extent to which metals and magnets figured in this strange and provocative world has been very incompletely told. This paper offers itself as a first corrective to this neglect. In 1876 a certain elderly physician and mesmerist, Victor Burq, asked the Parisian Société de Biologie formally to establish the validity of his so-called 'metallotherapy' (later 'metalloscopy') treatment for hysteria. The paper argues that Charcot's participation in the investigation of Burq's work--undertaken in conjunction with two other leading French neurologists, Amédée Dumontpallier and Jules Bernard Luys--served as a major catalyst in arousing the great neurologist's interest in hypnosis in the first place, and was subsequently responsible for several of his key beliefs about the underlying physiological link between hypnosis and hysteria. It is also shown how these early metalloscopy studies--and especially the discovery by Charcot and his colleagues of so-called metalloscopic 'transfer'--opened the door to the rise of a neo-mesmeric, and increasingly occult, branch of hypnosis research in French psychiatry, which has to date, in the secondary literature, gone almost wholly unremarked.
Computing Incompressible Flows With Free Surfaces
NASA Technical Reports Server (NTRS)
Kothe, D.
1994-01-01
RIPPLE computer program models transient, two-dimensional flows of incompressible fluids with surface tension on free surfaces of general shape. Surface tension modeled as volume force derived from continuum-surface-force model, giving RIPPLE both robustness and accuracy in modeling surface-tension effects at free surface. Also models wall adhesion effects. Written in FORTRAN 77.
Needs of Accurate Prompt and Delayed γ-spectrum and Multiplicity for Nuclear Reactor Designs
NASA Astrophysics Data System (ADS)
Rimpault, G.; Bernard, D.; Blanchet, D.; Vaglio-Gaudard, C.; Ravaux, S.; Santamarina, A.
The local energy photon deposit must be accounted accurately for Gen-IV fast reactors, advanced light-water nuclear reactors (Gen-III+) and the new experimental Jules Horowitz Reactor (JHR). The γ energy accounts for about 10% of the total energy released in the core of a thermal or fast reactor. The γ-energy release is much greater in the core of the reactor than in its structural sub-assemblies (such as reflector, control rod followers, dummy sub-assemblies). However, because of the propagation of γ from the core regions to the neighboring fuel-free assemblies, the contribution of γ energy to the total heating can be dominant. For reasons related to their performance, power reactors require a 7.5% (1σ) uncertainty for the energy deposition in non-fuelled zones. For the JHR material-testing reactor, a 5% (1 s) uncertainty is required in experimental positions. In order to verify the adequacy of the calculation of γ-heating, TLD and γ-fission chambers were used to derive the experimental heating values. Experimental programs were and are still conducted in different Cadarache facilities such as MASURCA (for SFR), MINERVE and EOLE (for JHR and Gen-III+ reactors). The comparison of calculated and measured γ-heating values shows an underestimation in all experimental programs indicating that for the most γ-production data from 239Pu in current nuclear-data libraries is highly suspicious.The first evaluation priority is for prompt γ-multiplicity for U and Pu fission but similar values for otheractinides such as Pu and U are also required. The nuclear data library JEFF3.1.1 contains most of the photon production data. However, there are some nuclei for which there are missing or erroneous data which need to be completed or modified. A review of the data available shows a lack of measurements for conducting serious evaluation efforts. New measurements are needed to guide new evaluation efforts which benefit from consolidated modeling techniques.
Lunar farside volcanism in and around the South Pole-Aitken basin
NASA Astrophysics Data System (ADS)
Pasckert, Jan Hendrik; Hiesinger, Harald; van der Bogert, Carolyn H.
2018-01-01
We identified and mapped 129 mare basalt deposits in and around the South Pole-Aitken (SPA) basin, and determined absolute model ages (AMAs) for 101 of these units by performing crater size-frequency distribution (CSFD) measurements. The derived AMAs range from 2.2 Ga to 3.7 Ga, with the youngest deposits within Antoniadi crater and the oldest deposits at Jules Verne crater. Our investigations indicate a major peak in volcanic activity between 3.6 Ga and 3.2 Ga, which is a similar time range as the major volcanic activity on the nearside, and the rest of the farside. However, a second peak in volcanic activity (2.2-2.5 Ga), as observed for the nearside and parts of the farside, is not observed for the mare deposits within the SPA basin. Combining all AMAs derived for farside mare basalts reveals that volcanic activity was more abundant and lasted longer on the nearside than on the farside. We propose that the stripping of insulating crust by the large SPA-forming impact event, in combination with lower amounts of heat producing elements like Th, might be responsible for the reduced volcanic activity in the SPA basin. In addition, we estimated the thicknesses and volumes of the investigated mare deposits. With thicknesses between ∼31 m and ∼273 m and volumes of ∼1 km³ to ∼2630 km³, the mare basalt deposits in and around the SPA basin show a wide range of dimensions, similar to other mare basalts of the near- and farsides. A trend between the AMAs and the estimated volumes was not observed, but the mare deposits within the large northern craters (e.g., Apollo, Ingenii, or Leibnitz) seem to be generally larger and more voluminous than the mare basalt deposits at the center of the SPA basin.
Zhang, Lijun; Danesh, Jennifer; Tannan, Anjali; Phan, Vivian; Yu, Fei; Hamilton, D Rex
2015-10-01
To evaluate the difference in corneal biomechanical waveform parameters between manifest keratoconus, forme fruste keratoconus, and healthy eyes with a second-generation biomechanical waveform analyzer (Ocular Response Analyzer 2). Jules Stein Eye Institute, University of California, Los Angeles, California, USA. Retrospective chart review. The biomechanical waveform analyzer was used to obtain corneal hysteresis (CH), corneal resistance factor (CRF), and 37 biomechanical waveform parameters in manifest keratoconus eyes, forme fruste keratoconus eyes, and healthy eyes. Useful distinguishing parameters were found using t tests and a multivariable logistic regression model with stepwise variable selection. Potential confounders were controlled for. The study included 68 manifest keratoconus eyes, 64 forme fruste keratoconus eyes, and 249 healthy eyes. There was a statistical difference in the mean CRF between the normal group (10.2 mm Hg ± 1.7 [SD]) and keratoconus group (6.3 ± 1.9 mm Hg) (P = .003), and between the normal group and the forme fruste keratoconus group (7.8 ± 1.4 mm Hg) (P < .0001). There was no statistical difference in the mean CH between the normal group and the keratoconus group or the forme fruste keratoconus group. The CRF, height of peak 1 (P1) (P = .001), downslope of P1 (dslope1) (P = .027), upslope of peak 2 (P2) (P = .004), and downslope of P2 (P = .006) distinguished the normal group from the keratoconus groups. The CRF, downslope of P2 derived from upper 50% of applanation peak (P = .035), dslope1 (P = .014), and upslope of P1 (P = .008) distinguished the normal group from the forme fruste keratoconus group. Differences in multiple biomechanical waveform parameters can differentiate between healthy and diseased conditions and might improve early diagnosis of keratoconus and forme fruste keratoconus. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.
Surface models of the male urogenital organs built from the Visible Korean using popular software
Shin, Dong Sun; Park, Jin Seo; Shin, Byeong-Seok
2011-01-01
Unlike volume models, surface models, which are empty three-dimensional images, have a small file size, so they can be displayed, rotated, and modified in real time. Thus, surface models of male urogenital organs can be effectively applied to an interactive computer simulation and contribute to the clinical practice of urologists. To create high-quality surface models, the urogenital organs and other neighboring structures were outlined in 464 sectioned images of the Visible Korean male using Adobe Photoshop; the outlines were interpolated on Discreet Combustion; then an almost automatic volume reconstruction followed by surface reconstruction was performed on 3D-DOCTOR. The surface models were refined and assembled in their proper positions on Maya, and a surface model was coated with actual surface texture acquired from the volume model of the structure on specially programmed software. In total, 95 surface models were prepared, particularly complete models of the urinary and genital tracts. These surface models will be distributed to encourage other investigators to develop various kinds of medical training simulations. Increasingly automated surface reconstruction technology using commercial software will enable other researchers to produce their own surface models more effectively. PMID:21829759
Snow drift: acoustic sensors for avalanche warning and research
NASA Astrophysics Data System (ADS)
Lehning, M.; Naaim, F.; Naaim, M.; Brabec, B.; Doorschot, J.; Durand, Y.; Guyomarc'h, G.; Michaux, J.-L.; Zimmerli, M.
Based on wind tunnel measurements at the CSTB (Jules Verne) facility in Nantes and based on field observations at the SLF experimental site Versuchsfeld Weissfluhjoch, two acoustic wind drift sensors are evaluated against different mechanical snow traps and one optical snow particle counter. The focus of the work is the suitability of the acoustic sensors for applications such as avalanche warning and research. Although the acoustic sensors have not yet reached the accuracy required for typical research applications, they can, however, be useful for snow drift monitoring to help avalanche forecasters. The main problem of the acoustic sensors is a difficult calibration that has to take into account the variable snow properties. Further difficulties arise from snow fall and high wind speeds. However, the sensor is robust and can be operated remotely under harsh conditions. It is emphasized that due to the lack of an accurate reference method for snow drift measurements, all sensors play a role in improving and evaluating snow drift models. Finally, current operational snow drift models and snow drift sensors are compared with respect to their usefulness as an aid for avalanche warning. While drift sensors always make a point measurement, the models are able to give a more representative drift index that is valid for a larger area. Therefore, models have the potential to replace difficult observations such as snow drift in operational applications. Current models on snow drift are either only applicable in flat terrain, are still too complex for an operational application (Lehning et al., 2000b), or offer only limited information on snow drift, such as the SNOWPACK drift index (Lehning et al., 2000a). On the other hand, snow drift is also difficult to measure. While mechanical traps (Mellor 1960; Budd et al., 1966) are probably still the best reference, they require more or less continuous manual operation and are thus not suitable for remote locations or long-term monitoring. Optical sensors (Schmidt, 1977; Brown and Pomeroy, 1989; Sato and Kimura, 1993) have been very successful for research applications, but suffer from the fact that they give a single flux value at one specific height. In addition, they have not been used, to our knowledge, for long-term monitoring applications or at remote sites. New developments of acoustic sensors have taken place recently (Chritin et al., 1999; Font et al., 1998). Jaedicke (2001) gives examples of possible applications of acoustic snow drift sensors. He emphasizes the advantages of acoustic sensors for snow drift monitoring at remote locations, but could not present any evaluation of the accuracy of the measurements. We present a complete evaluation of the new acoustic sensors for snow drift and discuss their applications for research or avalanche warning. We compare the suitability of sensors for operational applications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tarchalski, M.; Pytel, K.; Wroblewska, M.
2015-07-01
Precise computational determination of nuclear heating which consists predominantly of gamma heating (more than 80 %) is one of the challenges in material testing reactor exploitation. Due to sophisticated construction and conditions of experimental programs planned in JHR it became essential to use most accurate and precise gamma heating model. Before the JHR starts to operate, gamma heating evaluation methods need to be developed and qualified in other experimental reactor facilities. This is done inter alia using OSIRIS, MINERVE or EOLE research reactors in France. Furthermore, MARIA - Polish material testing reactor - has been chosen to contribute to themore » qualification of gamma heating calculation schemes/tools. This reactor has some characteristics close to those of JHR (beryllium usage, fuel element geometry). To evaluate gamma heating in JHR and MARIA reactors, both simulation tools and experimental program have been developed and performed. For gamma heating simulation, new calculation scheme and gamma heating model of MARIA have been carried out using TRIPOLI4 and APOLLO2 codes. Calculation outcome has been verified by comparison to experimental measurements in MARIA reactor. To have more precise calculation results, model of MARIA in TRIPOLI4 has been made using the whole geometry of the core. This has been done for the first time in the history of MARIA reactor and was complex due to cut cone shape of all its elements. Material composition of burnt fuel elements has been implemented from APOLLO2 calculations. An experiment for nuclear heating measurements and calculation verification has been done in September 2014. This involved neutron, photon and nuclear heating measurements at selected locations in MARIA reactor using in particular Rh SPND, Ag SPND, Ionization Chamber (all three from CEA), KAROLINA calorimeter (NCBJ) and Gamma Thermometer (CEA/SCK CEN). Measurements were done in forty points using four channels. Maximal nuclear heating evaluated from measurements is of the order of 2.5 W/g at half of the possible MARIA power - 15 MW. The approach and the detailed program for experimental verification of calculations will be presented. The following points will be discussed: - Development of a gamma heating model of MARIA reactor with TRIPOLI 4 (coupled neutron-photon mode) and APOLLO2 model taking into account the key parameters like: configuration of the core, experimental loading, control rod location, reactor power, fuel depletion); - Design of specific measurement tools for MARIA experiments including for instance a new single-cell calorimeter called KAROLINA calorimeter; - MARIA experimental program description and a preliminary analysis of results; - Comparison of calculations for JHR and MARIA cores with experimental verification analysis, calculation behavior and n-γ 'environments'. (authors)« less
Symons, Jennifer E; Fyhrie, David P; Hawkins, David A; Upadhyaya, Shrinivasa K; Stover, Susan M
2015-02-26
Race surfaces have been associated with the incidence of racehorse musculoskeletal injury, the leading cause of racehorse attrition. Optimal race surface mechanical behaviors that minimize injury risk are unknown. Computational models are an economical method to determine optimal mechanical behaviors. Previously developed equine musculoskeletal models utilized ground reaction floor models designed to simulate a stiff, smooth floor appropriate for a human gait laboratory. Our objective was to develop a computational race surface model (two force-displacement functions, one linear and one nonlinear) that reproduced experimental race surface mechanical behaviors for incorporation in equine musculoskeletal models. Soil impact tests were simulated in a musculoskeletal modeling environment and compared to experimental force and displacement data collected during initial and repeat impacts at two racetracks with differing race surfaces - (i) dirt and (ii) synthetic. Best-fit model coefficients (7 total) were compared between surface types and initial and repeat impacts using a mixed model ANCOVA. Model simulation results closely matched empirical force, displacement and velocity data (Mean R(2)=0.930-0.997). Many model coefficients were statistically different between surface types and impacts. Principal component analysis of model coefficients showed systematic differences based on surface type and impact. In the future, the race surface model may be used in conjunction with previously developed the equine musculoskeletal models to understand the effects of race surface mechanical behaviors on limb dynamics, and determine race surface mechanical behaviors that reduce the incidence of racehorse musculoskeletal injury through modulation of limb dynamics. Copyright © 2015 Elsevier Ltd. All rights reserved.
Understanding Surface Adhesion in Nature: A Peeling Model.
Gu, Zhen; Li, Siheng; Zhang, Feilong; Wang, Shutao
2016-07-01
Nature often exhibits various interesting and unique adhesive surfaces. The attempt to understand the natural adhesion phenomena can continuously guide the design of artificial adhesive surfaces by proposing simplified models of surface adhesion. Among those models, a peeling model can often effectively reflect the adhesive property between two surfaces during their attachment and detachment processes. In the context, this review summarizes the recent advances about the peeling model in understanding unique adhesive properties on natural and artificial surfaces. It mainly includes four parts: a brief introduction to natural surface adhesion, the theoretical basis and progress of the peeling model, application of the peeling model, and finally, conclusions. It is believed that this review is helpful to various fields, such as surface engineering, biomedicine, microelectronics, and so on.
Numerical study of electromagnetic scattering from one-dimensional nonlinear fractal sea surface
NASA Astrophysics Data System (ADS)
Xie, Tao; He, Chao; William, Perrie; Kuang, Hai-Lan; Zou, Guang-Hui; Chen, Wei
2010-02-01
In recent years, linear fractal sea surface models have been developed for the sea surface in order to establish an electromagnetic backscattering model. Unfortunately, the sea surface is always nonlinear, particularly at high sea states. We present a nonlinear fractal sea surface model and derive an electromagnetic backscattering model. Using this model, we numerically calculate the normalized radar cross section (NRCS) of a nonlinear sea surface. Comparing the averaged NRCS between linear and nonlinear fractal models, we show that the NRCS of a linear fractal sea surface underestimates the NRCS of the real sea surface, especially for sea states with high fractal dimensions, and for dominant ocean surface gravity waves that are either very short or extremely long.
Birmingham Urban Climate Change with Neighbourhood Estimates of Environmental Risk (buccaneer)
NASA Astrophysics Data System (ADS)
Bassett, R.; Thornes, J.; Cai, X.; Rees, R.
2011-12-01
The BUCCANEER project is a knowledge transfer partnership between the University of Birmingham and Birmingham City Council to help ensure that the city is prepared for the impacts of climate change. The project will equip service areas such as planners and health protection agencies with the necessary information and tools needed to adapt. UK climate projections indicate a 3.7oC temperature increase for Birmingham, UK by 2080 (medium emissions scenario). The 2003 heat-wave that caused over 2000 deaths in England and Wales will become an average summer by 2040. By the end of the century, the 2003 heat wave will be considered a cool summer. The dense urban fabric of Birmingham, the UK's second largest city, creates a warming effect when compared to surrounding rural areas. Past studies have found the nature of this urban heat island (UHI) to be related to city size, moisture availability, land-use, anthropogenic emissions, building materials and geometry. The UHI effect can lead to heat stress and air pollution problems which are a major health concern. Birmingham's UHI is not currently modelled. More specifically the UK climate projections treat Birmingham as a homogeneous slab of grassland. The inclusions of the urban areas in a climate model will show an intensification of the likely heat risk in future projections. In the present study, the JULES (Joint UK Land Environment Simulator) model has been setup and run for Birmingham and surrounding areas. The UHI was found to be greater than 3.5oC in Birmingham when modelled during heat waves. The model's performance is evaluated against data from two UK Met Office standard sites: Edgbaston (urban) and Winterbourne (rural). The temperatures predicted by the model over a 12 month (2010) simulation show a strong correlation with the observations. The model also reproduces the diurnal UHI intensity averaged over a year reasonably well. The model evaluation is also complemented by a data set of tiny-tag data logger temperature measurements around Birmingham and an on-going project (HiTemp) which aims to establish a high-density urban climate network in Birmingham. Once fully validated, UKCP09 weather generator data will be used to drive the model up to 2100 to assess future changes in Birmingham's climate and UHI. The findings of the research are transferred to Birmingham City Council so as to directly inform policy. In order for this to be achieved, a user-friendly web interface has been created - The BUCCANEER Planning Tool. The tool visually displays the combined impacts of the urban heat island, climate change and vulnerability on different temporal and spatial scales across the city. The vulnerability aspect uses layers developed from a risk mapping project at the University of Birmingham using social, economic and environmental data to create a spatial risk assessment with a particular focus on health and demographics. For example proportion of people with ill health in high density housing that will be exposed to excess heat. Additionally model parameters will be adjusted to allow for adaptation strategies to be assessed, for example the effectiveness of inserting green infrastructure in areas to combat excess heat in the city.
Understanding Surface Adhesion in Nature: A Peeling Model
Gu, Zhen; Li, Siheng; Zhang, Feilong
2016-01-01
Nature often exhibits various interesting and unique adhesive surfaces. The attempt to understand the natural adhesion phenomena can continuously guide the design of artificial adhesive surfaces by proposing simplified models of surface adhesion. Among those models, a peeling model can often effectively reflect the adhesive property between two surfaces during their attachment and detachment processes. In the context, this review summarizes the recent advances about the peeling model in understanding unique adhesive properties on natural and artificial surfaces. It mainly includes four parts: a brief introduction to natural surface adhesion, the theoretical basis and progress of the peeling model, application of the peeling model, and finally, conclusions. It is believed that this review is helpful to various fields, such as surface engineering, biomedicine, microelectronics, and so on. PMID:27812476
High frequency acoustic propagation under variable sea surfaces
NASA Astrophysics Data System (ADS)
Senne, Joseph
This dissertation examines the effects of rough sea surfaces and sub-surface bubbles on high frequency acoustic transmissions. Owing to the strong attenuation of electromagnetic waves in seawater, acoustic waves are used in the underwater realm much in the same way that electromagnetic waves are used in the atmosphere. The transmission and reception of acoustic waves in the underwater environment is important for a variety of fields including navigation, ocean observation, and real-time communications. Rough sea surfaces and sub-surface bubbles alter the acoustic signals that are received not only in the near-surface water column, but also at depth. This dissertation demonstrates that surface roughness and sub-surface bubbles notably affect acoustic transmissions with frequency ranges typical of underwater communications systems (10-50 kHz). The influence of rough surfaces on acoustic transmissions is determined by modeling forward propagation subject to sea surface dynamics that vary with time scales of less than a second to tens of seconds. A time-evolving rough sea surface model is combined with a rough surface formulation of a parabolic equation model for predicting time-varying acoustic fields. Linear surface waves are generated from surface wave spectra, and evolved in time using a Runge-Kutta integration technique. This evolving, range-dependent surface information is combined with other environmental parameters and fed into the acoustic model, giving an approximation of the time-varying acoustic field. The wide-angle parabolic equation model manages the rough sea surfaces by molding them into the boundary conditions for calculations of the near-surface acoustic field. The influence of sub-surface bubbles on acoustic transmissions is determined by modeling the population of bubbles near the surface and using those populations to approximate the effective changes in sound speed and attenuation. Both range-dependent and range-independent bubble models are considered, with the range-dependent model varying over the same time scales as the sea surface model and the range-independent model invariant over time. The bubble-induced sound speed and attenuation fluctuations are read in by the parabolic equation model, which allows for the effects of surface roughness and sub-surface bubbles to be computed separately or together. These merged acoustic models are validated using concurrently-collected acoustic and environmental information, including surface wave spectra. Data to model comparisons demonstrate that the models are able to approximate the ensemble-averaged acoustic intensity at ranges of at least a kilometer for acoustic signals of 10-20 kHz. The rough surface model is shown to capture variations due to surface fluctuations occurring over time scales of less than a second to tens of seconds. The separate bubble models demonstrate the abilities to account for the intermittency of bubble plumes and to determine overall effect of bubbly layers, respectively. The models are shown to capture variations in the acoustic field occurring over time scales of less than a second to tens of seconds. Comparisons against data demonstrate the ability of the model to track acoustic transmissions under evolving sea surfaces. The effects of the evolving bubble field are demonstrated through the use of idealized test cases. For frequency ranges important to communications, surface roughness is shown to have the more dominant effect, with bubbles having an ancillary effect.
Replication of surface features from a master model to an amorphous metallic article
Johnson, William L.; Bakke, Eric; Peker, Atakan
1999-01-01
The surface features of an article are replicated by preparing a master model having a preselected surface feature thereon which is to be replicated, and replicating the preselected surface feature of the master model. The replication is accomplished by providing a piece of a bulk-solidifying amorphous metallic alloy, contacting the piece of the bulk-solidifying amorphous metallic alloy to the surface of the master model at an elevated replication temperature to transfer a negative copy of the preselected surface feature of the master model to the piece, and separating the piece having the negative copy of the preselected surface feature from the master model.
We have developed a coupled land-surface and dry deposition model for realistic treatment of surface fluxes of heat, moisture, and chemical dry deposition within a comprehensive air quality modeling system. A new land-surface model (LSM) with explicit treatment of soil moisture...
NASA Astrophysics Data System (ADS)
Vaglio-Gaudard, C.; Stoll, K.; Ravaux, S.; Lemaire, M.; Colombier, A. C.; Hudelot, J. P.; Bernard, D.; Amharrak, H.; Di Salvo, J.; Gruel, A.
2014-02-01
An experiment named AMMON is dedicated to the analysis of the neutron and photon physics of the Jules Horowitz Reactor (JHR). AMMON, performed in the EOLE zero-power experimental reactor at CEA Cadarache, is finished since April 2013. Photon heating measurements were performed with both Thermoluminescent Dosimeters (TLD-400s) and Optically-Stimulated Dosimeters (OSLDs) in three AMMON configurations. The objective is to provide data for the experimental validation of the JHR photon calculation tool. The first analysis of the photon heating measurements of the reference configuration (AMMON/REF) is presented in this paper. The reference configuration consists of an experimental zone of 7 JHR assemblies with U3Si2 - Al 27% 235U enriched fuel curved plates surrounded by a driver zone with 623 standard PWR UOx fuel pins. The photon heating has been measured in the aluminum follower of the central and peripheral assemblies, and in aluminum fillers in the rack between assemblies. The measurement analysis is based on Monte Carlo TRIPOLI-4 ® version 8.1 calculations modeling the core exact three-dimensional geometry. The JEFF nuclear data library is used for the calculation of the neutron transport and the photon emission in the AMMON/REF experiment. The photon transport is made on the basis of the EPDL97 photo-atomic library. The prompt and delayed doses deposited in dosimeters have been estimated separately. The transport of 4 (neutrons, photons, electrons and positrons) or 3 particles (photons, electrons and positrons) is simulated in the calculations for the AMMON/REF analysis, depending whether the prompt or delayed dose is calculated. The TRIPOLI-4.8.1 ® calculations makes it possible the modeling of the electromagnetic cascade shower with both electrons and positrons. The delayed dose represents about 25% of the total photon energy deposition in the dosimeters. The comparison between Calculation and Experiment brings into relief a slight systematic underestimation of the calculated global photon energy deposition: (C - E)/E = - 8% ±4.5% (1σ). A special care has been directed towards the determination of the uncertainty associated with the (C-E)/E values. The slight underestimation could be probably explained by an underestimation in the photon emission with the JEFF library.
Birth of the science of immunology.
Schmalstieg, Frank C; Goldman, Armond S
2010-05-01
The science of immunology emerged in the last of the 19th and the first of the 20th century. Substantial progress in physics, chemistry and microbiology was essential for its development. Indeed, microorganisms became one of the principal investigative tools of the major founders of that science - Louis Pasteur, Robert Koch, Ilya Ilich Metchnikoff, Paul Ehrlich and Jules Bordet. It is pertinent that these pioneering scientists were born when questioning and exploration were encouraged because of the legacies of the previous century of enlightenment. Mentors greatly aided their development. Their discoveries were shaped by their individual personalities. In turn they developed other contributors to the nascent field. Their discoveries included the types of leukocytes, the roles of neutrophils in inflammation and defence, cellular lysis due to complement, the principles of humoral and cellular immunology, passive and active immunization, tissue antigens, anaphylaxis, anaphylactoid reactions and autoimmunity. Their work formed the basis of modern immunology that developed many decades later. Immunology has enormously impacted our understanding of the pathogenesis, diagnosis and treatment of infections, immune-mediated disorders and inflammation. Burgeoning advances forecast further important clinical applications of immunology. Yet, their applications will be problematic because few physicians sufficiently understand the science. We propose that understanding modern immunology requires a grasp of how that science developed - who made the discoveries, how they were made, their successes and failures, their interactions and debates all reveal the foundation of modern immunology.
Han, Young Keun; Miller, Kevin M
2009-08-01
To compare vacuum rise time, vacuum limit accuracy, and occlusion break surge of 3 new phacoemulsification machines. Jules Stein Eye Institute and Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, California, USA. The vacuum rise time under normal and enhanced aspiration modes, vacuum limit accuracy, and occlusion break surge of the Infiniti Vision System, Stellaris Vision Enhancement System, and WhiteStar Signature Phacoemulsification System were tested. Vacuum rise time and limit accuracy were measured at limit settings of 400 mm Hg and 600 mm Hg. Surge area was recorded at vacuum limit settings of 200 mm Hg, 300 mm Hg, 400 mm Hg, and 500 mm Hg. The Infiniti had the fastest vacuum rise times under normal and enhanced aspiration modes. At 4 seconds, the vacuum limit accuracy was greatest with the Infiniti at the 400 mm Hg limit and the Signature at the 600 mm Hg limit. The Stellaris did not reach either vacuum target. The Infiniti performed better than the other 2 machines during testing of occlusion break surge at all vacuum limit settings above 200 mm Hg. Under controlled laboratory test conditions, the Infiniti had the fastest vacuum rise time, greatest vacuum limit accuracy at 400 mm Hg, and least occlusion break surge. These results can be explained by the lower compliance of the Infiniti system.
Broussolle, E; Poirier, J; Clarac, F; Barbara, J-G
2012-04-01
We present a short historical review of the major figures, their administrative functions and their works that contributed to make Paris a renowned centre of physiology and neurology during the xixth and the first half of the xxth century. We purposely chose to focus on the period 1800-1950, as 1800 corresponds to the actual beginning of neurosciences, and 1950 marks their exponential rise. Our presentation is divided into four chapters, matching the main disciplines which have progressed and contributed the most to the knowledge we have of the brain sciences: anatomy, physiology, neurology, and psychiatry-psychology. The present article is the third of four parts of this review, and deals with neurology. A special credit should be given to Jean-Martin Charcot who founded the Salpêtrière School of neurology and became one of the world's most important neurologists of the xixth century. We provide below the biographical sketches of Armand Trousseau, Guillaume Benjamin Amand Duchenne, Jean-Martin Charcot, Alfred Vulpian, Désiré-Magloire Bourneville, Paul Richer, Henri Parinaud, Albert Pitres, Jules Joseph Dejerine, Mrs. Augusta Dejerine-Klumpke, Édouard Brissaud, Pierre Marie, Georges Édouard Brutus Gilles de la Tourette, Joseph Babinski, André Thomas, Georges Marinesco, Achille Alexandre Souques, Georges Guillain and Charles Foix. Copyright © 2012 Elsevier Masson SAS. All rights reserved.
The GNC Measurement System for the Automated Transfer Vehicle
NASA Astrophysics Data System (ADS)
Roux, Y.; da Cunha, P.
The Automated Transfer Vehicle (ATV) is a European Space Agency (ESA) funded spacecraft developed by EADS Space Transportation as prime contractor for the space segment together with major European industrial partners, in the frame of the International Space Station (ISS). Its mission objective is threefold : to supply the station with fret and propellant, to reboost ISS to a higher orbit and to dispose of waste from the station. The ATV first flight, called Jules Verne and planned on 2005, will be the first European Vehicle to perform an orbital rendezvous. The GNC Measurement System (GMS) is the ATV on board function in charge of the measurement data collection and preconditioning for the navigation, guidance and control (GNC) algorithms. The GMS is made up of hardware which are the navigation sensors (with a certain level of hardware redundancy for each of them), and of an on-board software that manages, monitors and performs consistency checks to detect and isolate potential sensor failures. The GMS relies on six kinds of navigation sensors, used during various phases of the mission : the gyrometers assembly (GYRA), the accelerometers assembly (ACCA), the star trackers (STR), the GPS receivers, the telegoniometers (TGM) and the videometers (VDM), the last two being used for the final rendezvous phase. The GMS function is developed by EADS Space Transportation together with other industrial partners: EADS Astrium, EADS Sodern, Laben and Dasa Jena Optronik.
[A review on research of land surface water and heat fluxes].
Sun, Rui; Liu, Changming
2003-03-01
Many field experiments were done, and soil-vegetation-atmosphere transfer(SVAT) models were stablished to estimate land surface heat fluxes. In this paper, the processes of experimental research on land surface water and heat fluxes are reviewed, and three kinds of SVAT model(single layer model, two layer model and multi-layer model) are analyzed. Remote sensing data are widely used to estimate land surface heat fluxes. Based on remote sensing and energy balance equation, different models such as simplified model, single layer model, extra resistance model, crop water stress index model and two source resistance model are developed to estimate land surface heat fluxes and evapotranspiration. These models are also analyzed in this paper.
Portable document format file showing the surface models of cadaver whole body.
Shin, Dong Sun; Chung, Min Suk; Park, Jin Seo; Park, Hyung Seon; Lee, Sangho; Moon, Young Lae; Jang, Hae Gwon
2012-08-01
In the Visible Korean project, 642 three-dimensional (3D) surface models have been built from the sectioned images of a male cadaver. It was recently discovered that popular PDF file enables users to approach the numerous surface models conveniently on Adobe Reader. Purpose of this study was to present a PDF file including systematized surface models of human body as the beneficial contents. To achieve the purpose, fitting software packages were employed in accordance with the procedures. Two-dimensional (2D) surface models including the original sectioned images were embedded into the 3D surface models. The surface models were categorized into systems and then groups. The adjusted surface models were inserted to a PDF file, where relevant multimedia data were added. The finalized PDF file containing comprehensive data of a whole body could be explored in varying manners. The PDF file, downloadable freely from the homepage (http://anatomy.co.kr), is expected to be used as a satisfactory self-learning tool of anatomy. Raw data of the surface models can be extracted from the PDF file and employed for various simulations for clinical practice. The technique to organize the surface models will be applied to manufacture of other PDF files containing various multimedia contents.
FacetModeller: Software for manual creation, manipulation and analysis of 3D surface-based models
NASA Astrophysics Data System (ADS)
Lelièvre, Peter G.; Carter-McAuslan, Angela E.; Dunham, Michael W.; Jones, Drew J.; Nalepa, Mariella; Squires, Chelsea L.; Tycholiz, Cassandra J.; Vallée, Marc A.; Farquharson, Colin G.
2018-01-01
The creation of 3D models is commonplace in many disciplines. Models are often built from a collection of tessellated surfaces. To apply numerical methods to such models it is often necessary to generate a mesh of space-filling elements that conforms to the model surfaces. While there are meshing algorithms that can do so, they place restrictive requirements on the surface-based models that are rarely met by existing 3D model building software. Hence, we have developed a Java application named FacetModeller, designed for efficient manual creation, modification and analysis of 3D surface-based models destined for use in numerical modelling.
NASA Technical Reports Server (NTRS)
Lee, S. S.; Nwadike, E. V.; Sinha, S. E.
1982-01-01
The theory of a three dimensional (3-D) mathematical thermal discharge model and a related one dimensional (1-D) model are described. Model verification at two sites, a separate user's manual for each model are included. The 3-D model has two forms: free surface and rigid lid. The former allows a free air/water interface and is suited for significant surface wave heights compared to mean water depth, estuaries and coastal regions. The latter is suited for small surface wave heights compared to depth because surface elevation was removed as a parameter. These models allow computation of time dependent velocity and temperature fields for given initial conditions and time-varying boundary conditions. The free surface model also provides surface height variations with time.
NASA Astrophysics Data System (ADS)
Hendriks, D.; Ball, S. M.; Van der Wegen, M.; Verkaik, J.; van Dam, A.
2016-12-01
We present a coupled groundwater-surface water model for the San Francisco Bay and Sacramento Valley that consists of a combination of a spatially-distributed groundwater model (Modflow) based on the USGS Central Valley model(1) and the Flexible Mesh (FM) surface water model of the Bay Area(2). With this coupled groundwater-surface water model, we assessed effects of climate, surface water abstractions and groundwater pumping on surface water and groundwater levels, groundwater-surface water interaction and infiltration/seepage fluxes. Results show that the effect of climate (high flow and low flow) on surface water and groundwater is significant and most prominent in upstream areas. The surface water abstractions cause significant local surface water levels decrease (over 2 m), which may cause inflow of bay water during low flow periods, resulting in salinization of surface water in more upstream areas. Groundwater level drawdown due to surface water withdrawal is moderate and limited to the area of the withdrawals. The groundwater pumping causes large groundwater level drawdowns (up to 0.8 m) and significant changes in seepage/infiltration fluxes in the model. However, the effect on groundwater-surface water exchange is relatively small. The presented model instrument gives a sound first impression of the effects of climate and water abstraction on both surface water and groundwater. The combination of Modflow and Flexible Mesh has potential for modelling of groundwater-surface water exchange in deltaic areas, also in other parts of the world. However, various improvements need to be made in order to make the simulation results useful in practice. In addition, a water quality aspect could be added to assess salinization processes as well as groundwater-surface water aspects of water and soil pollution. (1) http://ca.water.usgs.gov/projects/central-valley/central-valley-hydrologic-model.html (2) www.d3d-baydelta.org
Space environment and lunar surface processes
NASA Technical Reports Server (NTRS)
Comstock, G. M.
1979-01-01
The development of a general rock/soil model capable of simulating in a self consistent manner the mechanical and exposure history of an assemblage of solid and loose material from submicron to planetary size scales, applicable to lunar and other space exposed planetary surfaces is discussed. The model was incorporated into a computer code called MESS.2 (model for the evolution of space exposed surfaces). MESS.2, which represents a considerable increase in sophistication and scope over previous soil and rock surface models, is described. The capabilities of previous models for near surface soil and rock surfaces are compared with the rock/soil model, MESS.2.
Measurement of deformations of models in a wind tunnel
NASA Astrophysics Data System (ADS)
Charpin, F.; Armand, C.; Selvaggini, R.
Techniques used at the ONERA Modane Center to monitor geometric variations in scale-models in wind tunnel trials are described. The methods include: photography of reflections from mirrors embedded in the model surface; laser-based torsiometry with polarized mirrors embedded in the model surface; predictions of the deformations using numerical codes for the model surface mechanical characteristics and the measured surface stresses; and, use of an optical detector to monitor the position of luminous fiber optic sources emitting from the model surfaces. The data enhance the confidence that the wind tunnel aerodynamic data will correspond with the in-flight performance of full scale flight surfaces.
Modeling wind adjustment factor and midflame wind speed for Rothermel's surface fire spread model
Patricia L. Andrews
2012-01-01
Rothermel's surface fire spread model was developed to use a value for the wind speed that affects surface fire, called midflame wind speed. Models have been developed to adjust 20-ft wind speed to midflame wind speed for sheltered and unsheltered surface fuel. In this report, Wind Adjustment Factor (WAF) model equations are given, and the BehavePlus fire modeling...
Characterization, modeling and simulation of fused deposition modeling fabricated part surfaces
NASA Astrophysics Data System (ADS)
Taufik, Mohammad; Jain, Prashant K.
2017-12-01
Surface roughness is generally used for characterization, modeling and simulation of fused deposition modeling (FDM) fabricated part surfaces. But the average surface roughness is not able to provide the insight of surface characteristics with sharp peaks and deep valleys. It deals in the average sense for all types of surfaces, including FDM fabricated surfaces with distinct surface profile features. The present research work shows that kurtosis and skewness can be used for characterization, modeling and simulation of FDM surfaces because these roughness parameters have the ability to characterize a surface with sharp peaks and deep valleys. It can be critical in certain application areas in tribology and biomedicine, where the surface profile plays an important role. Thus, in this study along with surface roughness, skewness and kurtosis are considered to show a novel strategy to provide new transferable knowledge about FDM fabricated part surfaces. The results suggest that the surface roughness, skewness and kurtosis are significantly different at 0° and in the range (0°, 30°], [30°, 90°] of build orientation.
Kubiak-Ossowska, Karina; Mulheran, Paul A; Nowak, Wieslaw
2014-08-21
The mechanism of human fibronectin adhesion synergy region (known as integrin binding region) in repeat 9 (FN(III)9) domain adsorption at pH 7 onto various and contrasting model surfaces has been studied using atomistic molecular dynamics simulations. We use an ionic model to mimic mica surface charge density but without a long-range electric field above the surface, a silica model with a long-range electric field similar to that found experimentally, and an Au {111} model with no partial charges or electric field. A detailed description of the adsorption processes and the contrasts between the various model surfaces is provided. In the case of our model silica surface with a long-range electrostatic field, the adsorption is rapid and primarily driven by electrostatics. Because it is negatively charged (-1e), FN(III)9 readily adsorbs to a positively charged surface. However, due to its partial charge distribution, FN(III)9 can also adsorb to the negatively charged mica model because of the absence of a long-range repulsive electric field. The protein dipole moment dictates its contrasting orientation at these surfaces, and the anchoring residues have opposite charges to the surface. Adsorption on the model Au {111} surface is possible, but less specific, and various protein regions might be involved in the interactions with the surface. Despite strongly influencing the protein mobility, adsorption at these model surfaces does not require wholesale FN(III)9 conformational changes, which suggests that the biological activity of the adsorbed protein might be preserved.
Internal Physical Features of a Land Surface Model Employing a Tangent Linear Model
NASA Technical Reports Server (NTRS)
Yang, Runhua; Cohn, Stephen E.; daSilva, Arlindo; Joiner, Joanna; Houser, Paul R.
1997-01-01
The Earth's land surface, including its biomass, is an integral part of the Earth's weather and climate system. Land surface heterogeneity, such as the type and amount of vegetative covering., has a profound effect on local weather variability and therefore on regional variations of the global climate. Surface conditions affect local weather and climate through a number of mechanisms. First, they determine the re-distribution of the net radiative energy received at the surface, through the atmosphere, from the sun. A certain fraction of this energy increases the surface ground temperature, another warms the near-surface atmosphere, and the rest evaporates surface water, which in turn creates clouds and causes precipitation. Second, they determine how much rainfall and snowmelt can be stored in the soil and how much instead runs off into waterways. Finally, surface conditions influence the near-surface concentration and distribution of greenhouse gases such as carbon dioxide. The processes through which these mechanisms interact with the atmosphere can be modeled mathematically, to within some degree of uncertainty, on the basis of underlying physical principles. Such a land surface model provides predictive capability for surface variables including ground temperature, surface humidity, and soil moisture and temperature. This information is important for agriculture and industry, as well as for addressing fundamental scientific questions concerning global and local climate change. In this study we apply a methodology known as tangent linear modeling to help us understand more deeply, the behavior of the Mosaic land surface model, a model that has been developed over the past several years at NASA/GSFC. This methodology allows us to examine, directly and quantitatively, the dependence of prediction errors in land surface variables upon different vegetation conditions. The work also highlights the importance of accurate soil moisture information. Although surface variables are predicted imperfectly due to inherent uncertainties in the modeling process, our study suggests how satellite observations can be combined with the model, through land surface data assimilation, to improve their prediction.
Modelling hazardous surface hoar layers in the mountain snowpack over space and time
NASA Astrophysics Data System (ADS)
Horton, Simon Earl
Surface hoar layers are a common failure layer in hazardous snow slab avalanches. Surface hoar crystals (frost) initially form on the surface of the snow, and once buried can remain a persistent weak layer for weeks or months. Avalanche forecasters have difficulty tracking the spatial distribution and mechanical properties of these layers in mountainous terrain. This thesis presents numerical models and remote sensing methods to track the distribution and properties of surface hoar layers over space and time. The formation of surface hoar was modelled with meteorological data by calculating the downward flux of water vapour from the atmospheric boundary layer. The timing of surface hoar formation and the modelled crystal size was verified at snow study sites throughout western Canada. The major surface hoar layers over several winters were predicted with fair success. Surface hoar formation was modelled over various spatial scales using meteorological data from weather forecast models. The largest surface hoar crystals formed in regions and elevation bands with clear skies, warm and humid air, cold snow surfaces, and light winds. Field surveys measured similar regional-scale patterns in surface hoar distribution. Surface hoar formation patterns on different slope aspects were observed, but were not modelled reliably. Mechanical field tests on buried surface hoar layers found layers increased in shear strength over time, but had persistent high propensity for fracture propagation. Layers with large crystals and layers overlying hard melt-freeze crusts showed greater signs of instability. Buried surface hoar layers were simulated with the snow cover model SNOWPACK and verified with avalanche observations, finding most hazardous surface hoar layers were identified with a structural stability index. Finally, the optical properties of surface hoar crystals were measured in the field with spectral instruments. Large plate-shaped crystals were less reflective at shortwave infrared wavelengths than other common surface snow grains. The methods presented in this thesis were developed into operational products that model hazardous surface hoar layers in western Canada. Further research and refinements could improve avalanche forecasts in regions prone to hazardous surface hoar layers.
UNAVCO Software and Services for Visualization and Exploration of Geoscience Data
NASA Astrophysics Data System (ADS)
Meertens, C.; Wier, S.
2007-12-01
UNAVCO has been involved in visualization of geoscience data to support education and research for several years. An early and ongoing service is the Jules Verne Voyager, a web browser applet built on the GMT that displays any area on Earth, with many data set choices, including maps, satellite images, topography, geoid heights, sea-floor ages, strain rates, political boundaries, rivers and lakes, earthquake and volcano locations, focal mechanisms, stress axes, and observed and modeled plate motion and deformation velocity vectors from geodetic measurements around the world. As part of the GEON project, UNAVCO has developed the GEON IDV, a research-level, 4D (earth location, depth and/or altitude, and time), Java application for interactive display and analysis of geoscience data. The GEON IDV is designed to meet the challenge of investigating complex, multi-variate, time-varying, three-dimensional geoscience data anywhere on earth. The GEON IDV supports simultaneous displays of data sets from differing sources, with complete control over colors, time animation, map projection, map area, point of view, and vertical scale. The GEON IDV displays gridded and point data, images, GIS shape files, and several other types of data. The GEON IDV has symbols and displays for GPS velocity vectors, seismic tomography, earthquake focal mechanisms, earthquake locations with magnitude or depth, seismic ray paths in 3D, seismic anisotropy, convection model visualization, earth strain axes and strain field imagery, and high-resolution 3D topographic relief maps. Multiple data sources and display types may appear in one view. As an example of GEON IDV utility, it can display hypocenters under a volcano, a surface geology map of the volcano draped over 3D topographic relief, town locations and political boundaries, and real-time 3D weather radar clouds of volcanic ash in the atmosphere, with time animation. The GEON IDV can drive a GeoWall or other 3D stereo system. IDV output includes imagery, movies, and KML files for Google Earth use of IDV static images, where Google Earth can handle the display. The IDV can be scripted to create display images on user request or automatically on data arrival, offering the use of the IDV as a back end to support a data web site. We plan to extend the power of the IDV by accepting new data types and data services, such as GeoSciML. An active program of online and video training in GEON IDV use is planned. UNAVCO will support users who need assistance converting their data to the standard formats used by the GEON IDV. The UNAVCO Facility provides web-accessible support for Google Earth and Google Maps display of any of more than 9500 GPS stations and survey points, including metadata for each installation. UNAVCO provides corresponding Open Geospatial Consortium (OGC) web services with the same data. UNAVCO's goal is to facilitate data access, interoperability, and efficient searches, exploration, and use of data by promoting web services, standards for GEON IDV data formats and metadata, and software able to simultaneously read and display multiple data sources, formats, and map locations or projections. Retention and propagation of semantics and metadata with observational and experimental values is essential for interoperability and understanding diverse data sources.
Further Investigations of Gravity Modeling on Surface-Interacting Vehicle Simulations
NASA Technical Reports Server (NTRS)
Madden, Michael M.
2009-01-01
A vehicle simulation is "surface-interacting" if the state of the vehicle (position, velocity, and acceleration) relative to the surface is important. Surface-interacting simulations perform ascent, entry, descent, landing, surface travel, or atmospheric flight. The dynamics of surface-interacting simulations are influenced by the modeling of gravity. Gravity is the sum of gravitation and the centrifugal acceleration due to the world s rotation. Both components are functions of position relative to the world s center and that position for a given set of geodetic coordinates (latitude, longitude, and altitude) depends on the world model (world shape and dynamics). Thus, gravity fidelity depends on the fidelities of the gravitation model and the world model and on the interaction of the gravitation and world model. A surface-interacting simulation cannot treat the gravitation separately from the world model. This paper examines the actual performance of different pairs of world and gravitation models (or direct gravity models) on the travel of a subsonic civil transport in level flight under various starting conditions.
Gravity Modeling Effects on Surface-Interacting Vehicles in Supersonic Flight
NASA Technical Reports Server (NTRS)
Madden, Michael M.
2010-01-01
A vehicle simulation is "surface-interacting" if the state of the vehicle (position, velocity, and acceleration) relative to the surface is important. Surface-interacting simulations per-form ascent, entry, descent, landing, surface travel, or atmospheric flight. The dynamics of surface-interacting simulations are influenced by the modeling of gravity. Gravity is the sum of gravitation and the centrifugal acceleration due to the world s rotation. Both components are functions of position relative to the world s center and that position for a given set of geodetic coordinates (latitude, longitude, and altitude) depends on the world model (world shape and dynamics). Thus, gravity fidelity depends on the fidelities of the gravitation model and the world model and on the interaction of these two models. A surface-interacting simulation cannot treat gravitation separately from the world model. This paper examines the actual performance of different pairs of world and gravitation models (or direct gravity models) on the travel of a supersonic aircraft in level flight under various start-ing conditions.
Land-Atmosphere Coupling in the Multi-Scale Modelling Framework
NASA Astrophysics Data System (ADS)
Kraus, P. M.; Denning, S.
2015-12-01
The Multi-Scale Modeling Framework (MMF), in which cloud-resolving models (CRMs) are embedded within general circulation model (GCM) gridcells to serve as the model's cloud parameterization, has offered a number of benefits to GCM simulations. The coupling of these cloud-resolving models directly to land surface model instances, rather than passing averaged atmospheric variables to a single instance of a land surface model, the logical next step in model development, has recently been accomplished. This new configuration offers conspicuous improvements to estimates of precipitation and canopy through-fall, but overall the model exhibits warm surface temperature biases and low productivity.This work presents modifications to a land-surface model that take advantage of the new multi-scale modeling framework, and accommodate the change in spatial scale from a typical GCM range of ~200 km to the CRM grid-scale of 4 km.A parameterization is introduced to apportion modeled surface radiation into direct-beam and diffuse components. The diffuse component is then distributed among the land-surface model instances within each GCM cell domain. This substantially reduces the number excessively low light values provided to the land-surface model when cloudy conditions are modeled in the CRM, associated with its 1-D radiation scheme. The small spatial scale of the CRM, ~4 km, as compared with the typical ~200 km GCM scale, provides much more realistic estimates of precipitation intensity, this permits the elimination of a model parameterization of canopy through-fall. However, runoff at such scales can no longer be considered as an immediate flow to the ocean. Allowing sub-surface water flow between land-surface instances within the GCM domain affords better realism and also reduces temperature and productivity biases.The MMF affords a number of opportunities to land-surface modelers, providing both the advantages of direct simulation at the 4 km scale and a much reduced conceptual gap between model resolution and parameterized processes.
A new class of actuator surface models for wind turbines
NASA Astrophysics Data System (ADS)
Yang, Xiaolei; Sotiropoulos, Fotis
2018-05-01
Actuator line model has been widely employed in wind turbine simulations. However, the standard actuator line model does not include a model for the turbine nacelle which can significantly impact turbine wake characteristics as shown in the literature. Another disadvantage of the standard actuator line model is that more geometrical features of turbine blades cannot be resolved on a finer mesh. To alleviate these disadvantages of the standard model, we develop a new class of actuator surface models for turbine blades and nacelle to take into account more geometrical details of turbine blades and include the effect of turbine nacelle. In the actuator surface model for blade, the aerodynamic forces calculated using the blade element method are distributed from the surface formed by the foil chords at different radial locations. In the actuator surface model for nacelle, the forces are distributed from the actual nacelle surface with the normal force component computed in the same way as in the direct forcing immersed boundary method and the tangential force component computed using a friction coefficient and a reference velocity of the incoming flow. The actuator surface model for nacelle is evaluated by simulating the flow over periodically placed nacelles. Both the actuator surface simulation and the wall-resolved large-eddy simulation are carried out. The comparison shows that the actuator surface model is able to give acceptable results especially at far wake locations on a very coarse mesh. It is noted that although this model is employed for the turbine nacelle in this work, it is also applicable to other bluff bodies. The capability of the actuator surface model in predicting turbine wakes is assessed by simulating the flow over the MEXICO (Model experiments in Controlled Conditions) turbine and a hydrokinetic turbine.
Lambeth, Christopher; Amatoury, Jason; Wang, Ziyu; Foster, Sheryl; Amis, Terence; Kairaitis, Kristina
2017-03-01
Macroscopic pharyngeal anatomical abnormalities are thought to contribute to the pathogenesis of upper airway (UA) obstruction in obstructive sleep apnea (OSA). Microscopic changes in the UA mucosal lining of OSA subjects are reported; however, the impact of these changes on UA mucosal surface topography is unknown. This study aimed to 1 ) develop methodology to measure UA mucosal surface topography, and 2 ) compare findings from healthy and OSA subjects. Ten healthy and eleven OSA subjects were studied. Awake, gated (end expiration), head and neck position controlled magnetic resonance images (MRIs) of the velopharynx (VP) were obtained. VP mucosal surfaces were segmented from axial images, and three-dimensional VP mucosal surface models were constructed. Curvature analysis of the models was used to study the VP mucosal surface topography. Principal, mean, and Gaussian curvatures were used to define surface shape composition and surface roughness of the VP mucosal surface models. Significant differences were found in the surface shape composition, with more saddle/spherical and less flat/cylindrical shapes in OSA than healthy VP mucosal surface models ( P < 0.01). OSA VP mucosal surface models were also found to have more mucosal surface roughness ( P < 0.0001) than healthy VP mucosal surface models. Our novel methodology was utilized to model the VP mucosal surface of OSA and healthy subjects. OSA subjects were found to have different VP mucosal surface topography, composed of increased irregular shapes and increased roughness. We speculate increased irregularity in VP mucosal surface may increase pharyngeal collapsibility as a consequence of friction-related pressure loss. NEW & NOTEWORTHY A new methodology was used to model the upper airway mucosal surface topography from magnetic resonance images of patients with obstructive sleep apnea and healthy adults. Curvature analysis was used to analyze the topography of the models, and a new metric was derived to describe the mucosal surface roughness. Increased roughness was found in the obstructive sleep apnea vs. healthy group, but further research is required to determine the functional effects of the measured difference on upper airway airflow mechanics. Copyright © 2017 the American Physiological Society.
Climatic Models Ensemble-based Mid-21st Century Runoff Projections: A Bayesian Framework
NASA Astrophysics Data System (ADS)
Achieng, K. O.; Zhu, J.
2017-12-01
There are a number of North American Regional Climate Change Assessment Program (NARCCAP) climatic models that have been used to project surface runoff in the mid-21st century. Statistical model selection techniques are often used to select the model that best fits data. However, model selection techniques often lead to different conclusions. In this study, ten models are averaged in Bayesian paradigm to project runoff. Bayesian Model Averaging (BMA) is used to project and identify effect of model uncertainty on future runoff projections. Baseflow separation - a two-digital filter which is also called Eckhardt filter - is used to separate USGS streamflow (total runoff) into two components: baseflow and surface runoff. We use this surface runoff as the a priori runoff when conducting BMA of runoff simulated from the ten RCM models. The primary objective of this study is to evaluate how well RCM multi-model ensembles simulate surface runoff, in a Bayesian framework. Specifically, we investigate and discuss the following questions: How well do ten RCM models ensemble jointly simulate surface runoff by averaging over all the models using BMA, given a priori surface runoff? What are the effects of model uncertainty on surface runoff simulation?
Model-based conifer crown surface reconstruction from multi-ocular high-resolution aerial imagery
NASA Astrophysics Data System (ADS)
Sheng, Yongwei
2000-12-01
Tree crown parameters such as width, height, shape and crown closure are desirable in forestry and ecological studies, but they are time-consuming and labor intensive to measure in the field. The stereoscopic capability of high-resolution aerial imagery provides a way to crown surface reconstruction. Existing photogrammetric algorithms designed to map terrain surfaces, however, cannot adequately extract crown surfaces, especially for steep conifer crowns. Considering crown surface reconstruction in a broader context of tree characterization from aerial images, we develop a rigorous perspective tree image formation model to bridge image-based tree extraction and crown surface reconstruction, and an integrated model-based approach to conifer crown surface reconstruction. Based on the fact that most conifer crowns are in a solid geometric form, conifer crowns are modeled as a generalized hemi-ellipsoid. Both the automatic and semi-automatic approaches are investigated to optimal tree model development from multi-ocular images. The semi-automatic 3D tree interpreter developed in this thesis is able to efficiently extract reliable tree parameters and tree models in complicated tree stands. This thesis starts with a sophisticated stereo matching algorithm, and incorporates tree models to guide stereo matching. The following critical problems are addressed in the model-based surface reconstruction process: (1) the problem of surface model composition from tree models, (2) the occlusion problem in disparity prediction from tree models, (3) the problem of integrating the predicted disparities into image matching, (4) the tree model edge effect reduction on the disparity map, (5) the occlusion problem in orthophoto production, and (6) the foreshortening problem in image matching, which is very serious for conifer crown surfaces. Solutions to the above problems are necessary for successful crown surface reconstruction. The model-based approach was applied to recover the canopy surface of a dense redwood stand using tri-ocular high-resolution images scanned from 1:2,400 aerial photographs. The results demonstrate the approach's ability to reconstruct complicated stands. The model-based approach proposed in this thesis is potentially applicable to other surfaces recovering problems with a priori knowledge about objects.
A solution to the surface intersection problem. [Boolean functions in geometric modeling
NASA Technical Reports Server (NTRS)
Timer, H. G.
1977-01-01
An application-independent geometric model within a data base framework should support the use of Boolean operators which allow the user to construct a complex model by appropriately combining a series of simple models. The use of these operators leads to the concept of implicitly and explicitly defined surfaces. With an explicitly defined model, the surface area may be computed by simply summing the surface areas of the bounding surfaces. For an implicitly defined model, the surface area computation must deal with active and inactive regions. Because the surface intersection problem involves four unknowns and its solution is a space curve, the parametric coordinates of each surface must be determined as a function of the arc length. Various subproblems involved in the general intersection problem are discussed, and the mathematical basis for their solution is presented along with a program written in FORTRAN IV for implementation on the IBM 370 TSO system.
A coarse grain model for protein-surface interactions
NASA Astrophysics Data System (ADS)
Wei, Shuai; Knotts, Thomas A.
2013-09-01
The interaction of proteins with surfaces is important in numerous applications in many fields—such as biotechnology, proteomics, sensors, and medicine—but fundamental understanding of how protein stability and structure are affected by surfaces remains incomplete. Over the last several years, molecular simulation using coarse grain models has yielded significant insights, but the formalisms used to represent the surface interactions have been rudimentary. We present a new model for protein surface interactions that incorporates the chemical specificity of both the surface and the residues comprising the protein in the context of a one-bead-per-residue, coarse grain approach that maintains computational efficiency. The model is parameterized against experimental adsorption energies for multiple model peptides on different types of surfaces. The validity of the model is established by its ability to quantitatively and qualitatively predict the free energy of adsorption and structural changes for multiple biologically-relevant proteins on different surfaces. The validation, done with proteins not used in parameterization, shows that the model produces remarkable agreement between simulation and experiment.
A diffuse radar scattering model from Martian surface rocks
NASA Technical Reports Server (NTRS)
Calvin, W. M.; Jakosky, B. M.; Christensen, P. R.
1987-01-01
Remote sensing of Mars has been done with a variety of instrumentation at various wavelengths. Many of these data sets can be reconciled with a surface model of bonded fines (or duricrust) which varies widely across the surface and a surface rock distribution which varies less so. A surface rock distribution map from -60 to +60 deg latitude has been generated by Christensen. Our objective is to model the diffuse component of radar reflection based on this surface distribution of rocks. The diffuse, rather than specular, scattering is modeled because the diffuse component arises due to scattering from rocks with sizes on the order of the wavelength of the radar beam. Scattering for radio waves of 12.5 cm is then indicative of the meter scale and smaller structure of the surface. The specular term is indicative of large scale surface undulations and should not be causally related to other surface physical properties. A simplified model of diffuse scattering is described along with two rock distribution models. The results of applying the models to a planet of uniform fractional rock coverage with values ranging from 5 to 20% are discussed.
Land Surface Microwave Emissivity Dynamics: Observations, Analysis and Modeling
NASA Technical Reports Server (NTRS)
Tian, Yudong; Peters-Lidard, Christa D.; Harrison, Kenneth W.; Kumar, Sujay; Ringerud, Sarah
2014-01-01
Land surface microwave emissivity affects remote sensing of both the atmosphere and the land surface. The dynamical behavior of microwave emissivity over a very diverse sample of land surface types is studied. With seven years of satellite measurements from AMSR-E, we identified various dynamical regimes of the land surface emission. In addition, we used two radiative transfer models (RTMs), the Community Radiative Transfer Model (CRTM) and the Community Microwave Emission Modeling Platform (CMEM), to simulate land surface emissivity dynamics. With both CRTM and CMEM coupled to NASA's Land Information System, global-scale land surface microwave emissivities were simulated for five years, and evaluated against AMSR-E observations. It is found that both models have successes and failures over various types of land surfaces. Among them, the desert shows the most consistent underestimates (by approx. 70-80%), due to limitations of the physical models used, and requires a revision in both systems. Other snow-free surface types exhibit various degrees of success and it is expected that parameter tuning can improve their performances.
RIPPLE - A new model for incompressible flows with free surfaces
NASA Technical Reports Server (NTRS)
Kothe, D. B.; Mjolsness, R. C.
1991-01-01
A new free surface flow model, RIPPLE, is summarized. RIPPLE obtains finite difference solutions for incompressible flow problems having strong surface tension forces at free surfaces of arbitrarily complex topology. The key innovation is the continuum surface force model which represents surface tension as a (strongly) localized volume force. Other features include a higher-order momentum advection model, a volume-of-fluid free surface treatment, and an efficient two-step projection solution method. RIPPLE's unique capabilities are illustrated with two example problems: low-gravity jet-induced tank flow, and the collision and coalescence of two cylindrical rods.
Joint surface modeling with thin-plate splines.
Boyd, S K; Ronsky, J L; Lichti, D D; Salkauskas, K; Chapman, M A; Salkauskas, D
1999-10-01
Mathematical joint surface models based on experimentally determined data points can be used to investigate joint characteristics such as curvature, congruency, cartilage thickness, joint contact areas, as well as to provide geometric information well suited for finite element analysis. Commonly, surface modeling methods are based on B-splines, which involve tensor products. These methods have had success; however, they are limited due to the complex organizational aspect of working with surface patches, and modeling unordered, scattered experimental data points. An alternative method for mathematical joint surface modeling is presented based on the thin-plate spline (TPS). It has the advantage that it does not involve surface patches, and can model scattered data points without experimental data preparation. An analytical surface was developed and modeled with the TPS to quantify its interpolating and smoothing characteristics. Some limitations of the TPS include discontinuity of curvature at exactly the experimental surface data points, and numerical problems dealing with data sets in excess of 2000 points. However, suggestions for overcoming these limitations are presented. Testing the TPS with real experimental data, the patellofemoral joint of a cat was measured with multistation digital photogrammetry and modeled using the TPS to determine cartilage thicknesses and surface curvature. The cartilage thickness distribution ranged between 100 to 550 microns on the patella, and 100 to 300 microns on the femur. It was found that the TPS was an effective tool for modeling joint surfaces because no preparation of the experimental data points was necessary, and the resulting unique function representing the entire surface does not involve surface patches. A detailed algorithm is presented for implementation of the TPS.
NASA Technical Reports Server (NTRS)
Lee, S. S.; Sengupta, S.; Nwadike, E. V.; Sinha, S. K.
1982-01-01
The six-volume report: describes the theory of a three dimensional (3-D) mathematical thermal discharge model and a related one dimensional (1-D) model, includes model verification at two sites, and provides a separate user's manual for each model. The 3-D model has two forms: free surface and rigid lid. The former, verified at Anclote Anchorage (FL), allows a free air/water interface and is suited for significant surface wave heights compared to mean water depth; e.g., estuaries and coastal regions. The latter, verified at Lake Keowee (SC), is suited for small surface wave heights compared to depth (e.g., natural or man-made inland lakes) because surface elevation has been removed as a parameter. These models allow computation of time-dependent velocity and temperature fields for given initial conditions and time-varying boundary conditions. The free-surface model also provides surface height variations with time.
Light radiation pressure upon an optically orthotropic surface
NASA Astrophysics Data System (ADS)
Nerovny, Nikolay A.; Lapina, Irina E.; Grigorjev, Anton S.
2017-11-01
In this paper, we discuss the problem of determination of light radiation pressure force upon an anisotropic surface. The optical parameters of such a surface are considered to have major and minor axes, so the model is called an orthotropic model. We derive the equations for force components from emission, absorption, and reflection, utilizing a modified Maxwell's specular-diffuse model. The proposed model can be used to model a flat solar sail with wrinkles. By performing Bayesian analysis for example of a wrinkled surface, we show that there are cases in which an orthotropic model of the optical parameters of a surface may be more accurate than an isotropic model.
Simulations of surface winds at the Viking Lander sites using a one-level model
NASA Technical Reports Server (NTRS)
Bridger, Alison F. C.; Haberle, Robert M.
1992-01-01
The one-level model developed by Mass and Dempsey for use in predicting surface flows in regions of complex terrain was adapted to simulate surface flows at the Viking lander sites on Mars. In the one-level model, prediction equations for surface winds and temperatures are formulated and solved. Surface temperatures change with time in response to diabatic heating, horizontal advection, adiabatic heating and cooling effects, and horizontal diffusion. Surface winds can change in response to horizontal advection, pressure gradient forces, Coriolis forces, surface drag, and horizontal diffusion. Surface pressures are determined by integration of the hydrostatic equation from the surface to some reference level. The model has successfully simulated surface flows under a variety of conditions in complex-terrain regions on Earth.
A NEW LAND-SURFACE MODEL IN MM5
There has recently been a general realization that more sophisticated modeling of land-surface processes can be important for mesoscale meteorology models. Land-surface models (LSMs) have long been important components in global-scale climate models because of their more compl...
McDonald, Richard; Nelson, Jonathan; Kinzel, Paul; Conaway, Jeffrey S.
2006-01-01
The Multi-Dimensional Surface-Water Modeling System (MD_SWMS) is a Graphical User Interface for surface-water flow and sediment-transport models. The capabilities of MD_SWMS for developing models include: importing raw topography and other ancillary data; building the numerical grid and defining initial and boundary conditions; running simulations; visualizing results; and comparing results with measured data.
Empirical Measurement and Model Validation of Infrared Spectra of Contaminated Surfaces
NASA Astrophysics Data System (ADS)
Archer, Sean
The goal of this thesis was to validate predicted infrared spectra of liquid contaminated surfaces from a micro-scale bi-directional reflectance distribution function (BRDF) model through the use of empirical measurement. Liquid contaminated surfaces generally require more sophisticated radiometric modeling to numerically describe surface properties. The Digital Image and Remote Sensing Image Generation (DIRSIG) model utilizes radiative transfer modeling to generate synthetic imagery for a variety of applications. Aside from DIRSIG, a micro-scale model known as microDIRSIG has been developed as a rigorous ray tracing physics-based model that could predict the BRDF of geometric surfaces that are defined as micron to millimeter resolution facets. The model offers an extension from the conventional BRDF models by allowing contaminants to be added as geometric objects to a micro-facet surface. This model was validated through the use of Fourier transform infrared spectrometer measurements. A total of 18 different substrate and contaminant combinations were measured and compared against modeled outputs. The substrates used in this experiment were wood and aluminum that contained three different paint finishes. The paint finishes included no paint, Krylon ultra-flat black, and Krylon glossy black. A silicon based oil (SF96) was measured out and applied to each surface to create three different contamination cases for each surface. Radiance in the longwave infrared region of the electromagnetic spectrum was measured by a Design and Prototypes (D&P) Fourier transform infrared spectrometer and a Physical Sciences Inc. Adaptive Infrared Imaging Spectroradiometer (AIRIS). The model outputs were compared against the measurements quantitatively in both the emissivity and radiance domains. A temperature emissivity separation (TES) algorithm had to be applied to the measured radiance spectra for comparison with the microDIRSIG predicted emissivity spectra. The model predicted emissivity spectra was also forward modeled through a DIRSIG simulation for comparisons to the radiance measurements. The results showed a promising agreement for homogeneous surfaces with liquid contamination that could be well characterized geometrically. Limitations arose in substrates that were modeled as homogeneous surfaces, but had spatially varying artifacts due to uncertainties with contaminant and surface interactions. There is high desire for accurate physics based modeling of liquid contaminated surfaces and this validation framework may be extended to include a wider array of samples for more realistic natural surfaces that are often found in real world scenarios.
NASA Technical Reports Server (NTRS)
Senocak, I.; Ackerman, A. S.; Kirkpatrick, M. P.; Stevens, D. E.; Mansour, N. N.
2004-01-01
Large-eddy simulation (LES) is a widely used technique in armospheric modeling research. In LES, large, unsteady, three dimensional structures are resolved and small structures that are not resolved on the computational grid are modeled. A filtering operation is applied to distinguish between resolved and unresolved scales. We present two near-surface models that have found use in atmospheric modeling. We also suggest a simpler eddy viscosity model that adopts Prandtl's mixing length model (Prandtl 1925) in the vicinity of the surface and blends with the dynamic Smagotinsky model (Germano et al, 1991) away from the surface. We evaluate the performance of these surface models by simulating a neutraly stratified atmospheric boundary layer.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tournassat, C.; Tinnacher, R. M.; Grangeon, S.
The prediction of U(VI) adsorption onto montmorillonite clay is confounded by the complexities of: (1) the montmorillonite structure in terms of adsorption sites on basal and edge surfaces, and the complex interactions between the electrical double layers at these surfaces, and (2) U(VI) solution speciation, which can include cationic, anionic and neutral species. Previous U(VI)-montmorillonite adsorption and modeling studies have typically expanded classical surface complexation modeling approaches, initially developed for simple oxides, to include both cation exchange and surface complexation reactions. However, previous models have not taken into account the unique characteristics of electrostatic surface potentials that occur at montmorillonitemore » edge sites, where the electrostatic surface potential of basal plane cation exchange sites influences the surface potential of neighboring edge sites (‘spillover’ effect).« less
Tournassat, C.; Tinnacher, R. M.; Grangeon, S.; ...
2017-10-06
The prediction of U(VI) adsorption onto montmorillonite clay is confounded by the complexities of: (1) the montmorillonite structure in terms of adsorption sites on basal and edge surfaces, and the complex interactions between the electrical double layers at these surfaces, and (2) U(VI) solution speciation, which can include cationic, anionic and neutral species. Previous U(VI)-montmorillonite adsorption and modeling studies have typically expanded classical surface complexation modeling approaches, initially developed for simple oxides, to include both cation exchange and surface complexation reactions. However, previous models have not taken into account the unique characteristics of electrostatic surface potentials that occur at montmorillonitemore » edge sites, where the electrostatic surface potential of basal plane cation exchange sites influences the surface potential of neighboring edge sites (‘spillover’ effect).« less
NASA Astrophysics Data System (ADS)
Huang, Shih-Yu; Deng, Yi; Wang, Jingfeng
2017-09-01
The maximum-entropy-production (MEP) model of surface heat fluxes, based on contemporary non-equilibrium thermodynamics, information theory, and atmospheric turbulence theory, is used to re-estimate the global surface heat fluxes. The MEP model predicted surface fluxes automatically balance the surface energy budgets at all time and space scales without the explicit use of near-surface temperature and moisture gradient, wind speed and surface roughness data. The new MEP-based global annual mean fluxes over the land surface, using input data of surface radiation, temperature data from National Aeronautics and Space Administration-Clouds and the Earth's Radiant Energy System (NASA CERES) supplemented by surface specific humidity data from the Modern-Era Retrospective Analysis for Research and Applications (MERRA), agree closely with previous estimates. The new estimate of ocean evaporation, not using the MERRA reanalysis data as model inputs, is lower than previous estimates, while the new estimate of ocean sensible heat flux is higher than previously reported. The MEP model also produces the first global map of ocean surface heat flux that is not available from existing global reanalysis products.
Comparison of Response Surface and Kriging Models for Multidisciplinary Design Optimization
NASA Technical Reports Server (NTRS)
Simpson, Timothy W.; Korte, John J.; Mauery, Timothy M.; Mistree, Farrokh
1998-01-01
In this paper, we compare and contrast the use of second-order response surface models and kriging models for approximating non-random, deterministic computer analyses. After reviewing the response surface method for constructing polynomial approximations, kriging is presented as an alternative approximation method for the design and analysis of computer experiments. Both methods are applied to the multidisciplinary design of an aerospike nozzle which consists of a computational fluid dynamics model and a finite-element model. Error analysis of the response surface and kriging models is performed along with a graphical comparison of the approximations, and four optimization problems m formulated and solved using both sets of approximation models. The second-order response surface models and kriging models-using a constant underlying global model and a Gaussian correlation function-yield comparable results.
Digital terrain modeling and industrial surface metrology: Converging realms
Pike, R.J.
2001-01-01
Digital terrain modeling has a micro-and nanoscale counterpart in surface metrology, the numerical characterization of industrial surfaces. Instrumentation in semiconductor manufacturing and other high-technology fields can now contour surface irregularities down to the atomic scale. Surface metrology has been revolutionized by its ability to manipulate square-grid height matrices that are analogous to the digital elevation models (DEMs) used in physical geography. Because the shaping of industrial surfaces is a spatial process, the same concepts of analytical cartography that represent ground-surface form in geography evolved independently in metrology: The surface topography of manufactured components, exemplified here by automobile-engine cylinders, is routinely modeled by variogram analysis, relief shading, and most other techniques of parameterization and visualization familiar to geography. This article introduces industrial surface-metrology, examines the field in the context of terrain modeling and geomorphology and notes their similarities and differences, and raises theoretical issues to be addressed in progressing toward a unified practice of surface morphometry.
Some aerodynamic considerations related to wind tunnel model surface definition
NASA Technical Reports Server (NTRS)
Gloss, B. B.
1980-01-01
The aerodynamic considerations related to model surface definition are examined with particular emphasis in areas of fabrication tolerances, model surface finish, and orifice induced pressure errors. The effect of model surface roughness texture on skin friction is also discussed. It is shown that at a given Reynolds number, any roughness will produce no skin friction penalty.
Empirical Models for the Shielding and Reflection of Jet Mixing Noise by a Surface
NASA Technical Reports Server (NTRS)
Brown, Cliff
2015-01-01
Empirical models for the shielding and refection of jet mixing noise by a nearby surface are described and the resulting models evaluated. The flow variables are used to non-dimensionalize the surface position variables, reducing the variable space and producing models that are linear function of non-dimensional surface position and logarithmic in Strouhal frequency. A separate set of coefficients are determined at each observer angle in the dataset and linear interpolation is used to for the intermediate observer angles. The shielding and rejection models are then combined with existing empirical models for the jet mixing and jet-surface interaction noise sources to produce predicted spectra for a jet operating near a surface. These predictions are then evaluated against experimental data.
Empirical Models for the Shielding and Reflection of Jet Mixing Noise by a Surface
NASA Technical Reports Server (NTRS)
Brown, Clifford A.
2016-01-01
Empirical models for the shielding and reflection of jet mixing noise by a nearby surface are described and the resulting models evaluated. The flow variables are used to non-dimensionalize the surface position variables, reducing the variable space and producing models that are linear function of non-dimensional surface position and logarithmic in Strouhal frequency. A separate set of coefficients are determined at each observer angle in the dataset and linear interpolation is used to for the intermediate observer angles. The shielding and reflection models are then combined with existing empirical models for the jet mixing and jet-surface interaction noise sources to produce predicted spectra for a jet operating near a surface. These predictions are then evaluated against experimental data.
Dirmeyer, Paul A; Chen, Liang; Wu, Jiexia; Shin, Chul-Su; Huang, Bohua; Cash, Benjamin A; Bosilovich, Michael G; Mahanama, Sarith; Koster, Randal D; Santanello, Joseph A; Ek, Michael B; Balsamo, Gianpaolo; Dutra, Emanuel; Lawrence, D M
2018-02-01
We confront four model systems in three configurations (LSM, LSM+GCM, and reanalysis) with global flux tower observations to validate states, surface fluxes, and coupling indices between land and atmosphere. Models clearly under-represent the feedback of surface fluxes on boundary layer properties (the atmospheric leg of land-atmosphere coupling), and may over-represent the connection between soil moisture and surface fluxes (the terrestrial leg). Models generally under-represent spatial and temporal variability relative to observations, which is at least partially an artifact of the differences in spatial scale between model grid boxes and flux tower footprints. All models bias high in near-surface humidity and downward shortwave radiation, struggle to represent precipitation accurately, and show serious problems in reproducing surface albedos. These errors create challenges for models to partition surface energy properly and errors are traceable through the surface energy and water cycles. The spatial distribution of the amplitude and phase of annual cycles (first harmonic) are generally well reproduced, but the biases in means tend to reflect in these amplitudes. Interannual variability is also a challenge for models to reproduce. Our analysis illuminates targets for coupled land-atmosphere model development, as well as the value of long-term globally-distributed observational monitoring.
NASA Astrophysics Data System (ADS)
Drobny, Jon; Curreli, Davide; Ruzic, David; Lasa, Ane; Green, David; Canik, John; Younkin, Tim; Blondel, Sophie; Wirth, Brian
2017-10-01
Surface roughness greatly impacts material erosion, and thus plays an important role in Plasma-Surface Interactions. Developing strategies for efficiently introducing rough surfaces into ion-solid interaction codes will be an important step towards whole-device modeling of plasma devices and future fusion reactors such as ITER. Fractal TRIDYN (F-TRIDYN) is an upgraded version of the Monte Carlo, BCA program TRIDYN developed for this purpose that includes an explicit fractal model of surface roughness and extended input and output options for file-based code coupling. Code coupling with both plasma and material codes has been achieved and allows for multi-scale, whole-device modeling of plasma experiments. These code coupling results will be presented. F-TRIDYN has been further upgraded with an alternative, statistical model of surface roughness. The statistical model is significantly faster than and compares favorably to the fractal model. Additionally, the statistical model compares well to alternative computational surface roughness models and experiments. Theoretical links between the fractal and statistical models are made, and further connections to experimental measurements of surface roughness are explored. This work was supported by the PSI-SciDAC Project funded by the U.S. Department of Energy through contract DOE-DE-SC0008658.
Simple model of surface roughness for binary collision sputtering simulations
NASA Astrophysics Data System (ADS)
Lindsey, Sloan J.; Hobler, Gerhard; Maciążek, Dawid; Postawa, Zbigniew
2017-02-01
It has been shown that surface roughness can strongly influence the sputtering yield - especially at glancing incidence angles where the inclusion of surface roughness leads to an increase in sputtering yields. In this work, we propose a simple one-parameter model (the "density gradient model") which imitates surface roughness effects. In the model, the target's atomic density is assumed to vary linearly between the actual material density and zero. The layer width is the sole model parameter. The model has been implemented in the binary collision simulator IMSIL and has been evaluated against various geometric surface models for 5 keV Ga ions impinging an amorphous Si target. To aid the construction of a realistic rough surface topography, we have performed MD simulations of sequential 5 keV Ga impacts on an initially crystalline Si target. We show that our new model effectively reproduces the sputtering yield, with only minor variations in the energy and angular distributions of sputtered particles. The success of the density gradient model is attributed to a reduction of the reflection coefficient - leading to increased sputtering yields, similar in effect to surface roughness.
Reverse engineering of aircraft wing data using a partial differential equation surface model
NASA Astrophysics Data System (ADS)
Huband, Jacalyn Mann
Reverse engineering is a multi-step process used in industry to determine a production representation of an existing physical object. This representation is in the form of mathematical equations that are compatible with computer-aided design and computer-aided manufacturing (CAD/CAM) equipment. The four basic steps to the reverse engineering process are data acquisition, data separation, surface or curve fitting, and CAD/CAM production. The surface fitting step determines the design representation of the object, and thus is critical to the success or failure of the reverse engineering process. Although surface fitting methods described in the literature are used to model a variety of surfaces, they are not suitable for reversing aircraft wings. In this dissertation, we develop and demonstrate a new strategy for reversing a mathematical representation of an aircraft wing. The basis of our strategy is to take an aircraft design model and determine if an inverse model can be derived. A candidate design model for this research is the partial differential equation (PDE) surface model, proposed by Bloor and Wilson and used in the Rapid Airplane Parameter Input Design (RAPID) tool at the NASA-LaRC Geolab. There are several basic mathematical problems involved in reversing the PDE surface model: (i) deriving a computational approximation of the surface function; (ii) determining a radial parametrization of the wing; (iii) choosing mathematical models or classes of functions for representation of the boundary functions; (iv) fitting the boundary data points by the chosen boundary functions; and (v) simultaneously solving for the axial parameterization and the derivative boundary functions. The study of the techniques to solve the above mathematical problems has culminated in a reverse PDE surface model and two reverse PDE surface algorithms. One reverse PDE surface algorithm recovers engineering design parameters for the RAPID tool from aircraft wing data and the other generates a PDE surface model with spline boundary functions from an arbitrary set of grid points. Our numerical tests show that the reverse PDE surface model and the reverse PDE surface algorithms can be used for the reverse engineering of aircraft wing data.
NASA Technical Reports Server (NTRS)
Gibson, S. G.
1983-01-01
A system of computer programs was developed to model general three dimensional surfaces. Surfaces are modeled as sets of parametric bicubic patches. There are also capabilities to transform coordinates, to compute mesh/surface intersection normals, and to format input data for a transonic potential flow analysis. A graphical display of surface models and intersection normals is available. There are additional capabilities to regulate point spacing on input curves and to compute surface/surface intersection curves. Input and output data formats are described; detailed suggestions are given for user input. Instructions for execution are given, and examples are shown.
A soil-canopy scheme for use in a numerical model of the atmosphere: 1D stand-alone model
NASA Astrophysics Data System (ADS)
Kowalczyk, E. A.; Garratt, J. R.; Krummel, P. B.
We provide a detailed description of a soil-canopy scheme for use in the CSIRO general circulation models (GCMs) (CSIRO-4 and CSIRO-9), in the form of a one-dimensional stand-alone model. In addition, the paper documents the model's ability to simulate realistic surface fluxes by comparison with mesoscale model simulations (involving more sophisticated soil and boundary-layer treatments) and observations, and the diurnal range in surface quantities, including extreme maximum surface temperatures. The sensitivity of the model to values of the surface resistance is also quantified. The model represents phase 1 of a longer-term plan to improve the atmospheric boundary layer (ABL) and surface schemes in the CSIRO GCMs.
NASA Astrophysics Data System (ADS)
Park, Jun; Hwang, Seung-On
2017-11-01
The impact of a spectral nudging technique for the dynamical downscaling of the summer surface air temperature in a high-resolution regional atmospheric model is assessed. The performance of this technique is measured by comparing 16 analysis-driven simulation sets of physical parameterization combinations of two shortwave radiation and four land surface model schemes of the model, which are known to be crucial for the simulation of the surface air temperature. It is found that the application of spectral nudging to the outermost domain has a greater impact on the regional climate than any combination of shortwave radiation and land surface model physics schemes. The optimal choice of two model physics parameterizations is helpful for obtaining more realistic spatiotemporal distributions of land surface variables such as the surface air temperature, precipitation, and surface fluxes. However, employing spectral nudging adds more value to the results; the improvement is greater than using sophisticated shortwave radiation and land surface model physical parameterizations. This result indicates that spectral nudging applied to the outermost domain provides a more accurate lateral boundary condition to the innermost domain when forced by analysis data by securing the consistency with large-scale forcing over a regional domain. This consequently indirectly helps two physical parameterizations to produce small-scale features closer to the observed values, leading to a better representation of the surface air temperature in a high-resolution downscaled climate.
High Resolution Land Surface Modeling with the next generation Land Data Assimilation Systems
NASA Astrophysics Data System (ADS)
Kumar, S. V.; Eylander, J.; Peters-Lidard, C.
2005-12-01
Knowledge of land surface processes is important to many real-world applications such as agricultural production, water resources management, and flood predication. The Air Force Weather Agency (AFWA) has provided the USDA and other customers global soil moisture and temperature data for the past 30 years using the agrometeorological data assimilation model (now called AGRMET), merging atmospheric data. Further, accurate initialization of land surface conditions has been shown to greatly influence and improve weather forecast model and seasonal-to-interannual climate predictions. The AFWA AGRMET model exploits real time precipitation observations and analyses, global forecast model and satellite data to generate global estimates of soil moisture, soil temperature and other land surface states at 48km spatial resolution. However, to truly address the land surface initialization and climate prediction problem, and to mitigate the errors introduced by the differences in spatial scales of models, representations of land surface conditions need to be developed at the same fine scales such as that of cloud resolving models. NASA's Goddard Space Flight Center has developed an offline land data assimilation system known as the Land Information System (LIS) capable of modeling land atmosphere interactions at spatial resolutions as fine as 1km. LIS provides a software architecture that integrates the use of the state of the art land surface models, data assimilation techniques, and high performance computing and data management tools. LIS also employs many high resolution surface parameters such as the NASA Earth Observing System (EOS)-era products. In this study we describe the development of a next generation high resolution land surface modeling and data assimilation system, combining the capabilities of LIS and AGRMET. We investigate the influence of high resolution land surface data and observations on the land surface conditions by comparing with the operational AGRMET outputs.
Heating requirements and nonadiabatic surface effects for a model in the NTF cryogenic wind tunnel
NASA Technical Reports Server (NTRS)
Macha, J. M.; Landrum, D. B.; Pare, L. A., III; Johnson, C. B.
1988-01-01
A theoretical study has been made of the severity of nonadiabatic surface conditions arising from internal heat sources within a model in a cryogenic wind tunnel. Local surface heating is recognized as having an effect on the development of the boundary layer, which can introduce changes in the flow about the model and affect the wind tunnel data. The geometry was based on the NTF Pathfinder I wind tunnel model. A finite element heat transfer computer code was developed and used to compute the steady state temperature distribution within the body of the model, from which the surface temperature distribution was extracted. Particular three dimensional characteristics of the model were represented with various axisymmetric approximations of the geometry. This analysis identified regions on the surface of the model susceptible to surface heating and the magnitude of the respective surface temperatures. It was found that severe surface heating may occur in particular instances, but could be alleviated with adequate insulating material. The heat flux through the surface of the model was integrated to determine the net heat required to maintain the instrumentation cavity at the prescribed temperature. The influence of the nonadiabatic condition on boundary layer properties and on the validity of the wind tunnel simulation was also investigated.
Katsogiannis, Konstantinos Alexandros G; Vladisavljević, Goran T; Georgiadou, Stella; Rahmani, Ramin
2016-10-26
The effect of pore induction on increasing electrospun fibrous network specific surface area was investigated in this study. Theoretical models based on the available surface area of the fibrous network and exclusion of the surface area lost due to fiber-to-fiber contacts were developed. The models for calculation of the excluded area are based on Hertzian, Derjaguin-Muller-Toporov (DMT), and Johnson-Kendall-Roberts (JKR) contact models. Overall, the theoretical models correlated the network specific surface area to the material properties including density, surface tension, Young's modulus, Poisson's ratio, as well as network physical properties, such as density and geometrical characteristics including fiber radius, fiber aspect ratio and network thickness. Pore induction proved to increase the network specific surface area up to 52%, compared to the maximum surface area that could be achieved by nonporous fiber network with the same physical properties and geometrical characteristics. The model based on Johnson-Kendall-Roberts contact model describes accurately the fiber-to-fiber contact area under the experimental conditions used for pore generation. The experimental results and the theoretical model based on Johnson-Kendall-Roberts contact model show that the increase in network surface area due to pore induction can reach to up to 58%.
Magnetic Flux Transport at the Solar Surface
NASA Astrophysics Data System (ADS)
Jiang, J.; Hathaway, D. H.; Cameron, R. H.; Solanki, S. K.; Gizon, L.; Upton, L.
2014-12-01
After emerging to the solar surface, the Sun's magnetic field displays a complex and intricate evolution. The evolution of the surface field is important for several reasons. One is that the surface field, and its dynamics, sets the boundary condition for the coronal and heliospheric magnetic fields. Another is that the surface evolution gives us insight into the dynamo process. In particular, it plays an essential role in the Babcock-Leighton model of the solar dynamo. Describing this evolution is the aim of the surface flux transport model. The model starts from the emergence of magnetic bipoles. Thereafter, the model is based on the induction equation and the fact that after emergence the magnetic field is observed to evolve as if it were purely radial. The induction equation then describes how the surface flows—differential rotation, meridional circulation, granular, supergranular flows, and active region inflows—determine the evolution of the field (now taken to be purely radial). In this paper, we review the modeling of the various processes that determine the evolution of the surface field. We restrict our attention to their role in the surface flux transport model. We also discuss the success of the model and some of the results that have been obtained using this model.
Predictive model for ice formation on superhydrophobic surfaces.
Bahadur, Vaibhav; Mishchenko, Lidiya; Hatton, Benjamin; Taylor, J Ashley; Aizenberg, Joanna; Krupenkin, Tom
2011-12-06
The prevention and control of ice accumulation has important applications in aviation, building construction, and energy conversion devices. One area of active research concerns the use of superhydrophobic surfaces for preventing ice formation. The present work develops a physics-based modeling framework to predict ice formation on cooled superhydrophobic surfaces resulting from the impact of supercooled water droplets. This modeling approach analyzes the multiple phenomena influencing ice formation on superhydrophobic surfaces through the development of submodels describing droplet impact dynamics, heat transfer, and heterogeneous ice nucleation. These models are then integrated together to achieve a comprehensive understanding of ice formation upon impact of liquid droplets at freezing conditions. The accuracy of this model is validated by its successful prediction of the experimental findings that demonstrate that superhydrophobic surfaces can fully prevent the freezing of impacting water droplets down to surface temperatures of as low as -20 to -25 °C. The model can be used to study the influence of surface morphology, surface chemistry, and fluid and thermal properties on dynamic ice formation and identify parameters critical to achieving icephobic surfaces. The framework of the present work is the first detailed modeling tool developed for the design and analysis of surfaces for various ice prevention/reduction strategies. © 2011 American Chemical Society
The Creation of Space Vector Models of Buildings From RPAS Photogrammetry Data
NASA Astrophysics Data System (ADS)
Trhan, Ondrej
2017-06-01
The results of Remote Piloted Aircraft System (RPAS) photogrammetry are digital surface models and orthophotos. The main problem of the digital surface models obtained is that buildings are not perpendicular and the shape of roofs is deformed. The task of this paper is to obtain a more accurate digital surface model using building reconstructions. The paper discusses the problem of obtaining and approximating building footprints, reconstructing the final spatial vector digital building model, and modifying the buildings on the digital surface model.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mao, Jiafu; Phipps, S.J.; Pitman, A.J.
The CSIRO Mk3L climate system model, a reduced-resolution coupled general circulation model, has previously been described in this journal. The model is configured for millennium scale or multiple century scale simulations. This paper reports the impact of replacing the relatively simple land surface scheme that is the default parameterisation in Mk3L with a sophisticated land surface model that simulates the terrestrial energy, water and carbon balance in a physically and biologically consistent way. An evaluation of the new model s near-surface climatology highlights strengths and weaknesses, but overall the atmospheric variables, including the near-surface air temperature and precipitation, are simulatedmore » well. The impact of the more sophisticated land surface model on existing variables is relatively small, but generally positive. More significantly, the new land surface scheme allows an examination of surface carbon-related quantities including net primary productivity which adds significantly to the capacity of Mk3L. Overall, results demonstrate that this reduced-resolution climate model is a good foundation for exploring long time scale phenomena. The addition of the more sophisticated land surface model enables an exploration of important Earth System questions including land cover change and abrupt changes in terrestrial carbon storage.« less
Influence of World and Gravity Model Selection on Surface Interacting Vehicle Simulations
NASA Technical Reports Server (NTRS)
Madden, Michael M.
2007-01-01
A vehicle simulation is surface-interacting if the state of the vehicle (position, velocity, and acceleration) relative to the surface is important. Surface-interacting simulations perform ascent, entry, descent, landing, surface travel, or atmospheric flight. Modeling of gravity is an influential environmental factor for surface-interacting simulations. Gravity is the free-fall acceleration observed from a world-fixed frame that rotates with the world. Thus, gravity is the sum of gravitation and the centrifugal acceleration due to the world s rotation. In surface-interacting simulations, the fidelity of gravity at heights above the surface is more significant than gravity fidelity at locations in inertial space. A surface-interacting simulation cannot treat the gravity model separately from the world model, which simulates the motion and shape of the world. The world model's simulation of the world's rotation, or lack thereof, produces the centrifugal acceleration component of gravity. The world model s reproduction of the world's shape will produce different positions relative to the world center for a given height above the surface. These differences produce variations in the gravitation component of gravity. This paper examines the actual performance of world and gravity/gravitation pairs in a simulation using the Earth.
NASA Technical Reports Server (NTRS)
Simpson, Timothy W.
1998-01-01
The use of response surface models and kriging models are compared for approximating non-random, deterministic computer analyses. After discussing the traditional response surface approach for constructing polynomial models for approximation, kriging is presented as an alternative statistical-based approximation method for the design and analysis of computer experiments. Both approximation methods are applied to the multidisciplinary design and analysis of an aerospike nozzle which consists of a computational fluid dynamics model and a finite element analysis model. Error analysis of the response surface and kriging models is performed along with a graphical comparison of the approximations. Four optimization problems are formulated and solved using both approximation models. While neither approximation technique consistently outperforms the other in this example, the kriging models using only a constant for the underlying global model and a Gaussian correlation function perform as well as the second order polynomial response surface models.
Li, Ming Ze; Gao, Yuan Ke; Di, Xue Ying; Fan, Wen Yi
2016-03-01
The moisture content of forest surface soil is an important parameter in forest ecosystems. It is practically significant for forest ecosystem related research to use microwave remote sensing technology for rapid and accurate estimation of the moisture content of forest surface soil. With the aid of TDR-300 soil moisture content measuring instrument, the moisture contents of forest surface soils of 120 sample plots at Tahe Forestry Bureau of Daxing'anling region in Heilongjiang Province were measured. Taking the moisture content of forest surface soil as the dependent variable and the polarization decomposition parameters of C band Quad-pol SAR data as independent variables, two types of quantitative estimation models (multilinear regression model and BP-neural network model) for predicting moisture content of forest surface soils were developed. The spatial distribution of moisture content of forest surface soil on the regional scale was then derived with model inversion. Results showed that the model precision was 86.0% and 89.4% with RMSE of 3.0% and 2.7% for the multilinear regression model and the BP-neural network model, respectively. It indicated that the BP-neural network model had a better performance than the multilinear regression model in quantitative estimation of the moisture content of forest surface soil. The spatial distribution of forest surface soil moisture content in the study area was then obtained by using the BP neural network model simulation with the Quad-pol SAR data.
Wetting of crystalline polymer surfaces: A molecular dynamics simulation
NASA Astrophysics Data System (ADS)
Fan, Cun Feng; Caǧin, Tahir
1995-11-01
Molecular dynamics has been used to study the wetting of model polymer surfaces, the crystal surfaces of polyethylene (PE), poly(tetrafluoroethylene) (PTFE), and poly(ethylene terephthalate) (PET) by water and methylene iodide. In the simulation a liquid droplet is placed on a model surface and constant temperature, rigid body molecular dynamics is carried out while the model surface is kept fixed. A generally defined microscopic contact angle between a liquid droplet and a solid surface is quantitatively calculated from the volume of the droplet and the interfacial area between the droplet and the surface. The simulation results agree with the trend in experimental data for both water and methylene iodide. The shape of the droplets on the surface is analyzed and no obvious anisotropy of the droplets is seen in the surface plane, even though the crystal surfaces are highly oriented. The surface free energies of the model polymer surfaces are estimated from their contact angles with the two different liquid droplets.
NASA Technical Reports Server (NTRS)
Gibson, A. F.
1983-01-01
A system of computer programs has been developed to model general three-dimensional surfaces. Surfaces are modeled as sets of parametric bicubic patches. There are also capabilities to transform coordinate to compute mesh/surface intersection normals, and to format input data for a transonic potential flow analysis. A graphical display of surface models and intersection normals is available. There are additional capabilities to regulate point spacing on input curves and to compute surface intersection curves. Internal details of the implementation of this system are explained, and maintenance procedures are specified.
Assimilation of Surface Temperature in Land Surface Models
NASA Technical Reports Server (NTRS)
Lakshmi, Venkataraman
1998-01-01
Hydrological models have been calibrated and validated using catchment streamflows. However, using a point measurement does not guarantee correct spatial distribution of model computed heat fluxes, soil moisture and surface temperatures. With the advent of satellites in the late 70s, surface temperature is being measured two to four times a day from various satellite sensors and different platforms. The purpose of this paper is to demonstrate use of satellite surface temperature in (a) validation of model computed surface temperatures and (b) assimilation of satellite surface temperatures into a hydrological model in order to improve the prediction accuracy of soil moistures and heat fluxes. The assimilation is carried out by comparing the satellite and the model produced surface temperatures and setting the "true"temperature midway between the two values. Based on this "true" surface temperature, the physical relationships of water and energy balance are used to reset the other variables. This is a case of nudging the water and energy balance variables so that they are consistent with each other and the true" surface temperature. The potential of this assimilation scheme is demonstrated in the form of various experiments that highlight the various aspects. This study is carried over the Red-Arkansas basin in the southern United States (a 5 deg X 10 deg area) over a time period of a year (August 1987 - July 1988). The land surface hydrological model is run on an hourly time step. The results show that satellite surface temperature assimilation improves the accuracy of the computed surface soil moisture remarkably.
Butler, Samuel D; Nauyoks, Stephen E; Marciniak, Michael A
2015-11-02
A popular class of BRDF models is the microfacet models, where geometric optics is assumed. In contrast, more complex physical optics models may more accurately predict the BRDF, but the calculation is more resource intensive. These seemingly disparate approaches are compared in detail for the rough and smooth surface approximations of the modified Beckmann-Kirchhoff BRDF model, assuming Gaussian surface statistics. An approximation relating standard Fresnel reflection with the semi-rough surface polarization term, Q, is presented for unpolarized light. For rough surfaces, the angular dependence of direction cosine space is shown to be identical to the angular dependence in the microfacet distribution function. For polished surfaces, the same comparison shows a breakdown in the microfacet models. Similarities and differences between microfacet BRDF models and the modified Beckmann-Kirchhoff model are identified. The rationale for the original Beckmann-Kirchhoff F(bk)(2) geometric term relative to both microfacet models and generalized Harvey-Shack model is presented. A modification to the geometric F(bk)(2) term in original Beckmann-Kirchhoff BRDF theory is proposed.
Retrieval of Soil Moisture and Roughness from the Polarimetric Radar Response
NASA Technical Reports Server (NTRS)
Sarabandi, Kamal; Ulaby, Fawwaz T.
1997-01-01
The main objective of this investigation was the characterization of soil moisture using imaging radars. In order to accomplish this task, a number of intermediate steps had to be undertaken. In this proposal, the theoretical, numerical, and experimental aspects of electromagnetic scattering from natural surfaces was considered with emphasis on remote sensing of soil moisture. In the general case, the microwave backscatter from natural surfaces is mainly influenced by three major factors: (1) the roughness statistics of the soil surface, (2) soil moisture content, and (3) soil surface cover. First the scattering problem from bare-soil surfaces was considered and a hybrid model that relates the radar backscattering coefficient to soil moisture and surface roughness was developed. This model is based on extensive experimental measurements of the radar polarimetric backscatter response of bare soil surfaces at microwave frequencies over a wide range of moisture conditions and roughness scales in conjunction with existing theoretical surface scattering models in limiting cases (small perturbation, physical optics, and geometrical optics models). Also a simple inversion algorithm capable of providing accurate estimates of soil moisture content and surface rms height from single-frequency multi-polarization radar observations was developed. The accuracy of the model and its inversion algorithm is demonstrated using independent data sets. Next the hybrid model for bare-soil surfaces is made fully polarimetric by incorporating the parameters of the co- and cross-polarized phase difference into the model. Experimental data in conjunction with numerical simulations are used to relate the soil moisture content and surface roughness to the phase difference statistics. For this purpose, a novel numerical scattering simulation for inhomogeneous dielectric random surfaces was developed. Finally the scattering problem of short vegetation cover above a rough soil surface was considered. A general scattering model for grass-blades of arbitrary cross section was developed and incorporated in a first order random media model. The vegetation model and the bare-soil model are combined and the accuracy of the combined model is evaluated against experimental observations from a wheat field over the entire growing season. A complete set of ground-truth data and polarimetric backscatter data were collected. Also an inversion algorithm for estimating soil moisture and surface roughness from multi-polarized multi-frequency observations of vegetation-covered ground is developed.
DEVELOPMENT OF A LAND-SURFACE MODEL PART I: APPLICATION IN A MESOSCALE METEOROLOGY MODEL
Parameterization of land-surface processes and consideration of surface inhomogeneities are very important to mesoscale meteorological modeling applications, especially those that provide information for air quality modeling. To provide crucial, reliable information on the diurn...
Analytical fitting model for rough-surface BRDF.
Renhorn, Ingmar G E; Boreman, Glenn D
2008-08-18
A physics-based model is developed for rough surface BRDF, taking into account angles of incidence and scattering, effective index, surface autocovariance, and correlation length. Shadowing is introduced on surface correlation length and reflectance. Separate terms are included for surface scatter, bulk scatter and retroreflection. Using the FindFit function in Mathematica, the functional form is fitted to BRDF measurements over a wide range of incident angles. The model has fourteen fitting parameters; once these are fixed, the model accurately describes scattering data over two orders of magnitude in BRDF without further adjustment. The resulting analytical model is convenient for numerical computations.
Deformation and relaxation of an incompressible viscoelastic body with surface viscoelasticity
NASA Astrophysics Data System (ADS)
Liu, Liping; Yu, Miao; Lin, Hao; Foty, Ramsey
2017-01-01
Measuring mechanical properties of cells or cell aggregates has proven to be an involved process due to their geometrical and structural complexity. Past measurements are based on material models that completely neglect the elasticity of either the surface membrane or the interior bulk. In this work, we consider general material models to account for both surface and bulk viscoelasticity. The boundary value problems are formulated for deformations and relaxations of a closed viscoelastic surface coupled with viscoelastic media inside and outside of the surface. The linearized surface elasticity models are derived for the constant surface tension model and the Helfrich-Canham bending model for coupling with the bulk viscoelasticity. For quasi-spherical surfaces, explicit solutions are obtained for the deformation, stress-strain and relaxation behaviors under a variety of loading conditions. These solutions can be applied to extract the intrinsic surface and bulk viscoelastic properties of biological cells or cell aggregates in the indentation, electro-deformation and relaxation experiments.
NASA Astrophysics Data System (ADS)
Bokarev, Valery P.; Krasnikov, Gennady Ya
2018-02-01
Based on the evaluation of the properties of crystals, such as surface energy and its anisotropy, the surface melting temperature, the anisotropy of the work function of the electron, and the anisotropy of adsorption, were shown the advantages of the model of coordination melting (MCM) in calculating the surface properties of crystals. The model of coordination melting makes it possible to calculate with an acceptable accuracy the specific surface energy of the crystals, the anisotropy of the surface energy, the habit of the natural crystals, the temperature of surface melting of the crystal, the anisotropy of the electron work function and the anisotropy of the adhesive properties of single-crystal surfaces. The advantage of our model is the simplicity of evaluating the surface properties of the crystal based on the data given in the reference literature. In this case, there is no need for a complex mathematical tool, which is used in calculations using quantum chemistry or modeling by molecular dynamics.
NASA Astrophysics Data System (ADS)
Karakoti, Indira; Kesarwani, Kapil; Mehta, Manish; Dobhal, D. P.
2016-10-01
Two enhanced temperature-index (T-index) models are proposed by incorporating meteorological parameters viz. relative humidity, wind speed and net radiation. The models are an attempt to explore different climatic variables other than temperature affecting glacier surface melting. Weather data were recorded at Chorabari Glacier using an automatic weather station during the summers of 2010 (July 10 to September 10) and 2012 (June 10 to October 25). The modelled surface melt is validated against the measured point surface melting at the snout. Performance of the developed models is evaluated by comparing with basic temperature-index model and is quantified through different efficiency criteria. The results suggest that proposed models yield considerable improvement in surface melt simulation . Consequently, the study reveals that glacier surface melt depends not only on temperature but also on weather parameters viz. relative humidity, wind speed and net radiation play a significant role in glacier surface melting. This approach provides a major improvement on basic temperature-index method and offers an alternative to energy balance model.
Chu, Khim Hoong
2017-11-09
Surface diffusion coefficients may be estimated by fitting solutions of a diffusion model to batch kinetic data. For non-linear systems, a numerical solution of the diffusion model's governing equations is generally required. We report here the application of the classic Langmuir kinetics model to extract surface diffusion coefficients from batch kinetic data. The use of the Langmuir kinetics model in lieu of the conventional surface diffusion model allows derivation of an analytical expression. The parameter estimation procedure requires determining the Langmuir rate coefficient from which the pertinent surface diffusion coefficient is calculated. Surface diffusion coefficients within the 10 -9 to 10 -6 cm 2 /s range obtained by fitting the Langmuir kinetics model to experimental kinetic data taken from the literature are found to be consistent with the corresponding values obtained from the traditional surface diffusion model. The virtue of this simplified parameter estimation method is that it reduces the computational complexity as the analytical expression involves only an algebraic equation in closed form which is easily evaluated by spreadsheet computation.
Modeling Surface Growth of Escherichia coli on Agar Plates
Fujikawa, Hiroshi; Morozumi, Satoshi
2005-01-01
Surface growth of Escherichia coli cells on a membrane filter placed on a nutrient agar plate under various conditions was studied with a mathematical model. The surface growth of bacterial cells showed a sigmoidal curve with time on a semilogarithmic plot. To describe it, a new logistic model that we presented earlier (H. Fujikawa et al., Food Microbiol. 21:501-509, 2004) was modified. Growth curves at various constant temperatures (10 to 34°C) were successfully described with the modified model (model III). Model III gave better predictions of the rate constant of growth and the lag period than a modified Gompertz model and the Baranyi model. Using the parameter values of model III at the constant temperatures, surface growth at various temperatures was successfully predicted. Surface growth curves at various initial cell numbers were also sigmoidal and converged to the same maximum cell numbers at the stationary phase. Surface growth curves at various nutrient levels were also sigmoidal. The maximum cell number and the rate of growth were lower as the nutrient level decreased. The surface growth curve was the same as that in a liquid, except for the large curvature at the deceleration period. These curves were also well described with model III. The pattern of increase in the ATP content of cells grown on a surface was sigmoidal, similar to that for cell growth. We discovered several characteristics of the surface growth of bacterial cells under various growth conditions and examined the applicability of our model to describe these growth curves. PMID:16332768
Matching Images to Models: Camera Calibration for 3-D Surface Reconstruction
NASA Technical Reports Server (NTRS)
Morris, Robin D.; Smelyanskiy, Vadim N.; Cheeseman. Peter C.; Norvig, Peter (Technical Monitor)
2001-01-01
In a previous paper we described a system which recursively recovers a super-resolved three dimensional surface model from a set of images of the surface. In that paper we assumed that the camera calibration for each image was known. In this paper we solve two problems. Firstly, if an estimate of the surface is already known, the problem is to calibrate a new image relative to the existing surface model. Secondly, if no surface estimate is available, the relative camera calibration between the images in the set must be estimated. This will allow an initial surface model to be estimated. Results of both types of estimation are given.
NASA Astrophysics Data System (ADS)
Bergslien, Elisa; Fountain, John; Giese, Rossman
2004-05-01
Epoxy models have been used as analogs for fractured rock surfaces in many laboratory investigations of multiphase flow processes. However, there is no agreement on how well or poorly such an analog replicates the surface chemistry of geologic materials, nor is there a satisfactory analysis of the surface properties of epoxy. This paper addresses the issue of accurately characterizing the surface chemistry of a typical epoxy used in laboratory multiphase flow studies and comparing that surface to a polystyrene surface and a radio frequency glow discharge treated polystyrene surface. Surface properties were determined using direct contact angle measurements of polar and apolar liquids on flat test samples. The epoxy was determined to have surface properties as follows: γ = 62.3, γLW = 39, γAB = 23.3, γ⊕ = 0, and γ? = 23.3 mJ/m2, where γ is the total surface tension of the solid, γLW is the Lifshitz-van der Waals (LW) surface tension component, γAB is the Lewis acid base (AB) surface tension component, γ? is the electron-donor (negative) parameter, and γ⊕ is the electron-acceptor (positive) parameter. Values of γ? < 27.9 mJ/m2 indicate a hydrophobic surface, which means that epoxy is not a good analog for most geologic materials. This study also explores the use of radio frequency glow discharge plasma to add hydroxyl functionality to polymer surfaces producing a material with alterable surface properties and the same optical and casting properties as epoxy. Using this method, the degree of alteration of the surface chemistry of polymer fracture models can be controlled, allowing the creation of models with a variety of different wettabilities. The resultant models were found to be durable, long lasting, and a potentially very useful alternative to the more typical epoxy models.
A surface temperature and moisture parameterization for use in mesoscale numerical models
NASA Technical Reports Server (NTRS)
Tremback, C. J.; Kessler, R.
1985-01-01
A modified multi-level soil moisture and surface temperature model is presented for use as in defining lower boundary conditions in mesoscale weather models. Account is taken of the hydraulic and thermal diffusion properties of the soil, their variations with soil type, and the mixing ratio at the surface. Techniques are defined for integrating the surface input into the multi-level scheme. Sample simulation runs were performed with the modified model and the original model defined by Pielke, et al. (1977, 1981). The models were applied to regional weather forecasting over soils composed of sand and clay loam. The new form of the model avoided iterations necessary in the earlier version of the model and achieved convergence at reasonable profiles for surface temperature and moisture in regions where the earlier version of the model failed.
Gao, X-L; Zhang, G Y
2016-07-01
A non-classical model for a Mindlin plate resting on an elastic foundation is developed in a general form using a modified couple stress theory, a surface elasticity theory and a two-parameter Winkler-Pasternak foundation model. It includes all five kinematic variables possible for a Mindlin plate. The equations of motion and the complete boundary conditions are obtained simultaneously through a variational formulation based on Hamilton's principle, and the microstructure, surface energy and foundation effects are treated in a unified manner. The newly developed model contains one material length-scale parameter to describe the microstructure effect, three surface elastic constants to account for the surface energy effect, and two foundation parameters to capture the foundation effect. The current non-classical plate model reduces to its classical elasticity-based counterpart when the microstructure, surface energy and foundation effects are all suppressed. In addition, the new model includes the Mindlin plate models considering the microstructure dependence or the surface energy effect or the foundation influence alone as special cases, recovers the Kirchhoff plate model incorporating the microstructure, surface energy and foundation effects, and degenerates to the Timoshenko beam model including the microstructure effect. To illustrate the new Mindlin plate model, the static bending and free vibration problems of a simply supported rectangular plate are analytically solved by directly applying the general formulae derived.
Zhang, G. Y.
2016-01-01
A non-classical model for a Mindlin plate resting on an elastic foundation is developed in a general form using a modified couple stress theory, a surface elasticity theory and a two-parameter Winkler–Pasternak foundation model. It includes all five kinematic variables possible for a Mindlin plate. The equations of motion and the complete boundary conditions are obtained simultaneously through a variational formulation based on Hamilton's principle, and the microstructure, surface energy and foundation effects are treated in a unified manner. The newly developed model contains one material length-scale parameter to describe the microstructure effect, three surface elastic constants to account for the surface energy effect, and two foundation parameters to capture the foundation effect. The current non-classical plate model reduces to its classical elasticity-based counterpart when the microstructure, surface energy and foundation effects are all suppressed. In addition, the new model includes the Mindlin plate models considering the microstructure dependence or the surface energy effect or the foundation influence alone as special cases, recovers the Kirchhoff plate model incorporating the microstructure, surface energy and foundation effects, and degenerates to the Timoshenko beam model including the microstructure effect. To illustrate the new Mindlin plate model, the static bending and free vibration problems of a simply supported rectangular plate are analytically solved by directly applying the general formulae derived. PMID:27493578
NASA Astrophysics Data System (ADS)
Villard, Jean-Francois; Schyns, Marc
2010-12-01
Optimizing the life cycle of nuclear systems under safety constraints requires high-performance experimental programs to reduce uncertainties on margins and limits. In addition to improvement in modeling and simulation, innovation in instrumentation is crucial for analytical and integral experiments conducted in research reactors. The quality of nuclear research programs relies obviously on an excellent knowledge of their experimental environment which constantly calls for better online determination of neutron and gamma flux. But the combination of continuously increasing scientific requirements and new experimental domains -brought for example by Generation IV programsnecessitates also major innovations for in-pile measurements of temperature, dimensions, pressure or chemical analysis in innovative mediums. At the same time, the recent arising of a European platform around the building of the Jules Horowitz Reactor offers new opportunities for research institutes and organizations to pool their resources in order to face these technical challenges. In this situation, CEA (French Nuclear Energy Commission) and SCK'CEN (Belgian Nuclear Research Centre) have combined their efforts and now share common developments through a Joint Instrumentation Laboratory. Significant progresses have thus been obtained recently in the field of in-pile measurements, on one hand by improvement of existing measurement methods, and on the other hand by introduction in research reactors of original measurement techniques. This paper highlights the state-of-the-art and the main requirements regarding in-pile measurements, particularly for the needs of current and future irradiation programs performed in material testing reactors. Some of the main on-going developments performed in the framework of the Joint Instrumentation Laboratory are also described, such as: - a unique fast neutron flux measurement system using fission chambers with 242Pu deposit and a specific online data processing, - an optical system designed to perform in-pile dimensional measurements of material samples under irradiation, - an acoustical instrumentation allowing the online characterization of fission gas release in Pressurized Water Reactor fuel rods. For each example, the obtained results, expected impacts and development status are detailed.
NASA Astrophysics Data System (ADS)
Unnikrishnan, C. K.; Rajeevan, M.; Rao, S. Vijaya Bhaskara
2016-06-01
The direct impact of high resolution land surface initialization on the forecast bias in a regional climate model in recent years over Indian summer monsoon region is investigated. Two sets of regional climate model simulations are performed, one with a coarse resolution land surface initial conditions and second one used a high resolution land surface data for initial condition. The results show that all monsoon years respond differently to the high resolution land surface initialization. The drought monsoon year 2009 and extended break periods were more sensitive to the high resolution land surface initialization. These results suggest that the drought monsoon year predictions can be improved with high resolution land surface initialization. Result also shows that there are differences in the response to the land surface initialization within the monsoon season. Case studies of heat wave and a monsoon depression simulation show that, the model biases were also improved with high resolution land surface initialization. These results show the need for a better land surface initialization strategy in high resolution regional models for monsoon forecasting.
NASA Astrophysics Data System (ADS)
Peng, Xiang-Long; Husser, Edgar; Huang, Gan-Yun; Bargmann, Swantje
2018-03-01
A finite-deformation gradient crystal plasticity theory is developed, which takes into account the interaction between dislocations and surfaces. The model captures both energetic and dissipative effects for surfaces penetrable by dislocations. By taking advantage of the principle of virtual power, the surface microscopic boundary equations are obtained naturally. Surface equations govern surface yielding and hardening. A thin film under shear deformation serves as a benchmark problem for validation of the proposed model. It is found that both energetic and dissipative surface effects significantly affect the plastic behavior.
Real Time Land-Surface Hydrologic Modeling Over Continental US
NASA Technical Reports Server (NTRS)
Houser, Paul R.
1998-01-01
The land surface component of the hydrological cycle is fundamental to the overall functioning of the atmospheric and climate processes. Spatially and temporally variable rainfall and available energy, combined with land surface heterogeneity cause complex variations in all processes related to surface hydrology. The characterization of the spatial and temporal variability of water and energy cycles are critical to improve our understanding of land surface-atmosphere interaction and the impact of land surface processes on climate extremes. Because the accurate knowledge of these processes and their variability is important for climate predictions, most Numerical Weather Prediction (NWP) centers have incorporated land surface schemes in their models. However, errors in the NWP forcing accumulate in the surface and energy stores, leading to incorrect surface water and energy partitioning and related processes. This has motivated the NWP to impose ad hoc corrections to the land surface states to prevent this drift. A proposed methodology is to develop Land Data Assimilation schemes (LDAS), which are uncoupled models forced with observations, and not affected by NWP forcing biases. The proposed research is being implemented as a real time operation using an existing Surface Vegetation Atmosphere Transfer Scheme (SVATS) model at a 40 km degree resolution across the United States to evaluate these critical science questions. The model will be forced with real time output from numerical prediction models, satellite data, and radar precipitation measurements. Model parameters will be derived from the existing GIS vegetation and soil coverages. The model results will be aggregated to various scales to assess water and energy balances and these will be validated with various in-situ observations.
Land Surface Data Assimilation
NASA Astrophysics Data System (ADS)
Houser, P. R.
2012-12-01
Information about land surface water, energy and carbon conditions is of critical importance to real-world applications such as agricultural production, water resource management, flood prediction, water supply, weather and climate forecasting, and environmental preservation. While ground-based observational networks are improving, the only practical way to observe these land surface states on continental to global scales is via satellites. Remote sensing can make spatially comprehensive measurements of various components of the terrestrial system, but it cannot provide information on the entire system (e.g. evaporation), and the observations represent only an instant in time. Land surface process models may be used to predict temporal and spatial terrestrial dynamics, but these predictions are often poor, due to model initialization, parameter and forcing, and physics errors. Therefore, an attractive prospect is to combine the strengths of land surface models and observations (and minimize the weaknesses) to provide a superior terrestrial state estimate. This is the goal of land surface data assimilation. Data Assimilation combines observations into a dynamical model, using the model's equations to provide time continuity and coupling between the estimated fields. Land surface data assimilation aims to utilize both our land surface process knowledge, as embodied in a land surface model, and information that can be gained from observations. Both model predictions and observations are imperfect and we wish to use both synergistically to obtain a more accurate result. Moreover, both contain different kinds of information, that when used together, provide an accuracy level that cannot be obtained individually. Model biases can be mitigated using a complementary calibration and parameterization process. Limited point measurements are often used to calibrate the model(s) and validate the assimilation results. This presentation will provide a brief background on land surface observation, modeling and data assimilation, followed by a discussion of various hydrologic data assimilation challenges, and finally conclude with several land surface data assimilation case studies.
NASA Astrophysics Data System (ADS)
Meng, Qingyong; Meyer, Hans-Dieter
2015-10-01
Molecular-surface studies are often done by assuming a corrugated, static (i.e., rigid) surface. To be able to investigate the effects that vibrations of surface atoms may have on spectra and cross sections, an expansion Hamiltonian model is proposed on the basis of the recently reported [R. Marquardt et al., J. Chem. Phys. 132, 074108 (2010)] SAP potential energy surface (PES), which was built for the CO/Cu(100) system with a rigid surface. In contrast to other molecule-surface coupling models, such as the modified surface oscillator model, the coupling between the adsorbed molecule and the surface atoms is already included in the present expansion SAP-PES model, in which a Taylor expansion around the equilibrium positions of the surface atoms is performed. To test the quality of the Taylor expansion, a direct model, that is avoiding the expansion, is also studied. The latter, however, requests that there is only one movable surface atom included. On the basis of the present expansion and direct models, the effects of a moving top copper atom (the one to which CO is bound) on the energy levels of a bound CO/Cu(100) system are studied. For this purpose, the multiconfiguration time-dependent Hartree calculations are carried out to obtain the vibrational fundamentals and overtones of the CO/Cu(100) system including a movable top copper atom. In order to interpret the results, a simple model consisting of two coupled harmonic oscillators is introduced. From these calculations, the vibrational levels of the CO/Cu(100) system as function of the frequency of the top copper atom are discussed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meng, Qingyong, E-mail: mengqingyong@dicp.ac.cn; Meyer, Hans-Dieter, E-mail: hans-dieter.meyer@pci.uni-heidelberg.de
2015-10-28
Molecular-surface studies are often done by assuming a corrugated, static (i.e., rigid) surface. To be able to investigate the effects that vibrations of surface atoms may have on spectra and cross sections, an expansion Hamiltonian model is proposed on the basis of the recently reported [R. Marquardt et al., J. Chem. Phys. 132, 074108 (2010)] SAP potential energy surface (PES), which was built for the CO/Cu(100) system with a rigid surface. In contrast to other molecule-surface coupling models, such as the modified surface oscillator model, the coupling between the adsorbed molecule and the surface atoms is already included in themore » present expansion SAP-PES model, in which a Taylor expansion around the equilibrium positions of the surface atoms is performed. To test the quality of the Taylor expansion, a direct model, that is avoiding the expansion, is also studied. The latter, however, requests that there is only one movable surface atom included. On the basis of the present expansion and direct models, the effects of a moving top copper atom (the one to which CO is bound) on the energy levels of a bound CO/Cu(100) system are studied. For this purpose, the multiconfiguration time-dependent Hartree calculations are carried out to obtain the vibrational fundamentals and overtones of the CO/Cu(100) system including a movable top copper atom. In order to interpret the results, a simple model consisting of two coupled harmonic oscillators is introduced. From these calculations, the vibrational levels of the CO/Cu(100) system as function of the frequency of the top copper atom are discussed.« less
NASA Astrophysics Data System (ADS)
Glaser, Barbara; Klaus, Julian; Frei, Sven; Frentress, Jay; Pfister, Laurent; Hopp, Luisa
2016-10-01
The highly dynamic processes within a hillslope-riparian-stream (HRS) continuum are known to affect streamflow generation, but are yet not fully understood. Within this study, we simulated a headwater HRS continuum in western Luxembourg with an integrated hydrologic surface subsurface model (HydroGeoSphere). The model was setup with thorough consideration of catchment-specific attributes and we performed a multicriteria model evaluation (4 years) with special focus on the temporally varying spatial patterns of surface saturation. We used a portable thermal infrared (TIR) camera to map surface saturation with a high spatial resolution and collected 20 panoramic snapshots of the riparian zone (approx. 10 m × 20 m) under different hydrologic conditions. Qualitative and quantitative comparison of the processed TIR panoramas and the corresponding model output panoramas revealed a good agreement between spatiotemporal dynamic model and field surface saturation patterns. A double logarithmic linear relationship between surface saturation extent and discharge was similar for modeled and observed data. This provided confidence in the capability of an integrated hydrologic surface subsurface model to represent temporal and spatial water flux dynamics at small (HRS continuum) scales. However, model scenarios with different parameterizations of the riparian zone showed that discharge and surface saturation were controlled by different parameters and hardly influenced each other. Surface saturation only affected very fast runoff responses with a small volumetric contribution to stream discharge, indicating that the dynamic surface saturation in the riparian zone does not necessarily imply a major control on runoff generation.
Coupled land surface/hydrologic/atmospheric models
NASA Technical Reports Server (NTRS)
Pielke, Roger; Steyaert, Lou; Arritt, Ray; Lahtakia, Mercedes; Smith, Chris; Ziegler, Conrad; Soong, Su Tzai; Avissar, Roni; Wetzel, Peter; Sellers, Piers
1993-01-01
The topics covered include the following: prototype land cover characteristics data base for the conterminous United States; surface evapotranspiration effects on cumulus convection and implications for mesoscale models; the use of complex treatment of surface hydrology and thermodynamics within a mesoscale model and some related issues; initialization of soil-water content for regional-scale atmospheric prediction models; impact of surface properties on dryline and MCS evolution; a numerical simulation of heavy precipitation over the complex topography of California; representing mesoscale fluxes induced by landscape discontinuities in global climate models; emphasizing the role of subgrid-scale heterogeneity in surface-air interaction; and problems with modeling and measuring biosphere-atmosphere exchanges of energy, water, and carbon on large scales.
NASA Astrophysics Data System (ADS)
Park, C.; Lee, J.; Koo, M.
2011-12-01
Climate is the most critical driving force of the hydrologic system of the Earth. Since the industrial revolution, the impacts of anthropogenic activities to the Earth environment have been expanded and accelerated. Especially, the global emission of carbon dioxide into the atmosphere is known to have significantly increased temperature and affected the hydrologic system. Many hydrologists have contributed to the studies regarding the climate change on the hydrologic system since the Intergovernmental Panel on Climate Change (IPCC) was created in 1988. Among many components in the hydrologic system groundwater and its response to the climate change and anthropogenic activities are not fully understood due to the complexity of subsurface conditions between the surface and the groundwater table. A new spatio-temporal hydrologic model has been developed to estimate the impacts of climate change and land use dynamics on the groundwater. The model consists of two sub-models: a surface model and a subsurface model. The surface model involves three surface processes: interception, runoff, and evapotranspiration, and the subsurface model does also three subsurface processes: soil moisture balance, recharge, and groundwater flow. The surface model requires various input data including land use, soil types, vegetation types, topographical elevations, and meteorological data. The surface model simulates daily hydrological processes for rainfall interception, surface runoff varied by land use change and crop growth, and evapotranspiration controlled by soil moisture balance. The daily soil moisture balance is a key element to link two sub-models as it calculates infiltration and groundwater recharge by considering a time delay routing through a vadose zone down to the groundwater table. MODFLOW is adopted to simulate groundwater flow and interaction with surface water components as well. The model is technically flexible to add new model or modify existing model as it is developed with an object-oriented language - Python. The model also can easily be localized by simple modification of soil and crop properties. The actual application of the model after calibration was successful and results showed reliable water balance and interaction between the surface and subsurface hydrologic systems.
Software Surface Modeling and Grid Generation Steering Committee
NASA Technical Reports Server (NTRS)
Smith, Robert E. (Editor)
1992-01-01
It is a NASA objective to promote improvements in the capability and efficiency of computational fluid dynamics. Grid generation, the creation of a discrete representation of the solution domain, is an essential part of computational fluid dynamics. However, grid generation about complex boundaries requires sophisticated surface-model descriptions of the boundaries. The surface modeling and the associated computation of surface grids consume an extremely large percentage of the total time required for volume grid generation. Efficient and user friendly software systems for surface modeling and grid generation are critical for computational fluid dynamics to reach its potential. The papers presented here represent the state-of-the-art in software systems for surface modeling and grid generation. Several papers describe improved techniques for grid generation.
NASA Astrophysics Data System (ADS)
Anderson, William; Meneveau, Charles
2010-05-01
A dynamic subgrid-scale (SGS) parameterization for hydrodynamic surface roughness is developed for large-eddy simulation (LES) of atmospheric boundary layer (ABL) flow over multiscale, fractal-like surfaces. The model consists of two parts. First, a baseline model represents surface roughness at horizontal length-scales that can be resolved in the LES. This model takes the form of a force using a prescribed drag coefficient. This approach is tested in LES of flow over cubes, wavy surfaces, and ellipsoidal roughness elements for which there are detailed experimental data available. Secondly, a dynamic roughness model is built, accounting for SGS surface details of finer resolution than the LES grid width. The SGS boundary condition is based on the logarithmic law of the wall, where the unresolved roughness of the surface is modeled as the product of local root-mean-square (RMS) of the unresolved surface height and an unknown dimensionless model coefficient. This coefficient is evaluated dynamically by comparing the plane-average hydrodynamic drag at two resolutions (grid- and test-filter scale, Germano et al., 1991). The new model is tested on surfaces generated through superposition of random-phase Fourier modes with prescribed, power-law surface-height spectra. The results show that the method yields convergent results and correct trends. Limitations and further challenges are highlighted. Supported by the US National Science Foundation (EAR-0609690).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Macha, J.M.; Landrum, D.B.; Pare, L.A. III
1988-01-01
A theoretical study has been made of the severity of nonadiabatic surface conditions arising from internal heat sources within a model in a cryogenic wind tunnel. Local surface heating is recognized as having an effect on the development of the boundary layer, which can introduce changes in the flow about the model and affect the wind tunnel data. The geometry was based on the NTF Pathfinder I wind tunnel model. A finite element heat transfer computer code was developed and used to compute the steady state temperature distribution within the body of the model, from which the surface temperature distributionmore » was extracted. Particular three dimensional characteristics of the model were represented with various axisymmetric approximations of the geometry. This analysis identified regions on the surface of the model susceptible to surface heating and the magnitude of the respective surface temperatures. It was found that severe surface heating may occur in particular instances, but could be alleviated with adequate insulating material. The heat flux through the surface of the model was integrated to determine the net heat required to maintain the instrumentation cavity at the prescribed temperature. The influence of the nonadiabatic condition on boundary layer properties and on the validity of the wind tunnel simulation was also investigated. 20 refs., 12 figs.« less
NASA Technical Reports Server (NTRS)
Liang, XU; Lettenmaier, Dennis P.; Wood, Eric F.; Burges, Stephen J.
1994-01-01
A generalization of the single soil layer variable infiltration capacity (VIC) land surface hydrological model previously implemented in the Geophysical Fluid Dynamics Laboratory (GFDL) general circulation model (GCM) is described. The new model is comprised of a two-layer characterization of the soil column, and uses an aerodynamic representation of the latent and sensible heat fluxes at the land surface. The infiltration algorithm for the upper layer is essentially the same as for the single layer VIC model, while the lower layer drainage formulation is of the form previously implemented in the Max-Planck-Institut GCM. The model partitions the area of interest (e.g., grid cell) into multiple land surface cover types; for each land cover type the fraction of roots in the upper and lower zone is specified. Evapotranspiration consists of three components: canopy evaporation, evaporation from bare soils, and transpiration, which is represented using a canopy and architectural resistance formulation. Once the latent heat flux has been computed, the surface energy balance is iterated to solve for the land surface temperature at each time step. The model was tested using long-term hydrologic and climatological data for Kings Creek, Kansas to estimate and validate the hydrological parameters, and surface flux data from three First International Satellite Land Surface Climatology Project Field Experiment (FIFE) intensive field campaigns in the summer-fall of 1987 to validate the surface energy fluxes.
An equivalent body surface charge model representing three-dimensional bioelectrical activity
NASA Technical Reports Server (NTRS)
He, B.; Chernyak, Y. B.; Cohen, R. J.
1995-01-01
A new surface-source model has been developed to account for the bioelectrical potential on the body surface. A single-layer surface-charge model on the body surface has been developed to equivalently represent bioelectrical sources inside the body. The boundary conditions on the body surface are discussed in relation to the surface-charge in a half-space conductive medium. The equivalent body surface-charge is shown to be proportional to the normal component of the electric field on the body surface just outside the body. The spatial resolution of the equivalent surface-charge distribution appears intermediate between those of the body surface potential distribution and the body surface Laplacian distribution. An analytic relationship between the equivalent surface-charge and the surface Laplacian of the potential was found for a half-space conductive medium. The effects of finite spatial sampling and noise on the reconstruction of the equivalent surface-charge were evaluated by computer simulations. It was found through computer simulations that the reconstruction of the equivalent body surface-charge from the body surface Laplacian distribution is very stable against noise and finite spatial sampling. The present results suggest that the equivalent body surface-charge model may provide an additional insight to our understanding of bioelectric phenomena.
Modeling and validation of spectral BRDF on material surface of space target
NASA Astrophysics Data System (ADS)
Hou, Qingyu; Zhi, Xiyang; Zhang, Huili; Zhang, Wei
2014-11-01
The modeling and the validation methods of the spectral BRDF on the material surface of space target were presented. First, the microscopic characteristics of the space targets' material surface were analyzed based on fiber-optic spectrometer using to measure the direction reflectivity of the typical materials surface. To determine the material surface of space target is isotropic, atomic force microscopy was used to measure the material surface structure of space target and obtain Gaussian distribution model of microscopic surface element height. Then, the spectral BRDF model based on that the characteristics of the material surface were isotropic and the surface micro-facet with the Gaussian distribution which we obtained was constructed. The model characterizes smooth and rough surface well for describing the material surface of the space target appropriately. Finally, a spectral BRDF measurement platform in a laboratory was set up, which contains tungsten halogen lamp lighting system, fiber optic spectrometer detection system and measuring mechanical systems with controlling the entire experimental measurement and collecting measurement data by computers automatically. Yellow thermal control material and solar cell were measured with the spectral BRDF, which showed the relationship between the reflection angle and BRDF values at three wavelengths in 380nm, 550nm, 780nm, and the difference between theoretical model values and the measured data was evaluated by relative RMS error. Data analysis shows that the relative RMS error is less than 6%, which verified the correctness of the spectral BRDF model.
Empirical measurement and model validation of infrared spectra of contaminated surfaces
NASA Astrophysics Data System (ADS)
Archer, Sean; Gartley, Michael; Kerekes, John; Cosofret, Bogdon; Giblin, Jay
2015-05-01
Liquid-contaminated surfaces generally require more sophisticated radiometric modeling to numerically describe surface properties. The Digital Imaging and Remote Sensing Image Generation (DIRSIG) Model utilizes radiative transfer modeling to generate synthetic imagery. Within DIRSIG, a micro-scale surface property model (microDIRSIG) was used to calculate numerical bidirectional reflectance distribution functions (BRDF) of geometric surfaces with applied concentrations of liquid contamination. Simple cases where the liquid contamination was well described by optical constants on optically at surfaces were first analytically evaluated by ray tracing and modeled within microDIRSIG. More complex combinations of surface geometry and contaminant application were then incorporated into the micro-scale model. The computed microDIRSIG BRDF outputs were used to describe surface material properties in the encompassing DIRSIG simulation. These DIRSIG generated outputs were validated with empirical measurements obtained from a Design and Prototypes (D&P) Model 102 FTIR spectrometer. Infrared spectra from the synthetic imagery and the empirical measurements were iteratively compared to identify quantitative spectral similarity between the measured data and modeled outputs. Several spectral angles between the predicted and measured emissivities differed by less than 1 degree. Synthetic radiance spectra produced from the microDIRSIG/DIRSIG combination had a RMS error of 0.21-0.81 watts/(m2-sr-μm) when compared to the D&P measurements. Results from this comparison will facilitate improved methods for identifying spectral features and detecting liquid contamination on a variety of natural surfaces.
Gonioreflectometric properties of metal surfaces
NASA Astrophysics Data System (ADS)
Jaanson, P.; Manoocheri, F.; Mäntynen, H.; Gergely, M.; Widlowski, J.-L.; Ikonen, E.
2014-12-01
Angularly resolved measurements of scattered light from surfaces can provide useful information in various fields of research and industry, such as computer graphics, satellite based Earth observation etc. In practice, empirical or physics-based models are needed to interpolate the measurement results, because a thorough characterization of the surfaces under all relevant conditions may not be feasible. In this work, plain and anodized metal samples were prepared and measured optically for bidirectional reflectance distribution function (BRDF) and mechanically for surface roughness. Two models for BRDF (Torrance-Sparrow model and a polarimetric BRDF model) were fitted to the measured values. A better fit was obtained for plain metal surfaces than for anodized surfaces.
Legleiter, Carl; Mobley, Curtis D.; Overstreet, Brandon
2017-01-01
This paper introduces a framework for examining connections between the flow field, the texture of the air-water interface, and the reflectance of the water surface and thus evaluating the potential to infer hydraulic information from remotely sensed observations of surface reflectance. We used a spatial correlation model describing water surface topography to illustrate the application of our framework. Nondimensional relations between model parameters and flow intensity were established based on a prior flume study. Expressing the model in the spatial frequency domain allowed us to use an efficient Fourier transform-based algorithm for simulating water surfaces. Realizations for both flume and field settings had water surface slope distributions positively correlated with velocity and water surface roughness. However, most surface facets were gently sloped and thus unlikely to yield strong specular reflections; the model exaggerated the extent of water surface features, leading to underestimation of facet slopes. A ray tracing algorithm indicated that reflectance was greatest when solar and view zenith angles were equal and the sensor scanned toward the Sun to capture specular reflections of the solar beam. Reflected energy was concentrated in a small portion of the sky, but rougher water surfaces reflected rays into a broader range of directions. Our framework facilitates flight planning to avoid surface-reflected radiance while mapping other river attributes, or to maximize this component to exploit relationships between hydraulics and surface reflectance. This initial analysis also highlighted the need for improved models of water surface topography in natural rivers.
Inversion of Surface-wave Dispersion Curves due to Low-velocity-layer Models
NASA Astrophysics Data System (ADS)
Shen, C.; Xia, J.; Mi, B.
2016-12-01
A successful inversion relies on exact forward modeling methods. It is a key step to accurately calculate multi-mode dispersion curves of a given model in high-frequency surface-wave (Rayleigh wave and Love wave) methods. For normal models (shear (S)-wave velocity increasing with depth), their theoretical dispersion curves completely match the dispersion spectrum that is generated based on wave equation. For models containing a low-velocity-layer, however, phase velocities calculated by existing forward-modeling algorithms (e.g. Thomson-Haskell algorithm, Knopoff algorithm, fast vector-transfer algorithm and so on) fail to be consistent with the dispersion spectrum at a high frequency range. They will approach a value that close to the surface-wave velocity of the low-velocity-layer under the surface layer, rather than that of the surface layer when their corresponding wavelengths are short enough. This phenomenon conflicts with the characteristics of surface waves, which results in an erroneous inverted model. By comparing the theoretical dispersion curves with simulated dispersion energy, we proposed a direct and essential solution to accurately compute surface-wave phase velocities due to low-velocity-layer models. Based on the proposed forward modeling technique, we can achieve correct inversion for these types of models. Several synthetic data proved the effectiveness of our method.
NASA Technical Reports Server (NTRS)
Bosilovich, Michael G.; Yang, Runhua; Houser, Paul R.
1998-01-01
Land surface hydrology for the Off-line Land-surface GEOS Analysis (OLGA) system and Goddard Earth Observing System (GEOS-1) Data Assimilation System (DAS) has been examined using a river routing model. The GEOS-1 DAS land-surface parameterization is very simple, using an energy balance prediction of surface temperature and prescribed soil water. OLGA uses near-surface atmospheric data from the GEOS-1 DAS to drive a more comprehensive parameterization of the land-surface physics. The two global systems are evaluated using a global river routing model. The river routing model uses climatologic surface runoff from each system to simulate the river discharge from global river basins, which can be compared to climatologic river discharge. Due to the soil hydrology, the OLGA system shows a general improvement in the simulation of river discharge compared to the GEOS-1 DAS. Snowmelt processes included in OLGA also have a positive effect on the annual cycle of river discharge and source runoff. Preliminary tests of a coupled land-atmosphere model indicate improvements to the hydrologic cycle compared to the uncoupled system. The river routing model has provided a useful tool in the evaluation of the GCM hydrologic cycle, and has helped quantify the influence of the more advanced land surface model.
Surface tension modelling of liquid Cd-Sn-Zn alloys
NASA Astrophysics Data System (ADS)
Fima, Przemyslaw; Novakovic, Rada
2018-06-01
The thermodynamic model in conjunction with Butler equation and the geometric models were used for the surface tension calculation of Cd-Sn-Zn liquid alloys. Good agreement was found between the experimental data for limiting binaries and model calculations performed with Butler model. In the case of ternary alloys, the surface tension variation with Cd content is better reproduced in the case of alloys lying on vertical sections defined by high Sn to Zn molar fraction ratio. The calculated surface tension is in relatively good agreement with the available experimental data. In addition, the surface segregation of liquid ternary Cd-Sn-Zn and constituent binaries has also been calculated.
High resolution modelling and observation of wind-driven surface currents in a semi-enclosed estuary
NASA Astrophysics Data System (ADS)
Nash, S.; Hartnett, M.; McKinstry, A.; Ragnoli, E.; Nagle, D.
2012-04-01
Hydrodynamic circulation in estuaries is primarily driven by tides, river inflows and surface winds. While tidal and river data can be quite easily obtained for input to hydrodynamic models, sourcing accurate surface wind data is problematic. Firstly, the wind data used in hydrodynamic models is usually measured on land and can be quite different in magnitude and direction from offshore winds. Secondly, surface winds are spatially-varying but due to a lack of data it is common practice to specify a non-varying wind speed and direction across the full extents of a model domain. These problems can lead to inaccuracies in the surface currents computed by three-dimensional hydrodynamic models. In the present research, a wind forecast model is coupled with a three-dimensional numerical model of Galway Bay, a semi-enclosed estuary on the west coast of Ireland, to investigate the effect of surface wind data resolution on model accuracy. High resolution and low resolution wind fields are specified to the model and the computed surface currents are compared with high resolution surface current measurements obtained from two high frequency SeaSonde-type Coastal Ocean Dynamics Applications Radars (CODAR). The wind forecast models used for the research are Harmonie cy361.3, running on 2.5 and 0.5km spatial grids for the low resolution and high resolution models respectively. The low-resolution model runs over an Irish domain on 540x500 grid points with 60 vertical levels and a 60s timestep and is driven by ECMWF boundary conditions. The nested high-resolution model uses 300x300 grid points on 60 vertical levels and a 12s timestep. EFDC (Environmental Fluid Dynamics Code) is used for the hydrodynamic model. The Galway Bay model has ten vertical layers and is resolved spatially and temporally at 150m and 4 sec respectively. The hydrodynamic model is run for selected hindcast dates when wind fields were highly energetic. Spatially- and temporally-varying wind data is provided by offline coupling with the wind forecast models. Modelled surface currents show good correlation with CODAR observed currents and the resolution of the surface wind data is shown to be important for model accuracy.
Bourdillon, Pierre; Apra, Caroline; Lévêque, Marc
2018-03-01
Although attempts to develop stereotactic approaches to intracranial surgery started in the late 19th century with Dittmar, Zernov, and more famously, Horsley and Clarke, widespread use of the technique for human brain surgery started in the second part of the 20th century. Remarkably, a significant similar surgical procedure had already been performed in the late 19th century by Gaston Contremoulins in France and has remained unknown. Contremoulins used the principles of modern stereotaxy in association with radiography for the first time, allowing the successful removal of intracranial bullets in 2 patients. This surgical premiere, greatly acknowledged in the popular French newspaper L'Illustration in 1897, received little scientific or governmental interest at the time, as it emanated from a young self-taught scientist without official medical education. This surgical innovation was only made possible financially by popular crowdfunding and, despite widespread military use during World War I, with 37,780 patients having benefited from this technique for intra- or extracranial foreign bodies, it never attracted academic or neurosurgical consideration. The authors of this paper describe the historical context of stereotactic developments and the personal history of Contremoulins, who worked in the department of experimental physiology of the French Academy of Sciences led by Étienne-Jules Marey in Paris, and later devoted himself to radiography and radioprotection. The authors also give precise information about his original stereotactic tool "the bullet finder" ("le chercheur de projectiles") and its key concepts.
Key Challenges and New Trends in Battery Research (2011 EFRC Forum)
Tarascon, Jean Marie
2018-02-13
Jean-Marie Tarascon, Professor at the University de Picardie Jules Verne, France, was the fourth speaker in the May 26, 2011 EFRC Forum session, "Global Perspectives on Frontiers in Energy Research." In his presentation, Professor Tarascon recounted European basic research activates in electrical energy storage. The 2011 EFRC Summit and Forum brought together the EFRC community and science and policy leaders from universities, national laboratories, industry and government to discuss "Science for our Nation's Energy Future." In August 2009, the Office of Science established 46 Energy Frontier Research Centers. The EFRCs are collaborative research efforts intended to accelerate high-risk, high-reward fundamental research, the scientific basis for transformative energy technologies of the future. These Centers involve universities, national laboratories, nonprofit organizations, and for-profit firms, singly or in partnerships, selected by scientific peer review. They are funded at $2 to $5 million per year for a total planned DOE commitment of $777 million over the initial five-year award period, pending Congressional appropriations. These integrated, multi-investigator Centers are conducting fundamental research focusing on one or more of several âgrand challengesâ and use-inspired âbasic research needsâ recently identified in major strategic planning efforts by the scientific community. The purpose of the EFRCs is to integrate the talents and expertise of leading scientists in a setting designed to accelerate research that transforms the future of energy and the environment.
Wang, Shi; Bao, Zhenmin; Hu, Xiaoli; Shao, Mingyu; Zhang, Lingling; Hu, Jingjie
2008-05-01
Two novel elements (CFG1 and PYG1) of Mag lineage of Ty3/Gypsy retrotransposons were cloned from Zhikong scallop (Chlamys farreri) and Japanese scallop (Patinopecten yessoensis). The total length of the CFG1 element is 4826 bp, including 5'-LTR (192 bp), the entire ORF (4047 bp) and 3'-LTR (189 bp). The entire ORFs of both CFG1 and PYG1 elements are composed of 1348 aa and do not have any frameshifts. Their closest relative is Jule element from the poeciliid fish (Xiphophorus maculatus). On average, the diploid genome of C. farreri contains approximately 84 copies of CFG1 elements. We summarize the major features of CFG1, PYG1 and other elements of Mag lineage of the Ty3/Gypsy group. mRNA expression of CFG1 element in larvae increases gradually before the gastrulae stage and decreases gradually afterward, whereas in adductor such expression in adductor muscle and digestive gland are lower than those in other tissues. Overall, mRNA expression of CFG1 element in the early larvae is significantly higher than that in adult tissues. In muscle tissue, while the promoter and partial GAG domain of CFG1 element are unmethylated, the partial RT domain is highly methylated. These results suggest that CFG1 expression may be controlled by a post-transcriptional gene silencing mechanism that is associated with coding-region (RT domain) methylation.
[Pharmacy, one of the emerging sources of new science of technology].
Charlot, Colette
2015-01-01
Linking pharmacy and oenology seems to be paradox. The school of Medicine and Pharmacy owe their fame to the historical context of the Languedocian Universities. The role of their naturalist professors is less known. Dr Chaptal's thesis discusses the wine chemical constituents. In 1801 he published a book entitled "the Art of making, managing and perfecting wine", inventor of a distillation machine, his name become an eponym "the chaptalisation", which is specific process, for regions less exposed to sunlight, showing that sugar in the must is needed to obtain alcohol. Jules Emile Planchon, professor of botanic science at the Superior School of Pharmacy will discoverer the parasite disease of the phylloxera, a parasite that destroy vineyards. The cure will be the American grafting. The list of professors who worked on vineyards related frauds and diseases is long. Once Analytical chemistry has become part of the curriculum universities, pharmacists, started investigating wine analysis. It will be part of Bromatology, the science of food ingredients. Pharmacists were then able to carry out the first wine analyses sin their laboratory. It is at that time that Paul Jaulmes, professor of Analytical Chemistry who became Director of the international office of vineyards and Wine (OIV) proposed alongside Prof Nègre, director of the National School of Agronomy, the initiation in 1955 of a new diploma oenology. As a renowned toxicologist, Prof. Jaulmes will lead the committee in charge of the oenology Standards.
Bacterial keratitis: a prospective clinical and microbiological study
Schaefer, F.; Bruttin, O.; Zografos, L.; Guex-Crosier, Y.
2001-01-01
AIM—To define the clinical and microbiological profile of bacterial keratitis at the Jules Gonin Eye Hospital and to test the in vitro bacterial resistance. METHODS—Patients presenting with bacterial keratitis were prospectively followed; clinical features (age, risk factors, visual acuity) and response to therapy were analysed. Bacteriological profile was determined and the sensitivity/resistance of isolated strains were tested towards 12 ocular antibiotics (NCCLS disc diffusion test). RESULTS—85 consecutive patients (mean age 44.3 (SD 20.7) years) were prospectively enrolled from 1 March 1997 to 30 November 1998. The following risk factors were identified: contact lens wear, 36%; blepharitis, 21%; trauma, 20%; xerophthalmia, 15%; keratopathies, 8%; and eyelid abnormalities, 6%. The most commonly isolated bacteria were Staphylococcus epidermidis, 40%; Staphylococcus aureus, 22%; Streptococcus pneumoniae, 8%; others Streptococcus species, 5%; Pseudomonas, 9%; Moraxella and Serratia marcescens, 5% each; Bacillus, Corynebacterium, Alcaligenes xyloxidans, Morganella morganii, and Haemophilus influenza, 1% each. 1-15% of strains were resistant to fluoroquinolones, 13-22% to aminoglycosides, 37% to cefazolin, 18% to chloramphenicol, 54% to polymyxin B, 51% to fusidic acid, and 45% to bacitracin. Five of the 85 patients (5.8%) had a poor clinical outcome with a visual loss of one or more lines of visual acuity. CONCLUSION—Fluoroquinolones appear to be the therapy of choice for bacterial keratitis, but, based upon these in vitro studies, some strains may be resistant. PMID:11423460
NASA Astrophysics Data System (ADS)
Osterbrock, D. E.
1999-05-01
Growing up in Chicago, George Ellery Hale, later the prime spirit in founding the AAS, was a precocious boy scientist. He was deeply interested in spectroscopy and astrophysics from an early age. His wealthy parents encouraged Hale's aspirations with magazines, books, and instruments, and he acquired his first telescope when he was 14. He knew as mentors classical astronomers S. W. Burnham and George W. Hough, but he preferred astrophysics and designed his own Kenwood Physical Obseervatory around a grating in a Rowland circle mounting, fed by a heliostat, both built for him by instrument-maker John A. Brashear. For his undergraduate thesis at MIT, Hale invented and (at Harvard College Observatory) demonstrated the spectroheliograph. With it, and a high-quality 12-in refractor at his later Kenwood Astrophysical Observatory (at the same site, the Hale family home, 4 miles from the present Hilton Hotel where the SPD, HAD and AAS are meeting) Hale did excellent solar research, especially on promineneces, flocculi, and the near-ultraviolet spectrum of the chromosphere. As a teen-ager and a young adult Hale traveled widely, and met several important piuoneer solar physicists, including Charles A. Young, Jules Janssen, Samuel P. Langley, and Henry Rowland. Hale designed Yerkes Observatory for solar and stellar research, and headed the solar work himself. One of his aims always was to compare other stars with the sun. Hale's telescopes, instruments, methods, and resulting papers will be described and illustrated by numerous slides.
NASA Astrophysics Data System (ADS)
Widodo, Edy; Kariyam
2017-03-01
To determine the input variable settings that create the optimal compromise in response variable used Response Surface Methodology (RSM). There are three primary steps in the RSM problem, namely data collection, modelling, and optimization. In this study focused on the establishment of response surface models, using the assumption that the data produced is correct. Usually the response surface model parameters are estimated by OLS. However, this method is highly sensitive to outliers. Outliers can generate substantial residual and often affect the estimator models. Estimator models produced can be biased and could lead to errors in the determination of the optimal point of fact, that the main purpose of RSM is not reached. Meanwhile, in real life, the collected data often contain some response variable and a set of independent variables. Treat each response separately and apply a single response procedures can result in the wrong interpretation. So we need a development model for the multi-response case. Therefore, it takes a multivariate model of the response surface that is resistant to outliers. As an alternative, in this study discussed on M-estimation as a parameter estimator in multivariate response surface models containing outliers. As an illustration presented a case study on the experimental results to the enhancement of the surface layer of aluminium alloy air by shot peening.
Mapping Land and Water Surface Topography with instantaneous Structure from Motion
NASA Astrophysics Data System (ADS)
Dietrich, J.; Fonstad, M. A.
2012-12-01
Structure from Motion (SfM) has given researchers an invaluable tool for low-cost, high-resolution 3D mapping of the environment. These SfM 3D surface models are commonly constructed from many digital photographs collected with one digital camera (either handheld or attached to aerial platform). This method works for stationary or very slow moving objects. However, objects in motion are impossible to capture with one-camera SfM. With multiple simultaneously triggered cameras, it becomes possible to capture multiple photographs at the same time which allows for the construction 3D surface models of moving objects and surfaces, an instantaneous SfM (ISfM) surface model. In river science, ISfM provides a low-cost solution for measuring a number of river variables that researchers normally estimate or are unable to collect over large areas. With ISfM and sufficient coverage of the banks and RTK-GPS control it is possible to create a digital surface model of land and water surface elevations across an entire channel and water surface slopes at any point within the surface model. By setting the cameras to collect time-lapse photography of a scene it is possible to create multiple surfaces that can be compared using traditional digital surface model differencing. These water surface models could be combined the high-resolution bathymetry to create fully 3D cross sections that could be useful in hydrologic modeling. Multiple temporal image sets could also be used in 2D or 3D particle image velocimetry to create 3D surface velocity maps of a channel. Other applications in earth science include anything where researchers could benefit from temporal surface modeling like mass movements, lava flows, dam removal monitoring. The camera system that was used for this research consisted of ten pocket digital cameras (Canon A3300) equipped with wireless triggers. The triggers were constructed with an Arduino-style microcontroller and off-the-shelf handheld radios with a maximum range of several kilometers. The cameras are controlled from another microcontroller/radio combination that allows for manual or automatic triggering of the cameras. The total cost of the camera system was approximately 1500 USD.
Spadini, Lorenzo; Schindler, Paul W; Charlet, Laurent; Manceau, Alain; Vala Ragnarsdottir, K
2003-10-01
The surface properties of ferrihydrite were studied by combining wet chemical data, Cd(K) EXAFS data, and a surface structure and protonation model of the ferrihydrite surface. Acid-base titration experiments and Cd(II)-ferrihydrite sorption experiments were performed within 3<-log[H(+)]<10.5 and 0.5<[Cd(t)]<12 mM in 0.3 M NaClO(4) at 25 degrees C, where [Cd(t)] refers to total Cd concentration. Measurements at -5.5
Surface roughness retrieval by inversion of the Hapke model: A multiscale approach
NASA Astrophysics Data System (ADS)
Labarre, S.; Ferrari, C.; Jacquemoud, S.
2017-07-01
Surface roughness is a key property of soils that controls many surface processes and influences the scattering of incident electromagnetic waves at a wide range of scales. Hapke (2012b) designed a photometric model providing an approximate analytical solution of the Bidirectional Reflectance Distribution Function (BRDF) of a particulate medium: he introduced the effect of surface roughness as a correction factor of the BRDF of a smooth surface. This photometric roughness is defined as the mean slope angle of the facets composing the surface, integrated over all scales from the grain size to the local topography. Yet its physical meaning is still a question at issue, as the scale at which it occurs is not clearly defined. This work aims at better understanding the relative influence of roughness scales on soil BRDF and to test the ability of the Hapke model to retrieve a roughness that depicts effectively the ground truth. We apply a wavelet transform on millimeter digital terrain models (DTM) acquired over volcanic terrains. This method allows splitting the frequency band of a signal in several sub-bands, each corresponding to a spatial scale. We demonstrate that sub-centimeter surface features dominate both the integrated roughness and the BRDF shape. We investigate the suitability of the Hapke model for surface roughness retrieval by inversion on optical data. A global sensitivity analysis of the model shows that soil BRDF is very sensitive to surface roughness, nearly as much as the single scattering albedo according to the phase angle, but also that these two parameters are strongly correlated. Based on these results, a simplified two-parameter model depending on surface albedo and roughness is proposed. Inversion of this model on BRDF data simulated by a ray-tracing code over natural targets shows a good estimation of surface roughness when the assumptions of the model are verified, with a priori knowledge on surface albedo.
Dagdeviren, Omur E
2018-08-03
The effect of surface disorder, load, and velocity on friction between a single asperity contact and a model surface is explored with one-dimensional and two-dimensional Prandtl-Tomlinson (PT) models. We show that there are fundamental physical differences between the predictions of one-dimensional and two-dimensional models. The one-dimensional model estimates a monotonic increase in friction and energy dissipation with load, velocity, and surface disorder. However, a two-dimensional PT model, which is expected to approximate a tip-sample system more realistically, reveals a non-monotonic trend, i.e. friction is inert to surface disorder and roughness in wearless friction regime. The two-dimensional model discloses that the surface disorder starts to dominate the friction and energy dissipation when the tip and the sample interact predominantly deep into the repulsive regime. Our numerical calculations address that tracking the minimum energy path and the slip-stick motion are two competing effects that determine the load, velocity, and surface disorder dependence of friction. In the two-dimensional model, the single asperity can follow the minimum energy path in wearless regime; however, with increasing load and sliding velocity, the slip-stick movement dominates the dynamic motion and results in an increase in friction by impeding tracing the minimum energy path. Contrary to the two-dimensional model, when the one-dimensional PT model is employed, the single asperity cannot escape to the minimum energy minimum due to constraint motion and reveals only a trivial dependence of friction on load, velocity, and surface disorder. Our computational analyses clarify the physical differences between the predictions of the one-dimensional and two-dimensional models and open new avenues for disordered surfaces for low energy dissipation applications in wearless friction regime.
Beam-tracing model for predicting sound fields in rooms with multilayer bounding surfaces
NASA Astrophysics Data System (ADS)
Wareing, Andrew; Hodgson, Murray
2005-10-01
This paper presents the development of a wave-based room-prediction model for predicting steady-state sound fields in empty rooms with specularly reflecting, multilayer surfaces. A triangular beam-tracing model with phase, and a transfer-matrix approach to model the surfaces, were involved. Room surfaces were modeled as multilayers of fluid, solid, or porous materials. Biot theory was used in the transfer-matrix formulation of the porous layer. The new model consisted of the transfer-matrix model integrated into the beam-tracing algorithm. The transfer-matrix model was validated by comparing predictions with those by theory, and with experiment. The test surfaces were a glass plate, double drywall panels, double steel panels, a carpeted floor, and a suspended-acoustical ceiling. The beam-tracing model was validated in the cases of three idealized room configurations-a small office, a corridor, and a small industrial workroom-with simple boundary conditions. The number of beams, the reflection order, and the frequency resolution required to obtain accurate results were investigated. Beam-tracing predictions were compared with those by a method-of-images model with phase. The model will be used to study sound fields in rooms with local- or extended-reaction multilayer surfaces.
Advances in land modeling of KIAPS based on the Noah Land Surface Model
NASA Astrophysics Data System (ADS)
Koo, Myung-Seo; Baek, Sunghye; Seol, Kyung-Hee; Cho, Kyoungmi
2017-08-01
As of 2013, the Noah Land Surface Model (LSM) version 2.7.1 was implemented in a new global model being developed at the Korea Institute of Atmospheric Prediction Systems (KIAPS). This land surface scheme is further refined in two aspects, by adding new physical processes and by updating surface input parameters. Thus, the treatment of glacier land, sea ice, and snow cover are addressed more realistically. Inconsistencies in the amount of absorbed solar flux at ground level by the land surface and radiative processes are rectified. In addition, new parameters are available by using 1-km land cover data, which had usually not been possible at a global scale. Land surface albedo/emissivity climatology is newly created using Moderate-Resolution Imaging Spectroradiometer (MODIS) satellitebased data and adjusted parameterization. These updates have been applied to the KIAPS-developed model and generally provide a positive impact on near-surface weather forecasting.
Two-Layer Variable Infiltration Capacity Land Surface Representation for General Circulation Models
NASA Technical Reports Server (NTRS)
Xu, L.
1994-01-01
A simple two-layer variable infiltration capacity (VIC-2L) land surface model suitable for incorporation in general circulation models (GCMs) is described. The model consists of a two-layer characterization of the soil within a GCM grid cell, and uses an aerodynamic representation of latent and sensible heat fluxes at the land surface. The effects of GCM spatial subgrid variability of soil moisture and a hydrologically realistic runoff mechanism are represented in the soil layers. The model was tested using long-term hydrologic and climatalogical data for Kings Creek, Kansas to estimate and validate the hydrological parameters. Surface flux data from three First International Satellite Land Surface Climatology Project Field Experiments (FIFE) intensive field compaigns in the summer and fall of 1987 in central Kansas, and from the Anglo-Brazilian Amazonian Climate Observation Study (ABRACOS) in Brazil were used to validate the mode-simulated surface energy fluxes and surface temperature.
A structural model for surface-enhanced stabilization in some metallic glass formers
NASA Astrophysics Data System (ADS)
Levchenko, Elena V.; Evteev, Alexander V.; Yavari, Alain R.; Louzguine-Luzgin, Dmitri V.; Belova, Irina V.; Murch, Graeme E.
2013-01-01
A structural model for surface-enhanced stabilization in some metallic glass formers is proposed. In this model, the alloy surface structure is represented by five-layer Kagomé-net-based lateral ordering. Such surface structure has intrinsic abilities to stabilize icosahedral-like short-range order in the bulk, acting as 'a cloak of liquidity'. In particular, recent experimental observations of surface-induced lateral ordering and a very high glass forming ability of the liquid alloy Au49Ag5.5Pd2.3Cu26.9Si16.3 can be united using this structural model. This model may be useful for the interpretation of surface structure of other liquid alloys with a high glass forming ability. In addition, it suggests the possibility of guiding the design of the surface coating of solid containers for the stabilization of undercooled liquids.
Preliminary assessment of soil moisture over vegetation
NASA Technical Reports Server (NTRS)
Carlson, T. N.
1986-01-01
Modeling of surface energy fluxes was combined with in-situ measurement of surface parameters, specifically the surface sensible heat flux and the substrate soil moisture. A vegetation component was incorporated in the atmospheric/substrate model and subsequently showed that fluxes over vegetation can be very much different than those over bare soil for a given surface-air temperature difference. The temperature signatures measured by a satellite or airborne radiometer should be interpreted in conjunction with surface measurements of modeled parameters. Paradoxically, analyses of the large-scale distribution of soil moisture availability shows that there is a very high correlation between antecedent precipitation and inferred surface moisture availability, even when no specific vegetation parameterization is used in the boundary layer model. Preparatory work was begun in streamlining the present boundary layer model, developing better algorithms for relating surface temperatures to substrate moisture, preparing for participation in the French HAPEX experiment, and analyzing aircraft microwave and radiometric surface temperature data for the 1983 French Beauce experiments.
The acid-base titration of montmorillonite
NASA Astrophysics Data System (ADS)
Bourg, I. C.; Sposito, G.; Bourg, A. C.
2003-12-01
Proton binding to clay minerals plays an important role in the chemical reactivity of soils (e.g., acidification, retention of nutrients or pollutants). If should also affect the performance of clay barriers for waste disposal. The surface acidity of clay minerals is commonly modelled empirically by assuming generic amphoteric surface sites (>SOH) on a flat surface, with fitted site densities and acidity constant. Current advances in experimental methods (notably spectroscopy) are rapidly improving our understanding of the structure and reactivity of the surface of clay minerals (arrangement of the particles, nature of the reactive surface sites, adsorption mechanisms). These developments are motivated by the difficulty of modelling the surface chemistry of mineral surfaces at the macro-scale (e.g., adsorption or titration) without a detailed (molecular-scale) picture of the mechanisms, and should be progressively incorporated into surface complexation models. In this view, we have combined recent estimates of montmorillonite surface properties (surface site density and structure, edge surface area, surface electrostatic potential) with surface site acidities obtained from the titration of alpha-Al2O3 and SiO2, and a novel method of accounting for the unknown initial net proton surface charge of the solid. The model predictions were compared to experimental titrations of SWy-1 montmorillonite and purified MX-80 bentonite in 0.1-0.5 mol/L NaClO4 and 0.005-0.5 mol/L NaNO3 background electrolytes, respectively. Most of the experimental data were appropriately described by the model after we adjusted a single parameter (silanol sites on the surface of montmorillonite were made to be slightly more acidic than those of silica). At low ionic strength and acidic pH the model underestimated the buffering capacity of the montmorillonite, perhaps due to clay swelling or to the interlayer adsorption of dissolved aluminum. The agreement between our model and the experimental data illustrates the complementarity of molecular and macro-scale descriptions of the clay reactivity.
Control surface in aerial triangulation
NASA Astrophysics Data System (ADS)
Jaw, Jen-Jer
With the increased availability of surface-related sensors, the collection of surface information becomes easier and more straightforward than ever before. In this study, the author proposes a model in which the surface information is integrated into the aerial triangulation workflow by hypothesizing plane observations in the object space, the estimated object points via photo measurements (or matching) together with the adjusted surface points would provide a better point group describing the surface. The algorithms require no special structure of surface points and involve no interpolation process. The suggested measuring strategy (pairwise measurements) results in a quite fluent and favorable working environment when taking measurements. Furthermore, the extension of the model employing the the surface plane finds itself useful in tying photo models. The proposed model has been proven working by the simulation and carried out in the photogrammetric laboratory.
Modeling the growth of Listeria monocytogenes on the surface of smear- or mold-ripened cheese.
Schvartzman, M Sol; Gonzalez-Barron, Ursula; Butler, Francis; Jordan, Kieran
2014-01-01
Surface-ripened cheeses are matured by means of manual or mechanical technologies posing a risk of cross-contamination, if any cheeses are contaminated with Listeria monocytogenes. In predictive microbiology, primary models are used to describe microbial responses, such as growth rate over time and secondary models explain how those responses change with environmental factors. In this way, primary models were used to assess the growth rate of L. monocytogenes during ripening of the cheeses and the secondary models to test how much the growth rate was affected by either the pH and/or the water activity (aw) of the cheeses. The two models combined can be used to predict outcomes. The purpose of these experiments was to test three primary (the modified Gompertz equation, the Baranyi and Roberts model, and the Logistic model) and three secondary (the Cardinal model, the Ratowski model, and the Presser model) mathematical models in order to define which combination of models would best predict the growth of L. monocytogenes on the surface of artificially contaminated surface-ripened cheeses. Growth on the surface of the cheese was assessed and modeled. The primary models were firstly fitted to the data and the effects of pH and aw on the growth rate (μmax) were incorporated and assessed one by one with the secondary models. The Logistic primary model by itself did not show a better fit of the data among the other primary models tested, but the inclusion of the Cardinal secondary model improved the final fit. The aw was not related to the growth of Listeria. This study suggests that surface-ripened cheese should be separately regulated within EU microbiological food legislation and results expressed as counts per surface area rather than per gram.
Modeling Surface Roughness to Estimate Surface Moisture Using Radarsat-2 Quad Polarimetric SAR Data
NASA Astrophysics Data System (ADS)
Nurtyawan, R.; Saepuloh, A.; Budiharto, A.; Wikantika, K.
2016-08-01
Microwave backscattering from the earth's surface depends on several parameters such as surface roughness and dielectric constant of surface materials. The two parameters related to water content and porosity are crucial for estimating soil moisture. The soil moisture is an important parameter for ecological study and also a factor to maintain energy balance of land surface and atmosphere. Direct roughness measurements to a large area require extra time and cost. Heterogeneity roughness scale for some applications such as hydrology, climate, and ecology is a problem which could lead to inaccuracies of modeling. In this study, we modeled surface roughness using Radasat-2 quad Polarimetric Synthetic Aperture Radar (PolSAR) data. The statistical approaches to field roughness measurements were used to generate an appropriate roughness model. This modeling uses a physical SAR approach to predicts radar backscattering coefficient in the parameter of radar configuration (wavelength, polarization, and incidence angle) and soil parameters (surface roughness and dielectric constant). Surface roughness value is calculated using a modified Campbell and Shepard model in 1996. The modification was applied by incorporating the backscattering coefficient (σ°) of quad polarization HH, HV and VV. To obtain empirical surface roughness model from SAR backscattering intensity, we used forty-five sample points from field roughness measurements. We selected paddy field in Indramayu district, West Java, Indonesia as the study area. This area was selected due to intensive decreasing of rice productivity in the Northern Coast region of West Java. Third degree polynomial is the most suitable data fitting with coefficient of determination R2 and RMSE are about 0.82 and 1.18 cm, respectively. Therefore, this model is used as basis to generate the map of surface roughness.
NASA Astrophysics Data System (ADS)
Liu, Yongqiang; Mamtimin, Ali; He, Qing
2014-05-01
Because land surface emissivity (ɛ) has not been reliably measured, global climate model (GCM) land surface schemes conventionally set this parameter as simply assumption, for example, 1 as in the National Oceanic and Atmospheric Administration (NOAA) National Centers for Environmental Prediction (NCEP) model, 0.96 for soil and wetland in the Global and Regional Assimilation and Prediction System (GRAPES) Common Land Model (CoLM). This is the so-called emissivity assumption. Accurate broadband emissivity data are needed as model inputs to better simulate the land surface climate. It is demonstrated in this paper that the assumption of the emissivity induces errors in modeling the surface energy budget over Taklimakan Desert where ɛ is far smaller than original value. One feasible solution to this problem is to apply the accurate broadband emissivity into land surface models. The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument has routinely measured spectral emissivities in six thermal infrared bands. The empirical regression equations have been developed in this study to convert these spectral emissivities to broadband emissivity required by land surface models. In order to calibrate the regression equations, using a portable Fourier Transform infrared (FTIR) spectrometer instrument, crossing Taklimakan Desert along with highway from north to south, to measure the accurate broadband emissivity. The observed emissivity data show broadband ɛ around 0.89-0.92. To examine the impact of improved ɛ to radiative energy redistribution, simulation studies were conducted using offline CoLM. The results illustrate that large impacts of surface ɛ occur over desert, with changes up in surface skin temperature, as well as evident changes in sensible heat fluxes. Keywords: Taklimakan Desert, surface broadband emissivity, Fourier Transform infrared spectrometer, MODIS, CoLM
A CONTINUUM HARD-SPHERE MODEL OF PROTEIN ADSORPTION
Finch, Craig; Clarke, Thomas; Hickman, James J.
2012-01-01
Protein adsorption plays a significant role in biological phenomena such as cell-surface interactions and the coagulation of blood. Two-dimensional random sequential adsorption (RSA) models are widely used to model the adsorption of proteins on solid surfaces. Continuum equations have been developed so that the results of RSA simulations can be used to predict the kinetics of adsorption. Recently, Brownian dynamics simulations have become popular for modeling protein adsorption. In this work a continuum model was developed to allow the results from a Brownian dynamics simulation to be used as the boundary condition in a computational fluid dynamics (CFD) simulation. Brownian dynamics simulations were used to model the diffusive transport of hard-sphere particles in a liquid and the adsorption of the particles onto a solid surface. The configuration of the adsorbed particles was analyzed to quantify the chemical potential near the surface, which was found to be a function of the distance from the surface and the fractional surface coverage. The near-surface chemical potential was used to derive a continuum model of adsorption that incorporates the results from the Brownian dynamics simulations. The equations of the continuum model were discretized and coupled to a CFD simulation of diffusive transport to the surface. The kinetics of adsorption predicted by the continuum model closely matched the results from the Brownian dynamics simulation. This new model allows the results from mesoscale simulations to be incorporated into micro- or macro-scale CFD transport simulations of protein adsorption in practical devices. PMID:23729843
NASA Astrophysics Data System (ADS)
Han, D.; Wang, J.
2015-12-01
The moon-plasma interactions and the resulting surface charging have been subjects of extensive recent investigations. While many particle-in-cell (PIC) based simulation models have been developed, all existing PIC simulation models treat the surface of the Moon as a boundary condition to the plasma flow. In such models, the surface of the Moon is typically limited to simple geometry configurations, the surface floating potential is calculated from a simplified current balance condition, and the electric field inside the regolith layer cannot be resolved. This paper presents a new full particle PIC model to simulate local scale plasma flow and surface charging. A major feature of this new model is that the surface is treated as an "interface" between two mediums rather than a boundary, and the simulation domain includes not only the plasma but also the regolith layer and the bedrock underneath it. There are no limitations on the surface shape. An immersed-finite-element field solver is applied which calculates the regolith surface floating potential and the electric field inside the regolith layer directly from local charge deposition. The material property of the regolith layer is also explicitly included in simulation. This new model is capable of providing a self-consistent solution to the plasma flow field, lunar surface charging, the electric field inside the regolith layer and the bedrock for realistic surface terrain. This new model is applied to simulate lunar surface-plasma interactions and surface charging under various ambient plasma conditions. The focus is on the lunar terminator region, where the combined effects from the low sun elevation angle and the localized plasma wake generated by plasma flow over a rugged terrain can generate strongly differentially charged surfaces and complex dust dynamics. We discuss the effects of the regolith properties and regolith layer charging on the plasma flow field, dust levitation, and dust transport.
Chen, Ran; Riviere, Jim E
2017-01-01
Quantitative analysis of the interactions between nanomaterials and their surrounding environment is crucial for safety evaluation in the application of nanotechnology as well as its development and standardization. In this chapter, we demonstrate the importance of the adsorption of surrounding molecules onto the surface of nanomaterials by forming biocorona and thus impact the bio-identity and fate of those materials. We illustrate the key factors including various physical forces in determining the interaction happening at bio-nano interfaces. We further discuss the mathematical endeavors in explaining and predicting the adsorption phenomena, and propose a new statistics-based surface adsorption model, the Biological Surface Adsorption Index (BSAI), to quantitatively analyze the interaction profile of surface adsorption of a large group of small organic molecules onto nanomaterials with varying surface physicochemical properties, first employing five descriptors representing the surface energy profile of the nanomaterials, then further incorporating traditional semi-empirical adsorption models to address concentration effects of solutes. These Advancements in surface adsorption modelling showed a promising development in the application of quantitative predictive models in biological applications, nanomedicine, and environmental safety assessment of nanomaterials.
Extending the diffuse layer model of surface acidity behavior: I. Model development
Considerable disenchantment exists within the environmental research community concerning our current ability to accurately model surface-complexation-mediated low-porewater-concentration ionic contaminant partitioning with natural surfaces. Several authors attribute this unaccep...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yu, Miao; Wang, Guiling; Chen, Haishan
Assessing and quantifying the uncertainties in projected future changes of energy and water budgets over land surface are important steps toward improving our confidence in climate change projections. In our study, the contribution of land surface models to the inter-GCM variation of projected future changes in land surface energy and water fluxes are assessed based on output from 19 global climate models (GCMs) and offline Community Land Model version 4 (CLM4) simulations driven by meteorological forcing from the 19 GCMs. Similar offline simulations using CLM4 with its dynamic vegetation submodel are also conducted to investigate how dynamic vegetation feedback, amore » process that is being added to more earth system models, may amplify or moderate the intermodel variations of projected future changes. Projected changes are quantified as the difference between the 2081–2100 period from the Representative Concentration Pathway 8.5 (RCP8.5) future experiment and the 1981–2000 period from the historical simulation. Under RCP8.5, projected changes in surface water and heat fluxes show a high degree of model dependency across the globe. Although precipitation is very likely to increase in the high latitudes of the Northern Hemisphere, a high degree of model-related uncertainty exists for evapotranspiration, soil water content, and surface runoff, suggesting discrepancy among land surface models (LSMs) in simulating the surface hydrological processes and snow-related processes. Large model-related uncertainties for the surface water budget also exist in the Tropics including southeastern South America and Central Africa. Moreover, these uncertainties would be reduced in the hypothetical scenario of a single near-perfect land surface model being used across all GCMs, suggesting the potential to reduce uncertainties through the use of more consistent approaches toward land surface model development. Under such a scenario, the most significant reduction is likely to be seen in the Northern Hemisphere high latitudes. Including representation of vegetation dynamics is expected to further amplify the model-related uncertainties in projected future changes in surface water and heat fluxes as well as soil moisture content. This is especially the case in the high latitudes of the Northern Hemisphere (e.g., northwestern North America and central North Asia) where the projected vegetation changes are uncertain and in the Tropics (e.g., the Amazon and Congo Basins) where dense vegetation exists. Finally, findings from this study highlight the importance of improving land surface model parameterizations related to soil and snow processes, as well as the importance of improving the accuracy of dynamic vegetation models.« less
Yu, Miao; Wang, Guiling; Chen, Haishan
2016-03-01
Assessing and quantifying the uncertainties in projected future changes of energy and water budgets over land surface are important steps toward improving our confidence in climate change projections. In our study, the contribution of land surface models to the inter-GCM variation of projected future changes in land surface energy and water fluxes are assessed based on output from 19 global climate models (GCMs) and offline Community Land Model version 4 (CLM4) simulations driven by meteorological forcing from the 19 GCMs. Similar offline simulations using CLM4 with its dynamic vegetation submodel are also conducted to investigate how dynamic vegetation feedback, amore » process that is being added to more earth system models, may amplify or moderate the intermodel variations of projected future changes. Projected changes are quantified as the difference between the 2081–2100 period from the Representative Concentration Pathway 8.5 (RCP8.5) future experiment and the 1981–2000 period from the historical simulation. Under RCP8.5, projected changes in surface water and heat fluxes show a high degree of model dependency across the globe. Although precipitation is very likely to increase in the high latitudes of the Northern Hemisphere, a high degree of model-related uncertainty exists for evapotranspiration, soil water content, and surface runoff, suggesting discrepancy among land surface models (LSMs) in simulating the surface hydrological processes and snow-related processes. Large model-related uncertainties for the surface water budget also exist in the Tropics including southeastern South America and Central Africa. Moreover, these uncertainties would be reduced in the hypothetical scenario of a single near-perfect land surface model being used across all GCMs, suggesting the potential to reduce uncertainties through the use of more consistent approaches toward land surface model development. Under such a scenario, the most significant reduction is likely to be seen in the Northern Hemisphere high latitudes. Including representation of vegetation dynamics is expected to further amplify the model-related uncertainties in projected future changes in surface water and heat fluxes as well as soil moisture content. This is especially the case in the high latitudes of the Northern Hemisphere (e.g., northwestern North America and central North Asia) where the projected vegetation changes are uncertain and in the Tropics (e.g., the Amazon and Congo Basins) where dense vegetation exists. Finally, findings from this study highlight the importance of improving land surface model parameterizations related to soil and snow processes, as well as the importance of improving the accuracy of dynamic vegetation models.« less
The impact of surface area, volume, curvature, and Lennard-Jones potential to solvation modeling.
Nguyen, Duc D; Wei, Guo-Wei
2017-01-05
This article explores the impact of surface area, volume, curvature, and Lennard-Jones (LJ) potential on solvation free energy predictions. Rigidity surfaces are utilized to generate robust analytical expressions for maximum, minimum, mean, and Gaussian curvatures of solvent-solute interfaces, and define a generalized Poisson-Boltzmann (GPB) equation with a smooth dielectric profile. Extensive correlation analysis is performed to examine the linear dependence of surface area, surface enclosed volume, maximum curvature, minimum curvature, mean curvature, and Gaussian curvature for solvation modeling. It is found that surface area and surfaces enclosed volumes are highly correlated to each other's, and poorly correlated to various curvatures for six test sets of molecules. Different curvatures are weakly correlated to each other for six test sets of molecules, but are strongly correlated to each other within each test set of molecules. Based on correlation analysis, we construct twenty six nontrivial nonpolar solvation models. Our numerical results reveal that the LJ potential plays a vital role in nonpolar solvation modeling, especially for molecules involving strong van der Waals interactions. It is found that curvatures are at least as important as surface area or surface enclosed volume in nonpolar solvation modeling. In conjugation with the GPB model, various curvature-based nonpolar solvation models are shown to offer some of the best solvation free energy predictions for a wide range of test sets. For example, root mean square errors from a model constituting surface area, volume, mean curvature, and LJ potential are less than 0.42 kcal/mol for all test sets. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
A microscale three-dimensional urban energy balance model for studying surface temperatures
NASA Astrophysics Data System (ADS)
Krayenhoff, E. Scott; Voogt, James A.
2007-06-01
A microscale three-dimensional (3-D) urban energy balance model, Temperatures of Urban Facets in 3-D (TUF-3D), is developed to predict urban surface temperatures for a variety of surface geometries and properties, weather conditions, and solar angles. The surface is composed of plane-parallel facets: roofs, walls, and streets, which are further sub-divided into identical square patches, resulting in a 3-D raster-type model geometry. The model code is structured into radiation, conduction and convection sub-models. The radiation sub-model uses the radiosity approach and accounts for multiple reflections and shading of direct solar radiation. Conduction is solved by finite differencing of the heat conduction equation, and convection is modelled by empirically relating patch heat transfer coefficients to the momentum forcing and the building morphology. The radiation and conduction sub-models are tested individually against measurements, and the complete model is tested against full-scale urban surface temperature and energy balance observations. Modelled surface temperatures perform well at both the facet-average and the sub-facet scales given the precision of the observations and the uncertainties in the model inputs. The model has several potential applications, such as the calculation of radiative loads, and the investigation of effective thermal anisotropy (when combined with a sensor-view model).
Validation of Atmospheric Forcing Data for PIPS 3
2001-09-30
members shortly. RESULTS Surface Temperature: Figure 1 shows a comparison of surface air temperatures from the NOGAPS model , the IABP and the NCEP...with some 8,000 daily velocity observations from the IABP buoys shows that the sea-ice model performs better when driven with NOGAPS surface stresses...forcing variables, surface radiative fluxes, surface winds, and precipitation estimates to be used in the development and operation of the PIPS 3.0 model
NASA Technical Reports Server (NTRS)
Lynn, Barry H.; Stauffer, David R.; Wetzel, Peter J.; Tao, Wei-Kuo; Perlin, Natal; Baker, R. David; Munoz, Ricardo; Boone, Aaron; Jia, Yiqin
1999-01-01
A sophisticated land-surface model, PLACE, the Parameterization for Land Atmospheric Convective Exchange, has been coupled to a 1.5-order turbulent kinetic energy (TKE) turbulence sub-model. Both have been incorporated into the Penn State/National Center for Atmospheric Research (PSU/NCAR) mesoscale model MM5. Such model improvements should have their greatest effect in conditions where surface contrasts dominate over dynamic processes, such as the simulation of warm-season, convective events. A validation study used the newly coupled model, MM5 TKE-PLACE, to simulate the evolution of Florida sea-breeze moist convection during the Convection and Precipitation Electrification Experiment (CaPE). Overall, eight simulations tested the sensitivity of the MM5 model to combinations of the new and default model physics, and initialization of soil moisture and temperature. The TKE-PLACE model produced more realistic surface sensible heat flux, lower biases for surface variables, more realistic rainfall, and cloud cover than the default model. Of the 8 simulations with different factors (i.e., model physics or initialization), TKE-PLACE compared very well when each simulation was ranked in terms of biases of the surface variables and rainfall, and percent and root mean square of cloud cover. A factor separation analysis showed that a successful simulation required the inclusion of a multi-layered, land surface soil vegetation model, realistic initial soil moisture, and higher order closure of the planetary boundary layer (PBL). These were needed to realistically model the effect of individual, joint, and synergistic contributions from the land surface and PBL on the CAPE sea-breeze, Lake Okeechobee lake breeze, and moist convection.
Application of IEM model on soil moisture and surface roughness estimation
NASA Technical Reports Server (NTRS)
Shi, Jiancheng; Wang, J. R.; Oneill, P. E.; Hsu, A. Y.; Engman, E. T.
1995-01-01
Monitoring spatial and temporal changes of soil moisture are of importance to hydrology, meteorology, and agriculture. This paper reports a result on study of using L-band SAR imagery to estimate soil moisture and surface roughness for bare fields. Due to limitations of the Small Perturbation Model, it is difficult to apply this model on estimation of soil moisture and surface roughness directly. In this study, we show a simplified model derived from the Integral Equation Model for estimation of soil moisture and surface roughness. We show a test of this model using JPL L-band AIRSAR data.
High-resolution surface analysis for extended-range downscaling with limited-area atmospheric models
NASA Astrophysics Data System (ADS)
Separovic, Leo; Husain, Syed Zahid; Yu, Wei; Fernig, David
2014-12-01
High-resolution limited-area model (LAM) simulations are frequently employed to downscale coarse-resolution objective analyses over a specified area of the globe using high-resolution computational grids. When LAMs are integrated over extended time frames, from months to years, they are prone to deviations in land surface variables that can be harmful to the quality of the simulated near-surface fields. Nudging of the prognostic surface fields toward a reference-gridded data set is therefore devised in order to prevent the atmospheric model from diverging from the expected values. This paper presents a method to generate high-resolution analyses of land-surface variables, such as surface canopy temperature, soil moisture, and snow conditions, to be used for the relaxation of lower boundary conditions in extended-range LAM simulations. The proposed method is based on performing offline simulations with an external surface model, forced with the near-surface meteorological fields derived from short-range forecast, operational analyses, and observed temperatures and humidity. Results show that the outputs of the surface model obtained in the present study have potential to improve the near-surface atmospheric fields in extended-range LAM integrations.
NASA Astrophysics Data System (ADS)
Shao, Yaping; Liu, Shaofeng; Schween, Jan H.; Crewell, Susanne
2013-08-01
A model is developed for the large-eddy simulation (LES) of heterogeneous atmosphere and land-surface processes. This couples a LES model with a land-surface scheme. New developments are made to the land-surface scheme to ensure the adequate representation of atmosphere-land-surface transfers on the large-eddy scale. These include, (1) a multi-layer canopy scheme; (2) a method for flux estimates consistent with the large-eddy subgrid closure; and (3) an appropriate soil-layer configuration. The model is then applied to a heterogeneous region with 60-m horizontal resolution and the results are compared with ground-based and airborne measurements. The simulated sensible and latent heat fluxes are found to agree well with the eddy-correlation measurements. Good agreement is also found in the modelled and observed net radiation, ground heat flux, soil temperature and moisture. Based on the model results, we study the patterns of the sensible and latent heat fluxes, how such patterns come into existence, and how large eddies propagate and destroy land-surface signals in the atmosphere. Near the surface, the flux and land-use patterns are found to be closely correlated. In the lower boundary layer, small eddies bearing land-surface signals organize and develop into larger eddies, which carry the signals to considerably higher levels. As a result, the instantaneous flux patterns appear to be unrelated to the land-use patterns, but on average, the correlation between them is significant and persistent up to about 650 m. For a given land-surface type, the scatter of the fluxes amounts to several hundred W { m }^{-2}, due to (1) large-eddy randomness; (2) rapid large-eddy and surface feedback; and (3) local advection related to surface heterogeneity.
Surface structural ion adsorption modeling of competitive binding of oxyanions by metal (hydr)oxides
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hiemstra, T.; Riemsdijk, W.H. van
1999-02-01
An important challenge in surface complexation models (SCM) is to connect the molecular microscopic reality to macroscopic adsorption phenomena. This study elucidates the primary factor controlling the adsorption process by analyzing the adsorption and competition of PO{sub 4}, AsO{sub 4}, and SeO{sub 3}. The authors show that the structure of the surface-complex acting in the dominant electrostatic field can be ascertained as the primary controlling adsorption factor. The surface species of arsenate are identical with those of phosphate and the adsorption behavior is very similar. On the basis of the selenite adsorption, The authors show that the commonly used 1pKmore » models are incapable to incorporate in the adsorption modeling the correct bidentate binding mechanism found by spectroscopy. The use of the bidentate mechanism leads to a proton-oxyanion ratio and corresponding pH dependence that are too large. The inappropriate intrinsic charge attribution to the primary surface groups and the condensation of the inner sphere surface complex to a point charge are responsible for this behavior of commonly used 2pK models. Both key factors are differently defined in the charge distributed multi-site complexation (CD-MUSIC) model and are based in this model on a surface structural approach. The CD-MUSIC model can successfully describe the macroscopic adsorption phenomena using the surface speciation and binding mechanisms as found by spectroscopy. The model is also able to predict the anion competition well. The charge distribution in the interface is in agreement with the observed structure of surface complexes.« less
Han, Jeong-Yeol; Kim, Sug-Whan; Han, Inwoo; Kim, Geon-Hee
2008-03-17
A new evolutionary grinding process model has been developed for nanometric control of material removal from an aspheric surface of Zerodur substrate. The model incorporates novel control features such as i) a growing database; ii) an evolving, multi-variable regression equation; and iii) an adaptive correction factor for target surface roughness (Ra) for the next machine run. This process model demonstrated a unique evolutionary controllability of machining performance resulting in the final grinding accuracy (i.e. averaged difference between target and measured surface roughness) of -0.2+/-2.3(sigma) nm Ra over seven trial machine runs for the target surface roughness ranging from 115 nm to 64 nm Ra.
Fractal modeling of fluidic leakage through metal sealing surfaces
NASA Astrophysics Data System (ADS)
Zhang, Qiang; Chen, Xiaoqian; Huang, Yiyong; Chen, Yong
2018-04-01
This paper investigates the fluidic leak rate through metal sealing surfaces by developing fractal models for the contact process and leakage process. An improved model is established to describe the seal-contact interface of two metal rough surface. The contact model divides the deformed regions by classifying the asperities of different characteristic lengths into the elastic, elastic-plastic and plastic regimes. Using the improved contact model, the leakage channel under the contact surface is mathematically modeled based on the fractal theory. The leakage model obtains the leak rate using the fluid transport theory in porous media, considering that the pores-forming percolation channels can be treated as a combination of filled tortuous capillaries. The effects of fractal structure, surface material and gasket size on the contact process and leakage process are analyzed through numerical simulations for sealed ring gaskets.
Surface tension driven flow in glass melts and model fluids
NASA Technical Reports Server (NTRS)
Mcneil, T. J.; Cole, R.; Subramanian, R. S.
1982-01-01
Surface tension driven flow has been investigated analytically and experimentally using an apparatus where a free column of molten glass or model fluids was supported at its top and bottom faces by solid surfaces. The glass used in the experiments was sodium diborate, and the model fluids were silicone oils. In both the model fluid and glass melt experiments, conclusive evidence was obtained to prove that the observed flow was driven primarily by surface tension forces. The experimental observations are in qualitative agreement with predictions from the theoretical model.
Heo, Tae Wook; Chen, Long-Qing; Wood, Brandon C.
2015-04-08
In this paper, we present a comprehensive phase-field model for simulating diffusion-mediated kinetic phase behaviors near the surface of a solid particle. The model incorporates elastic inhomogeneity and anisotropy, diffusion mobility anisotropy, interfacial energy anisotropy, and Cahn–Hilliard diffusion kinetics. The free energy density function is formulated based on the regular solution model taking into account the possible solute-surface interaction near the surface. The coherency strain energy is computed using the Fourier-spectral iterative-perturbation method due to the strong elastic inhomogeneity with a zero surface traction boundary condition. Employing a phase-separating Li XFePO 4 electrode particle for Li-ion batteries as a modelmore » system, we perform parametric three-dimensional computer simulations. The model permits the observation of surface phase behaviors that are different from the bulk counterpart. For instance, it reproduces the theoretically well-established surface modes of spinodal decomposition of an unstable solid solution: the surface mode of coherent spinodal decomposition and the surface-directed spinodal decomposition mode. We systematically investigate the influences of major factors on the kinetic surface phase behaviors during the diffusional process. Finally, our simulation study provides insights for tailoring the internal phase microstructure of a particle by controlling the surface phase morphology.« less
Modeling of hydrogen evolution reaction on the surface of GaInP2
NASA Astrophysics Data System (ADS)
Choi, Woon Ih; Wood, Brandon; Schwegler, Eric; Ogitsu, Tadashi
2012-02-01
GaInP2 is promising candidate material for hydrogen production using sunlight. It reduces solvated proton into hydrogen molecule using light-induced excited electrons in the photoelectrochemical cell. However, it is challenging to model hydrogen evolution reaction (HER) using first-principles molecular dynamics. Instead, we use Anderson-Newns model and generalized solvent coordinate in Marcus-Hush theory to describe adiabatic free energy surface of HER. Model parameters are fitted from the DFT calculations. We model Volmer-Heyrovsky reaction path on the surfaces of CuPt phase of GaInP2. We also discuss effects of surface oxide and catalyst atoms that exist on top of bare surfaces in experimental circumstances.
Application of surface complexation models to anion adsorption by natural materials.
Goldberg, Sabine
2014-10-01
Various chemical models of ion adsorption are presented and discussed. Chemical models, such as surface complexation models, provide a molecular description of anion adsorption reactions using an equilibrium approach. Two such models, the constant capacitance model and the triple layer model, are described in the present study. Characteristics common to all the surface complexation models are equilibrium constant expressions, mass and charge balances, and surface activity coefficient electrostatic potential terms. Methods for determining parameter values for surface site density, capacitances, and surface complexation constants also are discussed. Spectroscopic experimental methods of establishing ion adsorption mechanisms include vibrational spectroscopy, nuclear magnetic resonance spectroscopy, electron spin resonance spectroscopy, X-ray absorption spectroscopy, and X-ray reflectivity. Experimental determinations of point of zero charge shifts and ionic strength dependence of adsorption results and molecular modeling calculations also can be used to deduce adsorption mechanisms. Applications of the surface complexation models to heterogeneous natural materials, such as soils, using the component additivity and the generalized composite approaches are described. Emphasis is on the generalized composite approach for predicting anion adsorption by soils. Continuing research is needed to develop consistent and realistic protocols for describing ion adsorption reactions on soil minerals and soils. The availability of standardized model parameter databases for use in chemical speciation-transport models is critical. Published 2014 Wiley Periodicals Inc. on behalf of SETAC. This article is a US Government work and as such, is in the public domain in the in the United States of America.
Particle-Surface Interaction Model and Method of Determining Particle-Surface Interactions
NASA Technical Reports Server (NTRS)
Hughes, David W. (Inventor)
2012-01-01
A method and model of predicting particle-surface interactions with a surface, such as the surface of a spacecraft. The method includes the steps of: determining a trajectory path of a plurality of moving particles; predicting whether any of the moving particles will intersect a surface; predicting whether any of the particles will be captured by the surface and/or; predicting a reflected trajectory and velocity of particles reflected from the surface.
NASA Astrophysics Data System (ADS)
Ngodock, H.; Carrier, M.; Smith, S. R.; Souopgui, I.; Martin, P.; Jacobs, G. A.
2016-02-01
The representer method is adopted for solving a weak constraints 4dvar problem for the assimilation of ocean observations including along-track SSH, using a free surface ocean model. Direct 4dvar assimilation of SSH observations along the satellite tracks requires that the adjoint model be integrated with Dirac impulses on the right hand side of the adjoint equations for the surface elevation equation. The solution of this adjoint model will inevitably include surface gravity waves, and it constitutes the forcing for the tangent linear model (TLM) according to the representer method. This yields an analysis that is contaminated by gravity waves. A method for avoiding the generation of the surface gravity waves in the analysis is proposed in this study; it consists of removing the adjoint of the free surface from the right hand side (rhs) of the free surface mode in the TLM. The information from the SSH observations will still propagate to all other variables via the adjoint of the balance relationship between the barotropic and baroclinic modes, resulting in the correction to the surface elevation. Two assimilation experiments are carried out in the Gulf of Mexico: one with adjoint forcing included on the rhs of the TLM free surface equation, and the other without. Both analyses are evaluated against the assimilated SSH observations, SSH maps from Aviso and independent surface drifters, showing that the analysis that did not include adjoint forcing in the free surface is more accurate. This study shows that when a weak constraint 4dvar approach is considered for the assimilation of along-track SSH observations using a free surface model, with the aim of correcting the mesoscale circulation, an independent model error should not be assigned to the free surface.
NASA Astrophysics Data System (ADS)
Triantafyllou, A. G.; Kalogiros, J.; Krestou, A.; Leivaditou, E.; Zoumakis, N.; Bouris, D.; Garas, S.; Konstantinidis, E.; Wang, Q.
2018-03-01
This paper provides the performance evaluation of the meteorological component of The Air Pollution Model (TAPM), a nestable prognostic model, in predicting meteorological variables in urban areas, for both its surface layer and atmospheric boundary layer (ABL) turbulence parameterizations. The model was modified by incorporating four urban land surface types, replacing the existing single urban surface. Control runs were carried out over the wider area of Kozani, an urban area in NW Greece. The model was evaluated for both surface and ABL meteorological variables by using measurements of near-surface and vertical profiles of wind and temperature. The data were collected by using monitoring surface stations in selected sites as well as an acoustic sounder (SOnic Detection And Ranging (SODAR), up to 300 m above ground) and a radiometer profiler (up to 600 m above ground). The results showed the model demonstrated good performance in predicting the near-surface meteorology in the Kozani region for both a winter and a summer month. In the ABL, the comparison showed that the model's forecasts generally performed well with respect to the thermal structure (temperature profiles and ABL height) but overestimated wind speed at the heights of comparison (mostly below 200 m) up to 3-4 ms-1.
Painter, Scott L.; Coon, Ethan T.; Atchley, Adam L.; ...
2016-08-11
The need to understand potential climate impacts and feedbacks in Arctic regions has prompted recent interest in modeling of permafrost dynamics in a warming climate. A new fine-scale integrated surface/subsurface thermal hydrology modeling capability is described and demonstrated in proof-of-concept simulations. The new modeling capability combines a surface energy balance model with recently developed three-dimensional subsurface thermal hydrology models and new models for nonisothermal surface water flows and snow distribution in the microtopography. Surface water flows are modeled using the diffusion wave equation extended to include energy transport and phase change of ponded water. Variation of snow depth in themore » microtopography, physically the result of wind scour, is also modeled heuristically with a diffusion wave equation. The multiple surface and subsurface processes are implemented by leveraging highly parallel community software. Fully integrated thermal hydrology simulations on the tilted open book catchment, an important test case for integrated surface/subsurface flow modeling, are presented. Fine-scale 100-year projections of the integrated permafrost thermal hydrological system on an ice wedge polygon at Barrow Alaska in a warming climate are also presented. Finally, these simulations demonstrate the feasibility of microtopography-resolving, process-rich simulations as a tool to help understand possible future evolution of the carbon-rich Arctic tundra in a warming climate.« less
NASA Astrophysics Data System (ADS)
Melchior van Wessem, Jan; van de Berg, Willem Jan; Noël, Brice P. Y.; van Meijgaard, Erik; Amory, Charles; Birnbaum, Gerit; Jakobs, Constantijn L.; Krüger, Konstantin; Lenaerts, Jan T. M.; Lhermitte, Stef; Ligtenberg, Stefan R. M.; Medley, Brooke; Reijmer, Carleen H.; van Tricht, Kristof; Trusel, Luke D.; van Ulft, Lambertus H.; Wouters, Bert; Wuite, Jan; van den Broeke, Michiel R.
2018-04-01
We evaluate modelled Antarctic ice sheet (AIS) near-surface climate, surface mass balance (SMB) and surface energy balance (SEB) from the updated polar version of the regional atmospheric climate model, RACMO2 (1979-2016). The updated model, referred to as RACMO2.3p2, incorporates upper-air relaxation, a revised topography, tuned parameters in the cloud scheme to generate more precipitation towards the AIS interior and modified snow properties reducing drifting snow sublimation and increasing surface snowmelt. Comparisons of RACMO2 model output with several independent observational data show that the existing biases in AIS temperature, radiative fluxes and SMB components are further reduced with respect to the previous model version. The model-integrated annual average SMB for the ice sheet including ice shelves (minus the Antarctic Peninsula, AP) now amounts to 2229 Gt y-1, with an interannual variability of 109 Gt y-1. The largest improvement is found in modelled surface snowmelt, which now compares well with satellite and weather station observations. For the high-resolution ( ˜ 5.5 km) AP simulation, results remain comparable to earlier studies. The updated model provides a new, high-resolution data set of the contemporary near-surface climate and SMB of the AIS; this model version will be used for future climate scenario projections in a forthcoming study.
The monocular visual imaging technology model applied in the airport surface surveillance
NASA Astrophysics Data System (ADS)
Qin, Zhe; Wang, Jian; Huang, Chao
2013-08-01
At present, the civil aviation airports use the surface surveillance radar monitoring and positioning systems to monitor the aircrafts, vehicles and the other moving objects. Surface surveillance radars can cover most of the airport scenes, but because of the terminals, covered bridges and other buildings geometry, surface surveillance radar systems inevitably have some small segment blind spots. This paper presents a monocular vision imaging technology model for airport surface surveillance, achieving the perception of scenes of moving objects such as aircrafts, vehicles and personnel location. This new model provides an important complement for airport surface surveillance, which is different from the traditional surface surveillance radar techniques. Such technique not only provides clear objects activities screen for the ATC, but also provides image recognition and positioning of moving targets in this area. Thereby it can improve the work efficiency of the airport operations and avoid the conflict between the aircrafts and vehicles. This paper first introduces the monocular visual imaging technology model applied in the airport surface surveillance and then the monocular vision measurement accuracy analysis of the model. The monocular visual imaging technology model is simple, low cost, and highly efficient. It is an advanced monitoring technique which can make up blind spot area of the surface surveillance radar monitoring and positioning systems.
Hartvig, Rune A; van de Weert, Marco; Østergaard, Jesper; Jorgensen, Lene; Jensen, Henrik
2011-03-15
The understanding of protein adsorption at charged surfaces is important for a wide range of scientific disciplines including surface engineering, separation sciences and pharmaceutical sciences. Compared to chemical entities having a permanent charge, the adsorption of small ampholytes and proteins is more complicated as the pH near a charged surface can be significantly different from the value in bulk solution. In this work, we have developed a phenomenological adsorption model which takes into account the combined role of interfacial ion distribution, interfacial charge regulation of amino acids in the proximity of the surface, electroneutrality, and mass balance. The model is straightforward to apply to a given set of experimental conditions as most model parameters are obtained from bulk properties and therefore easy to estimate or are directly measurable. The model provides a detailed understanding of the importance of surface charge on adsorption and in particular of how changes in surface charge, concentration, and surface area may affect adsorption behavior. The model is successfully used to explain the experimental adsorption behavior of the two model proteins lysozyme and α-lactalbumin. It is demonstrated that it is possible to predict the pH and surface charge dependent adsorption behavior from experimental or theoretical estimates of a preferred orientation of a protein at a solid charged interface.
Measuring Geophysical Parameters of the Greenland Ice Sheet using Airborne Radar Altimetry
NASA Technical Reports Server (NTRS)
Ferraro, Ellen J.; Swift. Calvin T.
1995-01-01
This paper presents radar-altimeter scattering models for each of the diagenetic zones of the Greenland ice sheet. AAFE radar- altimeter waveforms obtained during the 1991 and 1993 NASA multi-sensor airborne altimetry experiments over Greenland reveal that the Ku-band return pulse changes significantly with the different diagenetic zones. These changes are due to varying amounts of surface and volume scattering in the return waveform. In the ablation and soaked zones, where surface scattering dominates the AAFE return, geophysical parameters such as rms surface height and rms surface slope are obtained by fitting the waveforms to a surface-scattering model. Waveforms from the percolation zone show that the sub-surface ice features have a much more significant effect on the return pulse than the surrounding snowpack. Model percolation waveforms, created using a combined surface- and volume-scattering model and an ice-feature distribution obtained during the 1993 field season, agree well with actual AAFE waveforms taken in the same time period. Using a combined surface- and volume-scattering model for the dry-snow-zone return waveforms, the rms surface height and slope and the attenuation coefficient of the snowpack are obtained. These scattering models not only allow geophysical parameters of the ice sheet to be measured but also help in the understanding of satellite radar-altimeter data.
Bayesian Hierarchical Model Characterization of Model Error in Ocean Data Assimilation and Forecasts
2013-09-30
wind ensemble with the increments in the surface momentum flux control vector in a four-dimensional variational (4dvar) assimilation system. The...stability effects? surface stress Surface Momentum Flux Ensembles from Summaries of BHM Winds (Mediterranean...surface wind speed given ensemble winds from a Bayesian Hierarchical Model to provide surface momentum flux ensembles. 3 Figure 2: Domain of
NASA Astrophysics Data System (ADS)
Wetzel, Peter J.; Boone, Aaron
1995-07-01
This paper presents a general description of, and demonstrates the capabilities of, the Parameterization for Land-Atmosphere-Cloud Exchange (PLACE). The PLACE model is a detailed process model of the partly cloudy atmospheric boundary layer and underlying heterogeneous land surfaces. In its development, particular attention has been given to three of the model's subprocesses: the prediction of boundary layer cloud amount, the treatment of surface and soil subgrid heterogeneity, and the liquid water budget. The model includes a three-parameter nonprecipitating cumulus model that feeds back to the surface and boundary layer through radiative effects. Surface heterogeneity in the PLACE model is treated both statistically and by resolving explicit subgrid patches. The model maintains a vertical column of liquid water that is divided into seven reservoirs, from the surface interception store down to bedrock.Five single-day demonstration cases are presented, in which the PLACE model was initialized, run, and compared to field observations from four diverse sites. The model is shown to predict cloud amount well in these while predicting the surface fluxes with similar accuracy. A slight tendency to underpredict boundary layer depth is noted in all cases.Sensitivity tests were also run using anemometer-level forcing provided by the Project for Inter-comparison of Land-surface Parameterization Schemes (PILPS). The purpose is to demonstrate the relative impact of heterogeneity of surface parameters on the predicted annual mean surface fluxes. Significant sensitivity to subgrid variability of certain parameters is demonstrated, particularly to parameters related to soil moisture. A major result is that the PLACE-computed impact of total (homogeneous) deforestation of a rain forest is comparable in magnitude to the effect of imposing heterogeneity of certain surface variables, and is similarly comparable to the overall variance among the other PILPS participant models. Were this result to be bourne out by further analysis, it would suggest that today's average land surface parameterization has little credibility when applied to discriminating the local impacts of any plausible future climate change.
Seemann, M D; Gebicke, K; Luboldt, W; Albes, J M; Vollmar, J; Schäfer, J F; Beinert, T; Englmeier, K H; Bitzer, M; Claussen, C D
2001-07-01
The aim of this study was to demonstrate the possibilities of a hybrid rendering method, the combination of a color-coded surface and volume rendering method, with the feasibility of performing surface-based virtual endoscopy with different representation models in the operative and interventional therapy control of the chest. In 6 consecutive patients with partial lung resection (n = 2) and lung transplantation (n = 4) a thin-section spiral computed tomography of the chest was performed. The tracheobronchial system and the introduced metallic stents were visualized using a color-coded surface rendering method. The remaining thoracic structures were visualized using a volume rendering method. For virtual bronchoscopy, the tracheobronchial system was visualized using a triangle surface model, a shaded-surface model and a transparent shaded-surface model. The hybrid 3D visualization uses the advantages of both the color-coded surface and volume rendering methods and facilitates a clear representation of the tracheobronchial system and the complex topographical relationship of morphological and pathological changes without loss of diagnostic information. Performing virtual bronchoscopy with the transparent shaded-surface model facilitates a reasonable to optimal, simultaneous visualization and assessment of the surface structure of the tracheobronchial system and the surrounding mediastinal structures and lesions. Hybrid rendering relieve the morphological assessment of anatomical and pathological changes without the need for time-consuming detailed analysis and presentation of source images. Performing virtual bronchoscopy with a transparent shaded-surface model offers a promising alternative to flexible fiberoptic bronchoscopy.
Psychophysically based model of surface gloss perception
NASA Astrophysics Data System (ADS)
Ferwerda, James A.; Pellacini, Fabio; Greenberg, Donald P.
2001-06-01
In this paper we introduce a new model of surface appearance that is based on quantitative studies of gloss perception. We use image synthesis techniques to conduct experiments that explore the relationships between the physical dimensions of glossy reflectance and the perceptual dimensions of glossy appearance. The product of these experiments is a psychophysically-based model of surface gloss, with dimensions that are both physically and perceptually meaningful and scales that reflect our sensitivity to gloss variations. We demonstrate that the model can be used to describe and control the appearance of glossy surfaces in synthesis images, allowing prediction of gloss matches and quantification of gloss differences. This work represents some initial steps toward developing psychophyscial models of the goniometric aspects of surface appearance to complement widely-used colorimetric models.
Yi, S.; Li, N.; Xiang, B.; Wang, X.; Ye, B.; McGuire, A.D.
2013-01-01
Soil surface temperature is a critical boundary condition for the simulation of soil temperature by environmental models. It is influenced by atmospheric and soil conditions and by vegetation cover. In sophisticated land surface models, it is simulated iteratively by solving surface energy budget equations. In ecosystem, permafrost, and hydrology models, the consideration of soil surface temperature is generally simple. In this study, we developed a methodology for representing the effects of vegetation cover and atmospheric factors on the estimation of soil surface temperature for alpine grassland ecosystems on the Qinghai-Tibetan Plateau. Our approach integrated measurements from meteorological stations with simulations from a sophisticated land surface model to develop an equation set for estimating soil surface temperature. After implementing this equation set into an ecosystem model and evaluating the performance of the ecosystem model in simulating soil temperature at different depths in the soil profile, we applied the model to simulate interactions among vegetation cover, freeze-thaw cycles, and soil erosion to demonstrate potential applications made possible through the implementation of the methodology developed in this study. Results showed that (1) to properly estimate daily soil surface temperature, algorithms should use air temperature, downward solar radiation, and vegetation cover as independent variables; (2) the equation set developed in this study performed better than soil surface temperature algorithms used in other models; and (3) the ecosystem model performed well in simulating soil temperature throughout the soil profile using the equation set developed in this study. Our application of the model indicates that the representation in ecosystem models of the effects of vegetation cover on the simulation of soil thermal dynamics has the potential to substantially improve our understanding of the vulnerability of alpine grassland ecosystems to changes in climate and grazing regimes.
NASA Astrophysics Data System (ADS)
Yi, S.; Li, N.; Xiang, B.; Wang, X.; Ye, B.; McGuire, A. D.
2013-07-01
surface temperature is a critical boundary condition for the simulation of soil temperature by environmental models. It is influenced by atmospheric and soil conditions and by vegetation cover. In sophisticated land surface models, it is simulated iteratively by solving surface energy budget equations. In ecosystem, permafrost, and hydrology models, the consideration of soil surface temperature is generally simple. In this study, we developed a methodology for representing the effects of vegetation cover and atmospheric factors on the estimation of soil surface temperature for alpine grassland ecosystems on the Qinghai-Tibetan Plateau. Our approach integrated measurements from meteorological stations with simulations from a sophisticated land surface model to develop an equation set for estimating soil surface temperature. After implementing this equation set into an ecosystem model and evaluating the performance of the ecosystem model in simulating soil temperature at different depths in the soil profile, we applied the model to simulate interactions among vegetation cover, freeze-thaw cycles, and soil erosion to demonstrate potential applications made possible through the implementation of the methodology developed in this study. Results showed that (1) to properly estimate daily soil surface temperature, algorithms should use air temperature, downward solar radiation, and vegetation cover as independent variables; (2) the equation set developed in this study performed better than soil surface temperature algorithms used in other models; and (3) the ecosystem model performed well in simulating soil temperature throughout the soil profile using the equation set developed in this study. Our application of the model indicates that the representation in ecosystem models of the effects of vegetation cover on the simulation of soil thermal dynamics has the potential to substantially improve our understanding of the vulnerability of alpine grassland ecosystems to changes in climate and grazing regimes.
CO adsorption on the “29” Cu xO/Cu(111) surface: An integrated DFT, STM, and TPD study
Hensley, Alyssa J. R.; Therrien, Andrew J.; Zhang, Renqin; ...
2016-10-04
The elucidation of an accurate atomistic model of surface structures is crucial for the design and understanding of effective catalysts, a process requiring a close collaboration between experimental observations and theoretical models. Any developed surface theoretical model must agree with experimental results for the surface when both clean and adsorbate covered. Here, we present a detailed study of the adsorption of CO on the “29” Cu xO/ Cu(111) surface, which is important in the understanding of ubiquitous Cubased catalysis. This study uses scanning tunneling microscopy, temperatureprogrammed desorption, and density functional theory to analyze CO adsorption on the “29” Cu xO/Cu(111)more » surface. From the experimental scanning tunneling microscopy images, CO was found to form six different ordered structures on the “29” Cu xO/Cu(111) surface depending on the surface CO coverage. By modeling the adsorption of CO on our atomistic model of the “29” Cu xO/Cu(111) surface at different coverages, we were able to match the experimentally observed CO ordered structures to specific combinations of sites on the “29” Cu xO/Cu(111) surface. Lastly, the high degree of agreement seen here between experiment and theory for the adsorption of CO on the “29” Cu xO/Cu(111) surface at various CO coverages provides further support that our atomistic model of the “29” Cu xO/Cu(111) surface is experimentally accurate.« less
Effects of orientation and downward-facing convex curvature on pool-boiling critical heat flux
NASA Astrophysics Data System (ADS)
Howard, Alicia Ann Harris
Photographic studies of near-saturated pool boiling on both inclined flat surfaces and a downward-facing convex surface were conducted in order to determine the physical mechanisms that trigger critical heat flux (CHF). Based on the vapor behavior observed just prior to CHF, it is shown for the flat surfaces that the surface orientations can be divided into three regions: upward-facing (0-60°), near-vertical (60-165°), and downward-facing (165-180°) each region is associated with a unique CHIP trigger mechanism. In the upward-facing region, the buoyancy forces remove the vapor vertically off the heater surface. The near- vertical region is characterized by a wavy liquid-vapor interface which sweeps along the heater surface. In the downward-facing region, the vapor repeatedly stratifies on the heater surface, greatly decreasing CHF. The vapor behavior along the convex surface is cyclic in nature and similar to the nucleation/coalescence/stratification/release procedure observed for flat surfaces in the downward-facing region. The vapor stratification occurred at the bottom (downward-facing) heaters on the convex surface. CHF is always triggered on these downward-facing heaters and then propagates up the convex surface, and the orientations of these heaters are comparable with the orientation range of the flat surface downward-facing region. The vast differences between the observed vapor behavior within the three regions and on the convex surface indicate that a single overall pool boiling CHF model cannot possibly account for all the observed effects. Upward-facing surfaces have been examined and modeled extensively by many investigators and a few investigators have addressed downward-facing surfaces, so this investigation focuses on modeling the near-vertical region. The near-vertical CHF model incorporates classical two-dimensional interfacial instability theory, a separated flow model, an energy balance, and a criterion for separation of the wavy interface from the surface at CHF. The model was tested for different fluids and shows good agreement with CHF data. Additionally, the instability theory incorporated into this model accurately predicts the angle of transition between the near-vertical and downward-facing regions.
Surface energy fluxes and their representation in CMIP5 models
NASA Astrophysics Data System (ADS)
Wild, M.
2016-12-01
Energy fluxes at the Earth surface play a key role in the determination of surface climate and in the coupling of atmosphere, land and ocean components. Unlike their counterparts at the top of atmosphere (TOA), surface fluxes cannot be directly measured from satellites, but have to be inferred from the space-born observations using additional models to account for atmospheric perturbations, or from the limited number of surface observations. Uncertainties in the energy fluxes at the surface have therefore traditionally been larger than at the TOA, and have limited our knowledge on the distribution of the energy flows within the climate system. Accordingly, current climate models still largely differ in their representation of surface and atmospheric energy fluxes. Since the mid-1990s, accurate flux measurements became increasingly available from surface networks such as BSRN, which allow to better constrain the surface energy fluxes. There is, however, still a lack of flux measurements particularly over oceans. Further, the larger-scale representativeness of the station records needs to be assessed to judge their suitability as anchor sites for gridded flux products inferred from satellites, reanalyses and climate models. In addition, historic records need to be carefully quality-checked and homogeneized. In parallel, satellite-derived products of surface fluxes profit from the great advancement in space-born observations since the turn of the millennium, and from improved validation capabilities with surface observations. Ultimately, it is the combination of surface and space-born observations, reanalyses and modeling approaches that will advance our knowledge on the distribution of the surface energy fluxes. Uncertainties remain in the determination of surface albedo, skin temperatures and the partitioning of surface net radiation into the sensible and latent heat. Climate models over generations up to present day (CMIP5) tend to overestimate the downward shortwave and underestimate the downward longwave radiation. A challenge also remains the consistent representation of the global energy and water cycles. Yet it is shown that those climate models with a realistic surface radiation balance also simulate global precipitation amounts within the uncertainty range of observational estimates.
A Catchment-Based Approach to Modeling Land Surface Processes in a GCM. Part 1; Model Structure
NASA Technical Reports Server (NTRS)
Koster, Randal D.; Suarez, Max J.; Ducharne, Agnes; Stieglitz, Marc; Kumar, Praveen
2000-01-01
A new strategy for modeling the land surface component of the climate system is described. The strategy is motivated by an arguable deficiency in most state-of-the-art land surface models (LSMs), namely the disproportionately higher emphasis given to the formulation of one-dimensional, vertical physics relative to the treatment of horizontal heterogeneity in surface properties -- particularly subgrid soil moisture variability and its effects on runoff generation. The new strategy calls for the partitioning of the continental surface into a mosaic of hydrologic catchments, delineated through analysis of high-resolution surface elevation data. The effective "grid" used for the land surface is therefore not specified by the overlying atmospheric grid. Within each catchment, the variability of soil moisture is related to characteristics of the topography and to three bulk soil moisture variables through a well-established model of catchment processes. This modeled variability allows the partitioning of the catchment into several areas representing distinct hydrological regimes, wherein distinct (regime-specific) evaporation and runoff parameterizations are applied. Care is taken to ensure that the deficiencies of the catchment model in regions of little to moderate topography are minimized.
The Value of GRACE Data in Improving, Assessing and Evaluating Land Surface and Climate Models
NASA Astrophysics Data System (ADS)
Yang, Z.
2011-12-01
I will review how the Gravity Recovery and Climate Experiment (GRACE) satellite measurements have improved land surface models that are developed for weather, climate, and hydrological studies. GRACE-derived terrestrial water storage (TWS) changes have been successfully used to assess and evaluate the improved representations of land-surface hydrological processes such as groundwater-soil moisture interaction, frozen soil and infiltration, and the topographic control on runoff production, as evident in the simulations from the latest Noah-MP, the Community Land Model, and the Community Climate System Model. GRACE data sets have made it possible to estimate key terrestrial water storage components (snow mass, surface water, groundwater or water table depth), biomass, and surface water fluxes (evapotranspiration, solid precipitation, melt of snow/ice). Many of the examples will draw from my Land, Environment and Atmosphere Dynamics group's work on land surface model developments, snow mass retrieval, and multi-sensor snow data assimilation using the ensemble Karman filter and the ensemble Karman smoother. Finally, I will briefly outline some future directions in using GRACE in land surface modeling.
Specification for a surface-search radar-detection-range model
NASA Astrophysics Data System (ADS)
Hattan, Claude P.
1990-09-01
A model that predicts surface-search radar detection range versus a variety of combatants has been developed at the Naval Ocean Systems Center. This model uses a simplified ship radar cross section (RCS) model and the U.S. Navy Oceanographic and Atmospheric Mission Library Standard Electromagnetic Propagation Model. It provides the user with a method of assessing the effects of the environment of the performance of a surface-search radar system. The software implementation of the model is written in ANSI FORTRAN 77, with MIL-STD-1753 extensions. The program provides the user with a table of expected detection ranges when the model is supplied with the proper environmental radar system inputs. The target model includes the variation in RCS as a function of aspect angle and the distribution of reflected radar energy as a function of height above the waterline. The modeled propagation effects include refraction caused by a multisegmented refractivity profile, sea-surface roughness caused by local winds, evaporation ducting, and surface-based ducts caused by atmospheric layering.