WorldWideScience

Sample records for geosphere transport parameters

  1. Workshop on spent fuel performance, radionuclide chemistry and geosphere transport parameters, Lidingoe 2008: Overview and evaluation of recent SKB procedures

    Energy Technology Data Exchange (ETDEWEB)

    Meinrath, Guenther; Stenhouse, Mike; Brown, Paul; Ekberg, Christian; Jegou, Christophe; Nitsche, Heino

    2009-08-15

    The safety assessment for disposal of spent nuclear fuel canister in the Swedish bedrock should thoroughly address the time period after a containment failure. Such a failure could be expected as a result of corrosion damage or mechanical failure due to rock movement. This report mainly covers some issues connected to parameters used for radionuclide transport calculations in the areas of spent fuel performance (for fuel in contact with groundwater), radionuclide chemistry, and sorption and geosphere transport parameters. Some examples of topics that are elaborated in some detail include statistical treatment of measurement data (for sorption measurements), handling of uncertainties in speciation calculations, use of triangular distributions in safety assessment and physical processes in connection with spent fuel aging. The results emerged from discussions among international experts at a workshop in May 2008. The purpose of this work is providing an overview of ongoing work within the Swedish Nuclear Fuel and Waste Management Co. (SKB), to provide ideas and suggestions for methodology development and to develop review capability within the SSM. The authors conclude that SKB's treatment of uncertainty in speciation calculations has improved, but that additional efforts in the area of error propagation are recommended. In efforts to condense the scope of utilised thermodynamic databases, the authors recommend that exclusion criteria should be explicitly stated. In the area of sorption, there is a need for more thorough analysis of errors in order to establish uncertainty ranges. The most essential improvements concern dose-limiting nuclides (e.g. Ra-226). Triangular distributions are often featured in SKB safety assessment, but it is not clear that the use of such distributions is based on a firm understanding of its properties. Regarding fuel performance, while safety assessment parameters are supported by measurement data there is still a need for better

  2. Geosphere transport of radionuclides in safety assessment of spent fuel disposal

    Energy Technology Data Exchange (ETDEWEB)

    Jussila, P

    2000-07-01

    The study is associated with a research project of Radiation and Nuclear Safety Authority (STUK) to utilise analytical models in safety assessment for disposal of spent nuclear fuel. Geosphere constitutes a natural barrier for the possible escape of radionuclides from a geological repository of spent nuclear fuel. However, rock contains fractures in which flowing groundwater can transport material. Radionuclide transport in rock is complicated - the flow paths in the geosphere are difficult to characterise and there are various phenomena involved. In mathematical models, critical paths along which radionuclides can reach the biosphere are considered. The worst predictable cases and the effect of the essential parameters can be assessed with the help of such models although they simplify the reality considerably. Some of the main differences between the transport model used and the reality are the mathematical characterisation of the flow route in rock as a smooth and straight fracture and the modelling of the complicated chemical processes causing retardation with the help of a distribution coefficient that does not explain those phenomena. Radionuclide transport models via a heat transfer analogy and analytical solutions of them are derived in the study. The calculations are performed with a created Matlab program for a single nuclide model taking into account 1D advective transport along a fracture, 1D diffusion from the fracture into and within the porous rock matrices surrounding the fracture, retardation within the matrices, and radioactive decay. The results are compared to the results of the same calculation cases obtained by Technical Research Centre of Finland (VTT) and presented in TILA-99 safety assessment report. The model used by VTT is the same but the results have been calculated numerically in different geometry. The differences between the results of the present study and TILA-99 can to a large extent be explained by the different approaches to

  3. Bedrock K{sub d} data and uncertainty assessment for application in SR-Site geosphere transport calculations

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, James (Kemakta Konsult AB, Stockholm (Sweden))

    2010-12-15

    The safety assessment SR-Site is undertaken to assess the safety of a potential geologic repository for spent nuclear fuel at the Forsmark and Laxemar sites. The present report is one of several reports that form the data input to SR-Site and contains a compilation of recommended K{sub d} data (i.e. linear partitioning coefficients) for safety assessment modelling of geosphere radionuclide transport. The data are derived for rock types and groundwater compositions distinctive of the site investigation areas at Forsmark and Laxemar. Data have been derived for all elements and redox states considered of importance for far-field dose estimates as described in /SKB 2010d/. The K{sub d} data are given in the form of lognormal distributions characterised by a mean (mu) and standard deviation (sigma). Upper and lower limits for the uncertainty range of the recommended data are defined by the 2.5% and 97.5% percentiles of the empirical data sets. The best estimate K{sub d} value for use in deterministic calculations is given as the median of the K{sub d} distribution

  4. Review of SR-Can: Evaluation of SKB's handling of spent fuel performance, radionuclide chemistry and geosphere transport parameters. External review contribution in support of SKI's and SSI's review of SR-Can

    Energy Technology Data Exchange (ETDEWEB)

    Stenhouse, Mike (Monitor Scientific LLC, Denver, CO (US)); Jegou, Christophe (Commissariat a l' Energie Atomique (CEA) (FR)); Brown, Paul (Geochem Australia (AU)); Meinrath, Guenther (RER Consultants, Passau (DE)); Nitsche, Heino (Univ. of California, Berkeley (US)); Ekberg, Christian (Chalmers University of Technology (SE))

    2008-03-15

    SR-Can covers the containment phase of the KBS-3 barriers as well as the consequences of releases of radionuclides to the rock and eventually the biosphere (after complete containment within fuel canisters has partially failed). The aim of this report is to provide a range of review comments with respect to those parameters related to spent fuel performance as well as radionuclide chemistry and transport. These parameter values are used in the quantification of consequences due to release of radionuclides from potentially leaking canisters. The report does not cover modelling approaches used for quantification of consequences. However, modelling used to derive parameter values is to some extent addressed (such as calculation of maximum radionuclide concentration due to formation of solubility limiting phases). The following are the key highlights and comments generated in the course of the review: Inconsistencies exist between recommendations provided in technical reports and those quoted in the Data Report. One of the reasons for such inconsistencies has been the timing of different pieces of research. It is hoped that the timing of contributions to SR-Site will be such that these inconsistencies can be avoided. Sensitivity analyses need to be carried out and reported in a number of areas to support some of the assumptions or decisions made in the assessment calculations. The likelihood is that SKB has performed many of the sensitivity analyses identified in different parts of this report, but these need to be reported, preferably to complement the recommendations provided

  5. On the numerical simulation of uncertain parameters in a radionuclide transport model; Modelisation numerique de parametres incertains associes a un modele de transport de radionucleides

    Energy Technology Data Exchange (ETDEWEB)

    Diaz Moreno, J.M.; Ortegon Gallego, F. [Universidad de Cadiz, Dept. de Matematicas, CASEM (Spain); Lazaar, S. [Universite AbdelMalek Essaadi, Ecole Nationale des Sciences Appliquees, Dept. de Mathematiques et Informatique, Tanger Principale (Morocco)

    2007-10-15

    We study a fast algorithm to generate random fields which represent the uncertain parameters in a transport model of radionuclides in the geosphere. This algorithm has been introduced by Mikhailov and is based on a procedure known as Palm process. It can then be applied in a Monte Carlo method in the probabilistic risk assessment of high-level radioactive waste disposal in deep formation. We use this algorithm in order to compute the retardation factor appearing in the radionuclide migration model and we compare the CPU time corresponding to this procedure versus a classical spectral method. (authors)

  6. From the Geosphere to the Cosmos

    CERN Multimedia

    2010-01-01

    On 1 -2 December, the European Network ASPERA will be organising the “From the Geosphere to the Cosmos” workshop at the Palais de la Découverte in Paris. The LIDO platform, 3D-radiography projects for volcanoes, and CERN’s CLOUD experiment are among the interdisciplinary projects that will be presented at the workshop.   Astroparticle physics is a new field mixing both particle physics and astrophysics. It offers many new opportunities for environmental disciplines such as oceanography, climate science and studies of the atmosphere, and geology. “From the Geosphere to the Cosmos” workshop will present them to the scientific community and the press. LIDO: Probing new territories Whales sing at the same wavelength as the neutrinos emitted by stars. This happy coincidence gave physicists the idea to share their undersea telescopes with marine biologists. By helping the development of a bioacoustics network to monitor the deep-sea envir...

  7. Transformation Pathways through the Land-water Geosphere in Permafrost Regions

    Science.gov (United States)

    Destouni, G.

    2014-12-01

    Arctic land-water undergoes and participates in multiple climate-driven and other (natural and direct human-driven) environmental exchanges and changes (Figure 1). A bits-and-pieces approach to these may miss essential aspects of change propagation and transformation by land-water across its multiple components (soil water, groundwater, hyporheic water, streams/rivers, wetlands and lakes) and from/to other geospheres (atmosphere and its climate change drivers, cryosphere and its permafrost segment, as well as the anthroposphere/technosphere, geosphere/pedosphere, marine hydrosphere and biosphere). This paper synthesizes results from recent modeling and observational studies of land-water flow and dissolved carbon transport in permafrost regions, departing from a new conceptualization of the land-water geosphere as a scale-free catchment-wise organized system (Figure 1), emphasizing several key new system aspects compared to traditional hydrosphere/water cycle view. Among these new aspects, we particularly investigate here the role of land-water flow and transport pathways as system coupling agents, with focus on their variability and change with varying permafrost conditions and permafrost thaw in a warming climate. Utilizing the conceptualization of land-water as a continuous yet structured geosphere, following the proposed flow-transport pathways of change propagation-transformation, we identify patterns of permafrost-related and other changes in Arctic hydrology.

  8. Numerical model to simulate the isotopic and heat release and transport through the geosphere from a geological repository of radioactive wastes; Un modelo numerico para la simulacion de transporte de calor y liberacion de materia en un almacenamiento profundo de residuos radiactivos

    Energy Technology Data Exchange (ETDEWEB)

    Hidalgo Lopez, A. [Universidad Politecnica de Madrid (Spain)

    2002-07-01

    The aim of this research is to simulate the isotopic and heat release and transport through the geosphere, from a geological repository of high level nuclear waste. in order to achieve it, different physical processes, that have to do with the problem, are considered: groundwater flow, radioactive decay, nuclide dissolution in groundwater, heat generation, mass and heat transport. Some of these phenomena are related among the, which allows to build a coupled model,which is the starting point to generate a FORTRAN code. The flow and transport models are developed in two spatial dimensions and are integrated in space by means of a finite volume method. The time integration is fulfilled by a {theta}-method. Moreover, the advection-diffusion equation is solved by two finite volume techniques. In the first one a linear interpolation is used whereas in the second it is used a quadratic one. Also, a consistency an stability study of both methods is carried out in order to compare their stability zones and the errors appearing. Stability is analysed by applying the von Neumann method, which is based upon Fourier series. Although it is a classical technique when dealing with finite-difference schemes, it is here applied to two finite volume schemes. (Author)

  9. Minimum QOS Parameter Set in Transport Layer

    Institute of Scientific and Technical Information of China (English)

    汪芸; 顾冠群

    1997-01-01

    QOS(Quality Of Service)parameter definitions are the basis of further QOS control.But QOS parameters defined by organizations such as ISO and ITU are incoherent and incompatible.It leads to the imefficiency of QOS controls.Based on the analysis of QOS parameters defined by ISO and ITU,this paper first promotes Minimum QOS Parameter Set in transport layer.It demonstrates that the parameters defined by ISO and ITU can be represented b parameters or a combination of parameters of the Set.The paper also expounds that the Set is open and manageable and it can be the potential unified base for QOS parameters.

  10. Geosphere process report for the safety assessment SR-Site

    Energy Technology Data Exchange (ETDEWEB)

    Skagius, Kristina (ed.) (Kemakta Konsult AB, Stockholm (Sweden))

    2010-11-15

    This report documents geosphere processes identified as relevant to the long-term safety of a KBS-3 repository, and forms an important part of the reporting of the safety assessment SR-Site. The detailed assessment methodology, including the role of the process reports in the assessment, is described in the SR-Site Main report /SKB 2011/

  11. An edge-based unstructured mesh discretisation in geospherical framework

    Science.gov (United States)

    Szmelter, Joanna; Smolarkiewicz, Piotr K.

    2010-07-01

    An arbitrary finite-volume approach is developed for discretising partial differential equations governing fluid flows on the sphere. Unconventionally for unstructured-mesh global models, the governing equations are cast in the anholonomic geospherical framework established in computational meteorology. The resulting discretisation retains proven properties of the geospherical formulation, while it offers the flexibility of unstructured meshes in enabling irregular spatial resolution. The latter allows for a global enhancement of the spatial resolution away from the polar regions as well as for a local mesh refinement. A class of non-oscillatory forward-in-time edge-based solvers is developed and applied to numerical examples of three-dimensional hydrostatic flows, including shallow-water benchmarks, on a rotating sphere.

  12. Optimization parameters system maintenance transport aircraft

    Directory of Open Access Journals (Sweden)

    І.І. Ліннік

    2006-01-01

    Full Text Available  The algorithm of unconditional and conditional optimization Markov models of maintenance systems of transport airplanes of their programs of technical operation used at improvement is considered.

  13. [Sphygmographic parameters in fighter and transport pilots].

    Science.gov (United States)

    Gai, Y; Tian, G; Yu, Y; Zhao, Y; Liang, B

    1997-10-01

    To evaluate and discover hidden cardiovascular trouble in pilots, the cardiovascular function of 129 active male pilots was examined with a new sphygmographic method. 13 pilots (10.3%) were found to have abnormal cardiovascular function. The average arterial blood pressure and medium artery modulus of the fighter pilots aged from 30 to 34 years are inferior to those aged from 25 to 29 obviously, however, that is not the case in transport pilots. This indicates that frequent examination of cardiovascular function with convenient special method is necessary for the improvement of the quality of medical monitor on pilots.

  14. Geosphere process report for the safety assessment SR-Can

    Energy Technology Data Exchange (ETDEWEB)

    Skagius, Kristina [Kemakta Konsult AB, Stockholm (SE)] (ed.)

    2006-09-15

    This report documents geosphere processes identified as relevant to the long-term safety of a KBS- repository, and forms an important part of the reporting of the safety assessment SR-Can. The detailed assessment methodology, including the role of the process report in the assessment, is described in the SR-Can Main report. The following excerpts describe the methodology, and clarify the role of this process report in the assessment. The repository system, broadly defined as the deposited spent nuclear fuel, the engineered barriers surrounding it, the host rock and the biosphere in the proximity of the repository, will evolve over time. Future states of the system will depend on the initial state of the system, a number of radiation related, thermal, hydraulic, mechanical, chemical and biological processes acting within the repository system over time, and external influences acting on the system. A methodology in ten steps has been developed for SR-Can described below. Identification of factors to consider (FEP processing): This step consists of identifying all the factors that need to be included in the analysis. Experience from earlier safety assessments and KBS-specific and international databases of relevant features, events and processes influencing long-term safety are utilised. Based on the results of the FEP processing, an SR-Can FEP catalogue, containing FEPs to be handled in SR-Can, has been established. The initial state of the system is described based on the design specifications of the KBS repository, a descriptive model of the repository site and a site-specific layout of the repository. The initial state of the fuel and the engineered components is that immediately after deposition, as described in the SR-Can Initial state report. The initial state of the geosphere and the biosphere is that of the natural system prior to excavation, as described in the site descriptive models. The repository layouts adapted to the sites are provided in underground

  15. Geosphere process report for the safety assessment SR-Can

    Energy Technology Data Exchange (ETDEWEB)

    Skagius, Kristina [Kemakta Konsult AB, Stockholm (SE)] (ed.)

    2006-09-15

    This report documents geosphere processes identified as relevant to the long-term safety of a KBS- repository, and forms an important part of the reporting of the safety assessment SR-Can. The detailed assessment methodology, including the role of the process report in the assessment, is described in the SR-Can Main report. The following excerpts describe the methodology, and clarify the role of this process report in the assessment. The repository system, broadly defined as the deposited spent nuclear fuel, the engineered barriers surrounding it, the host rock and the biosphere in the proximity of the repository, will evolve over time. Future states of the system will depend on the initial state of the system, a number of radiation related, thermal, hydraulic, mechanical, chemical and biological processes acting within the repository system over time, and external influences acting on the system. A methodology in ten steps has been developed for SR-Can described below. Identification of factors to consider (FEP processing): This step consists of identifying all the factors that need to be included in the analysis. Experience from earlier safety assessments and KBS-specific and international databases of relevant features, events and processes influencing long-term safety are utilised. Based on the results of the FEP processing, an SR-Can FEP catalogue, containing FEPs to be handled in SR-Can, has been established. The initial state of the system is described based on the design specifications of the KBS repository, a descriptive model of the repository site and a site-specific layout of the repository. The initial state of the fuel and the engineered components is that immediately after deposition, as described in the SR-Can Initial state report. The initial state of the geosphere and the biosphere is that of the natural system prior to excavation, as described in the site descriptive models. The repository layouts adapted to the sites are provided in underground

  16. Where does the Thermospheric Ionospheric GEospheric Research (TIGER) Program go?

    Science.gov (United States)

    Schmidtke, G.; Avakyan, S. V.; Berdermann, J.; Bothmer, V.; Cessateur, G.; Ciraolo, L.; Didkovsky, L.; Dudok de Wit, T.; Eparvier, F. G.; Gottwald, A.; Haberreiter, M.; Hammer, R.; Jacobi, Ch.; Jakowski, N.; Kretzschmar, M.; Lilensten, J.; Pfeifer, M.; Radicella, S. M.; Schäfer, R.; Schmidt, W.; Solomon, S. C.; Thuillier, G.; Tobiska, W. K.; Wieman, S.; Woods, T. N.

    2015-10-01

    At the 10th Thermospheric Ionospheric GEospheric Research (TIGER/COSPAR) symposium held in Moscow in 2014 the achievements from the start of TIGER in 1998 were summarized. During that period, great progress was made in measuring, understanding, and modeling the highly variable UV-Soft X-ray (XUV) solar spectral irradiance (SSI), and its effects on the upper atmosphere. However, after more than 50 years of work the radiometric accuracy of SSI observation is still an issue and requires further improvement. Based on the extreme ultraviolet (EUV) data from the SOLAR/SolACES, and SDO/EVE instruments, we present a combined data set for the spectral range from 16.5 to 105.5 nm covering a period of 3.5 years from 2011 through mid of 2014. This data set is used in ionospheric modeling of the global Total Electron Content (TEC), and in validating EUV SSI modeling. For further investigations the period of 3.5 years is being extended to about 12 years by including data from SOHO/SEM and TIMED/SEE instruments. Similarly, UV data are used in modeling activities. After summarizing the results, concepts are proposed for future real-time SSI measurements with in-flight calibration as experienced with the ISS SOLAR payload, for the development of a space weather camera for observing and investigating space weather phenomena in real-time, and for providing data sets for SSI and climate modeling. Other planned topics are the investigation of the relationship between solar EUV/UV and visible/near-infrared emissions, the impact of X-rays on the upper atmosphere, the development of solar EUV/UV indices for different applications, and establishing a shared TIGER data system for EUV/UV SSI data distribution and real-time streaming, also taking into account the achievements of the FP7 SOLID (First European SOLar Irradiance Data Exploitation) project. For further progress it is imperative that coordinating activities in this special field of solar-terrestrial relations and solar physics is

  17. Local measurement of transport parameters for laser injected trace impurities

    Energy Technology Data Exchange (ETDEWEB)

    Giannella, R.; Lauro-Taroni, L. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking

    1994-07-01

    A procedure has been developed that determines local measurements of transport parameters`s profiles for injected impurities. The measured profiles extend from the plasma centre up to a certain radial position (usually {rho} = 0.6-0.7). In the outer region of the plasma the procedure supplies ``most suitable extensions`` up to the plasma edge of the measured transport profiles. The procedure intrinsically assures consistency and excellent agreement between the simulated and experimental data of local broad band soft X-ray emissivity and intensities of individual emission lines from different ion states of the injected impurities. 4 refs., 3 figs.

  18. Error estimation and adaptivity for transport problems with uncertain parameters

    Science.gov (United States)

    Sahni, Onkar; Li, Jason; Oberai, Assad

    2016-11-01

    Stochastic partial differential equations (PDEs) with uncertain parameters and source terms arise in many transport problems. In this study, we develop and apply an adaptive approach based on the variational multiscale (VMS) formulation for discretizing stochastic PDEs. In this approach we employ finite elements in the physical domain and generalize polynomial chaos based spectral basis in the stochastic domain. We demonstrate our approach on non-trivial transport problems where the uncertain parameters are such that the advective and diffusive regimes are spanned in the stochastic domain. We show that the proposed method is effective as a local error estimator in quantifying the element-wise error and in driving adaptivity in the physical and stochastic domains. We will also indicate how this approach may be extended to the Navier-Stokes equations. NSF Award 1350454 (CAREER).

  19. Environmental Transport Input Parameters for the Biosphere Model

    Energy Technology Data Exchange (ETDEWEB)

    M. A. Wasiolek

    2003-06-27

    This analysis report is one of the technical reports documenting the Environmental Radiation Model for Yucca Mountain Nevada (ERMYN), a biosphere model supporting the total system performance assessment (TSPA) for the geologic repository at Yucca Mountain. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows relationships among the reports developed for biosphere modeling and biosphere abstraction products for the TSPA, as identified in the ''Technical Work Plan: for Biosphere Modeling and Expert Support'' (TWP) (BSC 2003 [163602]). Some documents in Figure 1-1 may be under development and not available when this report is issued. This figure provides an understanding of how this report contributes to biosphere modeling in support of the license application (LA), but access to the listed documents is not required to understand the contents of this report. This report is one of the reports that develops input parameter values for the biosphere model. The ''Biosphere Model Report'' (BSC 2003 [160699]) describes the conceptual model, the mathematical model, and the input parameters. The purpose of this analysis is to develop biosphere model parameter values related to radionuclide transport and accumulation in the environment. These parameters support calculations of radionuclide concentrations in the environmental media (e.g., soil, crops, animal products, and air) resulting from a given radionuclide concentration at the source of contamination (i.e., either in groundwater or volcanic ash). The analysis was performed in accordance with the TWP (BSC 2003 [163602]). This analysis develops values of parameters associated with many features, events, and processes (FEPs) applicable to the reference biosphere (DTN: M00303SEPFEPS2.000 [162452]), which are addressed in the biosphere model (BSC 2003 [160699]). The treatment of these FEPs is described in BSC (2003 [160699

  20. PASSENGER SERVICE QUALITY PARAMETERS ASSESSMENT AT TRANSPORT INTERCHANGE HUBS

    Directory of Open Access Journals (Sweden)

    Kozlov Pavel Igorevich

    2017-05-01

    Full Text Available The article discusses a quality assessment method for transport decisions made in transport interchange hubs. Analysis of domestic regulatory documentation and international experience on this subject is performed. It is stated that the domestic regulatory documentation lacks such method of assessment. Special attention is paid to study of pedestrian flows in interchange complexes of intermodal transport interchange hubs. The aim of the study is development of the Level of Service comprehensive assessment criterion by analogy with the international practice. The authors propose to use the queueing theory with elements of the theory of graphs, techniques and regularities that underlie the Level of Service (service factor applied in planning and location of TIH in the USA as well as data from field surveys carried out by the pedestrian flows video detection method. During the field surveys it is planned to perform analysis of external and internal factors influencing the formation and composition of a pedestrian flow, to determine quantitative values of the main parameters of pedestrian flow (density, speed, intensity and regularities of their variation depending on the design features of pedestrian traffic environment. Determination of passenger service quality factors in TIH will help to develop an integral criterion based on the Level of Service, taking into account the specifics of TIH functioning in Russia as well as a methodology that allows a reasonable choice of combinations of structural elements and planning parameters of pedestrian traffic objects which will let to reduce construction costs and operating costs for location of interchange complexes.

  1. Deducing effective light transport parameters in optically thin systems

    CERN Document Server

    Mazzamuto, Giacomo; Toninelli, Costanza; Wiersma, Diederik

    2015-01-01

    We present an extensive Monte Carlo study on light transport in optically thin slabs, addressing both axial and transverse propagation. We completely characterize the so-called ballistic-to-diffusive transition, notably in terms of the spatial variance of the transmitted/reflected profile. We test the validity of the prediction cast by diffusion theory, that the spatial variance should grow independently of absorption and, to a first approximation, of the sample thickness and refractive index contrast. Based on a large set of simulated data, we build a freely available look-up table routine allowing reliable and precise determination of the microscopic transport parameters starting from robust observables which are independent of absolute intensity measurements. We also present the Monte Carlo software package that was developed for the purpose of this study.

  2. The importance of transport parameter cross correlations in natural systems radioactive transport models

    Energy Technology Data Exchange (ETDEWEB)

    Reimus, Paul W [Los Alamos National Laboratory

    2011-01-03

    Transport parameter cross correlations are rarely considered in models used to predict radionuclide transport in natural systems. In this paper, it is shown that parameter cross correlations could have a significant impact on radionuclide transport predictions in saturated media. In fractured rock, the positive correlation between fracture apertures and groundwater residence times is shown to result in significantly less retardation due to matrix diffusion than is predicted without the correlation. The suppression of matrix diffusion is further amplified by a tendency toward larger apertures, smaller matrix diffusion coefficients, and less sorption capacity in rocks of lower matrix porosity. In a hypothetical example, strong cross correlations between these parameters result in a decrease in predicted radionuclide travel times of an order of magnitude or more relative to travel times calculated with uncorrelated parameters. In porous media, expected correlations between permeability, porosity, and sorption capacity also result in shorter predicted travel times than when the parameters are assumed to be uncorrelated. Individual parameter standard deviations can also have a significant influence on predicted radionuclide travel times, particularly when cross correlations are considered.

  3. Study of some parameters interstellar transport using of magnetic umbrella

    CERN Document Server

    Čermák, Martin

    2013-01-01

    Interstellar transport is an object of interest in many sci-fi stories. In history a lot of sci-fi predictions have turned into reality, such as communications satellites, deep-sea submarines and journies to the moon. In this work we study some physical parameters of a space ship which uses a magnetic umbrella. Our spaceship generates a magnetic field in its neighborhood and captures charged protons into a magnetic trap. These particles are taken into a fusion reactor. The obtained energy and waste in form of helium are used as a fuel in an ion engine. With the help of elementary physics we can work out the basic physical parameters of the ship, e.g. maximal velocity, acceleration of the ship or acceleration time period.

  4. Environmental Transport Input Parameters for the Biosphere Model

    Energy Technology Data Exchange (ETDEWEB)

    M. Wasiolek

    2004-09-10

    This analysis report is one of the technical reports documenting the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), a biosphere model supporting the total system performance assessment for the license application (TSPA-LA) for the geologic repository at Yucca Mountain. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows relationships among the reports developed for biosphere modeling and biosphere abstraction products for the TSPA-LA, as identified in the ''Technical Work Plan for Biosphere Modeling and Expert Support'' (BSC 2004 [DIRS 169573]) (TWP). This figure provides an understanding of how this report contributes to biosphere modeling in support of the license application (LA). This report is one of the five reports that develop input parameter values for the biosphere model. The ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) describes the conceptual model and the mathematical model. The input parameter reports, shown to the right of the Biosphere Model Report in Figure 1-1, contain detailed description of the model input parameters. The output of this report is used as direct input in the ''Nominal Performance Biosphere Dose Conversion Factor Analysis'' and in the ''Disruptive Event Biosphere Dose Conversion Factor Analysis'' that calculate the values of biosphere dose conversion factors (BDCFs) for the groundwater and volcanic ash exposure scenarios, respectively. The purpose of this analysis was to develop biosphere model parameter values related to radionuclide transport and accumulation in the environment. These parameters support calculations of radionuclide concentrations in the environmental media (e.g., soil, crops, animal products, and air) resulting from a given radionuclide concentration at the source of contamination (i.e., either in groundwater or in volcanic ash). The analysis

  5. Noosphere as Optimal Control. Part 1. Control Theory, Geosphere and Biosphere

    Directory of Open Access Journals (Sweden)

    Boris Balter

    2017-09-01

    Full Text Available The conceptual system developed in optimal control theory for technical purposes is used as a philosophical instrument applied to cyclic information processes, which are expected to be the basis of noosphere. Noosphere was perceived by the founding fathers of this concept, Vladimir Vernadsky, Pierre Teilhard de Chardin, e.a. as an outgrowth of the evolutionary process, which begins with cosmogenesis and proceeds through geosphere and biosphere. We attempt to apply the optimal control concepts to all three levels — geospheric, biospheric, and noospheric — due to their having a common structure of information processes (or entropic processes considered as proto-information. These processes include homeostasis, accumulation and expenditure of information, formation of hierarchical information structures, evolution involving the breaks of homeostasis etc. In noosphere, controlled system may have the same informational capabilities as controlling system, so that the term “dialog” is more adequate; in this case, we extend optimal control description to game theory. The cyclic, feedback logic of optimal control seems better adapted to noospheric processes than usual cause-eff ect logic. The fi rst part of the paper considers the geospheric and biospheric level. We introduce the basic notions characterizing optimal control cycle: duality of observation and control, hierarchy of models, active sounding, balance of information infl ow and outfl ow, optimized criterion, networked (distributed control, etc. Then, natural homeostases at the geospheric level are considered as a form of self-regulation having specifi c optimized criteria. The constitutive feature of this level is the absence of information processing in the strict sense: its place is taken by entropic processes. Therefore, no goal can exist at this level, and we consider it as a part of cosmogenesis, which is allegedly goalless/meaningless. We discuss the anthropic principle as a means

  6. Hole transport parameters in a PTOPT based organic solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Gebremichael, B. [Addis Ababa Univ., Addis Ababa (Ethiopia). Dept. of Physics; Tessema, G. [Addis Ababa Univ., Addis Ababa (Ethiopia). Dept. of Physics; National Univ. of Lesotho (Lesotho). Dept. of Physics and Electronics

    2010-05-15

    Semiconductor polymers are light-weight and inexpensive to manufacture. As such, they are in demand for solar cell applications. In this study, a single layer photovoltaic (PV) device was used to examine the charge transport phenomena in a photoactive layer made of poly[3-(4-octylphenyl)-2, 2{sup '}-bithiophene] (PTOPT). The devices were prepared in a sandwich-type structure of the form Al/PTOPT/PEDOT:PSS/ITO. The diodes exhibited good rectification which is required in a PV cell. The device rectified at room temperature and lost rectification at around 273 K. The loss of rectification at low temperatures was due to the injection of holes from the aluminium electrode that rendered the device hole-dominated. The symmetric nature of the semilogarithmic J-V plot under dark and low temperature demonstrated that there is a unipolar charge injection in both sides of the electrodes. Based on the space charge limited region J-V data, it was possible to examine the electric field dependence of the hole transport. Important parameters such as the zero field mobility and the field activation factor were then derived. 9 refs., 4 figs.

  7. Recent developments in assessment of long-term radionuclide behavior in the geosphere-biosphere subsystem.

    Science.gov (United States)

    Smith, G M; Smith, K L; Kowe, R; Pérez-Sánchez, D; Thorne, M; Thiry, Y; Read, D; Molinero, J

    2014-05-01

    Decisions on permitting, controlling and monitoring releases of radioactivity into the environment rely on a great variety of factors. Important among these is the prospective assessment of radionuclide behavior in the environment, including migration and accumulation among and within specific environmental media, and the resulting environmental and human health impacts. Models and techniques to undertake such assessments have been developed over several decades based on knowledge of the ecosystems involved, as well as monitoring of previous radionuclide releases to the environment, laboratory experiments and other related research. This paper presents developments in the assessment of radiation doses and related research for some of the key radionuclides identified as of potential significance in the context of releases to the biosphere from disposal facilities for solid radioactive waste. Since releases to the biosphere from disposal facilities involve transfers from the geosphere to the biosphere, an important aspect is the combined effects of surface hydrology, near-surface hydrogeology and chemical gradients on speciation and radionuclide mobility in the zone in which the geosphere and biosphere overlap (herein described as the geosphere-biosphere subsystem). In turn, these aspects of the environment can be modified as a result of environmental change over the thousands of years that have to be considered in radioactive waste disposal safety assessments. Building on the experience from improved understanding of the behavior of the key radionuclides, this paper proceeds to describe development of a generic methodology for representing the processes and environmental changes that are characteristic of the interface between the geosphere and the biosphere. The information that is provided and the methodology that is described are based on international collaborative work implemented through the BIOPROTA forum, www.bioprota.org.

  8. Geosphere coupling and hydrothermal anomalies before the 2009 Mw 6.3 L'Aquila earthquake in Italy

    Science.gov (United States)

    Wu, Lixin; Zheng, Shuo; De Santis, Angelo; Qin, Kai; Di Mauro, Rosa; Liu, Shanjun; Rainone, Mario Luigi

    2016-08-01

    The earthquake anomalies associated with the 6 April 2009 Mw 6.3 L'Aquila earthquake have been widely reported. Nevertheless, the reported anomalies have not been so far synergically analyzed to interpret or prove the potential lithosphere-coversphere-atmosphere coupling (LCAC) process. Previous studies on b value (a seismicity parameter from Gutenberg-Richter law) are also insufficient. In this work, the spatiotemporal evolution of several hydrothermal parameters related to the coversphere and atmosphere, including soil moisture, soil temperature, near-surface air temperature, and precipitable water, was comprehensively investigated. Air temperature and atmospheric aerosol were also statistically analyzed in time series with ground observations. An abnormal enhancement of aerosol occurred on 30 March 2009 and thus proved quasi-synchronous anomalies among the hydrothermal parameters from 29 to 31 March in particular places geo-related to tectonic thrusts and local topography. The three-dimensional (3-D) visualization analysis of b value revealed that regional stress accumulated to a high level, particularly in the L'Aquila basin and around regional large thrusts. Finally, the coupling effects of geospheres were discussed, and a conceptual LCAC mode was proposed to interpret the possible mechanisms of the multiple quasi-synchronous anomalies preceding the L'Aquila earthquake. Results indicate that CO2-rich fluids in deep crust might have played a significant role in the local LCAC process.

  9. Hydrogen isotopes transport parameters in fusion reactor materials

    Energy Technology Data Exchange (ETDEWEB)

    Serra, E. [Politecnico di Torino (Italy). Dipartimento di Energetica; Benamati, G. [ENEA Fusion Division, CR Brasimone, 40032 Camungnano, Bologna (Italy); Ogorodnikova, O.V. [Moscow State Engineering Physics Institute, Moscow 115409 (Russian Federation)

    1998-06-01

    This work presents a review of hydrogen isotopes-materials interactions in various materials of interest for fusion reactors. The relevant parameters cover mainly diffusivity, solubility, trap concentration and energy difference between trap and solution sites. The list of materials includes the martensitic steels (MANET, Batman and F82H-mod.), beryllium, aluminium, beryllium oxide, aluminium oxide, copper, tungsten and molybdenum. Some experimental work on the parameters that describe the surface effects is also mentioned. (orig.) 62 refs.

  10. Radiation Effects on the Sorption and Mobilization of Radionuclide during Transport through the Geosphere

    Energy Technology Data Exchange (ETDEWEB)

    L.M. Wang; R.C. Eqing; K.F. Hayes

    2004-03-14

    Site restoration activities at DOE facilities and the permanent disposal of nuclear waste inevitably involve understanding the behavior of materials in a radiation field. Radionuclide decay and the associated radiation fields lead to physical and chemical changes that can degrade or enhance important material properties. Alpha-decay of the actinide elements and beta-decay of the fission products lead to atomic-scale changes in materials (radiation damage and transmutation).

  11. Hydrothermal anomalies before the 2009 Mw 6.3 L'Aquila earthquake in Italy referring to the geospheres coupling effects

    Science.gov (United States)

    Wu, Lixin; Zheng, Shuo; Qin, Kai; De Santis, Angelo; Liu, Shanjun

    2016-04-01

    A large number of precursory anomalies of the 2009 L'Aquila EQ were reported after the shocking, including thermal properties, electric and magnetic fields, gas emissions and seismicity. Previous studies on the seismic b-value are also insufficient, which is possibly a proxy of crust stress conditions and could therewith act as a crude stress-meter wherever seismicity is observed in lithosphere. Nevertheless, the reported anomalies have not been so far synergically analyzed to interpret or prove the potential coupling process among different geospheres. In this paper, the spatio-temporal evolution of several hydrothermal parameters related to the coversphere and atmosphere, including soil moisture, soil temperature, near-surface air temperature, and precipitable water, was comprehensively investigated. Air temperature and atmospheric aerosol were also statistically analyzed in time series with ground observations. An abnormal enhancement of aerosol occurred on March 30, 2009 and thus proved quasi-synchronous anomalies among the hydrothermal parameters from March 29 to 31 in particular places geo-related to tectonic thrusts and local topography. In additional, the three-dimensional (3D) visualization analysis of b-value revealed that regional stress accumulated to a high level, particularly in the L'Aquila basin and around regional large thrusts. This links logically and spatially the multiple observations on coversphere and atmosphere with that on lithosphere. Finally, the coupling effects of geospheres were discussed, and a conceptual LCA coupling mode was proposed to interpret the possible mechanisms of the multiple quasi-synchronous anomalies preceding the L'Aquila EQ. Results indicate that CO2-rich fluids in deep crust might have played a significant role in the local LCA coupling process.

  12. Correlating substituent parameter values to electron transport properties of molecules

    Science.gov (United States)

    Vedova-Brook, Natalie; Matsunaga, Nikita; Sohlberg, Karl

    2004-03-01

    There are a vast number of organic compounds that could be considered for use in molecular electronics. Because of this, the need for efficient and economical screening tools has emerged. We demonstrate that the substituent parameter values ( σ), commonly found in advanced organic chemistry textbooks, correlate strongly with features of the charge migration process, establishing them as useful indicators of electronic properties. Specifically, we report that ab initio derived electronic charge transfer values for 16 different substituted aromatic molecules for molecular junctions correlate to the σ values with a correlation coefficient squared ( R2) of 0.863.

  13. Experimental Studies of the Transport Parameters of Warm Dense Matter

    Energy Technology Data Exchange (ETDEWEB)

    Chouffani, Khalid [Idaho State Univ., Pocatello, ID (United States)

    2014-12-01

    There is a need to establish fundamental properties of matter and energy under extreme physical conditions. Although high energy density physics (HEDP) research spans a wide range of plasma conditions, there is one unifying regime that is of particular importance and complexity: that of warm dense matter, the transitional state between solid state condensed matter and energetic plasmas. Most laboratory experimental conditions, including inertial confinement implosion, fall into this regime. Because all aspects of laboratory-created high-energy-density plasmas transition through the warm dense matter regime, understanding the fundamental properties to determine how matter and energy interact in this regime is an important aspect of major research efforts in HEDP. Improved understanding of warm dense matter would have significant and wide-ranging impact on HEDP science, from helping to explain wire initiation studies on the Sandia Z machine to increasing the predictive power of inertial confinement fusion modeling. The central goal or objective of our proposed research is to experimentally determine the electrical resistivity, temperature, density, and average ionization state of a variety of materials in the warm dense matter regime, without the use of theoretical calculations. Since the lack of an accurate energy of state (EOS) model is primarily due to the lack of experimental data, we propose an experimental study of the transport coefficients of warm dense matter.

  14. Optimal Bayesian experimental design for contaminant transport parameter estimation

    CERN Document Server

    Tsilifis, Panagiotis; Hajali, Paris

    2015-01-01

    Experimental design is crucial for inference where limitations in the data collection procedure are present due to cost or other restrictions. Optimal experimental designs determine parameters that in some appropriate sense make the data the most informative possible. In a Bayesian setting this is translated to updating to the best possible posterior. Information theoretic arguments have led to the formation of the expected information gain as a design criterion. This can be evaluated mainly by Monte Carlo sampling and maximized by using stochastic approximation methods, both known for being computationally expensive tasks. We propose an alternative framework where a lower bound of the expected information gain is used as the design criterion. In addition to alleviating the computational burden, this also addresses issues concerning estimation bias. The problem of permeability inference in a large contaminated area is used to demonstrate the validity of our approach where we employ the massively parallel vers...

  15. Development of COLLAGE 3; Role for colloids in the transport of radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Klos, Richard (Aleksandria Sciences, Sheffield (United Kingdom)); Bath, Adrian (Intellisci Ltd., Loughborough (United Kingdom))

    2010-03-15

    The issue of colloid-facilitated radionuclide transport (CFRT) was last addressed by the Swedish nuclear regulators in 2001 - 2002. SKI had commissioned the Collage code with subsequent development as Collage 2. This code was employed to investigate the potential role for colloids to have been involved in the transport of radionuclides at the Nevada Test Site and to examine the implications for CFRT in the Swedish disposal programme. It was concluded that colloids could not be ruled out as a mechanism for rapid transport and early release from the geosphere. Recently the 'bentonite erosion scenario' has become of concern. In it the generation of large quantities of bentonite colloids in fractures as a result of fresh water ingress at repository depth is possible. Potentially, these could carry radiologically significant quantities of radionuclides to an early release to the surface system. The objectives of this work are to update the knowledge of colloid-facilitated radionuclide transport through a fractured geosphere and to provide review capability within the SSM. Recent developments in CFRT (reviewed here) indicate that additional parameters needed to be added to the existing Collage 2 plus code in order to adequately represent colloid transport in fractures. This report looks at modifications to the model and discusses the implications of the implementation of the new processes. Authors conclude that the process of colloid filtration is an important mitigating mechanism. A new code - Collage 3 - is demonstrated and suggestions for further work are given

  16. Dual-tracer transport experiments in a physically and chemically heterogeneous porous aquifer: effective transport parameters and spatial variability

    Science.gov (United States)

    Ptak, T.; Schmid, G.

    1996-08-01

    In order to investigate the effects of reactive transport processes within a heterogeneous porous aquifer, two small-scale forced gradient tracer tests were conducted at the 'Horkheimer Insel' field site. During the experiments, two fluorescent tracers were injected simultaneously in the same fully penetrating groundwater monitoring well, located approximately 10 m from the pumping well. Fluoresceine and Rhodamine WT were used to represent the classes of practically non-sorbing and sorbing solutes, respectively. Multilevel breakthrough curves with a temporal resolution of 1 min were measured for both tracers at different depths within the pumping well using fibre-optic fluorimeters. This paper presents the tracer test design, the fibre-optic fluorimetry instrumentation, the experimental results and the interpretation of the measured multilevel breakthrough curves in terms of temporal moments and effective transport parameters. Significant sorption of Rhodamine WT is apparent from the effective retardation factors. Furthermore, an enhanced tailing of Rhodamine WT breakthrough curves is observed, which is possibly caused by a variability of aquifer sorption properties. The determined effective parameters are spatially variable, suggesting that a complex numerical flow and transport modelling approach within a stochastic framework will be needed to adequately describe the transport behaviour observed in the two experiments. Therefore, the tracer test results will serve in future work for the validation of numerical stochastic transport simulations taking into account the spatial variability of hydraulic conductivity and sorption-related aquifer properties.

  17. The international geosphere biosphere programme data and information system global land cover data set (DIScover)

    Science.gov (United States)

    Loveland, T.R.; Belward, A.S.

    1997-01-01

    The International Geosphere Biosphere Programme Data and Information System (IGBP-DIS), through the mapping expertise of the U.S. Geological Survey and the European Commission's Joint Research Centre, recently guided the completion of a 1-km resolution global land cover data set from advanced very high resolution radiometer (AVHRR) data. The 1-km resolution land cover product, 'DISCover,' was based on monthly normalized difference vegetation index composites from 1992 and 1993. The development of DISCover was coordinated by the IGBP-DIS Land Cover Working Group as part of the IGBP-DIS Focus 1 activity. DISCover is a 17-class land cover data set based on the scientific requirements of IGBP elements. The mapping used unsupervised classification and postclassification refinement using ancillary data. The development of this data set was motivated by the need for global land cover data with higher spatial resolution, improved temporal specificity, and known classification accuracy. The completed DISCover data set will soon be validated to determine the accuracy of the global classification.

  18. The seventh international conference on the chemistry and migration behavior of actinides and fission products in the Geosphere MIGRATION'99 abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, C

    1999-09-01

    The Migration conferences focus on recent developments in the fundamental chemistry of actinides and fission products in natural aquifer systems, their interactions and migration in the geosphere, and the processes involved in modeling their geochemical behavior. The primary mode dissemination of technical information will be early evening poster sessions designed to encourage intensive communication between the authors and participants. Daily oral sessions will be opened with invited lectures followed by contributed papers within the scope of each session. Sessions cover: (A) Chemistry of actinides and fission products in natural aquatic systems: (1) Solubilities and dissolution reactions; (2) Complexation with inorganic and organic ligands; (3) Redox reactions; (4) Colloid formation; and (5) Experimental methods. (B) Geochemical interactions and transport phenomena: (1) Diffusion and migration in geologic media; (2) Sorption/desorption phenomena; (3) Natural analog studies; (4) Effects of biological activities and organic materials; (5) Colloid transport; (6) Radionuclides in soils; and (7) Soil-remediation chemistries. (C) Data base development and modeling: (1) Data selection and evaluation; (2) Data base management; (3) Geochemical models and modeling; (4) Application of models; and (5) Validation of modeling results.

  19. Safety in intrahospital transportation: evaluation of respiratory and hemodynamic parameters. A prospective cohort study

    Directory of Open Access Journals (Sweden)

    Bruno Franco Mazza

    Full Text Available CONTEXT AND OBJECTIVE: Intrahospital transportation of mechanically ventilated patients is a high-risk situation. We aimed to determine whether transfers could be safely performed by using a transportation routine. DESIGN AND SETTING: Prospective cohort study with "before and after" evaluation. METHODS: Mechanically ventilated patients who needed transportation were included. Hemodynamic and respiratory parameters were measured before and after transportation. Statistical analysis consisted of variance analysis and paired Student's t test. Results were considered significant if P 5, FiO2 > 0.4 and vasoactive drug use comprised 42.4%, 24.3%, 21.6% and 33.0% of cases, respectively. Mean duration of transportation was 43.4 ± 18.9 minutes. Complications occurred in 32.4%. There was a significant increase in CO2 (before transportation, 29.6 ± 7.3 and after transportation, 34.9 ± 7.0; P = 0.000; a trend towards improved PO2/FiO2 ratio (before transportation, 318.0 ± 137.0 and after transportation, 356.8 ± 119.9; P = 0.053; increased heart rate (before transportation, 80.9 ± 18.7 and after transportation, 85.5 ± 17.6; P = 0.08; and no significant change in mean arterial blood pressure (P = 0.93. CONCLUSION: These results suggest that intrahospital transportation can be safely performed. Our low incidence of complications was possibly related to both the presence of a multidisciplinary transportation team and proper equipment.

  20. Estimation of light transport parameters in biological media using coherent backscattering

    Indian Academy of Sciences (India)

    S Anantha Ramakrishna; K Divakara Rao

    2000-02-01

    The suitability of using the angular peak shape of the coherent backscattered light for estimating the light transport parameters of biological media has been investigated. Milk and methylene blue doped milk were used as tissue phantoms for the measurements carried out with a He–Ne laser (632.8 nm). Results indicate that while the technique accurately estimates the transport length, it can determine the absorption coefficient only when the absorption is moderately high ( > 1 cm-1) for the long transport lengths typical of tissues. Further, the possibility of determining the anisotropy factor by estimating the single scattering contribution to the diffuse background is examined.

  1. Global sensitivity analysis and Bayesian parameter inference for solute transport in porous media colonized by biofilms

    Science.gov (United States)

    Younes, A.; Delay, F.; Fajraoui, N.; Fahs, M.; Mara, T. A.

    2016-08-01

    The concept of dual flowing continuum is a promising approach for modeling solute transport in porous media that includes biofilm phases. The highly dispersed transit time distributions often generated by these media are taken into consideration by simply stipulating that advection-dispersion transport occurs through both the porous and the biofilm phases. Both phases are coupled but assigned with contrasting hydrodynamic properties. However, the dual flowing continuum suffers from intrinsic equifinality in the sense that the outlet solute concentration can be the result of several parameter sets of the two flowing phases. To assess the applicability of the dual flowing continuum, we investigate how the model behaves with respect to its parameters. For the purpose of this study, a Global Sensitivity Analysis (GSA) and a Statistical Calibration (SC) of model parameters are performed for two transport scenarios that differ by the strength of interaction between the flowing phases. The GSA is shown to be a valuable tool to understand how the complex system behaves. The results indicate that the rate of mass transfer between the two phases is a key parameter of the model behavior and influences the identifiability of the other parameters. For weak mass exchanges, the output concentration is mainly controlled by the velocity in the porous medium and by the porosity of both flowing phases. In the case of large mass exchanges, the kinetics of this exchange also controls the output concentration. The SC results show that transport with large mass exchange between the flowing phases is more likely affected by equifinality than transport with weak exchange. The SC also indicates that weakly sensitive parameters, such as the dispersion in each phase, can be accurately identified. Removing them from calibration procedures is not recommended because it might result in biased estimations of the highly sensitive parameters.

  2. Recommended direct simulation Monte Carlo collision model parameters for modeling ionized air transport processes

    Energy Technology Data Exchange (ETDEWEB)

    Swaminathan-Gopalan, Krishnan; Stephani, Kelly A., E-mail: ksteph@illinois.edu [Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

    2016-02-15

    A systematic approach for calibrating the direct simulation Monte Carlo (DSMC) collision model parameters to achieve consistency in the transport processes is presented. The DSMC collision cross section model parameters are calibrated for high temperature atmospheric conditions by matching the collision integrals from DSMC against ab initio based collision integrals that are currently employed in the Langley Aerothermodynamic Upwind Relaxation Algorithm (LAURA) and Data Parallel Line Relaxation (DPLR) high temperature computational fluid dynamics solvers. The DSMC parameter values are computed for the widely used Variable Hard Sphere (VHS) and the Variable Soft Sphere (VSS) models using the collision-specific pairing approach. The recommended best-fit VHS/VSS parameter values are provided over a temperature range of 1000-20 000 K for a thirteen-species ionized air mixture. Use of the VSS model is necessary to achieve consistency in transport processes of ionized gases. The agreement of the VSS model transport properties with the transport properties as determined by the ab initio collision integral fits was found to be within 6% in the entire temperature range, regardless of the composition of the mixture. The recommended model parameter values can be readily applied to any gas mixture involving binary collisional interactions between the chemical species presented for the specified temperature range.

  3. Sensitivity analysis of the SWMM Runoff-Transport parameters and the effects of catchment discretisation

    Science.gov (United States)

    Zaghloul, Nabil A.

    The use of the SWMM model to simulate the Runoff-Transport phenomenon necessitates the proper calibration of the different parameters involved in the process and the effect of these parameters on the routed hydrograph. A detailed sensitivity analysis is conducted on the main parameters of the Runoff-Transport Blocks to establish which are the most sensitive parameters affecting the Runoff-Transport simulation. The result of the study indicates a relative influence of the major parameters used in both the Runoff and Transport Blocks. Hence, the SWMM default values can be used adequately. The costs of setting up and running a SWMM simulation are largely determined by the level of discretisation used for a particular catchment. The purpose of this part of the study is to investigate the level of discretisation needed to adequately represent an urban watershed and to illustrate the effects of reducing the number of subcatchments on the accuracy of runoff simulation. A methodology is defined to achieve a representative equivalent catchment from theoretical considerations. Verification of the procedures involved a series of applications on both hypothetical and real areas.

  4. Recommended direct simulation Monte Carlo collision model parameters for modeling ionized air transport processes

    Science.gov (United States)

    Swaminathan-Gopalan, Krishnan; Stephani, Kelly A.

    2016-02-01

    A systematic approach for calibrating the direct simulation Monte Carlo (DSMC) collision model parameters to achieve consistency in the transport processes is presented. The DSMC collision cross section model parameters are calibrated for high temperature atmospheric conditions by matching the collision integrals from DSMC against ab initio based collision integrals that are currently employed in the Langley Aerothermodynamic Upwind Relaxation Algorithm (LAURA) and Data Parallel Line Relaxation (DPLR) high temperature computational fluid dynamics solvers. The DSMC parameter values are computed for the widely used Variable Hard Sphere (VHS) and the Variable Soft Sphere (VSS) models using the collision-specific pairing approach. The recommended best-fit VHS/VSS parameter values are provided over a temperature range of 1000-20 000 K for a thirteen-species ionized air mixture. Use of the VSS model is necessary to achieve consistency in transport processes of ionized gases. The agreement of the VSS model transport properties with the transport properties as determined by the ab initio collision integral fits was found to be within 6% in the entire temperature range, regardless of the composition of the mixture. The recommended model parameter values can be readily applied to any gas mixture involving binary collisional interactions between the chemical species presented for the specified temperature range.

  5. Characterization of solute transport parameters in leach ore:inverse modeling based on column experiments

    Institute of Scientific and Technical Information of China (English)

    Sheng PENG

    2009-01-01

    Heap leaching is essentially a process in which metals are extracted from mine ores with lixiant. For a better understanding and modeling of this process, solute transport parameters are required to characterize the solute transport system of the leach heap. For porous media like leach ores, which contain substantial gravelly particles and have a broad range of particle size distributions, traditional small-scale laboratory experimental apparatus is not appropriate. In this paper, a 2.44m long, 0.3 m inner diameter column was used for tracer test with boron as the tracer. Tracer tests were conducted for 2 bulk densities (1.92 and 1.62g/cm3) and 2 irrigation rates (2 and 5 L/(mE. h-i)). Inverse modeling with two-region transport model using computer code CXTFIT was conducted based on the measured breakthrough curves to estimate the transport parameters. Fitting was focused on three parameters: dispersion coefficient D, partition coefficient r, and mass transfer coefficient ω. The results turned out to fall within reasonable ranges. Sensitivity analysis was conducted for the three parameters and showed that the order of sensitivity is β > ω > D. In addition, scaling of these parameters was discussed and applied to a real scale heap leach to predict the tracer breakthrough.

  6. Identification of sorption processes and parameters for radionuclide transport in fractured rock

    Science.gov (United States)

    Dai, Zhenxue; Wolfsberg, Andrew; Reimus, Paul; Deng, Hailin; Kwicklis, Edward; Ding, Mei; Ware, Doug; Ye, Ming

    2012-01-01

    SummaryIdentification of chemical reaction processes in subsurface environments is a key issue for reactive transport modeling because simulating different processes requires developing different chemical-mathematical models. In this paper, two sorption processes (equilibrium and kinetics) are considered for modeling neptunium and uranium sorption in fractured rock. Based on different conceptualizations of the two processes occurring in fracture and/or matrix media, seven dual-porosity, multi-component reactive transport models are developed. The process models are identified with a stepwise strategy by using multi-tracer concentration data obtained from a series of transport experiments. In the first step, breakthrough data of a conservative tracer (tritium) obtained from four experiments are used to estimate the flow and non-reactive transport parameters (i.e., mean fluid residence time in fracture, fracture aperture, and matrix tortuosity) common to all the reactive transport models. In the second and third steps, by fixing the common non-reactive flow and transport parameters, the sorption parameters (retardation factor, sorption coefficient, and kinetic rate constant) of each model are estimated using the breakthrough data of reactive tracers, neptunium and uranium, respectively. Based on the inverse modeling results, the seven sorption-process models are discriminated using four model discrimination (or selection) criteria, Akaike information criterion ( AIC), modified Akaike information criterion ( AICc), Bayesian information criterion ( BIC) and Kashyap information criterion ( KIC). These criteria suggest the kinetic sorption process for modeling reactive transport of neptunium and uranium transport in both fracture and matrix. This conclusion is confirmed by two chemical criteria, the half reaction time and Damköhler number criterion.

  7. Geosphere-biosphere interactions in European Protected Areas: a view from the H2020 ECOPOTENTIAL Project

    Science.gov (United States)

    Provenzale, Antonello; Beierkuhnlein, Carl; Karnieli, Arnon; Marangi, Carmela; Giamberini, Mariasilvia; Imperio, Simona

    2017-04-01

    The large H2020 project ECOPOTENTIAL (2015-2019, 47 partners, contributing to GEO and GEOSS - http://www.ecopotential-project.eu/) is devoted to making best use of remote sensing and in situ data to improve future ecosystem benefits, adopting the view of ecosystems as one physical system with their environment, focusing on geosphere-biosphere interactions, Earth Critical Zone dynamics, Macrosystem Ecology and cross-scale interactions, the effect of extreme events and using Essential (Climate, Biodiversity and Ocean) Variables as descriptors of change. In ECOPOTENTIAL, remote sensing and in situ data are collected, processed and used for a better understanding of the ecosystem dynamics, analysing and modelling the effects of global changes on ecosystem functions and services, over an array of different ecosystem types, including mountain, marine, coastal, arid and semi-arid ecosystems. The project focuses on a network of Protected Areas of international relevance, that is representative of the range of environmental and biogeographical conditions characterizing Europe. Some of the activities of the project are devoted to detect and quantify the changes taking place in the Protected Areas, through the analysis of remote sensing observations, in-situ data and gridded climatic datasets. Likewise, the project aims at providing estimates of the future ecosystem conditions in different climate and environmental change scenarios. In all such endeavours, one is faced with cross-scale issues: downscaling of climate information to drive ecosystem response, and upscaling of local ecosystem changes to larger scales. So far, the analysis has been conducted mainly by using traditional methods, but there is wide room for improvement by using more refined approaches. In particular, a crucial question is how to upscale the information gained at single-site scale to larger, regional or continental scale, an issue that could benefit from using, for example, complex network analysis.

  8. Effect of hydraulic parameters on sediment transport capacity in overland flow over erodible beds

    Science.gov (United States)

    Ali, M.; Sterk, G.; Seeger, M.; Boersema, M.; Peters, P.

    2012-02-01

    Sediment transport is an important component of the soil erosion process, which depends on several hydraulic parameters like unit discharge, mean flow velocity, and slope gradient. In most of the previous studies, the impact of these hydraulic parameters on transport capacity was studied for non-erodible bed conditions. Hence, this study aimed to examine the influence of unit discharge, mean flow velocity and slope gradient on sediment transport capacity for erodible beds and also to investigate the relationship between transport capacity and composite force predictors, i.e. shear stress, stream power, unit stream power and effective stream power. In order to accomplish the objectives, experiments were carried out in a 3.0 m long and 0.5 m wide flume using four well sorted sands (0.230, 0.536, 0.719, 1.022 mm). Unit discharges ranging from 0.07 to 2.07 × 10-3 m2 s-1 were simulated inside the flume at four slopes (5.2, 8.7, 13.2 and 17.6%) to analyze their impact on sediment transport rate. The sediment transport rate measured at the bottom end of the flume by taking water and sediment samples was considered equal to sediment transport capacity, because the selected flume length of 3.0 m was found sufficient to reach the transport capacity. The experimental result reveals that the slope gradient has a stronger impact on transport capacity than unit discharge and mean flow velocity due to the fact that the tangential component of gravity force increases with slope gradient. Our results show that unit stream power is an optimal composite force predictor for estimating transport capacity. Stream power and effective stream power can also be successfully related to the transport capacity, however the relations are strongly dependent on grain size. Shear stress showed poor performance, because part of shear stress is dissipated by bed irregularities, bed form evolution and sediment detachment. An empirical transport capacity equation was derived, which illustrates that

  9. Identification of biomolecule mass transport and binding rate parameters in living cells by inverse modeling

    Directory of Open Access Journals (Sweden)

    Shirmohammadi Adel

    2006-10-01

    Full Text Available Abstract Background Quantification of in-vivo biomolecule mass transport and reaction rate parameters from experimental data obtained by Fluorescence Recovery after Photobleaching (FRAP is becoming more important. Methods and results The Osborne-Moré extended version of the Levenberg-Marquardt optimization algorithm was coupled with the experimental data obtained by the Fluorescence Recovery after Photobleaching (FRAP protocol, and the numerical solution of a set of two partial differential equations governing macromolecule mass transport and reaction in living cells, to inversely estimate optimized values of the molecular diffusion coefficient and binding rate parameters of GFP-tagged glucocorticoid receptor. The results indicate that the FRAP protocol provides enough information to estimate one parameter uniquely using a nonlinear optimization technique. Coupling FRAP experimental data with the inverse modeling strategy, one can also uniquely estimate the individual values of the binding rate coefficients if the molecular diffusion coefficient is known. One can also simultaneously estimate the dissociation rate parameter and molecular diffusion coefficient given the pseudo-association rate parameter is known. However, the protocol provides insufficient information for unique simultaneous estimation of three parameters (diffusion coefficient and binding rate parameters owing to the high intercorrelation between the molecular diffusion coefficient and pseudo-association rate parameter. Attempts to estimate macromolecule mass transport and binding rate parameters simultaneously from FRAP data result in misleading conclusions regarding concentrations of free macromolecule and bound complex inside the cell, average binding time per vacant site, average time for diffusion of macromolecules from one site to the next, and slow or rapid mobility of biomolecules in cells. Conclusion To obtain unique values for molecular diffusion coefficient and

  10. A variational approach for dissipative quantum transport in a wide parameter space

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu, E-mail: zhy@yangtze.hku.hk; Kwok, YanHo; Chen, GuanHua, E-mail: ghc@everest.hku.hk [Department of Chemistry, The University of Hong Kong, Pokfluam Road (Hong Kong); Yam, ChiYung [Department of Chemistry, The University of Hong Kong, Pokfluam Road (Hong Kong); Beijing Computational Science Research Center, Beijing 100094 (China)

    2015-09-14

    Recent development of theoretical method for dissipative quantum transport has achieved notable progresses in the weak or strong electron-phonon coupling regime. However, a generalized theory for dissipative quantum transport in a wide parameter space had not been established. In this work, a variational polaron theory for dissipative quantum transport in a wide range of electron-phonon coupling is developed. The optimal polaron transformation is determined by the optimization of the Feynman-Bogoliubov upper bound of free energy. The free energy minimization ends up with an optimal mean-field Hamiltonian and a minimal interaction Hamiltonian. Hence, second-order perturbation can be applied to the transformed system, resulting in an accurate and efficient method for the treatment of dissipative quantum transport with different electron-phonon coupling strength. Numerical benchmark calculation on a single site model coupled to one phonon mode is presented.

  11. Solute transport modeling using morphological parameters of step-pool reaches

    Science.gov (United States)

    JiméNez, Mario A.; Wohl, Ellen

    2013-03-01

    Step-pool systems have been widely studied during the past few years, resulting in enhanced knowledge of mechanisms for sediment transport, energy dissipation and patterns of self-organization. We use rhodamine tracer data collected in nine step-pool reaches during high, intermediate and low flows to explore scaling of solute transport processes. Using the scaling patterns found, we propose an extension of the Aggregated Dead Zone (ADZ) approach for solute transport modeling based on the morphological features of step-pool units and their corresponding inherent variability within a stream reach. In addition to discharge, the reach-average bankfull width, mean step height, and the ratio of pool length to step-to-step length can be used as explanatory variables for the dispersion process within the studied reaches. These variables appeared to be sufficient for estimating ADZ model parameters and simulating solute transport in predictive mode for applications in reaches lacking tracer data.

  12. A variational approach for dissipative quantum transport in a wide parameter space.

    Science.gov (United States)

    Zhang, Yu; Yam, ChiYung; Chen, GuanHua

    2015-09-14

    Recent development of theoretical method for dissipative quantum transport has achieved notable progresses in the weak or strong electron-phonon coupling regime. However, a generalized theory for dissipative quantum transport in a wide parameter space had not been established. In this work, a variational polaron theory for dissipative quantum transport in a wide range of electron-phonon coupling is developed. The optimal polaron transformation is determined by the optimization of the Feynman-Bogoliubov upper bound of free energy. The free energy minimization ends up with an optimal mean-field Hamiltonian and a minimal interaction Hamiltonian. Hence, second-order perturbation can be applied to the transformed system, resulting in an accurate and efficient method for the treatment of dissipative quantum transport with different electron-phonon coupling strength. Numerical benchmark calculation on a single site model coupled to one phonon mode is presented.

  13. Estimating flow and transport parameters in the unsaturated zone with pore water stable isotopes

    Directory of Open Access Journals (Sweden)

    M. Sprenger

    2014-10-01

    Full Text Available Determining the soil hydraulic properties is a prerequisite to physically model transient water flow and solute transport in the vadose zone. Estimating these properties by inverse modelling techniques has become more common within the last two decades. While these inverse approaches usually fit simulations to hydrometric data, we expanded the methodology by using independent information about the stable isotope composition of the soil pore water depth profile as a single or additional optimization target. To demonstrate the potential and limits of this approach, we compared the results of three inverse modelling strategies where the fitting targets were (a pore water isotope concentrations, (b a combination of pore water isotope concentrations and soil moisture time series, and (c a two-step approach using first soil moisture data to determine water flow parameters and then the pore water stable isotope concentrations to estimate the solute transport parameters. The analyses were conducted at three study sites with different soil properties and vegetation. The transient unsaturated water flow was simulated by numerically solving the Richards equation with the finite-element code of Hydrus-1D. The transport of deuterium was simulated with the advection-dispersion equation, and the Hydrus code was modified to allow for deuterium loss during evaporation. The Mualem–van Genuchten and the longitudinal dispersivity parameters were determined for two major soil horizons at each site. The results show that approach (a using only the pore water isotope content cannot substitute hydrometric information to derive parameter sets that reflect the observed soil moisture dynamics, but gives comparable results when the parameter space is constrained by pedotransfer functions. Approaches (b and (c using both, the isotope profiles and the soil moisture time series resulted in satisfying model performances and good parameter identifiability. However, approach

  14. Measurement of carrier transport and recombination parameter in heavily doped silicon

    Science.gov (United States)

    Swanson, Richard M.

    1986-01-01

    The minority carrier transport and recombination parameters in heavily doped bulk silicon were measured. Both Si:P and Si:B with bulk dopings from 10 to the 17th and 10 to the 20th power/cu cm were studied. It is shown that three parameters characterize transport in bulk heavily doped Si: the minority carrier lifetime tau, the minority carrier mobility mu, and the equilibrium minority carrier density of n sub 0 and p sub 0 (in p-type and n-type Si respectively.) However, dc current-voltage measurements can never measure all three of these parameters, and some ac or time-transient experiment is required to obtain the values of these parameters as a function of dopant density. Using both dc electrical measurements on bipolar transitors with heavily doped base regions and transients optical measurements on heavily doped bulk and epitaxially grown samples, lifetime, mobility, and bandgap narrowing were measured as a function of both p and n type dopant densities. Best fits of minority carrier mobility, bandgap narrowing and lifetime as a function of doping density (in the heavily doped range) were constructed to allow accurate modeling of minority carrier transport in heavily doped Si.

  15. Exchange processes at geosphere-biosphere interface. Current SKB approach and example of coupled hydrological-ecological approach

    Energy Technology Data Exchange (ETDEWEB)

    Woerman, Anders [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Biometry and Technology

    2003-09-01

    The design of the repository for final disposal of spent nuclear fuel proposed by SKB is based on a multi-barrier system, in which the geosphere and biosphere are the utmost barrier surrounding the engineer barriers. This report briefly reviews the current approach taken by SKB to account for hydrological and ecological processes at the geosphere-biosphere interface (GBI) and their future plans in this area. A simple analysis was performed to shift the focus of performance assessment involving geosphere-biosphere interface modelling from the very simplistic assumption that the quaternary sediments are bypassed to one in which a more detailed model for sub-surface flows is included. This study indicated that, for many assumed ecosystem descriptions, the presence of the GBI leads to lower maximum doses to individual humans compared to a case when the GBI is neglected. This effect is due to the additional 'barrier' offered by the GBI. The main exposure pathways were assumed to occur through the food web. However, particularly the leakage on land through the stream-network and lakes can lead to higher doses due to ecosystem interaction with arable land. A scenario that gives particularly long duration of doses occurs due to land rise and with the transformation of the former bay and lake bed sediments into agricultural land. This effect is due to the significant retention or accumulation in aquatic sediment, which causes high activities to build up with time. Particularly, in combination with changing conditions in climate, humans life-style or geographic conditions (land rise, deforestation,etc.) doses to individual humans can be large.

  16. Mechanistic interpretation of conventional Michaelis-Menten parameters in a transporter system.

    Science.gov (United States)

    Vivian, Diana; Polli, James E

    2014-11-20

    The aim was to elucidate how steps in drug translocation by a solute carrier transporter impact Michaelis-Menten parameters Km, Ki, and Vmax. The first objective was to derive a model for carrier-mediated substrate translocation and perform sensitivity analysis with regard to the impact of individual microrate constants on Km, Ki, and Vmax. The second objective was to compare underpinning microrate constants between compounds translocated by the same transporter. Equations for Km, Ki, and Vmax were derived from a six-state model involving unidirectional transporter flipping and reconfiguration. This unidirectional model is applicable to co-transporter type solute carriers, like the apical sodium-dependent bile acid transporter (ASBT) and the proton-coupled peptide cotransporter (PEPT1). Sensitivity analysis identified the microrate constants that impacted Km, Ki, and Vmax. Compound comparison using the six-state model employed regression to identify microrate constant values that can explain observed Km and Vmax values. Results yielded some expected findings, as well as some unanticipated effects of microrate constants on Km, Ki, and Vmax. Km and Ki were found to be equal for inhibitors that are also substrates. Additionally, microrate constant values for certain steps in transporter functioning influenced Km and Vmax to be low or high. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Numerical investigation of Scrape Off Layer anomalous particle transport for MAST parameters

    DEFF Research Database (Denmark)

    Militello, F.; Fundamenski, W.; Naulin, Volker

    2013-01-01

    Numerical simulations of L-mode plasma turbulence in the Scrape Off Layer of MAST are presented. Relevant features of the boundary plasma, such as the thickness of the density layer or the statistics of the fluctuations are related to the edge density and temperature, plasma current and parallel...... parameters and show a certain degree of universality. Effective transport coefficients are calculated for several plasma conditions and display a strong nonlinear dependence on the parameters and on the radial variable. Finally, it is shown how the perpendicular particle fluxes in the Scrape Off Layer...

  18. Electron transport parameters in CO$_2$: scanning drift tube measurements and kinetic computations

    CERN Document Server

    Vass, M; Loffhagen, D; Pinhao, N; Donko, Z

    2016-01-01

    This work presents transport coefficients of electrons (bulk drift velocity, longitudinal diffusion coefficient, and effective ionization frequency) in CO2 measured under time-of-flight conditions over a wide range of the reduced electric field, 15Td <= E/N <= 2660Td in a scanning drift tube apparatus. The data obtained in the experiments are also applied to determine the effective steady-state Townsend ionization coefficient. These parameters are compared to the results of previous experimental studies, as well as to results of various kinetic computations: solutions of the electron Boltzmann equation under different approximations (multiterm and density gradient expansions) and Monte Carlo simulations. The experimental data extend the range of E/N compared with previous measurements and are consistent with most of the transport parameters obtained in these earlier studies. The computational results point out the range of applicability of the respective approaches to determine the different measured tr...

  19. Sensitivity of benzene natural attenuation to variations in kinetic and transport parameters in Liwa Aquifer, UAE.

    Science.gov (United States)

    Mohamed, Mohamed M; Saleh, Nawal E; Sherif, Mohsen M

    2010-04-01

    Dissolved benzene was detected in the shallow unconfined Liwa aquifer (UAE). This aquifer represents the main freshwater source for a nearby residence camp area. A finite element model is used to simulate the fate, transport, and attenuation of the dissolved benzene plume to help decision makers assess natural attenuation as a viable remediation option. Sensitivity of benzene attenuation to uncertainties in the estimation of some of the kinetic and transport parameters is studied. It was found that natural attenuation is more sensitive to microbial growth rate and half saturation coefficients of both benzene and oxygen than initial biomass concentration and dispersivity coefficients. Increasing microbial growth rate by fourfold increased natural attenuation effectiveness after 40 years by 10%; while decreasing it by fourfold decreased natural attenuation effectiveness by 77%. On the other hand, increasing half saturation coefficient by fourfold decreased natural attenuation effectiveness by 46% in 40 years. Decreasing the same parameter fourfold caused natural attenuation effectiveness to increase by 9%.

  20. Correlating Gas Transport Parameters and X-ray Computed Tomography Measurements in Porous Media

    DEFF Research Database (Denmark)

    Naveed, Muhammad; Hamamoto, Shoichiro; Kawamoto, Ken

    2013-01-01

    -dried and partially saturated conditions. Gas transport parameters including gas dispersivity (α), diffusivity (DP/D0), and permeability (ka) were measured using a unified measurement system (UMS). The 3DMA-Rock computational package was used for analysis of three-dimensional CT data. A strong linear relationship...... was found between α and tortuosity calculated from gas transport parameters (Equation (Uncited) Image Tools), indicating that gas dispersivity has a linear and inverse relationship with gas diffusivity. A linear relationship was also found between ka and d50/TUMS2, indicating a strong dependency of ka...... on mean particle size and direct correlation with gas diffusivity. Tortuosity (TMFX) and equivalent pore diameter (deq.MFX) analyzed from microfocus X-ray CT increased linearly with increasing d50 for both Granusil and Accusand and further showing no effect of particle shape. The TUMS values showed...

  1. Colloid facilitated transport in fractured rocks : parameter estimation and comparison with experimental data.

    Energy Technology Data Exchange (ETDEWEB)

    Viswanathan, H. S. (Hari Selvi); Wolfsberg, A. V. (Andrew V.); Reimus, P. W. (Paul William); Ware, S. D. (Stuart D.); Lu, G. (Guoping)

    2003-01-01

    Colloid-facilitated migration of plutonium in fractured rock has been implicated in both field and laboratory studies . Other reactive radionuclides may also experience enhanced mobility due to groundwater colloids. Model prediction of this process is necessary for assessment of contaminant boundaries in systems for which radionuclides are already in the groundwater and for performance assessment of potential repositories for radioactive waste. Therefore, a reactive transport model is developed and parameterized using results from controlled laboratory fracture column experiments. Silica, montmorillonite and clinoptilolite colloids are used in the experiments along with plutonium and Tritium . . The goal of the numerical model is to identify and parameterize the physical and chemical processes that affect the colloid-facilitated transport of plutonium in the fractures. The parameters used in this model are similar in form to those that might be used in a field-scale transport model.

  2. Field scale variability of solute transport parameters and related soil properties

    Directory of Open Access Journals (Sweden)

    B. Lennartz

    1997-01-01

    Full Text Available The spatial variability of transport parameters has to be taken into account for a reliable assessment of solute behaviour in natural field soils. Two field sites were studied by collecting 24 and 36 small undisturbed soil columns at an uniform grid of 15 m spacing. Displacement experiments were conducted in these columns with bromide traced water under unsaturated steady state transport conditions. Measured breakthrough curves (BTCs were evaluated with the simple convective-dispersive equation (CDE. The solute mobility index (MI calculated as the ratio of measured to fitted pore water velocity and the dispersion coefficient (D were used to classify bromide breakthrough behaviour. Experimental BTCs were classified into two groups: type I curves expressed classical solute behaviour while type II curves were characterised by the occurrence of a bromide concentration maximum before 0.35 pore volumes of effluent (MI<0.35 resulting from preferential flow conditions. Six columns from site A and 8 from site B were identified as preferential. Frequency distributions of the transport parameters (MI and D of both sites were either extremely skewed or bimodal. Log-transformation did not lead to a normal distribution in any case. Contour maps of bromide mass flux at certain time steps indicated the clustering of preferential flow regions at both sites. Differences in the extent of preferential flow between sites seemed to be governed by soil structure. Linear cross correlations among transport parameters and independently measured soil properties revealed relations between solute mobility and volumetric soil water content at time of sampling, texture and organic carbon content. The volumetric field soil water content, a simple measure characterising the soil hydraulic behaviour at the sampling location, was found to be a highly sensitive parameter with respect to solute mobility and preferential flow situations. Almost no relation was found between solute

  3. Difference Tracker: ImageJ plugins for fully automated analysis of multiple axonal transport parameters.

    Science.gov (United States)

    Andrews, Simon; Gilley, Jonathan; Coleman, Michael P

    2010-11-30

    Studies of axonal transport are critical, not only to understand its normal regulation, but also to determine the roles of transport impairment in disease. Exciting new resources have recently become available allowing live imaging of axonal transport in physiologically relevant settings, such as mammalian nerves. Thus the effects of disease, ageing and therapies can now be assessed directly in nervous system tissue. However, these imaging studies present new challenges. Manual or semi-automated analysis of the range of transport parameters required for a suitably complete evaluation is very time-consuming and can be subjective due to the complexity of the particle movements in axons in ex vivo explants or in vivo. We have developed Difference Tracker, a program combining two new plugins for the ImageJ image-analysis freeware, to provide fast, fully automated and objective analysis of a number of relevant measures of trafficking of fluorescently labeled particles so that axonal transport in different situations can be easily compared. We confirm that Difference Tracker can accurately track moving particles in highly simplified, artificial simulations. It can also identify and track multiple motile fluorescently labeled mitochondria simultaneously in time-lapse image stacks from live imaging of tibial nerve axons, reporting values for a number of parameters that are comparable to those obtained through manual analysis of the same axons. Difference Tracker therefore represents a useful free resource for the comparative analysis of axonal transport under different conditions, and could potentially be used and developed further in many other studies requiring quantification of particle movements.

  4. Electron Transport Parameters Study for Transition Metal-Doped Armchair Graphene Nanoribbon via Acoustical Phonon Interactions

    Science.gov (United States)

    Pandya, Ankur; Jha, Prafulla K.

    2017-04-01

    Electron transport parameters such as electron effective mass, Fermi velocity of an electron and electron mobility are calculated for transition metal [manganese (Mn), cobalt (Co)]-doped armchair graphene nanoribbon (aGNR) via polar acoustical phonon [piezoelectric (PZ)] scattering and acoustical deformation potential (ADP) scattering under a high electric field and different doping concentrations. Moreover, the effect of dopant site on these electron transport parameters is also investigated. It is observed that the electron effective mass is reduced significantly in doped aGNR in comparison to pure GNR. It is observed that the net electron mobility contributed by both ADP and PZ mechanisms for Mn-doped aGNR as well as Co-doped aGNR varies in similar fashion as semiconductors wherein the net electron mobility (ADP + PZ) for Mn-doped aGNR is greater than that for the Co-doped graphene nanoribbon. Moreover, it is found that there is no impact of variation in dopant site on the electron transport parameters considered in this study.

  5. Effect of transport-pathway simplifications on projected releases of radionuclides from a nuclear waste repository (Sweden)

    Science.gov (United States)

    Selroos, Jan-Olof; Painter, Scott L.

    2012-12-01

    The Swedish Nuclear Fuel and Waste Management Company has recently submitted an application for a license to construct a final repository for spent nuclear fuel, at approximately 500 m depth in crystalline bedrock. Migration pathways through the geosphere barrier are geometrically complex, with segments in fractured rock, deformation zones, backfilled tunnels, and near-surface soils. Several simplifications of these complex migration pathways were used in the assessments of repository performance that supported the license application. Specifically, in the geosphere transport calculations, radionuclide transport in soils and tunnels was neglected, and deformation zones were assumed to have transport characteristics of fractured rock. The effects of these simplifications on the projected performance of the geosphere barrier system are addressed. Geosphere performance is shown to be sensitive to how transport characteristics of deformation zones are conceptualized and incorporated into the model. Incorporation of advective groundwater travel time within backfilled tunnels reduces radiological dose from non-sorbing radionuclides such as I-129, while sorption in near-surface soils reduces radiological doses from sorbing radionuclides such as Ra-226. These results help quantify the degree to which geosphere performance was pessimistically assessed, and provide some guidance on how future studies to reduce uncertainty in geosphere performance may be focused.

  6. Soil transport parameters of potassium under a tropical saline soil condition using STANMOD

    Science.gov (United States)

    Suzanye da Silva Santos, Rafaelly; Honorio de Miranda, Jarbas; Previatello da Silva, Livia

    2015-04-01

    Environmental responsibility and concerning about the final destination of solutes in soil, so more studies allow a better understanding about the solutes behaviour in soil. Potassium is a macronutrient that is required in high concentrations, been an extremely important nutrient for all agricultural crops. It plays essential roles in physiological processes vital for plant growth, from protein synthesis to maintenance of plant water balance, and is available to plants dissolved in soil water while exchangeable K is loosely held on the exchange sites on the surface of clay particles. K will tend to be adsorbed onto the surface of negatively charged soil particles. Potassium uptake is vital for plant growth but in saline soils sodium competes with potassium for uptake across the plasma membrane of plant cells. This can result in high Na+:K+ ratios that reduce plant growth and eventually become toxic. This study aimed to obtain soil transport parameters of potassium in saline soil, such as: pore water velocity in soil (v), retardation factor (R), dispersivity (λ) and dispersion coefficient (D), in a disturbed sandy soil with different concentrations of potassium chlorate solution (KCl), which is one of the most common form of potassium fertilizer. The experiment was carried out using soil samples collected in a depth of 0 to 20 cm, applying potassium chlorate solution containing 28.6, 100, 200 and 500 mg L-1 of K. To obtain transport parameters, the data were adjusted with the software STANMOD. At low concentrations, interaction between potassium and soil occur more efficiently. It was observed that only the breakthrough curve prepared with solution of 500 mg L-1 reached the applied concentration, and the solution of 28.6 mg L-1 overestimated the parameters values. The STANMOD proved to be efficient in obtaining potassium transport parameters; KCl solution to be applied should be greater than 500 mg L-1; solutions with low concentrations tend to overestimate

  7. Multiphase flow in the geosphere around a repository for spent nuclear fuels. Inventory of the present knowledge; Flerfasfloede i geosfaeren kring ett foervar foer utbraent kaernbraensle. Inventering av kunskapslaeget

    Energy Technology Data Exchange (ETDEWEB)

    Aalen, Bengt [Bergab, Goeteborg (Sweden)

    2004-10-01

    Important quantities of gas can form in an underground repository for nuclear wastes. Gas can be formed through: corroding metals; water and certain organic substances that undergo radiolysis; organic material degrading through microbial activity. The last point is of concern mainly for intermediate-level wastes, which can hold large amounts of organic materials. The first point is the main process for high-level wastes. The gas could transport radioactive substances through the buffer and the geosphere into the biosphere, or affect the performance of the repository in a negative way. The present report gives a review of the knowledge about two-phase flow in connection with deep geologic repositories for spent nuclear fuel.

  8. Using data from colloid transport experiments to parameterize filtration model parameters for favorable conditions

    Science.gov (United States)

    Kamai, Tamir; Nassar, Mohamed K.; Nelson, Kirk E.; Ginn, Timothy R.

    2017-04-01

    Colloid filtration in porous media spans across many disciplines and includes scenarios such as in-situ bioremediation, colloid-facilitated transport, water treatment of suspended particles and pathogenic bacteria, and transport of natural and engineered nanoparticles in the environment. Transport and deposition of colloid particles in porous media are determined by a combination of complex processes and forces. Given the convoluted physical, chemical, and biological processes involved, and the complexity of porous media in natural settings, it should not come as surprise that colloid filtration theory does not always sufficiently predict colloidal transport, and that there is still a pressing need for improved predictive capabilities. Here, instead of developing the macroscopic equation from pore-scale models, we parametrize the different terms in the macroscopic collection equation through fitting it to experimental data, by optimizing the parameters in the different terms of the equation. This way we combine a mechanistically-based filtration-equation with empirical evidence. The impact of different properties of colloids and porous media are studied by comparing experimental properties with different terms of the correlation equation. This comparison enables insight about different processes that occur during colloid transport and retention under in porous media under favorable conditions, and provides directions for future theoretical developments.

  9. Integrated Hydrogeophysical and Hydrogeologic Driven Parameter Upscaling for Dual-Domain Transport Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Gregory Flach; Mary Harris; Susan Hubbard; Camelia Knapp; Mike Kowalsky; Maggie Millings; John Shafer; Mike Waddell

    2006-06-01

    Our research project is motivated by the observations that conventional characterization approaches capture only a fraction of heterogeneity affecting field-scale transport, and that conventional modeling approaches, which use this sparse data, typically do not successfully predict long term plume behavior with sufficient accuracy to guide remedial strategies. Our working hypotheses are that improved prediction of contaminant transport can be achieved using a dual-domain transport approach and field-scale characterization approaches. Our overall objectives are to: (1) develop a dual-domain modeling approach using the TOUGH2 family of codes that incorporates the key interactions between mobile and immobile transport regions that are expected to play a role in long term plume behavior; (2) develop a facies-based multi-scale characterization approach that utilizes log, crosshole, and surface-based characterization information and that is guided by the parameterization needs of the dual domain modeling; and (3) evaluate the approaches by applying them to the prediction of plume behavior at the P-Area at the Savannah River Site (Figure 1). Our three-year project scope includes development of multi-scale characterization and dual-domain modeling approach and field-scale data acquisition (Year 1); Numerical simulations and field-scale characterization (Year 2); and Plume transport simulations and exploration of optimal dual-domain parameters (Year 3).

  10. Effect of counter- and co-ions on the structural transport parameters of sulfoacid cationite membranes

    Science.gov (United States)

    Demina, O. A.; Falina, I. V.; Kononenko, N. A.; Demin, A. V.

    2016-08-01

    The diffusion permeability and specific electroconductivity of MK-40 sulfoacid cationite and Nafion 425 membranes are studied experimentally in NaOH, NaCl, and HCl solutions with various concentrations. The resulting concentration dependences of the electrodiffusion characteristics and data on the nonexchange sorption of the electrolytes are used to calculate the structural transport parameters of the membranes in terms of a two-phase conduction model. Analysis of a set of parameters, including the electroconductivity and diffusion permeability of the membrane gel phase, the volume fractions of the conductive phases, and a parameter that reflects their relative positions, the Donnan constant, and the diffusion coefficients of counter and co-ions in the membrane gel phase reveals the effect the nature of counter- and co-ions has on the electrodiffusion, structural, and sorption characteristics of sulfoacid cationite membranes with different types of structure.

  11. Data preprocessing for parameter estimation. An application to a reactive bimolecular transport model

    CERN Document Server

    Cuch, Daniel A; Hasi, Claudio D El

    2015-01-01

    In this work we are concerned with the inverse problem of the estimation of modeling parameters for a reactive bimolecular transport based on experimental data that is non-uniformly distributed along the interval where the process takes place. We proposed a methodology that can help to determine the intervals where most of the data should be taken in order to obtain a good estimation of the parameters. For the purpose of reducing the cost of laboratory experiments, we propose to simulate data where is needed and it is not available, a PreProcesing Data Fitting (PPDF).We applied this strategy on the estimation of parameters for an advection-diffusion-reaction problem in a porous media. Each step is explained in detail and simulation results are shown and compared with previous ones.

  12. Numerical investigation of Scrape Off Layer anomalous particle transport for MAST parameters

    CERN Document Server

    Militello, F; Naulin, V; Nielsen, A H

    2013-01-01

    Numerical simulations of L-mode plasma turbulence in the Scrape Off Layer of MAST are presented. Relevant features of the boundary plasma, such as the thickness of the density layer or the statistics of the fluctuations are related to the edge density and temperature, plasma current and parallel connection length. It is found that the density profile is weakly affected by the edge density, it broadens when the current or the temperature are decreased while the connection length has the opposite effect. The statistics of the turbulence is relatively insensitive to variations of all the edge parameters and show a certain degree of universality. Effective transport coefficients are calculated for several plasma conditions and display a strong nonlinear dependence on the parameters and on the radial variable. Finally, it is shown how the perpendicular particle fluxes in the Scrape Off Layer are related to the edge parameters.

  13. Review and analysis of parameters for assessing transport of environmentally released radionuclides through agriculture

    Energy Technology Data Exchange (ETDEWEB)

    Baes, C.F. III; Sharp, R.D.; Sjoreen, A.L.; Shor, R.W.

    1984-09-01

    Most of the default parameters incorporated into the TERRA computer code are documented including a literature review and systematic analysis of element-specific transfer parameters B/sub v/, B/sub r/, F/sub m/, F/sub f/, and K/sub d/. This review and analysis suggests default values which are consistent with the modeling approaches taken in TERRA and may be acceptable for most assessment applications of the computer code. However, particular applications of the code and additional analysis of elemental transport may require alternative default values. Use of the values reported herein in other computer codes simulating terrestrial transport is not advised without careful interpretation of the limitations and scope these analyses. An approach to determination of vegetation-specific interception fractions is also discussed. The limitations of this approach are many, and its use indicates the need for analysis of deposition, interception, and weathering processes. Judgement must be exercised in interpretation of plant surface concentrations generated. Finally, the location-specific agricultural, climatological, and population parameters in the default SITE data base documented. These parameters are intended as alternatives to average values currently used. Indeed, areas in the United States where intensive crop, milk, or beef production occurs will be reflected in the parameter values as will areas where little agricultural activity occurs. However, the original information sources contained some small error and the interpolation and conversion methods used will add more. Parameters used in TERRA not discussed herein are discussed in the companion report to this one - ORNL-5785. In the companion report the models employed in and the coding of TERRA are discussed. These reports together provide documentation of the TERRA code and its use in assessments. 96 references, 78 figures, 21 tables.

  14. MATER - Pianeta Terra-Mare: an interactive and multidisciplinary approach to Geosphere sciences

    Science.gov (United States)

    Piangiamore, Giovanna Lucia; Fanelli, Emanuela; Furia, Stefania; Garau, Daniela; Merlino, Silvia; Musacchio, Gemma; Carla Centineo, Maria

    2016-04-01

    hydro-geological risk and climate change targeted to students from 8 to 14 years; Planet Sea was articulated in a series of laboratories on the physical-chemical properties ("a sustaining sea") and of the bio-ecological aspects ("a sea of resources") of the sea, engaging students from 4 to 14 years. Scientific conferences, targeted from teenagers and up and open to public, have been organized during the opening and closing weeks of the project, inside the "Week of Planet Earth" 2014 and 2015. The project was also a "peer-education experiment", where students of the High School "Pacinotti" (La Spezia) and of "ISA 10" (Lerici) and "ISA 2" (La Spezia) have played the role of guides in the interactive paths. MATER has reached ca. 1000 students and had excellent feedbacks from teachers and students, supported by questionnaires and press releases. Through the dedicated website, MATER is expected to reach a broader scholastic community, outside its local context. The project was a good example of cooperation of different territorial institutions/associations, working together to promote the culture of prevention and sustainability, involving future citizens to reflect on the values of appropriate behaviors and best practices towards an ethical and sustainable interaction between human activities with the geosphere.

  15. Validating Mechanistic Sorption Model Parameters and Processes for Reactive Transport in Alluvium

    Energy Technology Data Exchange (ETDEWEB)

    Zavarin, M; Roberts, S K; Rose, T P; Phinney, D L

    2002-05-02

    The laboratory batch and flow-through experiments presented in this report provide a basis for validating the mechanistic surface complexation and ion exchange model we use in our hydrologic source term (HST) simulations. Batch sorption experiments were used to examine the effect of solution composition on sorption. Flow-through experiments provided for an analysis of the transport behavior of sorbing elements and tracers which includes dispersion and fluid accessibility effects. Analysis of downstream flow-through column fluids allowed for evaluation of weakly-sorbing element transport. Secondary Ion Mass Spectrometry (SIMS) analysis of the core after completion of the flow-through experiments permitted the evaluation of transport of strongly sorbing elements. A comparison between these data and model predictions provides additional constraints to our model and improves our confidence in near-field HST model parameters. In general, cesium, strontium, samarium, europium, neptunium, and uranium behavior could be accurately predicted using our mechanistic approach but only after some adjustment was made to the model parameters. The required adjustments included a reduction in strontium affinity for smectite, an increase in cesium affinity for smectite and illite, a reduction in iron oxide and calcite reactive surface area, and a change in clinoptilolite reaction constants to reflect a more recently published set of data. In general, these adjustments are justifiable because they fall within a range consistent with our understanding of the parameter uncertainties. These modeling results suggest that the uncertainty in the sorption model parameters must be accounted for to validate the mechanistic approach. The uncertainties in predicting the sorptive behavior of U-1a and UE-5n alluvium also suggest that these uncertainties must be propagated to nearfield HST and large-scale corrective action unit (CAU) models.

  16. Estimating flow and transport parameters in the unsaturated zone with pore water stable isotopes

    Science.gov (United States)

    Sprenger, M.; Volkmann, T. H. M.; Blume, T.; Weiler, M.

    2015-06-01

    Determining the soil hydraulic properties is a prerequisite to physically model transient water flow and solute transport in the vadose zone. Estimating these properties by inverse modelling techniques has become more common within the last 2 decades. While these inverse approaches usually fit simulations to hydrometric data, we expanded the methodology by using independent information about the stable isotope composition of the soil pore water depth profile as a single or additional optimization target. To demonstrate the potential and limits of this approach, we compared the results of three inverse modelling strategies where the fitting targets were (a) pore water isotope concentrations, (b) a combination of pore water isotope concentrations and soil moisture time series, and (c) a two-step approach using first soil moisture data to determine water flow parameters and then the pore water stable isotope concentrations to estimate the solute transport parameters. The analyses were conducted at three study sites with different soil properties and vegetation. The transient unsaturated water flow was simulated by solving the Richards equation numerically with the finite-element code of HYDRUS-1D. The transport of deuterium was simulated with the advection-dispersion equation, and a modified version of HYDRUS was used, allowing deuterium loss during evaporation. The Mualem-van Genuchten and the longitudinal dispersivity parameters were determined for two major soil horizons at each site. The results show that approach (a), using only the pore water isotope content, cannot substitute hydrometric information to derive parameter sets that reflect the observed soil moisture dynamics but gives comparable results when the parameter space is constrained by pedotransfer functions. Approaches (b) and (c), using both the isotope profiles and the soil moisture time series, resulted in good simulation results with regard to the Kling-Gupta efficiency and good parameter

  17. Transport parameters of thin, supported cathode layers in solid oxide fuel cells (SOFCs); Transportparameter duenner, getraegerter Kathodenschichten der oxidkeramischen Brennstoffzelle

    Energy Technology Data Exchange (ETDEWEB)

    Wedershoven, Christian

    2010-12-22

    The aim of this work was to determine the transport properties of thin cathode layers, which are part of the composite layer of a fabricated anode-supported solid oxide fuel cell (SOFC). The transport properties of the anode and cathode have a significant influence on the electrochemical performance of a fuel cell stack and therefore represent an important parameter when designing fuel cell stacks. In order to determine the transport parameters of the cathode layers in a fabricated SOFC, it is necessary to permeate the thin cathode layer deposited on the gas-tight electrolyte with a defined gas transport. These thin cathode layers cannot be fabricated as mechanically stable single layers and cannot therefore be investigated in the diffusion and permeation experiments usually used to determine transport parameters. The setup of these experiments - particularly the sample holder - was therefore altered in this work. The result of this altered setup was a three-dimensional flow configuration. Compared to the conventional setup, it was no longer possible to describe the gas transport in the experiments with an analytical one-dimensional solution. A numerical solution process had to be used to evaluate the measurements. The new setup permitted a sufficiently symmetrical gas distribution and thus allowed the description of the transport to be reduced to a two-dimensional description, which significantly reduced the computational effort required to evaluate the measurements. For pressure-induced transport, a parametrized coherent expression of transport could be derived. This expression is equivalent to the analytical description of the transport in conventional measurement setups, with the exception of parameters that describe the geometry of the gas diffusion. In this case, a numerical process is not necessary for the evaluation. Using the transport parameters of mechanically stable anode substrates, which can be measured both in the old and the new setups, the old and

  18. Charcoal Morphometry for Paleoecological Analysis: The Effects of Fuel Type and Transportation on Morphological Parameters

    Directory of Open Access Journals (Sweden)

    Alastair J. Crawford

    2014-08-01

    Full Text Available Premise of the study: Charcoal particles preserved in sediments are used as indicators of paleowildfire. Most research focuses on abundance as an indicator of fire frequency, but charcoals also convey information about the vegetation from which they are derived. One potential source of information is their morphology, which is influenced by the parent material, the nature of the fire, and subsequent transportation and burial. Methods: We charcoalified 26 materials from a range of plant taxa, and subjected them to simulated fluvial transport by tumbling them with water and gravel. We photographed the resulting particles, and used image analysis software to measure morphological parameters. Results: Leaf charcoal displayed a logarithmic decrease in area, and a logarithmic increase in circularity, with transportation time. Trends were less clear for stem or wood charcoal. Grass charcoal displayed significantly higher aspect ratios than other charcoal types. Conclusions: Leaf charcoal displays more easily definable relationships between morphological parameters and degree of breakdown than stem or wood charcoal. The aspect ratios of fossil mesocharcoal can indicate the broad botanical source of an assemblage. Coupled to estimates of charcoal abundance, this will improve understanding of the variation in flammability of ancient ecosystems.

  19. Uncertainty in the relationship between flow and parameters in models of pollutant transport

    Science.gov (United States)

    Romanowicz, R.; Osuch, M.; Wallis, S.; Napiórkowski, J. J.

    2009-04-01

    Fluorescent dye-tracer studies are usually performed under steady-state flow conditions. However, the model parameters, estimated using the tracer data, depend on the discharges. This paper investigates uncertainties in the relationship between discharges and parameters of a transient storage (TS) and an aggregated dead zone (ADZ) models. We apply a Bayesian statistical approach to derive the cumulative distribution of a range of model parameters conditioned on discharges. The data consist of eighteen tracer concentration profiles taken at different flow values at two cross-sections from the Murray Burn, a stream flowing through the Heriot-Watt University Campus at Riccarton in Edinburgh, Scotland. A number of studies have been reported of the dependence of TS and ADZ model parameters on discharge but there are very few studies on the uncertainty related to that parameterization, which is the aim of this work. As the TS model is purely deterministic and the ADZ model is stochastic, different approaches are required to estimate the uncertainty in the dependence of their parameters on flow. The Generalised Likelihood Uncertainty Estimation (GLUE) approach is suitable for the deterministic models and is therefore applied to the TS model. The method applies Monte Carlo sampling of parameter space used in multiple simulations of a deterministic transient storage model. The relationship between model parameters and flow has the form of a nonlinear regression model based on multiple random realizations of the deterministic transport model. The parameterization of that relationship and its introduction into the TS model allow for the conditioning of parameter estimates and as a result, also model predictions on the whole set of available observations. In the case of the ADZ model, the approach is based on Monte Carlo sampling of ADZ model parameters, taking into account heteroscedastic variance of the observations and estimates of the covariance of the model parameters

  20. Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nye County, Nevada, Revision 0

    Energy Technology Data Exchange (ETDEWEB)

    Drici, Warda

    2003-08-01

    This report documents the analysis of the available transport parameter data conducted in support of the development of a Corrective Action Unit (CAU) groundwater flow model for Central and Western Pahute Mesa: CAUs 101 and 102.

  1. Bulk matter evolution and extraction of jet transport parameter in heavy-ion collisions at RHIC

    CERN Document Server

    Chen, Xiao-Fang; Wang, Enke; Wang, Xin-Nian; Xu, Zhe

    2010-01-01

    Within the picture of jet quenching induced by multiple parton scattering and gluon bremsstrahlung, medium modification of parton fragmentation functions and therefore the suppression of large transverse momentum hadron spectra are controlled by both the value and the space-time profile of the jet transport parameter along the jet propagation path. Experimental data on single hadron suppression in high-energy heavy-ion collisions at the RHIC energy are analyzed within the higher-twist (HT) approach to the medium modified fragmentation functions and the next-to-leading order (NLO) perturbative QCD (pQCD) parton model. Assuming that the jet transport parameter $\\hat q$ is proportional to the particle number density in both QGP and hadronic phase, experimental data on jet quenching in deeply inelastic scattering (DIS) off nuclear targets can provide guidance on $\\hat q_{h}$ in the hot hadronic matter. One can then study the dependence of extracted initial value of jet quenching parameter $\\hat q_{0}$ at initial ...

  2. Relationship Between Cerebral Oxygenation and Hemodynamic and Oxygen Transport Parameters in Surgery for Acquired Heart Diseases

    Directory of Open Access Journals (Sweden)

    A. I. Lenkin

    2012-01-01

    Full Text Available Objective: to evaluate the relationship between cerebral oxygenation and hemodynamic and oxygen transport parameters in surgical correction of concomitant acquired heart diseases. Subjects and methods. Informed consent was received from 40 patients who required surgery because of concomitant (two or more acquired heart defects. During procedure, perioperative monitoring of oxygen transport and cerebral oxygenation was performed with the aid of PiCCO2 monitor (Pulsion Medical Systems, Germany and a Fore-Sight cerebral oximeter (CASMED, USA. Anesthesia was maintained with propofol and fen-tanyl, by monitoring the depth of anesthesia. Early postoperative intensive therapy was based on the protocol for early targeted correction of hemodynamic disorders. Oxygen transport and cerebral oxygenation parameters were estimated intraopera-tively and within 24 postoperative hours. A statistical analysis including evaluation of Spearman correlations was performed with the aid of SPSS 15.0. Results. During perfusion, there was a relationship between cerebral oximetry values and hemat-ocrit levels, and oxygen partial pressure in the venous blood. Furthermore, a negative correlation between cerebral oximetry values and blood lactate levels was found 30 minutes after initiation of extracorporeal circulation (EC. During the study, there was a positive correlation between cerebral oxygenation and values of cardiac index, central venous saturation, and oxygen delivery index. There was a negative relationship between cerebral oxygenation and extravascular lung water at the beginning of surgery and a correlation between cerebral oximetry values and oxygenation index by the end of the first 24 postoperative hours. Conclusion. The cerebral oxygenation values correlate -with the main determinants of oxygen transport during EC and after cardiac surgical procedures. Cerebral oximetry may be used in early targeted therapy for the surgical correction of acquired combined

  3. A new methodology for determination of macroscopic transport parameters in drying porous media

    Science.gov (United States)

    Attari Moghaddam, A.; Kharaghani, A.; Tsotsas, E.; Prat, M.

    2015-12-01

    Two main approaches have been used to model the drying process: The first approach considers the partially saturated porous medium as a continuum and partial differential equations are used to describe the mass, momentum and energy balances of the fluid phases. The continuum-scale models (CM) obtained by this approach involve constitutive laws which require effective material properties, such as the diffusivity, permeability, and thermal conductivity which are often determined by experiments. The second approach considers the material at the pore scale, where the void space is represented by a network of pores (PN). Micro- or nanofluidics models used in each pore give rise to a large system of ordinary differential equations with degrees of freedom at each node of the pore network. In this work, the moisture transport coefficient (D), the pseudo desorption isotherm inside the network and at the evaporative surface are estimated from the post-processing of the three-dimensional pore network drying simulations for fifteen realizations of the pore space geometry from a given probability distribution. A slice sampling method is used in order to extract these parameters from PN simulations. The moisture transport coefficient obtained in this way is shown in Fig. 1a. The minimum of average D values demonstrates the transition between liquid dominated moisture transport region and vapor dominated moisture transport region; a similar behavior has been observed in previous experimental findings. A function is fitted to the average D values and then is fed into the non-linear moisture diffusion equation. The saturation profiles obtained from PN and CM simulations are shown in Fig. 1b. Figure 1: (a) extracted moisture transport coefficient during drying for fifteen realizations of the pore network, (b) average moisture profiles during drying obtained from PN and CM simulations.

  4. Quantum transport and two-parameter scaling at the surface of a weak topological insulator.

    Science.gov (United States)

    Mong, Roger S K; Bardarson, Jens H; Moore, Joel E

    2012-02-17

    Weak topological insulators have an even number of Dirac cones in their surface spectrum and are thought to be unstable to disorder, which leads to an insulating surface. Here we argue that the presence of disorder alone will not localize the surface states; rather, the presence of a time-reversal symmetric mass term is required for localization. Through numerical simulations, we show that in the absence of the mass term the surface always flow to a stable metallic phase and the conductivity obeys a one-parameter scaling relation, just as in the case of a strong topological insulator surface. With the inclusion of the mass, the transport properties of the surface of a weak topological insulator follow a two-parameter scaling form.

  5. Software package r{sup 3}t. Model for transport and retention in porous media. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Fein, E. (ed.)

    2004-07-01

    In long-termsafety analyses for final repositories for hazardous wastes in deep geological formations the impact to the biosphere due to potential release of hazardous materials is assessed for relevant scenarios. The model for migration of wastes from repositories to men is divided into three almost independent parts: the near field, the geosphere, and the biosphere. With the development of r{sup 3}t the feasibility to model the pollutant transport through the geosphere for porous or equivalent porous media in large, three-dimensional, and complex regions is established. Furthermore one has at present the ability to consider all relevant retention and interaction effects which are important for long-term safety analyses. These are equilibrium sorption, kinetically controlled sorption, diffusion into immobile pore waters, and precipitation. The processes of complexing, colloidal transport and matrix diffusion may be considered at least approximately by skilful choice of parameters. Speciation is not part of the very recently developed computer code r{sup 3}t. With r{sup 3}t it is possible to assess the potential dilution and the barrier impact of the overburden close to reality.

  6. Fortification of Transport Layer Security Protocol with Hashed Fingerprint Identity Parameter

    Directory of Open Access Journals (Sweden)

    Kuljeet Kaur

    2012-03-01

    Full Text Available Identity over the public links becomes quiet complex as Client and Server needs proper access rights with authentication. For determining clients identity with password Secured Shell Protocol or Public Key Infrastructure is deployed by various organizations. For end to end transport security SSL (Secured Socket Layer is the de facto standard having Record and Handshake protocol dealing with data integrity and data security respectively. It seems secure but many risks lurk in its use. So focus of the paper would be formulating the steps to be used for the enhancement of SSL. One more tier of security to the transport layer security protocol is added in this research paper by using fingerprints for identity authentication along with password for enhancement of SSL. Bio Hashing which will be done with the help of Minutiae Points at the fingerprints would be used for mutual authentication. New hash algorithm RNA-FINNT is generated in this research paper for converting minutiae points into hashed code. Value of hashed code would be stored at the Database in the Multi Server environment of an organization. Research paper will perform mutual authentication in the multi server environment of an organization with the use of fingerprint and password both as identity authentication parameters. This will strengthen record and handshake protocol which will enhance SSL and further enhancement of SSL will result in the fortification of Transport Layer Security Protocol.

  7. Determining fate and transport parameters for nitroglycerine, 2,4-dinitrotoluine, and nitroguanidine in soils

    Science.gov (United States)

    Gosch, D. L.; Dontsova, K.; Chorover, J.; Ferré, T.; Taylor, S.

    2010-12-01

    During military operations, a small fraction of propellant mass is not consumed during firing and is deposited onto the ground surface (Jenkins et al., 2006). Soluble propellant constituents can be released from particulate residues into the environment. Propellant constituents of interest for this study are nitroglycerine (NG), 2,4-dinitrotoluine (2,4-DNT), 2,6-dinitrotoluine (2,6-DNT), and nitroguanidine (NQ). The goal of this work is to determine fate and transport parameters for these constituents in three soils that represent a range of geographic locations and soil properties. This supports a companion study that looks at dissolution of NG, 2,4-DNT, 2,6-DNT, and NQ from fired and unfired solid propellant formulations and their transport in soils. The three soils selected for the study are Catlin silt loam (fine-silty, mixed, mesic, superactive Oxyaquic Argiudoll), Plymouth sandy loam (mesic, coated Typic Quartzipsamment), and Sassafras loam (fine loamy, siliceous, mesic Typic Hapudult). Two of these soils, Plymouth sandy loam and Sassafras loam, were collected on military installations. Linear adsorption coefficients and transformation rates of propellant constituents were determined in batch kinetic experiments. Soils were mixed with propellant constituent solutions (2 mg L-1) at 4:1 solution/soil mass ratio and equilibrated for 0, 1, 2, 6, 12, 24, 48, and 120 hr at which time samples were centrifuged and supernatant solutions were analyzed for target compounds by high performance liquid chromatography (HPLC) using U.S. EPA Method 8330b for NG, 2,4-DNT, and 2,6-DNT, and Walsh (1989) method for NQ. Adsorption and transformation of propellant constituents were determined from the decrease in solution concentration of these compounds. It was determined that all studied compounds were subjected to sorption by the solid phase and degradation. Catlin soil, with finer texture and high organic matter content, influenced solution concentration of NG, 2,4-DNT, 2,6-DNT

  8. Gas Transport Parameters for Landfill Final Cover Soil: Measurements and Model Modification by Dry Bulk Density

    Science.gov (United States)

    Wickramarachchi, P. N.; Kawamoto, K.; Hamamoto, S.; Nagamori, M.; Moldrup, P.; Komatsu, T.

    2011-12-01

    Landfill sites have been emerging in greenhouse warming scenarios as a significant source of atmospheric methane (CH4). Until recently, landfill management strategies have mainly addressed the problem of preventing groundwater contamination and reduction of leachate generation. Being one of the largest sources of anthropogenic CH4 emission, the final cover system should also be designed for minimizing the greenhouse gases migration into the atmosphere or the areas surrounding the landfill while securing the hydraulic performance. Compared to the intensive research efforts on hydraulic performances of landfill final cover soil, few studies about gas transport characteristics of landfill cover soils have been done. However, recent soil-gas studies implied that the effects of soil physical properties such as bulk density (i.e., compaction level), soil particle size are key parameters to understand landfill gaseous performance. The gas exchange through the final cover soils is controlled by advective and diffusive gas transport. Air permeability (ka) governs the advective gas transport while the soil-gas diffusion coefficient (Dp) governs diffusive gas transport. In this study, the effects of compaction level and particle size fraction effects on ka and Dp for landfill final cover soil was investigated. The disturbed soil samples were taken from landfill final cover in Japan. A compaction tests were performed for the soil samples with two different size fractions (content , the soil samples were repacked into soil cores (i.d. 15-cm, length 12-cm, 2120 cm3) at two different compaction levels [(MP):2700 kN/m2 and (SP):600 kN/m2]. After the compaction tests, ka and Dp were measured and then samples were saturated and subsequently drained at different soil-water matric potential of 0.98, 2.94, 9.81, 1235 kPa and with air-dried and oven-dried conditions. Results showed that measured Dp and ka values for the coarser (content. Further, compaction effort was much significant

  9. Parameter-free driven Liouville-von Neumann approach for time-dependent electronic transport simulations in open quantum systems

    DEFF Research Database (Denmark)

    Zelovich, Tamar; Hansen, Thorsten; Liu, Fulai

    2017-01-01

    A parameter-free version of the recently developed driven Liouville-von Neumann equation [T. Zelovich et al., J. Chem. Theory Comput. 10(8), 2927-2941 (2014)] for electronic transport calculations in molecular junctions is presented. The single driving rate, appearing as a fitting parameter in th......-box" algorithms to simulate electron dynamics in open quantum systems out of equilibrium.......A parameter-free version of the recently developed driven Liouville-von Neumann equation [T. Zelovich et al., J. Chem. Theory Comput. 10(8), 2927-2941 (2014)] for electronic transport calculations in molecular junctions is presented. The single driving rate, appearing as a fitting parameter...

  10. Petrophysical and transport parameters evolution during acid percolation through structurally different limestones

    Science.gov (United States)

    Martinez Perez, Laura; Luquot, Linda

    2017-04-01

    Processes affecting geological media often show complex and unpredictable behavior due to the presence of heterogeneities. This remains problematic when facing contaminant transport problems, in the CO2 storage industry or dealing with the mechanisms underneath natural processes where chemical reactions can be observed during the percolation of rock non-equilibrated fluid (e.g. karst formation, seawater intrusion). To understand the mechanisms taking place in a porous medium as a result of this water-rock interaction, we need to know the flow parameters that control them, and how they evolve with time as a result of that concurrence. This is fundamental to ensure realistic predictions of the behavior of natural systems in response of reactive transport processes. We investigate the coupled influence of structural and hydrodynamic heterogeneities in limestone rock samples tracking its variations during chemical reactions. To do so we use laboratory petrophysical techniques such as helium porosimetry, gas permeability, centrifugue, electrical resistivity and sonic waves measurements to obtain the parameters that characterize flow within rock matrix (porosity, permeability, retention curve and pore size distribution, electrical conductivity, formation factor, cementation index and tortuosity) before and after percolation experiments. We built an experimental setup that allows injection of acid brine into core samples under well controlled conditions, monitor changes in hydrodynamic properties and obtain the chemical composition of the injected solution at different stages. 3D rock images were also acquired before and after the experiments using a micro-CT to locate the alteration processes and perform an acurate analysis of the structural changes. Two limestones with distinct textural classification and thus contrasting transport properties have been used in the laboratory experiments: a crinoid limestone and an oolithic limestone. Core samples dimensions were 1 inch

  11. Linking particle and pore-size distribution parameters to soil gas transport properties

    DEFF Research Database (Denmark)

    Arthur, Emmanuel; Møldrup, Per; Schjønning, Per

    2012-01-01

    Accurate estimation of soil gas diffusivity (Dp/Do, the ratio of gas diffusion coefficients in soil and free air) and air permeability (ka) from basic texture and pore characteristics will be highly valuable for modeling soil gas transport and emission and their field-scale variations. From......, respectively) and the Campbell water retention parameter b were used to characterize particle and pore size distributions, respectively. Campbell b yielded a wide interval (4.6–26.2) and was highly correlated with α, β, and volumetric clay content. Both Dp/Do and ka followed simple power-law functions (PLFs...... also well (but relatively more weakly) correlated with the basic soil characteristics, again with the best correlations to volumetric clay content and b. As a first attempt at developing a simple Dp/Do model useful at the field scale, we extended the classical Buckingham Dp/Do model (εa2) by a scaling...

  12. Modeling of microfluidic microbial fuel cells using quantitative bacterial transport parameters

    Science.gov (United States)

    Mardanpour, Mohammad Mahdi; Yaghmaei, Soheila; Kalantar, Mohammad

    2017-02-01

    The objective of present study is to analyze the dynamic modeling of bioelectrochemical processes and improvement of the performance of previous models using quantitative data of bacterial transport parameters. The main deficiency of previous MFC models concerning spatial distribution of biocatalysts is an assumption of initial distribution of attached/suspended bacteria on electrode or in anolyte bulk which is the foundation for biofilm formation. In order to modify this imperfection, the quantification of chemotactic motility to understand the mechanisms of the suspended microorganisms' distribution in anolyte and/or their attachment to anode surface to extend the biofilm is implemented numerically. The spatial and temporal distributions of the bacteria, as well as the dynamic behavior of the anolyte and biofilm are simulated. The performance of the microfluidic MFC as a chemotaxis assay is assessed by analyzing the bacteria activity, substrate variation, bioelectricity production rate and the influences of external resistance on the biofilm and anolyte's features.

  13. Quantitative extraction of the jet transport parameter from combined data at RHIC and LHC

    CERN Document Server

    Wang, Xin-Nian

    2014-01-01

    Using theoretical tools developed by the JET Collaboration in which one employes 2+1D or 3+1D hydrodynamic models for the bulk medium evolution and jet quenching models, the combined data on suppression of single inclusive hadron spectra at both RHIC and LHC are systematically analyzed with five different approaches to the parton energy loss. The jet transport parameter is extracted from the best fits to the data with values of $\\hat q \\approx 1.2\\pm 0.3$ and $1.9\\pm 0.7$ GeV$^2$/fm in the center of the most central Au+Au collisions at $\\sqrt{s}=200$ GeV and Pb+Pb collisions at $\\sqrt{s}=2.67$ TeV, respectively at an initial time $\\tau_0=0.6$ fm/$c$ for a quark jet with an initial energy of 10 GeV/$c$.

  14. Transport parameters for pulsed ultrasonic waves propagating in an aluminum foam

    Science.gov (United States)

    Tourin, Arnaud; Derode, Arnaud; Mamou, Victor; Fink, Mathias; Page, John; Cowan, Michael L.

    2002-11-01

    Aluminum foams have now been studied for many years in large part because of their applications as light-weight elastic materials (e.g., car bumpers, aerospace engineering applications). The pore size and the spatial distribution of the pores govern the mechanical behavior of the foam and can vary enormously depending on the method of manufacturing. Thus, new methods for the nondestructive characterization of these materials are needed. We present here a set of experimental ultrasonic methods in a range of frequencies where the ultrasonic waves are multiply scattered in the medium. In this regime, the propagation is described by ultrasonic transport parameters which are related to the microstructure of the foam. The diffusion coefficient and the absorption mean free path have been determined in pulse transmission experiments by fitting the solution of the diffusion equation to the average intensity, the so-called time of flight distribution. To more fully characterize the medium, the transport mean path and the diffusion coefficient have been measured in backscattering experiments using the static and dynamic coherent backscattering effects. For both methods, the properties of the sample interfaces have been taken into account.

  15. Processes and parameters involved in modeling radionuclide transport from bedded salt repositories. Final report. Technical memorandum

    Energy Technology Data Exchange (ETDEWEB)

    Evenson, D.E.; Prickett, T.A.; Showalter, P.A.

    1979-07-01

    The parameters necessary to model radionuclide transport in salt beds are identified and described. A proposed plan for disposal of the radioactive wastes generated by nuclear power plants is to store waste canisters in repository sites contained in stable salt formations approximately 600 meters below the ground surface. Among the principal radioactive wastes contained in these canisters will be radioactive isotopes of neptunium, americium, uranium, and plutonium along with many highly radioactive fission products. A concern with this form of waste disposal is the possibility of ground-water flow occurring in the salt beds and endangering water supplies and the public health. Specifically, the research investigated the processes involved in the movement of radioactive wastes from the repository site by groundwater flow. Since the radioactive waste canisters also generate heat, temperature is an important factor. Among the processes affecting movement of radioactive wastes from a repository site in a salt bed are thermal conduction, groundwater movement, ion exchange, radioactive decay, dissolution and precipitation of salt, dispersion and diffusion, adsorption, and thermomigration. In addition, structural changes in the salt beds as a result of temperature changes are important. Based upon the half-lives of the radioactive wastes, he period of concern is on the order of a million years. As a result, major geologic phenomena that could affect both the salt bed and groundwater flow in the salt beds was considered. These phenomena include items such as volcanism, faulting, erosion, glaciation, and the impact of meteorites. CDM reviewed all of the critical processes involved in regional groundwater movement of radioactive wastes and identified and described the parameters that must be included to mathematically model their behavior. In addition, CDM briefly reviewed available echniques to measure these parameters.

  16. Calibration of the Transport Parameters of a Local Problem of Water Quality in Igap\\'o I Lake

    CERN Document Server

    Romeiro, Neyva M L; Cirilo, Eliandro R; Natti, Paulo L

    2011-01-01

    The calibration of a model refers to the process by which one can estimate some parameters by comparisons with observed data. Due to the dynamical nature of the environment, variations between predicted and observed values occur. Thus, the environmental parameters may vary due to random temperature changes, time of discharge flow, time of the day, and other conditions. Such variations can be minimized by identifying and optimizing some parameters of the transport model, like the values of diffusion coefficients in x and y directions and the kinetic parameter that describes the process of removing pollutants. This paper presents results concerning the calibration of transport parameters for two-dimensional problems of water quality (fecal coliform control) at Igap\\'o I Lake, located in Londrina, Paran\\'a, Brazil. Thus, the convection-diffusion-reaction equation, which describes mathematically the process studied in this work, is resolved by a semidiscrete finite element method (SUPG) which combines finite diff...

  17. Global Source Parameters from Regional Spectral Ratios for Yield Transportability Studies

    Science.gov (United States)

    Phillips, W. S.; Fisk, M. D.; Stead, R. J.; Begnaud, M. L.; Rowe, C. A.

    2016-12-01

    We use source parameters such as moment, corner frequency and high frequency rolloff as constraints in amplitude tomography, ensuring that spectra of well-studied earthquakes are recovered using the ensuing attenuation and site term model. We correct explosion data for path and site effects using such models, which allows us to test transportability of yield estimation techniques based on our best source spectral estimates. To develop a background set of source parameters, we applied spectral ratio techniques to envelopes of a global set of regional distance recordings from over 180,000 crustal events. Corner frequencies and moment ratios were determined via inversion using all event pairs within predetermined clusters, shifting to absolute levels using independently determined regional and teleseismic moments. The moment and corner frequency results can be expressed as stress drop, which has considerable scatter, yet shows dramatic regional patterns. We observe high stress in subduction zones along S. America, S. Mexico, the Banda Sea, and associated with the Yakutat Block in Alaska. We also observe high stress at the Himalayan syntaxes, the Pamirs, eastern Iran, the Caspian, the Altai-Sayan, and the central African rift. Low stress is observed along mid ocean spreading centers, the Afar rift, patches of convergence zones such as Nicaragua, the Zagros, Tibet, and the Tien Shan, among others. Mine blasts appear as low stress events due to their low corners and steep rolloffs. Many of these anomalies have been noted by previous studies, and we plan to compare results directly. As mentioned, these results will be used to constrain tomographic imaging, but can also be used in model validation procedures similar to the use of ground truth in location problems, and, perhaps most importantly, figure heavily in quality control of local and regional distance amplitude measurements.

  18. Elucidating the Performance Limitations of Lithium-ion Batteries due to Species and Charge Transport through Five Characteristic Parameters

    Science.gov (United States)

    Jiang, Fangming; Peng, Peng

    2016-01-01

    Underutilization due to performance limitations imposed by species and charge transports is one of the key issues that persist with various lithium-ion batteries. To elucidate the relevant mechanisms, two groups of characteristic parameters were proposed. The first group contains three characteristic time parameters, namely: (1) te, which characterizes the Li-ion transport rate in the electrolyte phase, (2) ts, characterizing the lithium diffusion rate in the solid active materials, and (3) tc, describing the local Li-ion depletion rate in electrolyte phase at the electrolyte/electrode interface due to electrochemical reactions. The second group contains two electric resistance parameters: Re and Rs, which represent respectively, the equivalent ionic transport resistance and the effective electronic transport resistance in the electrode. Electrochemical modeling and simulations to the discharge process of LiCoO2 cells reveal that: (1) if te, ts and tc are on the same order of magnitude, the species transports may not cause any performance limitations to the battery; (2) the underlying mechanisms of performance limitations due to thick electrode, high-rate operation, and large-sized active material particles as well as effects of charge transports are revealed. The findings may be used as quantitative guidelines in the development and design of more advanced Li-ion batteries. PMID:27599870

  19. The Role of Microbial Electron Transfer in the Coevolution of the Biosphere and Geosphere.

    Science.gov (United States)

    Jelen, Benjamin I; Giovannelli, Donato; Falkowski, Paul G

    2016-09-01

    All life on Earth is dependent on biologically mediated electron transfer (i.e., redox) reactions that are far from thermodynamic equilibrium. Biological redox reactions originally evolved in prokaryotes and ultimately, over the first ∼2.5 billion years of Earth's history, formed a global electronic circuit. To maintain the circuit on a global scale requires that oxidants and reductants be transported; the two major planetary wires that connect global metabolism are geophysical fluids-the atmosphere and the oceans. Because all organisms exchange gases with the environment, the evolution of redox reactions has been a major force in modifying the chemistry at Earth's surface. Here we briefly review the discovery and consequences of redox reactions in microbes with a specific focus on the coevolution of life and geochemical phenomena.

  20. AECL strategy for surface-based investigations of potential disposal sites and the development of a geosphere model for a site

    Energy Technology Data Exchange (ETDEWEB)

    Whitaker, S.H.; Brown, A.; Davison, C.C.; Gascoyne, M.; Lodha, G.S.; Stevenson, D.R.; Thorne, G.A.; Tomsons, D. [AECL Research, Whiteshell Labs., Pinawa, MB (Canada)

    1994-05-01

    The objective of this report is to summarize AECL`s strategy for surface-based geotechnical site investigations used in screening and evaluating candidate areas and candidate sites for a nuclear fuel waste repository and for the development of geosphere models of sites. The report is one of several prepared by national nuclear fuel waste management programs for the Swedish Nuclear Fuel and Waste Management Co. (SKB) to provide international background on site investigations for SKB`s R and D programme on siting.The scope of the report is limited to surface-based investigations of the geosphere, those done at surface or in boreholes drilled from surface. The report discusses AECL`s investigation strategy and the methods proposed for use in surface-based reconnaissance and detailed site investigations at potential repository sites. Site investigations done for AECL`s Underground Research Laboratory are used to illustrate the approach. The report also discusses AECL`s strategy for developing conceptual and mathematical models of geological conditions at sites and the use of these models in developing a model (Geosphere Model) for use in assessing the performance of the disposal system after a repository is closed. Models based on the site data obtained at the URL are used to illustrate the approach. Finally, the report summarizes the lessons learned from AECL`s R and D program on site investigations and mentions some recent developments in the R and D program. 120 refs, 33 figs, 7 tabs.

  1. Comparing Variability of Parameters between Roller Bed Brakes Testers and Dynamometric Platform of Ministry Of Transport Facilities

    Directory of Open Access Journals (Sweden)

    Senabre C

    2015-01-01

    Full Text Available This study gives a comparison between which parameters may vary when braking on two different Ministry of Transport (MOT brake testers, such as roller bed brake tester and dynamometric platform. A comparative study between both types of brake testers have been carried out by the mechanical engineering staffs at the mechanical laboratory at the Miguel Hernández University in Elche to determinate which parameters can vary the result of the test.

  2. Sensitivity Analysis of Hydrological Parameters in Modeling Flow and Transport in the Unsaturated Zone of Yucca Mountain

    Energy Technology Data Exchange (ETDEWEB)

    K. Zhang; Y.S. Wu; J.E. Houseworth

    2006-03-21

    The unsaturated fractured volcanic deposits at Yucca Mountain have been intensively investigated as a possible repository site for storing high-level radioactive waste. Field studies at the site have revealed that there exist large variabilities in hydrological parameters over the spatial domain of the mountain. This paper reports on a systematic analysis of hydrological parameters using the site-scale 3-D unsaturated zone (UZ) flow model. The objectives of the sensitivity analyses are to evaluate the effects of uncertainties in hydrologic parameters on modeled UZ flow and contaminant transport results. Sensitivity analyses are carried out relative to fracture and matrix permeability and capillary strength (van Genuchten a), through variation of these parameter values by one standard deviation from the base-case values. The parameter variation results in eight parameter sets. Modeling results for the eight UZ flow sensitivity cases have been compared with field observed data and simulation results from the base-case model. The effects of parameter uncertainties on the flow fields are discussed and evaluated through comparison of results for flow and transport. In general, this study shows that uncertainties in matrix parameters cause larger uncertainty in simulated moisture flux than corresponding uncertainties in fracture properties for unsaturated flow through heterogeneous fractured rock.

  3. Sensitivity Analysis Of Hydrological Parameters In Modeling FlowAnd Transport In The Unsaturated Zone Of Yucca Mountain

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Keni; Wu, Yu-Shu; Houseworth, James E

    2006-02-01

    The unsaturated fractured volcanic deposits at Yucca Mountain in Nevada, USA, have been intensively investigated as a possible repository site for storing high-level radioactive waste. Field studies at the site have revealed that there exist large variabilities in hydrological parameters over the spatial domain of the mountain. Systematic analyses of hydrological parameters using a site-scale three-dimensional unsaturated zone (UZ) flow model have been undertaken. The main objective of the sensitivity analyses was to evaluate the effects of uncertainties in hydrologic parameters on modeled UZ flow and contaminant transport results. Sensitivity analyses were carried out relative to fracture and matrix permeability and capillary strength (van Genuchten {alpha}) through variation of these parameter values by one standard deviation from the base-case values. The parameter variation resulted in eight parameter sets. Modeling results for the eight UZ flow sensitivity cases have been compared with field observed data and simulation results from the base-case model. The effects of parameter uncertainties on the flow fields were evaluated through comparison of results for flow and transport. In general, this study shows that uncertainties in matrix parameters cause larger uncertainty in simulated moisture flux than corresponding uncertainties in fracture properties for unsaturated flow through heterogeneous fractured rock.

  4. Using dual-domain advective-transport simulation to reconcile multiple-tracer ages and estimate dual-porosity transport parameters

    Science.gov (United States)

    Sanford, Ward E.; Niel Plummer, L.; Casile, Gerolamo; Busenberg, Ed; Nelms, David L.; Schlosser, Peter

    2017-06-01

    Dual-domain transport is an alternative conceptual and mathematical paradigm to advection-dispersion for describing the movement of dissolved constituents in groundwater. Here we test the use of a dual-domain algorithm combined with advective pathline tracking to help reconcile environmental tracer concentrations measured in springs within the Shenandoah Valley, USA. The approach also allows for the estimation of the three dual-domain parameters: mobile porosity, immobile porosity, and a domain exchange rate constant. Concentrations of CFC-113, SF6, 3H, and 3He were measured at 28 springs emanating from carbonate rocks. The different tracers give three different mean composite piston-flow ages for all the springs that vary from 5 to 18 years. Here we compare four algorithms that interpret the tracer concentrations in terms of groundwater age: piston flow, old-fraction mixing, advective-flow path modeling, and dual-domain modeling. Whereas the second two algorithms made slight improvements over piston flow at reconciling the disparate piston-flow age estimates, the dual-domain algorithm gave a very marked improvement. Optimal values for the three transport parameters were also obtained, although the immobile porosity value was not well constrained. Parameter correlation and sensitivities were calculated to help quantify the uncertainty. Although some correlation exists between the three parameters being estimated, a watershed simulation of a pollutant breakthrough to a local stream illustrates that the estimated transport parameters can still substantially help to constrain and predict the nature and timing of solute transport. The combined use of multiple environmental tracers with this dual-domain approach could be applicable in a wide variety of fractured-rock settings.

  5. Integrated Hydrogeophysical and Hydrogeologic Driven Parameter Upscaling for Dual-Domain Transport Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Gregory Flach; Mary Harris; Susan Hubbard; Camelia Knapp; Mike Kowalsky; Maggie Millings; John Shafer; Mike Waddell

    2006-06-01

    Our research project is motivated by the observations that conventional characterization approaches capture only a fraction of heterogeneity affecting field-scale transport, and that conventional modeling approaches, which use this sparse data, typically do not successfully predict long term plume behavior with sufficient accuracy to guide remedial strategies. Our working hypotheses are that improved prediction of contaminant transport can be achieved using a dual-domain transport approach and field-scale characterization approaches.

  6. Geosphere-biosphere interactions in bio-activity volcanic lakes: evidences from Hule and Rìo Cuarto (Costa Rica).

    Science.gov (United States)

    Cabassi, Jacopo; Tassi, Franco; Mapelli, Francesca; Borin, Sara; Calabrese, Sergio; Rouwet, Dmitri; Chiodini, Giovanni; Marasco, Ramona; Chouaia, Bessem; Avino, Rosario; Vaselli, Orlando; Pecoraino, Giovannella; Capecchiacci, Francesco; Bicocchi, Gabriele; Caliro, Stefano; Ramirez, Carlos; Mora-Amador, Raul

    2014-01-01

    Hule and Río Cuarto are maar lakes located 11 and 18 km N of Poás volcano along a 27 km long fracture zone, in the Central Volcanic Range of Costa Rica. Both lakes are characterized by a stable thermic and chemical stratification and recently they were affected by fish killing events likely related to the uprising of deep anoxic waters to the surface caused by rollover phenomena. The vertical profiles of temperature, pH, redox potential, chemical and isotopic compositions of water and dissolved gases, as well as prokaryotic diversity estimated by DNA fingerprinting and massive 16S rRNA pyrosequencing along the water column of the two lakes, have highlighted that different bio-geochemical processes occur in these meromictic lakes. Although the two lakes host different bacterial and archaeal phylogenetic groups, water and gas chemistry in both lakes is controlled by the same prokaryotic functions, especially regarding the CO2-CH4 cycle. Addition of hydrothermal CO2 through the bottom of the lakes plays a fundamental priming role in developing a stable water stratification and fuelling anoxic bacterial and archaeal populations. Methanogens and methane oxidizers as well as autotrophic and heterotrophic aerobic bacteria responsible of organic carbon recycling resulted to be stratified with depth and strictly related to the chemical-physical conditions and availability of free oxygen, affecting both the CO2 and CH4 chemical concentrations and their isotopic compositions along the water column. Hule and Río Cuarto lakes were demonstrated to contain a CO2 (CH4, N2)-rich gas reservoir mainly controlled by the interactions occurring between geosphere and biosphere. Thus, we introduced the term of bio-activity volcanic lakes to distinguish these lakes, which have analogues worldwide (e.g. Kivu: D.R.C.-Rwanda; Albano, Monticchio and Averno: Italy; Pavin: France) from volcanic lakes only characterized by geogenic CO2 reservoir such as Nyos and Monoun (Cameroon).

  7. Geosphere-Biosphere Interactions in Bio-Activity Volcanic Lakes: Evidences from Hule and Rìo Cuarto (Costa Rica)

    Science.gov (United States)

    Cabassi, Jacopo; Tassi, Franco; Mapelli, Francesca; Borin, Sara; Calabrese, Sergio; Rouwet, Dmitri; Chiodini, Giovanni; Marasco, Ramona; Chouaia, Bessem; Avino, Rosario; Vaselli, Orlando; Pecoraino, Giovannella; Capecchiacci, Francesco; Bicocchi, Gabriele; Caliro, Stefano; Ramirez, Carlos; Mora-Amador, Raul

    2014-01-01

    Hule and Río Cuarto are maar lakes located 11 and 18 km N of Poás volcano along a 27 km long fracture zone, in the Central Volcanic Range of Costa Rica. Both lakes are characterized by a stable thermic and chemical stratification and recently they were affected by fish killing events likely related to the uprising of deep anoxic waters to the surface caused by rollover phenomena. The vertical profiles of temperature, pH, redox potential, chemical and isotopic compositions of water and dissolved gases, as well as prokaryotic diversity estimated by DNA fingerprinting and massive 16S rRNA pyrosequencing along the water column of the two lakes, have highlighted that different bio-geochemical processes occur in these meromictic lakes. Although the two lakes host different bacterial and archaeal phylogenetic groups, water and gas chemistry in both lakes is controlled by the same prokaryotic functions, especially regarding the CO2-CH4 cycle. Addition of hydrothermal CO2 through the bottom of the lakes plays a fundamental priming role in developing a stable water stratification and fuelling anoxic bacterial and archaeal populations. Methanogens and methane oxidizers as well as autotrophic and heterotrophic aerobic bacteria responsible of organic carbon recycling resulted to be stratified with depth and strictly related to the chemical-physical conditions and availability of free oxygen, affecting both the CO2 and CH4 chemical concentrations and their isotopic compositions along the water column. Hule and Río Cuarto lakes were demonstrated to contain a CO2 (CH4, N2)-rich gas reservoir mainly controlled by the interactions occurring between geosphere and biosphere. Thus, we introduced the term of bio-activity volcanic lakes to distinguish these lakes, which have analogues worldwide (e.g. Kivu: D.R.C.-Rwanda; Albano, Monticchio and Averno: Italy; Pavin: France) from volcanic lakes only characterized by geogenic CO2 reservoir such as Nyos and Monoun (Cameroon). PMID

  8. Geosphere-biosphere interactions in bio-activity volcanic lakes: evidences from Hule and Rio Cuarto (Costa Rica.

    Directory of Open Access Journals (Sweden)

    Jacopo Cabassi

    Full Text Available Hule and Río Cuarto are maar lakes located 11 and 18 km N of Poás volcano along a 27 km long fracture zone, in the Central Volcanic Range of Costa Rica. Both lakes are characterized by a stable thermic and chemical stratification and recently they were affected by fish killing events likely related to the uprising of deep anoxic waters to the surface caused by rollover phenomena. The vertical profiles of temperature, pH, redox potential, chemical and isotopic compositions of water and dissolved gases, as well as prokaryotic diversity estimated by DNA fingerprinting and massive 16S rRNA pyrosequencing along the water column of the two lakes, have highlighted that different bio-geochemical processes occur in these meromictic lakes. Although the two lakes host different bacterial and archaeal phylogenetic groups, water and gas chemistry in both lakes is controlled by the same prokaryotic functions, especially regarding the CO2-CH4 cycle. Addition of hydrothermal CO2 through the bottom of the lakes plays a fundamental priming role in developing a stable water stratification and fuelling anoxic bacterial and archaeal populations. Methanogens and methane oxidizers as well as autotrophic and heterotrophic aerobic bacteria responsible of organic carbon recycling resulted to be stratified with depth and strictly related to the chemical-physical conditions and availability of free oxygen, affecting both the CO2 and CH4 chemical concentrations and their isotopic compositions along the water column. Hule and Río Cuarto lakes were demonstrated to contain a CO2 (CH4, N2-rich gas reservoir mainly controlled by the interactions occurring between geosphere and biosphere. Thus, we introduced the term of bio-activity volcanic lakes to distinguish these lakes, which have analogues worldwide (e.g. Kivu: D.R.C.-Rwanda; Albano, Monticchio and Averno: Italy; Pavin: France from volcanic lakes only characterized by geogenic CO2 reservoir such as Nyos and Monoun

  9. Effect of Moderate Alcohol Consumption on Parameters of Reverse Cholesterol Transport in Postmenopausal Women

    NARCIS (Netherlands)

    Sierksma, A.; Vermunt, S.H.F.; Lankhuizen, I.M.; Gaag, M.S. van der; Scheek, L.M.; Grobbee, D.E.; Tol, A. van; Hendriks, H.F.J.

    2004-01-01

    Background: Alcohol consumption is associated with increased high-density lipoprotein (HDL) cholesterol levels. One of the main antiatherogenic functions of HDL is reverse cholesterol transport. Three early steps of reverse cholesterol transport are (1) cellular cholesterol efflux, (2) plasma choles

  10. Field-scale water flow and solute transport : Swap model concepts, parameter estimation and case studies

    NARCIS (Netherlands)

    Dam, van J.C.

    2000-01-01

    Water flow and solute transport in top soils are important elements in many environmental studies. The agro- and ecohydrological model SWAP (Soil-Water-Plant-Atmosphere) has been developed to simulate simultaneously water flow, solute transport, heat flow and crop growth at field scale level. The ma

  11. Measurement of a new parameter representing the gas transport properties of the catalyst layers of polymer electrolyte fuel cells.

    Science.gov (United States)

    Iden, Hiroshi; Ohma, Atsushi; Tokunaga, Tomomi; Yokoyama, Kouji; Shinohara, Kazuhiko

    2016-05-14

    The optimization of the catalyst layers is necessary for obtaining a better fuel cell performance and reducing fuel cell cost. Although the ionomer coverage of the Pt catalyst is said to be a key parameter in this regard, the proportion of Pt either directly or indirectly covered by the ionomer is thought to be an important parameter with regard to gas transport (indirectly covered Pt: its gas transport paths are completely blocked by the ionomer even if it does not directly cover Pt). In this study, a new technique has been developed for evaluating the proportion of Pt covered indirectly or directly by the ionomer, which is defined as the "capped proportion", based on the carbon monoxide (CO) adsorption properties at different temperatures. The validity of the method was thoroughly examined by identifying the CO adsorption properties of the components of the catalyst layers. The capped proportion and oxygen transport resistance in the catalyst layers showed a good correlation, indicating that the capped proportion is a dominant factor of oxygen transport resistance. This technique thus enables the evaluation of the dominant factor of the gas transport properties of the catalyst layers. The method has another significant advantage in that it does not require a membrane electrode assembly, let alone electrochemical measurement, which should be helpful for catalyst layer optimization.

  12. Electron transport system activity of microfouling material: Relationships with biomass parameters

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Tulaskar, A.; Wagh, A.B.

    Microfouling material developed on aluminium panels immersed in surface waters of the Dona Paula Bay, Goa India was analysed for biomass (measured as dry weight, organic crabon, protein and chlorophyll @ia@@) and electron transport system actitity...

  13. Uncertainty for calculating transport on Titan: a probabilistic description of bimolecular diffusion parameters

    CERN Document Server

    Plessis, Sylvain; Mandt, Kathy; Greathouse, Thomas; Luspay-Kuti, Adrienn

    2015-01-01

    Bimolecular diffusion coefficients are important parameters used by atmospheric models to calculate altitude profiles of minor constituents in an atmosphere. Unfortunately, laboratory measurements of these coefficients were never conducted at temperature conditions relevant to the atmosphere of Titan. Here we conduct a detailed uncertainty analysis of the bimolecular diffusion coefficient parameters as applied to Titan's upper atmosphere to provide a better understanding of the impact of uncertainty for this parameter on models. Because temperature and pressure conditions are much lower than the laboratory conditions in which bimolecular diffusion parameters were measured, we apply a Bayesian framework, a problem-agnostic framework, to determine parameter estimates and associated uncertainties. We solve the Bayesian calibration problem using the open-source QUESO library which also performs a propagation of uncertainties in the calibrated parameters to temperature and pressure conditions observed in Titan's u...

  14. A Nonlinear Solute Transport Model and Data Reconstruction with Parameter Determination in an Undisturbed Soil-Column Experiment

    Directory of Open Access Journals (Sweden)

    Gongsheng Li

    2011-01-01

    Full Text Available A real undisturbed soil-column infiltrating experiment in Zibo, Shandong, China, is investigated, and a nonlinear transport model for a solute ion penetrating through the column is put forward by using nonlinear Freundlich's adsorption isotherm. Since Freundlich's exponent and adsorption coefficient and source/sink terms in the model cannot be measured directly, an inverse problem of determining these parameters is encountered based on additional breakthrough data. Furthermore, an optimal perturbation regularization algorithm is introduced to determine the unknown parameters simultaneously. Numerical simulations are carried out and then the inversion algorithm is applied to solve the real inverse problem and reconstruct the measured data successfully. The computational results show that the nonlinear advection-dispersion equation discussed in this paper can be utilized by hydrogeologists to research solute transport behaviors with nonlinear adsorption in porous medium.

  15. Effect of Porosity and Concentration Polarization on Electrolyte Diffusive Transport Parameters through Ceramic Membranes with Similar Nanopore Size

    Directory of Open Access Journals (Sweden)

    Virginia Romero

    2014-08-01

    Full Text Available Diffusive transport through nanoporous alumina membranes (NPAMs produced by the two-step anodization method, with similar pore size but different porosity, is studied by analyzing membrane potential measured with NaCl solutions at different concentrations. Donnan exclusion of co-ions at the solution/membrane interface seem to exert a certain control on the diffusive transport of ions through NPAMs with low porosity, which might be reduced by coating the membrane surface with appropriated materials, as it is the case of SiO2. Our results also show the effect of concentration polarization at the membrane surface on ionic transport numbers (or diffusion coefficients for low-porosity and high electrolyte affinity membranes, which could mask values of those characteristic electrochemical parameters.

  16. Distribution features of cuttings bed and sensitivity analysis of major drilling parameters for cuttings transport in gas drilling horizontal wells

    Institute of Scientific and Technical Information of China (English)

    祝效华; 易静; 刘清友

    2015-01-01

    In the current engineering methods for the gas horizontal drilling, the distribution features of cuttings bed remain an issue to be cleared, and the gas horizontal drilling is still in early stages of development. For on-site drilling, a 3-D transient model is established in this paper to simulate the distribution features and the transport mechanism of the cuttings bed, based on the gas-solid two-phase flow theory. The effects of major drilling parameters, such as the gas velocity, the drill pipe rotation, the cutting size and the eccentricity, on the cuttings transport efficiency are analyzed. The major findings of this study include that the cuttings begin to settle down and build up a fixed cuttings bed, in the most evident regions in front and behind the connector, the dominant parameter of the wellbore cleaning is the gas velocity, and, as the cutting size is increased, the thickness of the cuttings bed developed in the wellbore increases significantly. In addition, the eccentricity has some influence on the cuttings transport, and the drill pipe rotation has little effect on the cuttings transport.

  17. "A space-time ensemble Kalman filter for state and parameter estimation of groundwater transport models"

    Science.gov (United States)

    Briseño, Jessica; Herrera, Graciela S.

    2010-05-01

    Herrera (1998) proposed a method for the optimal design of groundwater quality monitoring networks that involves space and time in a combined form. The method was applied later by Herrera et al (2001) and by Herrera and Pinder (2005). To get the estimates of the contaminant concentration being analyzed, this method uses a space-time ensemble Kalman filter, based on a stochastic flow and transport model. When the method is applied, it is important that the characteristics of the stochastic model be congruent with field data, but, in general, it is laborious to manually achieve a good match between them. For this reason, the main objective of this work is to extend the space-time ensemble Kalman filter proposed by Herrera, to estimate the hydraulic conductivity, together with hydraulic head and contaminant concentration, and its application in a synthetic example. The method has three steps: 1) Given the mean and the semivariogram of the natural logarithm of hydraulic conductivity (ln K), random realizations of this parameter are obtained through two alternatives: Gaussian simulation (SGSim) and Latin Hypercube Sampling method (LHC). 2) The stochastic model is used to produce hydraulic head (h) and contaminant (C) realizations, for each one of the conductivity realizations. With these realization the mean of ln K, h and C are obtained, for h and C, the mean is calculated in space and time, and also the cross covariance matrix h-ln K-C in space and time. The covariance matrix is obtained averaging products of the ln K, h and C realizations on the estimation points and times, and the positions and times with data of the analyzed variables. The estimation points are the positions at which estimates of ln K, h or C are gathered. In an analogous way, the estimation times are those at which estimates of any of the three variables are gathered. 3) Finally the ln K, h and C estimate are obtained using the space-time ensemble Kalman filter. The realization mean for each one

  18. A comparison of four inverse approaches to groundwater flow and transport parameter identification

    DEFF Research Database (Denmark)

    Keidser, Allan; Rosbjerg, Dan

    1991-01-01

    of the log transmissivities are obtained by repeating the optimization of stage one. The formulated objective functions are minimized using Levenberg-Marquardt's algorithm. The models are applied to synthetic two-dimensional transport problems in steady state flow regimes. The "true" log transmissivity...

  19. The effect of plasma fluctuations on parallel transport parameters in the SOL

    DEFF Research Database (Denmark)

    Havlíčková, E.; Fundamenski, W.; Naulin, Volker

    2011-01-01

    in the scrape-off layer (SOL) taking into account these fluctuations is presented. Plasma transport in the SOL along the magnetic field between two targets is calculated by a one-dimensional fluid code in order to estimate the response to transient conditions along the SOL and the attention is given...

  20. Assessment of nitrate transport parameters using the advection-diffusion cell.

    Science.gov (United States)

    Aljazzar, Taiseer; Al-Qinna, Mohammed

    2016-11-01

    This study aimed to better understand nitrate transport in the soil system in a part of the state of North Rhine-Westphalia, in Germany, and to aid in the development of groundwater protection plans. An advection-diffusion (AD) cell was used in a miscible displacement experiment setup to characterize nitrate transport in 12 different soil samples from the study area. The three nitrate sorption isotherms were tested to define the exact nitrate interaction with the soil matrix. Soils varied in their properties which in its turn explain the variations in nitrate transport rates. Soil texture and organic matter content showed to have the most important effect on nitrate recovery and retardation. The miscible displacement experiment indicated a decrease in retardation by increasing sand fraction, and an increase in retardation by increasing soil organic matter content. Soil samples with high sand fractions (up to 94 %) exhibited low nitrate sorption capacity of less than 10 %, while soils with high organic matter content showed higher sorption of about 30 %. Based on parameterization for nitrate transport equation, the pore water velocity for both sandy and loamy soils were significantly different (P nitrate transport in soils associated with high organic matter was due to fine pore pathways clogged by fine organic colloids. It is expected that the existing micro-phobicity increased the nitrate recovery from 9 to 32 % resulting in maximum diffusion rates of about 3.5 × 10(-5) m/s(2) in sandy soils (sample number CS-04) and about 1.4 × 10(-7) m/s(2) in silt loam soils (sample number FS-02).

  1. Utilizing High-Performance Computing to Investigate Parameter Sensitivity of an Inversion Model for Vadose Zone Flow and Transport

    Science.gov (United States)

    Fang, Z.; Ward, A. L.; Fang, Y.; Yabusaki, S.

    2011-12-01

    High-resolution geologic models have proven effective in improving the accuracy of subsurface flow and transport predictions. However, many of the parameters in subsurface flow and transport models cannot be determined directly at the scale of interest and must be estimated through inverse modeling. A major challenge, particularly in vadose zone flow and transport, is the inversion of the highly-nonlinear, high-dimensional problem as current methods are not readily scalable for large-scale, multi-process models. In this paper we describe the implementation of a fully automated approach for addressing complex parameter optimization and sensitivity issues on massively parallel multi- and many-core systems. The approach is based on the integration of PNNL's extreme scale Subsurface Transport Over Multiple Phases (eSTOMP) simulator, which uses the Global Array toolkit, with the Beowulf-Cluster inspired parallel nonlinear parameter estimation software, BeoPEST in the MPI mode. In the eSTOMP/BeoPEST implementation, a pre-processor generates all of the PEST input files based on the eSTOMP input file. Simulation results for comparison with observations are extracted automatically at each time step eliminating the need for post-process data extractions. The inversion framework was tested with three different experimental data sets: one-dimensional water flow at Hanford Grass Site; irrigation and infiltration experiment at the Andelfingen Site; and a three-dimensional injection experiment at Hanford's Sisson and Lu Site. Good agreements are achieved in all three applications between observations and simulations in both parameter estimates and water dynamics reproduction. Results show that eSTOMP/BeoPEST approach is highly scalable and can be run efficiently with hundreds or thousands of processors. BeoPEST is fault tolerant and new nodes can be dynamically added and removed. A major advantage of this approach is the ability to use high-resolution geologic models to preserve

  2. Determination of technical and economic parameters of an ionic transport membrane air separation unit working in a supercritical power plant

    Directory of Open Access Journals (Sweden)

    Kotowicz Janusz

    2016-09-01

    Full Text Available In this paper an air separation unit was analyzed. The unit consisted of: an ionic transport membrane contained in a four-end type module, an air compressor, an expander fed by gas that remains after oxygen separation and heat exchangers which heat the air and recirculated flue gas to the membrane operating temperature (850 °C. The air separation unit works in a power plant with electrical power equal to 600 MW. This power plant additionally consists of: an oxy-type pulverized-fuel boiler, a steam turbine unit and a carbon dioxide capture unit. Life steam parameters are 30 MPa/650 °C and reheated steam parameters are 6 MPa/670 °C. The listed units were analyzed. For constant electrical power of the power plant technical parameters of the air separation unit for two oxygen recovery rate (65% and 95% were determined. One of such parameters is ionic membrane surface area. In this paper the formulated equation is presented. The remaining technical parameters of the air separation unit are, among others: heat exchange surface area, power of the air compressor, power of the expander and auxiliary power. Using the listed quantities, the economic parameters, such as costs of air separation unit and of individual components were determined. These quantities allowed to determine investment costs of construction of the air separation unit. In addition, they were compared with investment costs for the entire oxy-type power plant.

  3. Transport Parameters For Positive IONS In Pure H2O DC Discharge

    Science.gov (United States)

    Petrovic, Zoran; Stojanovic, Vladimir; Jovanovic, Jasmina; Maric, Dragana

    2016-09-01

    Transport properties of positive ions originating from H2O (H2O+, OH+) in DC fields and at the room temperature were calculated by using Monte Carlo simulation technique. Initially, the relevant cross section sets were assessed by using Denpoh-Nanbu theory for resolving between elastic and reactive collision events and then resolving contribution of exothermic processes from available experimental data. Newest experimentally or theoretically determined cross sections were compiled and included wherever possible. We present transport coefficients for low and moderate reduced electric fields E / N (N-gas density) accounting for non-conservative processes. Acknowledgment to Ministry of Education, Science and Technology of Republic Serbia, Projects No. 171037 and 410011.

  4. Determination of Transport Parameters in Unsaturated Zone by Tracer Experiment in the Porous Aquifer located at Ljubljana, Slovenia

    Science.gov (United States)

    Vidmar, S.; Cencur Curk, B.

    2009-04-01

    The gravel sandy aquifer of Ljubljansko polje is the source of drinking water for nearly 300.000 inhabitants of the Ljubljana city and vicinity. There are two main waterworks: Kleče and Hrastje. The plain area of Ljubljansko polje is a tectonic sink and consists of river sediments that can reach in thickness more than 100 m in the deepest part. The bedrock is the impermeable permocarbonic clayey shale, mudstones and sandstones. The hydraulic conductivity of Ljubljansko polje sediments is very good, from 10-2 m/s in the central part to 3.7•10-3 m/s on the borders of the plain. The average groundwater level is 20 m below surface. A numerical groundwater flow model was established for the wider area of the Ljubljansko polje aquifer. The fore mentioned model was not calibrated on solute transport parameters but only on water levels and this lead to unreliability in the transport model and its predictions of pollution scenarios. The transport model needs to calculate reliable scenarios of pollution dispersion, which can only be achieved with the application of real transport parameters. Human activities in the area of the Hrastje waterworks of Ljubljana threaten to degrade groundwater quality. For this reason several tracer experiments were carried out in the past. Despite a great risk, the experiments were performed on the catchment area of the Hrastje waterworks, inside the second water protection zone. During the experiments the water from Hrastje waterworks was still in use for drinking water supply. The tracer experiments were carried out in order to determine the solute transport parameters such as advection, dispersion and sorption. The research proved that the tracers could be used safely on sensitive area and that the researchers are capable and qualified to carry it out with a highest level of security. Since none of the past tracer experiments, carried out in the same area, gave us any detailed information on pollutant spreading in unsaturated zone a new

  5. Impact of Soil Water Flux on Vadose Zone Solute Transport Parameters

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The transport processes of solutes in two soil columns filled with undisturbed soil material collected from an unsaturated sandy aquifer formation in Belgium subjected to a variable upper boundary condition were identified from breakthrough curves measured by means of time domain refiectometry (TDR). Solute breakthrough was measured with 3 TDR probes inserted into each soil column at three different depths at a 10 minutes time interval. In addition, soil water content and pressure head were measured at 3 different depths. Analytical solute transport models were used to estimate the solute dispersion coefficient and average pore-water velocity from the observed breakthrough curves. The results showed that the analytical solutions were suitable in fitting the observed solute transport. The dispersion coefficient was found to be a function of the soil depth and average pore-water velocity, imposed by the soil water flux. The mobile moisture content on the other hand was not correlated with the average pore-water velocity and the dispersion coefficient.

  6. Modeling Parameters of Reliability of Technological Processes of Hydrocarbon Pipeline Transportation

    Directory of Open Access Journals (Sweden)

    Shalay Viktor

    2016-01-01

    Full Text Available On the basis of methods of system analysis and parametric reliability theory, the mathematical modeling of processes of oil and gas equipment operation in reliability monitoring was conducted according to dispatching data. To check the quality of empiric distribution coordination , an algorithm and mathematical methods of analysis are worked out in the on-line mode in a changing operating conditions. An analysis of physical cause-and-effect relations mechanism between the key factors and changing parameters of technical systems of oil and gas facilities is made, the basic types of technical distribution parameters are defined. Evaluation of the adequacy the analyzed parameters of the type of distribution is provided by using a criterion A.Kolmogorov, as the most universal, accurate and adequate to verify the distribution of continuous processes of complex multiple-technical systems. Methods of calculation are provided for supervising by independent bodies for risk assessment and safety facilities.

  7. Final Technical Report - Integrated Hydrogeophysical and Hydrogeologic Driven Parameter Upscaling for Dual-Domain Transport Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Shafer, John M

    2012-11-05

    The three major components of this research were: 1. Application of minimally invasive, cost effective hydrogeophysical techniques (surface and borehole), to generate fine scale (~1m or less) 3D estimates of subsurface heterogeneity. Heterogeneity is defined as spatial variability in hydraulic conductivity and/or hydrolithologic zones. 2. Integration of the fine scale characterization of hydrogeologic parameters with the hydrogeologic facies to upscale the finer scale assessment of heterogeneity to field scale. 3. Determination of the relationship between dual-domain parameters and practical characterization data.

  8. Compaction parameters and technologies in forest- and long- distance transportation of wood fuels; Tiivistaemisparametrit ja -tekniikat puupolttoaineiden metsae- ja kaukokuljetuksessa

    Energy Technology Data Exchange (ETDEWEB)

    Kaipainen, H. [VTT Energy, Jyvaeskylae (Finland)

    1997-12-01

    The objective of the research is to increase the level of knowledge by the aid of systematic research on the timber and the compacting of the fragments of it for forest and lorry transportation. Theoretical information on the compacting phenomena, and the factors effecting on them, will be composed in the study, and the compacting techniques with different raw materials will be studied experimentally. The objective is to reduce the forest transportation costs by 10 % and those of lorry transportation by 15 - 20 % depending on the raw material to be transported. The data obtained in the researches carried out both in Finland and abroad will be investigated in the project. The data consists also of the baling and bundling of felling residues and small-diameter wood. A test equipment, by which the compacting parameters of first thinning pine and spruce felling residues will be determined under winter conditions, was constructed to serve the experimental part of the research. The compacting tests were started at the end of January 1997, so the results of the tests will be available for the final report of 1997 in March 1997. (orig.)

  9. Transport of cerium oxide nanoparticles in saturated silica media: influences of operational parameters and aqueous chemical conditions

    Science.gov (United States)

    Zhang, Zhaohan; Gao, Peng; Qiu, Ye; Liu, Guohong; Feng, Yujie; Wiesner, Mark

    2016-10-01

    This paper aimed to investigate the influences of operational parameters and aqueous chemical conditions on transport behaviors of cerium oxides nanoparticles (CeO2-NPs) in saturated silica media. Results indicated that increasing rates of attachment efficiency (α) were related with cationic types, and critical deposition concentration (CDC) for divalent cation (Ca2+ and Mg2+) were more than 31-fold of that for monovalent cation (Na+ and K+). Increase or reduction of electrolyte pH could both promote the mobility of CeO2-NPs in glass beads, while influence was more evident at alkaline conditions. α increased linearly with NPs concentrations, while decreased linearly with flow velocity in the column, and effects were related with electrolyte contents. Presence of surfactants could sharply decreased α, and SDS was more effective to facilitate CeO2-NPs transport than Triton X-100. With DOMs concentrations increasing, α firstly kept constant, then sharply declined, and finally reduced very slowly. The influence of DOMs on NPs deposition was in order of SA > HA > TA >  BSA. Overall, this study revealed that aqueous chemical conditions was crucial to NPs transport in porous media, and would provide significant information for our understanding on the fate and transport of nanoparticles in natural environment.

  10. Compilation of data for radionuclide transport analysis

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-11-01

    This report is one of the supporting documents to the updated safety assessment (project SAFE) of the Swedish repository for low and intermediate level waste, SFR 1. A number of calculation cases for quantitative analysis of radionuclide release and dose to man are defined based on the expected evolution of the repository, geosphere and biosphere in the Base Scenario and other scenarios selected. The data required by the selected near field, geosphere and biosphere models are given and the values selected for the calculations are compiled in tables. The main sources for the selected values of the migration parameters in the repository and geosphere models are the safety assessment of a deep repository for spent fuel, SR 97, and the preliminary safety assessment of a repository for long-lived, low- and intermediate level waste, SFL 3-5. For the biosphere models, both site-specific data and generic values of the parameters are selected. The applicability of the selected parameter values is discussed and the uncertainty is qualitatively addressed for data to the repository and geosphere migration models. Parameter values selected for these models are in general pessimistic in order not to underestimate the radionuclide release rates. It is judged that this approach combined with the selected calculation cases will illustrate the effects of uncertainties in processes and events that affects the evolution of the system as well as in quantitative data that describes this. The biosphere model allows for probabilistic calculations and the uncertainty in input data are quantified by giving minimum, maximum and mean values as well as the type of probability distribution function.

  11. An Iterative Ensemble Kalman Filter with One-Step-Ahead Smoothing for State-Parameters Estimation of Contaminant Transport Models

    KAUST Repository

    Gharamti, M. E.

    2015-05-11

    The ensemble Kalman filter (EnKF) is a popular method for state-parameters estimation of subsurface flow and transport models based on field measurements. The common filtering procedure is to directly update the state and parameters as one single vector, which is known as the Joint-EnKF. In this study, we follow the one-step-ahead smoothing formulation of the filtering problem, to derive a new joint-based EnKF which involves a smoothing step of the state between two successive analysis steps. The new state-parameters estimation scheme is derived in a consistent Bayesian filtering framework and results in separate update steps for the state and the parameters. This new algorithm bears strong resemblance with the Dual-EnKF, but unlike the latter which first propagates the state with the model then updates it with the new observation, the proposed scheme starts by an update step, followed by a model integration step. We exploit this new formulation of the joint filtering problem and propose an efficient model-integration-free iterative procedure on the update step of the parameters only for further improved performances. Numerical experiments are conducted with a two-dimensional synthetic subsurface transport model simulating the migration of a contaminant plume in a heterogenous aquifer domain. Contaminant concentration data are assimilated to estimate both the contaminant state and the hydraulic conductivity field. Assimilation runs are performed under imperfect modeling conditions and various observational scenarios. Simulation results suggest that the proposed scheme efficiently recovers both the contaminant state and the aquifer conductivity, providing more accurate estimates than the standard Joint and Dual EnKFs in all tested scenarios. Iterating on the update step of the new scheme further enhances the proposed filter’s behavior. In term of computational cost, the new Joint-EnKF is almost equivalent to that of the Dual-EnKF, but requires twice more model

  12. Complex step-based low-rank extended Kalman filtering for state-parameter estimation in subsurface transport models

    KAUST Repository

    El Gharamti, Mohamad

    2014-02-01

    The accuracy of groundwater flow and transport model predictions highly depends on our knowledge of subsurface physical parameters. Assimilation of contaminant concentration data from shallow dug wells could help improving model behavior, eventually resulting in better forecasts. In this paper, we propose a joint state-parameter estimation scheme which efficiently integrates a low-rank extended Kalman filtering technique, namely the Singular Evolutive Extended Kalman (SEEK) filter, with the prominent complex-step method (CSM). The SEEK filter avoids the prohibitive computational burden of the Extended Kalman filter by updating the forecast along the directions of error growth only, called filter correction directions. CSM is used within the SEEK filter to efficiently compute model derivatives with respect to the state and parameters along the filter correction directions. CSM is derived using complex Taylor expansion and is second order accurate. It is proven to guarantee accurate gradient computations with zero numerical round-off errors, but requires complexifying the numerical code. We perform twin-experiments to test the performance of the CSM-based SEEK for estimating the state and parameters of a subsurface contaminant transport model. We compare the efficiency and the accuracy of the proposed scheme with two standard finite difference-based SEEK filters as well as with the ensemble Kalman filter (EnKF). Assimilation results suggest that the use of the CSM in the context of the SEEK filter may provide up to 80% more accurate solutions when compared to standard finite difference schemes and is competitive with the EnKF, even providing more accurate results in certain situations. We analyze the results based on two different observation strategies. We also discuss the complexification of the numerical code and show that this could be efficiently implemented in the context of subsurface flow models. © 2013 Elsevier B.V.

  13. A multidisciplinary effort to assign realistic source parameters to models of volcanic ash-cloud transport and dispersion during eruptions

    Science.gov (United States)

    Mastin, L.G.; Guffanti, M.; Servranckx, R.; Webley, P.; Barsotti, S.; Dean, K.; Durant, A.; Ewert, J.W.; Neri, A.; Rose, William I.; Schneider, D.; Siebert, L.; Stunder, B.; Swanson, G.; Tupper, A.; Volentik, A.; Waythomas, C.F.

    2009-01-01

    During volcanic eruptions, volcanic ash transport and dispersion models (VATDs) are used to forecast the location and movement of ash clouds over hours to days in order to define hazards to aircraft and to communities downwind. Those models use input parameters, called "eruption source parameters", such as plume height H, mass eruption rate ???, duration D, and the mass fraction m63 of erupted debris finer than about 4??{symbol} or 63????m, which can remain in the cloud for many hours or days. Observational constraints on the value of such parameters are frequently unavailable in the first minutes or hours after an eruption is detected. Moreover, observed plume height may change during an eruption, requiring rapid assignment of new parameters. This paper reports on a group effort to improve the accuracy of source parameters used by VATDs in the early hours of an eruption. We do so by first compiling a list of eruptions for which these parameters are well constrained, and then using these data to review and update previously studied parameter relationships. We find that the existing scatter in plots of H versus ??? yields an uncertainty within the 50% confidence interval of plus or minus a factor of four in eruption rate for a given plume height. This scatter is not clearly attributable to biases in measurement techniques or to well-recognized processes such as elutriation from pyroclastic flows. Sparse data on total grain-size distribution suggest that the mass fraction of fine debris m63 could vary by nearly two orders of magnitude between small basaltic eruptions (??? 0.01) and large silicic ones (> 0.5). We classify eleven eruption types; four types each for different sizes of silicic and mafic eruptions; submarine eruptions; "brief" or Vulcanian eruptions; and eruptions that generate co-ignimbrite or co-pyroclastic flow plumes. For each eruption type we assign source parameters. We then assign a characteristic eruption type to each of the world's ??? 1500

  14. Characteristic parameters of diffusive supersonic radiation transport in low density materials

    Institute of Scientific and Technical Information of China (English)

    Jiang Shao-En; Yang Jia-Min; Zheng Zhi-Jian; Ding Yong-Kun

    2007-01-01

    Diffusive heat waves play an important role in radiation hydrodynamics. In low density material, it may be possible that the radiative energy flux dominates the material energy flux and thus energy flow can be determined. In this paper by means of a simple algebraic method, the expressions characterizing the condition of diffusion approximation and supersonic transport of heat wave are found. In this case, the ratio of the radiative energy flux to the material energy flux is directly proportional to the product of Mach number M multiplied by optical depth τ. And it may also be expressed by radiation temperature heating material. The materiel density and length may be determined in order to aceve above-mentioned conditions when the driven temperature and duration are given.

  15. Colloid facilitated transport in fractured rock : parameter estimation and comparison with experimental data

    Energy Technology Data Exchange (ETDEWEB)

    Viswanathan, H. S. (Hari Selvi); Wolfsberg, A. V. (Andrew V.)

    2002-01-01

    Many contaminants in groundwater strongly interact with the immobile porous matrix, which retards their movement relative to groundwater flow. Colloidal particles, which are often present in groundwater, have a relatively small size and large specific surface area which makes it possible for them to also adsorb pollutants. The sorption of tracers to colloids may enhance their mobility in groundwater, relative to the case where colloids are not present. A class of pollutants for which colloid-facilitated transport may be of particular significance are radioactive isotopes. A major reason for why geologic repositories are considered suitable for the disposal of spent nuclear fuel is the strong affinity of many radionuclides to adsorb onto the porous matrix. Therefore, radionuclides accidentally released, would be contained in the geological media by adsorption or filtration until sufficient decay takes place. However, the presence of colloids may enhance radionuclide mobility in the groundwater, and reduce the efficiency of geologic media to act as a natural barrier.

  16. Evaluation of transport parameters for PVC based polyvinyl alcohol Ce(IV) phosphate composite membrane

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Mohammad Mujahid Ali, E-mail: mujahidchemistry@gmail.com [Membrane Research Laboratory, Department of Chemistry, Aligarh Muslim University, Aligarh, 202002 (India); Rafiuddin,; Inamuddin [Department of Applied Chemistry, Faculty of Engineering and Technology, Aligarh Muslim University, Aligarh-202002 (India)

    2013-05-01

    The aim of this study was to investigate the preparation of novel membrane and the characterization of their properties. A new class of polyvinyl chloride (PVC) based polyvinyl alcohol Ce(IV) phosphate composite membrane was successfully prepared by solution casting method. The structural formation was confirmed by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and morphological studies. The thermal property was investigated by thermogravimetry analysis (TGA) method. The order of surface charge density for various electrolytes was found to be LiCl < NaCl < KCl. - Highlights: ► Transport properties of composite membrane are evaluated. ► TMS method is used for electrochemical characterization. ► Membrane was found to be mechanically stable. ► The order of surface charge density was found to be LiCl < NaCl < KCl.

  17. Computation of probabilistic hazard maps and source parameter estimation for volcanic ash transport and dispersion

    Energy Technology Data Exchange (ETDEWEB)

    Madankan, R. [Department of Mechanical and Aerospace Engineering, University at Buffalo (United States); Pouget, S. [Department of Geology, University at Buffalo (United States); Singla, P., E-mail: psingla@buffalo.edu [Department of Mechanical and Aerospace Engineering, University at Buffalo (United States); Bursik, M. [Department of Geology, University at Buffalo (United States); Dehn, J. [Geophysical Institute, University of Alaska, Fairbanks (United States); Jones, M. [Center for Computational Research, University at Buffalo (United States); Patra, A. [Department of Mechanical and Aerospace Engineering, University at Buffalo (United States); Pavolonis, M. [NOAA-NESDIS, Center for Satellite Applications and Research (United States); Pitman, E.B. [Department of Mathematics, University at Buffalo (United States); Singh, T. [Department of Mechanical and Aerospace Engineering, University at Buffalo (United States); Webley, P. [Geophysical Institute, University of Alaska, Fairbanks (United States)

    2014-08-15

    Volcanic ash advisory centers are charged with forecasting the movement of volcanic ash plumes, for aviation, health and safety preparation. Deterministic mathematical equations model the advection and dispersion of these plumes. However initial plume conditions – height, profile of particle location, volcanic vent parameters – are known only approximately at best, and other features of the governing system such as the windfield are stochastic. These uncertainties make forecasting plume motion difficult. As a result of these uncertainties, ash advisories based on a deterministic approach tend to be conservative, and many times over/under estimate the extent of a plume. This paper presents an end-to-end framework for generating a probabilistic approach to ash plume forecasting. This framework uses an ensemble of solutions, guided by Conjugate Unscented Transform (CUT) method for evaluating expectation integrals. This ensemble is used to construct a polynomial chaos expansion that can be sampled cheaply, to provide a probabilistic model forecast. The CUT method is then combined with a minimum variance condition, to provide a full posterior pdf of the uncertain source parameters, based on observed satellite imagery. The April 2010 eruption of the Eyjafjallajökull volcano in Iceland is employed as a test example. The puff advection/dispersion model is used to hindcast the motion of the ash plume through time, concentrating on the period 14–16 April 2010. Variability in the height and particle loading of that eruption is introduced through a volcano column model called bent. Output uncertainty due to the assumed uncertain input parameter probability distributions, and a probabilistic spatial-temporal estimate of ash presence are computed.

  18. Sensitivity of geological, geochemical and hydrologic parameters in complex reactive transport systems for in-situ uranium bioremediation

    Science.gov (United States)

    Yang, G.; Maher, K.; Caers, J.

    2015-12-01

    Groundwater contamination associated with remediated uranium mill tailings is a challenging environmental problem, particularly within the Colorado River Basin. To examine the effectiveness of in-situ bioremediation of U(VI), acetate injection has been proposed and tested at the Rifle pilot site. There have been several geologic modeling and simulated contaminant transport investigations, to evaluate the potential outcomes of the process and identify crucial factors for successful uranium reduction. Ultimately, findings from these studies would contribute to accurate predictions of the efficacy of uranium reduction. However, all these previous studies have considered limited model complexities, either because of the concern that data is too sparse to resolve such complex systems or because some parameters are assumed to be less important. Such simplified initial modeling, however, limits the predictive power of the model. Moreover, previous studies have not yet focused on spatial heterogeneity of various modeling components and its impact on the spatial distribution of the immobilized uranium (U(IV)). In this study, we study the impact of uncertainty on 21 parameters on model responses by means of recently developed distance-based global sensitivity analysis (DGSA), to study the main effects and interactions of parameters of various types. The 21 parameters include, for example, spatial variability of initial uranium concentration, mean hydraulic conductivity, and variogram structures of hydraulic conductivity. DGSA allows for studying multi-variate model responses based on spatial and non-spatial model parameters. When calculating the distances between model responses, in addition to the overall uranium reduction efficacy, we also considered the spatial profiles of the immobilized uranium concentration as target response. Results show that the mean hydraulic conductivity and the mineral reaction rate are the two most sensitive parameters with regard to the overall

  19. Changes in the blood parameters of the Amazonian manatee (Trichechus inunguis after long-distance transportation - doi: 10.4025/actascibiolsci.v35i4.20081

    Directory of Open Access Journals (Sweden)

    Talita Laurie Lustosa do Carmo

    2013-07-01

    Full Text Available In this study we report the hematological, biochemical and hormonal parameters in a juvenile male Amazonian manatee measured before transport, immediately after transport, and during adaptation to a new facility. The animal was transported from Manaus, Amazonas, Brazil, to São Paulo, São Paulo, Brazil, (2,733 km within 6 hours. Among all blood parameters analyzed, we observed obvious neutrophilia, lymphopenia, and increases in the neutrophil/lymphocyte ratio and serum glucose and aspartate aminotransferase (AST levels, but these parameters subsequently returned to normal. These results suggest that transport and changes in the environment are temporary stressful events for Amazonian manatees. We, therefore, recommend monitoring the hematological and biochemical parameters before and after translocation to minimize the effects of handling stressors in this species

  20. Inversion of Source and Transport Parameters of Relativistic SEPs from Neutron Monitor Data

    Science.gov (United States)

    Agueda, Neus; Bütikofer, Rolf; Vainio, Rami; Heber, Bernd; Afanasiev, Alexander; Malandraki, Olga E.

    2016-04-01

    We present a new methodology to study the release processes of relativistic solar energetic particles (SEPs) based on the direct inversion of Ground Level Enhancements (GLEs) observed by the worldwide network of neutron monitors (NMs). The new approach makes use of several models, including: the propagation of relativistic SEPs from the Sun to the Earth, their transport in the Earth's magnetosphere and atmosphere, as well as the detection of the nucleon component of the secondary cosmic rays by ground based NMs. The combination of these models allows us to compute the expected ground-level NM counting rates for a series of instantaneous releases from the Sun. The amplitudes of the source components are then inferred by fitting the NM observations with the modeled NM counting rate increases. Within the HESPERIA project, we will develop the first software package for the direct inversion of GLEs and we will make it freely available for the solar and heliospheric communities. Acknowledgement: This work has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 637324.

  1. Experimental determination of metal sorption and transport parameters for graphene oxide

    Science.gov (United States)

    Duster, Thomas Alan

    The goal of this dissertation is to measure the ability of graphene oxide (GO) to sorb protons and metals, and to assess its mobility in saturated porous media. In Chapter 2 and Chapter 3, we illustrate that multi-layered GO (MLGO) exhibits a striking capacity to buffer aqueous solutions and sorb metals, with the sorption behaviors being influenced in varying degrees by pH and ionic strength. We use surface complexation modeling to calculate equilibrium constants for the surface sorption reactions between MLGO and protons, Cd, Pb, and U(VI), and we account for ionic strength effects as a competition between the target adsorbate and Na from the background electrolyte. In Chapter 4, we use deposition rate coefficient measurements to establish that pH, ionic strength, and sand surface coatings all play critical roles in determining the transport of single-layered GO (SLGO) through laboratory columns. Collectively, the sorption and mobility measurements in this dissertation are tailored to better inform remediation strategies that employ GO as a sorbent in natural and engineered systems.

  2. Network Scale Modeling of Lymph Transport and Its Effective Pumping Parameters.

    Science.gov (United States)

    Jamalian, Samira; Davis, Michael J; Zawieja, David C; Moore, James E

    2016-01-01

    The lymphatic system is an open-ended network of vessels that run in parallel to the blood circulation system. These vessels are present in almost all of the tissues of the body to remove excess fluid. Similar to blood vessels, lymphatic vessels are found in branched arrangements. Due to the complexity of experiments on lymphatic networks and the difficulty to control the important functional parameters in these setups, computational modeling becomes an effective and essential means of understanding lymphatic network pumping dynamics. Here we aimed to determine the effect of pumping coordination in branched network structures on the regulation of lymph flow. Lymphatic vessel networks were created by building upon our previous lumped-parameter model of lymphangions in series. In our network model, each vessel is itself divided into multiple lymphangions by lymphatic valves that help maintain forward flow. Vessel junctions are modeled by equating the pressures and balancing mass flows. Our results demonstrated that a 1.5 s rest-period between contractions optimizes the flow rate. A time delay between contractions of lymphangions at the junction of branches provided an advantage over synchronous pumping, but additional time delays within individual vessels only increased the flow rate for adverse pressure differences greater than 10.5 cmH2O. Additionally, we quantified the pumping capability of the system under increasing levels of steady transmural pressure and outflow pressure for different network sizes. We observed that peak flow rates normally occurred under transmural pressures between 2 to 4 cmH2O (for multiple pressure differences and network sizes). Networks with 10 lymphangions per vessel had the highest pumping capability under a wide range of adverse pressure differences. For favorable pressure differences, pumping was more efficient with fewer lymphangions. These findings are valuable for translating experimental measurements from the single lymphangion

  3. Network Scale Modeling of Lymph Transport and Its Effective Pumping Parameters.

    Directory of Open Access Journals (Sweden)

    Samira Jamalian

    Full Text Available The lymphatic system is an open-ended network of vessels that run in parallel to the blood circulation system. These vessels are present in almost all of the tissues of the body to remove excess fluid. Similar to blood vessels, lymphatic vessels are found in branched arrangements. Due to the complexity of experiments on lymphatic networks and the difficulty to control the important functional parameters in these setups, computational modeling becomes an effective and essential means of understanding lymphatic network pumping dynamics. Here we aimed to determine the effect of pumping coordination in branched network structures on the regulation of lymph flow. Lymphatic vessel networks were created by building upon our previous lumped-parameter model of lymphangions in series. In our network model, each vessel is itself divided into multiple lymphangions by lymphatic valves that help maintain forward flow. Vessel junctions are modeled by equating the pressures and balancing mass flows. Our results demonstrated that a 1.5 s rest-period between contractions optimizes the flow rate. A time delay between contractions of lymphangions at the junction of branches provided an advantage over synchronous pumping, but additional time delays within individual vessels only increased the flow rate for adverse pressure differences greater than 10.5 cmH2O. Additionally, we quantified the pumping capability of the system under increasing levels of steady transmural pressure and outflow pressure for different network sizes. We observed that peak flow rates normally occurred under transmural pressures between 2 to 4 cmH2O (for multiple pressure differences and network sizes. Networks with 10 lymphangions per vessel had the highest pumping capability under a wide range of adverse pressure differences. For favorable pressure differences, pumping was more efficient with fewer lymphangions. These findings are valuable for translating experimental measurements from the

  4. The extended distributed microstructure model for gradient-driven transport: A two-scale model for bypassing effective parameters

    Science.gov (United States)

    Carr, E. J.; Perré, P.; Turner, I. W.

    2016-12-01

    Numerous problems involving gradient-driven transport processes-e.g., Fourier's and Darcy's law-in heterogeneous materials concern a physical domain that is much larger than the scale at which the coefficients vary spatially. To overcome the prohibitive computational cost associated with such problems, the well-established Distributed Microstructure Model (DMM) provides a two-scale description of the transport process that produces a computationally cheap approximation to the fine-scale solution. This is achieved via the introduction of sparsely distributed micro-cells that together resolve small patches of the fine-scale structure: a macroscopic equation with an effective coefficient describes the global transport and a microscopic equation governs the local transport within each micro-cell. In this paper, we propose a new formulation, the Extended Distributed Microstructure Model (EDMM), where the macroscopic flux is instead defined as the average of the microscopic fluxes within the micro-cells. This avoids the need for any effective parameters and more accurately accounts for a non-equilibrium field in the micro-cells. Another important contribution of the work is the presentation of a new and improved numerical scheme for performing the two-scale computations using control volume, Krylov subspace and parallel computing techniques. Numerical tests are carried out on two challenging test problems: heat conduction in a composite medium and unsaturated water flow in heterogeneous soils. The results indicate that while DMM is more efficient, EDMM is more accurate and is able to capture additional fine-scale features in the solution.

  5. Phase I Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada Test Site, Nye County, Nevada, Revision 0

    Energy Technology Data Exchange (ETDEWEB)

    John McCord

    2007-09-01

    This report documents transport data and data analyses for Yucca Flat/Climax Mine CAU 97. The purpose of the data compilation and related analyses is to provide the primary reference to support parameterization of the Yucca Flat/Climax Mine CAU transport model. Specific task objectives were as follows: • Identify and compile currently available transport parameter data and supporting information that may be relevant to the Yucca Flat/Climax Mine CAU. • Assess the level of quality of the data and associated documentation. • Analyze the data to derive expected values and estimates of the associated uncertainty and variability. The scope of this document includes the compilation and assessment of data and information relevant to transport parameters for the Yucca Flat/Climax Mine CAU subsurface within the context of unclassified source-term contamination. Data types of interest include mineralogy, aqueous chemistry, matrix and effective porosity, dispersivity, matrix diffusion, matrix and fracture sorption, and colloid-facilitated transport parameters.

  6. Estimation and upscaling of dual-permeability model parameters for the transport of E.coli D21g in soils with preferential flow

    Science.gov (United States)

    Dual-permeability models are increasingly used to quantify the transport of solutes and microorganisms in soils with preferential flow. An ability to accurately determine the model parameters and their variation with preferential pathway characteristics is crucial for predicting the transport of mi...

  7. Electronic Transport Parameter of Carbon Nanotube Metal-Semiconductor On-Tube Heterojunction

    Directory of Open Access Journals (Sweden)

    Sukirno

    2009-03-01

    Full Text Available Carbon Nanotubes research is one of the top five hot research topics in physics since 2006 because of its unique properties and functionalities, which leads to wide-range applications. One of the most interesting potential applications is in term of nanoelectronic device. It has been modeled carbon nanotubes heterojunction, which was built from two different carbon nanotubes, that one is metallic and the other one is semiconducting. There are two different carbon nanotubes metal-semiconductor heterojunction. The first one is built from CNT(10,10 as metallic carbon nanotube and CNT (17,0 as semiconductor carbon nanotube. The other one is built from CNT (5,5 as metallic carbon nanotube and CNT (8,0. All of the semiconducting carbon nanotubes are assumed to be a pyridine-like N-doped. Those two heterojunctions are different in term of their structural shape and diameter. It has been calculated their charge distribution and potential profile, which would be useful for the simulation of their electronic transport properties. The calculations are performed by using self-consistent method to solve Non-Homogeneous Poisson’s Equation with aid of Universal Density of States calculation method for Carbon Nanotubes. The calculations are done by varying the doping fraction of the semiconductor carbon nanotubes The electron tunneling transmission coefficient, for low energy region, also has been calculated by using Wentzel-Kramer-Brillouin (WKB approximation. From the calculation results, it is obtained that the charge distribution as well as the potential profile of this device is doping fraction dependent. It is also inferred that the WKB method is fail to be used to calculate whole of the electron tunneling coefficient in this system. It is expected that further calculation for electron tunneling coefficient in higher energy region as well as current-voltage characteristic of this system will become an interesting issue for this carbon nanotube based

  8. Structural connectivity and ionic transport in molten ZnCl 2: Optimization of chlorine interaction parameters

    Science.gov (United States)

    Ruberto, R.; Pastore, G.; Tosi, M. P.

    2010-02-01

    We report molecular-dynamics simulations of pseudoclassical models of liquid ZnCl 2 near its standard freezing point (sfp) and in thermodynamic states at higher temperature and pressure. Our calculations are firstly aimed at investigating the model sensitivity of the results for the temperature-dependent self-diffusion coefficients of the two species and for the structural connectivity of the liquid as defined in terms of corner-sharing versus edge-sharing ZnCl 4 tetrahedra. Data from coherent neutron scattering experiments near the sfp and from ionic diffusivity measurements along the standard-pressure isobar guide us to a “best” choice of the model parameters describing the electric polarizability and the van der Waals interaction coefficient of the chlorine ions. This choice also provides a consistent picture of the behaviour of the liquid under pressure: with increasing pressure the Zn ions are progressively squeezed from fourfold into sixfold coordination sites, in correspondence to crystal structures built on these two coordination states. The proposed “best” interionic force law is further tested by comparing its predictions with existing first-principles calculations on the structure of the molecular dimer Zn 2Cl 4 and with new first-principles calculations on distorted configurations of the ZnCl 2 monomer as created by extensive bond stretching or bond bending.

  9. Observations of boundary layer parameters and suspended sediment transport over the intertidal flats of northern Jiangsu, China

    Institute of Scientific and Technical Information of China (English)

    WANGYaping; GAOShu; KEXiankun

    2004-01-01

    A current-turbidity monitoring system (CTMS) was deployed on the intertidal flat at Wanggang, northern Jiangsu during October 16-17, 2000, to measure the tidal current speeds and seawater turbidities at 5 levels above the seabed. Based upon the logarithmic-prof'de equation, the boundary layer parameters, i.e., u*, Z0 and C60, were obtained for 247 tidal flow velocity prof'des. Around 90% of the profiles were logarithmic according to the critical correlation coefficient. Internal consistency analysis shows that these parameters derived by different methods are consistent with each other. In addition, the height of the bedforms observed is close to the seabed roughness lengths calculated from the velocity prof'des, indicating that the boundary layer parameters obtained can reveal the conditions at the sedimentwater interface on the intertidal flats. Suspended sediment concentrations were obtained from the 5 CTMS turbidity meters using laboratory and in-situ calibrations. The results show that the in-situ calibrated SSCs have a much higher accuracy than the laboratory calibrated ones. Calculation of suspended sediment fluxes on the intertidal flats, with a magnitude of 104 kg/m per spring tidal cycle, indicates that suspended sediment moves towards the northwest, which is reversal to the transport pattern controlled by the southward Northern Jiangsu Coastal Current in the sub-tidal zone and adjacent shallow waters.

  10. A dedicated setup for the measurement of the electron transport parameters in gases at large electric fields

    Energy Technology Data Exchange (ETDEWEB)

    Fonte, P. [Laboratorio de Instrumentacao e Fisica Experimental de Particulas, Departamento de Fisica da Universidade de Coimbra, 3004-516 Coimbra (Portugal); Instituto Superior de Engenharia de Coimbra, Rua Pedro Nunes, 3030-199 Coimbra (Portugal); Mangiarotti, A. [Laboratorio de Instrumentacao e Fisica Experimental de Particulas, Departamento de Fisica da Universidade de Coimbra, 3004-516 Coimbra (Portugal); Botelho, S.; Goncalves, J.A.C. [Instituto de Pesquisas Energeticas e Nucleares, 05508-000 Cidade Universitaria, Sao Paulo (Brazil); Departamento de Fisica, Pontificia Universidade Catolica de Sao Paulo, 01303-050 Sao Paulo (Brazil); Ridenti, M.A. [Instituto de Fisica, Universidade de Sao Paulo, 05508-090 Cidade Universitaria, Sao Paulo (Brazil); Bueno, C.C., E-mail: ccbueno@ipen.b [Instituto de Pesquisas Energeticas e Nucleares, 05508-000 Cidade Universitaria, Sao Paulo (Brazil); Departamento de Fisica, Pontificia Universidade Catolica de Sao Paulo, 01303-050 Sao Paulo (Brazil)

    2010-01-21

    Electron transport parameters are important in several areas ranging from particle detectors to plasma-assisted processing reactors. Nevertheless, especially at high fields strengths and for complex gases, relatively few data are published. A dedicated setup has been developed to measure the electron drift velocity and the first Townsend coefficient in parallel plate geometry. An RPC-like cell has been adopted to reach high field strengths without the risk of destructive sparks. The validation data obtained with pure Nitrogen will be presented and compared to a selection of the available literature and to calculations performed with Magboltz 2 version 8.6. The new data collected in pure Isobutane will then be discussed. This is the first time the electron drift velocity in pure Isobutane is measured well into the saturation region. Good agreement is found with expectations from Magboltz.

  11. Soil-Gas Phase Transport and Structure Parameters for a Soil Under Different Management Regimes and at Two Moisture Levels

    DEFF Research Database (Denmark)

    Eden, Marie; Møldrup, Per; Schjønning, Per

    2012-01-01

    saturation and drainage to - 100 cm of matric potential (pF2). Gas diffusivity in intact samples at fm conditions exhibited a general, linear relationship with air-filled porosity (epsilon), independent of soil texture and treatment. Comparing intact and repacked samples drained to pF2, repacked soil......Measurements of diffusive and convective gas transport parameters can be used to describe soil functional architecture and reveal key factors for soil structure development. Undisturbed 100-cm(3) soil samples were sampled at the Long-term Research on Agricultural Systems experiment located...... at the University of California, Davis. The 18 plots used in this study represented fairly wide ranges in organic carbon (0. 0072-0.0153 kg kg(-1)) and clay (0.30-0.44 kg kg(-1)). Soil-air permeability, k(a), and soil-gas diffusivity, D-P/D-0, were determined at field-moist conditions (fin) and, subsequently, after...

  12. Estrone-1-sulphate (E1S) has impact on the kinetics parameters of transporter mediated taurine and glutamate influx in Caco-2 cells

    DEFF Research Database (Denmark)

    Steffansen, Bente; El-Sayed, F

    of membrane transporters. The aim was therefore to investigate if addition of E1S to the growth medium of Caco-2 cells before but not during the influx study, change the kinetic parameters of transporter-mediated influx of taurine and glutamate by respective TAUT and EAAT transporters. The results show that 4...... days pretreatment with E1S change the concentration dependent influx curves and Km for transporter mediated taurine and Km and Jmax for glutamate influx although the effects on Km and Jmax are not significant....

  13. Testing Shelter Index and a Simple Wind Speed Parameter to Characterize Vegetation Control of Sand Transport Threshold and Flux

    Science.gov (United States)

    Gillies, John; Nield, Joanna; Nickling, William; Furtak-Cole, Eden

    2013-04-01

    Wind erosion and dust emissions occur in the Chihuahuan Desert surrounding Las Cruces NM from a range of surfaces with different types and amounts of vegetation. Understanding how vegetation modulates these processes remains a research challenge. One important aspect of research is to develop a relationship between a descriptor of the surface roughness that can be used to provide an indication of how susceptible the sediment transport system is to activation by wind. Here we present results from a study that examines the relationship between an index of shelter (distance from a point to the nearest upwind vegetation/vegetation height), as originally proposed by Okin (2008), and particle threshold expressed as a ratio of wind measured at 0.45 times the plant height divided by the wind speed at 17 m, and saltation flux (g cm-2 s-1). Saltation flux was measured using sediment traps positioned 15 cm above the surface and nearby optical gate sensors (Wenglor® model YH03PCT8)measuring saltation activity also placed at a height of 15 cm. The results are used to evaluate shelter index as a parameter to characterize the local winds as influenced by the vegetation and sediment transport conditions (threshold and transport). Wind speed, wind direction, saltation activity and point saltation flux were measured at 35 locations in defined test areas (~13,000 m2) in three vegetation communities: mature mesquite covered nebkha dunes, incipient nebkha dunes dominated by low mesquite plants, and a mature creosote bush area. Measurement positions represent the most open areas, and hence those places most susceptible to wind erosion among the vegetation elements. Shelter index was calculated for each measurement position for each approximately 10 degree wind direction bin using digital elevation models for each site acquired using terrestrial laser scanning.

  14. Investigation of current transport parameters of Ti/4H-SiC MPS diode with inhomogeneous barrier

    Institute of Scientific and Technical Information of China (English)

    Song Qing-Wen; Zhang Yu-Ming; Zhang Yi-Men; Chen Feng-Ping; Tang xiao-Yan

    2011-01-01

    The current transport parameters of 4H-SiC merged PiN Schottky (MPS) diode are investigated in a temperature range of 300-520 K. Evaluation of the experimental current-voltage (Ⅰ-Ⅴ) data reveals the decrease in Schottky barrier height φb but an increase in ideality factor n, with temperature decreasing, which suggests the presence of an inhomogeneous Schottky barrier. The current transport behaviours are analysed in detail using the Tung's model and the effective area of the low barrier patches is extracted. It is found that small low barrier patches, making only 4.3% of the total contact, may significantly influence the device electrical characteristics due to the fact that a barrier height of 0.968 eV is much lower than the average barrier height 1.39 eV. This shows that ion implantation in the Schottky contact region of MPS structure may result in a poor Ti/4H-SiC interface quality. In addition, the temperature dependence of the specific on-resistance (Ron-sp), T2.14, is determined between 300 K and 520 K, which is similar to that predicted by a reduction in electron mobility.

  15. An adaptive hybrid EnKF-OI scheme for efficient state-parameter estimation of reactive contaminant transport models

    KAUST Repository

    El Gharamti, Mohamad

    2014-09-01

    Reactive contaminant transport models are used by hydrologists to simulate and study the migration and fate of industrial waste in subsurface aquifers. Accurate transport modeling of such waste requires clear understanding of the system\\'s parameters, such as sorption and biodegradation. In this study, we present an efficient sequential data assimilation scheme that computes accurate estimates of aquifer contamination and spatially variable sorption coefficients. This assimilation scheme is based on a hybrid formulation of the ensemble Kalman filter (EnKF) and optimal interpolation (OI) in which solute concentration measurements are assimilated via a recursive dual estimation of sorption coefficients and contaminant state variables. This hybrid EnKF-OI scheme is used to mitigate background covariance limitations due to ensemble under-sampling and neglected model errors. Numerical experiments are conducted with a two-dimensional synthetic aquifer in which cobalt-60, a radioactive contaminant, is leached in a saturated heterogeneous clayey sandstone zone. Assimilation experiments are investigated under different settings and sources of model and observational errors. Simulation results demonstrate that the proposed hybrid EnKF-OI scheme successfully recovers both the contaminant and the sorption rate and reduces their uncertainties. Sensitivity analyses also suggest that the adaptive hybrid scheme remains effective with small ensembles, allowing to reduce the ensemble size by up to 80% with respect to the standard EnKF scheme. © 2014 Elsevier Ltd.

  16. From boiling point to glass transition temperature: Transport coefficients in molecular liquids follow three-parameter scaling

    Science.gov (United States)

    Schmidtke, B.; Petzold, N.; Kahlau, R.; Hofmann, M.; Rössler, E. A.

    2012-10-01

    The phenomenon of the glass transition is an unresolved problem in condensed matter physics. Its prominent feature, the super-Arrhenius temperature dependence of the transport coefficients, remains a challenge to be described over the full temperature range. For a series of molecular glass formers, we combined τ(T) collected from dielectric spectroscopy and dynamic light scattering covering a range 10-12 s < τ(T) < 102 s. Describing the dynamics in terms of an activation energy E(T), we distinguish a high-temperature regime characterized by an Arrhenius law with a constant activation energy E∞ and a low-temperature regime for which Ecoop(T) ≡ E(T)-E∞ increases exponentially while cooling. A scaling is introduced, specifically Ecoop(T)/E∞ ∝ exp[-λ(T/TA-1)], where λ is a fragility parameter and TA a reference temperature proportional to E∞. In order to describe τ(T) still the attempt time τ∞ has to be specified. Thus, a single interaction parameter E∞ describing the high-temperature regime together with λ controls the temperature dependence of low-temperature cooperative dynamics.

  17. Quantification of tracer plume transport parameters in 2D saturated porous media by cross-borehole ERT imaging

    Science.gov (United States)

    Lekmine, G.; Auradou, H.; Pessel, M.; Rayner, J. L.

    2017-04-01

    Cross-borehole ERT imaging was tested to quantify the average velocity and transport parameters of tracer plumes in saturated porous media. Seven tracer tests were performed at different flow rates and monitored by either a vertical or horizontal dipole-dipole ERT sequence. These sequences were tested to reconstruct the shape and temporally follow the spread of the tracer plumes through a background regularization procedure. Data sets were inverted with the same inversion parameters and 2D model sections of resistivity ratios were converted to tracer concentrations. Both array types provided an accurate estimation of the average pore velocity vz. The total mass Mtot recovered was always overestimated by the horizontal dipole-dipole and underestimated by the vertical dipole-dipole. The vertical dipole-dipole was however reliable to quantify the longitudinal dispersivity λz, while the horizontal dipole-dipole returned better estimation for the transverse component λx. λ and Mtot were mainly influenced by the 2D distribution of the cumulated electrical sensitivity and the Shadow Effects induced by the third dimension. The size reduction of the edge of the plume was also related to the inability of the inversion process to reconstruct sharp resistivity contrasts at the interface. Smoothing was counterbalanced by a non-realistic rise of the ERT concentrations around the centre of mass returning overpredicted total masses. A sensitivity analysis on the cementation factor m and the porosity ϕ demonstrated that a change in one of these parameters by 8% involved non negligible variations by 30 and 40% of the dispersion coefficients and mass recovery.

  18. Intestinal transporters for endogenic and pharmaceutical organic anions: the challenges of deriving in-vitro kinetic parameters for the prediction of clinically relevant drug-drug interactions.

    Science.gov (United States)

    Grandvuinet, Anne Sophie; Vestergaard, Henrik Tang; Rapin, Nicolas; Steffansen, Bente

    2012-11-01

    This review provides an overview of intestinal human transporters for organic anions and stresses the need for standardization of the various in-vitro methods presently employed in drug-drug interaction (DDI) investigations. Current knowledge on the intestinal expression of the apical sodium-dependent bile acid transporter (ASBT), the breast cancer resistance protein (BCRP), the monocarboxylate transporters (MCT) 1, MCT3-5, the multidrug resistance associated proteins (MRP) 1-6, the organic anion transporting polypetides (OATP) 2B1, 1A2, 3A1 and 4A1, and the organic solute transporter α/β (OSTα/β) has been covered along with an overview of their substrates and inhibitors. Furthermore, the many challenges in predicting clinically relevant DDIs from in-vitro studies have been discussed with focus on intestinal transporters and the various methods for deducting in-vitro parameters for transporters (K(m) /K(i) /IC50, efflux ratio). The applicability of using a cut-off value (estimated based on the intestinal drug concentration divided by the K(i) or IC50) has also been considered. A re-evaluation of the current approaches for the prediction of DDIs is necessary when considering the involvement of other transporters than P-glycoprotein. Moreover, the interplay between various processes that a drug is subject to in-vivo such as translocation by several transporters and dissolution should be considered. © 2012 The Authors. JPP © 2012 Royal Pharmaceutical Society.

  19. Development and testing of a large, transportable rainfall simulator for plot-scale runoff and parameter estimation

    Directory of Open Access Journals (Sweden)

    T. G. Wilson

    2014-04-01

    Full Text Available There is increased interest in the interplay between vegetation conditions and overland flow generation. The literature is unclear on this relationship and there is little quantitative guidance for modeling efforts. Therefore, experimental efforts are needed and these call for a lightweight transportable plot-scale (>10 m2 rainfall simulator that can be deployed quickly and quickly redeployed over various vegetation cover conditions. Accordingly, a variable intensity rainfall simulator and collection system was designed and tested in the laboratory and in the field. The system was tested with three configurations of common pressure washing nozzles producing rainfall intensities of 62, 43, and 32 mm h−1 with uniformity coefficients of 76, 65, and 62, respectively, over a plot of 15.12 m2. Field tests were carried out in on a grassy field with silt-loam soil in Orroli, Sardinia in July and August 2010, and rainfall, soil moisture, and runoff data were collected. The two-term Philip infiltration model was used to find optimal values for the saturated hydraulic conductivity of the soil surface and bulk soil, soil water retention curve slope, and air entry suction head. Optimized hydraulic conductivity values were comparable to both the measured final infiltration rate and literature values for saturated hydraulic conductivity. This inexpensive rainfall simulator can therefore be used to identify field parameters needed for hydrologic modeling.

  20. Phase II Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 98: Frenchman Flat, Nye County, Nevada, Rev. No.: 0

    Energy Technology Data Exchange (ETDEWEB)

    DeNovio, Nicole M.; Bryant, Nathan; King, Chrissi B.; Bhark, Eric; Drellack, Sigmund L.; Pickens, John F.; Farnham, Irene; Brooks, Keely M.; Reimus, Paul; Aly, Alaa

    2005-04-01

    This report documents pertinent transport data and data analyses as part of the Phase II Corrective Action Investigation (CAI) for Frenchman Flat (FF) Corrective Action Unit (CAU) 98. The purpose of this data compilation and related analyses is to provide the primary reference to support parameterization of the Phase II FF CAU transport model.

  1. Simulating tubulin-associated unit transport in an axon: using bootstrapping for estimating confidence intervals of best-fit parameter values obtained from indirect experimental data.

    Science.gov (United States)

    Kuznetsov, I A; Kuznetsov, A V

    2017-05-01

    In this paper, we first develop a model of axonal transport of tubulin-associated unit (tau) protein. We determine the minimum number of parameters necessary to reproduce published experimental results, reducing the number of parameters from 18 in the full model to eight in the simplified model. We then address the following questions: Is it possible to estimate parameter values for this model using the very limited amount of published experimental data? Furthermore, is it possible to estimate confidence intervals for the determined parameters? The idea that is explored in this paper is based on using bootstrapping. Model parameters were estimated by minimizing the objective function that simulates the discrepancy between the model predictions and experimental data. Residuals were then identified by calculating the differences between the experimental data and model predictions. New, surrogate 'experimental' data were generated by randomly resampling residuals. By finding sets of best-fit parameters for a large number of surrogate data the histograms for the model parameters were produced. These histograms were then used to estimate confidence intervals for the model parameters, by using the percentile bootstrap. Once the model was calibrated, we applied it to analysing some features of tau transport that are not accessible to current experimental techniques.

  2. Theoretical Analysis of the Influence of Process Parameters on Pathogen Transport and Fate in a Recreational Beach

    Science.gov (United States)

    Liu, L.; Fu, X.

    2010-12-01

    The US has very long shorelines (95,471 miles) contributing remarkable yearly revenue to the country by providing numerous recreational beaches. The beaches of both inland lakes and marine regions must be closed when the level of waterborne pathogens indicated by fecal indicator bacteria (FIB) including total coliform (TC), fecal coli form (FC, or Escherichia coli, E. coli) and Enterococcus exceed microbial water quality standards. Beach closures are of mounting concern to beach managers and the public due to the increasing risk to human health from waterborne pathogens. Monitoring FIB with laboratory analysis usually takes at least 18 hours during which beach goers may have been unintentionally exposed to the contaminated water. Therefore a water quality model to quickly and precisely forecast FIB has been a very effective tool for beach management to help beach managers in making decisions if beaches are safe enough to open to the public. The fate and transport of pathogens in the surf-zone of a beach area is a complex process involving various factors of hydrodynamics, hydrology, chemistry, microbiology. These factors including dispersion coefficient, wind velocity, particle settling velocity, fraction of bacteria attached, solar insolation, discharges to the beach, geometry of the beach, etc, are the essential components for a mechanistic model to describe the inactivation of FIB. To better understand the importance of these factors and their roles in impacting inactivation, transport and removal of FIB is extremely important to enhance the effectiveness and preciseness of a predictive model. The aim of this paper is to report the sensitivity analysis results of these factors in the surf zone of a creational beach using a verified water quality model system. The relative importance of these parameters is being ranked. For instance, the current sensitivity analysis shows that sunlight insolation has greater impact on pathogen inactivation than water temperature

  3. Numerical evaluation of apparent transport parameters from forced-gradient tracer tests in statistically anisotropic heterogeneous formations

    Science.gov (United States)

    Pedretti, D.; Fernandez-Garcia, D.; Bolster, D.; Sanchez-Vila, X.; Benson, D.

    2012-04-01

    For risk assessment and adequate decision making regarding remediation strategies in contaminated aquifers, solute fate in the subsurface must be modeled correctly. In practical situations, hydrodynamic transport parameters are obtained by fitting procedures, that aim to mathematically reproduce solute breakthrough (BTC) observed in the field during tracer tests. In recent years, several methods have been proposed (curve-types, moments, nonlocal formulations) but none of them combine the two main characteristic effects of convergent flow tracer tests (which are the most used tests in the practice): the intrinsic non-stationarity of the convergent flow to a well and the ubiquitous multiscale hydraulic heterogeneity of geological formations. These two effects separately have been accounted for by a lot of methods that appear to work well. Here, we investigate both effects at the same time via numerical analysis. We focus on the influence that measurable statistical properties of the aquifers (such as the variance and the statistical geometry of correlation scales) have on the shape of BTCs measured at the pumping well during convergent flow tracer tests. We built synthetic multigaussian 3D fields of heterogeneous hydraulic conductivity fields with variable statistics. A well is located in the center of the domain to reproduce a forced gradient towards it. Constant-head values are imposed on the boundaries of the domains, which have 251x251x100 cells. Injections of solutes take place by releasing particles at different distances from the well and using a random walk particle tracking scheme with constant local coefficient of dispersivity. The results show that BTCs partially display the typical anomalous behavior that has been commonly referred to as the effect of heterogeneity and connectivity (early and late arrival times of solute differ from the one predicted by local formulations). Among the most salient features, the behaviors of BTCs after the peak (the slope

  4. Forsmark site investigation. Programme for long-term observations of geosphere and biosphere after completed site investigations

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-06-15

    The site investigation at Forsmark was terminated the last of June, 2007. Hundreds of investigations have been conducted during a period of more than five years. Monitoring of a number of geoscientific parameters and biological objects has been one important part of the site investigation programme. Monitoring is defined as recurrent measurements of the same parameters/objects, so that time series are generated. Long-term monitoring of for example weather parameters, surface water discharge in brooks, and the groundwater head in a large number of boreholes has been conducted during the site investigations. Furthermore, repeated sampling of precipitation, surface water and groundwater in soil and rock for hydrochemical analyses has been carried out, and the groundwater flow in isolated borehole sections has been measured several times. Besides, some biological objects, for example rare bird species, have been invented each year of the site investigation. The measured parameters and the invented objects are characterized by a certain degree of time dependent variability, which is also site-specific. The aim of the monitoring is primarily to establish the 'undisturbed' conditions, the so called 'baseline'. If a deep repository is sited at Forsmark, many site-specific conditions will change, due to natural causes as well as to the construction works. Knowledge about the undisturbed conditions strengthens the ability to reveal and quantify such changes and to distinguish natural changes from those caused by the human activities. Another object of monitoring is to, by the study of the variability pattern of the monitored parameters, elevate the knowledge about the underlying, often complex causes governing the variations. In this way the description of site-specific conditions may be more precise and the prospects of modelling important processes are improved. After completion of the site investigations, a period of about two years will follow, when

  5. Shelter Index and a simple wind speed parameter to characterize vegetation control of sand transport threshold and Flu

    Science.gov (United States)

    Gillies, J. A.; Nield, J. M.; Nickling, W. G.; Furtak-Cole, E.

    2014-12-01

    Wind erosion and dust emissions occur in many dryland environments from a range of surfaces with different types and amounts of vegetation. Understanding how vegetation modulates these processes remains a research challenge. Here we present results from a study that examines the relationship between an index of shelter (SI=distance from a point to the nearest upwind vegetation/vegetation height) and particle threshold expressed as the ratio of wind speed measured at 0.45 times the mean plant height divided by the wind speed at 17 m when saltation commences, and saltation flux. The results are used to evaluate SI as a parameter to characterize the influence of vegetation on local winds and sediment transport conditions. Wind speed, wind direction, saltation activity and point saltation flux were measured at 35 locations in defined test areas (~13,000 m2) in two vegetation communities: mature streets of mesquite covered nebkhas and incipient nebkhas dominated by low mesquite plants. Measurement positions represent the most open areas, and hence those places most susceptible to wind erosion among the vegetation elements. Shelter index was calculated for each measurement position for each 10° wind direction bin using digital elevation models for each site acquired using terrestrial laser scanning. SI can show the susceptibility to wind erosion at different time scales, i.e., event, seasonal, or annual, but in a supply-limited system it can fail to define actual flux amounts due to a lack of knowledge of the distribution of sediment across the surface of interest with respect to the patterns of SI.

  6. Development of a road transport emission inventory for Greece and the Greater Athens Area: effects of important parameters.

    Science.gov (United States)

    Fameli, K M; Assimakopoulos, V D

    2015-02-01

    Traffic is considered one of the major polluting sectors and as a consequence a significant cause for the measured exceedances of ambient air quality limit values mainly in urban areas. The Greater Athens Area (located in Attica), the most populated area in Greece, faces severe air pollution problems due to the combination of high road traffic emissions, complex topography and local meteorological conditions. Even though several efforts were made to construct traffic emission inventories for Greece and Attica, still there is not a spatially and temporally resolved one, based on data from relevant authorities and organisations. The present work aims to estimate road emissions in Greece and Attica based on the top down approach. The programme COPERT 4 was used to calculate the annual total emissions from the road transport sector for the period 2006-2010 and an emission inventory for Greece and Attica was developed with high spatial (6 × 6 km(2) for Greece and 2 × 2 km(2) for Attica) and temporal (1-hour) resolutions. The results revealed that about 40% of national CO₂, CO, VOC and NMVOC values and 30% of NOx and particles are emitted in Attica. The fuel consumption and the subsequent reduction of annual mileage driven in combination with the import of new engine anti-pollution technologies affected CO₂, CO, VOC and NMVOC emissions. The major part of CO (56.53%) and CO₂ (66.15%) emissions was due to passenger cars (2010), while heavy duty vehicles (HDVs) were connected with NOx, PM₂.₅ and PM₁₀ emissions with 51.27%, 43.97% and 38.13% respectively (2010). The fleet composition, the penetration of diesel fuelled cars, the increase of urban average speed and the fleet renewal are among the most effective parameters towards the emission reduction strategies.

  7. The Importance of Parameter Variances, Correlations Lengths, and Cross-Correlations in Reactive Transport Models: Key Considerations for Assessing the Need for Microscale Information (Invited)

    Science.gov (United States)

    Reimus, P. W.

    2010-12-01

    A process-oriented modeling approach is implemented to examine the importance of parameter variances, correlation lengths, and especially cross-correlations in contaminant transport predictions over large scales. It is shown that the most important consideration is the correlation between flow rates and retardation processes (e.g., sorption, matrix diffusion) in the system. If flow rates are negatively correlated with retardation factors in systems containing multiple flow pathways, then characterizing these negative correlation(s) may have more impact on reactive transport modeling than microscale information. Such negative correlations are expected in porous-media systems where permeability is negatively correlated with clay content and rock alteration (which are usually associated with increased sorption). Likewise, negative correlations are expected in fractured rocks where permeability is positively correlated with fracture apertures, which in turn are negatively correlated with sorption and matrix diffusion. Parameter variances and correlation lengths are also shown to have important effects on reactive transport predictions, but they are less important than parameter cross-correlations. Microscale information pertaining to contaminant transport has become more readily available as characterization methods and spectroscopic instrumentation have achieved lower detection limits, greater resolution, and better precision. Obtaining detailed mechanistic insights into contaminant-rock-water interactions is becoming a routine practice in characterizing reactive transport processes in groundwater systems (almost necessary for high-profile publications). Unfortunately, a quantitative link between microscale information and flow and transport parameter distributions or cross-correlations has not yet been established. One reason for this is that quantitative microscale information is difficult to obtain in complex, heterogeneous systems, so simple systems that lack the

  8. Engineering and performance standards parameters for long distance road transport in the United States: the special case of horses

    Directory of Open Access Journals (Sweden)

    Carolyn L. Stull

    2008-03-01

    Full Text Available The transportation conditions of slaughter horses for human consumption have become a public and regulatory issue in the United States in the last two decades. Federal regulations were developed partially using the results of funded research projects that examined the types of vehicles, characteristics of slaughter horse candidates, types of injuries during transport, duration of transit, stocking densities and other behavioural and physiological indices during long-distance road transport. Additionally, the physiological responses of horses travelling long distances in vans while cross-tied by their halters in individual stalls were also studied. Both engineering- and performance-based standards were developed from the scientific studies and implemented in the federal regulations to ensure the humane movement of equines to slaughter facilities via commercial road transportation.

  9. Impact of a pneumatic tube system transport on hemostasis parameters measurement: the experiment of Cochin universitary hospital (AP-HP, Paris, France).

    Science.gov (United States)

    Calmette, Leyla; Ibrahim, Firas; Gouin, Isabelle; Horellou, Marie-Hélène; Mazoyer, Élisabeth; Fontenay, Michaela; Flaujac, Claire

    2017-02-01

    Samples transported by pneumatic tube system are submitted to forces of acceleration and deceleration which can affect laboratory parameters. At Cochin hospital, majority of samples of hemostasis, except for platelets tests, are transported by pneumatic tube system. The objective of this study was to evaluate the impact of a pneumatic tube system (PTS) transport compared to hand-delivered transport on samples and to qualify Cochin hospital PTS according to requirements of standard ISO 15189. A bibliographical study was made and showed that pneumatic tube system particularly influences platelets tests. Four citrate tubes were collected in 5 healthy volunteers in the maternity: 2 tubes were transported by PTS and 2 others were hand-delivered to the laboratory. Five coagulation tests were analyzed: prothrombine time (PT), activated partial thromboplastin time (aPTT), factor (F) V, FVIII and platelet closure time with PFA-100TM collagen/epinephrine. For each volunteer, the results obtained by PTS and by hand-delivered transport were compared with formula usually used for biological analysis retake: 2.8 x standard deviation of reproductibility variation coefficient (SH GTA 01, COFRAC). This study did not show an impact of PTS on PT, aPTT, FV and FVIII. For PFA-100TM collagen/epinephrine, we noted an impact on 2/5 volunteers. These results, in agreement with the literature, led to the conclusion that Cochin hospital PTS is in compliance to transport samples for usual coagulation tests except platelet tests. This study allowed to issue French recommendations for PTS transport of hemostasis tubes qualification available on "Groupe français d'hémostase et thrombose" Web site.

  10. Mass Transport within Soils

    Energy Technology Data Exchange (ETDEWEB)

    McKone, Thomas E.

    2009-03-01

    Contaminants in soil can impact human health and the environment through a complex web of interactions. Soils exist where the atmosphere, hydrosphere, geosphere, and biosphere converge. Soil is the thin outer zone of the earth's crust that supports rooted plants and is the product of climate and living organisms acting on rock. A true soil is a mixture of air, water, mineral, and organic components. The relative proportions of these components determine the value of the soil for agricultural and for other human uses. These proportions also determine, to a large extent, how a substance added to soil is transported and/or transformed within the soil (Spositio, 2004). In mass-balance models, soil compartments play a major role, functioning both as reservoirs and as the principal media for transport among air, vegetation, surface water, deeper soil, and ground water (Mackay, 2001). Quantifying the mass transport of chemicals within soil and between soil and atmosphere is important for understanding the role soil plays in controlling fate, transport, and exposure to multimedia pollutants. Soils are characteristically heterogeneous. A trench dug into soil typically reveals several horizontal layers having different colors and textures. As illustrated in Figure 1, these multiple layers are often divided into three major horizons: (1) the A horizon, which encompasses the root zone and contains a high concentration of organic matter; (2) the B horizon, which is unsaturated, lies below the roots of most plants, and contains a much lower organic carbon content; and (3) the C horizon, which is the unsaturated zone of weathered parent rock consisting of bedrock, alluvial material, glacial material, and/or soil of an earlier geological period. Below these three horizons lies the saturated zone - a zone that encompasses the area below ground surface in which all interconnected openings within the geologic media are completely filled with water. Similarly to the unsaturated

  11. Identification of TCE and PCE sorption and biodegradation parameters in a sandy aquifer for fate and transport modelling: batch and column studies

    OpenAIRE

    Kret, E.; Kiecak, A.; Malina, G.; Nijenhuis, I.; Postawa, A.

    2015-01-01

    The main aim of this study was to determine the sorption and biodegradation parameters of trichloroethene (TCE) and tetrachloroethene (PCE) as input data required for their fate and transport modelling in a Quaternary sandy aquifer. Sorption was determined based on batch and column experiments, while biodegradation was investigated using the compound-specific isotope analysis (CSIA). The aquifer materials medium (soil 1) to fine (soil 2) sands and groundwater samples came from the representat...

  12. Scanning drift tube measurements of electron transport parameters in different gases: argon, synthetic air, methane and deuterium

    Science.gov (United States)

    Korolov, I.; Vass, M.; Donkó, Z.

    2016-10-01

    Measurements of transport coefficients of electrons in a scanning drift tube apparatus are reported for different gases: argon, synthetic air, methane and deuterium. The experimental system allows the spatio-temporal development of the electron swarms (‘swarm maps’) to be recorded and this information, when compared with the profiles predicted by theory, makes it possible to determine the ‘time-of-flight’ transport coefficients: the bulk drift velocity, the longitudinal diffusion coefficient and the effective ionization coefficient, in a well-defined way. From these data, the effective Townsend ionization coefficient is determined as well. The swarm maps provide, additionally, direct, unambiguous information about the hydrodynamic/non-hydrodynamic regimes of the swarms, aiding the selection of the proper regions applicable for the determination of the transport coefficients.

  13. Attempt at determining selected parameters of gravitational transport of ash and water or ash-brine mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Postawa, J.

    1984-03-01

    This paper discusses results of laboratory investigations into hydraulic transport of hardening mixtures which are used for stowing in underground coal mines in Poland. Two types of hardening mixtures are used: fly ash from the Jaworzno I power plant or the Leg power plant and water or fly ash and brine. The following proportions of fly ash and water are used: 1.5:1, 2:1, 2.5:1 and 3.0:1. Proportion of fly ash and brine ranges from 1.5:1 to 2.5:1. Critical transport velocity of mixtures depending on physical properties of fly ash, proportion of fly ash and water or brine and pipeline diameter is determined. Equations for calculating the optimum conditions of hydraulic transport of hardening stowing are derived. Factors which influence range of hydraulic stowing and stowing efficiency are analyzed. The results of analyses are given in 6 diagrams and 4 tables. (4 refs.) (In Polish)

  14. Influence of the content of Cr in diffusive transport parameters and trapping of hydrogen in Fe alloys; Influencia del contenido de Cr en los parametros de transporte difusivos y de trapping de hidrogeno en aleaciones de Fe

    Energy Technology Data Exchange (ETDEWEB)

    Penalva, I.; Alberro, G.; Orduna, I.; Legarda, F.; Vila, R.; Ortiz, C. J.

    2013-07-01

    The materials candidates to be part of a fusion reactor must characterize properly to carry out the correct selection of the same. In this sense, the interaction of the isotopes of hydrogen with materials Such It is essential, since the transport parameters will Affect the inventory of hydrogen in the reactor Retained and, in Addition, of These components isotopes permeation through structural materials can Affect areas of human.

  15. Effects of Soil Bulk Density on Gas Transport Parameters and Pore-Network Properties across a Sandy Field Site

    DEFF Research Database (Denmark)

    Masis Melendez, Federico; de Jonge, Lis Wollesen; Chamindu, T K K Deepagoda

    2015-01-01

    The gas diffusion coefficient, air permeability, and their interrelations with air-filled porosity are crucial for characterization of diffusive and convective transport of gases in soils. Variations in soil bulk density can affect water retention, air-filled pore space, pore tortuosity...

  16. Kinetics and conductivity parameters of uptake and transport of polychlorinated biphenyls in the Caco-2 intestinal cell line model

    NARCIS (Netherlands)

    Dulfer, W.J.; Govers, H.A.J.; Groten, J.P.

    1998-01-01

    Most of the accumulation of polychlorinated biphenyls (PCBs) over the food chain can be attributed to contaminant uptake from food. The effect of fatty acid absorption on net uptake and transport fluxes of a selection of 14 PCBs over the organismal gut epithelium has been determined in monolayers of

  17. Kinetics and conductivity parameters of uptake and transport of polychlorinated biphenyls in the Caco-2 intestinal cell line model

    NARCIS (Netherlands)

    Dulfer, W.J.; Govers, H.A.J.; Groten, J.P.

    1998-01-01

    Most of the accumulation of polychlorinated biphenyls (PCBs) over the food chain can be attributed to contaminant uptake from food. The effect of fatty acid absorption on net uptake and transport fluxes of a selection of 14 PCBs over the organismal gut epithelium has been determined in monolayers of

  18. Open access and preservation of data on the coupled geosphere-biosphere system: the case of the H2020 Project ECOPOTENTIAL

    Science.gov (United States)

    Provenzale, Antonello; Nativi, Stefano

    2016-04-01

    The H2020 ECOPOTENTIAL Project addresses the entire chain of ecosystem-related services, by focusing on the interaction between the biotic and abiotic components of ecosystems (geosphere-biosphere interactions), developing ecosystem data services with special emphasis on Copernicus services, implementing model output services to distribute the results of the modelling activities, and estimating current and future ecosystem services and benefits combining ecosystem functions (supply) with beneficiaries needs (demand). In ECOPOTENTIAL all data, model results and acquired knowledge will be made available on common and open platforms, coherent with the Global Earth Observation System of Systems (GEOSS) data sharing principles and fully interoperable with the GEOSS Common Infrastructure (GCI). ECOPOTENTIAL will be conducted in the context of the implementation of the Copernicus EO Component and in synergy with the ESA Climate Change Initiative. The project activities will contribute to Copernicus and non-Copernicus contexts for ecosystems, and will create an Ecosystem Data Service for Copernicus (ECOPERNICUS), a new open-access, smart and user-friendly geospatial data/products retrieval portal and web coverage service using a dedicated online server. ECOPOTENTIAL will make data, scientific results, models and information accessible and available through a cloud-based open platform implementing virtual laboratories. The platform will be a major contribution to the GEOSS Common Infrastructure, reinforcing the GEOSS Data-CORE. By the end of the project, new prototype products and ecosystem services, based on improved access (notably via GEOSS) and long-term storage of ecosystem EO data and information in existing PAs, will be realized. In this contribution, we discuss the approach followed in the project for Open Data access and use. ECOPOTENTIAL introduced a set of architecture and interoperability principles to facilitate data (and the associated software) discovery

  19. Closed-Flow Column Experiments - A Numerical Study on Breakthrough Oscillations Reveals a Decreased Uncertainty in the Inverse Determination of Transport Parameters

    Science.gov (United States)

    Ritschel, Thomas; Totsche, Kai Uwe

    2016-04-01

    The identification of transport parameters by inverse modeling often suffers from large uncertainties due to equifinality or parameter correlation when models are fitted to observations of the solute breakthrough in column outflow experiments. This issue can be approached by increasing the information potential of the observation, e.g. by running multiple experiments at different boundary conditions. A promising complementary approach of designing soil column experiments in order to further increase the obtained information is the closed-flow mode that is characterized by the recirculation of the effluent solution into the solution supply vessel. Depending on the experimental conditions, the solute concentration in the mixing vessel and the effluent follows a damped sinusoidal oscillation. As a result, the closed-flow experiment provides additional observables in the breakthrough curve, which are the initial exponential decrease in concentration in mixing vessel concentration, the oscillation wavelength and the extent of damping, each indicative for corresponding transport parameters. Furthermore, the concentration in the porous medium and the mixing vessel converges to equilibrium due to the closed loop. The evaluation of these emergent features allows intrinsic control over boundary conditions and impacts the uncertainty of parameters in inverse modeling. We present a comprehensive numerical sensitivity analysis to illustrate the potential application of closed-flow experiments. We can show that the sensitivity with respect to the apparent dispersion can be controlled by the experimenter leading to a decrease in parameter uncertainty as compared to classical experiments by an order of magnitude for optimal settings. With these finding we are also able to show a reduction of equifinality found for situations, where rate-limited interactions impede a proper determination of the apparent dispersion and rate coefficients. This renders the closed-flow mode a useful

  20. Predicting Soil Physical Parameters and Copper Transport in a Polluted Field From X Ray CT-Images

    DEFF Research Database (Denmark)

    Paradelo Pérez, Marcos; Naveed, Muhammad; Møldrup, Per

    2013-01-01

    The development of 3D imaging techniques provides non-destructive tools to reveal the soil structure. X-ray computed tomography (CT) analysis has succeeded in predicting pore network properties such as macropore size distribution, tortuosity, and hydraulic properties. Since contaminant transport...... in soils is strongly controlled by the soil structure, the capabilities of these visualization techniques could be used to predict the risk of pollutants leaching. This work was carried out using soils from a field site (Hygum) in Jutland, Denmark, a historical copper (Cu) polluted field cultivated for 80...... to the volume of each soil column. Leaching experiments were performed to analyze tritium transport, colloid leaching and dissolved organic carbon and Cu losses associated with particles or dissolved organic matter (DOM). Air permeability and saturated hydraulic conductivity were measured before and after...

  1. A comparison of numerical solutions of partial differential equations with probabilistic and possibilistic parameters for the quantification of uncertainty in subsurface solute transport

    Science.gov (United States)

    Zhang, Kejiang; Achari, Gopal; Li, Hua

    2009-11-01

    Traditionally, uncertainty in parameters are represented as probabilistic distributions and incorporated into groundwater flow and contaminant transport models. With the advent of newer uncertainty theories, it is now understood that stochastic methods cannot properly represent non random uncertainties. In the groundwater flow and contaminant transport equations, uncertainty in some parameters may be random, whereas those of others may be non random. The objective of this paper is to develop a fuzzy-stochastic partial differential equation (FSPDE) model to simulate conditions where both random and non random uncertainties are involved in groundwater flow and solute transport. Three potential solution techniques namely, (a) transforming a probability distribution to a possibility distribution (Method I) then a FSPDE becomes a fuzzy partial differential equation (FPDE), (b) transforming a possibility distribution to a probability distribution (Method II) and then a FSPDE becomes a stochastic partial differential equation (SPDE), and (c) the combination of Monte Carlo methods and FPDE solution techniques (Method III) are proposed and compared. The effects of these three methods on the predictive results are investigated by using two case studies. The results show that the predictions obtained from Method II is a specific case of that got from Method I. When an exact probabilistic result is needed, Method II is suggested. As the loss or gain of information during a probability-possibility (or vice versa) transformation cannot be quantified, their influences on the predictive results is not known. Thus, Method III should probably be preferred for risk assessments.

  2. A comparison of numerical solutions of partial differential equations with probabilistic and possibilistic parameters for the quantification of uncertainty in subsurface solute transport.

    Science.gov (United States)

    Zhang, Kejiang; Achari, Gopal; Li, Hua

    2009-11-03

    Traditionally, uncertainty in parameters are represented as probabilistic distributions and incorporated into groundwater flow and contaminant transport models. With the advent of newer uncertainty theories, it is now understood that stochastic methods cannot properly represent non random uncertainties. In the groundwater flow and contaminant transport equations, uncertainty in some parameters may be random, whereas those of others may be non random. The objective of this paper is to develop a fuzzy-stochastic partial differential equation (FSPDE) model to simulate conditions where both random and non random uncertainties are involved in groundwater flow and solute transport. Three potential solution techniques namely, (a) transforming a probability distribution to a possibility distribution (Method I) then a FSPDE becomes a fuzzy partial differential equation (FPDE), (b) transforming a possibility distribution to a probability distribution (Method II) and then a FSPDE becomes a stochastic partial differential equation (SPDE), and (c) the combination of Monte Carlo methods and FPDE solution techniques (Method III) are proposed and compared. The effects of these three methods on the predictive results are investigated by using two case studies. The results show that the predictions obtained from Method II is a specific case of that got from Method I. When an exact probabilistic result is needed, Method II is suggested. As the loss or gain of information during a probability-possibility (or vice versa) transformation cannot be quantified, their influences on the predictive results is not known. Thus, Method III should probably be preferred for risk assessments.

  3. Prediction of Breakthrough Curves for Conservative and Reactive Transport from the Structural Parameters of Highly Heterogeneous Media

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Scott [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Haslauer, Claus P. [Univ. of Tubingen (Germany); Cirpka, Olaf A. [Univ. of Tubingen (Germany); Vesselinov, Velimir Valentinov [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-01-05

    The key points of this presentation were to approach the problem of linking breakthrough curve shape (RP-CTRW transition distribution) to structural parameters from a Monte Carlo approach and to use the Monte Carlo analysis to determine any empirical error

  4. A realistic transport model with pressure dependent parameters for gas flow in tight porous media with application to determining shale rock properties

    CERN Document Server

    Ali, Iftikhar

    2016-01-01

    Shale gas recovery has seen a major boom in recent years due to the increasing global energy demands; but the extraction technologies are very expensive. It is therefore important to develop realistic transport modelling and simulation methods, for porous rocks and porous media, that can compliment the field work. Here, a new nonlinear transport model for single phase gas flow in tight porous media is derived, incorporating many important physical processes that occur in such porous systems: continuous flow, transition flow, slip flow, Knudsen diffusion, adsorption and desorption in to and out of the rock material, and a correction for high flow rates (turbulence). This produces a nonlinear advection-diffusion type of partial differential equation (PDE) with pressure dependent model parameters and associated compressibility coefficients, and highly nonlinear apparent convective flux (velocity) and apparent diffusivity. An important application is to the determination of shale rock properties, such as porosity...

  5. Combined Estimation of Hydrogeologic Conceptual Model, Parameter, and Scenario Uncertainty with Application to Uranium Transport at the Hanford Site 300 Area

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Philip D.; Ye, Ming; Rockhold, Mark L.; Neuman, Shlomo P.; Cantrell, Kirk J.

    2007-07-30

    This report to the Nuclear Regulatory Commission (NRC) describes the development and application of a methodology to systematically and quantitatively assess predictive uncertainty in groundwater flow and transport modeling that considers the combined impact of hydrogeologic uncertainties associated with the conceptual-mathematical basis of a model, model parameters, and the scenario to which the model is applied. The methodology is based on a n extension of a Maximum Likelihood implementation of Bayesian Model Averaging. Model uncertainty is represented by postulating a discrete set of alternative conceptual models for a site with associated prior model probabilities that reflect a belief about the relative plausibility of each model based on its apparent consistency with available knowledge and data. Posterior model probabilities are computed and parameter uncertainty is estimated by calibrating each model to observed system behavior; prior parameter estimates are optionally included. Scenario uncertainty is represented as a discrete set of alternative future conditions affecting boundary conditions, source/sink terms, or other aspects of the models, with associated prior scenario probabilities. A joint assessment of uncertainty results from combining model predictions computed under each scenario using as weight the posterior model and prior scenario probabilities. The uncertainty methodology was applied to modeling of groundwater flow and uranium transport at the Hanford Site 300 Area. Eight alternative models representing uncertainty in the hydrogeologic and geochemical properties as well as the temporal variability were considered. Two scenarios represent alternative future behavior of the Columbia River adjacent to the site were considered. The scenario alternatives were implemented in the models through the boundary conditions. Results demonstrate the feasibility of applying a comprehensive uncertainty assessment to large-scale, detailed groundwater flow

  6. BIOPROTA Key Issues in Biosphere Aspects of Assessment of the Long-term Impact of Contaminant Releases Associated with Radioactive Waste Management Theme 2: Task 7:Modelling Processes in the Geosphere Biosphere Interface Zone

    Energy Technology Data Exchange (ETDEWEB)

    Pinedo, P.; Smith, G.; Aguero, A.; Albrecht, A.; Bath, A.; Benhabderrahmane, H.; Van Dorp, F.; Kautsky, U.; Klos, R.; Laciok, A.; Milodowski, T.; Selroos, J.O.; Simon, I.; Texier, D.; Thorne, M.; Willans, M.

    2005-07-01

    This document reports on BIOPROTA Theme 2, task 7 which investigated modelling processes in the geosphere- biosphere interface zone (GBIZ) during performance assessments. Modelling issues in the treatment of the GBIZ are identified. A large proportion of the identified issues concern modelling radionuclide behaviour in near surface aquifers which are subject to relatively high gradients in chemical and other conditions. Other key issues concern transfer of radionuclides through the unsaturated zone above aquifers, bearing in mind the scope for erosion and variations in the level of the phreatic surface and also the consideration of environmental change. A number of research areas are highlighted that are aimed at addressing each of the identified issues in the treatment of GBIZ. These include (i) Developing of a current statement of continuing problems, and hence clarify and justify the need to do more; (ii) Conducting a review of site investigations as they have been done already, and determine whether they meet performance assessment requirements; (iii) Identifying scenarios and FEPs considered in current treatments; and, (iv) Conducting source-pathway-receptor analysis to demonstrate comprehensiveness of the overall scenario identification process. The objectives of these activities would be to determine the potential to reduce uncertainties and/or conservative assumptions in assessment of radionuclide transfer from the geosphere to biosphere domains, taking account of environmental change; and to develop guidance on site-characterisation needs at different types of site, as regards the near-surface features. (Author) 23 refs.

  7. Importance of Physical and Physiological Parameters in Simulated Particle Transport in the Alveolar Zone of the Human Lung

    Directory of Open Access Journals (Sweden)

    Dogan Ciloglu

    2017-01-01

    Full Text Available The trajectory and deposition efficiency of micron-sized (1–5 µm particles, inhaled into the pulmonary system, are accurately determined with the aid of a newly developed model and modified simulation techniques. This alveolar model, which has a simple but physiologically appropriate geometry, and the utilized fluid structure interaction (FSI methods permit the precise simulation of tissue wall deformation and particle fluid interactions. The relation between tissue movement and airflow in the alveolated duct is solved by a two-way fluid structure interaction simulation technique, using ANSYS Workbench (Release 16.0, ANSYS INC., Pittsburgh, PA, USA, 2015. The dynamic transport of particles and their deposition are investigated as a function of aerodynamic particle size, tissue visco-elasticity, tidal breathing period, gravity orientation and particle–fluid interactions. It is found that the fluid flows and streamlines differ between the present flexible model and rigid models, and the two-way coupling particle trajectories vary relative to one-way particle coupling. In addition, the results indicate that modelling the two-way coupling particle system is important because the two-way discrete phase method (DPM approach despite its complexity provides more extensive particle interactions and is more reliable than transport results from the one-way DPM approach. The substantial difference between the results of the two approaches is likely due to particle–fluid interactions, which re-suspend the sediment particles in the airway stream and hence pass from the current generation.

  8. Parameters measurement transport hydrogen in Fe alloys with low contents of C through the technique of permeation; Medida de los Parametros de Transporte de Hidrogeno en Aleaciones de Fe con Bajo Contenidos de C mediante la Tecnica de Permeacion

    Energy Technology Data Exchange (ETDEWEB)

    Penalva, I.; Alberro, G.; Legarda, F.; Vila, R.; Ortiz, C. J.

    2012-07-01

    The characterization of the candidates materials to be part of a fusion reactor implies interaction with hydrogen isotopes. Their transport parameters will affect the inventory of hydrogen retained in components of the fusion reactor and permeation of these isotopes through the materials structure can affect areas of human work. Therefore, the analysis of any concept related to fusion reactors, the plasma stability or radiation safety, lies in the knowledge of these parameters. The main objective of this work was to determine the influence of the C content of the iron alloys in the transport parameters of hydrogen using the technique of permeation. Six samples were analyzed experimentally by EFDA (European Fusion Development Agreement) with microstructure and chemical content of alloys controlled. Three of them, Fe pure, FeP y Fe10%Cr, contained insignificant amounts of C, while the other three, FeC, FePC y Fe10%CrC, had the same metallurgical composition as its corresponding pair, with the exception of the content of C.

  9. Release History and Transport Parameters of Relativistic Solar Electrons Inferred From Near-the-Sun In Situ Observations

    Science.gov (United States)

    Agueda, N.; Lario, D.

    2016-10-01

    We study four consecutive 300-800 keV electron events observed on 1980 May 28 by Helios-1, when the spacecraft was located at 0.31 au from the Sun. We use two different techniques to extract the release time history of electrons at the Sun: (1) a data-driven method based on the assumption that particles conserve their magnetic moment as they propagate between the Sun and the spacecraft and (2) an inversion method that utilizes particle transport simulation results. Both methods make use of the particle angular distributions measured relative to the local direction of the magnetic field. The general characteristics of the release time profiles obtained by these two techniques are similar, especially during their rising phases. We find indications that the strength of the interplanetary scattering varies with the size of the solar parent event, suggesting that scattering processes are not necessarily an inherent property of the medium but are related to the amount of released particles at the Sun. We use the inferred release profiles to compute the expected intensities at 1 au. In contrast to simultaneous near-Earth observations by the Interplanetary Monitoring Platform (IMP-8), our simulations predict the observation of four separate events at 1 au. Processes that could contribute to the observation of one single time-extended event at 1 au include (1) distinct magnetic connections of the spacecraft to the particle sources, (2) the spatio-temporal evolution of the particle sources, and (3) different particle transport conditions, including a variation of {λ }r with radial distance and/or heliolongitude, as well as the possibility that electrons reached IMP-8 by diffusion perpendicular to the interplanetary magnetic field.

  10. A coupled transport and solid mechanics formulation with improved reaction kinetics parameters for modeling oxidation and decomposition in a uranium hydride bed.

    Energy Technology Data Exchange (ETDEWEB)

    Salloum, Maher N.; Shugard, Andrew D.; Kanouff, Michael P.; Gharagozloo, Patricia E.

    2013-03-01

    Modeling of reacting flows in porous media has become particularly important with the increased interest in hydrogen solid-storage beds. An advanced type of storage bed has been proposed that utilizes oxidation of uranium hydride to heat and decompose the hydride, releasing the hydrogen. To reduce the cost and time required to develop these systems experimentally, a valid computational model is required that simulates the reaction of uranium hydride and oxygen gas in a hydrogen storage bed using multiphysics finite element modeling. This SAND report discusses the advancements made in FY12 (since our last SAND report SAND2011-6939) to the model developed as a part of an ASC-P&EM project to address the shortcomings of the previous model. The model considers chemical reactions, heat transport, and mass transport within a hydride bed. Previously, the time-varying permeability and porosity were considered uniform. This led to discrepancies between the simulated results and experimental measurements. In this work, the effects of non-uniform changes in permeability and porosity due to phase and thermal expansion are accounted for. These expansions result in mechanical stresses that lead to bed deformation. To describe this, a simplified solid mechanics model for the local variation of permeability and porosity as a function of the local bed deformation is developed. By using this solid mechanics model, the agreement between our reacting bed model and the experimental data is improved. Additionally, more accurate uranium hydride oxidation kinetics parameters are obtained by fitting the experimental results from a pure uranium hydride oxidation measurement to the ones obtained from the coupled transport-solid mechanics model. Finally, the coupled transport-solid mechanics model governing equations and boundary conditions are summarized and recommendations are made for further development of ARIA and other Sandia codes in order for them to sufficiently implement the model.

  11. Chamber transport

    Energy Technology Data Exchange (ETDEWEB)

    OLSON,CRAIG L.

    2000-05-17

    Heavy ion beam transport through the containment chamber plays a crucial role in all heavy ion fusion (HIF) scenarios. Here, several parameters are used to characterize the operating space for HIF beams; transport modes are assessed in relation to evolving target/accelerator requirements; results of recent relevant experiments and simulations of HIF transport are summarized; and relevant instabilities are reviewed. All transport options still exist, including (1) vacuum ballistic transport, (2) neutralized ballistic transport, and (3) channel-like transport. Presently, the European HIF program favors vacuum ballistic transport, while the US HIF program favors neutralized ballistic transport with channel-like transport as an alternate approach. Further transport research is needed to clearly guide selection of the most attractive, integrated HIF system.

  12. A new multimedia contaminant fate model for China: how important are environmental parameters in influencing chemical persistence and long-range transport potential?

    Science.gov (United States)

    Zhu, Ying; Price, Oliver R; Tao, Shu; Jones, Kevin C; Sweetman, Andy J

    2014-08-01

    We present a new multimedia chemical fate model (SESAMe) which was developed to assess chemical fate and behaviour across China. We apply the model to quantify the influence of environmental parameters on chemical overall persistence (POV) and long-range transport potential (LRTP) in China, which has extreme diversity in environmental conditions. Sobol sensitivity analysis was used to identify the relative importance of input parameters. Physicochemical properties were identified as more influential than environmental parameters on model output. Interactive effects of environmental parameters on POV and LRTP occur mainly in combination with chemical properties. Hypothetical chemicals and emission data were used to model POV and LRTP for neutral and acidic chemicals with different KOW/DOW, vapour pressure and pKa under different precipitation, wind speed, temperature and soil organic carbon contents (fOC). Generally for POV, precipitation was more influential than the other environmental parameters, whilst temperature and wind speed did not contribute significantly to POV variation; for LRTP, wind speed was more influential than the other environmental parameters, whilst the effects of other environmental parameters relied on specific chemical properties. fOC had a slight effect on POV and LRTP, and higher fOC always increased POV and decreased LRTP. Example case studies were performed on real test chemicals using SESAMe to explore the spatial variability of model output and how environmental properties affect POV and LRTP. Dibenzofuran released to multiple media had higher POV in northwest of Xinjiang, part of Gansu, northeast of Inner Mongolia, Heilongjiang and Jilin. Benzo[a]pyrene released to the air had higher LRTP in south Xinjiang and west Inner Mongolia, whilst acenaphthene had higher LRTP in Tibet and west Inner Mongolia. TCS released into water had higher LRTP in Yellow River and Yangtze River catchments. The initial case studies demonstrated that SESAMe

  13. Charge transport in zirconium doped anatase nanowires dye-sensitized solar cells: Trade-off between lattice strain and photovoltaic parameters

    Energy Technology Data Exchange (ETDEWEB)

    Archana, P. S.; Gupta, Arunava [Department of Chemistry, University of Alabama, 250 Hackberry Lane, Shelby hall, Tuscaloosa 35401 Alabama (United States); Yusoff, Mashitah M.; Jose, Rajan, E-mail: rjose@ump.edu.my [Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang, 26300 Kuantan (Malaysia)

    2014-10-13

    Zirconium (Zr) is doped up to 5 at. % in anatase TiO{sub 2} nanowires by electrospinning and used as working electrode in dye-sensitized solar cells. Variations observed in the photovoltaic parameters were correlated by electrochemical impedance spectroscopy, open circuit voltage decay, and X-ray diffraction measurements. Results show that homovalent substitution of Zr in TiO{sub 2} increased the chemical capacitance and electron diffusion coefficient which in turn decreased charge transport resistance and charge transit time. However, lattice strain due to size mismatch between the Zr{sup 4+} and Ti{sup 4+} ions decreased open circuit voltage and fill factor thereby setting a trade-off between doping concentration and photovoltaic properties.

  14. Atrazine dissipation in s-triazine-adapted and nonadapted soil from Colorado and Mississippi: implications of enhanced degradation on atrazine fate and transport parameters.

    Science.gov (United States)

    Krutz, L Jason; Shaner, Dale L; Accinelli, Cesare; Zablotowicz, Robert M; Henry, W Brien

    2008-01-01

    Soil bacteria have developed novel metabolic abilities resulting in enhanced atrazine degradation. Consequently, there is a need to evaluate the effects of enhanced degradation on parameters used to model atrazine fate and transport. The objectives of this study were (i) to screen Colorado (CO) and Mississippi (MS) atrazine-adapted and non-adapted soil for genes that code for enzymes able to rapidly catabolize atrazine and (ii) to compare atrazine persistence, Q(10), beta, and metabolite profiles between adapted and non-adapted soils. The atzABC and/or trzN genes were detected only in adapted soil. Atrazine's average half-life in adapted soil was 10-fold lower than that of the non-adapted soil and 18-fold lower than the USEPA estimate of 3 to 4 mo. Q(10) was greater in adapted soil. No difference in beta was observed between soils. The accumulation and persistence of mono-N-dealkylated metabolites was lower in adapted soil; conversely, under suboptimal moisture levels in CO adapted soil, hydroxyatrazine concentrations exceeded 30% of the parent compounds' initial mass. Results indicate that (i) enhanced atrazine degradation and atzABC and/or trzN genes are likely widespread across the Western and Southern corn-growing regions of the USA; (ii) persistence of atrazine and its mono-N-dealkylated metabolites is significantly reduced in adapted soil; (iii) hydroxyatrazine can be a major degradation product in adapted soil; and (iv) fate, transport, and risk assessment models that assume historic atrazine degradation pathways and persistence estimates will likely overpredict the compounds' transport potential in adapted soil.

  15. Kinetic parameters, collision rates, energy exchanges and transport coefficients of non-thermal electrons in premixed flames at sub-breakdown electric field strengths

    Science.gov (United States)

    Bisetti, Fabrizio; El Morsli, Mbark

    2014-01-01

    The effects of an electric field on the collision rates, energy exchanges and transport properties of electrons in premixed flames are investigated via solutions to the Boltzmann kinetic equation. The case of high electric field strength, which results in high-energy, non-thermal electrons, is analysed in detail at sub-breakdown conditions. The rates of inelastic collisions and the energy exchange between electrons and neutrals in the reaction zone of the flame are characterised quantitatively. The analysis includes attachment, ionisation, impact dissociation, and vibrational and electronic excitation processes. Our results suggest that Townsend breakdown occurs for E/N = 140 Td. Vibrational excitation is the dominant process up to breakdown, despite important rates of electronic excitation of CO, CO2 and N2 as well as impact dissociation of O2 being apparent from 50 Td onwards. Ohmic heating in the reaction zone is found to be negligible (less than 2% of peak heat release rate) up to breakdown field strengths for realistic electron densities equal to 1010 cm-3. The observed trends are largely independent of equivalence ratio. In the non-thermal regime, electron transport coefficients are insensitive to mixture composition and approximately constant across the flame, but are highly dependent on the electric field strength. In the thermal limit, kinetic parameters and transport coefficients vary substantially across the flame due to the spatially inhomogeneous concentration of water vapour. A practical approach for identifying the plasma regime (thermal versus non-thermal) in studies of electric field effects on flames is proposed.

  16. Kinetic parameters, collision rates, energy exchanges and transport coefficients of non-thermal electrons in premixed flames at sub-breakdown electric field strengths

    KAUST Repository

    Bisetti, Fabrizio

    2014-01-02

    The effects of an electric field on the collision rates, energy exchanges and transport properties of electrons in premixed flames are investigated via solutions to the Boltzmann kinetic equation. The case of high electric field strength, which results in high-energy, non-thermal electrons, is analysed in detail at sub-breakdown conditions. The rates of inelastic collisions and the energy exchange between electrons and neutrals in the reaction zone of the flame are characterised quantitatively. The analysis includes attachment, ionisation, impact dissociation, and vibrational and electronic excitation processes. Our results suggest that Townsend breakdown occurs for E/N = 140 Td. Vibrational excitation is the dominant process up to breakdown, despite important rates of electronic excitation of CO, CO2 and N2 as well as impact dissociation of O2 being apparent from 50 Td onwards. Ohmic heating in the reaction zone is found to be negligible (less than 2% of peak heat release rate) up to breakdown field strengths for realistic electron densities equal to 1010 cm-3. The observed trends are largely independent of equivalence ratio. In the non-thermal regime, electron transport coefficients are insensitive to mixture composition and approximately constant across the flame, but are highly dependent on the electric field strength. In the thermal limit, kinetic parameters and transport coefficients vary substantially across the flame due to the spatially inhomogeneous concentration of water vapour. A practical approach for identifying the plasma regime (thermal versus non-thermal) in studies of electric field effects on flames is proposed. © 2014 Taylor & Francis.

  17. Sorbing tracer experiments in a crystalline rock fracture at Äspö (Sweden): 2. Transport model and effective parameter estimation

    Science.gov (United States)

    Cvetkovic, V.; Cheng, H.; Widestrand, H.; ByegâRd, J.; Winberg, A.; Andersson, P.

    2007-11-01

    Transport and retention of sorbing tracers in a single, altered crystalline rock fracture on a 5 m scale is investigated. We evaluate the results of a comprehensive field study (referred to as Tracer Retention Understanding Experiments, first phase (TRUE-1)), at a 400 m depth of the Äspö Hard Rock Laboratory (Sweden). A total of 16 breakthrough curves are analyzed, from three test configurations using six radioactive tracers with a broad range of sorption properties. A transport-retention model is proposed, and its applicability is assessed based on available data. We find that the conventional model with an asymptotic power law slope of -3/2 (one-dimensional diffusion into an unlimited rock matrix) is a reasonable approximation for the conditions of the TRUE-1 tests. Retention in the altered rock of the rim zone appears to be significantly stronger than implied by retention properties inferred from generic (unaltered) rock samples. The effective physical parameters which control retention (matrix porosity and retention aperture) are comparable for all three test configurations. The most plausible in situ (rim zone) porosity is in the range 1%-2%, which constrains the effective retention aperture to the range 0.2-0.7 mm. For all sorbing tracers the estimated in situ sorption coefficient appears to be larger by at least a factor of 10, compared to the value inferred from through-diffusion tests using unaltered rock samples.

  18. Growth curves and age-related changes in carcass characteristics, organs, serum parameters, and intestinal transporter gene expression in domestic pigeon (Columba livia).

    Science.gov (United States)

    Gao, C Q; Yang, J X; Chen, M X; Yan, H C; Wang, X Q

    2016-04-01

    Two experiments were conducted to fit growth curves, and determine age-related changes in carcass characteristics, organs, serum biochemical parameters, and gene expression of intestinal nutrient transporters in domestic pigeon (Columba livia). In experiment 1, body weight (BW) of 30 pigeons was respectively determined at 1, 3, 7, 14, 21, 28, and 35 days old to fit growth curves and to describe the growth of pigeons. In experiment 2, eighty-four 1-day-old squabs were grouped by weight into 7 groups. On d 1, 3, 7, 14, 21, 28, and 35, twelve birds from each group were randomly selected for slaughter and post-slaughter analysis. The results showed that BW of pigeons increased rapidly from d 1 to d 28 (a 25.7-fold increase), and then had little change until d 35. The Logistic, Gompertz, and Von Bertalanffy functions can all be well fitted with the growth curve of domestic pigeons (R2>0.90) and the Gompertz model showed the highest R2value among the models (R2=0.9997). The equation of Gompertz model was Y=507.72×e-(3.76exp(-0.17t))(Y=BW of pigeon (g); t=time (day)). In addition, breast meat yield (%) increased with age throughout the experiment, whereas the leg meat yield (%) reached to the peak on d 14. Serum total protein, albumin, globulin, and glucose concentration were increased with age, whereas serum uric acid concentration was decreased (P<0.05). Furthermore, the gene expressions of nutrient transporters (y+LAT2, LAT1, B0AT1, PepT1, and NHE2) in jejunum of pigeon were increased with age. The results of correlation analysis showed the gene expressions of B0AT1, PepT1, and NHE2 had positive correlations with BW (0.73transporters in small intestine might cause the differences in their development patterns.

  19. Changes in heliophysical parameter influence on environment of the Earth

    Science.gov (United States)

    Mukherjee, S.; Ma, W.

    2007-12-01

    Terrestrial as well as extraterrestrial satellite data and environmental parameter records were correlated. It has been observed that some relationship exists in between the changes in environment and extraterrestrial phenomenon. The star flare changes the cosmic parameters. The nearest star of earth, the Sun, is found to be under the influence of the star flare. It has been observed that there is some relationship in between the planetary indices (Kp) Electron flux (E flux) Proton flux (P-flux) of Sun-Earth environment with the changes in thermosphere, ionosphere, atmosphere and geosphere. The tsunami of 26 December 2004, abnormal snowfall in 2004-2005, sudden hike in global temperature and erratic monsoon in India and irregular rainfall in other parts of the world in 2006-2007 followed by snowfall and torrential rain are the impact of the star-sun-earth relationship.

  20. Characterization of rPEPT2-mediated Gly-Sar transport parameters in the rat kidney proximal tubule cell line SKPT-0193 cl.2 cultured in basic growth media

    DEFF Research Database (Denmark)

    Bravo, Silvina A; Nielsen, Carsten Uhd; Frokjaer, Sven;

    2005-01-01

    added. The aim of the study was thus to characterize Gly-Sar transport parameters in SKPT cells cultured in basic growth media (conventional media without added agonists). Morphology was studied using confocal laser scanning microscopy (CLSM) and immunohistochemistry. Monolayer integrity was evaluated......The rat proximal kidney tubule cell line SKPT-0193 cl.2 (SKPT) expresses the di-/tripeptide transporter PEPT2 (rPEPT2) and has been used to study PEPT2-mediated transport. Traditionally, SKPT cells have been cultured in growth media supplemented with epidermal growth factor (EGF), apotransferrin...

  1. Influencing parameters of water and methanol transport in a big direct methanol fuel cell; Einflussgroessen auf den Wasser- und Methanoltransport einer groesseren Direkt-Methanol Brennstoffzelle

    Energy Technology Data Exchange (ETDEWEB)

    Schonert, Morten

    2008-07-01

    The author investigated the influencing parameters of water and methanol transport in a big direct methanol fuel cell (Pel > 1 kW) with the intention of making the direct methanol fuel cell system water-autonomous. As water is consumed during the electrochemical reaction on the anode while more water is produced on the cathode, the difference must be removed via the air. Any further water produced on the cathode must be condensed and recirculated to the anode. With increasing ambient temperature, the air volume flow must be reduced because otherwise more water would be removed than is acceptable. Low air volume flow on the cathode causes unstable cell voltage, which is also assumed to be caused by excess water production. For this reason, an attempt was made to prevent excess water production on the cathode by a system engineering approach. It was found that at the low air volume flow required for water autonomy, water permeation through the membrane-electrode aggregate (MEA) depends on the uptake capacity and on the time of residue of air over the cathode and less on the cathode material. Water permeation stops when the concentration gradient is balanced. Apart from the water permeation, there is also water transport through the Nafion {sup registered} membrane, i.e. so-called electroosmotic drag (ESD). This is an active transport mechanism that can also work against a concentration gradient. It could be shown that the EOD can be reduced by using water-impermeable materials for the gas diffusion layer on the anode. This will reduce the water volume that reaches the membrane, i.e. the water on the cathode. On the other hand, there was no measurable effect of the cathode design on water or methanol transport. The electrochemical performance of the membrane-electrode units under investigation was robust in case of many influencing parameters, e.g. dispersion, the conditions of MEA fabrication by hot pressing, themembrane thickness and the rate of methanol permeation

  2. Contaminant transport in fracture networks with heterogeneous rock matrices. The Picnic code

    Energy Technology Data Exchange (ETDEWEB)

    Barten, Werner [Paul Scherrer Inst., CH-5232 Villigen PSI (Switzerland); Robinson, Peter C. [QuantiSci Limited, Henley-on-Thames (United Kingdom)

    2001-02-01

    In the context of safety assessment of radioactive waste repositories, complex radionuclide transport models covering key safety-relevant processes play a major role. In recent Swiss safety assessments, such as Kristallin-I, an important drawback was the limitation in geosphere modelling capability to account for geosphere heterogeneities. In marked contrast to this limitation in modelling capabilities, great effort has been put into investigating the heterogeneity of the geosphere as it impacts on hydrology. Structural geological methods have been used to look at the geometry of the flow paths on a small scale and the diffusion and sorption properties of different rock materials have been investigated. This huge amount of information could however be only partially applied in geosphere transport modelling. To make use of these investigations the 'PICNIC project' was established as a joint cooperation of PSI/Nagra and QuantiSci to provide a new geosphere transport model for Swiss safety assessment of radioactive waste repositories. The new transport code, PICNIC, can treat all processes considered in the older geosphere model RANCH MD generally used in the Kristallin-I study and, in addition, explicitly accounts for the heterogeneity of the geosphere on different spatial scales. The effects and transport phenomena that can be accounted for by PICNIC are a combination of (advective) macro-dispersion due to transport in a network of conduits (legs), micro-dispersion in single legs, one-dimensional or two-dimensional matrix diffusion into a wide range of homogeneous and heterogeneous rock matrix geometries, linear sorption of nuclides in the flow path and the rock matrix and radioactive decay and ingrowth in the case of nuclide chains. Analytical and numerical Laplace transformation methods are integrated in a newly developed hierarchical linear response concept to efficiently account for the transport mechanisms considered which typically act on extremely

  3. DOC Affinity as a Key Parameter for Explaining the Transport Patterns of U, Th and Other Elements in the Boreal Landscape

    Science.gov (United States)

    Lidman, F.; Köhler, S.; Björkvald, L.; Mörth, M.; Laudon, H.

    2009-04-01

    used to estimate the percentage of each element bound to DOC in these waters and this shows a strong correlation to how elements are affected by wetlands/lakes in the catchments. Experiments, e.g. using flow field-flow fractionation, in the Krycklan Catchment have demonstrated that DOC is important for many elements in the transport from soils to streams, and as it appears these processes will also have an impact on the catchment scale. The general picture is that the variation between sub-catchments is small for elements that do not bind strongly to DOC, while there is a considerable and systematic variation for elements with a high DOC affinity. This suggests that DOC affinity is a key parameter for understanding the fate and transport patters for elements in the boreal region. The results could also be used to predict the long-term fate of artificial elements from nuclear waste such as neptunium, plutonium or americium, since it relates fundamental biogeochemical processes to patterns on the catchment scale.

  4. TORT solutions to the NEA suite of benchmarks for 3D transport methods and codes over a range in parameter space

    Energy Technology Data Exchange (ETDEWEB)

    Bekar, Kursat B. [Department of Mechanical and Nuclear Engineering, Penn State University, University Park, PA 16802 (United States)], E-mail: bekarkb@ornl.gov; Azmy, Yousry Y. [Department of Nuclear Engineering, North Carolina State University, Raleigh, NC 27695 (United States)], E-mail: yyazmy@ncsu.edu

    2009-04-15

    We present the TORT solutions to the 3D transport codes' suite of benchmarks exercise. An overview of benchmark configurations is provided, followed by a description of the TORT computational model we developed to solve the cases comprising the benchmark suite. In the numerical experiments reported in this paper, we chose to refine the spatial and angular discretizations simultaneously, from the coarsest model (40 x 40 x 40, 200 angles) to the finest model (160 x 160 x 160, 800 angles). The MCNP reference solution is used for evaluating the effect of model-refinement on the accuracy of the TORT solutions. The presented results show that the majority of benchmark quantities are computed with good accuracy by TORT, and that the accuracy improves with model refinement. However, this deliberately severe test has exposed some deficiencies in both deterministic and stochastic solution approaches. Specifically, TORT fails to converge the inner iterations in some benchmark configurations while MCNP produces zero tallies, or drastically poor statistics for some benchmark quantities. We conjecture that TORT's failure to converge is driven by ray effects in configurations with low scattering ratio and/or highly skewed computational cells, i.e. aspect ratio far from unity. The failure of MCNP occurs in quantities tallied over a very small area or volume in physical space, or quantities tallied many ({approx}25) mean free paths away from the source. Hence automated, robust, and reliable variance reduction techniques are essential for obtaining high quality reference values of the benchmark quantities. Preliminary results of the benchmark exercise indicate that the occasionally poor performance of TORT is shared with other deterministic codes. Armed with this information, method developers can now direct their attention to regions in parameter space where such failures occur and design alternative solution approaches for such instances.

  5. Identification of TCE and PCE sorption and biodegradation parameters in a sandy aquifer for fate and transport modelling: batch and column studies.

    Science.gov (United States)

    Kret, E; Kiecak, A; Malina, G; Nijenhuis, I; Postawa, A

    2015-07-01

    The main aim of this study was to determine the sorption and biodegradation parameters of trichloroethene (TCE) and tetrachloroethene (PCE) as input data required for their fate and transport modelling in a Quaternary sandy aquifer. Sorption was determined based on batch and column experiments, while biodegradation was investigated using the compound-specific isotope analysis (CSIA). The aquifer materials medium (soil 1) to fine (soil 2) sands and groundwater samples came from the representative profile of the contaminated site (south-east Poland). The sorption isotherms were approximately linear (TCE, soil 1, K d = 0.0016; PCE, soil 1, K d = 0.0051; PCE, soil 2, K d = 0.0069) except for one case in which the best fitting was for the Langmuir isotherm (TCE, soil 2, K f = 0.6493 and S max = 0.0145). The results indicate low retardation coefficients (R) of TCE and PCE; however, somewhat lower values were obtained in batch compared to column experiments. In the column experiments with the presence of both contaminants, TCE influenced sorption of PCE, so that the R values for both compounds were almost two times higher. Non-significant differences in isotope compositions of TCE and PCE measured in the observation points (δ(13)C values within the range of -23.6 ÷ -24.3‰ and -26.3 ÷-27.7‰, respectively) indicate that biodegradation apparently is not an important process contributing to the natural attenuation of these contaminants in the studied sandy aquifer.

  6. Optimization of deterministic transport parameters for the calculation of the dose distribution around a high dose-rate 192Ir brachytherapy source.

    Science.gov (United States)

    Gifford, Kent A; Price, Michael J; Horton, John L; Wareing, Todd A; Mourtada, Firas

    2008-06-01

    The goal of this work was to calculate the dose distribution around a high dose-rate 192Ir brachytherapy source using a multi-group discrete ordinates code and then to compare the results with a Monte Carlo calculated dose distribution. The unstructured tetrahedral mesh discrete ordinates code Attila version 6.1.1 was used to calculate the photon kerma rate distribution in water around the Nucletron microSelectron mHDRv2 source. MCNPX 2.5.c was used to compute the Monte Carlo water photon kerma rate distribution. Two hundred million histories were simulated, resulting in standard errors of the mean of less than 3% overall. The number of energy groups, S(n) (angular order), P(n) (scattering order), and mesh elements were varied in addition to the method of analytic ray tracing to assess their effects on the deterministic solution. Water photon kerma rate matrices were exported from both codes into an in-house data analysis software. This software quantified the percent dose difference distribution, the number of points within +/- 3% and +/- 5%, and the mean percent difference between the two codes. The data demonstrated that a 5 energy-group cross-section set calculated results to within 0.5% of a 15 group cross-section set. S12 was sufficient to resolve the solution in angle. P2 expansion of the scattering cross-section was necessary to compute accurate distributions. A computational mesh with 55 064 tetrahedral elements in a 30 cm diameter phantom resolved the solution spatially. An efficiency factor of 110 with the above parameters was realized in comparison to MC methods. The Attila code provided an accurate and efficient solution of the Boltzmann transport equation for the mHDRv2 source.

  7. IN SITU BIOREMEDIATION OF TRICHLOROETHYLENE USING BURKHOLDERIA CEPACIA G4 PR1: ANALYSIS OF TRANSPORT PARAMETERS FOR RISK ASSESSMENT (RESEARCH BRIEF)

    Science.gov (United States)

    Transport of bacteria through geologic media may be viewed as being governed by sorption-desorption reactions. In this investigation, four facets of the process were examined: (I) the impact of sorption on bacterial transport under typical ground water flow velocities and a diffe...

  8. In-depth evaluation of Gly-Sar transport parameters as a function of culture time in the Caco-2 cell model

    DEFF Research Database (Denmark)

    Bravo, Silvina A.; Nielsen, Carsten Uhd; Amstrup, Jan

    2004-01-01

    The aim of the present study was to investigate the influence of culture time on hPEPT1-mediated transport in Caco-2 cell monolayers. Peptide transport activity in Caco-2 cells grown in standard media and in a "rapid" 4-day model was first compared. The rapid 4-day Caco-2 cell model, cultured using...... a cocktail of growth factors and agonists, displayed lower peptide uptake capacity than Caco-2 cells grown for 4 days in conventional media, and was judged to be unsuitable for peptide transport studies. Peptide transport activity as well as monolayer integrity and tissue morphology were evaluated...... in the standard >21 days model as a function of the culture time. Peptide transport activity was studied using [14C]-glycylsarcosine ([ 14C]-Gly-Sar). Monolayer integrity was evaluated by transepithelial electrical resistance (TEER) measurements and [3H]-mannitol permeabilities. Tissue morphology and hPEPT1...

  9. Phase I Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 99: Rainier Mesa/Shoshone Mountain, Nevada Test Site, Nye County, Nevada, Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Nathan Bryant

    2008-05-01

    This document presents a summary and framework of available transport data and other information directly relevant to the development of the Rainier Mesa/Shoshone Mountain (RMSM) Corrective Action Unit (CAU) 99 groundwater transport model. Where appropriate, data and information documented elsewhere are briefly summarized with reference to the complete documentation.

  10. Intestinal transporters for endogenic and pharmaceutical organic anions: The challenges of deriving in-vitro kinetic parameters for the prediction of clinically relevant drug-drug interactions

    DEFF Research Database (Denmark)

    Grandvuinet, Anne Sophie; Vestergaard, Henrik Tang; Rapin, Nicolas

    2012-01-01

    Objectives This review provides an overview of intestinal human transporters for organic anions and stresses the need for standardization of the various in-vitro methods presently employed in drug-drug interaction (DDI) investigations. Key findings Current knowledge on the intestinal expression o...... the involvement of other transporters than P-glycoprotein. Moreover, the interplay between various processes that a drug is subject to in-vivo such as translocation by several transporters and dissolution should be considered. © 2012 Royal Pharmaceutical Society....

  11. Transport of Escherichia coli bacteria through laboratory columns of glacial-outwash sediments: estimating model parameter values based on sediment characteristics.

    Science.gov (United States)

    Levy, J; Sun, K; Findlay, R H; Farruggia, F T; Porter, J; Mumy, K L; Tomaras, J; Tomaras, A

    2007-01-05

    Bacterial transport through cores of intact, glacial-outwash aquifer sediment was investigated with the overall goal of better understanding bacterial transport and developing a predictive capability based on the sediment characteristics. Variability was great among the cores. Normalized maximum bacterial-effluent concentrations ranged from 5.4x10(-7) to 0.36 and effluent recovery ranged from 2.9x10(-4) to 59%. Bacterial breakthrough was generally rapid with a sharp peak occurring nearly twice as early as the bromide peak. Bacterial breakthrough exhibited a long tail of relatively constant concentration averaging three orders of magnitude less than the peak concentration for up to 32 pore volumes. The tails were consistent with non-equilibrium detachment, corroborated by the results of flow interruption experiments. Bacterial breakthrough was accurately simulated with a transport model incorporating advection, dispersion and first-order non-equilibrium attachment/detachment. Relationships among bacterial transport and sediment characteristics were explored with multiple regression analyses. These analyses indicated that for these cores and experimental conditions, easily-measurable sediment characteristics--median grain size, degree of sorting, organic-matter content and hydraulic conductivity--accounted for 66%, 61% and 89% of the core-to-core variability in the bacterial effective porosity, dispersivity and attachment-rate coefficient, respectively. In addition, the bacterial effective porosity, median grain size and organic-matter content accounted for 76% of the inter-core variability in the detachment-rate coefficient. The resulting regression equations allow prediction of bacterial transport based on sediment characteristics and are a possible alternative to using colloid-filtration theory. Colloid-filtration theory, used without the benefit of running bacterial transport experiments, did not as accurately replicate the observed variability in the attachment

  12. Mass Extinctions and Biosphere-Geosphere Stability

    Science.gov (United States)

    Rothman, Daniel; Bowring, Samuel

    2015-04-01

    Five times in the past 500 million years, mass extinctions have resulted in the loss of greater than three-fourths of living species. Each of these events is associated with significant environmental change recorded in the carbon-isotopic composition of sedimentary rocks. There are also many such environmental events in the geologic record that are not associated with mass extinctions. What makes them different? Two factors appear important: the size of the environmental perturbation, and the time scale over which it occurs. We show that the natural perturbations of Earth's carbon cycle during the past 500 million years exhibit a characteristic rate of change over two orders of magnitude in time scale. This characteristic rate is consistent with the maximum rate that limits quasistatic (i.e., near steady-state) evolution of the carbon cycle. We identify this rate with marginal stability, and show that mass extinctions occur on the fast, unstable side of the stability boundary. These results suggest that the great extinction events of the geologic past, and potentially a "sixth extinction" associated with modern environmental change, are characterized by common mechanisms of instability.

  13. Effects of contact resistance on the evaluation of charge carrier mobilities and transport parameters in amorphous zinc tin oxide thin-film transistors

    Science.gov (United States)

    Schulz, Leander; Yun, Eui-Jung; Dodabalapur, Ananth

    2014-06-01

    Accurate determination of the charge transport characteristics of amorphous metal-oxide transistors requires the mitigation of the effects of contact resistance. The use of additional electrodes as voltage probes can overcome contact resistance-related limitations and yields accurate charge carrier mobility values, trap depths and temperature and carrier density dependencies of mobility as well as trap depths. We show that large differences in measured charge carrier mobility values are obtained when such contact resistances are not factored out. Upon exclusion of the contact resistance, the true temperature dependence of charge carrier mobility appears in the form of two clearly distinct mobility regimes. Analyzing these revealed mobility regions leads to a more accurate determination of the underlying transport physics, which shows that contact resistance-related artefacts yield incorrect trends of trap depth with gate voltage, potentially leading to a misconstruction of the charge transport picture. Furthermore, a comparison of low- and high-mobility samples indicates that the observed effects are more general.

  14. A new modelling approach to simulate preferential flow and transport in water repellent porous media: Parameter sensitivity, and effects on crop growth and solute leaching

    NARCIS (Netherlands)

    Kramers, G.; Dam, van J.C.; Ritsema, C.J.; Stagnitti, F.; Oostindie, K.; Dekker, L.W.

    2005-01-01

    A modified version of the popular agrohydrological model SWAP has been used to evaluate modelling of soil water flow and crop growth at field situations in which water repellency causes preferential flow. The parameter sensitivity in such situations has been studied. Three options to model soil

  15. Revisiting the TORT Solutions to the NEA Suite of Benchmarks for 3D Transport Methods and Codes Over a Range in Parameter Space

    Energy Technology Data Exchange (ETDEWEB)

    Bekar, Kursat B [ORNL; Azmy, Yousry [North Carolina State University

    2009-01-01

    Improved TORT solutions to the 3D transport codes' suite of benchmarks exercise are presented in this study. Preliminary TORT solutions to this benchmark indicate that the majority of benchmark quantities for most benchmark cases are computed with good accuracy, and that accuracy improves with model refinement. However, TORT fails to compute accurate results for some benchmark cases with aspect ratios drastically different from 1, possibly due to ray effects. In this work, we employ the standard approach of splitting the solution to the transport equation into an uncollided flux and a fully collided flux via the code sequence GRTUNCL3D and TORT to mitigate ray effects. The results of this code sequence presented in this paper show that the accuracy of most benchmark cases improved substantially. Furthermore, the iterative convergence problems reported for the preliminary TORT solutions have been resolved by bringing the computational cells' aspect ratio closer to unity and, more importantly, by using 64-bit arithmetic precision in the calculation sequence. Results of this study are also reported.

  16. Modeling of radionuclide transport through rock formations and the resulting radiation exposure of reference persons. Calculations using Asse II parameters; Modellierung des Transports von Radionukliden durch Gesteinsschichten und der resultierenden Strahlenexposition von Referenzpersonen. Berechnungen mit Parametern der Asse II

    Energy Technology Data Exchange (ETDEWEB)

    Kueppers, Christian; Ustohalova, Veronika; Steinhoff, Mathias

    2012-05-21

    The long-term release of radioactivity into the ground water path cannot be excluded for the radioactive waste repository Asse II. The possible radiological consequences were analyzed using a radio-ecological scenario developed by GRS. A second scenario was developed considering the solubility of radionuclides in salt saturated solutions and retarding/retention effects during the radionuclide transport through the cap rock layers. The modeling of possible radiation exposure was based on the lifestyle habits of reference persons. In Germany the calculation procedure for the prediction of radionuclide release from final repositories is not defined by national standards, the used procedures are based on analogue methods from other radiation protection calculations.

  17. TORT Solutions to the NEA Suite of Benchmarks for 3D Transport Methods and Codes over a Range in Parameter Space

    Energy Technology Data Exchange (ETDEWEB)

    Bekar, Kursat B.; Azmy, Yousry Y. [Department of Mechanical and Nuclear Engineering, Penn State University, University Park, PA 16802 (United States)

    2008-07-01

    We present the TORT solutions to the 3-D transport codes' suite of benchmarks exercise. An overview of benchmark configurations is provided, followed by a description of the TORT computational model we developed to solve the cases comprising the benchmark suite. In the numerical experiments reported in this paper, we chose to refine the spatial and angular discretizations simultaneously, from the coarsest model (40x40x40, 200 angles) to the finest model (160x160x160, 800 angles), and employed the results of the finest computational model as reference values for evaluating the mesh-refinement effects. The presented results show that the solutions for most cases in the suite of benchmarks as computed by TORT are in the asymptotic regime. (authors)

  18. Complexity of Public Transport Networks

    Institute of Scientific and Technical Information of China (English)

    LU Huapu; SHI Ye

    2007-01-01

    The theory of complex networks was used to classify public transport networks into public transportation route networks, public transportation transfer networks, and bus station networks. The practical significance of the network parameters was then analyzed. The public transport networks in Langfang, Jining, and Dalian were then chosen as specific research cases. The results show that the public transportation networks have the characteristics of complex networks. In addition, the urban transportation network parameters all significantly affect the accessibility, convenience, and terrorist security capability of the urban public transportation network. The results link the findings with the actual situations to explore means to solve transportation system problems.

  19. Parameter Estimation

    DEFF Research Database (Denmark)

    2011-01-01

    of optimisation techniques coupled with dynamic solution of the underlying model. Linear and nonlinear approaches to parameter estimation are investigated. There is also the application of maximum likelihood principles in the estimation of parameters, as well as the use of orthogonal collocation to generate a set......In this chapter the importance of parameter estimation in model development is illustrated through various applications related to reaction systems. In particular, rate constants in a reaction system are obtained through parameter estimation methods. These approaches often require the application...... of algebraic equations as the basis for parameter estimation.These approaches are illustrated using estimations of kinetic constants from reaction system models....

  20. Numerical simulations of water flow and contaminants transport near mining wastes disposed in a fractured rock mass

    Institute of Scientific and Technical Information of China (English)

    Ben Abdelghani Farouk; Aubertin Michel; Simon Richard; Therrien René

    2015-01-01

    A numerical tool, called Hydro-Geosphere, was used to simulate unsaturated water flow and contami-nants migration around an open pit filled with mining wastes. Numerical simulations had been carried out to assess the influence of various factors on water flow and solute transport in and around the surface openings including recharge, properties of the waste material and presence of fractures in the surround-ing rock mass. The effect of the regional hydraulic gradient was also investigated. The analyses were con-ducted by simulating various 2D cases using experimentally obtained material properties and controlled boundary conditions. The effects of the hydrogeological properties of the filling material (i.e., water reten-tion curve and hydraulic conductivity function), fracture network characteristics and conductivity of the joints were assessed. The results illustrate that fractures control water flow and contaminants transport around the waste disposal area. A fracture network can desaturate the system and improve the regional gradient effect.

  1. INTRAVAL phase 2, test case 8. Alligator Rivers Natural Analogue. Modelling of uranium transport in the weathered zone at Koongarra, Australia

    Energy Technology Data Exchange (ETDEWEB)

    Hassanizadeh, S.M.; Van de Weerd, H.; Richardson-Van der Poel, M.A. [National Inst. of Public Health and Environmental Protection RIVM, Bilthoven (Netherlands)

    1993-01-01

    Preliminary results of modelling of the dispersion of uranium in the weathered and transition zones are given. In the course of the Alligator Rivers Analogue Project (ARAP) more insight was gained about the formation of the dispersion fan and about the hydrology at Koongarra. The here applied transport modelling strategy takes into account those results. First, a general explanation of Natural Analogue is given, next to a brief description of the ARAP test case, carried out within the INTRAVAL phase 2. INTRAVAL is an international project concerned with the use of mathematical models for predicting the potential transport of radioactive solutes in the geosphere. Following is the analysis of chemical data, necessary for the choice of the modelling approach, for estimation of model inputs and for testing model results. Subsequently, the modelling strategy is expounded and a description is given of METROPOL, the transport code, used for modelling. 11 figs., 2 tabs., 1 appendix, 17 refs.

  2. Assessment model validity document. NAMMU: A program for calculating groundwater flow and transport through porous media

    Energy Technology Data Exchange (ETDEWEB)

    Cliffe, K.A.; Morris, S.T.; Porter, J.D. [AEA Technology, Harwell (United Kingdom)

    1998-05-01

    NAMMU is a computer program for modelling groundwater flow and transport through porous media. This document provides an overview of the use of the program for geosphere modelling in performance assessment calculations and gives a detailed description of the program itself. The aim of the document is to give an indication of the grounds for having confidence in NAMMU as a performance assessment tool. In order to achieve this the following topics are discussed. The basic premises of the assessment approach and the purpose of and nature of the calculations that can be undertaken using NAMMU are outlined. The concepts of the validation of models and the considerations that can lead to increased confidence in models are described. The physical processes that can be modelled using NAMMU and the mathematical models and numerical techniques that are used to represent them are discussed in some detail. Finally, the grounds that would lead one to have confidence that NAMMU is fit for purpose are summarised.

  3. 非线性强度任意二聚的非线性链的透射性质%Transport properties of nonlinear chains with random dimer nonlinearity parameters

    Institute of Scientific and Technical Information of China (English)

    胡冬生; 张艳玲; 尹小刚; 徐江

    2012-01-01

    By using the recursion relation of discrete Schrodinger equation we investigate the transport properties of nonlinear chains with random dimer nonlinearity parameters. It is shown that there is a resonance state, which is just the product of the nonlinearity and the square of the incident wave amplitude modulus. The transmission coefficients are calculated in two conditions. One is that the transmission wave amplitude is a certain value, the other is that the incident wave amplitude modulus is a certain value. There are obvious differences in non-resonant states between the two kinds of conditions. The transmission is a single value function of the electronic energy for the former. However, it will be multi-stability for the latter. It is pointed out that the influence of the nonlinearity parameters on the transport properties can be exactly reflected only when the modulus of incident wave is set to be a certain value.%用离散的非线性薛定谔的递推关系研究了非线性强度任意二聚的非线性链的透射性质.结果表明该链存在一个共振透射态,共振态的能量为非线性强度与入射波振幅模平方的乘积;取出射波振幅为定值和取入射波振幅模为定值来计算透射系数,其结果在非共振态有明显的差别:取出射波振幅为定值时电子的透射随能量为单值函数,而取入射波振幅模为定值时电子的透射呈现多稳态.并指出只有取入射波振幅模为定值时才能真正反映非线性强度对电子透射性质的影响.

  4. Articulatory Parameters.

    Science.gov (United States)

    Ladefoged, Peter

    1980-01-01

    Summarizes the 16 parameters hypothesized to be necessary and sufficient for linguistic phonetic specifications. Suggests seven parameters affecting tongue shapes, three determining the positions of the lips, one controlling the position of the velum, four varying laryngeal actions, and one controlling respiratory activity. (RL)

  5. Parameter Estimation

    DEFF Research Database (Denmark)

    Sales-Cruz, Mauricio; Heitzig, Martina; Cameron, Ian;

    2011-01-01

    of optimisation techniques coupled with dynamic solution of the underlying model. Linear and nonlinear approaches to parameter estimation are investigated. There is also the application of maximum likelihood principles in the estimation of parameters, as well as the use of orthogonal collocation to generate a set...

  6. Inventory parameters

    CERN Document Server

    Sharma, Sanjay

    2017-01-01

    This book provides a detailed overview of various parameters/factors involved in inventory analysis. It especially focuses on the assessment and modeling of basic inventory parameters, namely demand, procurement cost, cycle time, ordering cost, inventory carrying cost, inventory stock, stock out level, and stock out cost. In the context of economic lot size, it provides equations related to the optimum values. It also discusses why the optimum lot size and optimum total relevant cost are considered to be key decision variables, and uses numerous examples to explain each of these inventory parameters separately. Lastly, it provides detailed information on parameter estimation for different sectors/products. Written in a simple and lucid style, it offers a valuable resource for a broad readership, especially Master of Business Administration (MBA) students.

  7. Numerical calculation and measuring of transport phenomena as integral parameters in cross-flowed finned tube heat exchangers; Numerische Berechnung und Messung der Transportvorgaenge sowie integraler Kenngroessen in quer angestroemten Rippenrohrwaermeuebertragern

    Energy Technology Data Exchange (ETDEWEB)

    Geiser, P.

    2003-07-01

    For the first row of extended finned tubes in cross flow, both the heat and mass transport and the integral pressure loss are determined. The tube shape, the dimensions of fin and tube, the positioning of tube and fin, the fin spacing, the thermal conductivity and the flow velocity are varied. For numerical simulation of the three-dimensional local transport phenomena, the balance equations for mass, momentum and energy are solved with the help of the commercial software FIDAP, taking account of the temperature-dependence of the material properties. From the resulting velocity, pressure and temperature fields in the configurations of the finned tube, derived characteristic parameters such as friction factor, integral fluid and fin temperature, fin efficiency, heat transfer coefficient, heat flux and fin-performance factor are determined with the help of self-developed evaluation programs. The numerical calculations of heat transfer and pressure loss show that a good correspondence with measured values in normal industrial applications for Re{<=}2000 is achieved. Local mass and heat transport in the fin duct is made visible via methods of convective mass transfer and is quantified for individual cases. For measurement purposes, enlarged models of the finned tubes are made of easily workable materials and set up in modular fashion so that tube shapes of very varied kinds can be investigated. Tube contours used in industrial applications are compared with a large number of new developments from the point of view of fluid dynamics and thermal properties. Local transport processes in the fin duct such as horseshoe vortices or separation areas which are of decisive significance for thermal performance can be made visible by means of the convective mass transfer method employed. The investigations have shown that finned tubes with large-radius of leading tube-profiles and large distances between the leading edge of the fin and the tube itself, as well as large fin

  8. RETROCK Project. Treatment of geosphere retention phenomena in safety assessments. Scientific basis of retention processes and their implementation in safety assessment models (WP2). Work Package 2 report of the RETROCK Concerted Action

    Energy Technology Data Exchange (ETDEWEB)

    Nykyri, M. [Safram Oy, Espoo (Finland)] [and others

    2004-10-01

    This report considers the present-day understanding and approaches to take into account retention and transport processes in the performance assessment (PA) models used in the evaluation of the long-term safety of deep geological repositories for radioactive waste. It is a product of Work Package 2 in the RETROCK Concerted Action, a part of EURATOM's research and training programme. The processes emphasised in RETROCK are the influences of the flow field, matrix diffusion, and sorption on radionuclide transport characteristics. These processes, and radioactive decay, provide the key terms to the transport equations of the PA models. The following processes are handled more cursorily: colloid-facilitated transport, microbial activity, gas-mediated transport, precipitation/coprecipitation, and off diagonal Onsager processes. The environment in question is saturated sparsely fractured rock in the repository far field. The fracture network offers flow paths for the groundwater transporting radionuclides away from a repository. The radionuclides in various chemical forms interact physically and chemically with other matter in groundwater, fracture surfaces, fracture infills and the rock matrix adjacent to the fractures. These interactions typically result in significant retardation, and decay, of radionuclides compared to the velocity of the groundwater. The PA models usually take into account retention phenomena using simplified concepts that are justified by their conservatism. They are complemented by a large variety of more detailed and realistic process-specific models that can be used to support the choice of data for PA models, as well as specific arguments made in safety cases. While the fundamental understanding, the conceptualisations of the phenomena, the models and the computing resources develop, the extensive data requirements often become a most restrictive factor to the use of a model. The difficulties in obtaining data tend to hinder the

  9. UZ Colloid Transport Model

    Energy Technology Data Exchange (ETDEWEB)

    M. McGraw

    2000-04-13

    The UZ Colloid Transport model development plan states that the objective of this Analysis/Model Report (AMR) is to document the development of a model for simulating unsaturated colloid transport. This objective includes the following: (1) use of a process level model to evaluate the potential mechanisms for colloid transport at Yucca Mountain; (2) Provide ranges of parameters for significant colloid transport processes to Performance Assessment (PA) for the unsaturated zone (UZ); (3) Provide a basis for development of an abstracted model for use in PA calculations.

  10. Radiation Transport

    Energy Technology Data Exchange (ETDEWEB)

    Urbatsch, Todd James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-06-15

    We present an overview of radiation transport, covering terminology, blackbody raditation, opacities, Boltzmann transport theory, approximations to the transport equation. Next we introduce several transport methods. We present a section on Caseology, observing transport boundary layers. We briefly broach topics of software development, including verification and validation, and we close with a section on high energy-density experiments that highlight and support radiation transport.

  11. Supergranular Parameters

    Science.gov (United States)

    Udayashankar, Paniveni

    2016-07-01

    I study the complexity of supergranular cells using intensity patterns from Kodaikanal solar observatory. The chaotic and turbulent aspect of the solar supergranulation can be studied by examining the interrelationships amongst the parameters characterizing supergranular cells namely size, horizontal flow field, lifetime and physical dimensions of the cells and the fractal dimension deduced from the size data. The findings are supportive of Kolmogorov's theory of turbulence. The Data consists of visually identified supergranular cells, from which a fractal dimension 'D' for supergranulation is obtained according to the relation P α AD/2 where 'A' is the area and 'P' is the perimeter of the supergranular cells. I find a fractal dimension close to about 1.3 which is consistent with that for isobars and suggests a possible turbulent origin. The cell circularity shows a dependence on the perimeter with a peak around (1.1-1.2) x 105 m. The findings are supportive of Kolmogorov's theory of turbulence.

  12. Evaluating the behavior, growth performance, immune parameters, and intestinal morphology of weaned piglets after simulated transport and heat stress when antibiotics are eliminated from the diet or replaced with L-glutamine

    Science.gov (United States)

    Study objectives were to evaluate the effects of post-weaning transport during heat stress (HS) and thermoneutral (TN) conditions when dietary antibiotics are removed or replaced with a nutraceutical. Sixty mixed sex piglets from 10 sows (n = 6 piglets/sow) were weaned (18.8 ± 0.8 d of age) and then...

  13. Neurotransmitter transporters

    DEFF Research Database (Denmark)

    Gether, Ulrik; Andersen, Peter H; Larsson, Orla M

    2006-01-01

    The concentration of neurotransmitters in the extracellular space is tightly controlled by distinct classes of membrane transport proteins. This review focuses on the molecular function of two major classes of neurotransmitter transporter that are present in the cell membrane of neurons and....../or glial cells: the solute carrier (SLC)1 transporter family, which includes the transporters that mediate the Na(+)-dependent uptake of glutamate, and the SLC6 transporter family, which includes the transporters that mediate the Na(+)-dependent uptake of dopamine, 5-HT, norepinephrine, glycine and GABA....... Recent research has provided substantial insight into the structure and function of these transporters. In particular, the recent crystallizations of bacterial homologs are of the utmost importance, enabling the first reliable structural models of the mammalian neurotransmitter transporters...

  14. Energy alternatives in urban transportation; Alternativas energeticas em transportes urbanos

    Energy Technology Data Exchange (ETDEWEB)

    Mello, Jose C. [SVO, Brasilia, DF (Brazil)

    1984-12-31

    The essay remarks the high dependence of petroleum derivative fuels, by analysing the energetic characteristics of urban transportation in Brazil. However, taking the global costs of energy in the country, only a little parcel of the petroleum expense is concerned to urban collective transportation. As a result, some energetic alternatives are being studied, in order to substitute petroleum derivative fuels, and parameters are being suggested to a national policy of urban transportation. (author). 8 refs., 5 tabs

  15. School Transportation.

    Science.gov (United States)

    Executive Educator, 1990

    1990-01-01

    This special section on student transportation offers a case study of a school system that recycles buses for safety drills; articles on fuel-saving strategies, the pros and cons of contracting for transportation services or operating a publicly owned bus fleet, and advice on full cost accounting for transportation costs; and a transportation…

  16. Prioritized Contact Transport Stream

    Science.gov (United States)

    Hunt, Walter Lee, Jr. (Inventor)

    2015-01-01

    A detection process, contact recognition process, classification process, and identification process are applied to raw sensor data to produce an identified contact record set containing one or more identified contact records. A prioritization process is applied to the identified contact record set to assign a contact priority to each contact record in the identified contact record set. Data are removed from the contact records in the identified contact record set based on the contact priorities assigned to those contact records. A first contact stream is produced from the resulting contact records. The first contact stream is streamed in a contact transport stream. The contact transport stream may include and stream additional contact streams. The contact transport stream may be varied dynamically over time based on parameters such as available bandwidth, contact priority, presence/absence of contacts, system state, and configuration parameters.

  17. Effect of Subsoil Compaction on Hydraulic Parameters

    DEFF Research Database (Denmark)

    Iversen, Bo Vangsø; Berisso, Feto Esimo; Schjønning, Per

    a significant trend of reduced macroporosity for the compacted upper depth. We conclude that the measured changes in the analyzed transport parameters support our hypothesis that the colloid-facilitated transport of agrochemicals in spatially connected macropores leads to a higher risk of contamination of water...

  18. 抗应激制剂对运输团头鲂血清生化和肝脏抗氧化指标的影响%Effects of Anti-stress Agents on Serum Biochemical Parameters and Hepatic Antioxidant Parameters in Wuchang Bream (Megalobrama amblycephala) during Long-distance Transportation

    Institute of Scientific and Technical Information of China (English)

    周传朋; 刘波; 谢骏; 戈贤平; 徐跑; 王可宝; 周群兰; 潘良坤; 陈汝丽

    2014-01-01

    The serum cortisol (COR) ,levels of 3 ,5 ,3′ - triiodothyronine (T3) ,complement 3 (C3) , complement 4 (C4) ,hepatic malondialdehyde (MDA) ,activity of superoxide dismutase (SOD) ,and total antioxidant capacity (T-AOC) were determined in Wuchang bream (Megalobrama amblycephala) with initial body weight of (600 ± 12) g held in 1m3 tanks of 750 fish fed the diets containing 20 mg/L vitamin C , glutamine or anti-stress compund (anti-stress agents ) (without addition as control group ) during long-distance transportation period of 0 h ,4 h ,8 h ,and 12 h to evaluate the effect of anti-stress agents on the serum biochemical parameters and hepatic antioxidant abilities during the long-distance transportation period .The results showed that the anti-stress agents led to significantly (Pglutamine>anti-stress compound .%研究了在运输中添加维生素C,谷氨酰胺和抗应激复合物对团头鲂血清生化指标和肝脏抗氧化指标的影响,探讨团头鲂运输后高死亡率的原因以及维生素C、谷氨酰胺和抗应激复合物对运输应激的缓解作用。在运输团头鲂0、4、8、12 h后,分别采集团头鲂血液和肝脏样品,测定了血清皮质醇、三碘甲腺原氨酸、补体3、补体4、肝脏丙二醛含量、超氧化物歧化酶活力、总抗氧化能力等指标。试验结果表明,经过4 h后,与对照组相比,维生素C组血清皮质醇和肝脏丙二醛的含量显著降低(P<0.05);抗应激复合物组血清补体3和补体4含量显著升高(P<0.05);维生素C组、谷氨酰胺和抗应激复合物组肝脏超氧化物歧化酶活性显著提高(P<0.05);维生素C组和谷氨酰胺组肝脏总抗氧化能力分别显著升高(P<0.05)。经过8 h ,与对照组相比,维生素C组、谷氨酰胺组和抗应激复合物组血清皮质醇含量显著降低(P<0.05);维生素C组和抗应激复合物组血清补体3含量分别显著升高(P<0.05)

  19. Sustainable Transportation

    DEFF Research Database (Denmark)

    Hall, Ralph P.; Gudmundsson, Henrik; Marsden, Greg

    2014-01-01

    The transportation system is the backbone of economic and social progress and the means by which humans access goods and services and connect with one another. Yet, as the scale of transportation activities has grown worldwide, so too have the negative environmental, social, and economic impacts...... that relate to the construction and maintenance of transportation infrastructure and the operation or use of the different transportation modes. The concept of sustainable transportation emerged in response to these concerns as part of the broader notion of sustainable development. Given the transportation...... sector’s significant contribution to global challenges such as climate change, it is often said that sustainable development cannot be achieved without sustainable transportation....

  20. Estresse devido ao transporte e à ação da benzocaína em parâmetros hematológicos e população de parasitas em matrinxã, Brycon cephalus (Günther, 1869 (Osteichthyes, Characidae Transport with different benzocaine concentrations and its consequences on hematological parameters and gill parasite population of matrinxã Brycon cephalus (Günther, 1869 (Osteichthyes, Characidae

    Directory of Open Access Journals (Sweden)

    Maurício Laterça Martins

    2002-05-01

    efeitos negativos das duas concentrações mais altas em vários parâmetros hematológicos e no número de Piscinoodinium sp. aderido às brânquias. Concluiu-se, portanto que o uso da benzocaína não reduziu o estresse causado pelo transporte em matrinxãs, atuando inclusive como agente estressor adicional.The objective of this study was to evaluate the transport stressing effects and the different benzocaine concentrations on hematological parameters and parasite population of matrinxã Brycon cephalus (Osteichthyes, Characidae. Thirty fish (1.0 kg mean weight were hauled in four 200-L plastic tanks for four hours, at different benzocaine concentrations (B0 = 0.0 g/L, B1 = 5.0 g/L, B2 = 10.0 g/L and B3 = 20 g/L. Before loading, blood and gills of 5 fish were collected. Other three samplings were performed after transport, and 24 and 96 hours later (recovery period. Blood cortisol, glucose, hematocrit, white cell differential count and the number of the gill parasite Piscinoodinium sp. were determined. Plasma cortisol increased in all treatments after transport, returning to initial levels 24 hours later. Blood glucose was also elevated after transport in all treatments, but only B0 and B1 fish recovered initial levels in 24 hours. B2 and B3 fish did not recover the initial levels until the end of the experimental period. After transport, the lymphocytes relative percentage decreased and the neuthrophils relative percentage increased, in all treatments. Ninety-six hours later, only B0 and B1 fish had recovered the initial levels of these parameters. The number of Piscinoodinium sp. on the gills of B3 fish was higher than in the other treatments 96 hours after transportation. The use of benzocaine did not mitigate stress responses and some negative effects were observed in fish transported with the highest concentrations.

  1. Sustainable Transportation

    DEFF Research Database (Denmark)

    Hall, Ralph P.; Gudmundsson, Henrik; Marsden, Greg

    2014-01-01

    The transportation system is the backbone of economic and social progress and the means by which humans access goods and services and connect with one another. Yet, as the scale of transportation activities has grown worldwide, so too have the negative environmental, social, and economic impacts ...... sector’s significant contribution to global challenges such as climate change, it is often said that sustainable development cannot be achieved without sustainable transportation....

  2. From geosphere to biosphere: circulation of matter in nature

    Directory of Open Access Journals (Sweden)

    Rodrigues, Ana Paula L.

    2011-11-01

    Full Text Available Con este experimento, para alumnos de la educación secundaria, se pretende estimular el gusto por la ciencia experimental. De una manera lúdica, vamos a intentar ejemplificar el movimiento de la materia en la naturaleza e ilustrar las consecuencias que los desequilibrios en los ciclos biogeoquímicos pueden tener para los seres vivos.

  3. SEDIMENT TRANSPORT EXPERIMENTSIN UNSTEADY FLOWS

    Institute of Scientific and Technical Information of China (English)

    DE SUTTER R.; HUYGENS M.; VERHOEVEN R.

    2001-01-01

    By means of a test flume with semi-circular cross-section, bedload and suspended-sediment transport of non-cohesive material have been studied in transient flow. The experimental facility enables us to investigate the time evolution of friction and transport parameters. Preliminary measurements with a fixed bottom instead of a sediment bed yield a reliable assessment of flow and friction characteristics. Time sequence in unsteady flow of the relevant parameters is revealed. The influence of turbulence variation and shear stress variation on the transport is investigated. As existing transport equations are found to be in poor agreement with experimental data, a new "engineering" concept is constructed which relates friction velocity to transport.

  4. Transport Phenomena.

    Science.gov (United States)

    McCready, Mark J.; Leighton, David T.

    1987-01-01

    Discusses the problems created in graduate chemical engineering programs when students enter with a wide diversity of understandings of transport phenomena. Describes a two-semester graduate transport course sequence at the University of Notre Dame which focuses on fluid mechanics and heat and mass transfer. (TW)

  5. Modelling of radon transport in porous media

    NARCIS (Netherlands)

    van der Graaf, E.R.; de Meijer, R.J.; Katase, A; Shimo, M

    1998-01-01

    This paper aims to describe the state of the art of modelling radon transport in soil on basis of multiphase radon transport equations. Emphasis is given to methods to obtain a consistent set of input parameters needed For such models. Model-measurement comparisons with the KVI radon transport Facil

  6. Modelling of radon transport in porous media

    NARCIS (Netherlands)

    van der Graaf, E.R.; de Meijer, R.J.; Katase, A; Shimo, M

    1998-01-01

    This paper aims to describe the state of the art of modelling radon transport in soil on basis of multiphase radon transport equations. Emphasis is given to methods to obtain a consistent set of input parameters needed For such models. Model-measurement comparisons with the KVI radon transport Facil

  7. Animal Transports

    Directory of Open Access Journals (Sweden)

    Diana Ludrovcová

    2016-08-01

    Full Text Available Purpose and Originality: The research is aimed to the animal transports issue, from two points of view – first is the animal cruelty and second is the policy and economic consideration. The goal is to acquaint the readers with the transports risks and its cruelty and evaluation of the economic, political aspects for he involved countries. The study is oriented on more points of view, what is rare in works with a similar theme. Method: This paper examines many issues and examinations from different authors and subsequently summarized the findings with authors own knowledge to one expanded unit. Results: Results proves, that livestock transports have negative impact on animal´s health, environment. Number of transported animals is rising every year. Society: Research familiarize the society with the animal transports, cruelty against animals during them, and influence of transports on some countries, their economy, policy. People get better informed and can form their own opinion on this topic. They may start acting, undertaking some steps to improve the present situation, what could help a lot to animals and environment. Limitations / further research: Future research could show progress and improvement of transports, quality of food supply and economics.

  8. SUSTAINABLE TRANSPORTATION

    Directory of Open Access Journals (Sweden)

    Linda STEG

    2007-01-01

    Full Text Available This paper discusses possible contributions of psychologists to sustainable transportation. It is argued that in order to reach sustainable transportation, among others, behaviour changes of individual car users are needed. As transport policies will be more effective if they target important antecedents of travel behaviour, first, factors influencing such behaviour are discussed. It is argued that car use is very attractive and sometimes even necessary for many different reasons. This implies that a combination of policies is called for, each targeting different factors that support car use and hinder the use of more sustainable modes of transport. Next, the paper elaborates on policy strategies that may be employed to achieve sustainable transportation by changing car use. Increasing the attractiveness of sustainable transport modes by means of pull measures seems not sufficient to reduce the level of car use. Besides, car use should be made less attractive by means of push measures to force drivers to reconsider their travel behaviour. The acceptability of such policies may be increased by clearly communicating the aim of these policies, and the expected positive consequences (e.g., less congestion, improved environmental quality. Moreover, possible negative effects for individual freedom may be compensated by implementing additional policies aimed at facilitating the use of sustainable transport modes.

  9. Sediment Transport

    DEFF Research Database (Denmark)

    Liu, Zhou

    Flow and sediment transport are important in relation to several engineering topics, e.g. erosion around structures, backfilling of dredged channels and nearshore morphological change. The purpose of the present book is to describe both the basic hydrodynamics and the basic sediment transport...... mechanics. Chapter 1 deals with fundamentals in fluid mechanics with emphasis on bed shear stress by currents, while chapter 3 discusses wave boundary layer theory. They are both written with a view to sediment transport. Sediment transport in rivers, cross-shore and longshore are dealt with in chapters 2......, 4 and 5, respectively. It is not the intention of the book to give a broad review of the literature on this very wide topic. The book tries to pick up information which is of engineering importance. An obstacle to the study of sedimentation is the scale effect in model tests. Whenever small...

  10. Transport Phenomena.

    Science.gov (United States)

    Shah, D. B.

    1984-01-01

    Describes a course designed to achieve a balance between exposing students to (1) advanced topics in transport phenomena, pointing out similarities and differences between three transfer processes and (2) common methods of solving differential equations. (JN)

  11. Nicaragua - Transportation

    Data.gov (United States)

    Millennium Challenge Corporation — The evaluation examines impacts of the Transportation Project in three ways. First, we calculate economic rates of return associated with reduced user costs for each...

  12. Evaluation of colloid transport issues and recommendations for SKI performance assessments

    Energy Technology Data Exchange (ETDEWEB)

    Wickham, S. M.; Bennett, D. G.; Higgo, J. J. W. [Galson Sciences Ltd., Oakham (United Kingdom)

    2000-08-01

    The primary objective of this project was to develop recommendations to SKI for evaluating the potential significance of colloids in performance assessment (PA) studies by: Updating a previous review of the treatment of colloids in PA studies for radioactive waste repositories and to include information on PAs published in the period 1997-1999. We have reviewed sixteen PAs conducted in nine countries and have made the following observations: All PAs include colloid formation and colloid transport in their FEP list. Although some programmes have deferred consideration of colloidal radionuclide transport until further research has been performed, more recent PAs do account for the effects of colloids. PAs of disposal systems in which the waste canister is surrounded by a bentonite buffer do not consider the effect of colloids on the source term. These PAs assume that all colloids are filtered by the bentonite buffer and cannot escape from the near-field. PAs of disposal systems with no bentonite buffer have to account for mobilisation of radionuclides from the waste by colloids. The concentration of colloids that may form in the repository is a key uncertainty. Many PA programmes have modelled colloidal radionuclide transport in the geosphere using one-dimensional transport equations. No PA has included a comprehensive treatment of colloid transport using mechanistic modelling. Some PAs have not undertaken modelling of colloid transport in the geosphere, but have relied instead on arguments that such transport processes will be of low consequence to the performance of the disposal system. Five PAs have shown the effects of colloid transport through the geosphere to be potentially significant. For the disposal of spent nuclear fuel, SKB has developed the KBS-3 concept. For the disposal of long-lived low-level and intermediate-level radioactive waste, SKB has developed the SFL 3-5 concept. In the SFL 3-5 concept, waste is placed in underground disposal caverns and

  13. Transport service

    CERN Document Server

    C. Cerruti / FI

    2006-01-01

    A large number of pallet-crates (panières grillagées), which are used for transporting equipment and for removals, have been dispatched to various locations around the CERN site. We kindly request all users who may have such crates in their possession and no longer need them to make the necessary arrangements (EDH request to the Transport Group) to return them to Building 133, as we currently have no more in stock. Claude CERRUTI / FI-PI

  14. Third-order TRANSPORT: A computer program for designing charged particle beam transport systems

    Energy Technology Data Exchange (ETDEWEB)

    Carey, D.C. [Fermi National Accelerator Lab., Batavia, IL (United States); Brown, K.L.; Rothacker, F. [Stanford Linear Accelerator Center, Menlo Park, CA (United States)

    1995-05-01

    TRANSPORT has been in existence in various evolutionary versions since 1963. The present version of TRANSPORT is a first-, second-, and third-order matrix multiplication computer program intended for the design of static-magnetic beam transport systems. This report discusses the following topics on TRANSPORT: Mathematical formulation of TRANSPORT; input format for TRANSPORT; summaries of TRANSPORT elements; preliminary specifications; description of the beam; physical elements; other transformations; assembling beam lines; operations; variation of parameters for fitting; and available constraints -- the FIT command.

  15. Transport in gyrokinetic tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Mynick, H.E.; Parker, S.E.

    1995-01-01

    A comprehensive study of transport in full-volume gyrokinetic (gk) simulations of ion temperature gradient driven turbulence in core tokamak plasmas is presented. Though this ``gyrokinetic tokamak`` is much simpler than experimental tokamaks, such simplicity is an asset, because a dependable nonlinear transport theory for such systems should be more attainable. Toward this end, we pursue two related lines of inquiry. (1) We study the scalings of gk tokamaks with respect to important system parameters. In contrast to real machines, the scalings of larger gk systems (a/{rho}{sub s} {approx_gt} 64) with minor radius, with current, and with a/{rho}{sub s} are roughly consistent with the approximate theoretical expectations for electrostatic turbulent transport which exist as yet. Smaller systems manifest quite different scalings, which aids in interpreting differing mass-scaling results in other work. (2) With the goal of developing a first-principles theory of gk transport, we use the gk data to infer the underlying transport physics. The data indicate that, of the many modes k present in the simulation, only a modest number (N{sub k} {approximately} 10) of k dominate the transport, and for each, only a handful (N{sub p} {approximately} 5) of couplings to other modes p appear to be significant, implying that the essential transport physics may be described by a far simpler system than would have been expected on the basis of earlier nonlinear theory alone. Part of this analysis is the inference of the coupling coefficients M{sub kpq} governing the nonlinear mode interactions, whose measurement from tokamak simulation data is presented here for the first time.

  16. Useful Scaling Parameters for the Pulse Tube

    Science.gov (United States)

    Lee, J. M.; Kittel, P.; Timmerhaus, K. D.; Radebaugh, R.; Cheng, Pearl L. (Technical Monitor)

    1995-01-01

    A set of eight non-dimensional scaling parameters for use in evaluating the performance of Pulse Tube Refrigerators is presented. The parameters result after scaling the mass, momentum and energy conservation equations for an axisymmetric, two-dimensional system. The physical interpretation of the parameters are described, and their usefulness is outlined for the enthalpy flow tube (open tube of the pulse tube). The scaling parameters allow the experimentalist to characterize three types of transport: enthalpy flow, mass streaming and heat transfer between the gas and the tube. Also reported are the results from a flow visualization experiment in which steady mass streaming in compressible oscillating flow is observed.

  17. Comparison of two numerical modelling codes for hydraulic and transport calculations in the near-field

    Energy Technology Data Exchange (ETDEWEB)

    Kalin, J., E-mail: jan.kalin@zag.s [Slovenian National Building and Civil Engineering Institute, Dimiceva 12, SI-1000 Ljubljana (Slovenia); Petkovsek, B., E-mail: borut.petkovsek@zag.s [Slovenian National Building and Civil Engineering Institute, Dimiceva 12, SI-1000 Ljubljana (Slovenia); Montarnal, Ph., E-mail: philippe.montarnal@cea.f [CEA/Saclay, DM2S/SFME/LSET, Gif-sur-Yvette, 91191 cedex (France); Genty, A., E-mail: alain.genty@cea.f [CEA/Saclay, DM2S/SFME/LSET, Gif-sur-Yvette, 91191 cedex (France); Deville, E., E-mail: estelle.deville@cea.f [CEA/Saclay, DM2S/SFME/LSET, Gif-sur-Yvette, 91191 cedex (France); Krivic, J., E-mail: jure.krivic@geo-zs.s [Geological Survey of Slovenia, Dimiceva 14, SI-1000 Ljubljana (Slovenia); Ratej, J., E-mail: joze.ratej@geo-zs.s [Geological Survey of Slovenia, Dimiceva 14, SI-1000 Ljubljana (Slovenia)

    2011-04-15

    In the past years the Slovenian Performance Analysis/Safety Assessment team has performed many generic studies for the future Slovenian low and intermediate level waste repository, most recently a Special Safety Analysis for the Krsko site. The modelling approach was to split the problem into three parts: near-field (detailed model of the repository), far-field (i.e., geosphere) and biosphere. In the Special Safety Analysis the code used to perform the near-field calculations was Hydrus2D. Recently the team has begun a cooperation with the French Commisariat al'Energie Atomique/Saclay (CEA/Saclay) and, as a part of this cooperation, began investigations into using the Alliances numerical platform for near-field calculations in order to compare the overall approach and calculated results. The article presents the comparison between these two codes for a silo-type repository that was considered in the Special Safety Analysis. The physical layout and characteristics of the repository are presented and a hydraulic and transport model of the repository is developed and implemented in Alliances. Some analysis of sensitivity to mesh fineness and to simulation timestep has been preformed and is also presented. The compared quantity is the output flux of radionuclides on the boundary of the model. Finally the results from Hydrus2D and Alliances are compared and the differences and similarities are commented.

  18. Development of Regional Transport Logistics Terminal- Transport Logistics Approach

    Directory of Open Access Journals (Sweden)

    Peter Jenček

    2008-07-01

    Full Text Available Reaching decisions in the process of establishment and operationof a regional transport logistics terminal performingintermodal transport and related activities should be based onthe results of preliminary analysis. The selection of the appropriatelocation for the regional transport logistics terminal is ofcrucial importance as it affects directly and/or indirectly the initialfinancial investment, environmental and spatial issues aswell as terminal operating costs and commercial sustainability.In the decision-making process regarding the location ofintermodal terminals or with regard to building of a new regionalintermodal terminal at a specific location a thoroughtransport logistics analysis should be performed. The paperpresents the methodology developed for transport logisticsanalysis of regional intermodal transport logistics terminals,based on the sets of parameters, criteria and indicators whichenable the determination of the overall performance index for aparticular terminal location.

  19. Travel and transport

    DEFF Research Database (Denmark)

    Bill, Jan; Roesdahl, Else

    2007-01-01

    On the interrelationship between travel, transport and society; on land transport, sea and river transport, and on winter transport;  on the related technologies and their developments......On the interrelationship between travel, transport and society; on land transport, sea and river transport, and on winter transport;  on the related technologies and their developments...

  20. Optimal transport

    CERN Document Server

    Eckmann, B

    2008-01-01

    At the close of the 1980s, the independent contributions of Yann Brenier, Mike Cullen and John Mather launched a revolution in the venerable field of optimal transport founded by G Monge in the 18th century, which has made breathtaking forays into various other domains of mathematics ever since. The author presents a broad overview of this area.

  1. Transport modeling

    Institute of Scientific and Technical Information of China (English)

    R.E. Waltz

    2007-01-01

    @@ There has been remarkable progress during the past decade in understanding and modeling turbulent transport in tokamaks. With some exceptions the progress is derived from the huge increases in computational power and the ability to simulate tokamak turbulence with ever more fundamental and physically realistic dynamical equations, e.g.

  2. Transport fuel

    DEFF Research Database (Denmark)

    Ronsse, Frederik; Jørgensen, Henning; Schüßler, Ingmar

    2014-01-01

    Worldwide, the use of transport fuel derived from biomass increased four-fold between 2003 and 2012. Mainly based on food resources, these conventional biofuels did not achieve the expected emission savings and contributed to higher prices for food commod - ities, especially maize and oilseeds...

  3. Anomalous transport

    Science.gov (United States)

    Cheverry, Christophe

    2017-02-01

    This article is concerned with the relativistic Vlasov equation, for collisionless axisymmetric plasmas immersed in a strong magnetic field, like in tokamaks. It provides a consistent kinetic treatment of the microscopic particle phase-space dynamics. It shows that the turbulent transport can be completely described through WKB expansions.

  4. Transport system

    NARCIS (Netherlands)

    Drenth, K.F.

    1999-01-01

    The transport system comprises at least one road surface (2) and at least one vehicle (4) on wheels (6). The road surface (2) has a substantially bowl-shaped cross section and the vehicle (4) is designed so that the wheels (6) run directly on the road surface (2) while the road surface (2) acts as a

  5. Lumped-parameter models

    Energy Technology Data Exchange (ETDEWEB)

    Ibsen, Lars Bo; Liingaard, M.

    2006-12-15

    A lumped-parameter model represents the frequency dependent soil-structure interaction of a massless foundation placed on or embedded into an unbounded soil domain. In this technical report the steps of establishing a lumped-parameter model are presented. Following sections are included in this report: Static and dynamic formulation, Simple lumped-parameter models and Advanced lumped-parameter models. (au)

  6. Redefining solubility parameters: the partial solvation parameters.

    Science.gov (United States)

    Panayiotou, Costas

    2012-03-21

    The present work reconsiders a classical and universally accepted concept of physical chemistry, the solubility parameter. Based on the insight derived from modern quantum chemical calculations, a new definition of solubility parameter is proposed, which overcomes some of the inherent restrictions of the original definition and expands its range of applications. The original single solubility parameter is replaced by four partial solvation parameters reflecting the dispersion, the polar, the acidic and the basic character of the chemical compounds as expressed either in their pure state or in mixtures. Simple rules are adopted for the definition and calculation of these four parameters and their values are tabulated for a variety of common substances. In contrast, however, to the well known Hansen solubility parameters, their design and evaluation does not rely exclusively on the basic rule of "similarity matching" for solubility but it makes also use of the other basic rule of compatibility, namely, the rule of "complementarity matching". This complementarity matching becomes particularly operational with the sound definition of the acidic and basic components of the solvation parameter based on the third σ-moments of the screening charge distributions of the quantum mechanics-based COSMO-RS theory. The new definitions are made in a simple and straightforward manner, thus, preserving the strength and appeal of solubility parameter stemming from its simplicity. The new predictive method has been applied to a variety of solubility data for systems of pharmaceuticals and polymers. The results from quantum mechanics calculations are critically compared with the results from Abraham's acid/base descriptors.

  7. Quality standards and quality of transport services

    Directory of Open Access Journals (Sweden)

    Ljubislav T. Vasin

    2012-04-01

    Full Text Available The paper points out to the contribution of quality standard application in all areas of human life. The detailed explanations of terms quality, product and service are given as well. Considering the fact that a result of the transportation activity is a change of the product location - transportation, the paper gives special attention to the service. A focus is also on the term transportation service, as well as the parameters of quality of transportation for passenger and cargo transportation service. In the closing section, the application of quality standards in the Serbian Army will be briefly discussed.

  8. Glutamine transport in submitochondrial particles

    Energy Technology Data Exchange (ETDEWEB)

    Sastrasinh, S.; Sastrasinh, M.

    1989-12-01

    Glutamine transport was studied in submitochondrial particles (SMP) to avoid interference from glutamine metabolism. Phosphate-dependent glutaminase activity in SMP was only 0.04% of that in intact mitochondria. The uptake of glutamine in SMP represented both the transport into vesicles and membrane binding (about one-third of total uptake). Sulfhydryl reagents inhibited glutamine uptake in SMP. The uptake of L-({sup 3}H)glutamine increased more than twofold in SMP preloaded with 1 mM L-glutamine, an effect that was not seen with 1 mM D-glutamine. The uptake of L-({sup 3}H)glutamine was inhibited in the presence of either L-glutamine or L-alanine in the incubation medium. Other amino acids did not inhibit glutamine uptake. Alanine was also shown to trans-stimulate glutamine transport in SMP and cis-inhibit glutamine transport in both SMP and intact mitochondria. Glutamine transport showed a positive cooperativity effect with a Hill coefficient of 1.45. Metabolic acidosis increased the affinity of the transporter for glutamine without any change in other kinetic parameters. These data indicated that mitochondrial glutamine transport occurs via a specific carrier with multiple binding sites and that the transport of glutamine into mitochondria has an important role in increased ammoniagenesis during metabolic acidosis.

  9. Transport Properties for Combustion Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Brown, N.J.; Bastein, L.; Price, P.N.

    2010-02-19

    This review examines current approximations and approaches that underlie the evaluation of transport properties for combustion modeling applications. Discussed in the review are: the intermolecular potential and its descriptive molecular parameters; various approaches to evaluating collision integrals; supporting data required for the evaluation of transport properties; commonly used computer programs for predicting transport properties; the quality of experimental measurements and their importance for validating or rejecting approximations to property estimation; the interpretation of corresponding states; combination rules that yield pair molecular potential parameters for unlike species from like species parameters; and mixture approximations. The insensitivity of transport properties to intermolecular forces is noted, especially the non-uniqueness of the supporting potential parameters. Viscosity experiments of pure substances and binary mixtures measured post 1970 are used to evaluate a number of approximations; the intermediate temperature range 1 < T* < 10, where T* is kT/{var_epsilon}, is emphasized since this is where rich data sets are available. When suitable potential parameters are used, errors in transport property predictions for pure substances and binary mixtures are less than 5 %, when they are calculated using the approaches of Kee et al.; Mason, Kestin, and Uribe; Paul and Warnatz; or Ern and Giovangigli. Recommendations stemming from the review include (1) revisiting the supporting data required by the various computational approaches, and updating the data sets with accurate potential parameters, dipole moments, and polarizabilities; (2) characterizing the range of parameter space over which the fit to experimental data is good, rather than the current practice of reporting only the parameter set that best fits the data; (3) looking for improved combining rules, since existing rules were found to under-predict the viscosity in most cases; (4

  10. A simulation of water pollution model parameter estimation

    Science.gov (United States)

    Kibler, J. F.

    1976-01-01

    A parameter estimation procedure for a water pollution transport model is elaborated. A two-dimensional instantaneous-release shear-diffusion model serves as representative of a simple transport process. Pollution concentration levels are arrived at via modeling of a remote-sensing system. The remote-sensed data are simulated by adding Gaussian noise to the concentration level values generated via the transport model. Model parameters are estimated from the simulated data using a least-squares batch processor. Resolution, sensor array size, and number and location of sensor readings can be found from the accuracies of the parameter estimates.

  11. Copper transport.

    Science.gov (United States)

    Linder, M C; Wooten, L; Cerveza, P; Cotton, S; Shulze, R; Lomeli, N

    1998-05-01

    In adult humans, the net absorption of dietary copper is approximately 1 mg/d. Dietary copper joins some 4-5 mg of endogenous copper flowing into the gastrointestinal tract through various digestive juices. Most of this copper returns to the circulation and to the tissues (including liver) that formed them. Much lower amounts of copper flow into and out of other major parts of the body (including heart, skeletal muscle, and brain). Newly absorbed copper is transported to body tissues in two phases, borne primarily by plasma protein carriers (albumin, transcuprein, and ceruloplasmin). In the first phase, copper goes from the intestine to the liver and kidney; in the second phase, copper usually goes from the liver (and perhaps also the kidney) to other organs. Ceruloplasmin plays a role in this second phase. Alternatively, liver copper can also exit via the bile, and in a form that is less easily reabsorbed. Copper is also present in and transported by other body fluids, including those bathing the brain and central nervous system and surrounding the fetus in the amniotic sac. Ceruloplasmin is present in these fluids and may also be involved in copper transport there. The concentrations of copper and ceruloplasmin in milk vary with lactational stage. Parallel changes occur in ceruloplasmin messenger RNA expression in the mammary gland (as determined in pigs). Copper in milk ceruloplasmin appears to be particularly available for absorption, at least in rats.

  12. Models and parameters for environmental radiological assessments

    Energy Technology Data Exchange (ETDEWEB)

    Miller, C W [ed.

    1984-01-01

    This book presents a unified compilation of models and parameters appropriate for assessing the impact of radioactive discharges to the environment. Models examined include those developed for the prediction of atmospheric and hydrologic transport and deposition, for terrestrial and aquatic food-chain bioaccumulation, and for internal and external dosimetry. Chapters have been entered separately into the data base. (ACR)

  13. Evaluation of parameter uncertainties obtained from in-situ tracer experiments

    Energy Technology Data Exchange (ETDEWEB)

    Sawada, Atsushi; Yoshino, Naoto [Japan Nuclear Cycle Development Inst., Tokai Works, Tokai, Ibaraki (Japan); Ijiri, Yuji; Hata, Akihito [Taisei Corp., Tokyo (Japan); Hosono, Kenichi [Geoscience Research Laboratory, Yamato, Kanagawa (Japan)

    2003-03-01

    Radionuclide transport parameter uncertainty is an important consideration in the safety assessment of high-level radioactive waste disposal. This paper describes the development of a method for the quantitative estimation of transport parameter uncertainties from in-situ tracer experiments. The method utilizes a probabilistic inversion based on the maximum likelihood method. Transport parameters and their uncertainties are derived from a series of conservative and reactive tracer tests conducted in a single fracture at the Aespoe Hard Rock Laboratory in Sweden. These transport parameters and uncertainties are useful for evaluating the influence of parameter uncertainty on safety assessment. (author)

  14. Transportation optimization with fuzzy trapezoidal numbers based on possibility theory.

    Science.gov (United States)

    He, Dayi; Li, Ran; Huang, Qi; Lei, Ping

    2014-01-01

    In this paper, a parametric method is introduced to solve fuzzy transportation problem. Considering that parameters of transportation problem have uncertainties, this paper develops a generalized fuzzy transportation problem with fuzzy supply, demand and cost. For simplicity, these parameters are assumed to be fuzzy trapezoidal numbers. Based on possibility theory and consistent with decision-makers' subjectiveness and practical requirements, the fuzzy transportation problem is transformed to a crisp linear transportation problem by defuzzifying fuzzy constraints and objectives with application of fractile and modality approach. Finally, a numerical example is provided to exemplify the application of fuzzy transportation programming and to verify the validity of the proposed methods.

  15. Transporter Classification Database (TCDB)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Transporter Classification Database details a comprehensive classification system for membrane transport proteins known as the Transporter Classification (TC)...

  16. Diffusive gas transport through flooded rice systems

    NARCIS (Netherlands)

    Bodegom, van P.M.; Groot, T.; Hout, van de B.; Leffelaar, P.A.; Goudriaan, J.

    2001-01-01

    A fully mechanistic model based on diffusion equations for gas transport in a flooded rice system is presented. The model has transport descriptions for various compartments in the water-saturated soil and within the plant. Plant parameters were estimated from published data and experiments independ

  17. Peritoneal Fluid Transport rather than Peritoneal Solute Transport Associates with Dialysis Vintage and Age of Peritoneal Dialysis Patients.

    Science.gov (United States)

    Waniewski, Jacek; Antosiewicz, Stefan; Baczynski, Daniel; Poleszczuk, Jan; Pietribiasi, Mauro; Lindholm, Bengt; Wankowicz, Zofia

    2016-01-01

    During peritoneal dialysis (PD), the peritoneal membrane undergoes ageing processes that affect its function. Here we analyzed associations of patient age and dialysis vintage with parameters of peritoneal transport of fluid and solutes, directly measured and estimated based on the pore model, for individual patients. Thirty-three patients (15 females; age 60 (21-87) years; median time on PD 19 (3-100) months) underwent sequential peritoneal equilibration test. Dialysis vintage and patient age did not correlate. Estimation of parameters of the two-pore model of peritoneal transport was performed. The estimated fluid transport parameters, including hydraulic permeability (LpS), fraction of ultrasmall pores (α u), osmotic conductance for glucose (OCG), and peritoneal absorption, were generally independent of solute transport parameters (diffusive mass transport parameters). Fluid transport parameters correlated whereas transport parameters for small solutes and proteins did not correlate with dialysis vintage and patient age. Although LpS and OCG were lower for older patients and those with long dialysis vintage, αu was higher. Thus, fluid transport parameters--rather than solute transport parameters--are linked to dialysis vintage and patient age and should therefore be included when monitoring processes linked to ageing of the peritoneal membrane.

  18. Setting parameters in the cold chain

    Directory of Open Access Journals (Sweden)

    Victoria Rodríguez

    2011-12-01

    Full Text Available Breaks in the cold chain are important economic losses in food and pharmaceutical companies. Many of the failures in the cold chain are due to improper adjustment of equipment parameters such as setting the parameters for theoretical conditions, without a corresponding check in normal operation. The companies that transport refrigeratedproducts must be able to adjust the parameters of the equipment in an easy and quick to adapt their functioning to changing environmental conditions. This article presents the results of a study carried out with a food distribution company. The main objective of the study is to verify the effectiveness of Six Sigma as a methodological toolto adjust the equipment in the cold chain. The second objective is more speciÞ c and is to study the impact of: reducing the volume of storage in the truck, the initial temperature of the storage areain the truck and the frequency of defrost in the transport of refrigerated products.

  19. Charge transport in organic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Ortmann, Frank

    2009-07-01

    The understanding of charge transport is one of the central goals in the research on semiconducting crystals. For organic crystals this is particularly complicated due to the strength of the electron-phonon interaction which requires the description of a seamless transition between the limiting cases of a coherent band-transport mechanism and incoherent hopping. In this thesis, charge transport phenomena in organic crystals are studied by theoretical means. A theory for charge transport in organic crystals is developed which covers the whole temperature range from low T, where it reproduces an expression from the Boltzmann equation for band transport, via elevated T, where it generalizes Holstein's small-polaron theory to finite bandwidths, up to high T, for which a temperature dependence equal to Marcus' electron-transfer theory is obtained. Thereby, coherent band transport and thermally induced hopping are treated on equal footing while simultaneously treating the electron-phonon interaction non-perturbatively. By avoiding the approximation of narrow polaron bands the theory allows for the description of large and small polarons and serves as a starting point for computational studies. The theoretical description is completed by using ab initio material parameters for the selected crystals under study. These material parameters are taken from density functional theory calculations for durene, naphthalene, and guanine crystals. Besides the analysis of the transport mechanism, special focus is put on the study of the relationship between mobility anisotropy and structure of the crystals. This study is supported by a 3D-visualization method for the transport channels in such crystals which has been derived in this thesis. (orig.)

  20. Mobile Transporter

    Science.gov (United States)

    2001-01-01

    The Space Shuttle Atlantis, STS-110 mission, deployed this railcar, called the Mobile Transporter, and an initial 43-foot section of track, the S0 (S-zero) truss, preparing the International Space Station (ISS) for future spacewalks. The first railroad in space, the Mobile Transporter will allow the Station's robotic arm to travel up and down the finished truss for future assembly and maintenance. The 27,000-pound S0 truss is the first of 9 segments that will make up the Station's external framework that will eventually stretch 356 feet (109 meters), or approximately the length of a football field. The completed truss structure will hold solar arrays and radiators to provide power and cooling for additional international research laboratories from Japan and Europe that will be attached to the Station. The Space Shuttle Orbiter Atlantis, STS-110 mission, was launched April 8, 2002 and returned to Earth April 19, 2002. STS-110's Extravehicular Activity (EVA) marked the first use of the Station's robotic arm to maneuver spacewalkers around the Station.

  1. Charge-transport model for conducting polymers

    Science.gov (United States)

    Dongmin Kang, Stephen; Jeffrey Snyder, G.

    2016-11-01

    The growing technological importance of conducting polymers makes the fundamental understanding of their charge transport extremely important for materials and process design. Various hopping and mobility edge transport mechanisms have been proposed, but their experimental verification is limited to poor conductors. Now that advanced organic and polymer semiconductors have shown high conductivity approaching that of metals, the transport mechanism should be discernible by modelling the transport like a semiconductor with a transport edge and a transport parameter s. Here we analyse the electrical conductivity and Seebeck coefficient together and determine that most polymers (except possibly PEDOT:tosylate) have s = 3 and thermally activated conductivity, whereas s = 1 and itinerant conductivity is typically found in crystalline semiconductors and metals. The different transport in polymers may result from the percolation of charge carriers from conducting ordered regions through poorly conducting disordered regions, consistent with what has been expected from structural studies.

  2. SATURATED ZONE FLOW AND TRANSPORT MODEL ABSTRACTION

    Energy Technology Data Exchange (ETDEWEB)

    B.W. ARNOLD

    2004-10-27

    The purpose of the saturated zone (SZ) flow and transport model abstraction task is to provide radionuclide-transport simulation results for use in the total system performance assessment (TSPA) for license application (LA) calculations. This task includes assessment of uncertainty in parameters that pertain to both groundwater flow and radionuclide transport in the models used for this purpose. This model report documents the following: (1) The SZ transport abstraction model, which consists of a set of radionuclide breakthrough curves at the accessible environment for use in the TSPA-LA simulations of radionuclide releases into the biosphere. These radionuclide breakthrough curves contain information on radionuclide-transport times through the SZ. (2) The SZ one-dimensional (I-D) transport model, which is incorporated in the TSPA-LA model to simulate the transport, decay, and ingrowth of radionuclide decay chains in the SZ. (3) The analysis of uncertainty in groundwater-flow and radionuclide-transport input parameters for the SZ transport abstraction model and the SZ 1-D transport model. (4) The analysis of the background concentration of alpha-emitting species in the groundwater of the SZ.

  3. Estimating Cosmological Parameter Covariance

    CERN Document Server

    Taylor, Andy

    2014-01-01

    We investigate the bias and error in estimates of the cosmological parameter covariance matrix, due to sampling or modelling the data covariance matrix, for likelihood width and peak scatter estimators. We show that these estimators do not coincide unless the data covariance is exactly known. For sampled data covariances, with Gaussian distributed data and parameters, the parameter covariance matrix estimated from the width of the likelihood has a Wishart distribution, from which we derive the mean and covariance. This mean is biased and we propose an unbiased estimator of the parameter covariance matrix. Comparing our analytic results to a numerical Wishart sampler of the data covariance matrix we find excellent agreement. An accurate ansatz for the mean parameter covariance for the peak scatter estimator is found, and we fit its covariance to our numerical analysis. The mean is again biased and we propose an unbiased estimator for the peak parameter covariance. For sampled data covariances the width estimat...

  4. Multi-Fraction Bayesian Sediment Transport Model

    Directory of Open Access Journals (Sweden)

    Mark L. Schmelter

    2015-09-01

    Full Text Available A Bayesian approach to sediment transport modeling can provide a strong basis for evaluating and propagating model uncertainty, which can be useful in transport applications. Previous work in developing and applying Bayesian sediment transport models used a single grain size fraction or characterized the transport of mixed-size sediment with a single characteristic grain size. Although this approach is common in sediment transport modeling, it precludes the possibility of capturing processes that cause mixed-size sediments to sort and, thereby, alter the grain size available for transport and the transport rates themselves. This paper extends development of a Bayesian transport model from one to k fractional dimensions. The model uses an existing transport function as its deterministic core and is applied to the dataset used to originally develop the function. The Bayesian multi-fraction model is able to infer the posterior distributions for essential model parameters and replicates predictive distributions of both bulk and fractional transport. Further, the inferred posterior distributions are used to evaluate parametric and other sources of variability in relations representing mixed-size interactions in the original model. Successful OPEN ACCESS J. Mar. Sci. Eng. 2015, 3 1067 development of the model demonstrates that Bayesian methods can be used to provide a robust and rigorous basis for quantifying uncertainty in mixed-size sediment transport. Such a method has heretofore been unavailable and allows for the propagation of uncertainty in sediment transport applications.

  5. EBS Radionuclide Transport Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    R. Schreiner

    2001-06-27

    The purpose of this work is to develop the Engineered Barrier System (EBS) radionuclide transport abstraction model, as directed by a written development plan (CRWMS M&O 1999a). This abstraction is the conceptual model that will be used to determine the rate of release of radionuclides from the EBS to the unsaturated zone (UZ) in the total system performance assessment-license application (TSPA-LA). In particular, this model will be used to quantify the time-dependent radionuclide releases from a failed waste package (WP) and their subsequent transport through the EBS to the emplacement drift wall/UZ interface. The development of this conceptual model will allow Performance Assessment Operations (PAO) and its Engineered Barrier Performance Department to provide a more detailed and complete EBS flow and transport abstraction. The results from this conceptual model will allow PA0 to address portions of the key technical issues (KTIs) presented in three NRC Issue Resolution Status Reports (IRSRs): (1) the Evolution of the Near-Field Environment (ENFE), Revision 2 (NRC 1999a), (2) the Container Life and Source Term (CLST), Revision 2 (NRC 1999b), and (3) the Thermal Effects on Flow (TEF), Revision 1 (NRC 1998). The conceptual model for flow and transport in the EBS will be referred to as the ''EBS RT Abstraction'' in this analysis/modeling report (AMR). The scope of this abstraction and report is limited to flow and transport processes. More specifically, this AMR does not discuss elements of the TSPA-SR and TSPA-LA that relate to the EBS but are discussed in other AMRs. These elements include corrosion processes, radionuclide solubility limits, waste form dissolution rates and concentrations of colloidal particles that are generally represented as boundary conditions or input parameters for the EBS RT Abstraction. In effect, this AMR provides the algorithms for transporting radionuclides using the flow geometry and radionuclide concentrations

  6. An Approach for Economic Analysis of Intermodal Transportation

    Directory of Open Access Journals (Sweden)

    Bahri Sahin

    2014-01-01

    Full Text Available A different intermodal transportation model based on cost analysis considering technical, economical, and operational parameters is presented. The model consists of such intermodal modes as sea-road, sea-railway, road-railway, and multimode of sea-road-railway. A case study of cargo transportation has been carried out by using the suggested model. Then, the single road transportation mode has been compared to intermodal modes in terms of transportation costs. This comparison takes into account the external costs of intermodal transportation. The research reveals that, in the short distance transportation, single transportation modes always tend to be advantageous. As the transportation distance gets longer, intermodal transportation advantages begin to be effective on the costs. In addition, the proposed method in this study leads to determining the fleet size and capacity for transportation and the appropriate transportation mode.

  7. An approach for economic analysis of intermodal transportation.

    Science.gov (United States)

    Sahin, Bahri; Yilmaz, Huseyin; Ust, Yasin; Guneri, Ali Fuat; Gulsun, Bahadir; Turan, Eda

    2014-01-01

    A different intermodal transportation model based on cost analysis considering technical, economical, and operational parameters is presented. The model consists of such intermodal modes as sea-road, sea-railway, road-railway, and multimode of sea-road-railway. A case study of cargo transportation has been carried out by using the suggested model. Then, the single road transportation mode has been compared to intermodal modes in terms of transportation costs. This comparison takes into account the external costs of intermodal transportation. The research reveals that, in the short distance transportation, single transportation modes always tend to be advantageous. As the transportation distance gets longer, intermodal transportation advantages begin to be effective on the costs. In addition, the proposed method in this study leads to determining the fleet size and capacity for transportation and the appropriate transportation mode.

  8. Next Generation Transport Phenomenology Model

    Science.gov (United States)

    Strickland, Douglas J.; Knight, Harold; Evans, J. Scott

    2004-01-01

    This report describes the progress made in Quarter 3 of Contract Year 3 on the development of Aeronomy Phenomenology Modeling Tool (APMT), an open-source, component-based, client-server architecture for distributed modeling, analysis, and simulation activities focused on electron and photon transport for general atmospheres. In the past quarter, column emission rate computations were implemented in Java, preexisting Fortran programs for computing synthetic spectra were embedded into APMT through Java wrappers, and work began on a web-based user interface for setting input parameters and running the photoelectron and auroral electron transport models.

  9. Chamber transport for heavy ion fusion

    Energy Technology Data Exchange (ETDEWEB)

    Olson, Craig L., E-mail: clolson66@msn.com

    2014-01-01

    A brief review is given of research on chamber transport for HIF (heavy ion fusion) dating from the first HIF Workshop in 1976 to the present. Chamber transport modes are categorized into ballistic transport modes and channel-like modes. Four major HIF reactor studies are summarized (HIBALL-II, HYLIFE-II, Prometheus-H, OSIRIS), with emphasis on the chamber transport environment. In general, many beams are used to provide the required symmetry and to permit focusing to the required small spots. Target parameters are then discussed, with a summary of the individual heavy ion beam parameters required for HIF. The beam parameters are then classified as to their line charge density and perveance, with special emphasis on the perveance limits for radial space charge spreading, for the space charge limiting current, and for the magnetic (Alfven) limiting current. The major experiments on ballistic transport (SFFE, Sabre beamlets, GAMBLE II, NTX, NDCX) are summarized, with specific reference to the axial electron trapping limit for charge neutralization. The major experiments on channel-like transport (GAMBLE II channel, GAMBLE II self-pinch, LBNL channels, GSI channels) are discussed. The status of current research on HIF chamber transport is summarized, and the value of future NDCX-II transport experiments for the future of HIF is noted.

  10. Biological transportation networks: Modeling and simulation

    KAUST Repository

    Albi, Giacomo

    2015-09-15

    We present a model for biological network formation originally introduced by Cai and Hu [Adaptation and optimization of biological transport networks, Phys. Rev. Lett. 111 (2013) 138701]. The modeling of fluid transportation (e.g., leaf venation and angiogenesis) and ion transportation networks (e.g., neural networks) is explained in detail and basic analytical features like the gradient flow structure of the fluid transportation network model and the impact of the model parameters on the geometry and topology of network formation are analyzed. We also present a numerical finite-element based discretization scheme and discuss sample cases of network formation simulations.

  11. Lumped-parameter models

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo; Liingaard, Morten

    A lumped-parameter model represents the frequency dependent soil-structure interaction of a massless foundation placed on or embedded into an unbounded soil domain. The lumped-parameter model development have been reported by (Wolf 1991b; Wolf 1991a; Wolf and Paronesso 1991; Wolf and Paronesso 19...

  12. Transport numbers in transdermal iontophoresis.

    Science.gov (United States)

    Mudry, Blaise; Guy, Richard H; Delgado-Charro, M Begoña

    2006-04-15

    Parameters determining ionic transport numbers in transdermal iontophoresis have been characterized. The transport number of an ion (its ability to carry charge) is key to its iontophoretic delivery or extraction across the skin. Using small inorganic ions, the roles of molar fraction and mobility of the co- and counterions present have been demonstrated. A direct, constant current was applied across mammalian skin in vitro. Cations were anodally delivered from either simple M(+)Cl(-) solutions (single-ion case, M(+) = sodium, lithium, ammonium, potassium), or binary and quaternary mixtures thereof. Transport numbers were deduced from ion fluxes. In the single-ion case, maximum cationic fluxes directly related to the corresponding ionic aqueous mobilities were found. Addition of co-ions decreased the transport numbers of all cations relative to the single-ion case, the degree of effect depending upon the molar fraction and mobility of the species involved. With chloride as the principal counterion competing to carry current across the skin (the in vivo situation), a maximum limit on the single or collective cation transport number was 0.6-0.8. Overall, these results demonstrate how current flowing across the skin during transdermal iontophoresis is distributed between competing ions, and establish simple rules with which to optimize transdermal iontophoretic transport.

  13. Robotic transportation.

    Science.gov (United States)

    Lob, W S

    1990-09-01

    Mobile robots perform fetch-and-carry tasks autonomously. An intelligent, sensor-equipped mobile robot does not require dedicated pathways or extensive facility modification. In the hospital, mobile robots can be used to carry specimens, pharmaceuticals, meals, etc. between supply centers, patient areas, and laboratories. The HelpMate (Transitions Research Corp.) mobile robot was developed specifically for hospital environments. To reach a desired destination, Help-Mate navigates with an on-board computer that continuously polls a suite of sensors, matches the sensor data against a pre-programmed map of the environment, and issues drive commands and path corrections. A sender operates the robot with a user-friendly menu that prompts for payload insertion and desired destination(s). Upon arrival at its selected destination, the robot prompts the recipient for a security code or physical key and awaits acknowledgement of payload removal. In the future, the integration of HelpMate with robot manipulators, test equipment, and central institutional information systems will open new applications in more localized areas and should help overcome difficulties in filling transport staff positions.

  14. Chemical transport reactions

    CERN Document Server

    Schäfer, Harald

    2013-01-01

    Chemical Transport Reactions focuses on the processes and reactions involved in the transport of solid or liquid substances to form vapor phase reaction products. The publication first offers information on experimental and theoretical principles and the transport of solid substances and its special applications. Discussions focus on calculation of the transport effect of heterogeneous equilibria for a gas motion between equilibrium spaces; transport effect and the thermodynamic quantities of the transport reaction; separation and purification of substances by means of material transport; and

  15. Peritoneal Fluid Transport rather than Peritoneal Solute Transport Associates with Dialysis Vintage and Age of Peritoneal Dialysis Patients

    Directory of Open Access Journals (Sweden)

    Jacek Waniewski

    2016-01-01

    Full Text Available During peritoneal dialysis (PD, the peritoneal membrane undergoes ageing processes that affect its function. Here we analyzed associations of patient age and dialysis vintage with parameters of peritoneal transport of fluid and solutes, directly measured and estimated based on the pore model, for individual patients. Thirty-three patients (15 females; age 60 (21–87 years; median time on PD 19 (3–100 months underwent sequential peritoneal equilibration test. Dialysis vintage and patient age did not correlate. Estimation of parameters of the two-pore model of peritoneal transport was performed. The estimated fluid transport parameters, including hydraulic permeability (LpS, fraction of ultrasmall pores (αu, osmotic conductance for glucose (OCG, and peritoneal absorption, were generally independent of solute transport parameters (diffusive mass transport parameters. Fluid transport parameters correlated whereas transport parameters for small solutes and proteins did not correlate with dialysis vintage and patient age. Although LpS and OCG were lower for older patients and those with long dialysis vintage, αu was higher. Thus, fluid transport parameters—rather than solute transport parameters—are linked to dialysis vintage and patient age and should therefore be included when monitoring processes linked to ageing of the peritoneal membrane.

  16. METHODS OF INTEGRATED OPTIMIZATION MAGLEV TRANSPORT SYSTEMS

    Directory of Open Access Journals (Sweden)

    A. Lasher

    2013-09-01

    Full Text Available Purpose. To demonstrate feasibility of the proposed integrated optimization of various MTS parameters to reduce capital investments as well as decrease any operational and maintenance expense. This will make use of MTS reasonable. At present, the Maglev Transport Systems (MTS for High-Speed Ground Transportation (HSGT almost do not apply. Significant capital investments, high operational and maintenance costs are the main reasons why Maglev Transport Systems (MTS are hardly currently used for the High-Speed Ground Transportation (HSGT. Therefore, this article justifies use of Theory of Complex Optimization of Transport (TCOT, developed by one of the co-authors, to reduce MTS costs. Methodology. According to TCOT, authors developed an abstract model of the generalized transport system (AMSTG. This model mathematically determines the optimal balance between all components of the system and thus provides the ultimate adaptation of any transport systems to the conditions of its application. To identify areas for effective use of MTS, by TCOT, the authors developed a dynamic model of distribution and expansion of spheres of effective use of transport systems (DMRRSEPTS. Based on this model, the most efficient transport system was selected for each individual track. The main estimated criterion at determination of efficiency of application of MTS is the size of the specific transportation tariff received from calculation of payback of total given expenses to a standard payback period or term of granting the credit. Findings. The completed multiple calculations of four types of MTS: TRANSRAPID, MLX01, TRANSMAG and TRANSPROGRESS demonstrated efficiency of the integrated optimization of the parameters of such systems. This research made possible expending the scope of effective usage of MTS in about 2 times. The achieved results were presented at many international conferences in Germany, Switzerland, United States, China, Ukraine, etc. Using MTS as an

  17. 千米深井复杂运输条件特厚煤层综放支架设计及参数优化%Design and Parameters Optimization of Full-mechanized Top-coal Caving Powered Support for Extremely-thick Coal-seam under Complex Transportation Condition in 1000 m Deep Mine

    Institute of Scientific and Technical Information of China (English)

    张金虎

    2015-01-01

    为满足3号特厚煤层千米以上埋深、顶板控制要求和复杂运输条件,对不同采煤方法适应性和支架参数进行研究。研究结果表明:特厚煤层综放开采在回采率、成本控制、安全保障和设备配套等方面较分层和大采高综采具有较大优势,千米埋深特厚煤层所需支护强度为1.3~1.4MPa,支架设计ϕ300/220mm较大缸径立柱和1500mm较小中心距解决罐笼小尺寸运输和强力支护重型大设备之间的矛盾,采用铰接顶梁加强架前支护和方便运输,优化立柱布置保证足够的行人和操作空间,设置防倒防滑、双侧活动侧护板和抬底机构增强对较大倾角和较软底板的适应性。%In order to meet 1000m deep depth, roof controlling requirement and complex transportation condition of No. 3 extremely-thick coalseam, adaptability of different mining methods and powered support's parameters were researched. Results showed that full-mechanized top-coal caving mining had larger advantage in mining ratio, cost control, safety assurance and equipments matching, compared with slicing mining and large-mining-height full-mechanized mining method. For extremely-thick coalseam in 1000m deep mine, 1. 3-1. 4MPa supporting intensity, 300/220 cylinder diameter and 1500mm center distance was designed to solve the conflict of small size cage and large equipment. Articulated roof beam was applied to strengthening supporting and facilitating transportation. Prop arrangement was optimized to ensure enough pedestrian and operation space. Anti-slide and anti-dumping structure, side-guard plate and bottom-lift device was designed to strengthen adaptability for large inclined angle and soft floor.

  18. Supersymmetry Parameter Analysis

    CERN Document Server

    Kalinowski, Jan

    2002-01-01

    Supersymmetric particles can be produced copiously at future colliders. From the high-precision data taken at e+e- linear colliders, TESLA in particular, and combined with results from LHC, and CLIC later, the low-energy parameters of the supersymmetric model can be determined. Evolving the parameters from the low-energy scale to the high-scale by means of renormalization group techniques the fundamental supersymmetry parameters at the high scale, GUT or Planck, can be reconstructed to reveal the origin of supersymmetry breaking.

  19. Magnetic S-parameter

    DEFF Research Database (Denmark)

    Sannino, Francesco

    2010-01-01

    We propose a direct test of the existence of gauge duals for nonsupersymmetric asymptotically free gauge theories developing an infrared fixed point by computing the S-parameter in the electric and dual magnetic description. In particular we show that at the lower bound of the conformal window...... the magnetic S-parameter, i.e. the one determined via the dual magnetic gauge theory, assumes a simple expression in terms of the elementary magnetic degrees of freedom. The results further support our recent conjecture of the existence of a universal lower bound on the S parameter and indicates...

  20. Transporting particulate material

    Science.gov (United States)

    Aldred, Derek Leslie [North Hollywood, CA; Rader, Jeffrey A [North Hollywood, CA; Saunders, Timothy W [North Hollywood, CA

    2011-08-30

    A material transporting system comprises a material transporting apparatus (100) including a material transporting apparatus hopper structure (200, 202), which comprises at least one rotary transporting apparatus; a stationary hub structure (900) constraining and assisting the at least one rotary transporting apparatus; an outlet duct configuration (700) configured to permit material to exit therefrom and comprising at least one diverging portion (702, 702'); an outlet abutment configuration (800) configured to direct material to the outlet duct configuration; an outlet valve assembly from the material transporting system venting the material transporting system; and a moving wall configuration in the material transporting apparatus capable of assisting the material transporting apparatus in transporting material in the material transporting system. Material can be moved from the material transporting apparatus hopper structure to the outlet duct configuration through the at least one rotary transporting apparatus, the outlet abutment configuration, and the outlet valve assembly.

  1. Plant Transporter Identification

    DEFF Research Database (Denmark)

    Larsen, Bo

    Membrane transport proteins (transporters) play a critical role for numerous biological processes, by controlling the movements of ions and molecules in and out of cells. In plants, transporters thus function as gatekeepers between the plant and its surrounding environment and between organs......, tissues, cells and intracellular compartments. Since plants are highly compartmentalized organisms with complex transportation infrastructures, they consequently have many transporters. However, the vast majority of predicted transporters have not yet been experimentally verified to have transport...... activity. This project contains a review of the implemented methods, which have led to plant transporter identification, and present our progress on creating a high-throughput functional genomics transporter identification platform....

  2. Plant Transporter Identification

    DEFF Research Database (Denmark)

    Larsen, Bo

    Membrane transport proteins (transporters) play a critical role for numerous biological processes, by controlling the movements of ions and molecules in and out of cells. In plants, transporters thus function as gatekeepers between the plant and its surrounding environment and between organs......, tissues, cells and intracellular compartments. Since plants are highly compartmentalized organisms with complex transportation infrastructures, they consequently have many transporters. However, the vast majority of predicted transporters have not yet been experimentally verified to have transport...... activity. This project contains a review of the implemented methods, which have led to plant transporter identification, and present our progress on creating a high-throughput functional genomics transporter identification platform....

  3. Transportation and the environment.

    NARCIS (Netherlands)

    Banister, D.; Anderton, K.; Bonilla, D.; Givoni, M.; Schwanen, T.

    2011-01-01

    The growth of CO2-intensive transport, mobility and the impact of transport on the environment are reviewed. The recent global exponential growth in transport is unsustainable and must end unless the transport sector can decarbonize. The paper examines solutions for low-carbon transport systems; the

  4. Transport properties of ceramic composites

    Energy Technology Data Exchange (ETDEWEB)

    Starr, T.L.; Hablutzel, N. [Georgia Institute of Technology, Atlanta, GA (United States)

    1996-08-01

    Instrumentation and procedures have been completed for measurement of gas permeability and mass diffusivity of fiber preforms and porous materials. Results are reported for composites reinforced with Nicalon fiber in cloth lay-up and 3-D weave and with Nextel fiber in multi-layer braid. Measured permeability values range from near 100 to less than 0.1 darcies. Mass diffusivity is reported as a structure factor relating the diffusion through the porous material to that in free space. This measure is independent of the diffusing species and depends only on the pore structure of the material. Measurements are compared to predictions of a node-bond model for gas transport. Model parameters adjusted to match measured transport properties relate to physical microstructure features of the different architectures. Combination of this transport model with the CVI process model offers a predictive method to evaluate the densification behavior of various fiber preforms.

  5. Random Access Transport Capacity

    CERN Document Server

    Andrews, Jeffrey G; Kountouris, Marios; Haenggi, Martin

    2009-01-01

    We develop a new metric for quantifying end-to-end throughput in multihop wireless networks, which we term random access transport capacity, since the interference model presumes uncoordinated transmissions. The metric quantifies the average maximum rate of successful end-to-end transmissions, multiplied by the communication distance, and normalized by the network area. We show that a simple upper bound on this quantity is computable in closed-form in terms of key network parameters when the number of retransmissions is not restricted and the hops are assumed to be equally spaced on a line between the source and destination. We also derive the optimum number of hops and optimal per hop success probability and show that our result follows the well-known square root scaling law while providing exact expressions for the preconstants as well. Numerical results demonstrate that the upper bound is accurate for the purpose of determining the optimal hop count and success (or outage) probability.

  6. Flow and transport in the drift shadow in a dual-continuum model

    Energy Technology Data Exchange (ETDEWEB)

    Houseworth, J.E.; Finsterle, S.; Bodvarsson, G.S.

    2002-09-01

    The current concept for high-level radioactive waste disposal at Yucca Mountain is for the waste to be placed in underground tunnels (or drifts) in the middle of a thick unsaturated zone. Flow modeling and field testing have shown that not all flow encountering a drift will seep into the drift. The underlying reason for the diversion of unsaturated flow around a drift is that capillary forces in the fractures and matrix prevent water entry into the drift unless the capillary pressure in the rock decreases sufficiently to allow for gravity forces to overcome the capillary barrier. As a result of the capillary barrier effect, flow tends to be diverted around the drift, affecting the flow pattern beneath the drift. For some distance beneath the drift, water saturation and flux are reduced. This drift shadow zone is much more pronounced in the fractures than in the matrix due to dominance of gravity over capillary forces in the fractures. Moving downward, away from the drift, the shadow zone asymptotically re-equilibrates to the undisturbed flow conditions due to capillary forces. The behavior of radionuclide transport in this zone of reduced flow is investigated here because this will affect the amount of time required for radionuclides to penetrate the unsaturated zone. The delay of radio nuclide movement in the geosphere is one aspect of the potential repository system that could limit public exposure to radioactive waste. The behavior of flow and transport are calculated using a two-dimensional, drift-scale dual permeability model extending to nine drift diameters below the potential waste emplacement drift. The flow model is first compared with an analytical model for a single-continuum. Then the dual-continuum flow model is investigated with respect to drift-scale and mountain-scale property sets. Transport calculations are performed for a wide range of flow conditions and for different aqueous radionuclides and colloids. Findings indicate that transport times

  7. Road Transport Entrepreneurs and Road Transportation Revolution ...

    African Journals Online (AJOL)

    Toshiba

    An International Multidisciplinary Journal, Ethiopia. Vol. 7 (4), Serial No. ... Nnewi Igbo emerged as pioneer road transport entrepreneurs and charted this novel ..... the cardinal motives for venturing into the transport industry. (Maduewesi ...

  8. The Advanced Photon Source list of parameters

    Energy Technology Data Exchange (ETDEWEB)

    Bizek, H.M. [comp.

    1996-07-01

    The Advanced Photon Source (APS) is a third-generation synchrotron radiation source that stores positrons in a storage ring. The choice of positrons as accelerating particles was motivated by the usual reason: to eliminate the degradation of the beam caused by trapping of positively charged dust particles or ions. The third-generation synchrotron radiation sources are designed to have low beam emittance and many straight sections for insertion devices. The parameter list is comprised of three basic systems: the injection system, the storage ring system, and the experimental facilities system. The components of the injection system are listed according to the causal flow of positrons. Below we briefly list the individual components of the injection system, with the names of people responsible for managing these machines in parentheses: the linac system; electron linac-target-positron linac (Marion White); low energy transport line from linac to the PAR (Michael Borland); positron accumulator ring or PAR (Michael Borland); low energy transport line from PAR to injector synchrotron (Michael Borland); injector synchrotron (Stephen Milton); high energy transport line from injector synchrotron to storage ring (Stephen Milton). The storage ring system, managed by Glenn Decker, uses the Chasman-Green lattice. The APS storage ring, 1104 m in circumference, has 40 periodic sectors. Six are used to house hardware and 34 serve as insertion devices. Another 34 beamlines emit radiation from bending magnets. The experimental facilities system`s parameters include parameters for both an undulator and a wiggler.

  9. Saxton Transportation Operations Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Saxton Transportation Operations Laboratory (Saxton Laboratory) is a state-of-the-art facility for conducting transportation operations research. The laboratory...

  10. Smart Growth and Transportation

    Science.gov (United States)

    Describes the relationship between smart growth and transportation, focusing smart and sustainable street design, transit-oriented development, parking management, sustainable transportation planning, and related resources.

  11. Expanding the role of reactive transport models in critical zone processes

    Science.gov (United States)

    Li, Li; Maher, Kate; Navarre-Sitchler, Alexis; Druhan, Jennifer; Meile, Christof; Lawrence, Corey; Moore, Joel; Perdrial, Julia; Sullivan, Pamela; Thompson, Aaron; Jin, Lixin; Bolton, Edward W.; Brantley, Susan L.; Dietrich, William E.; Mayer, K. Ulrich; Steefel, Carl; Valocchi, Albert J.; Zachara, John M.; Kocar, Benjamin D.; McIntosh, Jennifer; Tutolo, Benjamin M.; Kumar, Mukesh; Sonnenthal, Eric; Bao, Chen; Beisman, Joe

    2017-01-01

    Models test our understanding of processes and can reach beyond the spatial and temporal scales of measurements. Multi-component Reactive Transport Models (RTMs), initially developed more than three decades ago, have been used extensively to explore the interactions of geothermal, hydrologic, geochemical, and geobiological processes in subsurface systems. Driven by extensive data sets now available from intensive measurement efforts, there is a pressing need to couple RTMs with other community models to explore non-linear interactions among the atmosphere, hydrosphere, biosphere, and geosphere. Here we briefly review the history of RTM development, summarize the current state of RTM approaches, and identify new research directions, opportunities, and infrastructure needs to broaden the use of RTMs. In particular, we envision the expanded use of RTMs in advancing process understanding in the Critical Zone, the veneer of the Earth that extends from the top of vegetation to the bottom of groundwater. We argue that, although parsimonious models are essential at larger scales, process-based models offer tools to explore the highly nonlinear coupling that characterizes natural systems. We present seven testable hypotheses that emphasize the unique capabilities of process-based RTMs for (1) elucidating chemical weathering and its physical and biogeochemical drivers; (2) understanding the interactions among roots, micro-organisms, carbon, water, and minerals in the rhizosphere; (3) assessing the effects of heterogeneity across spatial and temporal scales; and (4) integrating the vast quantity of novel data, including “omics” data (genomics, transcriptomics, proteomics, metabolomics), elemental concentration and speciation data, and isotope data into our understanding of complex earth surface systems. With strong support from data-driven sciences, we are now in an exciting era where integration of RTM framework into other community models will facilitate process

  12. Revisiting Cosmological parameter estimation

    CERN Document Server

    Prasad, Jayanti

    2014-01-01

    Constraining theoretical models with measuring the parameters of those from cosmic microwave background (CMB) anisotropy data is one of the most active areas in cosmology. WMAP, Planck and other recent experiments have shown that the six parameters standard $\\Lambda$CDM cosmological model still best fits the data. Bayesian methods based on Markov-Chain Monte Carlo (MCMC) sampling have been playing leading role in parameter estimation from CMB data. In one of the recent studies \\cite{2012PhRvD..85l3008P} we have shown that particle swarm optimization (PSO) which is a population based search procedure can also be effectively used to find the cosmological parameters which are best fit to the WMAP seven year data. In the present work we show that PSO not only can find the best-fit point, it can also sample the parameter space quite effectively, to the extent that we can use the same analysis pipeline to process PSO sampled points which is used to process the points sampled by Markov Chains, and get consistent res...

  13. Parameter Estimation Through Ignorance

    CERN Document Server

    Du, Hailiang

    2015-01-01

    Dynamical modelling lies at the heart of our understanding of physical systems. Its role in science is deeper than mere operational forecasting, in that it allows us to evaluate the adequacy of the mathematical structure of our models. Despite the importance of model parameters, there is no general method of parameter estimation outside linear systems. A new relatively simple method of parameter estimation for nonlinear systems is presented, based on variations in the accuracy of probability forecasts. It is illustrated on the Logistic Map, the Henon Map and the 12-D Lorenz96 flow, and its ability to outperform linear least squares in these systems is explored at various noise levels and sampling rates. As expected, it is more effective when the forecast error distributions are non-Gaussian. The new method selects parameter values by minimizing a proper, local skill score for continuous probability forecasts as a function of the parameter values. This new approach is easier to implement in practice than alter...

  14. MSSM without free parameters

    Science.gov (United States)

    Kitano, Ryuichiro; Motono, Ryuji; Nagai, Minoru

    2016-12-01

    It is often argued that the minimal supersymmetric standard model has O (100 ) free parameters, and the generic parameter region is already excluded by the null observation of the flavor and C P -violating processes as well as the constraints from the LHC experiments. This situation naturally leads us to consider the case where all the dangerous soft supersymmetry breaking terms, such as the scalar masses and scalar couplings, are absent, while only the unified gaugino mass term and the μ term are nonvanishing at the grand unification scale. We revisit this simple situation taking into account the observed Higgs boson mass, 125 GeV. Since the gaugino mass and the μ term are fixed in order to explain the Higgs boson and the Z boson masses, there is no free parameter left in this scenario. We find that there are three independent parameter sets that exist including ones which have not been discussed in the literature. We also find that the abundance of the dark matter can be explained by relic gravitinos which are nonthermally produced as decay products of the supersymmetry particles while satisfying constraints from big bang nucleosynthesis. We discuss the effects of the gravity mediation which generically gives a contribution to the soft terms of the order of the gravitino mass. It turns out that a newly found parameter set is preferable to explain the Higgs boson mass as well as the gravitino dark matter while satisfying the constraints from the electric dipole moments of the electron and the nucleon.

  15. Fundamental stellar parameters

    CERN Document Server

    Wittkowski, M

    2004-01-01

    I present a discussion of fundamental stellar parameters and their observational determination in the context of interferometric measurements with current and future optical/infrared interferometric facilities. Stellar parameters and the importance of their determination for stellar physics are discussed. One of the primary uses of interferometry in the field of stellar physics is the measurement of the intensity profile across the stellar disk, both as a function of position angle and of wavelength. High-precision fundamental stellar parameters are also derived by characterizations of binary and multiple system using interferometric observations. This topic is discussed in detail elsewhere in these proceedings. Comparison of observed spectrally dispersed center-to-limb intensity variations with models of stellar atmospheres and stellar evolution may result in an improved understanding of key phenomena in stellar astrophysics such as the precise evolutionary effects on the main sequence, the evolution of meta...

  16. Variations on tremor parameters

    Science.gov (United States)

    Boose, A.; Jentgens, Ch.; Spieker, S.; Dichgans, J.

    1995-03-01

    This paper describes our analysis procedure for long-term tremor EMG recordings, as well as three examples of applications. The description of the method focuses on how characteristics of the tremor (e.g. frequency, intensity, agonist-antagonist interaction) can be defined and calculated based on surface EMG data. The resulting quantitative characteristics are called ``tremor parameters.'' We discuss sinusoidally modulated, band-limited white noise as a model for pathological tremor-EMG, and show how the basic parameters can be extracted from this class of signals. The method is then applied to (1) estimate tremor severity in clinical studies, (2) quantify agonist-antagonist interaction, and (3) investigate the variations of the tremor parameters using simple methods from time-series analysis.

  17. Optomechanical parameter estimation

    CERN Document Server

    Ang, Shan Zheng; Bowen, Warwick P; Tsang, Mankei

    2013-01-01

    We propose a statistical framework for the problem of parameter estimation from a noisy optomechanical system. The Cram\\'er-Rao lower bound on the estimation errors in the long-time limit is derived and compared with the errors of radiometer and expectation-maximization (EM) algorithms in the estimation of the force noise power. When applied to experimental data, the EM estimator is found to have the lowest error and follow the Cram\\'er-Rao bound most closely. With its ability to estimate most of the system parameters, the EM algorithm is envisioned to be useful for optomechanical sensing, atomic magnetometry, and classical or quantum system identification applications in general.

  18. Degradation of concrete-based barriers by Mg-containing brines: From laboratory experiments via reactive transport modelling to overall safety analysis in repository scale

    Science.gov (United States)

    Niemeyer, Matthias; Wilhelm, Stefan; Hagemann, Sven; Xie, Mingliang; Wollrath, Jürgen; Preuss, Jürgen

    2010-05-01

    initial hydraulic permeability and possibly on inhomogeneities like fractures and the hydraulic behaviour of the excavation damage zone (EDZ). Experimentally, the corrosion capacity of the brines to the concrete cannot be directly determined by throughflow experiments because the initial hydraulic permeability of the original building material is far too low. Instead, the decrease of magnesium, the main corroding agent in the brines, has been measured in cascade experiments with grounded cement mortar. The results of these experiments have been reproduced with geochemical modelling. However, those model calculations reveal that the stoichiometry of this reaction strongly depends on the assumptions about the relative stability of the potentially formed mineral phases, especially the various magnesium-silicate-hydrate-phases. As a pragmatic approach, the probability density function of the corrosion capacity has been estimated by stochastic calculations including the variation within a reasonable bandwidth of the chemical composition of each mortar components and the thermodynamic data of the critical mineral phases. Subsequently, the corrosion of the sealed access drifts in repository scale has been simulated by a reactive transport model, combining advective / dispersive transport and variable hydraulic permeability as function of the reaction progress. In the model, the chemistry of the corrosion process has been abstracted to one single equation. This allowed a fine discretisation - more than 10'000 nodes in an auto-adapting 2D-FE-mesh with axial symmetry. The parameter for the reaction rate was chosen on basis of experimental observations and turned out to be non-sensitive. The calculations show that the reaction zone is quite narrow - less than 5 m in a seal of 130 m length - as the reaction rate is much faster than the transport processes. With this model, the influence of a persistent EDZ in the host rock on the degradation of the hydraulic seal was studied

  19. Potential wine ageing during transportation

    Directory of Open Access Journals (Sweden)

    Jung Rainer

    2014-01-01

    Full Text Available In a global world, wineries have to satisfy the demand of consumers who wish to drink high quality wines from countries all over the world. To fulfill this request wines have to be transported, crossing thereby great distances from the place of production to the consumer country. At the Institute of Enology of Hochschule Geisenheim University examinations with White-, Rosé- and Red-Wines of different origins which had been transported over longer distances within Europe (Portugal, France, Italy to Germany by trucks were carried out. Shipping of wines was simulated in a climatized cabinet to analyze the influence on wine quality during this way and conditions of transportation. Time and temperature profiles were based on real transport situtations which were recorded during shipping from Germany to Japan using data loggers. White, Rosé and Red wines were transported during 6 to 8 weeks and then were analytically and sensorically compared to those which were stored at a constant temperature of 15 ∘C. Besides the effect of temperature, the movements and vibrations encountered by the wines were also examined. Analytically wines were analyzed for general analytical parameters with Fourier-Transformation-Infrared-Spectroscopie (FTIR, Colour differences (Spectralphotometrie and free and total sulfuric acid with Flow-Injection-Analysis (FIA. Sensory examinations with a trained panel were performed in difference tests in form of rankings and triangular tests. Summarizing the results from the different tests it could be found that transportation had an influence on the potential ageing of wines depending on the wine matrix. Especially high and varying temperatures during transportations over a longer distance and time had negative influences on wine quality. Also the movement of wine at higher temperatures had showed a negative effect whereas transport at cool temperatures even below 0 ∘C did not influence wine characteristics. Sophisticated

  20. Railroad transportation of spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Wooden, D.G.

    1986-03-01

    This report documents a detailed analysis of rail operations that are important for assessing the risk of transporting high-level nuclear waste. The major emphasis of the discussion is towards ''general freight'' shipments of radioactive material. The purpose of this document is to provide a basis for selecting models and parameters that are appropriate for assessing the risk of rail transportation of nuclear waste.

  1. Electromagnetic Transport From Microtearing Mode Turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Guttenfelder, W; Kaye, S M; Nevins, W M; Wang, E; Bell, R E; Hammett, G W; LeBlanc, B P; Mikkelsen, D R

    2011-03-23

    This Letter presents non-linear gyrokinetic simulations of microtearing mode turbulence. The simulations include collisional and electromagnetic effects and use experimental parameters from a high beta discharge in the National Spherical Torus Experiment (NSTX). The predicted electron thermal transport is comparable to that given by experimental analysis, and it is dominated by the electromagnetic contribution of electrons free streaming along the resulting stochastic magnetic field line trajectories. Experimental values of flow shear can significantly reduce the predicted transport.

  2. Band parameters of phosphorene

    DEFF Research Database (Denmark)

    Lew Yan Voon, L. C.; Wang, J.; Zhang, Y.;

    2015-01-01

    Phosphorene is a two-dimensional nanomaterial with a direct band-gap at the Brillouin zone center. In this paper, we present a recently derived effective-mass theory of the band structure in the presence of strain and electric field, based upon group theory. Band parameters for this theory...

  3. Ovarian reserve parameters

    DEFF Research Database (Denmark)

    Bentzen, J G; Forman, Julie Lyng; Pinborg, Anja;

    2012-01-01

    was observed between duration of hormonal-contraception use and ovarian reserve parameters. No dose-response relation was found between the dose of ethinyloestradiol and AMH or AFC. This study indicates that ovarian reserve markers are lower in women using sex steroids for contraception. Thus, AMH...

  4. Response model parameter linking

    NARCIS (Netherlands)

    Barrett, Michelle Derbenwick

    2015-01-01

    With a few exceptions, the problem of linking item response model parameters from different item calibrations has been conceptualized as an instance of the problem of equating observed scores on different test forms. This thesis argues, however, that the use of item response models does not require

  5. Some issues of passenger choice of suburban transport mode

    Directory of Open Access Journals (Sweden)

    Тetyana М. Grigorova

    2015-06-01

    Full Text Available In this article the passenger choice of transport mode for moving to suburban is discussed. The analysis of methods of Transport Management in suburban transportation showed that they did not fully take into account the effect of the transport process parameters on the passenger choice of transport mode for travel. The aim of research is to determine the value of the factors that influence passenger choice of suburban transport. The study was conducted on the basis of passenger survey on the factors affecting the choice of transport mode, and the importance of these factors. Kendall's coefficient of concordance its statistical significance were used to evaluate the consistency of expert opinion. The main factors for choosing the mode of suburban transport are identified. The identified factors can then be used in determining selection patterns of suburban transport mode.

  6. Water-transporting proteins

    DEFF Research Database (Denmark)

    Zeuthen, Thomas

    2010-01-01

    Transport through lipids and aquaporins is osmotic and entirely driven by the difference in osmotic pressure. Water transport in cotransporters and uniporters is different: Water can be cotransported, energized by coupling to the substrate flux by a mechanism closely associated with protein...... transport. Epithelial water transport is energized by the movements of ions, but how the coupling takes place is uncertain. All epithelia can transport water uphill against an osmotic gradient, which is hard to explain by simple osmosis. Furthermore, genetic removal of aquaporins has not given support...... to osmosis as the exclusive mode of transport. Water cotransport can explain the coupling between ion and water transport, a major fraction of transepithelial water transport and uphill water transport. Aquaporins enhance water transport by utilizing osmotic gradients and cause the osmolarity...

  7. Electron transport in wurtzite InN

    Indian Academy of Sciences (India)

    F M Abou El-Ela; B M El-Assy

    2012-07-01

    Using ensemble Monte Carlo simulation technique, we have calculated the transport properties of InN such as the drift velocity, the drift mobility, the average electron, energy relaxation times and momentum relaxation times at high electric field. The scattering mechanisms included are polar optical phonon, ionized impurity, acoustic phonon and intervalley phonon. It is found that the maximum peak velocity only occurs when the electric field is increased to a value above a certain critical field. This critical field is strongly dependent on InN parameters. The steady-state transport parameters are in fair agreement with other recent calculations.

  8. Contaminant transport at a waste residue deposit

    DEFF Research Database (Denmark)

    Engesgaard, Peter Knudegaard; Traberg, Rikke

    1996-01-01

    Contaminant transport in an aquifer at an incinerator waste residue deposit in Denmark is simulated. A two-dimensional, geochemical transport code is developed for this purpose and tested by comparison to results from another code, The code is applied to a column experiment and to the field site...... along with the flow and nonreactive transport parameters obtained by the inverse modeling procedure described in the first paper [Sonnenborg et al., this issue] of this two-paper series. The simulation results of the site model are compared with several measured component breakthroughs at monitoring...

  9. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Stefan Miska; Nicholas Takach; Kaveh Ashenayi

    2004-01-31

    Final design of the mast was completed (Task 5). The mast is consisting of two welded plate girders, set next to each other, and spaced 14-inches apart. Fabrication of the boom will be completed in two parts solely for ease of transportation. The end pivot connection will be made through a single 2-inch diameter x 4 feet-8 inch long 316 SS bar. During installation, hard piping make-ups using Chiksan joints will connect the annular section and 4-inch return line to allow full movement of the mast from horizontal to vertical. Additionally, flexible hoses and piping will be installed to isolate both towers from piping loads and allow recycling operations respectively. Calibration of the prototype Foam Generator Cell has been completed and experiments are now being conducted. We were able to generate up to 95% quality foam. Work is currently underway to attach the Thermo-Haake RS300 viscometer and install a view port with a microscope to measure foam bubble size and bubble size distribution. Foam rheology tests (Task 13) were carried out to evaluate the rheological properties of the proposed foam formulation. After successful completion of the first foam test, two sets of rheological tests were conducted at different foam flow rates while keeping other parameters constant (100 psig, 70F, 80% quality). The results from these tests are generally in agreement with the previous foam tests done previously during Task 9. However, an unanticipated observation during these tests was that in both cases, the frictional pressure drop in 2 inch pipe was lower than that in the 3 inch and 4 inch pipes. We also conducted the first foam cuttings transport test during this quarter. Experiments on aerated fluids without cuttings have been completed in ACTF (Task 10). Gas and liquid were injected at different flow rates. Two different sets of experiments were carried out, where the only difference was the temperature. Another set of tests was performed, which covered a wide range of

  10. Distributed Parameter Modelling Applications

    DEFF Research Database (Denmark)

    2011-01-01

    Here the issue of distributed parameter models is addressed. Spatial variations as well as time are considered important. Several applications for both steady state and dynamic applications are given. These relate to the processing of oil shale, the granulation of industrial fertilizers and the d......Here the issue of distributed parameter models is addressed. Spatial variations as well as time are considered important. Several applications for both steady state and dynamic applications are given. These relate to the processing of oil shale, the granulation of industrial fertilizers...... sands processing. The fertilizer granulation model considers the dynamics of MAP-DAP (mono and diammonium phosphates) production within an industrial granulator, that involves complex crystallisation, chemical reaction and particle growth, captured through population balances. A final example considers...

  11. Physical Parameter Eclipse Mapping

    CERN Document Server

    Vrielmann, S

    2000-01-01

    The tomographic method "Physical Parameter Eclipse Mapping" is a tool to reconstruct spatial distributions of physical parameters (like temperatures and surface densities) in accretion discs of cataclysmic variables. After summarizing the method, we apply it to multi-colour eclipse light curves of various dwarf novae and nova-likes like VZ Scl, IP Peg in outburst, UU Aqr, V2051 Oph and HT Cas in order to derive the temperatures (and surface densities) in the disc, the white dwarf temperature, the disc size, the effective temperatures and the viscosities. The results allows us to establish or refine a physical model for the accretion disc. Our maps of HT Cas and V2051 Oph, for example, indicate that the (quiescent) disc must be structured into a cool, optically thick inner disc sandwiched by hot, optically thin chromospheres. In addition, the disc of HT Cas must be patchy with a covering factor of about 40% caused by magnetic activity in the disc.

  12. Setting Parameters by Example

    OpenAIRE

    1999-01-01

    We introduce a class of "inverse parametric optimization" problems, in which one is given both a parametric optimization problem and a desired optimal solution; the task is to determine parameter values that lead to the given solution. We describe algorithms for solving such problems for minimum spanning trees, shortest paths, and other "optimal subgraph" problems, and discuss applications in multicast routing, vehicle path planning, resource allocation, and board game programming.

  13. Military display performance parameters

    Science.gov (United States)

    Desjardins, Daniel D.; Meyer, Frederick

    2012-06-01

    The military display market is analyzed in terms of four of its segments: avionics, vetronics, dismounted soldier, and command and control. Requirements are summarized for a number of technology-driving parameters, to include luminance, night vision imaging system compatibility, gray levels, resolution, dimming range, viewing angle, video capability, altitude, temperature, shock and vibration, etc., for direct-view and virtual-view displays in cockpits and crew stations. Technical specifications are discussed for selected programs.

  14. Transport properties site descriptive model. Guidelines for evaluation and modelling

    Energy Technology Data Exchange (ETDEWEB)

    Berglund, Sten [WSP Environmental, Stockholm (Sweden); Selroos, Jan-Olof [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

    2004-04-01

    This report describes a strategy for the development of Transport Properties Site Descriptive Models within the SKB Site Investigation programme. Similar reports have been produced for the other disciplines in the site descriptive modelling (Geology, Hydrogeology, Hydrogeochemistry, Rock mechanics, Thermal properties, and Surface ecosystems). These reports are intended to guide the site descriptive modelling, but also to provide the authorities with an overview of modelling work that will be performed. The site descriptive modelling of transport properties is presented in this report and in the associated 'Strategy for the use of laboratory methods in the site investigations programme for the transport properties of the rock', which describes laboratory measurements and data evaluations. Specifically, the objectives of the present report are to: Present a description that gives an overview of the strategy for developing Site Descriptive Models, and which sets the transport modelling into this general context. Provide a structure for developing Transport Properties Site Descriptive Models that facilitates efficient modelling and comparisons between different sites. Provide guidelines on specific modelling issues where methodological consistency is judged to be of special importance, or where there is no general consensus on the modelling approach. The objectives of the site descriptive modelling process and the resulting Transport Properties Site Descriptive Models are to: Provide transport parameters for Safety Assessment. Describe the geoscientific basis for the transport model, including the qualitative and quantitative data that are of importance for the assessment of uncertainties and confidence in the transport description, and for the understanding of the processes at the sites. Provide transport parameters for use within other discipline-specific programmes. Contribute to the integrated evaluation of the investigated sites. The site descriptive

  15. Insights into organic carbon oxidation potential during fluvial transport from controlled laboratory and natural field experiments

    Science.gov (United States)

    Scheingross, Joel S.; Dellinger, Mathieu; Golombek, Nina; Hilton, Robert G.; Hovius, Niels; Sachse, Dirk; Turowski, Jens M.; Vieth-Hillebrand, Andrea; Wittmann, Hella

    2017-04-01

    Over geologic timescales, the exchange of organic carbon (OC) between the atmosphere, biosphere and geosphere is thought to be a major control on atmospheric carbon dioxide (CO2) concentrations, and hence global climate. The carbon fluxes from the oxidation of rock-derived OC (a CO2 source) and erosion and transport of biospheric OC (a potential CO2 sink) during fluvial transit are approximately the same order of magnitude or larger than those from silicate weathering (France-Lanord and Derry, 1997; Bouchez et al., 2010). Despite field data showing oxidation of OC moving downstream in lowland rivers, it is unclear if losses occur primarily during active fluvial transport within the river, where OC is in continual motion within an aerated environment, or during longer periods when OC is temporarily stored in river floodplains which may be anoxic. This represents a major knowledge gap, as the unknown location of OC oxidation (i.e., river vs. floodplain) limits our ability to develop process-based models that can be employed to predict OC losses, constrain carbon budgets, and unravel links between climate, tectonics, and erosion. To fill this gap, we investigated the potential for OC oxidation in both controlled laboratory experiments and a simplified field setting. We consider both rock-derived and biospheric OC. Our experiments simulated fluvial transport without floodplain storage, allowing mixtures of OC-rich and siliciclastic sediment to be transported for distances of 1000 km in annular flumes while making time-series measurements of OC concentration in both the solid (POC) and dissolved (DOC) loads, as well as measurements of rhenium concentration, which serves as a proxy for the oxidation of rock-derived OC. These transport experiments were compared to static, control experiments where water and sediment in the same proportion were placed in still water. Initial results for transport of OC-rich soil show similar behavior between the transport and static

  16. OPTIMIZATION PROBLEMS ON SUBURBAN TRANSPORT SYSTEMS

    Directory of Open Access Journals (Sweden)

    T. M. Grigorovа

    2015-01-01

    Full Text Available The paper considers problems that permit to solve such issue as organization of  transport service for suburban population with due account of passenger transport fatigue which is considered as one of subconscious criteria for selection of a travel mode. Improvement of transportation process entails an increase in demand for such service. Demands predetermine transport supply and situation on the market depends on supply-and-demand balance.  The paper presents an analysis of approaches to the estimation of  parameters for a suburban transport system with due regard for influence of transport process parameters on the rate of passenger transport fatigue.  This rate is estimated through value of an index which demonstrates an activity of passenger’s regulatory systems while performing every element of motion process. Nonlinear regression equation has been used to describe changes in the activity index of the passenger’s regulatory systems when a passenger is taking a standing position in a passenger compartment of a suburban transport facility. In this case value of activity index of regulatory systems  before transportation, passenger age, transportation duration,   operation factor of transport  capacity and ratio of new bus cost to nominal capacity have been taken as variables for calculations.The paper proposes an index change model for assessment of passenger’s transport fatigue when a passenger has a standing position in a transport facility. The model has shown that an impact of the activity index of passenger’s regulatory systems before  making any elemental motion is rather pertinent because this index provides information on an initial condition of a person before executing any other elemental motion. The influence of the activity index of passenger’s regulatory systems before  making any elemental motion is considered as an important characteristic because it has an impact on passenger’s condition after executing

  17. Dispersive transport across interfaces

    Science.gov (United States)

    Berkowitz, Brian; Adler, Pierre

    2015-04-01

    Experiments demonstrating asymmetrical dispersive transport of a conservative tracer across interfaces between different porous materials have recently been performed. Here, this phenomenon is studied numerically on the pore scale. The flow field is derived by solving the Stokes equation. The dispersive transport is simulated by a large number of particles undergoing random walks under the simultaneous action of convection and diffusion. Two main two-dimensional configurations are studied; each consists of two segments (called coarse and fine) with the same structure, porosity, and length along the main flow, but different characteristic solid/pore sizes. One structure consists of two channels containing cavities of different sizes, and the second of square "grains" of different sizes. At time t=0, a large number of particles is injected (as a pulse) around a given cross-section. The corresponding breakthrough curves (BTCs) are registered as functions of time at six different cross sections. Calculations are made twice; in the first case (CtoF), particles are injected in the coarse side and are transported towards the fine one; in the second one (FtoC), the opposite case is studied. These calculations are performed for various Péclet numbers (Pe). Comparison of the resulting BTCs shows features that are similar to experimental observations, but with qualitative and quantitative differences. The influences of the medium, of the injection and observation planes, and of Pe are detailed and discussed. A BTC for pulse injection can be characterized by its maximum M(t_M) and the time tM at which it occurs. The observed differences for channels bounded by cavities are very small. However for the granular structures, M(t_M) is always larger for FtoC than for CtoF ; tM depends on all the parameters, namely Pe, the size ratio between the large and small grains, the injection and the observation planes. The numerical results are systematically compared with solutions of one

  18. Electronic transport in unconventional superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Graf, M.J.

    1998-12-31

    The author investigates the electron transport coefficients in unconventional superconductors at low temperatures, where charge and heat transport are dominated by electron scattering from random lattice defects. He discusses the features of the pairing symmetry, Fermi surface, and excitation spectrum which are reflected in the low temperature heat transport. For temperatures {kappa}{sub B}T {approx_lt} {gamma} {much_lt} {Delta}{sub 0}, where {gamma} is the bandwidth of impurity induced Andreev states, certain eigenvalues become universal, i.e., independent of the impurity concentration and phase shift. Deep in the superconducting phase ({kappa}{sub B}T {approx_lt} {gamma}) the Wiedemann-Franz law, with Sommerfeld`s value of the Lorenz number, is recovered. He compares the results for theoretical models of unconventional superconductivity in high-{Tc} and heavy fermion superconductors with experiment. The findings show that impurities are a sensitive probe of the low-energy excitation spectrum, and that the zero-temperature limit of the transport coefficients provides an important test of the order parameter symmetry.

  19. Water-transporting proteins.

    Science.gov (United States)

    Zeuthen, Thomas

    2010-04-01

    Transport through lipids and aquaporins is osmotic and entirely driven by the difference in osmotic pressure. Water transport in cotransporters and uniporters is different: Water can be cotransported, energized by coupling to the substrate flux by a mechanism closely associated with protein. In the K(+)/Cl(-) and the Na(+)/K(+)/2Cl(-) cotransporters, water is entirely cotransported, while water transport in glucose uniporters and Na(+)-coupled transporters of nutrients and neurotransmitters takes place by both osmosis and cotransport. The molecular mechanism behind cotransport of water is not clear. It is associated with the substrate movements in aqueous pathways within the protein; a conventional unstirred layer mechanism can be ruled out, due to high rates of diffusion in the cytoplasm. The physiological roles of the various modes of water transport are reviewed in relation to epithelial transport. Epithelial water transport is energized by the movements of ions, but how the coupling takes place is uncertain. All epithelia can transport water uphill against an osmotic gradient, which is hard to explain by simple osmosis. Furthermore, genetic removal of aquaporins has not given support to osmosis as the exclusive mode of transport. Water cotransport can explain the coupling between ion and water transport, a major fraction of transepithelial water transport and uphill water transport. Aquaporins enhance water transport by utilizing osmotic gradients and cause the osmolarity of the transportate to approach isotonicity.

  20. Evaporative loss of cryogenic liquids during vibration and transport in vessels and cisterns

    Science.gov (United States)

    Kaganer, M. G.; Zhukova, R. I.; Nemchinov, A. K.

    1986-04-01

    It is shown that the cause of increased evaporative loss of cryogenic liquids during transportation is scattering of oscillation energy within the liquid. The dependence of the increase in loss on oscillation parameters and transportation conditions is determined.

  1. Transportation Technology: Rail Transport and Logistics

    Science.gov (United States)

    Lang, Aaron B.

    2011-01-01

    Transportation can simply be defined as the movement of goods, services, and people from one location to another. Without an efficient means to transport goods from place to place, the economy would be nothing like it is today. Throughout the history of the United States, American railroads have paved the way toward creating a nation of great…

  2. Intermittent transport in edge plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, O.E.; Naulin, V.; Nielsen, A.H.; Juul Rasmussen, J. [Association EURATOM-Riso National Laboratory, Optics and Plasma Research, Roskilde (Denmark)

    2004-07-01

    The properties of low-frequency convective fluctuations and transport are investigated for the boundary region of magnetized plasmas. We employ a two-dimensional fluid model for the evolution of the global plasma quantities in a geometry and with parameters relevant to the scrape-off layer of confined toroidal plasmas. Strongly intermittent plasma transport is regulated by self-consistently generated sheared poloidal flows and is mediated by burst ejection of particles and heat from the bulk plasma in the form of blobs. Coarse grained probe signals reveal a highly skewed and flat distribution on short time scales, but tends towards a normal distribution at large time scales. Conditionally averaged signals are in perfect agreement with experimental measurements. (authors)

  3. Infrared Drying Parameter Optimization

    Science.gov (United States)

    Jackson, Matthew R.

    In recent years, much research has been done to explore direct printing methods, such as screen and inkjet printing, as alternatives to the traditional lithographic process. The primary motivation is reduction of the material costs associated with producing common electronic devices. Much of this research has focused on developing inkjet or screen paste formulations that can be printed on a variety of substrates, and which have similar conductivity performance to the materials currently used in the manufacturing of circuit boards and other electronic devices. Very little research has been done to develop a process that would use direct printing methods to manufacture electronic devices in high volumes. This study focuses on developing and optimizing a drying process for conductive copper ink in a high volume manufacturing setting. Using an infrared (IR) dryer, it was determined that conductive copper prints could be dried in seconds or minutes as opposed to tens of minutes or hours that it would take with other drying devices, such as a vacuum oven. In addition, this study also identifies significant parameters that can affect the conductivity of IR dried prints. Using designed experiments and statistical analysis; the dryer parameters were optimized to produce the best conductivity performance for a specific ink formulation and substrate combination. It was determined that for an ethylene glycol, butanol, 1-methoxy 2- propanol ink formulation printed on Kapton, the optimal drying parameters consisted of a dryer height of 4 inches, a temperature setting between 190 - 200°C, and a dry time of 50-65 seconds depending on the printed film thickness as determined by the number of print passes. It is important to note that these parameters are optimized specifically for the ink formulation and substrate used in this study. There is still much research that needs to be done into optimizing the IR dryer for different ink substrate combinations, as well as developing a

  4. Measuring the chargino parameters

    Indian Academy of Sciences (India)

    J Kalinowski

    2000-07-01

    After the supersymmetric particles have been discovered, the priority will be to determine independently the fundamental parameters to reveal the structure of the underlying supersymmetric theory. In my talk I discuss how the chargino sector can be reconstructed completely by measuring the cross-sections with polarized beams at e+e- collider experiments: $\\tilde{X}^{+}_{i}\\tilde{X}^{-}_{j}[i,j=1,2]$. The closure of the two-chargino system can be investigated by analysing sum rules for the production cross-sections.

  5. Effects of repeated transport on Holstein calf post-transport behavior and feed intake.

    Science.gov (United States)

    Adams-Progar, A L; Friend, T H; Holub, G A; Krenek, A J; Garey, S M; Terrill, C L

    2015-02-01

    Previous studies have determined that stress causes decreases in feed intake and efficiency in livestock, but the effect of repeated transport on these parameters has not been well studied. This study determined how repeated transport affected calf post-transport behavior, feed intake, ADG, and feed conversion. Thirty-six 4-mo-old Holstein steer calves were housed in groups of 6 with each group randomly assigned to either transport or control treatments. Each calf was assigned to an individual Calan gate feeder and feed intake was recorded daily. Transport calves were transported for 6 h in their groups in a 7.3 by 2.4 m gooseneck trailer divided into 3 compartments, at an average density of 0.87 m/calf, every 7 d for 5 consecutive weeks. After return to their home pens, behavior was recorded for transported calves at 5-min intervals for 1 h. Calf ADG and feed conversion were analyzed in a mixed model ANOVA, whereas feed intake was analyzed as a repeated measure in a mixed model ANOVA. Post-transport, calves followed a pattern of drinking, eating, and then lying down. The highest (82 ± 5% calves) and lowest (0 ± 5% calves) incidences of eating behavior occurred 10 and 60 min post-transport, respectively. Control calves had a higher feed intake than transported calves overall (7.29 ± 0.22 kg for control and 6.91 ± 0.21 kg for transport; = 0.01), for the feeding posttreatment (6.78 ± 0.27 kg for control and 6.01 ± 0.28 kg for transport; = 0.007), and the day after treatment (7.83 ± 0.23 kg for control and 7.08 ± 0.15 kg for transport; = 0.02). Feed intake for the feeding post-transport for transport calves significantly decreased after the second transport but increased with each successive transport ( feed conversion. These results suggest that calves exposed to repeated transport may decrease feed intake compared to nontransported calves as an initial response to transport; however, overall feed conversion was not affected and these Holstein calves may have

  6. Photoinduced diffusion molecular transport

    Science.gov (United States)

    Rozenbaum, Viktor M.; Dekhtyar, Marina L.; Lin, Sheng Hsien; Trakhtenberg, Leonid I.

    2016-08-01

    We consider a Brownian photomotor, namely, the directed motion of a nanoparticle in an asymmetric periodic potential under the action of periodic rectangular resonant laser pulses which cause charge redistribution in the particle. Based on the kinetics for the photoinduced electron redistribution between two or three energy levels of the particle, the time dependence of its potential energy is derived and the average directed velocity is calculated in the high-temperature approximation (when the spatial amplitude of potential energy fluctuations is small relative to the thermal energy). The thus developed theory of photoinduced molecular transport appears applicable not only to conventional dichotomous Brownian motors (with only two possible potential profiles) but also to a much wider variety of molecular nanomachines. The distinction between the realistic time dependence of the potential energy and that for a dichotomous process (a step function) is represented in terms of relaxation times (they can differ on the time intervals of the dichotomous process). As shown, a Brownian photomotor has the maximum average directed velocity at (i) large laser pulse intensities (resulting in short relaxation times on laser-on intervals) and (ii) excited state lifetimes long enough to permit efficient photoexcitation but still much shorter than laser-off intervals. A Brownian photomotor with optimized parameters is exemplified by a cylindrically shaped semiconductor nanocluster which moves directly along a polar substrate due to periodically photoinduced dipole moment (caused by the repetitive excited electron transitions to a non-resonant level of the nanocylinder surface impurity).

  7. DEPOT: A Database of Environmental Parameters, Organizations and Tools

    Energy Technology Data Exchange (ETDEWEB)

    CARSON,SUSAN D.; HUNTER,REGINA LEE; MALCZYNSKI,LEONARD A.; POHL,PHILLIP I.; QUINTANA,ENRICO; SOUZA,CAROLINE A.; HIGLEY,KATHRYN; MURPHIE,WILLIAM

    2000-12-19

    The Database of Environmental Parameters, Organizations, and Tools (DEPOT) has been developed by the Department of Energy (DOE) as a central warehouse for access to data essential for environmental risk assessment analyses. Initial efforts have concentrated on groundwater and vadose zone transport data and bioaccumulation factors. DEPOT seeks to provide a source of referenced data that, wherever possible, includes the level of uncertainty associated with these parameters. Based on the amount of data available for a particular parameter, uncertainty is expressed as a standard deviation or a distribution function. DEPOT also provides DOE site-specific performance assessment data, pathway-specific transport data, and links to environmental regulations, disposal site waste acceptance criteria, other environmental parameter databases, and environmental risk assessment models.

  8. Transport induced inflammatory responses in horses.

    Science.gov (United States)

    Wessely-Szponder, J; Bełkot, Z; Bobowiec, R; Kosior-Korzecka, U; Wójcik, M

    2015-01-01

    Deleterious response to road transport is an important problem in equine practice. It determines different physiological, immunological and metabolic changes which lead to increased susceptibility to several disorders such as pneumonia, diarrhea, colics, laminitis, injuries and rhabdomyolisis. The aim of our study was to look for possible relationships between transportation of female young and older horses over a long and short distance and an inflammatory state reflected by an increase of acute phase protein concentration, oxidative stress and muscle injury. The study was conducted on 24 cold-blooded female horses divided into four groups. Six fillies aged 6-18 months and six mares aged 10-12 years were transported over the distance of about 550 km, six fillies aged 6-18 months and six mares aged 10-12 years were transported over the distance of about 50 km. Plasma and serum were obtained from blood samples taken before transportation (T0), immediately after transportation (T1) and at an abattoir during slaughter (T2). In these samples fibrinogen, MDA, AST and CK were assessed. Fibrinogen increased in all studied groups especially in fillies after long distance transportation, where it reached 205±7.07 mg/dl before transportation, 625±35.35 mg/dl after transportation, and 790±14.14 mg/dl during slaughter. MDA concentrations rose after transportation and reached the maximal level during slaughter. CK activity was more elevated after short transportation in younger horses, whereas initial activity of AST was higher in older horses. We estimated that intensified responses from acute phase, oxidative stress and muscle injury parameters indicated an inflammatory state.

  9. Oxygen transport membrane

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a novel composite oxygen transport membrane as well as its preparation and uses thereof.......The present invention relates to a novel composite oxygen transport membrane as well as its preparation and uses thereof....

  10. Transport research: Quo Vadis?

    CSIR Research Space (South Africa)

    Rust, FC

    2008-07-01

    Full Text Available It is well-recognised internationally that transport and transport infrastructure play a major role both in the stimulation of economic growth, creation of job opportunities and in poverty alleviation. This is of particular importance in South...

  11. Speeding up Transportation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ 2007 was an excellent year for the transportation industry, marked by high speed railway transportation, development of the national expressway network and launch of the Chang'e lunar probe satellite.

  12. FREIGHT TRANSPORT IN EUROPE

    Directory of Open Access Journals (Sweden)

    A. REGGIANI

    2000-01-01

    Full Text Available This paper presents an overview of European policy on the interconnected cross-border transport networks as well as severe problems in estimating empirically the avalanche of goods movements in the European Union (EU. In particular, it deals with the Transalpine freight transport case, which represents one of the most challenging operational and policy issues of the present and future – both international (EU and national (the Alpine countries – freight transport development. The paper is organised to briefly describe the main objectives of EU transport policy, to generally introduce the concept of intermodal transport with particular emphasis on intermodal freight transport and to describe past, present and future development of Trans-Alpine intermodal transport. The scenarios of future development of Trans-Alpine intermodal transport have been particularly analysed.

  13. Transportation Management Workshop: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    This report is a compilation of discussions presented at the Transportation Management Workshop held in Gaithersburg, Maryland. Topics include waste packaging, personnel training, robotics, transportation routing, certification, containers, and waste classification.

  14. Small Satellite Transporter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The primary objective is to determine whether this small satellite transporter is capable of transporting at least four 6U CubeSats is possible for a given set of...

  15. APPLICABILITY OF SEDIMENT TRANSPORT FORMULAS

    Institute of Scientific and Technical Information of China (English)

    Chih Ted YANG; Caian HUANG

    2001-01-01

    The paper provides a comprehensive testing of the applicability of 13 sediment transport formulas under different flow and sediment conditions. The dimensionless parameters used for testing the reliability and sensitivity of formulas are dimensionless particle diameter, relative depth, Froude number, relative shear velocity, dimensionless unit stream power, and sediment concentration. A total of 3,391 sets of laboratory and river data are used in the tests. Engineers may find the test results useful to their selection of formulas under different flow and sediment conditions.

  16. The process of motor transport technology development in intelligent transport systems

    Directory of Open Access Journals (Sweden)

    Rudzinska O.V.

    2016-08-01

    Full Text Available Traffic is now regarded as one of the most complicated components of social and economic development in cities and suburban regions. The most advanced technologies for collecting and processing information about traffic parameters (density, speed, rolling stock should be used in these areas to ensure non-stop traffic flow on the roads. Methodological formation of ITS is based on the systematic approach, which considers the development of ITS services as a system rather than individual modules. Therefore a single open system architecture, protocols, information exchange, form of transport documents, standardization of means of communication parameters used for monitoring and control of vehicles are formed. Some specifications for the list of functions and service groups were made while searching for a solution of transport technology domain problems - commercial vehicles. Typical issues solved in service groups, on organisation of trucking transportations using the intelligent transport systems were defined – interpretation, diagnosis, monitoring, synthesis, forecasting, training and supporting the decisions already taken.

  17. Reverse cholesterol transport revisited

    Institute of Scientific and Technical Information of China (English)

    Astrid; E; van; der; Velde

    2010-01-01

    Reverse cholesterol transport was originally described as the high-density lipoprotein-mediated cholesterol flux from the periphery via the hepatobiliary tract to the intestinal lumen, leading to fecal excretion. Since the introduction of reverse cholesterol transport in the 1970s, this pathway has been intensively investigated. In this topic highlight, the classical reverse cholesterol transport concepts are discussed and the subject reverse cholesterol transport is revisited.

  18. Control of machine functions or transport systems

    Energy Technology Data Exchange (ETDEWEB)

    Woodley, M.D.; Lee, M.J.; Jaeger, J.; King, A.S.

    1983-01-01

    A computer code, COMFORT, has been developed at SLAC for on-line calculation of the strengths of magnetic elements in an electron storage ring or transport beam line, subject to first order fitting constraints on the ring or beam line parameters. This code can also be used off-line as an interactive lattice or beam line design tool.

  19. Transportation in African Development.

    Science.gov (United States)

    Altschul, Robert D.

    1980-01-01

    Examines the structure, role, and needs of Africa's national and intracontinental transportation system. Characteristics of rail, water, road, and air transportation are examined. The conclusion is that high investment in transportation systems is essential to the development process. (Author/KC)

  20. Transport statistics 1995

    CSIR Research Space (South Africa)

    De Haan, ML

    1996-04-01

    Full Text Available This publication contains information on all major modes of transport in South Africa. The transport sector is placed in perspective relative to the macro economy and a number of important transport indicators are given. The document also contains...

  1. Assessing Sensitiveness to Transport

    DEFF Research Database (Denmark)

    Lieb, Christoph; Suter, Stefan; Sánchez, Alfredo

    Summary The EU-project ASSET (ASessing SEnsitiveness to Transport) aims at developing and implementing a concise concept to assess transport sensitive areas (TSA) in a European context, i.e. areas in which transport leads to more serious impacts than in other areas. The aim of work package 2 (WP2...

  2. How stressful is transportation?

    Science.gov (United States)

    It is common for cattle to be transported multiple times during their production life cycle. Transportation events may include calves shipped to backgrounding facilities and feed yards, as well as pregnant cows that may be transported to sale barns or relocated due to drought to access a pasture or ...

  3. One-dimensional spatially dependent solute transport in semi ...

    African Journals Online (AJOL)

    Development of an analytical solutions for groundwater pollution problems are major ... parameters for description of solute transport in porous media. ..... in Department of Mathematics & Astronomy, Lucknow University, Lucknow, India.

  4. Timetable Attractiveness Parameters

    DEFF Research Database (Denmark)

    Schittenhelm, Bernd

    2008-01-01

    Timetable attractiveness is influenced by a set of key parameters that are described in this article. Regarding the superior structure of the timetable, the trend in Europe goes towards periodic regular interval timetables. Regular departures and focus on optimal transfer possibilities make...... these timetables attractive. The travel time in the timetable depends on the characteristics of the infrastructure and rolling stock, the heterogeneity of the planned train traffic and the necessary number of transfers on the passenger’s journey. Planned interdependencies between trains, such as transfers...... and heterogeneous traffic, add complexity to the timetable. The risk of spreading initial delays to other trains and parts of the network increases with the level of timetable complexity....

  5. varying elastic parameters distributions

    KAUST Repository

    Moussawi, Ali

    2014-12-01

    The experimental identication of mechanical properties is crucial in mechanics for understanding material behavior and for the development of numerical models. Classical identi cation procedures employ standard shaped specimens, assume that the mechanical elds in the object are homogeneous, and recover global properties. Thus, multiple tests are required for full characterization of a heterogeneous object, leading to a time consuming and costly process. The development of non-contact, full- eld measurement techniques from which complex kinematic elds can be recorded has opened the door to a new way of thinking. From the identi cation point of view, suitable methods can be used to process these complex kinematic elds in order to recover multiple spatially varying parameters through one test or a few tests. The requirement is the development of identi cation techniques that can process these complex experimental data. This thesis introduces a novel identi cation technique called the constitutive compatibility method. The key idea is to de ne stresses as compatible with the observed kinematic eld through the chosen class of constitutive equation, making possible the uncoupling of the identi cation of stress from the identi cation of the material parameters. This uncoupling leads to parametrized solutions in cases where 5 the solution is non-unique (due to unknown traction boundary conditions) as demonstrated on 2D numerical examples. First the theory is outlined and the method is demonstrated in 2D applications. Second, the method is implemented within a domain decomposition framework in order to reduce the cost for processing very large problems. Finally, it is extended to 3D numerical examples. Promising results are shown for 2D and 3D problems.

  6. Chondrule Transport in Protoplanetary Disks

    CERN Document Server

    Goldberg, Aaron Z; Jacquet, Emmanuel

    2015-01-01

    Chondrule formation remains one of the most elusive early Solar System events. Here, we take the novel approach of employing numerical simulations to investigate chondrule origin beyond purely cosmochemical methods. We model the transport of generically-produced chondrules and dust in a 1D viscous protoplanetary disk model, in order to constrain the chondrule formation events. For a single formation event we are able to match analytical predictions of the memory chondrule and dust populations retain of each other (complementarity), finding that a large mass accretion rate ($\\gtrsim 10^{-7}$~M$_\\odot$~yr$^{-1}$) allows for delays on the order of the disk's viscous timescale between chondrule formation and chondrite accretion. Further, we find older disks to be severely diminished of chondrules, with accretion rates $\\lesssim 10^{-9}$~M$_\\odot$~yr$^{-1}$ for nominal parameters. We then characterize the distribution of chondrule origins in both space and time, as functions of disk parameters and chondrule format...

  7. Inverse Transport Theory of Photoacoustics

    CERN Document Server

    Bal, Guillaume; Jugnon, Vincent

    2009-01-01

    We consider the reconstruction of optical parameters in a domain of interest from photoacoustic data. Photoacoustic tomography (PAT) radiates high frequency electromagnetic waves into the domain and measures acoustic signals emitted by the resulting thermal expansion. Acoustic signals are then used to construct the deposited thermal energy map. The latter depends on the constitutive optical parameters in a nontrivial manner. In this paper, we develop and use an inverse transport theory with internal measurements to extract information on the optical coefficients from knowledge of the deposited thermal energy map. We consider the multi-measurement setting in which many electromagnetic radiation patterns are used to probe the domain of interest. By developing an expansion of the measurement operator into singular components, we show that the spatial variations of the intrinsic attenuation and the scattering coefficients may be reconstructed. We also reconstruct coefficients describing anisotropic scattering of ...

  8. Heat transport in a chaotic magnetic field; Transport de la chaleur dans un champ magnetique chaotique

    Energy Technology Data Exchange (ETDEWEB)

    Feron, Samuel [Service de Physique des Plasmas de Fusion, Dept. de Recherches sur la Fusion Controlee, Association Euratom-CEA, Centre d`Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France)

    1997-09-25

    Heat transport in a plasma with a magnetic perturbation of amplitude b and a transverse diffusion of typical scale {delta} is investigated. On Tore Supra, such a perturbation is induced at the edge by the Ergodic Divertor. Classically, the heat transport is expected to be diffusive, but the experimental evidence does not support such a model. The main experimental features are temperature modulations and a transport barrier which allows no loss of confinement in the core plasma. An analysis of both temperature field and magnetic perturbation indicates clearly delimited regions of strong and weak transport that are related to the loss of memory on a field line due to the transverse diffusion. Furthermore, the perturbation is strongly space-dependent. This implies non-local transport and a region (separatrix) in which the Chirikov parameter is less than one. This analysis leads to a 1D analytical model which recovers modulations. A transport barrier is also expected, assuming a dissymmetrical transport process around the separatrix. A mapping transport code has also been developed which takes the basic features of ergodic divertor into account. Both experimental results, modulations, and a transport barrier are recovered. The latter depends on the ratio b/{delta}, but occurs without any assumption of dissymmetrical transport. For the same ratio b/{delta} as Tore Supra, the core confinement, as with the experiment, is not affected. A lower ratio leads to a loss of confinement, while a larger value produces improved confinement. The barrier can be attributed to non diffusive transport out of islands located around separatrix. The trapping mechanisms in these islands, combined with some small level of transverse transport, reduce the probability for particles to flow back to the perturbed region. A dissymmetrical process then appears and allows for a transport barrier. (author) 90 refs., 65 figs.

  9. Heat transport in a chaotic magnetic field; Transport de la chaleur dans un champ magnetique chaotique

    Energy Technology Data Exchange (ETDEWEB)

    Feron, S. [Association Euratom-CEA, Centre d`Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee]|[Grenoble-1 Univ., 38 (France)

    1997-12-01

    Heat transport in a plasma with a magnetic perturbation of amplitude b and a transverse diffusion of typical scale {delta} is investigated. On Tore Supra, such a perturbation is induced at the edge by the Ergodic Divertor. Classically, the heat transport is expected to be diffusive, but the experimental evidence does not support such a model. The main experimental features are temperature modulations and a transport barrier which allows no loss of confinement in the core plasma. An analysis of both temperature filed nd magnetic perturbation indicates clearly delimited regions of strong and weak transport that are related to the loss of memory on a filed line due to the transverse diffusion. Furthermore, the perturbation is strongly space-dependent. This implies non local transport and a region (separatrix) in which the Chirikov parameter is less that one. This analysis leads to a 1D analytical model which recovers modulations. A transport barrier is also expected, assuming a dissymmetrical transport process around the separatrix. A mapping transport code has also been developed which takes the basic features of the ergodic divertor into account. Both experimental results, modulations, and a transport barrier are recovered. The latter depends on the ratio b/{delta}, but occurs without any assumption of dissymmetrical transport. For the same ratio b/{delta} as Tore Supra, the core confinement, as with the experiment, is not affected. A lower ratio leads to a loss of confinement, while a larger value produces improved confinement. The barrier can be attributed to non diffusive transport out of islands located around the separatrix. The trapping mechanisms in these islands, combined with some small level of transverse transport, reduce the probability for particles to flow back to the perturbed region. A dissymmetrical process then appears and allows for a transport barrier. (author) 90 refs.

  10. Determination of the atrazine migration parameters in Vertisol

    Science.gov (United States)

    Raymundo-Raymundo, E.; Hernandez-Vargas, J.; Nikol'Skii, Yu. N.; Guber, A. K.; Gavi-Reyes, F.; Prado-Pano, B. L.; Figueroa-Sandoval, B.; Mendosa-Hernandez, J. R.

    2010-05-01

    The parameters of the atrazine migration in columns with undisturbed Vertisol sampled from an irrigated plot in Guanajuato, Mexico were determined. A model of the convection-dispersion transport of the chemical compounds accounting for the decomposition and equilibrium adsorption, which is widely applied for assessing the risk of contamination of natural waters with pesticides, was used. The model parameters were obtained by solving the inverse problem of the transport equation on the basis of laboratory experiments on the transport of the 18O isotope and atrazine in soil columns with an undisturbed structure at three filtration velocities. The model adequately described the experimental data at the individual selection of the parameters for each output curve. Physically unsubstantiated parameters of the atrazine adsorption and degradation were obtained when the parameter of the hydrodynamic dispersion was determined from the data on the 18O migration. The simulation also showed that the use of parameters obtained at water content close to saturation in the calculations for an unsaturated soil resulted in the overestimation of the leaching rate and the maximum concentration of atrazine in the output curve compared to the experimental data.

  11. Mass and charge transport in micro and nanofluidic channels

    DEFF Research Database (Denmark)

    Mortensen, Niels Asger; Olesen, Laurits Højgaard; Okkels, Fridolin

    2007-01-01

    and charge transport coefficients that satisfy Onsager relations. In the limit of nonoverlapping Debye layers the transport coefficients are simply expressed in terms of parameters of the electrolyte as well as the hydraulic radiusR ¼ 2A=P with Aand P being the cross-sectional area and perimeter...

  12. Uncertainty in tsunami sediment transport modeling

    Science.gov (United States)

    Jaffe, Bruce E.; Goto, Kazuhisa; Sugawara, Daisuke; Gelfenbaum, Guy R.; La Selle, SeanPaul M.

    2016-01-01

    Erosion and deposition from tsunamis record information about tsunami hydrodynamics and size that can be interpreted to improve tsunami hazard assessment. We explore sources and methods for quantifying uncertainty in tsunami sediment transport modeling. Uncertainty varies with tsunami, study site, available input data, sediment grain size, and model. Although uncertainty has the potential to be large, published case studies indicate that both forward and inverse tsunami sediment transport models perform well enough to be useful for deciphering tsunami characteristics, including size, from deposits. New techniques for quantifying uncertainty, such as Ensemble Kalman Filtering inversion, and more rigorous reporting of uncertainties will advance the science of tsunami sediment transport modeling. Uncertainty may be decreased with additional laboratory studies that increase our understanding of the semi-empirical parameters and physics of tsunami sediment transport, standardized benchmark tests to assess model performance, and development of hybrid modeling approaches to exploit the strengths of forward and inverse models.

  13. Transportation System Requirements Document

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    This Transportation System Requirements Document (Trans-SRD) describes the functions to be performed by and the technical requirements for the Transportation System to transport spent nuclear fuel (SNF) and high-level radioactive waste (HLW) from Purchaser and Producer sites to a Civilian Radioactive Waste Management System (CRWMS) site, and between CRWMS sites. The purpose of this document is to define the system-level requirements for Transportation consistent with the CRWMS Requirement Document (CRD). These requirements include design and operations requirements to the extent they impact on the development of the physical segments of Transportation. The document also presents an overall description of Transportation, its functions, its segments, and the requirements allocated to the segments and the system-level interfaces with Transportation. The interface identification and description are published in the CRWMS Interface Specification.

  14. Intelligent Freigth Transport Systems

    DEFF Research Database (Denmark)

    Overø, Helene Martine; Larsen, Allan; Røpke, Stefan

    2009-01-01

    The Danish innovation project entitled “Intelligent Freight Transport Systems” aims at developing prototype systems integrating public intelligent transport systems (ITS) with the technology in vehicles and equipment as well as the IT-systems at various transport companies. The objective is to en......The Danish innovation project entitled “Intelligent Freight Transport Systems” aims at developing prototype systems integrating public intelligent transport systems (ITS) with the technology in vehicles and equipment as well as the IT-systems at various transport companies. The objective...... is to enhance the efficiency and lower the environmental impact in freight transport. In this paper, a pilot project involving real-time waste collection at a Danish waste collection company is described, and a solution approach is proposed. The problem corresponds to the dynamic version of the waste collection...... problem which can be formulated as a dynamic version of the vehicle routing problem with time windows (VRPTW)....

  15. [Fructose transporter in yeasts].

    Science.gov (United States)

    Lazar, Zbigniew; Dobrowolski, Adam; Robak, Małgorzata

    2014-01-01

    Study of hexoses transporter started with discovery of galactose permease in Saccharomyces cerevisiae. Glucose, fructose and mannose assimilation is assumed by numerous proteins encoded by different genes. To date over 20 hexoses transporters, belonging to Sugar Porter family and to Major Facilitator Superfamily, were known. Genome sequence analysis of Candida glabrata, Kluyveromyces lactis, Yarrowia lipolytica, S. cerevisaie and Debaryomyces hansenii reveled potential presence of 17-48 sugar porter proteins. Glucose transporters in S. cerevisiae have been already characterized. In this paper, hexoses transporters, responsible for assimilation of fructose by cells, are presented and compared. Fructose specific transporter are described for yeasts: Zygosaccharomyces rouxii, Zygosaccharomyces bailli, K. lactis, Saccharomyces pastorianus, S. cerevisiae winemaking strain and for fungus Botritys cinerea and human (Glut5p). Among six yeasts transporters, five are fructose specific, acting by facilitated diffusion or proton symport. Yeasts monosaccharides transporter studies allow understanding of sugars uptake and metabolism important aspects, even in higher eukaryotes cells.

  16. TRANSPORT/HANDLING REQUESTS

    CERN Multimedia

    Groupe ST/HM

    2002-01-01

    A new EDH document entitled 'Transport/Handling Request' will be in operation as of Monday, 11th February 2002, when the corresponding icon will be accessible from the EDH desktop, together with the application instructions. This EDH form will replace the paper-format transport/handling request form for all activities involving the transport of equipment and materials. However, the paper form will still be used for all vehicle-hire requests. The introduction of the EDH transport/handling request form is accompanied by the establishment of the following time limits for the various services concerned: 24 hours for the removal of office items, 48 hours for the transport of heavy items (of up to 6 metric tons and of standard road width), 5 working days for a crane operation, extra-heavy transport operation or complete removal, 5 working days for all transport operations relating to LHC installation. ST/HM Group, Logistics Section Tel: 72672 - 72202

  17. Transportation safety training

    Energy Technology Data Exchange (ETDEWEB)

    Jones, E.

    1990-01-01

    Over the past 25 years extensive federal legislation involving the handling and transport of hazardous materials/waste has been passed that has resulted in numerous overlapping regulations administered and enforced by different federal agencies. The handling and transport of hazardous materials/waste involves a significant number of workers who are subject to a varying degree of risk should an accident occur during handling or transport. Effective transportation training can help workers address these risks and mitigate them, and at the same time enable ORNL to comply with the federal regulations concerning the transport of hazardous materials/waste. This presentation will outline how the Environmental and Health Protection Division's Technical Resources and Training Section at the Oak Ridge National Laboratory, working with transportation and waste disposal personnel, have developed and implemented a comprehensive transportation safety training program to meet the needs of our workers while satisfying appropriate federal regulations. 8 refs., 3 tabs.

  18. [Acoustical parameters of toys].

    Science.gov (United States)

    Harazin, Barbara

    2010-01-01

    Toys play an important role in the development of the sight and hearing concentration in children. They also support the development of manipulation, gently influence a child and excite its emotional activities. A lot of toys emit various sounds. The aim of the study was to assess sound levels produced by sound-emitting toys used by young children. Acoustical parameters of noise were evaluated for 16 sound-emitting plastic toys in laboratory conditions. The noise level was recorded at four different distances, 10, 20, 25 and 30 cm, from the toy. Measurements of A-weighted sound pressure levels and noise levels in octave band in the frequency range from 31.5 Hz to 16 kHz were performed at each distance. Taking into consideration the highest equivalent A-weighted sound levels produced by tested toys, they can be divided into four groups: below 70 dB (6 toys), from 70 to 74 dB (4 toys), from 75 to 84 dB (3 toys) and from 85 to 94 dB (3 toys). The majority of toys (81%) emitted dominant sound levels in octave band at the frequency range from 2 kHz to 4 kHz. Sound-emitting toys produce the highest acoustic energy at the frequency range of the highest susceptibility of the auditory system. Noise levels produced by some toys can be dangerous to children's hearing.

  19. Stochastic analysis of virus transport in aquifers

    Science.gov (United States)

    Campbell, Rehmann L.L.; Welty, C.; Harvey, R.W.

    1999-01-01

    A large-scale model of virus transport in aquifers is derived using spectral perturbation analysis. The effects of spatial variability in aquifer hydraulic conductivity and virus transport (attachment, detachment, and inactivation) parameters on large-scale virus transport are evaluated. A stochastic mean model of virus transport is developed by linking a simple system of local-scale free-virus transport and attached-virus conservation equations from the current literature with a random-field representation of aquifer and virus transport properties. The resultant mean equations for free and attached viruses are found to differ considerably from the local-scale equations on which they are based and include effects such as a free-virus effective velocity that is a function of aquifer heterogeneity as well as virus transport parameters. Stochastic mean free-virus breakthrough curves are compared with local model output in order to observe the effects of spatial variability on mean one-dimensional virus transport in three-dimensionally heterogeneous porous media. Significant findings from this theoretical analysis include the following: (1) Stochastic model breakthrough occurs earlier than local model breakthrough, and this effect is most pronounced for the least conductive aquifers studied. (2) A high degree of aquifer heterogeneity can lead to virus breakthrough actually preceding that of a conservative tracer. (3) As the mean hydraulic conductivity is increased, the mean model shows less sensitivity to the variance of the natural-logarithm hydraulic conductivity and mean virus diameter. (4) Incorporation of a heterogeneous colloid filtration term results in higher predicted concentrations than a simple first-order adsorption term for a given mean attachment rate. (5) Incorporation of aquifer heterogeneity leads to a greater range of virus diameters for which significant breakthrough occurs. (6) The mean model is more sensitive to the inactivation rate of viruses

  20. Solute transport scales in an unsaturated stony soil

    Science.gov (United States)

    Coppola, Antonio; Comegna, Alessandro; Dragonetti, Giovanna; Dyck, Miles; Basile, Angelo; Lamaddalena, Nicola; Kassab, Mohamed; Comegna, Vincenzo

    2011-06-01

    Solute transport parameters are known to be scale-dependent due mainly to the increasing scale of heterogeneities with transport distance and with the lateral extent of the transport field examined. Based on a transect solute transport experiment, in this paper we studied this scale dependence by distinguishing three different scales with different homogeneity degrees of the porous medium: the observation scale, transport scale and transect scale. The main objective was to extend the approach proposed by van Wesenbeeck and Kachanoski to evaluating the role of textural heterogeneities on the transition from the observation scale to the transport scale. The approach is based on the scale dependence of transport moments estimated from solute concentrations distributions. In our study, these moments were calculated starting from time normalized resident concentrations measured by time domain reflectometry (TDR) probes at three depths in 37 soil sites 1 m apart along a transect during a steady state transport experiment. The Generalized Transfer Function (GTF) was used to describe the evolution of apparent solute spreading along the soil profile at each observation site by analyzing the propagation of the moments of the concentration distributions. Spectral analysis was used to quantify the relationship between the solid phase heterogeneities (namely, texture and stones) and the scale dependence of the solute transport parameters. Coupling the two approaches allowed us to identify two different transport scales (around 4-5 m and 20 m, respectively) mainly induced by the spatial pattern of soil textural properties. The analysis showed that the larger transport scale is mainly determined by the skeleton pattern of variability. Our analysis showed that the organization in hierarchical levels of soil variability may have major effects on the differences between solute transport behavior at transport scale and transect scale, as the transect scale parameters will include

  1. A study of parameter identification

    Science.gov (United States)

    Herget, C. J.; Patterson, R. E., III

    1978-01-01

    A set of definitions for deterministic parameter identification ability were proposed. Deterministic parameter identificability properties are presented based on four system characteristics: direct parameter recoverability, properties of the system transfer function, properties of output distinguishability, and uniqueness properties of a quadratic cost functional. Stochastic parameter identifiability was defined in terms of the existence of an estimation sequence for the unknown parameters which is consistent in probability. Stochastic parameter identifiability properties are presented based on the following characteristics: convergence properties of the maximum likelihood estimate, properties of the joint probability density functions of the observations, and properties of the information matrix.

  2. Transport of radioactive substances; Der Transport radioaktiver Stoffe

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-12-15

    The report on the transport of radioactive substances covers the following topics: facts on radioactive materials transport, safety of the transport of radioactive substances, legal regulations and guidelines: a multiform but consistent system, transport of nuclear fuels, safety during the transport of nuclear fuel, future transport of spent fuel elements and high-level radioactive wastes in Germany.

  3. Modelling Transportation of Efavirenz: Inference on possibility of mixed modes of transportation and kinetic solubility

    Directory of Open Access Journals (Sweden)

    Tafireyi eNemaura

    2015-06-01

    Full Text Available Understanding drug transportation mechanisms in the human body is of paramount importance in modelling Pharmacokinetic-Pharmacodynamic relationships. This work gives a novel general model of efavirenz transportation projections based on concentrations simulated from patients on a dose of 600mg. The work puts forward a proposition that transportation can wholly be modeled by concentration and time in a uniform volumetric space. Furthermore, movement entities are used to inform the state of kinetic solubility of a solution. There is use of Ricker’s model, and forms of the Hill’s equation in modelling transportation. Characterization on the movement rates of solution particle are suggested in relation to advection rate of solution particle. At turning points on the transportation rate of solution particle vs concentration curve, a suggestion of possibly change of dominance in the mode of transportation and saturation is made. There are four movement rates postulated at primary micro-level transportation, that are attributed to convection, diffusion (passive transportation ( EI and energy dependent system transportation ( ED in relation to advection. Furthermore, a new parameter is introduced which is defined as an advection rate constant of solution particle. It is postulated to be dependent on two rate constants of solution particle, that is a convection rate constant of solution particle and a saturable transportation rate constant of solution particle. At secondary micro-level transportation, the results show convection as sum of advection and saturable transportation. The kinetics of dissolution of efavirenz in the solution space is postulated. Relatively, a good level of kinetics of dissolution is projected in the concentration region 0−32.82μg/ml.

  4. YOGA IMPROVES CARDIOVASCULAR PARAMETERS

    Directory of Open Access Journals (Sweden)

    Pramod P. Kadu

    2016-06-01

    Full Text Available ABSTRACT Yoga in ancient technique practices by sage for a desirable and healthy life. Yogic exercise and Pranayam may modulate cardiovascular function. To assess the cardiovascular parameter in control and study group. We selected 90 healthy volunteers between age group 35 – 50 years and divided into two groups. i Study group – 45 ii Control group – 45. Control group was not doing any type of exercise or yoga during 1 yr of period whereas yoga group did yogic exercise for 1 yr under supervision of yoga expert. In both the group heart rate SBP and DBP evaluate at 0, 6 and 12 month period. In control group heart rate, SBP, and DBP showed no significant change at 0, 6, and 12 month reading, whereas study group (yoga 81.96±5.65 showed significant decreased heart rate From 81.96 ±5.65 to 75.60 ± 3.44 at 6 month and 73.75 ± 11.36 at 12 month (p<0.001 SBP decreased from 128 ± 7.66 to 120.97 ± 4.21 at 6 month and 120.48± 3.86 at 12 months (p<0.001. DBP showed significant decreased from 88.44 ± 5.25 to 80.53 ± 3.44 at 6 months and 80.53 ± 2.53 at 12months (p<0.001. Yogic exercise and Pranayam done regularly at long term improve cardiovascular efficiency.

  5. Measurement Error Effects of Beam Parameters Determined by Beam Profiles

    CERN Document Server

    Jang, Ji-Ho; Jeon, Dong-O

    2015-01-01

    A conventional method to determine beam parameters is using the profile measurements and converting them into the values of twiss parameters and beam emittance at a specified position. The beam information can be used to improve transverse beam matching between two different beam lines or accelerating structures. This work is related with the measurement error effects of the beam parameters and the optimal number of profile monitors in a section between MEBT (medium energy beam transport) and QWR (quarter wave resonator) of RAON linear accelerator.

  6. Transport, energy and environment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    Transportation demands a large and increasing share of total energy consumption in Europe. At the same time many European countries are facing difficult decisions in achieving their long term environmental goals. Therefore energy policy, environmental policy and transport policy should be seen and discussed in a common perspective. In particular the relative contribution from the transport sector and the energy sector involves a number of important and difficult issues. The aim of the conference was to bring together economists, scientists, manufactures, energy planners, transport planners, and decision makers in order to discuss the importance of the transport sector in relation to energy demand and long term environmental goals. General conference sessions covered. Trends in Transport Energy Demand and Environmental constraints, Technological Development and New Transport Systems, Lifestyle Changes and the Transport Sector, Megacities: Solutions to the Transport and Air Pollution Problems, Effectiveness of Public Policies, Transport and Energy sector, and Methods, Models and Data. The conference took place at Hotel Marienlyst, Elsinore, Denmark and attracted wide interest. The participants represented 14 different countries covering international organisations, ministries, universities, research centres, consulting firms, industry etc. (EG)

  7. Energy and transport.

    Science.gov (United States)

    Woodcock, James; Banister, David; Edwards, Phil; Prentice, Andrew M; Roberts, Ian

    2007-09-22

    We examine the links between fossil-fuel-based transportation, greenhouse-gas emissions, and health. Transport-related carbon emissions are rising and there is increasing consensus that the growth in motorised land vehicles and aviation is incompatible with averting serious climate change. The energy intensity of land transport correlates with its adverse health effects. Adverse health effects occur through climate change, road-traffic injuries, physical inactivity, urban air pollution, energy-related conflict, and environmental degradation. For the world's poor people, walking is the main mode of transport, but such populations often experience the most from the harms of energy-intensive transport. New energy sources and improvements in vehicle design and in information technology are necessary but not sufficient to reduce transport-related carbon emissions without accompanying behavioural change. By contrast, active transport has the potential to improve health and equity, and reduce emissions. Cities require safe and pleasant environments for active transport with destinations in easy reach and, for longer journeys, public transport that is powered by renewable energy, thus providing high levels of accessibility without car use. Much investment in major road projects does not meet the transport needs of poor people, especially women whose trips are primarily local and off road. Sustainable development is better promoted through improving walking and cycling infrastructures, increasing access to cycles, and investment in transport services for essential needs. Our model of London shows how increased active transport could help achieve substantial reductions in emissions by 2030 while improving population health. There exists the potential for a global contraction and convergence in use of fossil-fuel energy for transport to benefit health and achieve sustainability.

  8. Inverse methods for radiation transport

    Science.gov (United States)

    Bledsoe, Keith C.

    Implicit optimization methods for solving the inverse transport problems of interface location identification, source isotope weight fraction identification, shield material identification, and material mass density identification are explored. Among these optimization methods are the Schwinger inverse method, Levenberg-Marquardt method, and evolutionary algorithms. Inverse problems are studied in one-dimensional spherical and two-dimensional cylindrical geometries. The scalar fluxes of unscattered gamma-ray lines, leakages of neutron-induced gamma-ray lines, and/or neutron multiplication in the system are assumed to be measured. Each optimization method is studied on numerical test problems in which the measured data is simulated using the same deterministic transport code used in the optimization process (assuming perfectly consistent measurements) and using a Monte Carlo code (assuming less-consistent, more realistic measurements). The Schwinger inverse method and Levenberg-Marquardt methods are found to be successful for problems with relatively few (i.e. 4 or fewer) unknown parameters, with the former being the best for unknown isotope problems and the latter being more adept at interface location, unknown material mass density, and mixed parameter problems. A study of a variety of evolutionary algorithms indicates that the differential evolution method is the best for inverse transport problems, and outperforms the Levenberg-Marquardt method on problems with large numbers of unknowns. An algorithm created by combining different variants of the differential evolution method is shown to be highly successful on spherical problems with unscattered gamma-ray lines, while a basic differential evolution approach is more useful for problems with scattering and in cylindrical geometries. A hybrid differential evolution/Levenberg-Marquardt algorithm also was found to show promise for fast and robust solution of inverse problems.

  9. Parameters of care for craniosynostosis

    DEFF Research Database (Denmark)

    McCarthy, Joseph G; Warren, Stephen M; Bernstein, Joseph

    2012-01-01

    A multidisciplinary meeting was held from March 4 to 6, 2010, in Atlanta, Georgia, entitled "Craniosynostosis: Developing Parameters for Diagnosis, Treatment, and Management." The goal of this meeting was to create parameters of care for individuals with craniosynostosis....

  10. Transportation economics and energy

    Science.gov (United States)

    Soltani Sobh, Ali

    The overall objective of this research is to study the impacts of technology improvement including fuel efficiency increment, extending the use of natural gas vehicle and electric vehicles on key parameters of transportation. In the first chapter, a simple economic analysis is used in order to demonstrate the adoption rate of natural gas vehicles as an alternative fuel vehicle. The effect of different factors on adoption rate of commuters is calculated in sensitivity analysis. In second chapter the VMT is modeled and forecasted under influence of CNG vehicles in different scenarios. The VMT modeling is based on the time series data for Washington State. In order to investigate the effect of population growth on VMT, the per capita model is also developed. In third chapter the effect of fuel efficiency improvement on fuel tax revenue and greenhouse emission is examined. The model is developed based on time series data of Washington State. The rebound effect resulted from fuel efficiency improvement is estimated and is considered in fuel consumption forecasting. The reduction in fuel tax revenue and greenhouse gas (GHG) emissions as two outcomes of lower fuel consumption are computed. In addition, the proper fuel tax rate to restitute the revenue is suggested. In the fourth chapter effective factors on electric vehicles (EV) adoption is discussed. The constructed model is aggregated binomial logit share model that estimates the modal split between EV and conventional vehicles for different states over time. Various factors are incorporated in the utility function as explanatory variables in order to quantify their effect on EV adoption choices. The explanatory variables include income, VMT, electricity price, gasoline price, urban area and number of EV stations.

  11. S-parameter uncertainty computations

    DEFF Research Database (Denmark)

    Vidkjær, Jens

    1993-01-01

    A method for computing uncertainties of measured s-parameters is presented. Unlike the specification software provided with network analyzers, the new method is capable of calculating the uncertainties of arbitrary s-parameter sets and instrument settings.......A method for computing uncertainties of measured s-parameters is presented. Unlike the specification software provided with network analyzers, the new method is capable of calculating the uncertainties of arbitrary s-parameter sets and instrument settings....

  12. EBS Radionuclide Transport Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    J. Prouty

    2006-07-14

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport

  13. Subsurface Geotechnical Parameters Report

    Energy Technology Data Exchange (ETDEWEB)

    D. Rigby; M. Mrugala; G. Shideler; T. Davidsavor; J. Leem; D. Buesch; Y. Sun; D. Potyondy; M. Christianson

    2003-12-17

    The Yucca Mountain Project is entering a the license application (LA) stage in its mission to develop the nation's first underground nuclear waste repository. After a number of years of gathering data related to site characterization, including activities ranging from laboratory and site investigations, to numerical modeling of processes associated with conditions to be encountered in the future repository, the Project is realigning its activities towards the License Application preparation. At the current stage, the major efforts are directed at translating the results of scientific investigations into sets of data needed to support the design, and to fulfill the licensing requirements and the repository design activities. This document addresses the program need to address specific technical questions so that an assessment can be made about the suitability and adequacy of data to license and construct a repository at the Yucca Mountain Site. In July 2002, the U.S. Nuclear Regulatory Commission (NRC) published an Integrated Issue Resolution Status Report (NRC 2002). Included in this report were the Repository Design and Thermal-Mechanical Effects (RDTME) Key Technical Issues (KTI). Geotechnical agreements were formulated to resolve a number of KTI subissues, in particular, RDTME KTIs 3.04, 3.05, 3.07, and 3.19 relate to the physical, thermal and mechanical properties of the host rock (NRC 2002, pp. 2.1.1-28, 2.1.7-10 to 2.1.7-21, A-17, A-18, and A-20). The purpose of the Subsurface Geotechnical Parameters Report is to present an accounting of current geotechnical information that will help resolve KTI subissues and some other project needs. The report analyzes and summarizes available qualified geotechnical data. It evaluates the sufficiency and quality of existing data to support engineering design and performance assessment. In addition, the corroborative data obtained from tests performed by a number of research organizations is presented to reinforce

  14. Uncertain multi-objective multi-product solid transportation problems

    Indian Academy of Sciences (India)

    DEEPIKA RANI; T R GULATI

    2016-05-01

    The solid transportation problem is an important generalization of the classical transportation problem as it also considers the conveyance constraints along with the source and destination constraints. The problem can be made more effective by incorporating some other factors, which make it useful in real lifesituations. In this paper, we consider a fully fuzzy multi-objective multi-item solid transportation problem and present a method to find its fuzzy optimal-compromise solution using the fuzzy programming technique. To take into account the imprecision in finding the exact values of parameters, all the parameters are taken as trapezoidal fuzzy numbers. A numerical example is solved to illustrate the methodology

  15. Self-similarity and transport in the standard map

    Energy Technology Data Exchange (ETDEWEB)

    Benkadda, S.; Kassibrakis, S.; White, R.B. [Princeton Univ., NJ (United States). Princeton Plasma Physics Lab.; Zaslavsky, G.M. [New York Univ., NY (United States)

    1996-11-01

    Anomalous transport is investigated for the Standard Map. A chain of exact self similar islands in the vicinity of the period 5 accelerator island is found for a particular value of the map parameter. The transport is found to be superdiffusive with an anomalous exponent related to the characteristic temporal and spatial scaling parameters of the island chain. The value of the transport exponent is compared to the theory. The escape time distribution and Poincare recurrence distribution are found to have power-like tails and the corresponding exponents are obtained and compared to the theory.

  16. Liver iron transport

    Institute of Scientific and Technical Information of China (English)

    Ross M Graham; Anita CG Chua; Carly E Herbison; John K Olynyk; Debbie Trinder

    2007-01-01

    The liver plays a central role in iron metabolism. It is the major storage site for iron and also expresses a complex range of molecules which are involved in iron transport and regulation of iron homeostasis. An increasing number of genes associated with hepatic iron transport or regulation have been identified. These include transferrin receptors (TFR1 and 2), a ferrireductase (STEAP3), the transporters divalent metal transporter-1 (DMT1) and ferroportin (FPN) as well as the haemochromatosis protein, HFE and haemojuvelin (HJV),which are signalling molecules. Many of these genes also participate in iron regulatory pathways which focus on the hepatic peptide hepcidin. However, we are still only beginning to understand the complex interactions between liver iron transport and iron homeostasis. This review outlines our current knowledge of molecules of iron metabolism and their roles in iron transport and regulation of iron homeostasis.

  17. Transport Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    Transport is the sector with the highest final energy consumption and, without any significant policy changes, is forecast to remain so. In 2008, the IEA published 25 energy efficiency recommendations, among which four are for the transport sector. The recommendations focus on road transport and include policies on improving tyre energy efficiency, fuel economy standards for both light-duty vehicles and heavy-duty vehicles, and eco-driving. Implementation of the recommendations has been weaker in the transport sector than others. This paper updates the progress that has been made in implementing the transport energy efficiency recommendations in IEA countries since March 2009. Many countries have in the last year moved from 'planning to implement' to 'implementation underway', but none have fully implemented all transport energy efficiency recommendations. The IEA calls therefore for full and immediate implementation of the recommendations.

  18. Radionuclide Transport Models Under Ambient Conditions

    Energy Technology Data Exchange (ETDEWEB)

    G. Moridis; Q. Hu

    2000-03-12

    The purpose of this Analysis/Model Report (AMR) is to evaluate (by means of 2-D semianalytical and 3-D numerical models) the transport of radioactive solutes and colloids in the unsaturated zone (UZ) under ambient conditions from the potential repository horizon to the water table at Yucca Mountain (YM), Nevada. This is in accordance with the ''AMR Development Plan U0060, Radionuclide Transport Models Under Ambient Conditions'' (CRWMS M and O 1999a). This AMR supports the UZ Flow and Transport Process Model Report (PMR). This AMR documents the UZ Radionuclide Transport Model (RTM). This model considers: the transport of radionuclides through fractured tuffs; the effects of changes in the intensity and configuration of fracturing from hydrogeologic unit to unit; colloid transport; physical and retardation processes and the effects of perched water. In this AMR they document the capabilities of the UZ RTM, which can describe flow (saturated and/or unsaturated) and transport, and accounts for (a) advection, (b) molecular diffusion, (c) hydrodynamic dispersion (with full 3-D tensorial representation), (d) kinetic or equilibrium physical and/or chemical sorption (linear, Langmuir, Freundlich or combined), (e) first-order linear chemical reaction, (f) radioactive decay and tracking of daughters, (g) colloid filtration (equilibrium, kinetic or combined), and (h) colloid-assisted solute transport. Simulations of transport of radioactive solutes and colloids (incorporating the processes described above) from the repository horizon to the water table are performed to support model development and support studies for Performance Assessment (PA). The input files for these simulations include transport parameters obtained from other AMRs (i.e., CRWMS M and O 1999d, e, f, g, h; 2000a, b, c, d). When not available, the parameter values used are obtained from the literature. The results of the simulations are used to evaluate the transport of radioactive

  19. EUROPEAN MARITIME TRANSPORT POLICY

    Directory of Open Access Journals (Sweden)

    Jerzy Kujawa

    2014-03-01

    Full Text Available The article describes the common EU policy on maritime transport, which comprises almost 80% of the volume of external trade of the Union and about 40% of internal transport needs. The first part of the paper presents the origins of the common maritime transport policy and the difficulties encountered during its initial formation. Subsequently, the evolution of the concepts of the policy and its current shape is discussed. The final, substantial part of the article describes the main aims and directions of the EU maritime transport policy and includes an evaluation of the effects of the policy.

  20. WASTE PACKAGE TRANSPORTER DESIGN

    Energy Technology Data Exchange (ETDEWEB)

    D.C. Weddle; R. Novotny; J. Cron

    1998-09-23

    The purpose of this Design Analysis is to develop preliminary design of the waste package transporter used for waste package (WP) transport and related functions in the subsurface repository. This analysis refines the conceptual design that was started in Phase I of the Viability Assessment. This analysis supports the development of a reliable emplacement concept and a retrieval concept for license application design. The scope of this analysis includes the following activities: (1) Assess features of the transporter design and evaluate alternative design solutions for mechanical components. (2) Develop mechanical equipment details for the transporter. (3) Prepare a preliminary structural evaluation for the transporter. (4) Identify and recommend the equipment design for waste package transport and related functions. (5) Investigate transport equipment interface tolerances. This analysis supports the development of the waste package transporter for the transport, emplacement, and retrieval of packaged radioactive waste forms in the subsurface repository. Once the waste containers are closed and accepted, the packaged radioactive waste forms are termed waste packages (WP). This terminology was finalized as this analysis neared completion; therefore, the term disposal container is used in several references (i.e., the System Description Document (SDD)) (Ref. 5.6). In this analysis and the applicable reference documents, the term ''disposal container'' is synonymous with ''waste package''.

  1. RELATIVISTIC TRANSPORT-THEORY

    NARCIS (Netherlands)

    MALFLIET, R

    1993-01-01

    We discuss the present status of relativistic transport theory. Special emphasis is put on problems of topical interest: hadronic features, thermodynamical consistent approximations and spectral properties.

  2. Thermodynamics of ABC transporters.

    Science.gov (United States)

    Zhang, Xuejun C; Han, Lei; Zhao, Yan

    2016-01-01

    ABC transporters form the largest of all transporter families, and their structural study has made tremendous progress over recent years. However, despite such advances, the precise mechanisms that determine the energy-coupling between ATP hydrolysis and the conformational changes following substrate binding remain to be elucidated. Here, we present our thermodynamic analysis for both ABC importers and exporters, and introduce the two new concepts of differential-binding energy and elastic conformational energy into the discussion. We hope that the structural analysis of ABC transporters will henceforth take thermodynamic aspects of transport mechanisms into account as well.

  3. Moisture Transport in Wood

    DEFF Research Database (Denmark)

    Astrup, T.; Hansen, K. K.; Hoffmeyer, P.

    2005-01-01

    Modelling of moisture transport in wood is of great importance as most mechanical and physical properties of wood depend on moisture content. Moisture transport in porous materials is often described by Ficks second law, but several observations indicate that this does not apply very well to wood....... Recently at the Technical University of Denmark, Department of Civil Engineering, a new model for moisture transport in wood has been developed. The model divides the transport into two phases, namely water vapour in the cell lumens and bound water in the cell walls....

  4. Transportation Outreach Program Plan

    Energy Technology Data Exchange (ETDEWEB)

    1991-08-01

    The Department of Energy (DOE) Transportation Management Program (TMP) is committed to providing opportunities for public interaction, working cooperatively with groups interested in or affected by DOE transportation, and providing information through the development and implementation of its Outreach Program. This Plan describes how the DOE plans to involve the public in its transportation programs. This Transportation Outreach Program Plan will assist the Secretary of Energy is carrying out his vision of the good neighbor'' policy. The Department of Energy encourages face to face interaction and welcomes comments from everyone. Outreach means to go beyond,'' and the TMP, through its Outreach Program, will hear and address the public's concerns and recommendations about transportation of hazardous and radioactive materials. The TMP Outreach Program is based on a commitment to two-way communication. The TMP coordinates transportation policy for all DOE programs to ensure consistent approaches issues and operations. The TMP conducts outreach by interacting with many groups interested in DOE transportation, facilitating resolution of issues and information exchange, and coordinating the DOE's transportation emergency preparedness capabilities. Many of the specific activities in transportation outreach are usually carried out by field and area offices. 4 figs., 2 tabs.

  5. Moisture Transport in Wood

    DEFF Research Database (Denmark)

    Astrup, T.; Hansen, K. K.; Hoffmeyer, P.;

    2005-01-01

    Modelling of moisture transport in wood is of great importance as most mechanical and physical properties of wood depend on moisture content. Moisture transport in porous materials is often described by Ficks second law, but several observations indicate that this does not apply very well to wood....... Recently at the Technical University of Denmark, Department of Civil Engineering, a new model for moisture transport in wood has been developed. The model divides the transport into two phases, namely water vapour in the cell lumens and bound water in the cell walls....

  6. Hopping transport in solids

    CERN Document Server

    Pollak, M

    1991-01-01

    The hopping process, which differs substantially from conventional transport processes in crystals, is the central process in the transport phenomena discussed in this book. Throughout the book the term ``hopping'' is defined as the inelastic tunneling transfer of an electron between two localized electronic states centered at different locations. Such processes do not occur in conventional electronic transport in solids, since localized states are not compatible with the translational symmetry of crystals.The rapid growth of interest in hopping transport has followed in the footsteps of the

  7. Uncertainty calculation in transport models and forecasts

    DEFF Research Database (Denmark)

    Manzo, Stefano; Prato, Carlo Giacomo

    in a four-stage transport model related to different variable distributions (to be used in a Monte Carlo simulation procedure), assignment procedures and levels of congestion, at both the link and the network level. The analysis used as case study the Næstved model, referring to the Danish town of Næstved2...... the uncertainty propagation pattern over time specific for key model outputs becomes strategically important. 1 Manzo, S., Nielsen, O. A. & Prato, C. G. (2014). The Effects of uncertainty in speed-flow curve parameters on a large-scale model. Transportation Research Record, 1, 30-37. 2 Manzo, S., Nielsen, O. A...

  8. Red cell properties after different modes of blood transportation

    Directory of Open Access Journals (Sweden)

    Asya Makhro

    2016-07-01

    Full Text Available Transportation of blood samples is unavoidable for assessment of specific parameters in blood of patients with rare anemias, blood doping testing or for research purposes. Despite the awareness that shipment may substantially alter multiple parameters, no study of that extend has been performed to assess these changes and optimize shipment conditions to reduce transportation-related artifacts. Here we investigate the changes in multiple parameters in blood of healthy donors over 72 hours of simulated shipment conditions. Three different anticoagulants (K3EDTA, Sodium Heparin and citrate-based CPDA for two temperatures (4oC and room temperature were tested to define the optimal transportation conditions. Parameters measured cover common cytology and biochemistry parameters (complete blood count, hematocrit, morphological examination, red blood cell (RBC volume, ion content and density, membrane properties and stability (hemolysis, osmotic fragility, membrane heat stability, patch-clamp investigations and formation of micro vesicles, Ca2+ handling, RBC metabolism, activity of numerous enzymes and O2 transport capacity. Our findings indicate that individual sets of parameter may require different shipment settings (anticoagulants, temperature. Most of the parameters except for ion (Na+, K+, Ca2+ handling and, possibly, reticulocytes counts, tend to favor transportation at 4oC. Whereas plasma and intraerythrocytic Ca2+ cannot be accurately measured in the presence of chelators such as citrate and EDTA, majority of Ca2+-dependent parameters are stabilized in CPDA samples. Even in blood samples from healthy donors transported using optimized shipment protocol the majority of parameters were stable within 24 hours, the condition that may not hold for the samples of patients with rare anemias. This implies for the as short as possible shipping using fast courier services to the closest expert laboratory at reach. Mobile laboratories or the travel of the

  9. Self-adjoint integral operator for bounded nonlocal transport

    Science.gov (United States)

    Maggs, J. E.; Morales, G. J.

    2016-11-01

    An integral operator is developed to describe nonlocal transport in a one-dimensional system bounded on both ends by material walls. The "jump" distributions associated with nonlocal transport are taken to be Lévy α -stable distributions, which become naturally truncated by the bounding walls. The truncation process results in the operator containing a self-consistent, convective inward transport term (pinch). The properties of the integral operator as functions of the Lévy distribution parameter set [α ,γ ] and the wall conductivity are presented. The integral operator continuously recovers the features of local transport when α =2 . The self-adjoint formulation allows for an accurate description of spatial variation in the Lévy parameters in the nonlocal system. Spatial variation in the Lévy parameters is shown to result in internally generated flows. Examples of cold-pulse propagation in nonlocal systems illustrate the capabilities of the methodology.

  10. SITE-SCALE SATURATED ZONE TRANSPORT

    Energy Technology Data Exchange (ETDEWEB)

    S. KELLER

    2004-11-03

    This work provides a site-scale transport model for calculating radionuclide transport in the saturated zone (SZ) at Yucca Mountain, for use in the abstractions model in support of ''Total System Performance Assessment for License Application'' (TSPA-LA). The purpose of this model report is to provide documentation for the components of the site-scale SZ transport model in accordance with administrative procedure AP-SIII.10Q, Models. The initial documentation of this model report was conducted under the ''Technical Work Plan For: Saturated Zone Flow and Transport Modeling and Testing'' (BSC 2003 [DIRS 163965]). The model report has been revised in accordance with the ''Technical Work Plan For: Natural System--Saturated Zone Analysis and Model Report Integration'', Section 2.1.1.4 (BSC 2004 [DIRS 171421]) to incorporate Regulatory Integration Team comments. All activities listed in the technical work plan that are appropriate to the transport model are documented in this report and are described in Section 2.1.1.4 (BSC 2004 [DIRS 171421]). This report documents: (1) the advection-dispersion transport model including matrix diffusion (Sections 6.3 and 6.4); (2) a description and validation of the transport model (Sections 6.3 and 7); (3) the numerical methods for simulating radionuclide transport (Section 6.4); (4) the parameters (sorption coefficient, Kd ) and their uncertainty distributions used for modeling radionuclide sorption (Appendices A and C); (5) the parameters used for modeling colloid-facilitated radionuclide transport (Table 4-1, Section 6.4.2.6, and Appendix B); and (6) alternative conceptual models and their dispositions (Section 6.6). The intended use of this model is to simulate transport in saturated fractured porous rock (double porosity) and alluvium. The particle-tracking method of simulating radionuclide transport is incorporated in the finite-volume heat and mass transfer numerical

  11. Momentum transport in gyrokinetic turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Buchholz, Rico

    2016-07-01

    In this thesis, the gyrokinetic-Vlasov code GKW is used to study turbulent transport, with a focus on radial transport of toroidal momentum. To support the studies on turbulent transport an eigenvalue solver has been implemented into GKW. This allows to find, not only the most unstable mode, but also subdominant modes. Furthermore it is possible to follow the modes in parameter scans. Furthermore, two fundamental mechanisms that can generate an intrinsic rotation have been investigated: profile shearing and the velocity nonlinearity. The study of toroidal momentum transport in a tokamak due to profile shearing reveals that the momentum flux can not be accurately described by the gradient in the turbulent intensity. Consequently, a description using the profile variation is used. A linear model has been developed that is able to reproduce the variations in the momentum flux as the profiles of density and temperature vary, reasonably well. It uses, not only the gradient length of density and temperature profile, but also their derivative, i.e. the second derivative of the logarithm of the temperature and the density profile. It is shown that both first as well as second derivatives contribute to the generation of a momentum flux. A difference between the linear and nonlinear simulations has been found with respect to the behaviour of the momentum flux. In linear simulations the momentum flux is independent of the normalized Larmor radius ρ{sub *}, whereas it is linear in ρ{sub *} for nonlinear simulations, provided ρ{sub *} is small enough (≤4.10{sup -3}). Nonlinear simulations reveal that the profile shearing can generate an intrinsic rotation comparable to that of current experiments. Under reactor conditions, however, the intrinsic rotation from the profile shearing is expected to be small due to the small normalized Larmor radius ρ{sub *}

  12. Sediment transport capacity of hyperconcentrated flow

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    As one of the most important components of river mechanics,sediment transport capacity of sediment-laden flows has attracted much attention from many researchers working on river mechanics and hydraulic engineering. Based on the time-averaged equation for a turbulent energy equilibrium in solid and liquid two-phase flow,an expression for the efficiency coefficient of suspended load movement was derived for the two-dimensional,steady,uniform,fully-developed turbulent flow. A new structural expression of sediment transport capacity was achieved. Using 115 runs of flume experimental data,which were obtained through two kinds of sediment transport experiments in the state of equilibrium,in combination with the basic rheological and sediment transporting characteristics of hyperconcentrated flow,the main parameters in the structural expression of sediment transport capacity were calibrated,and a new formula of sediment transport capacity for hyperconcentrated flow was developed. A large amount of field data from the Yellow River,Wuding River,and Yangtze River,etc. were adopted to verify the new formula and good agreement was obtained. These results above contribute to an improved theoretical system of river mechanics and a reliable tool for management of rivers carrying high concentration of sediments.

  13. Sediment transport capacity of hyperconcentrated flow

    Institute of Scientific and Technical Information of China (English)

    SHU AnPing; FEI XiangJun

    2008-01-01

    As one of the most important components of river mechanics, sediment transport capacity of sediment-laden flows has attracted much attention from many re-searchers working on river mechanics and hydraulic engineering. Based on the time-averaged equation for a turbulent energy equilibrium in solid and liquid two-phase flow, an expression for the efficiency coefficient of suspended load movement was derived for the two-dimensional, steady, uniform, fully-developed turbulent flow. A new structural expression of sediment transport capacity was achieved. Using 115 runs of flume experimental data, which were obtained through two kinds of sediment transport experiments in the state of equilibrium, in combi-nation with the basic rheological and sediment transporting characteristics of hy-perconcentrated flow, the main parameters in the structural expression of sediment transport capacity were calibrated, and a new formula of sediment transport ca-pacity for hyperconcentrated flow was developed. A large amount of field data from the Yellow River, Wuding River, and Yangtze River, etc. were adopted to verify the new formula and good agreement was obtained. These results above contribute to an improved theoretical system of river mechanics and a reliable tool for man-agement of rivers carrying high concentration of sediments.

  14. Bronchial mucus transport

    NARCIS (Netherlands)

    van der Schans, Cees P.

    2007-01-01

    Effective clearance of inhaled particles requires mucus production and continuous mucus transport from the lower airways to the oropharynx. Mucus production takes place mainly in the peripheral airways. Mucus transport is achieved by the action of the ciliated cells that cover the inner surface of t

  15. Human peptide transporters

    DEFF Research Database (Denmark)

    Nielsen, Carsten Uhd; Brodin, Birger; Jørgensen, Flemming Steen

    2002-01-01

    Peptide transporters are epithelial solute carriers. Their functional role has been characterised in the small intestine and proximal tubules, where they are involved in absorption of dietary peptides and peptide reabsorption, respectively. Currently, two peptide transporters, PepT1 and PepT2, wh...

  16. Conservation in transportation

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-05-30

    A nationwide examination was made of grassroots energy conservation programs related to transportation. Information compiled from civic groups, trade associations, and corporations is included on driver awareness/mass transit; travel; and ride sharing. It is concluded that a willingness by the public to cooperate in transportation energy conservation exists and should be exploited. (LCL)

  17. Transport of sugars.

    Science.gov (United States)

    Chen, Li-Qing; Cheung, Lily S; Feng, Liang; Tanner, Widmar; Frommer, Wolf B

    2015-01-01

    Soluble sugars serve five main purposes in multicellular organisms: as sources of carbon skeletons, osmolytes, signals, and transient energy storage and as transport molecules. Most sugars are derived from photosynthetic organisms, particularly plants. In multicellular organisms, some cells specialize in providing sugars to other cells (e.g., intestinal and liver cells in animals, photosynthetic cells in plants), whereas others depend completely on an external supply (e.g., brain cells, roots and seeds). This cellular exchange of sugars requires transport proteins to mediate uptake or release from cells or subcellular compartments. Thus, not surprisingly, sugar transport is critical for plants, animals, and humans. At present, three classes of eukaryotic sugar transporters have been characterized, namely the glucose transporters (GLUTs), sodium-glucose symporters (SGLTs), and SWEETs. This review presents the history and state of the art of sugar transporter research, covering genetics, biochemistry, and physiology-from their identification and characterization to their structure, function, and physiology. In humans, understanding sugar transport has therapeutic importance (e.g., addressing diabetes or limiting access of cancer cells to sugars), and in plants, these transporters are critical for crop yield and pathogen susceptibility.

  18. Transportation: Topic Paper E.

    Science.gov (United States)

    National Council on the Handicapped, Washington, DC.

    As one of a series of topic papers assessing federal laws and programs affecting persons with disabilities, this paper reviews the issue of transportation services. In the area of urban mass transit, four relevant pieces of legislation and public transportation accessibility regulations are cited, and cost issues are explored. Paratransit systems,…

  19. Passenger transport research

    CSIR Research Space (South Africa)

    Mokonyama, Mathetha T

    2008-03-01

    Full Text Available In South Africa, airport and airline services epitomise what many would like to see in everyday public transport. The CSIR investigates what it will take to provide a commercial public transport service in South Africa which resembles commercial air...

  20. Human peptide transporters

    DEFF Research Database (Denmark)

    Nielsen, Carsten Uhd; Brodin, Birger; Jørgensen, Flemming Steen;

    2002-01-01

    Peptide transporters are epithelial solute carriers. Their functional role has been characterised in the small intestine and proximal tubules, where they are involved in absorption of dietary peptides and peptide reabsorption, respectively. Currently, two peptide transporters, PepT1 and PepT2...

  1. Energy technology for transport

    Energy Technology Data Exchange (ETDEWEB)

    Sloth, M. [H2 Logic (Denmark); Schroeder Pedersen, A. [Risoe National Lab. - DTU (Denmark)

    2007-11-15

    World energy demand for transport has increased significantly for many years. This trend is projected to continue in the years to come, one reason being that large and rapidly developing economies bring increasing demand for the transport of goods and people, including rising transport demand due to greater integration of developing countries in the international trade. Transport not only account for approximately 20 % of the total world energy consumption, but is almost entirely based on limited and expensive fossil energy resources. Technology development and economic incentives are key areas in bringing clean energy to the transportation sector. This chapter recommends that technology development must aim to make each link of the energy conversion chain cheaper, cleaner and more efficient. It should be driven by public-private partnerships, with a funding basis balance that reflects the nearness of each technology to commercial application. Onboard storage, for instance, still needs basic research, whereas fuel cells are already competitive in certain markets. For consumers, fossil fuels are certain to remain the cheapest option for transport as long as energy prices do not reflect the cost of environmental damage. To reduce CO{sub 2} emissions from transport, governments are recommended to set up strong economic or other incentives to encourage consumers to opt for low-carbon vehicles or public transport. As well as reducing environmental damage, such measures could generate money to support research and development in clean energy technologies. (BA)

  2. Sustainable Inland Transportation

    NARCIS (Netherlands)

    Bloemhof, J.M.; Laan, van der E.A.; Beijer, C.

    2011-01-01

    Inland navigation is often mentioned as a ‘green’ alternative for the two other main inland transport modes: rail and road transport. In order to investigate the opportunities for inland navigation we first analyze the competitive position of inland navigation vis-à-vis the other main inland transpo

  3. Sustainable Inland Transportation

    NARCIS (Netherlands)

    Bloemhof, J.M.; Laan, van der E.A.; Beijer, C.

    2011-01-01

    Inland navigation is often mentioned as a ‘green’ alternative for the two other main inland transport modes: rail and road transport. In order to investigate the opportunities for inland navigation we first analyze the competitive position of inland navigation vis-à-vis the other main inland transpo

  4. Scaling and pedotransfer in numerical simulations of flow and transport in soils

    Science.gov (United States)

    Flow and transport parameters of soils in numerical simulations need to be defined at the support scale of computational grid cells. Such support scale can substantially differ from the support scale in laboratory or field measurements of flow and transport parameters. The scale-dependence of flow a...

  5. New prospects of transportation mobility

    OpenAIRE

    Cheng-Min Feng

    2014-01-01

    The demand for improving the quality and efficiency of transportation service has been growing, and new technologies have been entering the market at a rapid pace. Creative thinking and approaches are increasingly important for governments in shaping their transportation policy and actions. This paper aims to discuss several challenges pertaining to the topic, including instant transportation, sharing transportation, fast transportation, resilient transportation, affordable transportation, an...

  6. Transportation Sector Model of the National Energy Modeling System. Volume 2 -- Appendices: Part 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-01-01

    This volume contains input data and parameters used in the model of the transportation sector of the National Energy Modeling System. The list of Transportation Sector Model variables includes parameters for the following: Light duty vehicle modules (fuel economy, regional sales, alternative fuel vehicles); Light duty vehicle stock modules; Light duty vehicle fleet module; Air travel module (demand model and fleet efficiency model); Freight transport module; Miscellaneous energy demand module; and Transportation emissions module. Also included in these appendices are: Light duty vehicle market classes; Maximum light duty vehicle market penetration parameters; Aircraft fleet efficiency model adjustment factors; and List of expected aircraft technology improvements.

  7. Transport, environment and sustainability

    DEFF Research Database (Denmark)

    Joumard, Robert; Gudmundsson, Henrik; Kehagia, Fotini

    2010-01-01

    support tools are discussed. We define what "environmental sustainability in transport" may mean through the transport system, the concepts of sustainable development and of environment. The concept of 'chain of causality' between a source and a final target is developed, as a common reference...... as well as multi-criteria methods. Five case studies are presented. Finally, recommendations for continued research and development of indicators and joint considerations methods for assessment of environmental sustainability in transport are given.......This report is the final report of the action COST 356 'EST - Towards the definition of a measurable environmentally sustainable transport'. It tries to answer the following questions: How can environmental impacts of transport be measured? How can measurements be transformed into operational...

  8. Nonlinear acceleration of SN transport calculations

    Energy Technology Data Exchange (ETDEWEB)

    Fichtl, Erin D [Los Alamos National Laboratory; Warsa, James S [Los Alamos National Laboratory; Calef, Matthew T [Los Alamos National Laboratory

    2010-12-20

    The use of nonlinear iterative methods, Jacobian-Free Newton-Krylov (JFNK) in particular, for solving eigenvalue problems in transport applications has recently become an active subject of research. While JFNK has been shown to be effective for k-eigenvalue problems, there are a number of input parameters that impact computational efficiency, making it difficult to implement efficiently in a production code using a single set of default parameters. We show that different selections for the forcing parameter in particular can lead to large variations in the amount of computational work for a given problem. In contrast, we present a nonlinear subspace method that sits outside and effectively accelerates nonlinear iterations of a given form and requires only a single input parameter, the subspace size. It is shown to consistently and significantly reduce the amount of computational work when applied to fixed-point iteration, and this combination of methods is shown to be more efficient than JFNK for our application.

  9. PARAMETER ESTIMATION OF EXPONENTIAL DISTRIBUTION

    Institute of Scientific and Technical Information of China (English)

    XU Haiyan; FEI Heliang

    2005-01-01

    Because of the importance of grouped data, many scholars have been devoted to the study of this kind of data. But, few documents have been concerned with the threshold parameter. In this paper, we assume that the threshold parameter is smaller than the first observing point. Then, on the basis of the two-parameter exponential distribution, the maximum likelihood estimations of both parameters are given, the sufficient and necessary conditions for their existence and uniqueness are argued, and the asymptotic properties of the estimations are also presented, according to which approximate confidence intervals of the parameters are derived. At the same time, the estimation of the parameters is generalized, and some methods are introduced to get explicit expressions of these generalized estimations. Also, a special case where the first failure time of the units is observed is considered.

  10. MODFLOW-style parameters in underdetermined parameter estimation

    Science.gov (United States)

    D'Oria, Marco D.; Fienen, Michael N.

    2012-01-01

    In this article, we discuss the use of MODFLOW-Style parameters in the numerical codes MODFLOW_2005 and MODFLOW_2005-Adjoint for the definition of variables in the Layer Property Flow package. Parameters are a useful tool to represent aquifer properties in both codes and are the only option available in the adjoint version. Moreover, for overdetermined parameter estimation problems, the parameter approach for model input can make data input easier. We found that if each estimable parameter is defined by one parameter, the codes require a large computational effort and substantial gains in efficiency are achieved by removing logical comparison of character strings that represent the names and types of the parameters. An alternative formulation already available in the current implementation of the code can also alleviate the efficiency degradation due to character comparisons in the special case of distributed parameters defined through multiplication matrices. The authors also hope that lessons learned in analyzing the performance of the MODFLOW family codes will be enlightening to developers of other Fortran implementations of numerical codes.

  11. Logistic innovations in transport

    Directory of Open Access Journals (Sweden)

    Mirosław Antonowicz

    2014-03-01

    Full Text Available Introduction: The article discusses the issue of logistic innovations in transport. The essentials of logistic innovations in transport together with some examples of specific innovations are presented. The role of the client's needs in transport innovations is indicated. The most vital postulates affecting the innovativeness of shipping companies and derived from the author's experience as well as scholarly publications, are time, safety, reliability as well as comprehensiveness of service offer. Following the analysis of the issue, and on the grounds of Kaizen's and Lean's method, the concept of continuous innovations is suggested as very useful for the development of transport. The potential of clusters as the source of logistic innovations in transport is emphasised. Methods: The discussion of the issue was preceded by the author's analysis of written sources on innovativeness, the evaluation of ratings of innovativeness as well as the analysis of rewarded innovative solutions in transport subsequent to the businesses participation in the programme of innovative solutions in transport. The role of innovation practical business operations is argued following the analysis of some strategic documents such as: 2011 White Paper and the Strategy for the Development of Transport by 2020 adopted by the Polish government in 2013. Aim: The aim of the article is to present the role and significance of the issue of logistic innovations in transport and to cite instances of practical solutions implemented by shipping companies, the solutions which resulted in measurable effects. Following the author's observation of the instances of innovative solutions as well as his analysis of the ratings of innovativeness, the article aims to present the conclusions as for the specific kinds of activities which are indispensable to foster innovativeness in transport. Conclusions: The conclusions derived from the author's analyses and observations show that logistic

  12. Parameter estimation in food science.

    Science.gov (United States)

    Dolan, Kirk D; Mishra, Dharmendra K

    2013-01-01

    Modeling includes two distinct parts, the forward problem and the inverse problem. The forward problem-computing y(t) given known parameters-has received much attention, especially with the explosion of commercial simulation software. What is rarely made clear is that the forward results can be no better than the accuracy of the parameters. Therefore, the inverse problem-estimation of parameters given measured y(t)-is at least as important as the forward problem. However, in the food science literature there has been little attention paid to the accuracy of parameters. The purpose of this article is to summarize the state of the art of parameter estimation in food science, to review some of the common food science models used for parameter estimation (for microbial inactivation and growth, thermal properties, and kinetics), and to suggest a generic method to standardize parameter estimation, thereby making research results more useful. Scaled sensitivity coefficients are introduced and shown to be important in parameter identifiability. Sequential estimation and optimal experimental design are also reviewed as powerful parameter estimation methods that are beginning to be used in the food science literature.

  13. Electron and Phonon Transport in Molecular Junctions

    DEFF Research Database (Denmark)

    Li, Qian

    transmission at the Fermi energy. We propose and analyze a way of using π   stacking to design molecular junctions to control heat transport. We develop a simple model system to identify optimal parameter regimes and then use density functional theory (DFT) to extract model parameters for a number of specific....... The system we are interested in here are π-stacked molecules connected with two semi-infinite leads. π-stacked aromatic rings, connected via π-π electronic coupling, provides a rather soft mechanical bridge while maintaining high electronic conductivity. We investigate electron transport...... and the thermoelectric response of five representative π-stacked systems. We find that the transmission and power factor are both enhanced by increasing the conjugation length or adding substituent groups. The local transmission shows that several extra paths are added by cyano groups, which increases the total...

  14. Brownian Ratchets: Transport Controlled by Thermal Noise

    Science.gov (United States)

    Kula, J.; Czernik, T.; Łuczka, J.

    1998-02-01

    We analyze directed transport of overdamped Brownian particles in a 1D spatially periodic potential that are subjected to both zero-mean thermal equilibrium Nyquist noise and zero-mean exponentially correlated dichotomous fluctuations. We show that particles can reverse the direction of average motion upon a variation of noise parameters if two fundamental symmetries, namely, the reflection symmetry of the spatial periodic structure, and the statistical symmetry of dichotomous fluctuations, are broken. There is a critical thermal noise intensity Dc, or equivalently a critical temperature Tc, at which the mean velocity of particles is zero. Below Tc and above Tc particles move in opposite directions. At fixed temperature, there is a region of noise parameters in which particles of different linear size are transported in opposite directions.

  15. Flux saturation length of sediment transport.

    Science.gov (United States)

    Pähtz, Thomas; Kok, Jasper F; Parteli, Eric J R; Herrmann, Hans J

    2013-11-22

    Sediment transport along the surface drives geophysical phenomena as diverse as wind erosion and dune formation. The main length scale controlling the dynamics of sediment erosion and deposition is the saturation length Ls, which characterizes the flux response to a change in transport conditions. Here we derive, for the first time, an expression predicting Ls as a function of the average sediment velocity under different physical environments. Our expression accounts for both the characteristics of sediment entrainment and the saturation of particle and fluid velocities, and has only two physical parameters which can be estimated directly from independent experiments. We show that our expression is consistent with measurements of Ls in both aeolian and subaqueous transport regimes over at least 5 orders of magnitude in the ratio of fluid and particle density, including on Mars.

  16. Bedload transport of small rivers in Malaysia

    Institute of Scientific and Technical Information of China (English)

    Zahra ZANGENEH SIRDARI; Aminuddin AB GHANI; Zorkeflee Abu HASSAN

    2014-01-01

    Numerous time-consuming equations, based on the relationship between the reliability and representativeness of the data utilized in defining variables and constants, require complex parameters to estimate bedload transport. In this study the easily accessible data including flow discharge, water depth, water surface slope, and surface grain diameter (d50) from small rivers in Malaysia were used to estimate bedload transport. Genetic programming (GP) and artificial neural network (ANN) models are applied as complementary tools to estimate bed load transport based on a balance between simplicity and accuracy in small rivers. The developed models demonstrate higher performance with an overall accuracy of 97% and 93% for ANN and GP, respectively compared with other traditional methods and empirical equations.

  17. Globalisation and transport

    Energy Technology Data Exchange (ETDEWEB)

    Ubbels, B.; Rodenburg, C.; Nijkamp, P. [Department of Spatial Economics, Vrije Universiteit, Amsterdam (Netherlands)

    2001-02-01

    The relationship between globalisation and traffic volume is a complex one for many reasons. The transport sector is influenced by a variety of developments at different scales. Increasing incomes, more leisure time, new technology and a greying population are only a few examples of trends that are influencing future developments in transport and traffic. The future of transport is thus very uncertain. The project GITAGE (Globalisation, International Transport and the Global Environment) is being conducted by the Vrije Universteit Amsterdam, TRAIL (Delft University), the Netherlands Central Planning Bureau (CPB) and IVM (Institute for Environmental Studies). It was within this context that a layered assessment model was used to attempt to chart the possible influence of globalisation on the transport sector in terms of transport flows: and CO2 emissions. Four future scenarios at different scales (Global, European and Netherlands) produced virtually everywhere a (steep) rise in transport and emissions. The introduction of focused policy can change this picture. In fact, however, in most cases only a combination of stringent environmental policy and an environmentally conscious vision of the future can lead to a decline in CO2 emissions between 1995 and 2020.

  18. Information transport in multiplex networks

    CERN Document Server

    Pu, Cunlai; Yang, Xianxia; Yang, Jian

    2015-01-01

    In this paper, we study information transport in multiplex networks comprised of two coupled subnetworks. The upper subnetwork, called the logical layer, employs the shortest paths protocol to determine the logical paths for packets transmission, while the lower subnetwork acts as the physical layer, in which packets are delivered by the biased random walk mechanism characterized with a parameter $\\alpha$. Through simulation, we obtain the optimal $\\alpha$ corresponding to the maximum network lifetime and the maximum number of the arrival packets. Assortative coupling is better than the random coupling and the disassortative coupling, since it achieves much better transmission performances. Generally, the more homogeneous the lower subnetwork, the better the transmission performances are, which is opposite for the upper subnetwork. Finally, we propose an attack centrality for nodes based on the topological information of both subnetworks, and further investigate the transmission performances under targeted at...

  19. Transports and environment; Transports et environnements

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2004-07-01

    In the framework of the greenhouse gases reduction, this study proposes many advices to control the fuel consumption of the vehicles and to change habits in the transportation sector. It presents also the alternatives to the pollutant today vehicles in the domain of the vehicles and buses fuels but also the new motors. Many Internet addresses are provided to complete the presentation. (A.L.B.)

  20. The energetic alpha particle transport method EATM

    Energy Technology Data Exchange (ETDEWEB)

    Kirkpatrick, R.C.

    1998-02-01

    The EATM method is an evolving attempt to find an efficient method of treating the transport of energetic charged particles in a dynamic magnetized (MHD) plasma for which the mean free path of the particles and the Larmor radius may be long compared to the gradient lengths in the plasma. The intent is to span the range of parameter space with the efficiency and accuracy thought necessary for experimental analysis and design of magnetized fusion targets.

  1. Transport Imaging in the One Dimensional Limit

    Science.gov (United States)

    2006-06-01

    Bracewell, R., The Fourier Transform and Its Applications, 3rd ed. (McGraw-Hill, New York, 1999) 13. Arfken , G. B., Weber, H. J., Mathematical ... method makes it possible to extract key materials parameters, such as diffusion lengths and minority carrier mobility, from a single charge coupled...transport imaging technique will be expanded to examine spatial luminescence from 1D structures in order to develop a contact free method of measuring

  2. Parameter estimation for lithium ion batteries

    Science.gov (United States)

    Santhanagopalan, Shriram

    With an increase in the demand for lithium based batteries at the rate of about 7% per year, the amount of effort put into improving the performance of these batteries from both experimental and theoretical perspectives is increasing. There exist a number of mathematical models ranging from simple empirical models to complicated physics-based models to describe the processes leading to failure of these cells. The literature is also rife with experimental studies that characterize the various properties of the system in an attempt to improve the performance of lithium ion cells. However, very little has been done to quantify the experimental observations and relate these results to the existing mathematical models. In fact, the best of the physics based models in the literature show as much as 20% discrepancy when compared to experimental data. The reasons for such a big difference include, but are not limited to, numerical complexities involved in extracting parameters from experimental data and inconsistencies in interpreting directly measured values for the parameters. In this work, an attempt has been made to implement simplified models to extract parameter values that accurately characterize the performance of lithium ion cells. The validity of these models under a variety of experimental conditions is verified using a model discrimination procedure. Transport and kinetic properties are estimated using a non-linear estimation procedure. The initial state of charge inside each electrode is also maintained as an unknown parameter, since this value plays a significant role in accurately matching experimental charge/discharge curves with model predictions and is not readily known from experimental data. The second part of the dissertation focuses on parameters that change rapidly with time. For example, in the case of lithium ion batteries used in Hybrid Electric Vehicle (HEV) applications, the prediction of the State of Charge (SOC) of the cell under a variety of

  3. Transport Coefficients of Fluids

    CERN Document Server

    Eu, Byung Chan

    2006-01-01

    Until recently the formal statistical mechanical approach offered no practicable method for computing the transport coefficients of liquids, and so most practitioners had to resort to empirical fitting formulas. This has now changed, as demonstrated in this innovative monograph. The author presents and applies new methods based on statistical mechanics for calculating the transport coefficients of simple and complex liquids over wide ranges of density and temperature. These molecular theories enable the transport coefficients to be calculated in terms of equilibrium thermodynamic properties, and the results are shown to account satisfactorily for experimental observations, including even the non-Newtonian behavior of fluids far from equilibrium.

  4. Transporte del paciente politraumatizado

    OpenAIRE

    J. López Bayón; A. Medina Villanueva; A. Concha Torre

    2008-01-01

    Tal como se ha explicado en otros capítulos, en el paciente pediátrico politraumatizado es fundamental una buena evaluación y reanimación inicial. Pero tan importante como estos puntos son la categorización y el transporte al centro más adecuado para un tratamiento definitivo. Por otra parte, el niño tiene unas características físicas y fisiológicas muy diferentes que hacen que el transporte pediátrico y la ventilación mecánica (VM) durante dicho transporte tengan una serie de particulari...

  5. Quantum Transport in Semiconductors

    Science.gov (United States)

    1991-10-01

    SRS i 91 4. TITLE AND SUBTITLE Quantum Transport in Semiconductors 5. FUNDING NUMBER söMtos-rizk-ooss 6. AUTHOR(S) D. K. Ferry ©fte ELECTE...OF ABSTRACT UL NSN 7540-01-280-5500 O 1 9 Standard Form 298 (Rev. 2-89) Presented by ANSI Std «9-18 298-102 Final Report Quantum Transport in... Quantum Transport in Semiconductor Devices This final report describes a program of research investigating quantum effects which become important in

  6. Inositol transport proteins.

    Science.gov (United States)

    Schneider, Sabine

    2015-04-28

    The cyclic polyol myo-inositol is a key molecule in many different metabolic pathways among all organisms; in addition, it is fundamental for osmotic balance in the mammalian brain. This review sums up inositol transporters from eukaryotic organisms, elucidating their vital role in regulating the intracellular distribution and uptake of inositol. They can be divided into two groups according to their transport mechanisms: (1) sodium ion coupled inositol transporters that belong to the Solute Carrier Families 5 and 6-like Superfamily and, (2) proton coupled inositol symporters that are members of the Major Facilitator Superfamily. Intriguingly members of both families offer promising targets for medical treatment of a variety of diseases.

  7. Critical care transport.

    Science.gov (United States)

    Williams, Kenneth A; Sullivan, Francis M

    2013-12-03

    Critical care transport (CCT) is the segment of the Emergency Medical Services (EMS) system that transports patients who are critically ill or injured. Nearly 1,000 medical helicopters affiliated with over 300 transport programs, hundreds of fixed-wing aircraft, and many, many ground ambulances assisting adult, pediatric and neonatal CCT teams are operating in the United States.1 This article reviews the history of and indications for CCT, team qualifications, vehicle options, safety, CCT system design, and physician involvement in CCT. It concludes with a brief review of CCT services in Rhode Island.

  8. Numerical modeling of watershed-scale radiocesium transport coupled with biogeochemical cycling in forests

    Science.gov (United States)

    Mori, K.; Tada, K.; Tawara, Y.; Tosaka, H.; Ohno, K.; Asami, M.; Kosaka, K.

    2015-12-01

    Since the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, intensive monitoring and modeling works on radionuclide transfer in environment have been carried out. Although Cesium (Cs) concentration has been attenuating due to both physical and environmental half-life (i.e., wash-off by water and sediment), the attenuation rate depends clearly on the type of land use and land cover. In the Fukushima case, studying the migration in forest land use is important for predicting the long-term behavior of Cs because most of the contaminated region is covered by forests. Atmospheric fallout is characterized by complicated behavior in biogeochemical cycle in forests which can be described by biotic/abiotic interactions between many components. In developing conceptual and mathematical model on Cs transfer in forest ecosystem, defining the dominant components and their interactions are crucial issues (BIOMASS, 1997-2001). However, the modeling of fate and transport in geosphere after Cs exports from the forest ecosystem is often ignored. An integrated watershed modeling for simulating spatiotemporal redistribution of Cs that includes the entire region from source to mouth and surface to subsurface, has been recently developed. Since the deposited Cs can migrate due to water and sediment movement, the different species (i.e., dissolved and suspended) and their interactions are key issues in the modeling. However, the initial inventory as source-term was simplified to be homogeneous and time-independent, and biogeochemical cycle in forests was not explicitly considered. Consequently, it was difficult to evaluate the regionally-inherent characteristics which differ according to land uses, even if the model was well calibrated. In this study, we combine the different advantages in modeling of forest ecosystem and watershed. This enable to include more realistic Cs deposition and time series of inventory can be forced over the land surface. These processes are integrated

  9. Exciton Transport in Organic Semiconductors

    Science.gov (United States)

    Menke, Stephen Matthew

    Photovoltaic cells based on organic semiconductors are attractive for their use as a renewable energy source owing to their abundant feedstock and compatibility with low-cost coating techniques on flexible substrates. In contrast to photovoltaic cells based traditional inorganic semiconductors, photon absorption in an organic semiconductor results in the formation of a coulombically bound electron-hole pair, or exciton. The transport of excitons, consequently, is of critical importance as excitons mediate the interaction between charge and light in organic photovoltaic cells (OPVs). In this dissertation, a strong connection between the fundamental photophysical parameters that control nanoscopic exciton energy transfer and the mesoscopic exciton transport is established. With this connection in place, strategies for enhancing the typically short length scale for exciton diffusion (L D) can be developed. Dilution of the organic semiconductor boron subphthalocyanine chloride (SubPc) is found to increase the LD for SubPc by 50%. In turn, OPVs based on dilute layers of SubPc exhibit a 30% enhancement in power conversion efficiency. The enhancement in power conversion efficiency is realized via enhancements in LD, optimized optical spacing, and directed exciton transport at an exciton permeable interface. The role of spin, energetic disorder, and thermal activation on L D are also addressed. Organic semiconductors that exhibit thermally activated delayed fluorescence and efficient intersystem and reverse intersystem crossing highlight the balance between singlet and triplet exciton energy transfer and diffusion. Temperature dependent measurements for LD provide insight into the inhomogeneously broadened exciton density of states and the thermal nature of exciton energy transfer. Additional topics include energy-cascade OPV architectures and broadband, spectrally tunable photodetectors based on organic semiconductors.

  10. Interfacial area transport in bubbly flow

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, M.; Wu, Q.; Revankar, S.T. [Purdue Univ., West Lafayette, IN (United States)] [and others

    1997-12-31

    In order to close the two-fluid model for two-phase flow analyses, the interfacial area concentration needs to be modeled as a constitutive relation. In this study, the focus was on the investigation of the interfacial area concentration transport phenomena, both theoretically and experimentally. The interfacial area concentration transport equation for air-water bubbly up-flow in a vertical pipe was developed, and the models for the source and sink terms were provided. The necessary parameters for the experimental studies were identified, including the local time-averaged void fraction, interfacial area concentration, bubble interfacial velocity, liquid velocity and turbulent intensity. Experiments were performed with air-water mixture at atmospheric pressure. Double-sensor conductivity probe and hot-film probe were employed to measure the identified parameters. With these experimental data, the preliminary model evaluation was carried out for the simplest form of the developed interfacial area transport equation, i.e., the one-dimensional transport equation.

  11. Hydrologic transport and partitioning of phosphorus fractions

    Science.gov (United States)

    Berretta, C.; Sansalone, J.

    2011-06-01

    SummaryPhosphorus (P) in rainfall-runoff partitions between dissolved and particulate matter (PM) bound phases. This study investigates the transport and partitioning of P to PM fractions in runoff from a landscaped and biogenically-loaded carpark in Gainesville, FL (GNV). Additionally, partitioning and concentration results are compared to a similarly-sized concrete-paved source area of a similar rainfall depth frequency distribution in Baton Rouge, LA (BTR), where in contrast vehicular traffic represents the main source of pollutants. Results illustrate that concentrations of P fractions (dissolved, suspended, settleable and sediment) for GNV are one to two orders of magnitude higher than BTR. Despite these differences the dissolved fraction ( f d) and partitioning coefficient ( K d) distributions are similar, illustrating that P is predominantly bound to PM fractions. Examining PM size fractions, specific capacity for P (PSC) indicates that the P concentration order is suspended > settleable > sediment for GNV, similarly to BTR. For GNV the dominant PM mass fraction is sediment (>75 μm), while the mass of P is distributed predominantly between sediment and suspended (<25 μm) fractions since these PM mass fractions dominated the settleable one. With respect to transport of PM and P fractions the predominance of events for both areas is mass-limited first-flush, although each fraction illustrated unique washoff parameters. However, while transport is predominantly mass-limited, the transport of each PM and P fraction is influenced by separate hydrologic parameters.

  12. Optimal cytoplasmic transport in viral infections.

    Directory of Open Access Journals (Sweden)

    Maria R D'Orsogna

    Full Text Available For many viruses, the ability to infect eukaryotic cells depends on their transport through the cytoplasm and across the nuclear membrane of the host cell. During this journey, viral contents are biochemically processed into complexes capable of both nuclear penetration and genomic integration. We develop a stochastic model of viral entry that incorporates all relevant aspects of transport, including convection along microtubules, biochemical conversion, degradation, and nuclear entry. Analysis of the nuclear infection probabilities in terms of the transport velocity, degradation, and biochemical conversion rates shows how certain values of key parameters can maximize the nuclear entry probability of the viral material. The existence of such "optimal" infection scenarios depends on the details of the biochemical conversion process and implies potentially counterintuitive effects in viral infection, suggesting new avenues for antiviral treatment. Such optimal parameter values provide a plausible transport-based explanation of the action of restriction factors and of experimentally observed optimal capsid stability. Finally, we propose a new interpretation of how genetic mutations unrelated to the mechanism of drug action may nonetheless confer novel types of overall drug resistance.

  13. EBS Radionuclide Transport Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    J.D. Schreiber

    2005-08-25

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in ''Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration'' (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment for the license application (TSPA-LA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA-LA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport

  14. Effect of Correlations Between Model Parameters and Nuisance Parameters When Model Parameters are Fit to Data

    CERN Document Server

    Roe, Byron

    2013-01-01

    The effect of correlations between model parameters and nuisance parameters is discussed, in the context of fitting model parameters to data. Modifications to the usual $\\chi^2$ method are required. Fake data studies, as used at present, will not be optimum. Problems will occur for applications of the Maltoni-Schwetz \\cite{ms} theorem. Neutrino oscillations are used as examples, but the problems discussed here are general ones, which are often not addressed.

  15. Median statistics cosmological parameter values

    Energy Technology Data Exchange (ETDEWEB)

    Crandall, Sara, E-mail: sara1990@ksu.edu; Ratra, Bharat, E-mail: ratra@phys.ksu.edu

    2014-05-01

    We present median statistics central values and ranges for 12 cosmological parameters, using 582 measurements (published during 1990–2010) collected by [9]. On comparing to the recent Planck Collaboration [1] estimates of 11 of these parameters, we find good consistency in ten cases.

  16. Free flight in parameter space

    DEFF Research Database (Denmark)

    Dahlstedt, Palle; Nilsson, Per Anders

    2008-01-01

    The well-known difficulty of controlling many synthesis parameters in performance, for exploration and expression, is addressed. Inspired by interactive evolution, random vectors in parameter space are assigned to an array of pressure sensitive pads. Vectors are scaled with pressure and added to ...

  17. Methods for investigating parameter redundancy

    Directory of Open Access Journals (Sweden)

    Gimenez, O.

    2004-06-01

    Full Text Available The quantitative study of marked individuals relies mainly on the use of meaningful biological models. Classical inference is then conducted based on the model likelihood, parameterized by parameters such as survival, recovery, transition and recapture probabilities. In classical statistics, we seek parameter estimates by maximising the likelihood. However, models are often overparameterized and, as a consequence, some parameters cannot be estimated separately. Identifying how many and which (functions of parameters are estimable is thus crucial not only for proper model selection based upon likelihood ratio tests or information criteria but also for the interpretation of the estimates obtained. In this paper, we provide the reader with a description of the tools available to check for parameter redundancy. We aim to assist people in choosing the most appropriate method to solve their own specific problems.

  18. Generating three-parameter sensor

    Directory of Open Access Journals (Sweden)

    Filinyuk M. A.

    2014-08-01

    Full Text Available Generating sensors provide the possibility of getting remote information and its easy conversion into digital form. Typically, these are one-parameter sensors formed by combination of a primary transmitter (PT and a sine wave generator. Two-parameter sensors are not widely used as their implementation causes a problem with ambiguity output when measuring the PT. Nevertheless, the problem of creating miniature, thrifty multi-parameter RF sensors for different branches of science and industry remains relevant. Considering ways of designing RF sensors, we study the possibility of constructing a three-parameter microwave radio frequency range sensor, which is based on a two-stage three-parameter generalized immitance convertor (GIC. Resistive, inductive and capacitive PT are used as sensing elements. A mathematical model of the sensor, which describes the relation of the sensor parameters to the parameters of GIC and PT was developed. The basic parameters of the sensor, its transfer function and sensitivity were studied. It is shown that the maximum value of the power generated signal will be observed at a frequency of 175 MHz, and the frequency ranges depending on the parameters of the PT will be different. Research results and adequacy of the mathematical model were verified by the experiment. Error of the calculated dependences of the lasing frequency on PT parameters change, compared with the experimental data does not exceed 2 %. The relative sensitivity of the sensor based on two-stage GIC showed that for the resistive channel it is about 1.88, for the capacitive channel –1,54 and for the inductive channel –11,5. Thus, it becomes possible to increase the sensor sensitivity compared with the sensitivity of the PT almost 1,2—2 times, and by using the two stage GIC a multifunctional sensor is provided.

  19. The Healthy Worker Survivor Effect: Target Parameters and Target Populations.

    Science.gov (United States)

    Brown, Daniel M; Picciotto, Sally; Costello, Sadie; Neophytou, Andreas M; Izano, Monika A; Ferguson, Jacqueline M; Eisen, Ellen A

    2017-07-15

    We offer an in-depth discussion of the time-varying confounding and selection bias mechanisms that give rise to the healthy worker survivor effect (HWSE). In this update of an earlier review, we distinguish between the mechanisms collectively known as the HWSE and the statistical bias that can result. This discussion highlights the importance of identifying both the target parameter and the target population for any research question in occupational epidemiology. Target parameters can correspond to hypothetical workplace interventions; we explore whether these target parameters' true values reflect the etiologic effect of an exposure on an outcome or the potential impact of enforcing an exposure limit in a more realistic setting. If a cohort includes workers hired before the start of follow-up, HWSE mechanisms can limit the transportability of the estimates to other target populations. We summarize recent publications that applied g-methods to control for the HWSE, focusing on their target parameters, target populations, and hypothetical interventions.

  20. Economical Logistics Transportation planning Case

    Institute of Scientific and Technical Information of China (English)

    王蓉

    2014-01-01

    Transportation is one of the most important nodes of supply chain. Economical transportation planning enables enterprises to reduce cost and perhaps optimize supply chain. This report clarifies the optimization of the transport node with a door-door project.

  1. Prehospital transported patients

    DEFF Research Database (Denmark)

    Bech, Camilla Louise Nørgaard; Brabrand, M.; Lassen, Annmarie Touborg

    2015-01-01

    Introduction The survival of patients transported by ambulance to the emergency department (ED) depends on clinical conditions, patient-related factors and organisational prehospital set up. Data and information concerning patients in the prehospital system could form a valuable resource for asse......Introduction The survival of patients transported by ambulance to the emergency department (ED) depends on clinical conditions, patient-related factors and organisational prehospital set up. Data and information concerning patients in the prehospital system could form a valuable resource......-time ambulance transport to the ED at Odense University Hospital in the period 1 April 2012 to 30 September 2013. Ambulance personnel recorded vital signs and other clinical findings on a structured form on paper during the ambulance transport. Each contact was linked to information from population...

  2. Molecular electronic junction transport

    DEFF Research Database (Denmark)

    Solomon, Gemma C.; Herrmann, Carmen; Ratner, Mark

    2012-01-01

    Whenasinglemolecule,oracollectionofmolecules,isplacedbetween two electrodes and voltage is applied, one has a molecular transport junction. We discuss such junctions, their properties, their description, and some of their applications. The discussion is qualitative rather than quantitative, and f...

  3. Cooperative Transport Planning

    NARCIS (Netherlands)

    Zutt, J.; De Weerdt, M.M.

    2000-01-01

    To test and compare different forms of cooperative planning algorithms developed in the CABS project we use a generic simulator called MARS. Examples in the transportation sector are implemented in this simulator.

  4. Transportation Security Administration

    Science.gov (United States)

    ... content Official website of the Department of Homeland Security Transportation Security Administration A - Z Index What Can I Bring? ... form Search the Site Main menu Administrator Travel Security Screening Special Procedures TSA Pre✓® Passenger Support Travel ...

  5. Urban transportation projects conceptualised:

    DEFF Research Database (Denmark)

    Pineda, Andres Felipe Valderrama

    During the last ten years two innovations in urban transportation have been accomplished in two different parts of the planet: in the city of Bogotá, in Colombia, the first mass bus rapid transit system was designed, built and put into operation becoming the most visible icon of a great urban...... is straightforward: transportation projects transform cities. The paradoxical reality thus is that a problem that has been traditionally conceptualized in technical terms (transportation engineering, transportation economics, planning theory, traffic engineering, urban planning, etc.), has tremendous consequences...... idea underlying all this approaches is that cities, policies and their support systems co-evolve in permanent interaction shaping one another. Thus, if change is to be produced in desired ways actions must be taken in all fronts to render a desired result. In a wider perspective this approach to urban...

  6. Transportation Emissions: some basics

    DEFF Research Database (Denmark)

    Kontovas, Christos A.; Psaraftis, Harilaos N.

    2016-01-01

    Transportation is the backbone of international trade and a key engine driving globalization. However, there is growing concern that the Earth’s atmospheric composition is being altered by human activities, including transportation, which can lead to climate change. Air pollution from...... transportation and especially carbon dioxide emissions are at the center stage of discussion by the world community through various international treaties, such as the Kyoto Protocol. The transportation sector also emits non-CO2 pollutants that have important effects on air quality, climate, and public health...... and its contribution to climate change. In addition, this chapter presents the basics of environmental policy measures. In that context, we describe a way to measure the cost-effectiveness of various measures through the so-called Marginal Abatement Cost (MAC). Finally, the chapter deals with the topic...

  7. Energy and transportation(*

    Directory of Open Access Journals (Sweden)

    Hermans J.

    2015-01-01

    Full Text Available Transportation takes a considerable and increasing fraction of the energy use worldwide, and more than half the oil consumption. By far the largest part is used by cars powered by internal combustion engines. The advantage of using internal combustion engines is that the energy density of liquid fuels is extremely high. The disadvantage is that gasoline and diesel engines have a poor performance: 20 to 25% only. How does this compare with electric cars? What are the alternative transportation systems and their efficiencies anyway? In this lecture we analyse the efficiency of various transport systems, using elementary physics principles. We will look at cars, buses, trains and TGVs, ships and aircraft. In addition, the efficiency of human powered vehicles will be considered. New and promising developments in the field of Intelligent Transportation Systems, like Cooperative Adaptive Cruise Control, are also discussed.

  8. Planning Public Transport

    DEFF Research Database (Denmark)

    Andersen, Jonas Lohmann Elkjær; Landex, Alex

    2009-01-01

    This good practice guide is composed for the master course 13120 Public Transport Planning held at the Department of Transport, Technical University of Denmark. It is intended to use as guide in the different planning aspects and assignments of the course. Since the course is about the planning...... of new public transport infrastructure this guide also focuses on the planning of new infrastructure. Furthermore, the new infrastructure in the course is expected to be a light rail and even though this guide aims at being general for public transport some of the issues evidently become more relevant...... for light rail. A light rail system is chosen as focus because light rail systems generally have higher impacts in the traffic modeling than busses and are more challenging in the planning than urban rail and metro. This is emanated by the assumption that a capability for planning light rail inevitable...

  9. Appraisal of Transport Projects

    DEFF Research Database (Denmark)

    Jensen, Anders Vestergaard

    The evaluation of transport projects has traditionally been based on quantitative descriptions of selected impacts by the use of cost-benefit analysis (CBA). However, environmental impacts are now taking into consideration when decisions have to be made, regarding which large transport projects...... complexity. Optimisation has been replaced with satisficing, where satisficing is defined as finding an acceptable or satisfactory solution to a problem instead of a socio-economical optimal solution. This calls for new approaches of appraising transport projects that goes beyond what the classical CBA......, seems suitable for. As a result of the above mentioned issues regarding conflict of interests, multiple impacts, participation of stakeholders, and sustainability, additional approaches for appraisal have been suggested. Multi-criteria decision analysis (MCDA) has been introduced in the transport...

  10. Appraisal of Transport Projects

    DEFF Research Database (Denmark)

    Jensen, Anders Vestergaard

    be dealt with by the use of sensitivity analysis and robustness measures. This also calls for an appraisal methodology which is transparent and able to include the different preferences among experts, the public, and stakeholders. This PhD thesis has three main focuses concerning appraisal of transport...... papers written during the PhD study. The potential for transport appraisal demonstrated in this PhD study can be listed in the following main findings. • To reconcile socio-economic analysis and public acceptance it can be recommended to widen the appraisal methodology. • When widening the appraisal......The evaluation of transport projects has traditionally been based on quantitative descriptions of selected impacts by the use of cost-benefit analysis (CBA). However, environmental impacts are now taking into consideration when decisions have to be made, regarding which large transport projects...

  11. Transport statistics 1996

    CSIR Research Space (South Africa)

    Shepperson, L

    1997-12-01

    Full Text Available This publication contains transport and related statistics on roads, vehicles, infrastructure, passengers, freight, rail, air, maritime and road traffic, and international comparisons. The information compiled in this publication has been gathered...

  12. Urban regeneration and transportation

    CSIR Research Space (South Africa)

    Van Wyk, Llewellyn V

    2011-01-01

    Full Text Available The built environment is the stage upon which we live out our daily lives: the built environment comprises urban design, land use, and the transportation system, and the patterns of human activity within this physical environment. Unfortunately...

  13. Crew Transportation Operations Standards

    Science.gov (United States)

    Mango, Edward J.; Pearson, Don J. (Compiler)

    2013-01-01

    The Crew Transportation Operations Standards contains descriptions of ground and flight operations processes and specifications and the criteria which will be used to evaluate the acceptability of Commercial Providers' proposed processes and specifications.

  14. Animal transportation networks.

    Science.gov (United States)

    Perna, Andrea; Latty, Tanya

    2014-11-01

    Many group-living animals construct transportation networks of trails, galleries and burrows by modifying the environment to facilitate faster, safer or more efficient movement. Animal transportation networks can have direct influences on the fitness of individuals, whereas the shape and structure of transportation networks can influence community dynamics by facilitating contacts between different individuals and species. In this review, we discuss three key areas in the study of animal transportation networks: the topological properties of networks, network morphogenesis and growth, and the behaviour of network users. We present a brief primer on elements of network theory, and then discuss the different ways in which animal groups deal with the fundamental trade-off between the competing network properties of travel efficiency, robustness and infrastructure cost. We consider how the behaviour of network users can impact network efficiency, and call for studies that integrate both network topology and user behaviour. We finish with a prospectus for future research.

  15. CHARTB multigroup transport package

    Energy Technology Data Exchange (ETDEWEB)

    Baker, L.

    1979-03-01

    The physics and numerical implementation of the radiation transport routine used in the CHARTB MHD code are discussed. It is a one-dimensional (Cartesian, cylindrical, and spherical symmetry), multigroup,, diffusion approximation. Tests and applications will be discussed as well.

  16. Nebraska Department of Transportation

    Science.gov (United States)

    The EPA is providing notice of a proposed Administrative Penalty Assessment against the Nebraska Department of Transportation, a state agency located at 1500 Highway 2, Lincoln, NE 68509, for alleged violations of its municipal separate stormwater sewer sy

  17. Accident resistant transport container

    Science.gov (United States)

    Andersen, John A.; Cole, James K.

    1980-01-01

    The invention relates to a container for the safe air transport of plutonium having several intermediate wood layers and a load spreader intermediate an inner container and an outer shell for mitigation of shock during a hypothetical accident.

  18. MANAGEMENT OF TOURISM TRANSPORT

    Directory of Open Access Journals (Sweden)

    Gabriela Cecilia STĂNCIULESCU

    2016-06-01

    Full Text Available Undoubtedly, the relevance of transport activities in relation to tourism activities is essential, because it is extremely important and necessary to offer feasible information about tourism services to help consumer to choose the mode of travel to destinations ideal holiday. The methods used in the development of this hypothesis were explanation, exemplification (brief presentation of each mode of transport comparison etc. Analyzing the current situation of national, European and World Wide tourism transportation, the paper proposes practical applications able to explain that the conduct of economic activities as an integral part of the sector of trade and services within a national economy, would not be possible without the involvement of transport, whether by road, rail and air and naval. The results of the analysis are perfectly applicable offering guests the opportunity to reach the most remote corners of the world in a short time, high degree of comfort and affordable price.

  19. Animal transportation networks

    Science.gov (United States)

    Perna, Andrea; Latty, Tanya

    2014-01-01

    Many group-living animals construct transportation networks of trails, galleries and burrows by modifying the environment to facilitate faster, safer or more efficient movement. Animal transportation networks can have direct influences on the fitness of individuals, whereas the shape and structure of transportation networks can influence community dynamics by facilitating contacts between different individuals and species. In this review, we discuss three key areas in the study of animal transportation networks: the topological properties of networks, network morphogenesis and growth, and the behaviour of network users. We present a brief primer on elements of network theory, and then discuss the different ways in which animal groups deal with the fundamental trade-off between the competing network properties of travel efficiency, robustness and infrastructure cost. We consider how the behaviour of network users can impact network efficiency, and call for studies that integrate both network topology and user behaviour. We finish with a prospectus for future research. PMID:25165598

  20. Transportation Network Topologies

    Science.gov (United States)

    Holmes, Bruce J.; Scott, John

    2004-01-01

    A discomforting reality has materialized on the transportation scene: our existing air and ground infrastructures will not scale to meet our nation's 21st century demands and expectations for mobility, commerce, safety, and security. The consequence of inaction is diminished quality of life and economic opportunity in the 21st century. Clearly, new thinking is required for transportation that can scale to meet to the realities of a networked, knowledge-based economy in which the value of time is a new coin of the realm. This paper proposes a framework, or topology, for thinking about the problem of scalability of the system of networks that comprise the aviation system. This framework highlights the role of integrated communication-navigation-surveillance systems in enabling scalability of future air transportation networks. Scalability, in this vein, is a goal of the recently formed Joint Planning and Development Office for the Next Generation Air Transportation System. New foundations for 21st thinking about air transportation are underpinned by several technological developments in the traditional aircraft disciplines as well as in communication, navigation, surveillance and information systems. Complexity science and modern network theory give rise to one of the technological developments of importance. Scale-free (i.e., scalable) networks represent a promising concept space for modeling airspace system architectures, and for assessing network performance in terms of scalability, efficiency, robustness, resilience, and other metrics. The paper offers an air transportation system topology as framework for transportation system innovation. Successful outcomes of innovation in air transportation could lay the foundations for new paradigms for aircraft and their operating capabilities, air transportation system architectures, and airspace architectures and procedural concepts. The topology proposed considers air transportation as a system of networks, within which

  1. Bæredygtig transport

    DEFF Research Database (Denmark)

    Haas, Henning de; Søndergaard, Mads

    2009-01-01

    I denne artikel sættes fokus på bæredygtighed og transport. Baggrunden for artiklen er en undersøgelse af status for bæredygtig transport i et antal danske virksomheder i samarbejde med DHL. Indledningen giver en baggrund for fokus på bæredygtighed, efterfølgende sættes der fokus på "Green SCM...

  2. Sustainability - and sustainable transport

    Energy Technology Data Exchange (ETDEWEB)

    Thisgaard, P.

    1996-12-31

    To gain the fulfillment of basic sustainable objectives in a medium- and long-term perspective for transport. The necessary activities must be genuinely complementary i.e. it must solve problems within at least two sectors and at the same time this activity must be sustainable in a Brundtland report perspective. The transport sector must take steps to develop an `ECO-NOMY`. The principle here is a `fusion` of economy and ecology, and the first place this can take place is in the transport sector. This can only take place in a close cooperation between the transport sector and the other sectors of society. Methods to carry out cross-sectional priorities and allocation of resources must be developed in order to avoid societal sub-optimization of single issue solutions. Besides, a development of public administration must take place through a very heavy limitation of the principles of `sector thinking` as well as the carrying through of totally new principles in the selection of personnel as well as the principles of promotion and control. `Management by objectives` combined with an emphasis of certain moral codes - may contribute substantially to such a development. The principles are to economize with resources and as far as possible adjust the supply to a given demand with reasonable regard to comfort and transport considerations. Besides, the transport sector must try to solve other sector`s sociological problems and actively try to point out where other sectors create problems for the transport sector which prevent this in becoming `sustainable`. The transport sector must also continually try to forward its ability to change by avoiding capital investment or other forms of bindings which might hinder a different development if or when important technological changes occur. In a number of ways you can point to different concrete possibilities with the following headlines: diversification, integration, development of vehicles, information and concrete project areas

  3. Transporte forestal con cables

    OpenAIRE

    Anaya L. Héctor J.

    2012-01-01

    La explotación forestal es un problema fundamentalmente de transporte. El apeo y la preparación de las trozas, aunque a veces presentan algunas dificultades, son operaciones fáciles de resolver comparadas con la operación de transporte la cual absorbe del 60% al 70% o más del costo total del aprovechamiento del bosque. El 30% o 40% restante es absorbido por las faenas previas de apeo y troceo.

  4. [Recommendations for neonatal transport].

    Science.gov (United States)

    Moreno Hernando, J; Thió Lluch, M; Salguero García, E; Rite Gracia, S; Fernández Lorenzo, J R; Echaniz Urcelay, I; Botet Mussons, F; Herranz Carrillo, G; Sánchez Luna, M

    2013-08-01

    During pregnancy, it is not always possible to identify maternal or foetal risk factors. Infants requiring specialised medical care are not always born in centres providing intensive care and will need to be transferred to a referral centre where intensive care can be provided. Therefore Neonatal Transport needs to be considered as part of the organisation of perinatal health care. The aim of Neonatal Transport is to transfer a newborn infant requiring intensive care to a centre where specialised resources and experience can be provided for the appropriate assessment and continuing treatment of a sick newborn infant. Intrauterine transfer is the ideal mode of transport when the birth of an infant with risk factors is diagnosed. Unfortunately, not all problems can be detected in advance with enough time to safely transfer a pregnant woman. Around 30- 50% of risk factors will be diagnosed during labour or soon after birth. Therefore, it is important to have the knowledge and resources to resuscitate and stabilise a newborn infant, as well as a specialised neonatal transport system. With this specialised transport it is possible to transfer newly born infants with the same level of care that they would receive if they had been born in a referral hospital, without increasing their risks or affecting the wellbeing of the newborn. The Standards Committee of the Spanish Society of Neonatology reviewed and updated recommendations for intrauterine transport and indications for neonatal transfer. They also reviewed organisational and logistic factors involved with performing neonatal transport. The Committee review included the type of personnel who should be involved; communication between referral and receiving hospitals; documentation; mode of transport; equipment to stabilise newly born infants; management during transfer, and admission at the referral hospital.

  5. Membrane Transport Phenomena (MTP)

    Science.gov (United States)

    Mason, Larry W.

    1997-01-01

    The third semi-annual period of the MTP project has been involved with performing experiments using the Membrane Transport Apparatus (MTA), development of analysis techniques for the experiment results, analytical modeling of the osmotic transport phenomena, and completion of a DC-9 microgravity flight to test candidate fluid cell geometries. Preparations were also made for the MTP Science Concept Review (SCR), held on 13 June 1997 at Lockheed Martin Astronautics in Denver. These activities are detailed in the report.

  6. Transport of reservoir fines

    DEFF Research Database (Denmark)

    Yuan, Hao; Shapiro, Alexander; Stenby, Erling Halfdan

    Modeling transport of reservoir fines is of great importance for evaluating the damage of production wells and infectivity decline. The conventional methodology accounts for neither the formation heterogeneity around the wells nor the reservoir fines’ heterogeneity. We have developed an integral...... dispersion equation in modeling the transport and the deposition of reservoir fines. It successfully predicts the unsymmetrical concentration profiles and the hyperexponential deposition in experiments....

  7. Simulation of carrier transport through Single Wall Carbon Nanotubes(SWNT)

    OpenAIRE

    Rajesh Kumar; Ramlal Singh

    2011-01-01

    In this paper, it is observed & verified that the simulation of carrier transport through Carbon Nanotubes (CNTs) can be explained with the help of tool, “the Boltzmann transport simulator for CNTs”.By using this simulator, we examine the electronic transport quantities of SWNTs such as electric current, electric field, steady state potential, resistance of CNTs and (I-V) curve which is useful in device modeling of nanodevices and the transport quantities as a function of different parameters...

  8. Radionuclide transport behavior in a generic geological radioactive waste repository.

    Science.gov (United States)

    Bianchi, Marco; Liu, Hui-Hai; Birkholzer, Jens T

    2015-01-01

    We performed numerical simulations of groundwater flow and radionuclide transport to study the influence of several factors, including the ambient hydraulic gradient, groundwater pressure anomalies, and the properties of the excavation damaged zone (EDZ), on the prevailing transport mechanism (i.e., advection or molecular diffusion) in a generic nuclear waste repository within a clay-rich geological formation. By comparing simulation results, we show that the EDZ plays a major role as a preferential flowpath for radionuclide transport. When the EDZ is not taken into account, transport is dominated by molecular diffusion in almost the totality of the simulated domain, and transport velocity is about 40% slower. Modeling results also show that a reduction in hydraulic gradient leads to a greater predominance of diffusive transport, slowing down radionuclide transport by about 30% with respect to a scenario assuming a unit gradient. In addition, inward flow caused by negative pressure anomalies in the clay-rich formation further reduces transport velocity, enhancing the ability of the geological barrier to contain the radioactive waste. On the other hand, local high gradients associated with positive pressure anomalies can speed up radionuclide transport with respect to steady-state flow systems having the same regional hydraulic gradients. Transport behavior was also found to be sensitive to both geometrical and hydrogeological parameters of the EDZ. Results from this work can provide useful knowledge toward correctly assessing the post-closure safety of a geological disposal system. © 2014, National Ground Water Association.

  9. Classical transport in disordered systems

    Science.gov (United States)

    Papaioannou, Antonios

    This thesis reports on the manifestation of structural disorder on molecular transport and it consists of two parts. Part I discusses the relations between classical transport and the underlying structural complexity of the system. Both types of molecular diffusion, namely Gaussian and non- Gaussian are presented and the relevant time regimes are discussed. In addition the concept of structural universality is introduced and connected with the diffusion metrics. One of the most robust techniques for measuring molecular mean square displacements is magnetic resonance. This method requires encoding and subsequently reading out after an experimentally controlled time, a phase φ to the spins using magnetic field gradients. The main limitation for probing short diffusion lengths L(t) ˜ 1micro m with magnetic resonance is the requirement to encode and decode the phase φ in very short time intervals. Therefore, to probe such displacements a special probe was developed equipped with a gradient coil capable of delivering magnetic field gradients of approximately 90 G/cmA . The design of the probe is reported. Part I also includes a discussion of experiments of transport in two qualitatively different disordered phantoms and reports on a direct observation of universality in one-dimension. The results reveal the universal power law scaling of the diffusion coefficient at the long-time regime and illustrate the essence of structural universality by experimentally determining the structure correlation function of the phantoms. In addition, the scaling of the diffusive permeability of the phantoms with respect to the pore size is investigated. Additional work presented includes a detailed study of adsorption of methane gas in Vycor disordered glass. The techniques described in Part I of this thesis are widely used for measuring structural parameters of porous media, such as the surface-to-volume ratio or diffusive permeability. Part II of this thesis discusses the

  10. Extraction of important electrical parameters of CuO

    Energy Technology Data Exchange (ETDEWEB)

    Serin, T. [Department of Engineering Physics, Faculty of Engineering, Ankara University, 06100 Ankara (Turkey); Yildiz, A., E-mail: yildizab@gmail.co [Department of Physics, Faculty of Science and Arts, Ahi Evran University, 40040 Kirsehir (Turkey); Horzum Sahin, S.; Serin, N. [Department of Engineering Physics, Faculty of Engineering, Ankara University, 06100 Ankara (Turkey)

    2011-02-01

    Conductivity, X-ray diffraction (XRD), optical absorption and atomic force microscopy (AFM) measurements of CuO thin film were presented. Three distinct electrical conduction contributions with discrete characteristic activation energies were observed. The applicability of various theoretical models was considered to explain results on electrical transport. We extracted important electrical parameters of CuO, which might be useful for its gas sensor applications. -- Research Highlights: {yields} The important electrical parameters of CuO were extracted. Three distinct activation contributions were observed. {yields} Above 200 K, conductivity was controlled by potential barrier. {yields} Below 200 K, conductivity was described in terms of hopping conduction.

  11. Summary of overburden studies at Olkiluoto with an emphasis on geosphere-biosphere interface

    Energy Technology Data Exchange (ETDEWEB)

    Lahdenpera, A.-M.; Palmen, J.; Hella, P. [JP-Fintact Oy, Vantaa (Finland)

    2005-03-15

    The aim of this work is to synthesize the existing geotechnical, geochemical, mineralogical and hydraulic data from the overburden at the Olkiluoto site. The data has been collected in different studies as a part of the characterisation program for the disposal of spent nuclear fuel mainly during 1998-2004. Soil and peat samples from open test pits at various depths have been taken and analysed. The extent of the analyses programme has varied between the sampling. Quaternary deposits in the study area were studied in 13 soils test pits dug by excavator and four peat test cores. Standard procedures were applied in logging physical properties. Two extractions were used to emulate different environmental conditions in soils. Following determinations and chemical analyses were carried out: pH, water content, organic matter, anions (Cl, F, NO{sub 3} and SO{sub 4}) and metals (Al, Ca, Cs, Fe, K, Mg, Na, U and Sr). In addition, Summary tables most of the available physicochemical data from soil and peat samples were prepared. The hydraulic conductivity in overburden has been measured in the groundwater observation tubes (PVP-holes). The measurements were conducted by using the so called slug-test technique. The fluctuation of water table, dry top layer vs. ground surface elevation and dry top layer thickness vs. overburden thickness in shallow boreholes and uppermost levels of multi level piezometers (EP-holes) are also presented. (orig.)

  12. Arsenic sorption by nanocrystalline magnetite: an example of environmentally promising interface with geosphere.

    Science.gov (United States)

    Bujňáková, Z; Baláž, P; Zorkovská, A; Sayagués, M J; Kováč, J; Timko, M

    2013-11-15

    In this paper, the sorption of arsenic onto nanocrystalline magnetite mineral Fe3O4 was studied in a model system. Nanocrystalline magnetite was produced by mechanical activation in a planetary ball mill from natural microcrystalline magnetite. As a consequence of milling, the specific surface area increased from 0.1m(2)/g to 11.9 m(2)/g and the surface site concentration enhanced from 2.2 sites/nm(2) to 8.4 sites/nm(2). These changes in surface properties of magnetite lead to the enhancement of arsenic removal from model system. The best sorption ability was achieved with magnetite sample activated for 90 min. In this case the sample was able to absorb around 4 mg/g. The structural changes of magnetite were also observed and the new hematite phase was detected after 120 min of milling. A good correlation between the decreasing particle size, increasing specific surface area and reduction of saturation magnetization was found. In desorption study, KOH and NaOH were found as the best eluents where more than 70% of arsenic was released back into the solution. The principal novelty of the paper is that mineral magnetite, truly one nature's gift can be used after "smart" milling (mechanical activation) as an effective arsenic sorbent.

  13. The origin and nature of life on Earth the emergence of the fourth geosphere

    CERN Document Server

    Smith, Eric

    2016-01-01

    Uniting the conceptual foundations of the physical sciences and biology, this groundbreaking multidisciplinary book explores the origin of life as a planetary process. Combining geology, geochemistry, biochemistry, microbiology, evolution and statistical physics to create an inclusive picture of the living state, the authors develop the argument that the emergence of life was a necessary cascade of non-equilibrium phase transitions that opened new channels for chemical energy flow on Earth. This full colour and logically structured book introduces the main areas of significance and provides a well-ordered and accessible introduction to multiple literatures outside the confines of disciplinary specializations, as well as including an extensive bibliography to provide context and further reading. For researchers, professionals entering the field or specialists looking for a coherent overview, this text brings together diverse perspectives to form a unified picture of the origin of life and the ongoing organizat...

  14. Forsmark site investigation. Programme for further investigations of geosphere and biosphere

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-01-01

    Since the beginning of 2002, SKB (the Swedish Nuclear Fuel and Waste Management Co) has been conducting a site investigation in Forsmark in the municipality of Oesthammar for siting of the deep repository for spent nuclear fuel. An equivalent investigation is also being conducted at Simpevarp and Laxemar in Oskarshamn Municipality. SKB's goal is to submit an application under the Environmental Code and the Nuclear Activities Act for siting of the deep repository at one of these sites by the end of 2008/beginning of 2009. When the application is submitted, everything of importance for the deep repository's safety, constructability and environmental impact shall have been investigated and analyzed. The investigations shall also provide data as a basis for selecting a site and configuring the facility to suit conditions on the site.SKB submitted a programme for the initial site investigation in Forsmark at the end of 2001. The investigations described there have now been completed. This report describes the programme that has now been prepared for the remainder of the site investigation. The points of departure are the general goals for the Deep Repository Project during the site investigation phase, the data needed for evaluation of the site, plus experience and results from the work to date. The programme has been prepared with the support of investigation data as of August 2004. The investigations described here will, as before, be conducted with great consideration given to residents, property owners and natural and cultural values so that they are not unnecessarily exposed to impact or disturbances. Just as before, the programme will be continuously adapted to the knowledge that is gradually accumulated on the site. All important changes will be reported to the authorities and other concerned parties. The investigations that have been conducted (as of August 2004) and their results can be summarized in the following points: The surface characterization of the geological and ecological conditions in the area has largely been completed. In order to investigate the bedrock at depth, five deep (1,000 m) and two shallower cored boreholes have been drilled and documented. Drilling of a sixth deep cored borehole is under way. 19 percussion boreholes have been drilled, partly to supply core drilling with flushing water and partly to investigate the bedrock. A comprehensive, preliminary site description (version 1.1) has been published. The work of compiling all information from the initial site investigation is under way and will result in version 1.2 of the site description. The consultation process for a possible deep repository in Forsmark has been established in accordance with the provisions of the Environmental Code. An active information and communication programme has been established for ongoing dialogue with nearby residents, the public, Oesthammar Municipality, neighbouring municipalities and other local stakeholders.

  15. A software tool to assess uncertainty in transient-storage model parameters using Monte Carlo simulations

    Science.gov (United States)

    Ward, Adam S.; Kelleher, Christa A.; Mason, Seth J. K.; Wagener, Thorsten; McIntyre, Neil; McGlynn, Brian L.; Runkel, Robert L.; Payn, Robert A.

    2017-01-01

    Researchers and practitioners alike often need to understand and characterize how water and solutes move through a stream in terms of the relative importance of in-stream and near-stream storage and transport processes. In-channel and subsurface storage processes are highly variable in space and time and difficult to measure. Storage estimates are commonly obtained using transient-storage models (TSMs) of the experimentally obtained solute-tracer test data. The TSM equations represent key transport and storage processes with a suite of numerical parameters. Parameter values are estimated via inverse modeling, in which parameter values are iteratively changed until model simulations closely match observed solute-tracer data. Several investigators have shown that TSM parameter estimates can be highly uncertain. When this is the case, parameter values cannot be used reliably to interpret stream-reach functioning. However, authors of most TSM studies do not evaluate or report parameter certainty. Here, we present a software tool linked to the One-dimensional Transport with Inflow and Storage (OTIS) model that enables researchers to conduct uncertainty analyses via Monte-Carlo parameter sampling and to visualize uncertainty and sensitivity results. We demonstrate application of our tool to 2 case studies and compare our results to output obtained from more traditional implementation of the OTIS model. We conclude by suggesting best practices for transient-storage modeling and recommend that future applications of TSMs include assessments of parameter certainty to support comparisons and more reliable interpretations of transport processes.

  16. Fluctuations in some climate parameters

    CERN Document Server

    Erlykin, A D; Wolfendale, A W; 10.1016/j.jastp.2011.01.021

    2011-01-01

    There is argument as to the extent to which there has been an increase over the past few decades in the frequency of the extremes of climatic parameters, such as temperature, storminess, precipitation, etc, an obvious point being that Global Warming might be responsible. Here we report results on those parameters of which we have had experience during the last few years: Global surface temperature, Cloud Cover and the MODIS Liquid Cloud Fraction. In no case we have found indications that fluctuations of these parameters have increased with time.

  17. Multi-parameter Burau representations

    OpenAIRE

    Mohammad N. Abdulrahim; Madline Al- Tahan; Samer S. Habre

    2013-01-01

    We consider the multi-parameter representation of Artin's braid group introduced by D. D. Long and J. P. Tian, namely $\\alpha: B_{n}\\rightarrow GL_{m}(C)$, where $m=n!n$ . First, we show that there exists a complex specialization of the multi-parameter representation that does not arise from any Hecke algebra. Second, we find conditions under which the images of the generators of the braid group on three strings under the multi-parameter representation are unitary relative to a nonsingular he...

  18. Telemetry System of Biological Parameters

    Directory of Open Access Journals (Sweden)

    Jan Spisak

    2005-01-01

    Full Text Available The mobile telemetry system of biological parameters serves for reading and wireless data transfer of measured values of selected biological parameters to an outlying computer. It concerns basically long time monitoring of vital function of car pilot.The goal of this projects is to propose mobile telemetry system for reading, wireless transfer and processing of biological parameters of car pilot during physical and psychical stress. It has to be made with respect to minimal consumption, weight and maximal device mobility. This system has to eliminate signal noise, which is created by biological artifacts and disturbances during the data transfer.

  19. Bioreactor Mass Transport Studies

    Science.gov (United States)

    Kleis, Stanley J.; Begley, Cynthia M.

    1997-01-01

    The objectives of the proposed research efforts were to develop both a simulation tool and a series of experiments to provide a quantitative assessment of mass transport in the NASA rotating wall perfused vessel (RWPV) bioreactor to be flown on EDU#2. This effort consisted of a literature review of bioreactor mass transport studies, the extension of an existing scalar transport computer simulation to include production and utilization of the scalar, and the evaluation of experimental techniques for determining mass transport in these vessels. Since mass transport at the cell surface is determined primarily by the relative motion of the cell assemblage and the surrounding fluid, a detailed assessment of the relative motion was conducted. Results of the simulations of the motion of spheres in the RWPV under microgravity conditions are compared with flight data from EDU#1 flown on STS-70. The mass transport across the cell membrane depends upon the environment, the cell type, and the biological state of the cell. Results from a literature review of cell requirements of several scalars are presented. As a first approximation, a model with a uniform spatial distribution of utilization or production was developed and results from these simulations are presented. There were two candidate processes considered for the experimental mass transport evaluations. The first was to measure the dissolution rate of solid or gel beads. The second was to measure the induced fluorescence of beads as a stimulant (for example hydrogen peroxide) is infused into the vessel. Either technique would use video taped images of the process for recording the quantitative results. Results of preliminary tests of these techniques are discussed.

  20. Transport of radioactive materials; Transporte de materiais radioativos

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-11-15

    This ninth chapter presents de CNEN-NE--5.01 norm 'Transport of radioactive material'; the specifications of the radioactive materials for transport; the tests of the packages; the requests for controlling the transport and the responsibilities during the transport of radioactive material.