The Experts below are selected from a list of 294 Experts worldwide ranked by ideXlab platform
Ján Čelko - One of the best experts on this subject based on the ideXlab platform.
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Implementation of Transport Data in to the Transport Forecasting in Slovakia
Transportation Research Procedia, 2016Co-Authors: Marek Drličiak, Ján ČelkoAbstract:The Transport forecast is the unconditional part of every Transport studies, LOS capacity calculations or town Transport plans. It is processed for several time horizons or time intervals. The basic purpose of Transportation planning and management is to match Transportation supply with travel demand, which represents 'need'. A thorough understanding of existing travel pattern is necessary for identifying and analyzing existing traffic related problems. Detailed Data on current travel pattern and traffic volumes are needed also for developing travel forecasting/prediction models. The prediction of future travel demand is an essential task of the long-range Transportation planning process for determining strategies for accommodating future needs. Further sustainable mobility in Slovak cities, their competitiveness, economy as well as living conditions of inhabitants are depend also on the way of Transport planning, development of Transport infrastructure and services. Generally the calculation of the interzonal Transport relations (number of trips) is a challenge. The practical application of the Transport forecast theory is not easy. Some steps are hardly implemented to the practice for various reasons. The discrepancy between needed Data and available Data is one of the common problem. The traffic modelers must often study the method of Data gathering which use an institutions possessing of demanded Data. The discrepancies are showed on different levels (for examples the borders of urban zone and statistic area units are different in principle). One of the problematic issue is the definition of work trips or business trips. The origin and destination is defined at office address. The mobility survey contains Data characterized one household, people not admit usual mentioned trips. The official company address are different as Transport department. The ratio of these trips in traffic flow is not negligible. The article is aimed to brief description of the Transport forecast process calculation. The main part of the article describes outputs from mobility surveys of some regions of Slovakia and them implementation in Transport forecast calculation process. This methodically tool is intended for traffic analysis, planned solutions and arrangements verification of problem situations solutions. The University of Žilina processed several mobility surveys. The sample covers different regions with different gravity areas. The Database was detailed evaluated and compared. Two Slovak regions were modeled in the Visum software (PTV Vision). Output Data were used for town Transport plans. Other mobility surveys were made for analysis of interstate Transport relations (Slovak republic - Hungary).
Katsumi Hayashi - One of the best experts on this subject based on the ideXlab platform.
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Application of Improved Air Transport Data and Wall Transmission/Reflection Data in the SKYSHINE Code to Typical BWR Turbine Skyshine
Journal of Nuclear Science and Technology, 2000Co-Authors: Ryuichi Tayama, Hideo Hirayama, Yukio Sakamoto, Yoshiko Harima, Yoshihisa Hayashida, Makoto Nemoto, Satoshi Ishikawa, Osamu Sato, Katsumi HayashiAbstract:Three basic sets of Data, i.e. air Transport Data and material transmission/reflection Data, included in the SKYSHINE program have been improved using up-to-Data and methods, and applied to skyshine dose calculations for a typical BWR turbine building. The direct and skyshine dose rates with the original SKYSHINE code show good agreements with MCNP Monte-Calro calculations except for the distances less than 0.1 km. The results for the improved SKYSHINE code also have agreements with the MCNP code within 10 – 20 %. The discrepancy of 10 – 20 % can be due to the improved concrete transmission Data at small incident and exit angles. We still improve the three sets of Data and investigate with different calculational models to get more accurate results.
Marek Drličiak - One of the best experts on this subject based on the ideXlab platform.
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Implementation of Transport Data in to the Transport Forecasting in Slovakia
Transportation Research Procedia, 2016Co-Authors: Marek Drličiak, Ján ČelkoAbstract:The Transport forecast is the unconditional part of every Transport studies, LOS capacity calculations or town Transport plans. It is processed for several time horizons or time intervals. The basic purpose of Transportation planning and management is to match Transportation supply with travel demand, which represents 'need'. A thorough understanding of existing travel pattern is necessary for identifying and analyzing existing traffic related problems. Detailed Data on current travel pattern and traffic volumes are needed also for developing travel forecasting/prediction models. The prediction of future travel demand is an essential task of the long-range Transportation planning process for determining strategies for accommodating future needs. Further sustainable mobility in Slovak cities, their competitiveness, economy as well as living conditions of inhabitants are depend also on the way of Transport planning, development of Transport infrastructure and services. Generally the calculation of the interzonal Transport relations (number of trips) is a challenge. The practical application of the Transport forecast theory is not easy. Some steps are hardly implemented to the practice for various reasons. The discrepancy between needed Data and available Data is one of the common problem. The traffic modelers must often study the method of Data gathering which use an institutions possessing of demanded Data. The discrepancies are showed on different levels (for examples the borders of urban zone and statistic area units are different in principle). One of the problematic issue is the definition of work trips or business trips. The origin and destination is defined at office address. The mobility survey contains Data characterized one household, people not admit usual mentioned trips. The official company address are different as Transport department. The ratio of these trips in traffic flow is not negligible. The article is aimed to brief description of the Transport forecast process calculation. The main part of the article describes outputs from mobility surveys of some regions of Slovakia and them implementation in Transport forecast calculation process. This methodically tool is intended for traffic analysis, planned solutions and arrangements verification of problem situations solutions. The University of Žilina processed several mobility surveys. The sample covers different regions with different gravity areas. The Database was detailed evaluated and compared. Two Slovak regions were modeled in the Visum software (PTV Vision). Output Data were used for town Transport plans. Other mobility surveys were made for analysis of interstate Transport relations (Slovak republic - Hungary).
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Implementation of Transport Data in to the Transport Forecasting in Slovakia
Transportation Research Procedia, 2016Co-Authors: Marek Drličiak, Jan CelkoAbstract:The Transport forecast is the unconditional part of every Transport studies, level of service (LOS) capacity calculations or town Transport plans. It is processed for several time horizons or time intervals. The basic purpose of Transportation planning and management is to match Transportation supply with travel demand, which represents ‘need’. A thorough understanding of existing travel pattern is necessary for identifying and analyzing existing traffic related problems. Detailed Data on current travel pattern and traffic volumes are needed also for developing travel forecasting/prediction models. The prediction of future travel demand is an essential task of the long-range Transportation planning process for determining strategies for accommodating future needs. Further sustainable mobility in Slovak cities, their competitiveness, economy as well as living conditions of inhabitants are depend also on the way of Transport planning, development of Transport infrastructure and services. Generally the calculation of the interzonal Transport relations (number of trips) is a challenge. The practical application of the Transport forecast theory is not easy. Some steps are hardly implemented to the practice for various reasons. The discrepancy between needed Data and available Data is one of the common problem. The traffic modelers must often study the method of Data gathering which use an institutions possessing of demanded Data. The discrepancies are showed on different levels (for examples the borders of urban zone and statistic area units are different in principle). One of the problematic issue is the definition of work trips or business trips. The origin and destination is defined at office address. The mobility survey contains Data characterized one household, people not admit usual mentioned trips. The official company address are different as Transport department. The ratio of these trips in traffic flow is not negligible. The article is aimed to brief description of the Transport forecast process calculation. The main part of the article describes outputs from mobility surveys of some regions of Slovakia and them implementation in Transport forecast calculation process. This methodically tool is intended for traffic analysis, planned solutions and arrangements verification of problem situations solutions. The University of Žilina processed several mobility surveys. The sample covers different regions with different gravity areas. The Database was detailed evaluated and compared. Two Slovak regions were modeled in the Visum software (PTV Vision). Output Data were used for town Transport plans. Other mobility surveys were made for analysis of interstate Transport relations (Slovak republic – Hungary).
Sasa Dujko - One of the best experts on this subject based on the ideXlab platform.
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Fluid modeling of resistive plate chambers: impact of Transport Data on development of streamers and induced signals
Journal of Physics D: Applied Physics, 2016Co-Authors: D Bošnjaković, Z. Lj. Petrović, Sasa DujkoAbstract:We discuss the implementation of Transport Data in modeling of resistive plate chambers (RPCs), which are used for timing and triggering purposes in many high energy physics experiments. Particularly, we stress the importance of making a distinction between flux and bulk Transport Data when non-conservative collisions, such as attachment and/or ionization, are present. A 1.5-dimensional fluid model with photoionization is employed to demonstrate how the duality of Transport Data affects the calculated signals of the ATLAS triggering RPC and ALICE timing RPC used at CERN, and also a timing RPC with high content. It is shown that in the case of timing RPCs, the difference between the induced charges calculated using flux and bulk Transport Data can reach several hundred percent at lower operating electric fields. The effects of photoionization and space charge are also discussed.
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High order fluid model for streamer discharges: I. Derivation of model and Transport Data
Journal of Physics D: Applied Physics, 2013Co-Authors: Sasa Dujko, Ronald D. White, Aram Markosyan, Ute EbertAbstract:Streamer discharges pose basic problems in plasma physics, as they are very transient, far from equilibrium and have high ionization density gradients; they appear in diverse areas of science and technology. The present paper focuses on the derivation of a high order fluid model for streamers. Using momentum transfer theory, the fluid equations are obtained as velocity moments of the Boltzmann equation; they are closed in the local mean energy approximation and coupled to the Poisson equation for the space charge generated electric field. The high order tensor in the energy flux equation is approximated by the product of two lower order moments to close the system. The average collision frequencies for momentum and energy transfer in elastic and inelastic collisions for electrons in molecular nitrogen are calculated from a multi term Boltzmann equation solution. We then discuss, in particular, (1) the correct implementation of Transport Data in streamer models; (2) the accuracy of the two term approximation for solving Boltzmann's equation in the context of streamer studies; and (3) the evaluation of the mean-energy-dependent collision rates for electrons required as an input in the high order fluid model. In the second paper in this sequence, we will discuss the solutions of the high order fluid model for streamers, based on model and input Data derived in the present paper.
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Electron Transport Data in N2-O2 streamer plasma discharges
2010Co-Authors: Sasa Dujko, Ute Ebert, Ronald D. White, Zoran Lj. PetrovićAbstract:A multi-term theory for solving the Boltzmann equation and a Monte Carlo simulation technique are used to investigate the electron Transport in mixtures of molecular nitrogen and oxygen. We investigate the way in which the Transport coefficients and spatially resolved Transport Data are influenced by the amount of O2 in the mixture. This study was initiated in order to obtain the Transport Data for input into the fluid models and fluid components of hybrid models of streamers and has resulted in a Database of such Transport Data.
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Electron and positron swarms: Collision and Transport Data and kinetic phenomena
2008Co-Authors: Zoran Lj. Petrović, Sasa Dujko, Ana Bankovic, Jasmina Jovanovic, O. Šašić, Z. Nikitovic, Vladimir Stojanovic, Joan P MarlerAbstract:A broad review of electron swarm studies completed recently is presented with a common thread of both being motivated by major applications which use swarm physics as part of their phenomenological foundation and also with a strong presence of nonconservative (electron number changing) collisions. The review is mainly based on the activities of Gaseous Electronics Laboratory Belgrade and it cannot cover all recent and ongoing activities in swarm physics but it attempts to cover the majority of topics covered by swarm physicists in general. Thus we start with recent determinations of the cross sections from the Transport Data and calculations of the Transport Data from the cross sections from other sources in gases such as NO, N2O and mixtures of Ar and N2. We proceed to show how the presence of radicals affects the Transport coefficients in CF4, a gas with great potential for applications. The basic features of the Transport are discussed for dc and rf electric and magnetic fields. In those two chapters we mainly focus on kinetic phenomena such as negative absolute mobility, non-conservative effects in particle Transport and how angle between magnetic and electric field affects the Transport coefficients. We also discuss application of semi empirical formulas. Finally we analyze positron Transport and its difference from the Transport of electrons. The Positronium formation cross section is significantly larger than that for analogous electron nonconservative processes (i.e. electron attachment). Thus Transport of positrons gives a much stronger nonconservative effects including a new effect of the negative differential conductivity (NDC) in the bulk (WB - velocity of the center of the swarm that is relevant for the real space diffusion equation) drift velocity while the conditions required for NDC do not exist for the flux drift velocity (wF - mean velocity of particles in the swarm that is relevant for the calculations of flux when using continuity relation).
Thierry Lavé - One of the best experts on this subject based on the ideXlab platform.
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Prediction of pharmacokinetic profile of valsartan in human based on in vitro uptake Transport Data.
Journal of pharmacokinetics and pharmacodynamics, 2009Co-Authors: Agnès Poirier, Anne-christine Cascais, Christoph Funk, Thierry LavéAbstract:The aim of this study was to evaluate a strategy based on a physiologically based pharmacokinetic (PBPK) model for the prediction of PK profiles in human using in vitro Data when elimination of compounds relies on active Transport processes. The strategy was first applied to rat in vivo and in vitro Data in order to refine the PBPK model. The model could then be applied to human in vitro uptake Transport Data using valsartan as a probe substrate. Plated rat and human hepatocytes, and cell lines overexpressing human OATP1B1 and OATP1B3 were used for in vitro uptake experiments. The uptake rate of valsartan was higher for rat hepatocytes (K (m,u) = 28.4 +/- 3.7 muM, V (max) = 1318 +/- 176 pmol/mg/min and P (dif) = 1.21 +/- 0.42 microl/mg/min) compared to human hepatocytes (K (m,u) = 44.4 +/- 14.6 microM, V (max) = 304 +/- 85 pmol/mg/min and P (dif) = 0.724 +/- 0.271 microl/mg/min). OATP1B1 and 1B3 parameters were correlated to human hepatocyte Data using experimentally established relative activity factors (RAF). Resulting PBPK simulations using those in vitro Data were compared for plasma (human and rat) and bile (rat) concentration-time profiles following i.v. bolus administration of valsartan. An uncertainty analysis indicated that the scaled in vitro uptake clearance had to be adjusted with an additional empirical scaling factor of 5 to match the plasma concentrations and biliary excretion profiles. Applying this model, plasma clearances (CL(P)) for rat and human were predicted within two-fold relative to predictions based on respective in vitro Data. The corrected hepatic uptake Transport kinetic parameters enabled the prediction of valsartan in vivo PK profiles and plasma clearances, using PBPK modeling. Moreover, the interspecies difference in elimination rate observed in vivo was correctly reflected in the Transport parameters determined in vitro. More Data are needed to support more general applications of the proposed approach including its use for metabolized compounds.
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Prediction of Pharmacokinetic Profile of Valsartan in Humans Based on in vitro Uptake-Transport Data
Chemistry & biodiversity, 2009Co-Authors: Agnès Poirier, Anne-christine Cascais, Christoph Funk, Thierry LavéAbstract:The aim of this study was to evaluate a strategy based on a physiologically based pharmacokinetic (PBPK) model for the prediction of PK profiles in human using in vitro Data when elimination of compounds relies on active Transport processes. The strategy was first applied to rat in vivo and in vitro Data in order to refine the PBPK model. The model could then be applied to human in vitro uptake Transport Data using valsartan as a probe substrate. Plated rat and human hepatocytes, and cell lines overexpressing human OATP1B1 and OATP1B3 were used for in vitro uptake experiments. The uptake rate of valsartan was higher for rat hepatocytes (Km,u = 28.4 ± 3.7 μM, Vmax = 1318 ± 176 pmol/mg/min and Pdif = 1.21 ± 0.42 μl/mg/min) compared to human hepatocytes (Km,u = 44.4 ± 14.6 μM, Vmax = 304 ± 85 pmol/mg/min and Pdif = 0.724 ± 0.271 μl/mg/min). OATP1B1 and 1B3 parameters were correlated to human hepatocyte Data using experimentally established relative activity factors (RAF). Resulting PBPK simulations using those in vitro Data were compared for plasma (human and rat) and bile (rat) concentration–time profiles following i.v. bolus administration of valsartan. An uncertainty analysis indicated that the scaled in vitro uptake clearance had to be adjusted with an additional empirical scaling factor of 5 to match the plasma concentrations and biliary excretion profiles. Applying this model, plasma clearances (CLP) for rat and human were predicted within two-fold relative to predictions based on respective in vitro Data. The corrected hepatic uptake Transport kinetic parameters enabled the prediction of valsartan in vivo PK profiles and plasma clearances, using PBPK modeling. Moreover, the interspecies difference in elimination rate observed in vivo was correctly reflected in the Transport parameters determined in vitro. More Data are needed to support more general applications of the proposed approach including its use for metabolized compounds.
