WorldWideScience

Sample records for air ingress scenarios

  1. MiniPanda - a small-scale containment test facility with novel instrumentation is used for code validation for an air ingress scenario

    International Nuclear Information System (INIS)

    “MiniPanda”, a small-scale containment test facility built at ETH Zurich, was equipped with novel field measurement techniques. The capabilities of the facility were demonstrated in a first test series on an air ingress scenario. The ingress of air into a helium cooled reactor is considered to be one of the most severe accidents for the GenIV-type helium cooled reactor. The air once arrived inside the reactor can cause the oxidation of the graphite structures. The ingress of air into a helium environment was investigated experimentally and analytically using the commercial CFX-13 and StarCCM+ 5.06 CFD codes. The experimental volume consists of two cylindrical vessels that are filled separately with air or helium. The experiment is initiated by removing the blockage from the pipe connecting the two vessels. The experimental and analytical results of the consequent buoyancy-driven air ingress are compared against each other. (author)

  2. Small Break Air Ingress Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Chang Oh; Eung Soo Kim

    2011-09-01

    The small break air-ingress experiment, described in this report, is designed to investigate air-ingress phenomena postulated to occur in pipes in a very high temperature gas-cooled reactor (VHTRs). During this experiment, air-ingress rates were measured for various flow and break conditions through small holes drilled into a pipe of the experimental apparatus. The holes were drilled at right angles to the pipe wall such that a direction vector drawn from the pipe centerline to the center of each hole was at right angles with respect to the pipe centerline. Thus the orientation of each hole was obtained by measuring the included angle between the direction vector of each hole with respect to a reference line anchored on the pipe centerline and pointing in the direction of the gravitational force. Using this reference system, the influence of several important parameters on the air ingress flow rate were measured including break orientation, break size, and flow velocity . The approach used to study the influence of these parameters on air ingress is based on measuring the changes in oxygen concentrations at various locations in the helium flow circulation system as a function of time using oxygen sensors (or detectors) to estimate the air-ingress rates through the holes. The test-section is constructed of a stainless steel pipe which had small holes drilled at the desired locations.

  3. Isothermal air ingress validation experiments

    International Nuclear Information System (INIS)

    Idaho National Laboratory carried out air ingress experiments as part of validating computational fluid dynamics (CFD) calculations. An isothermal test loop was designed and set to understand the stratified-flow phenomenon, which is important as the initial air flow into the lower plenum of the very high temperature gas cooled reactor (VHTR) when a large break loss-of-coolant accident occurs. The unique flow characteristics were focused on the VHTR air-ingress accident, in particular, the flow visualization of the stratified flow in the inlet pipe to the vessel lower plenum of the General Atomic's Gas Turbine-Modular Helium Reactor (GT-MHR). Brine and sucrose were used as heavy fluids, and water was used to represent a light fluid, which mimics a counter current flow due to the density difference between the stimulant fluids. The density ratios were changed between 0.87 and 0.98. This experiment clearly showed that a stratified flow between simulant fluids was established even for very small density differences. The CFD calculations were compared with experimental data. A grid sensitivity study on CFD models was also performed using the Richardson extrapolation and the grid convergence index method for the numerical accuracy of CFD calculations . As a result, the calculated current speed showed very good agreement with the experimental data, indicating that the current CFD methods are suitable for predicting density gradient stratified flow phenomena in the air-ingress accident. (author)

  4. ISOTHERMAL AIR INGRESS VALIDATION EXPERIMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Chang H Oh; Eung S Kim

    2011-09-01

    Idaho National Laboratory carried out air ingress experiments as part of validating computational fluid dynamics (CFD) calculations. An isothermal test loop was designed and set to understand the stratified-flow phenomenon, which is important as the initial air flow into the lower plenum of the very high temperature gas cooled reactor (VHTR) when a large break loss-of-coolant accident occurs. The unique flow characteristics were focused on the VHTR air-ingress accident, in particular, the flow visualization of the stratified flow in the inlet pipe to the vessel lower plenum of the General Atomic’s Gas Turbine-Modular Helium Reactor (GT-MHR). Brine and sucrose were used as heavy fluids, and water was used to represent a light fluid, which mimics a counter current flow due to the density difference between the stimulant fluids. The density ratios were changed between 0.87 and 0.98. This experiment clearly showed that a stratified flow between simulant fluids was established even for very small density differences. The CFD calculations were compared with experimental data. A grid sensitivity study on CFD models was also performed using the Richardson extrapolation and the grid convergence index method for the numerical accuracy of CFD calculations . As a result, the calculated current speed showed very good agreement with the experimental data, indicating that the current CFD methods are suitable for predicting density gradient stratified flow phenomena in the air-ingress accident.

  5. AIR INGRESS ANALYSIS: COMPUTATIONAL FLUID DYNAMIC MODELS

    International Nuclear Information System (INIS)

    The Idaho National Laboratory (INL), under the auspices of the U.S. Department of Energy, is performing research and development that focuses on key phenomena important during potential scenarios that may occur in very high temperature reactors (VHTRs). Phenomena Identification and Ranking Studies to date have ranked an air ingress event, following on the heels of a VHTR depressurization, as important with regard to core safety. Consequently, the development of advanced air ingress-related models and verification and validation data are a very high priority. Following a loss of coolant and system depressurization incident, air will enter the core of the High Temperature Gas Cooled Reactor through the break, possibly causing oxidation of the in-the core and reflector graphite structure. Simple core and plant models indicate that, under certain circumstances, the oxidation may proceed at an elevated rate with additional heat generated from the oxidation reaction itself. Under postulated conditions of fluid flow and temperature, excessive degradation of the lower plenum graphite can lead to a loss of structural support. Excessive oxidation of core graphite can also lead to the release of fission products into the confinement, which could be detrimental to a reactor safety. Computational fluid dynamic model developed in this study will improve our understanding of this phenomenon. This paper presents two-dimensional and three-dimensional CFD results for the quantitative assessment of the air ingress phenomena. A portion of results of the density-driven stratified flow in the inlet pipe will be compared with results of the experimental results.

  6. AIR INGRESS ANALYSIS: COMPUTATIONAL FLUID DYNAMIC MODELS

    Energy Technology Data Exchange (ETDEWEB)

    Chang H. Oh; Eung S. Kim; Richard Schultz; Hans Gougar; David Petti; Hyung S. Kang

    2010-08-01

    The Idaho National Laboratory (INL), under the auspices of the U.S. Department of Energy, is performing research and development that focuses on key phenomena important during potential scenarios that may occur in very high temperature reactors (VHTRs). Phenomena Identification and Ranking Studies to date have ranked an air ingress event, following on the heels of a VHTR depressurization, as important with regard to core safety. Consequently, the development of advanced air ingress-related models and verification and validation data are a very high priority. Following a loss of coolant and system depressurization incident, air will enter the core of the High Temperature Gas Cooled Reactor through the break, possibly causing oxidation of the in-the core and reflector graphite structure. Simple core and plant models indicate that, under certain circumstances, the oxidation may proceed at an elevated rate with additional heat generated from the oxidation reaction itself. Under postulated conditions of fluid flow and temperature, excessive degradation of the lower plenum graphite can lead to a loss of structural support. Excessive oxidation of core graphite can also lead to the release of fission products into the confinement, which could be detrimental to a reactor safety. Computational fluid dynamic model developed in this study will improve our understanding of this phenomenon. This paper presents two-dimensional and three-dimensional CFD results for the quantitative assessment of the air ingress phenomena. A portion of results of the density-driven stratified flow in the inlet pipe will be compared with results of the experimental results.

  7. CFD Analyses of Air-Ingress Accident for VHTRs

    Science.gov (United States)

    Ham, Tae Kyu

    The Very High Temperature Reactor (VHTR) is one of six proposed Generation-IV concepts for the next generation of nuclear powered plants. The VHTR is advantageous because it is able to operate at very high temperatures, thus producing highly efficient electrical generation and hydrogen production. A critical safety event of the VHTR is a loss-of-coolant accident. This accident is initiated, in its worst-case scenario, by a double-ended guillotine break of the cross vessel that connects the reactor vessel and the power conversion unit. Following the depressurization process, the air (i.e., the air and helium mixture) in the reactor cavity could enter the reactor core causing an air-ingress event. In the event of air-ingress into the reactor core, the high-temperature in-core graphite structures will chemically react with the air and could lose their structural integrity. We designed a 1/8th scaled-down test facility to develop an experimental database for studying the mechanisms involved in the air-ingress phenomenon. The current research focuses on the analysis of the air-ingress phenomenon using the computational fluid dynamics (CFD) tool ANSYS FLUENT for better understanding of the air-ingress phenomenon. The anticipated key steps in the air-ingress scenario for guillotine break of VHTR cross vessel are: 1) depressurization; 2) density-driven stratified flow; 3) local hot plenum natural circulation; 4) diffusion into the reactor core; and 5) global natural circulation. However, the OSU air-ingress test facility covers the time from depressurization to local hot plenum natural circulation. Prior to beginning the CFD simulations for the OSU air-ingress test facility, benchmark studies for the mechanisms which are related to the air-ingress accident, were performed to decide the appropriate physical models for the accident analysis. In addition, preliminary experiments were performed with a simplified 1/30th scaled down acrylic set-up to understand the air-ingress

  8. Air ingress benchmarking with computational fluid dynamics analysis

    International Nuclear Information System (INIS)

    The air ingress accident is a complicated accident scenario that may limit the deployment of high-temperature gas reactors. The complexity of this accident scenario is compounded by multiple physical phenomena that are involved in the air ingress event. These include diffusion, natural circulation, and complex chemical reactions with graphite and oxygen. In an attempt to better understand the phenomenon, the FLUENT-6 computational fluid dynamics code was used to assess two air ingress experiments. The first was the Japanese series of tests performed in the early 1990s by Takeda and Hishida. These separate effects tests were conducted to understand and model a multi-component experiment in which all three processes were included with the introduction of air in a heated graphite column. MIT used the FLUENT code to benchmark these series of tests with quite good results. These tests are generically applicable to prismatic reactors and the lower reflector regions of pebble-bed reactors. The second series of tests were performed at the NACOK facility for pebble bed reactors as reported by Kuhlmann [Kuhlmann, M.B., 1999. Experiments to investigate flow transfer and graphite corrosion in case of air ingress accidents in a high-temperature reactor]. These tests were aimed at understanding natural circulation of pebble bed reactors by simulating hot and cold legs of these reactors. The FLUENT code was also successfully used to simulate these tests. The results of these benchmarks and the findings will be presented

  9. Phenomenology of Graphite Burning in Air Ingress Accidents of HTRs

    International Nuclear Information System (INIS)

    Air ingress with graphite burning belongs to the accident scenarios in HTRs with potentially severe consequences. This paper gives an overview of basic phenomena of graphite burning like ignition conditions and moving reaction fronts. The pioneering graphite burning experiments of Don Schweitzer are successfully reevaluated. Ignition conditions are examined, and it is underlined that burning depends not only on graphite properties but also on the heat balance in the whole graphite arrangement. In graphite-moderated reactors, ignition occurs at about 650 degree C for small air flow rates: this means that normal operation temperatures in HTRs always allow for ignition. Fuel behaviour in air ingress, as determined in the KORA facility, is discussed: up to about 1300 degree C modern TRISO fuel is stable in air, but from 1500 degree C a complete, fast destruction is observed. Exemplary calculations on massive air ingress by chimney draught performed with REACT/THERMIX are outlined. For a hot bottom reflector there is a substantial time span before fuel is attacked. Because severe air ingress in well-designed HTRs belongs to beyond design basis accidents, the knowledge is fairly good. Concerning protecting measures, a more detailed examination of thick SiC layers is proposed.

  10. Study of air ingress accident of an HTGR

    International Nuclear Information System (INIS)

    Inherent properties of high temperature gas cooled reactors (HTGR) facilitate the design of HTGRs with high degree of passive safety performances. In this context, it is very important to establish a design criteria for a passive safe function for the air ingress accident. However, it is absolutely necessary to investigate the air ingress behavior during the accident before exploring the design criteria. The present paper briefly describes major activities and results of the air ingress research in our laboratory. (author)

  11. Analysis on the Density Driven Air-Ingress Accident in VHTRs

    International Nuclear Information System (INIS)

    Air-ingress following the pipe rupture is considered to be the most serious accident in the VHTRs due to its potential problems such as core heat-up, structural integrity and toxic gas release. Previously, it has been believed that the main air-ingress mechanism of this accident is the molecular diffusion process between the reactor core and the cavity. However, according to some recent studies, there is another fast air-ingress process that has not been considered before. It is called density-driven stratified flow. The potential for density-driven stratified air ingress into the VHTR following a large-break LOCA was first described in the NGNP Methods Technical Program based on stratified flow studies performed with liquid. Studies on densitygradient driven stratified flow in advanced reactor systems has been the subject of active research for well over a decade since density-gradient dominated stratified flow is an inherent characteristic of passive systems used in advanced reactors. Recently, Oh et al. performed a CFD analysis on the stratified flow in the VHTR, and showed that this effect can significantly accelerate the air-ingress process in the VHTRs. They also proposed to replace the original air-ingress scenario based on the molecular diffusion with the one based on the stratified flow. This paper is focusing on the effect of stratified flow on the results of the air-ingress accident in VHTR

  12. Air-ingress analysis: Part 1. Theoretical approach

    International Nuclear Information System (INIS)

    Idaho National Laboratory (INL), under the auspices of the U.S. Department of Energy (DOE), is performing research and development that focuses on key phenomena important during potential scenarios that may occur in very high temperature gas-cooled reactors (VHTRs). Phenomena identification and ranking studies to date have ranked an air-ingress event, following on the heels of a VHTR depressurization, as important with regard to core safety. Consequently, the development of advanced air-ingress-related models and verification and validation data are a very high priority. Following a loss of coolant and system depressurization incident, air will enter the core of the VHTR through the break, possibly causing oxidation of the graphite core and reflector graphite structure. Simple core and plant models indicate that, under certain circumstances, the oxidation may proceed at an elevated rate with additional heat generated from the oxidation reaction itself. Under postulated conditions of fluid flow and temperature, excessive degradation of lower plenum graphite caused by graphite oxidation can lead to a loss of mechanical strength. Excessive oxidation of core graphite can also lead to a release of fission products into the confinement, which could be detrimental to reactor safety. Analytical models developed in this study will improve our understanding of this phenomenon. This paper presents two sets of analytical models for the qualitative assessment of the air-ingress phenomena. The results from the analytical models are compared with results of the computational fluid dynamic models (CFD) in the subsequent paper. The analytical models agree well with those CFD results.

  13. Study of Air Ingress Across the Duct During the Accident Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, Yassin [Texas A & M Univ., College Station, TX (United States)

    2013-05-06

    The goal of this project is to study the fundamental physical phenomena associated with air ingress in very high temperature reactors (VHTRs). Air ingress may occur due to a rupture of primary piping and a subsequent breach in the primary pressure boundary in helium-cooled and graphite-moderated VHTRs. Significant air ingress is a concern because it introduces potential to expose the fuel, graphite support rods, and core to a risk of severe graphite oxidation. Two of the most probable air ingress scenarios involve rupture of a control rod or fuel access standpipe, and rupture in the main coolant pipe on the lower part of the reactor pressure vessel. Therefore, establishing a fundamental understanding of air ingress phenomena is critical in order to rationally evaluate safety of existing VHTRs and develop new designs that minimize these risks. But despite this importance, progress toward development these predictive capabilities has been slowed by the complex nature of the underlying phenomena. The combination of inter-diffusion among multiple species, molecular diffusion, natural convection, and complex geometries, as well as the multiple chemical reactions involved, impose significant roadblocks to both modeling and experiment design. The project team will employ a coordinated experimental and computational effort that will help gain a deeper understanding of multiphased air ingress phenomena. This project will enhance advanced modeling and simulation methods, enabling calculation of nuclear power plant transients and accident scenarios with a high degree of confidence. The following are the project tasks: Perform particle image velocimetry measurement of multiphase air ingresses; and, Perform computational fluid dynamics analysis of air ingress phenomena.

  14. Study of Air Ingress Across the Duct During the Accident Conditions

    International Nuclear Information System (INIS)

    The goal of this project is to study the fundamental physical phenomena associated with air ingress in very high temperature reactors (VHTRs). Air ingress may occur due to a rupture of primary piping and a subsequent breach in the primary pressure boundary in helium-cooled and graphite-moderated VHTRs. Significant air ingress is a concern because it introduces potential to expose the fuel, graphite support rods, and core to a risk of severe graphite oxidation. Two of the most probable air ingress scenarios involve rupture of a control rod or fuel access standpipe, and rupture in the main coolant pipe on the lower part of the reactor pressure vessel. Therefore, establishing a fundamental understanding of air ingress phenomena is critical in order to rationally evaluate safety of existing VHTRs and develop new designs that minimize these risks. But despite this importance, progress toward development these predictive capabilities has been slowed by the complex nature of the underlying phenomena. The combination of inter-diffusion among multiple species, molecular diffusion, natural convection, and complex geometries, as well as the multiple chemical reactions involved, impose significant roadblocks to both modeling and experiment design. The project team will employ a coordinated experimental and computational effort that will help gain a deeper understanding of multiphased air ingress phenomena. This project will enhance advanced modeling and simulation methods, enabling calculation of nuclear power plant transients and accident scenarios with a high degree of confidence. The following are the project tasks: Perform particle image velocimetry measurement of multiphase air ingresses; and, Perform computational fluid dynamics analysis of air ingress phenomena.

  15. Progress in air ingress simulation with ATHLET-CD

    International Nuclear Information System (INIS)

    To ensure the coolability of an overheated core, reflood of the uncovered fuel elements is an essential accident management measure to terminate a severe accident transient in Light Water Reactors (LWR) and therefore to avoid further core degradation. From analysis of the TMI-2 accident it is known that an enhanced oxidation of the Zircaloy cladding may occur before the water succeeds in cooling the fuel rods. This oxidation process results in a sharp temperature increase, hydrogen generation and can finally after fuel rod cladding failure lead to fission product release. For further development and validation of the program ATHLET-CD (Analysis of Thermal-hydraulics of Leaks and Transients - Core Degradation), post-test calculations of experiments creating a reflood scenario in a controlled and defined environment are used. One of these experiments is QUNECH-16 in which air is injected into the bundle region to simulate air ingress. Through the oxidation in air atmosphere the core degradation continues and speeds up due to the more exothermic reactions. In this work, the QUENCH-16 experiment and its conduct will be presented followed by explanations of the modelling in ATHLET-CD version 2.2A, and version 2.2C respectively. The main difference is the ability of version 2.2C to consider nitride formation under oxygen starved conditions during the oxidation process. Results of both ATHLET-CD versions simulating the test will be discussed in order to validate the code's ability to adequately calculate phenomena like hydrogen production and oxidation behaviour during an air ingress scenario. (orig.)

  16. Progress in air ingress simulation with ATHLET-CD

    Energy Technology Data Exchange (ETDEWEB)

    Bratfisch, Christian; Hoffmann, Mathias; Koch, Marco K. [Bochum Univ. (Germany). Reactor Simulation and Safety Group

    2013-07-01

    To ensure the coolability of an overheated core, reflood of the uncovered fuel elements is an essential accident management measure to terminate a severe accident transient in Light Water Reactors (LWR) and therefore to avoid further core degradation. From analysis of the TMI-2 accident it is known that an enhanced oxidation of the Zircaloy cladding may occur before the water succeeds in cooling the fuel rods. This oxidation process results in a sharp temperature increase, hydrogen generation and can finally after fuel rod cladding failure lead to fission product release. For further development and validation of the program ATHLET-CD (Analysis of Thermal-hydraulics of Leaks and Transients - Core Degradation), post-test calculations of experiments creating a reflood scenario in a controlled and defined environment are used. One of these experiments is QUNECH-16 in which air is injected into the bundle region to simulate air ingress. Through the oxidation in air atmosphere the core degradation continues and speeds up due to the more exothermic reactions. In this work, the QUENCH-16 experiment and its conduct will be presented followed by explanations of the modelling in ATHLET-CD version 2.2A, and version 2.2C respectively. The main difference is the ability of version 2.2C to consider nitride formation under oxygen starved conditions during the oxidation process. Results of both ATHLET-CD versions simulating the test will be discussed in order to validate the code's ability to adequately calculate phenomena like hydrogen production and oxidation behaviour during an air ingress scenario. (orig.)

  17. CFD analysis of air ingress distribution during mid-loop accident sequences

    International Nuclear Information System (INIS)

    The accident management approach affects nuclear technology and safety with a new formulation of basic hypotheses for the evaluation of the Source Term and radiological impact on the population due to Fission Product release following Severe Accidents. Considering also the wide spectrum of hypothetical and low probability accident scenarios having these kind of consequences, the sequences having potential for air ingress into the reactor coolant system or involving the interaction between fuel and air, which can flow into the reactor coolant system from the containment, have recently gained more and more interest. The research activities summarised in this paper have been carried out at the Department of Mechanical, Nuclear and Production Engineering of Pisa University, in the frame of an international Project of the IV European Community Framework Programme. The activity included a review of the spectrum of accident sequences to be considered for the investigation of the air ingress probability, the behaviour and the effects of air ingress into the reactor core. Two classes of scenarios were identified for a more in-depth analysis: (a) mid-loop sequences, and (b) scenarios including vessel melt-through. In this frame, mid-loop sequences, having more probabilistic interest than vessel melt-through scenarios, have been investigated by using 3D analytical tools (i.e. Fluent V5.0 fluid-dynamic code). (author)

  18. STUDY ON AIR INGRESS MITIGATION METHODS IN THE VERY HIGH TEMPERATURE GAS COOLED REACTOR (VHTR)

    Energy Technology Data Exchange (ETDEWEB)

    Chang H. Oh

    2011-03-01

    An air-ingress accident followed by a pipe break is considered as a critical event for a very high temperature gas-cooled reactor (VHTR). Following helium depressurization, it is anticipated that unless countermeasures are taken, air will enter the core through the break leading to oxidation of the in-core graphite structure. Thus, without mitigation features, this accident might lead to severe exothermic chemical reactions of graphite and oxygen. Under extreme circumstances, a loss of core structural integrity may occur along with excessive release of radiological inventory. Idaho National Laboratory under the auspices of the U.S. Department of Energy is performing research and development (R&D) that focuses on key phenomena important during challenging scenarios that may occur in the VHTR. Phenomena Identification and Ranking Table (PIRT) studies to date have identified the air ingress event, following on the heels of a VHTR depressurization, as very important (Oh et al. 2006, Schultz et al. 2006). Consequently, the development of advanced air ingress-related models and verification and validation (V&V) requirements are part of the experimental validation plan. This paper discusses about various air-ingress mitigation concepts applicable for the VHTRs. The study begins with identifying important factors (or phenomena) associated with the air-ingress accident by using a root-cause analysis. By preventing main causes of the important events identified in the root-cause diagram, the basic air-ingress mitigation ideas can be conceptually derived. The main concepts include (1) preventing structural degradation of graphite supporters; (2) preventing local stress concentration in the supporter; (3) preventing graphite oxidation; (4) preventing air ingress; (5) preventing density gradient driven flow; (4) preventing fluid density gradient; (5) preventing fluid temperature gradient; (6) preventing high temperature. Based on the basic concepts listed above, various air-ingress

  19. Experimental Validation of Stratified Flow Phenomena, Graphite Oxidation, and Mitigation Strategies of Air Ingress Accidents

    Energy Technology Data Exchange (ETDEWEB)

    Chang Ho Oh; Eung Soo Kim; Hee Cheon No; Nam Zin Cho

    2008-12-01

    The US Department of Energy is performing research and development (R&D) that focuses on key phenomena that are important during challenging scenarios that may occur in the Next Generation Nuclear Plant (NGNP) Program / GEN-IV Very High Temperature Reactor (VHTR). Phenomena identification and ranking studies (PIRT) to date have identified the air ingress event, following on the heels of a VHTR depressurization, as very important (Schultz et al., 2006). Consequently, the development of advanced air ingress-related models and verification and validation (V&V) are very high priority for the NGNP program. Following a loss of coolant and system depressurization, air will enter the core through the break. Air ingress leads to oxidation of the in-core graphite structure and fuel. The oxidation will accelerate heat-up of the bottom reflector and the reactor core and will cause the release of fission products eventually. The potential collapse of the bottom reflector because of burn-off and the release of CO lead to serious safety problems. For estimation of the proper safety margin we need experimental data and tools, including accurate multi-dimensional thermal-hydraulic and reactor physics models, a burn-off model, and a fracture model. We also need to develop effective strategies to mitigate the effects of oxidation. The results from this research will provide crucial inputs to the INL NGNP/VHTR Methods R&D project. This project is focused on (a) analytical and experimental study of air ingress caused by density-driven, stratified, countercurrent flow, (b) advanced graphite oxidation experiments, (c) experimental study of burn-off in the bottom reflector, (d) structural tests of the burnt-off bottom reflector, (e) implementation of advanced models developed during the previous tasks into the GAMMA code, (f) full air ingress and oxidation mitigation analyses, (g) development of core neutronic models, (h) coupling of the core neutronic and thermal hydraulic models, and (i

  20. Autonomous Landing and Ingress of Micro-Air-Vehicles in Urban Environments Based on Monocular Vision

    Science.gov (United States)

    Brockers, Roland; Bouffard, Patrick; Ma, Jeremy; Matthies, Larry; Tomlin, Claire

    2011-01-01

    Unmanned micro air vehicles (MAVs) will play an important role in future reconnaissance and search and rescue applications. In order to conduct persistent surveillance and to conserve energy, MAVs need the ability to land, and they need the ability to enter (ingress) buildings and other structures to conduct reconnaissance. To be safe and practical under a wide range of environmental conditions, landing and ingress maneuvers must be autonomous, using real-time, onboard sensor feedback. To address these key behaviors, we present a novel method for vision-based autonomous MAV landing and ingress using a single camera for two urban scenarios: landing on an elevated surface, representative of a rooftop, and ingress through a rectangular opening, representative of a door or window. Real-world scenarios will not include special navigation markers, so we rely on tracking arbitrary scene features; however, we do currently exploit planarity of the scene. Our vision system uses a planar homography decomposition to detect navigation targets and to produce approach waypoints as inputs to the vehicle control algorithm. Scene perception, planning, and control run onboard in real-time; at present we obtain aircraft position knowledge from an external motion capture system, but we expect to replace this in the near future with a fully self-contained, onboard, vision-aided state estimation algorithm. We demonstrate autonomous vision-based landing and ingress target detection with two different quadrotor MAV platforms. To our knowledge, this is the first demonstration of onboard, vision-based autonomous landing and ingress algorithms that do not use special purpose scene markers to identify the destination.

  1. Studies on air ingress for pebble bed reactors

    International Nuclear Information System (INIS)

    A loss-of-coolant accident (LOCA) has been considered a critical event for helium-cooled pebbled bed reactors. Following helium depressurization, it is anticipated that unless countermeasures are taken air will enter the core through the break and then by molecular diffusion and ultimately by natural convection leading to oxidation of the in-core graphite structure and graphite pebbles. Thus, without any mitigating features a LOCA will lead to an air ingress event. The INEEL is studying such an event with two well-respected light water reactor transient response codes: RELAP5/ATHENA and MELCOR. To study the degree of graphite oxidation occurring due to an air ingress event, a MELCOR model of a reference pebble bed design was constructed. A modified version of MELCOR developed at INEEL, which includes graphite oxidation capabilities, and molecular diffusion of air into helium was used for these calculations. Results show that the lower reflector graphite consumes all of the oxygen before reaching the core. The results also show a long time delay between the time that the depressurization phase of the accident is over and the time that natural circulation air through the core occurs. (author)

  2. Implications of Air Ingress Induced by Density-Difference Driven Stratified Flow

    International Nuclear Information System (INIS)

    One of the design basis accidents for the Next Generation Nuclear Plant (NGNP), a high temperature gas-cooled reactor, is air ingress subsequent to a pipe break. Following a postulated double-ended guillotine break in the hot duct, and the subsequent depressurization to nearly reactor cavity pressure levels, air present in the reactor cavity will enter the reactor vessel via density-gradient-driven-stratified flow. Because of the significantly higher molecular weight and lower initial temperature of the reactor cavity air-helium mixture, in contrast to the helium in the reactor vessel, the air-helium mixture in the cavity always has a larger density than the helium discharging from the reactor vessel through the break into the reactor cavity. In the later stages of the helium blowdown, the momentum of the helium flow decreases sufficiently for the heavier cavity air-helium mixture to intrude into the reactor vessel lower plenum through the lower portion of the break. Once it has entered, the heavier gas will pool at the bottom of the lower plenum. From there it will move upwards into the core via diffusion and density-gradient effects that stem from heating the air-helium mixture and from the pressure differences between the reactor cavity and the reactor vessel. This scenario (considering density-gradient-driven stratified flow) is considerably different from the heretofore commonly used scenario that attributes movement of air into the reactor vessel and from thence to the core region via diffusion. When density-gradient-driven stratified flow is considered as a contributing phenomena for air ingress into the reactor vessel, the following factors contribute to a much earlier natural circulation-phase in the reactor vessel: (a) density-gradient-driven stratified flow is a much more rapid mechanism (at least one order of magnitude) for moving air into the reactor vessel lower plenum than diffusion, and consequently, (b) the diffusion dominated phase begins with a

  3. Implications of Air Ingress Induced by Density-Difference Driven Stratified Flow

    Energy Technology Data Exchange (ETDEWEB)

    Chang Oh; Eung Soo Kim; Richard Schultz; David Petti; C. P. Liou

    2008-06-01

    One of the design basis accidents for the Next Generation Nuclear Plant (NGNP), a high temperature gas-cooled reactor, is air ingress subsequent to a pipe break. Following a postulated double-ended guillotine break in the hot duct, and the subsequent depressurization to nearly reactor cavity pressure levels, air present in the reactor cavity will enter the reactor vessel via density-gradient-driven-stratified flow. Because of the significantly higher molecular weight and lower initial temperature of the reactor cavity air-helium mixture, in contrast to the helium in the reactor vessel, the air-helium mixture in the cavity always has a larger density than the helium discharging from the reactor vessel through the break into the reactor cavity. In the later stages of the helium blowdown, the momentum of the helium flow decreases sufficiently for the heavier cavity air-helium mixture to intrude into the reactor vessel lower plenum through the lower portion of the break. Once it has entered, the heavier gas will pool at the bottom of the lower plenum. From there it will move upwards into the core via diffusion and density-gradient effects that stem from heating the air-helium mixture and from the pressure differences between the reactor cavity and the reactor vessel. This scenario (considering density-gradient-driven stratified flow) is considerably different from the heretofore commonly used scenario that attributes movement of air into the reactor vessel and from thence to the core region via diffusion. When density-gradient-driven stratified flow is considered as a contributing phenomena for air ingress into the reactor vessel, the following factors contribute to a much earlier natural circulation-phase in the reactor vessel: (a) density-gradient-driven stratified flow is a much more rapid mechanism (at least one order of magnitude) for moving air into the reactor vessel lower plenum than diffusion, and consequently, (b) the diffusion dominated phase begins with a

  4. FINAL REPORT on Experimental Validation of Stratified Flow Phenomena, Graphite Oxidation, and Mitigation Strategies of Air Ingress Accidents

    Energy Technology Data Exchange (ETDEWEB)

    Chang H. Oh; Eung S. Kim; Hee C. NO; Nam Z. Cho

    2011-01-01

    The U.S. Department of Energy is performing research and development that focuses on key phenomena that are important during challenging scenarios that may occur in the Next Generation Nuclear Plant (NGNP)/Generation IV very high temperature reactor (VHTR). Phenomena Identification and Ranking studies to date have identified the air ingress event, following on the heels of a VHTR depressurization, as very important. Consequently, the development of advanced air ingress-related models and verification & validation are of very high priority for the NGNP Project. Following a loss of coolant and system depressurization incident, air ingress will occur through the break, leading to oxidation of the in-core graphite structure and fuel. This study indicates that depending on the location and the size of the pipe break, the air ingress phenomena are different. In an effort to estimate the proper safety margin, experimental data and tools, including accurate multidimensional thermal-hydraulic and reactor physics models, a burn-off model, and a fracture model are required. It will also require effective strategies to mitigate the effects of oxidation, eventually. This 3-year project (FY 2008–FY 2010) is focused on various issues related to the VHTR air-ingress accident, including (a) analytical and experimental study of air ingress caused by density-driven, stratified, countercurrent flow, (b) advanced graphite oxidation experiments, (c) experimental study of burn-off in the core bottom structures, (d) structural tests of the oxidized core bottom structures, (e) implementation of advanced models developed during the previous tasks into the GAMMA code, (f) full air ingress and oxidation mitigation analyses, (g) development of core neutronic models, (h) coupling of the core neutronic and thermal hydraulic models, and (i) verification and validation of the coupled models.

  5. Investigation of Countercurrent Helium-Air Flows in Air-ingress Accidents for VHTRs

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Xiaodong; Christensen, Richard; Oh, Chang

    2013-10-03

    The primary objective of this research is to develop an extensive experimental database for the air- ingress phenomenon for the validation of computational fluid dynamics (CFD) analyses. This research is intended to be a separate-effects experimental study. However, the project team will perform a careful scaling analysis prior to designing a scaled-down test facility in order to closely tie this research with the real application. As a reference design in this study, the team will use the 600 MWth gas turbine modular helium reactor (GT-MHR) developed by General Atomic. In the test matrix of the experiments, researchers will vary the temperature and pressure of the helium— along with break size, location, shape, and orientation—to simulate deferent scenarios and to identify potential mitigation strategies. Under support of the Department of Energy, a high-temperature helium test facility has been designed and is currently being constructed at Ohio State University, primarily for high- temperature compact heat exchanger testing for the VHTR program. Once the facility is in operation (expected April 2009), this study will utilize high-temperature helium up to 900°C and 3 MPa for loss-of-coolant accident (LOCA) depressurization and air-ingress experiments. The project team will first conduct a scaling study and then design an air-ingress test facility. The major parameter to be measured in the experiments is oxygen (or nitrogen) concentration history at various locations following a LOCA scenario. The team will use two measurement techniques: 1) oxygen (or similar type) sensors employed in the flow field, which will introduce some undesirable intrusiveness, disturbing the flow, and 2) a planar laser-induced fluorescence (PLIF) imaging technique, which has no physical intrusiveness to the flow but requires a transparent window or test section that the laser beam can penetrate. The team will construct two test facilities, one for high-temperature helium tests with

  6. Results of the QUENCH-10 air ingress test using ATHLET-CD

    International Nuclear Information System (INIS)

    In case of a postulated breakdown of the main and the emergency cooling systems during a loss of cooling accident in light water reactors, severe core damage or even core degradation is possible. To avoid the total melting of the core, the uncovered and overheated core has to be cooled, i. e. by flooding with water. In the framework of the QUENCH programme at Forschungszentrum Karlsruhe (FZK) the behaviour of fuel rod bundles during reflood scenarios is investigated. A specific focus lays on the hydrogen generation due to the exothermal zirconium-steam-reaction during the quench phase, but additionally B44C oxidation as well as air ingress is investigated. Based on the post-test calculations of the QUENCH tests with the severe accident code ATHLET-CD the capability of the code can be established and evaluated. In the following the post-test calculation of the experiment QUENCH-10 with ATHLET-CD 2.1A is presented and discussed. The QUENCH-10 test was performed on the 21st of July 2004 at FZK in the framework of the EC-supported LACOMERA programme to improve the knowledge of the phenomena during an air ingress scenario with the objective to observe the oxidation and nitride formation processes and to investigate the bundle behaviour during the subsequent quenching by water. A postulated loss of heat removal in a spent fuel pool or loss of coolant accident in a reactor application could lead to the evaporation of the water in the pool and the degradation of the fuel assemblies by air ingress which could lead to fission product release from the degraded core. (orig.)

  7. Results of the QUENCH-10 air ingress test using ATHLET-CD

    Energy Technology Data Exchange (ETDEWEB)

    Hollands, Thorsten; Drath, Tilman; Wagner, Hermann-Josef; Koch, Marco K. [Bochum Univ. (RUB) (DE). Lehrstuhl fuer Energiesysteme und Energiewirtschaft (LEE)

    2008-07-01

    In case of a postulated breakdown of the main and the emergency cooling systems during a loss of cooling accident in light water reactors, severe core damage or even core degradation is possible. To avoid the total melting of the core, the uncovered and overheated core has to be cooled, i. e. by flooding with water. In the framework of the QUENCH programme at Forschungszentrum Karlsruhe (FZK) the behaviour of fuel rod bundles during reflood scenarios is investigated. A specific focus lays on the hydrogen generation due to the exothermal zirconium-steam-reaction during the quench phase, but additionally B{sub 4}4C oxidation as well as air ingress is investigated. Based on the post-test calculations of the QUENCH tests with the severe accident code ATHLET-CD the capability of the code can be established and evaluated. In the following the post-test calculation of the experiment QUENCH-10 with ATHLET-CD 2.1A is presented and discussed. The QUENCH-10 test was performed on the 21{sup st} of July 2004 at FZK in the framework of the EC-supported LACOMERA programme to improve the knowledge of the phenomena during an air ingress scenario with the objective to observe the oxidation and nitride formation processes and to investigate the bundle behaviour during the subsequent quenching by water. A postulated loss of heat removal in a spent fuel pool or loss of coolant accident in a reactor application could lead to the evaporation of the water in the pool and the degradation of the fuel assemblies by air ingress which could lead to fission product release from the degraded core. (orig.)

  8. Scaling and design analyses of a scaled-down, high-temperature test facility for experimental investigation of the initial stages of a VHTR air-ingress accident

    International Nuclear Information System (INIS)

    A critical event in the safety analysis of the very high-temperature gas-cooled reactor (VHTR) is an air-ingress accident. This accident is initiated, in its worst case scenario, by a double-ended guillotine break of the coaxial cross vessel, which leads to a rapid reactor vessel depressurization. In a VHTR, the reactor vessel is located within a reactor cavity that is filled with air during normal operating conditions. Following the vessel depressurization, the dominant mode of ingress of an air—helium mixture into the reactor vessel will either be molecular diffusion or density-driven stratified flow. The mode of ingress is hypothesized to depend largely on the break conditions of the cross vessel. Since the time scales of these two ingress phenomena differ by orders of magnitude, it is imperative to understand under which conditions each of these mechanisms will dominate in the air ingress process. Computer models have been developed to analyze this type of accident scenario. There are, however, limited experimental data available to understand the phenomenology of the air-ingress accident and to validate these models. Therefore, there is a need to design and construct a scaled-down experimental test facility to simulate the air-ingress accident scenarios and to collect experimental data. The current paper focuses on the analyses performed for the design and operation of a 1/8th geometric scale (by height and diameter), high-temperature test facility. A geometric scaling analysis for the VHTR, a time scale analysis of the air-ingress phenomenon, a transient depressurization analysis of the reactor vessel, a hydraulic similarity analysis of the test facility, a heat transfer characterization of the hot plenum, a power scaling analysis for the reactor system, and a design analysis of the containment vessel are discussed.

  9. Simulation of the air ingress experiment parameter SF4 using ATHLET-CD

    International Nuclear Information System (INIS)

    The air ingress test PARAMETER SF4 was performed in July 2009 with the aim to investigate the behavior of a VVER bundle during reflooding after air ingress. Simulations are performed using the severe accident code ATHLET-CD. The results of the simulations show a good agreement in comparison to the experimental data during the pre-oxidation phase and in most bundle regions also during air ingress. The hydrogen generation is very close to the experimental data up to the beginning of quenching; afterwards the total amount of H2 is underpredicted. Further improvement can be achieved by using a model to consider ZrN formation. (author)

  10. Validations of CFD Code for Density-Gradient Driven Air Ingress Stratified Flow

    International Nuclear Information System (INIS)

    Air ingress into a very high temperature gas-cooled reactor (VHTR) is an important phenomena to consider because the air oxidizes the reactor core and lower plenum where the graphite structure supports the core region in the gas turbine modular helium reactor (GTMHR) design, thus jeopardizing the reactor's safety. Validating the computational fluid dynamics (CFD) code used to analyze the air ingress phenomena is therefore an essential part of the safety analysis and the ultimate computation required for licensing.

  11. FY-09 Report: Experimental Validation of Stratified Flow Phenomena, Graphite Oxidation, and Mitigation Strategies of Air Ingress Accidents

    Energy Technology Data Exchange (ETDEWEB)

    Chang H. Oh; Eung S. Kim

    2009-12-01

    The Idaho National Laboratory (INL), under the auspices of the U.S. Department of Energy, is performing research and development that focuses on key phenomena important during potential scenarios that may occur in the Next Generation Nuclear Plant (NGNP)/Gen-IV very high temperature reactor (VHTR). Phenomena Identification and Ranking Studies to date have identified that an air ingress event following on the heels of a VHTR depressurization is a very important incident. Consequently, the development of advanced air ingress-related models and verification and validation data are a very high priority for the NGNP Project. Following a loss of coolant and system depressurization incident, air will enter the core through the break, leading to oxidation of the in-core graphite structure and fuel. If this accident occurs, the oxidation will accelerate heat-up of the bottom reflector and the reactor core and will eventually cause the release of fission products. The potential collapse of the core bottom structures causing the release of CO and fission products is one of the concerns. Therefore, experimental validation with the analytical model and computational fluid dynamic (CFD) model developed in this study is very important. Estimating the proper safety margin will require experimental data and tools, including accurate multidimensional thermal-hydraulic and reactor physics models, a burn-off model, and a fracture model. It will also require effective strategies to mitigate the effects of oxidation. The results from this research will provide crucial inputs to the INL NGNP/VHTR Methods Research and Development project. The second year of this three-year project (FY-08 to FY-10) was focused on (a) the analytical, CFD, and experimental study of air ingress caused by density-driven, stratified, countercurrent flow; (b) advanced graphite oxidation experiments and modeling; (c) experimental study of burn-off in the core bottom structures, (d) implementation of advanced

  12. Air ingress behavior during a primary-pipe rupture accident of HTGR

    International Nuclear Information System (INIS)

    The inherent properties of a HTGR facilitates the design with high degree of passive safe performances, compared to other type. However, it is still not clear if the present HTGR can maintain a passive safe function during a primary-pipe rupture accident, or what would be design criteria to guarantee the HTGR with the high degree of passive safe performances during the accident. To investigate safe characteristics, the study has been performed experimentally and analytically on the air ingress behavior during the accident. It was indicated that there are two stages in the accident of the HTGR having a reverse U-shaped channel. In the first stage, an air ingress process limits molecular diffusion and natural circulation of the gas mixture having a very slow velocity. In the second stage, the air ingress process limits the ordinary natural circulation of air throughout the reactor. A numerical calculation code has been developed to analyze thermal-hydraulic behavior during the first stage. This code provides a numerical method for analyzing a transport phenomena in a multi-component gas system by solving one-dimensional basic equations and using a flow network model. It was possible to predict or analyze the air ingress process regarding the density of the gas mixture, concentration of each gas species and duration of the first stage of the accident. It was indicated that the safe characteristics of the HTGR from the present experiment as follows. The safety cooling rate that the air ingress process terminates during the first stage exists in the HTGR having the reverse U-shaped channel. Moreover, the ordinary natural circulation of air can not produce in the second stage by injecting helium from the bottom of the pressure vessel corresponding the low-temperature side channel. Therefore, it was found that the idea of helium injection is one of useful methods for the prevention of air ingress and of graphite corrosion in the future HTGRs. (J.P.N.). 74 refs

  13. Experiment on Density Gradient Driven Flow in Small Break Air Ingress Accident of VHTRs

    International Nuclear Information System (INIS)

    This study measures amount of air-ingress rates through a small hole in a circular pipe for various break conditions. The main parameters considered are break orientation, break size, main flow velocity, and density ratio. The main objectives are summarized below: □ Understanding on fundamental air-ingress phenomena in the small break accident □ Development of flow regime map for the small break air-ingress □ Development of air-ingress model for VHTR safety analysis code. A Very High Temperature Reactor (VHTR) is one of the six Gen-IV reactor concepts which is adapting carbon layered TRISO-fuel, graphite-moderator, and helium-coolant. In spite of its inherent safety concept, the VHTR could be detrimental if a LOCA type accident occurs, which is followed by a pipe break. After the break, the air in the cavity starts to ingress into the reactor by either local density-gradient driven flow or molecular diffusion. The main concern of this accident is that it could eventually lead to structural degradation or release of the toxic and explosive gasses (CO) by oxidation of graphite. Previously, majority of the air-ingress studies have been focused on the large size break accident, which is called a double-ended-guillotine-break (DEGB). However, in this study, more focus in put on the small break (or leakage) accident, which is more realistic and probable in the VHTRs. According to the previous studies, the phenomena in the small break accident appear to be much more complicated than those in the DEGB, but little studies have been conducted and reported so far

  14. Feasibility study on naturally safe HTGR (NSHTR) for air ingress accident

    International Nuclear Information System (INIS)

    A new design activity for an advanced reactor, referred to as a naturally safe high temperature gas-cooled reactor (NSHTR), has been launched by authors after the accident at the Fukushima Daiichi Nuclear Power Station. The concept of NSHTR is that the release of radioactive materials is kept at very low level and no harmful effect on people and the environment is ensured by only physical phenomena even in the absence of engineered safety features. At an air ingress accident, possible physical events that lead to the loss or degradation of the confinement function of the fuel-coating layers are the crack of the coatings caused by the explosion of carbon monoxide (CO) produced by the graphite oxidation and failure of the coatings by melting or sublimation caused by core heat up due to the reaction heat of the graphite oxidation. In this study, the CO concentration and the heat generated by graphite oxidation inside the circular tube were evaluated parametrically using a steady-state one-dimensional model to confirm the feasibility of NSHTR at a severe condition of the air ingress accident (i.e., a massive air ingress by simultaneous rupture of two primary pipes). It was confirmed that the CO concentration at the outlet of coolant channel can be maintained below the explosion limit due to the reaction with oxygen in the air, and the reaction heat can be removed with the decay heat by physical phenomena under certain conditions of the coolant channel geometry without any engineered safety features. The results revealed that the design of NSHTR is technically feasible in terms of the suppression of the CO explosion and the heat removal of the reaction heat at the air ingress accident

  15. Computational Fluid Dynamics Analyses on Very High Temperature Reactor Air Ingress

    International Nuclear Information System (INIS)

    A preliminary computational fluid dynamics (CFD) analysis was performed to understand density-gradient-induced stratified flow in a Very High Temperature Reactor (VHTR) air-ingress accident. Various parameters were taken into consideration, including turbulence model, core temperature, initial air mole-fraction, and flow resistance in the core. The gas turbine modular helium reactor (GT-MHR) 600 MWt was selected as the reference reactor and it was simplified to be 2-D geometry in modeling. The core and the lower plenum were assumed to be porous bodies. Following the preliminary CFD results, the analysis of the air-ingress accident has been performed by two different codes: GAMMA code (system analysis code, Oh et al. 2006) and FLUENT CFD code (Fluent 2007). Eventually, the analysis results showed that the actual onset time of natural convection (∼160 sec) would be significantly earlier than the previous predictions (∼150 hours) calculated based on the molecular diffusion air-ingress mechanism. This leads to the conclusion that the consequences of this accident will be much more serious than previously expected

  16. The oxidation effects of nuclear graphite during air-ingress accidents in HTGR

    International Nuclear Information System (INIS)

    This study consists of two main parts. The first part presents an experimental investigation of two types of nuclear graphite (IG-110, IG-430) at temperatures ranging from 700 to 1000 °C. Mercury porosimetry results and the quantification of pores in SEM/OM image show that the pores (pore diameter >4 μm) tended to grow into larger pores at temperatures >700 °C. The second part of this study presents a simulation of air-ingress accident. This experiment was conducted at temperatures ranging from 800 to 1000 °C with a flow rate of 0.35 L/min to simulate an air-ingress accident. Results indicate that IG-430 showed a tremendous improvement over IG-110 at medium temperature (<800 °C). However, the advantages of IG-430 began to diminish when the temperature increased

  17. Possibility of air ingress into a BWR containment during a LOCA in case of activation of containment venting system

    International Nuclear Information System (INIS)

    The pressure relief systems installed in BWRs protect the containment from overpressure in case of a Loss of Coolant Accident (LOCA). This paper analyzes the possibility of air ingress, which can cause hydrogen burn, through the rupture disks of the filtered and non-filtered venting systems. Two scenarios were considered: a LOCA without SBO (Station Blackout) and a LOCA with SBO. The thermal-hydraulic code GOTHIC® was used with 3D models of the drywell and wetwell of a Nordic-type BWR. In the LOCA event, we found no activation of the rupture disks within the considered transient simulation. Moreover, the containment spray ensured a low pressure in the drywell and induced a continuous mixing of the wetwell pool. In the LOCA with SBO event, the development of thermal stratification in the wetwell pool accelerated the pressure increase in the drywell, which led to activation of the rupture disk of the filtered venting system. However, no air ingress through the vent was found during the depressurization of the containment, and hence no risk of hydrogen burn under the given assumptions. (author)

  18. ISOTHERMAL AIR INGRESS VALIDATION EXPERIMENTS AT IDAHO NATIONAL LABORATORY: DESCRIPTION AND SUMMARY OF DATA

    Energy Technology Data Exchange (ETDEWEB)

    Chang H. Oh; Eung S. Kim

    2010-09-01

    Idaho National Laboratory performed air ingress experiments as part of validating computational fluid dynamics code (CFD). An isothermal stratified flow experiment was designed and set to understand stratified flow phenomena in the very high temperature gas cooled reactor (VHTR) and to provide experimental data for validating computer codes. The isothermal experiment focused on three flow characteristics unique in the VHTR air-ingress accident: stratified flow in the horizontal pipe, stratified flow expansion at the pipe and vessel junction, and stratified flow around supporting structures. Brine and sucrose were used as heavy fluids and water was used as light fluids. The density ratios were changed between 0.87 and 0.98. This experiment clearly showed that a stratified flow between heavy and light fluids is generated even for very small density differences. The code was validated by conducting blind CFD simulations and comparing the results to the experimental data. A grid sensitivity study was also performed based on the Richardson extrapolation and the grid convergence index method for modeling confidence. As a result, the calculated current speed showed very good agreement with the experimental data, indicating that the current CFD methods are suitable for predicting density gradient stratified flow phenomena in the air-ingress accident.

  19. Simulation of the air ingress experiment QUENCH-16 with ATHLET-CD

    International Nuclear Information System (INIS)

    The severe accident analysis code ATHLET-CD is developed in order to analyze the behavior of Light-Water-Reactors under severe accident conditions. The objective of the code development is to provide a reliable tool for safety analysis of LWR, for instance, to assess the effectiveness of accident management measures at different stages of core degradation. Reflooding an uncovered core as a measure to prevent core damage may result in an accelerated zirconium oxidation. Besides a significant hydrogen generation, this reaction may cause a temperature escalation leading to the failure of the claddings. Therefore current research activities focus on the investigation of the behavior of fuel rod bundles during reflooding at high temperatures. In case of air ingress in the course of severe accidents, e. g. in dried-out spent fuel ponds, the high temperature interaction of fuel materials with air results in intense oxidation and nitriding of zirconium components. Under these conditions, severe bundle damages may occur even though the bundle can successfully be quenched by water. Two tests addressing the investigation of the bundle behaviour during air ingress followed by a subsequent bottom flooding with water have been performed in the QUENCH-facility at Karlsruhe Institute of Technology (KIT). The purpose of both air ingress tests, QUENCH-10 and QUNENCH-16, was to provide experimental data needed for model development as well as code validation. In contrast to QUENCH-10, the boundary conditions of QUENCH-16 in terms of the injection of air were chosen to extent the oxygen starvation period in order to investigate the impact of nitride formation on the bundle behaviour. The purpose of the post-test calculation of the experiment QUENCH-16 with the system code ATHLET-CD presented in this compact is to assess the current modeling of zirconium (Zr) oxidation in air. The results are presented and discussed in comparison to the measurements. (orig.)

  20. Simulation of the air ingress experiment QUENCH-16 with ATHLET-CD

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Mathias; Koch, Marco K. [Bochum Univ. (Germany). Chair of Energy Systems and Energy Economics (LEE)

    2012-11-01

    The severe accident analysis code ATHLET-CD is developed in order to analyze the behavior of Light-Water-Reactors under severe accident conditions. The objective of the code development is to provide a reliable tool for safety analysis of LWR, for instance, to assess the effectiveness of accident management measures at different stages of core degradation. Reflooding an uncovered core as a measure to prevent core damage may result in an accelerated zirconium oxidation. Besides a significant hydrogen generation, this reaction may cause a temperature escalation leading to the failure of the claddings. Therefore current research activities focus on the investigation of the behavior of fuel rod bundles during reflooding at high temperatures. In case of air ingress in the course of severe accidents, e. g. in dried-out spent fuel ponds, the high temperature interaction of fuel materials with air results in intense oxidation and nitriding of zirconium components. Under these conditions, severe bundle damages may occur even though the bundle can successfully be quenched by water. Two tests addressing the investigation of the bundle behaviour during air ingress followed by a subsequent bottom flooding with water have been performed in the QUENCH-facility at Karlsruhe Institute of Technology (KIT). The purpose of both air ingress tests, QUENCH-10 and QUNENCH-16, was to provide experimental data needed for model development as well as code validation. In contrast to QUENCH-10, the boundary conditions of QUENCH-16 in terms of the injection of air were chosen to extent the oxygen starvation period in order to investigate the impact of nitride formation on the bundle behaviour. The purpose of the post-test calculation of the experiment QUENCH-16 with the system code ATHLET-CD presented in this compact is to assess the current modeling of zirconium (Zr) oxidation in air. The results are presented and discussed in comparison to the measurements. (orig.)

  1. Experiments on the behaviour of ruthenium in air ingress accidents

    Energy Technology Data Exchange (ETDEWEB)

    Kaerkelae, T.; Backman, Ul; Auvinen, A.; Zilliacus, R.; Lipponen, M.; Kekki, T.; Tapper, U.; Jokiniemi, J. [Technical Research Centre of Finland VTT (Finland)

    2007-03-15

    During routine nuclear reactor operation, ruthenium will accumulate in the fuel in relatively high concentrations. In a severe accident in a nuclear power plant it is possible that air gets into contact with the reactor core. In this case ruthenium may oxidise and form volatile ruthenium species, RuO3 and RuO4, which can be transported into the containment. In order to estimate the amount of gaseous ruthenium species, it is of interest to know, how they are formed and how they behave. In our experiments the formation and transport of volatile ruthenium oxides was studied by exposing RuO2 powder to diverse oxidising atmospheres at a relatively high temperature. Transport of gaseous RuO4 was further investigated by injecting it into the facility in similar conditions. Upon cooling of the gas flow RuO2 aerosol particles were formed in the system. They were removed from the gas stream with plane filters. Gaseous ruthenium species were trapped in 1M NaOH-water solution, which is capable of trapping RuO4 totally. Ruthenium in the solution was filtered for analysis. The determination of ruthenium both in aerosol and in liquid filters was made using instrumental neutron activation analysis (INAA). In order to close the mass balance and to achieve better time resolution seven experiment were carried out using radioactive tracer. In this report, the facility for the ruthenium behaviour study and results from experiments are presented. Preliminary conclusions from the experiments are reported as well. Final conclusions will be made after modelling of the facility is completed in a continuation work of this study. (au)

  2. Experiments on the behaviour of ruthenium in air ingress accidents

    International Nuclear Information System (INIS)

    During routine nuclear reactor operation, ruthenium will accumulate in the fuel in relatively high concentrations. In a severe accident in a nuclear power plant it is possible that air gets into contact with the reactor core. In this case ruthenium may oxidise and form volatile ruthenium species, RuO3 and RuO4, which can be transported into the containment. In order to estimate the amount of gaseous ruthenium species, it is of interest to know, how they are formed and how they behave. In our experiments the formation and transport of volatile ruthenium oxides was studied by exposing RuO2 powder to diverse oxidising atmospheres at a relatively high temperature. Transport of gaseous RuO4 was further investigated by injecting it into the facility in similar conditions. Upon cooling of the gas flow RuO2 aerosol particles were formed in the system. They were removed from the gas stream with plane filters. Gaseous ruthenium species were trapped in 1M NaOH-water solution, which is capable of trapping RuO4 totally. Ruthenium in the solution was filtered for analysis. The determination of ruthenium both in aerosol and in liquid filters was made using instrumental neutron activation analysis (INAA). In order to close the mass balance and to achieve better time resolution seven experiment were carried out using radioactive tracer. In this report, the facility for the ruthenium behaviour study and results from experiments are presented. Preliminary conclusions from the experiments are reported as well. Final conclusions will be made after modelling of the facility is completed in a continuation work of this study. (au)

  3. Air and water ingress accidents in a HTR-modul of side-by-side concept

    International Nuclear Information System (INIS)

    Since the possibility of a temperature induced release of fission products from the core has been eliminated by the design of the HTR-Modul, the question arose whether corrosion by air can result in a significant release of fission products. Massive air ingress is only possible by natural convection and requires three large leaks in the pressure boundary at suitable positions (chimney effect). Such an event is hardly imaginable, since the occurrence of one leak already eliminates the mechanism for the formation of additional leaks. Nevertheless this highly hypothetical event was considered in order to get knowledge about the behaviour of the system under these extreme conditions. The results show that the maximal degree of corrosion of fuel elements remains low for a long period of time, since the corrosion zone moves through the pebble bed core. A massive release of fission products is significantly delayed, thus plenty of time is available for counter measures. Water ingress accidents proved to be dominant for the risk of a HTR-Modul. This is due to the fact that fission products deposited on the surface of the primary circuit can be remobilized by reaction with water and steam and can be released from the primary circuit via two release paths. One path leads via the relief valve and the ventilation system to the stack, the other via the steam generator leak and the dump line, if a dump line valve fails to close

  4. Separate-effects experiments on the hydrodynamics of air ingress phenomena for the very high temperature reactor

    International Nuclear Information System (INIS)

    The present study performs scaled separate-effects experiments to investigate the hydrodynamics in the air-ingress phenomena following a Depressurized Condition Cooldown in the Very High Temperature Gas-Cooled Reactor. First, a scoping experiment using water and brine is performed. The volumetric exchange rate is measured using a hydrometer, and flow visualizations are performed. Next, Helium-air experiments are performed to obtain three-dimensional oxygen concentration transient data using an oxygen analyzer. It is found that there exists a critical density difference ratio, before which the ingress rate increases linearly with time and after which the ingress rate slows down significantly. In both the water-brine and Helium-air experiments, this critical ratio is found to be approximately 0.7. (author)

  5. CODEX-AIT-2 experiment. Core degradation test with steam oxidation and air ingress

    International Nuclear Information System (INIS)

    The CODEX-AIT-2 test was performed in the CODEX facility in order to study the fuel rod degradation in the pre-oxidised bundle under air ingress conditions. The fuel rod cladding was oxidised in steam atmosphere in two steps: at 820 deg C and 950 deg C to give an oxide layer thickness of 20-25 microns. After the air injection temperature excursion was observed on the fuel rods to a maximum indicated temperature of 1900 deg C. In the AIT-2 test the damage of the bundle was more severe than in the first test, for the high temperature conditions were kept for longer time in AIT-2 than in AIT-1. The rod-like structure was lost in the upper part of the bundle. The formation of higher uranium oxides was not observed. (author)

  6. Effect of air ingress on the energy performance of coal fired thermal power plants

    International Nuclear Information System (INIS)

    Ingress of air in boilers leads to drops in energy efficiency. This paper presents the effects of air ingress in the combustion zone, post-combustion zone and air pre-heater (APH) on the energy efficiency and loading capacity of a coal fired thermal power plant operating on fuel with high ash (35-45%). The optimal O2 in the flue gas for a pulverized coal fired system is 3.5% (corresponding to 20% excess air). The operating values are in the range of 4.2-6.0% in membrane type boilers and up to 10% in refractory type boilers (after sustained periods of operation). The leakage rate of boilers (up to the entrance of the APH) is designed at 0.2% while the average operating values are 7.25% for membrane type enclosures and 33.61% for refractory enclosures. The leakage rate of the APH is designed at 5.0% while the operating values range from 13.66% to 20.13% for rotary and tubular APHs. When the O2 in the combustion zone varies from 3.5% to 8.0%, efficiency drops of 2.0% points are experienced in the boiler and turbine separately, and the gross overall efficiency drop is ∼3.0% points. The units do not experience any capacity drop up to an O2 in the flue gas of 6.0% before the APH. At an O2 in the flue gas (before APH) of 7.2%, a mild limitation on the unit capacity of around 2-3% is experienced. When O2 in the flue gas (before APH) reaches a level of 9.0%, 20% capacity drop of the unit is experienced due to which the plant load cannot be raised higher than 80%. Beyond the level of 9.0% (rare occurrence), the unit is quite difficult to operate and has to be taken off for overhaul

  7. Separate-effect tests on zirconium cladding degradation in air ingress situations

    Energy Technology Data Exchange (ETDEWEB)

    Duriez, C. [Institut de Radioprotection et de Surete Nucleaire, IRSN, Direction de Prevention des Accidents Majeurs, Centre de Cadarache, 13115 St Paul Lez Durance (France)], E-mail: christian.duriez@irsn.fr; Steinbrueck, M. [Forschungszentrum Karlsruhe, FZK, Institut fuer Materialforschung, Postfach 3640, 76021 Karlsruhe (Germany); Ohai, D.; Meleg, T. [Institute for Nuclear Research, INR, Nuclear Material and Corrosion Department, Pitesti, 115400 Mioveni Arges (Romania); Birchley, J.; Haste, T. [Paul Scherrer Institute, 5232 Villigen PSI (Switzerland)

    2009-02-15

    In the event of air ingress during a reactor or spent fuel pond low probability accident, the fuel rods will be exposed to air-containing atmospheres at high temperatures. In comparison with steam, the presence of air is expected to result in a more rapid escalation of the accident. A state-of-the-art review performed before SARNET started showed that the existing data on zirconium alloy oxidation in air were scarce. Moreover, the exact role of zirconium nitride on the cladding degradation process was poorly understood. Regarding the cladding behaviour in air + steam or nitrogen-enriched atmospheres (encountered in oxygen-starved conditions), almost no data were available. New experimental programmes comprising small-scale tests have therefore been launched at FZK, IRSN (MOZART programme in the frame of the International Source Term Program-ISTP) and INR. Zircaloy-4 cladding in PWR (FZK, IRSN) and in CANDU (INR) geometry are investigated. On-line kinetic data are obtained on centimetre size tube segments, by thermogravimetry (FZK, IRSN and INR) or by mass spectrometry (FZK). Plugged tubes 15 cm long (FZK) are also investigated. The samples are air-oxidised either in the 'as-received' state, or after pre-oxidation in steam. 'Analytical' tests at constant temperature and gas composition provide basic kinetic data, while more prototypical temperature transients and sequential gas compositions are also investigated. The temperature domains extend from 600 deg. C up to 1500 deg. C. Systematic post-test metallographic inspections are performed. The paper gives a synthesis of the results obtained, comparing them in terms of kinetics and oxide scale structure and composition. A comparative analysis is performed with results of the QUENCH-10 (Q-10) bundle test, which included an air ingress phase. It is shown how the data contribute to a better understanding of the cladding degradation process, especially regarding the role of nitrogen. For modelling of

  8. Air ingress and graphite burning in HTRs: A survey on analytical examinations performed with the code React/Thermix

    International Nuclear Information System (INIS)

    Analyses on air ingress in the pebble bed reactors PNP-500, THTR-300, HTR-Modul, AVR-II and AVR process heat plant are outlined; in addition, some results for the VHTR with block type fuel are given. Air ingress requires primary circuit depressurization and large leak(s) to reactor buildings and environment and belongs therefore to highly hypothetical events in the sense of classical safety analysis. One accident class examined is air ingress with forced flow by emergency cooling: For this case, the range of mass flow/air content in cooling gas has been evaluated, in which safe core cool down is possible resp. long term core burning occurs; for highest available emergency cooling flow, a safe cool down of the THTR-300, which has no reactor building, is possible for up to 20 vol-% of air in the cooling gas, wheras low flow allows only for about 5 vol-%. If the amount of available air is restricted to the content of a reactor building, as is examined for the PNP-500, relevant consequences have not to be expected; this remains also true for forced convection flow, if burning of CO, formed by graphite oxidation, within the building is considered. For the second accident class examined, air ingress with natural convection flow by chimney draught as studied for the HTR-Modul and some other concepts, the time span until significant fission product release begins has been determined; in case, that the bottom reflector is hot at accident start (> 600 C) and therefore consumes most of the ingressing oxygen, this time span is at least several hours and leak tightening counter measures may be possible. (orig./HP)

  9. Experiments on the transfer of heat and mass as a result of natural convection in the event of an air ingress accident in a high-temperature reactor

    International Nuclear Information System (INIS)

    To facilitate nuclear technology with high-temperature reactors without any risk of serious accidents, it is necessary to ensure that even the largest accidents will not have any significant effect on the area around the power station. In this case, it is vital to ensure the chemical stability of those reactors if there is an ingress of air as a result of an accident. A large-scale test installation is currently in operation at the Institute of Safety Research and Reactor Technology in the Research Centre Juelich. It is used to investigate the sequence of events and consequences of air ingress accidents of that kind. The experiments are designed to ascertain what the possible extent of the damage will be in certain scenarios and also to develop possible concepts for counteracting the damage and safeguarding the chemical stability of the system. Numerous experiments have been conducted on flow and mass transfer in the course of this study. These experiments describe the individual physical processes within the test installation. The findings derived from this on plant-specific loss of pressure, transfer of heat and material allow to interpret accident simulation experiments reliably and ensure that this data can be applied to the situation in high-temperature reactors using computer programs. (orig.)

  10. Estimation of graphite density and mechanical strength variation of VHTR during air-ingress accident

    International Nuclear Information System (INIS)

    An air-ingress accident in a Very High Temperature Gas-Cooled Reactor (VHTR) is anticipated to cause severe changes to graphite density and mechanical strength by an oxidation process that has many side effects. However, quantitative estimations have not yet been performed. This study focuses on predicting the changes in graphite density and mechanical strength via thermal hydraulic system analysis code. In order to analyze the change in graphite density, a simple graphite burn-off model was developed. The model is based on the similarities between a parallel electrical circuit and graphite oxidation. It was used to determine overall changes in the graphite's geometry and density. The model was validated by comparing its results to experimental data that was obtained for several temperatures. In the experiment, cylindrically shaped graphite specimens were oxidized in an electrical furnace and the variations of its mass were measured against time. The experiment's range covered temperatures between 6000 C and 9000 C. Experimental data validated the model's accuracy. Finally, the developed model along with other comprehensive graphite oxidation models was integrated into the VHTR system analysis code, GAMMA. GT-MHR 600 MWt reactor was selected as a reference reactor. Based on the calculation, the main oxidation process was observed 5.5 days after the accident when followed by natural convection. The core maximum temperature reached 16000 C, but never exceeded the maximum temperature criteria, 18000 C. However, the oxidation process did significantly decrease the density of bottom reflector, making it vulnerable to mechanical stress. The stress on the bottom reflector is greatly increased because it sustains the reactor core. The calculation proceeded until 11 days after the accident, resulting in an observed 4.5% decrease in density and a 25% reduction of mechanical strength

  11. Oxidation kinetics of innovative carbon materials with respect to severe air ingress accidents in HTRs and graphite disposal or processing

    International Nuclear Information System (INIS)

    Currently future nuclear reactor concepts of the Fourth Generation (Gen IV) are under development. To some extend they apply with new, innovative materials developed just for this purpose. This thesis work aims at a concept of Generation IV Very High Temperature Reactors (VHTR) in the framework of the European project RAPHAEL (ReActor for Process heat, Hydrogen And ELectricity generation). The concept named ANTARES (AREVA New Technology based on advanced gas-cooled Reactors for Energy Supply) was developed by AEVA NP. It is a helium cooled, graphite moderated modular reactor for electricity and hydrogen production, by providing the necessary process heat due to its high working temperature. Particular attention is given here to oxidation kinetics of newly developed carbon materials (NBG-17) with still unknown but needed information in context of severe air ingress accident in VHTR's. Special interest is paid to the Boudouard reaction, the oxidation of carbon by CO2. In case of an air ingress accident, carbon dioxide is produced in the primary reaction of atmospheric oxygen with reflector graphite. From there CO2 could flow into the reactor core causing further damage by conversion into CO. The purpose of this thesis is to ascertain if and to what degree this could happen. First of all oxidation kinetic data of the Boudouard reaction with NBG-17 is determined by experiments in a thermo gravimetric facility. The measurements are evaluated and converted into a common formula and a Langmuir-Hinshelwood similar oxidation kinetic equation, as input for the computer code REACT/THERMIX. This code is then applied to analyse severe air ingress accidents for several air flow rates. The results are discussed for two accident situations, in which a certain graphite burn off is achieved. All cases show much more damage to the graphite bottom reflector than to the reactor core. Thus the bottom reflector will lose its structural integrity much earlier than the core itself will be

  12. Experimental investigations of graphite corrosion and aerosol formation during air ingress into the core of a high temperature pebble bed reactor

    International Nuclear Information System (INIS)

    A High Temperature Reactor can be designed to remove the decay heat without using any active systems. For most accident scenarios a release of radioactive fission products can be excluded by design. However, during operation of a HTR some accidents are principally possible, which can result in a release of fission products out of the fuel elements and of the reactor system. One of these accidents is a hypothetical massive air ingress into the hot graphite reactor core. After a pressure drop caused by leakages in the primary circuit a gas mass flow may be able to stream through the core according to free natural convection leading to a corrosion of the graphite fuel elements and reflector structures. With the VELUNA-experiment a testing device was installed, which allows to investigate the corrosion process on parts of a reactor core under real accident conditions. With regard to the experimental results already existing equations to calculate the chemical reaction rate in a pebble bed were modified and the applicability was demonstrated. These equations consider the chemical reaction in the porous graphite as well as diffusion processes to the graphite surface. Equivalent correlations were developed for different flow geometries and for the graphite material of the bottom reflector. The corrosion process forms an aerosol, which consists of graphite particles and a reaction gas phase. The formatted aerosol was characterized concerning its chemical and physical properties. Because the aerosol particles can support the release of fission products, measurements of aerosol parameters like particle mass concentration and particle size distribution provide important information to estimate the radiologic consequences of such an hypothetical air ingress accident. (orig.)

  13. Emission scenario model for regional air pollution

    OpenAIRE

    Karvosenoja, Niko

    2008-01-01

    Air pollution emissions are produced in a wide variety of sources. They often result in detrimental impacts on both environments and human populations. To assess the emissions and impacts of air pollution, mathematical models have been developed. This study presents results from the application of an air pollution emission model, the Finnish Regional Emission Scenario (FRES) model, that covers the emissions of sulfur dioxide (SO2), nitrogen oxides (NOx), ammonia (NH3), non-methane volatile or...

  14. Analysis of diffusion process and influence factors in the air ingress accident of the HTR-PM

    International Nuclear Information System (INIS)

    Air ingress, one of the beyond design basis accidents for high temperature gas-cooled reactors, receives high attention during the design of the 250 MW pebble-bed modular high temperature gas-cooled reactor (HTR-PM), because it may result in severe consequence including the corrosion of the fuel element and graphite reflector. The diffusion process and the set-up time of the stable natural convection after the double-ended guillotine break of the hot-gas duct are studied in the paper. On the basis of the preliminary design of the HTR-PM and its DLOCA analysis results, the diffusion process, as well as the influence of the core temperature distribution and the length of the hot-gas duct, is studied with the DIFFLOW code, which adopts a one-dimension variable cross-section diffusion model with fixed wall temperature. To preliminarily estimate the influence of chemical reaction between oxygen and graphite, which will change the gas component of the mixture, the diffusion processes between the He/N2, He/O2, He/CO and He/CO2 are calculated, respectively. Furthermore, the code has been improved and the varying wall temperature can be simulated. The more accurate analysis is carried out with the changing temperature distribution from the DLOCA calculation. The analysis shows that there is enough time to adopt appropriate mitigation measures to stop the air ingress and the severe consequence of fuel element damage and large release of fission product can be avoided

  15. Numerical simulation of the gas diffusion process during an air ingress accident in the HTR-PM

    International Nuclear Information System (INIS)

    The consequence of an air ingress accident can be greatly influenced by the gas-diffusion process. It is necessary to study the process of air diffusion in the cavity of the reactor through the rupture of hot gas ducts of the High Temperature Gas-cooled Reactor Pebble-bed Module (HTR-PM) until steady convection forms. The DIFFLOW code was used for the numerical simulation that illustrated the gas-diffusion process inside of the HTR-PM. In the sensitivity analysis, the core temperature, the diffusion coefficient, the frictional resistance coefficient and the surface coefficient of heat transfer proved to be the impact factors. Each factor was evaluated with three levels. The onset time of the steady convection, the velocity in the middle passage under steady convection, and the mass flow in the middle passage under steady convection were observed in the analysis. 32.78 hours after the accident occurs, the steady convection could be established. The flow in the middle passage under steady convection measured 0.32kg/s, while the velocity in the middle passage read 0.56m/s. The sensitivity analysis also showed that the core temperature had a remarkable impact on the onset time, the velocity and the flow of the steady convection. (author)

  16. Experiments on mass transfer in a natural convection of high temperature gas mixture with graphite corrosion due to air ingress

    International Nuclear Information System (INIS)

    Experiments on mass transfer in a natural convection of gas mixture with graphite corrosion at high temperature due to air ingress have been performed to predict the thermohydraulic characteristics with high accuracy at the pipe rupture in a high temperature gas cooled reactor. The whole shape of the multi-channel test section is a reverse U shape. The one side of the reverse U shaped test section consists of two hot graphite channels and one cold metal channel which are parallel to each other. The inlet and outlet mole fractions of oxygen, carbon monoxide and carbon dioxide, the corrosion thickness of the graphite tube, the distribution of flow rates were measured under the various temperature conditions of graphite channels up to 1200degC. From these data, the relationship of Sherwood number and dimensionless distance from the inlet of the graphite channel have been obtained. It was found under the present experimental conditions that the maximum mole fraction of carbon monoxide at the outlet is 0.25% and the Sherwood numbers obtained are smaller than those calculated on assumption of analogy between heat and mass transfer. (author)

  17. CODEX-AIT-1 experiment. Core degradation test under air ingress

    International Nuclear Information System (INIS)

    The CODEX (COre Degradation EXperiment) facility was used to provide experimental data on the behaviour of real fuel bundles under air oxidation conditions. The CODEX-AIT-1 experiment was carried out with electrically heated 9-rod PWR type bundle. Temperature, flowrate, pressure measurements were recorded during the tests. Pyrometers and high temperature thermocouples were used for temperature measurements. Aerosol release was measured using on-line particle counters and cascade impactors. The test indicated the acceleration of oxidation phenomena and core degradation processes during the late phase of the vessel melt through accident, when the air can have access to the residual fuel bundles in the reactor core. The degradation process was accompanied with zirconium-nitride formation and release of U-rich aerosol. (author)

  18. Courses and limitations of damage with air ingress accidents in HTR modules

    International Nuclear Information System (INIS)

    If air can penetrate into the reactor and flow through the core for a long time, e.g. 24 hours, major corrosion damage will occur. This can happen if sufficiently large openings enable a steady natural convection gas flow within the reactor, and if there is a steady supply of air. In the event of a break of the connection between the two main vessels, the reactor cell can be expected to incur severe damage, giving access to air from outside the cell. About 80 hours after the depressurization, a natural convection airflow starts through the reactor. Coated particles equivalent to about 200 spheres are estimated to be set free from corroded fuel elements within 24 hours. At 1300 deg C, they stay intact for ∼ 250 hours. At ≤1200 deg C, they will stay intact, i.e. have no release for even longer times. A pressure relief channel for mass flows after large breaks is discussed to ensure the integrity of the reactor cell in this case. (author)

  19. Experiments on the behaviour of ruthenium in air ingress accidents - Progress report

    International Nuclear Information System (INIS)

    During routine nuclear reactor operation, ruthenium will accumulate in the fuel in relatively high concentrations. In an accident in a nuclear power plant it is possible that air gets into contact with the reactor core. In this case ruthenium can oxidise and form volatile ruthenium species, RuO3 and RuO4, which can be transported into the containment. In order to estimate the amount of gaseous ruthenium species it is of interest to know, how it is formed and how it behaves. In our experiments RuO2 is exposed to diverse oxidising atmospheres at a relatively high temperature. In this report, the experimental system for the ruthenium behaviour study is presented. Also preliminary results from experiments carried out during year 2005 are reported. In the experiments gaseous ruthenium oxides were produced in a furnace. Upon cooling RuO2 aerosol particles were formed in the system. They were removed with plane filters from the gas stream. Gaseous ruthenium species were trapped in 1M NaOH-water solution, which is capable of trapping RuO4 totally. Ruthenium in the solution was filtered for analysis. The determination of ruthenium both in aerosol and in liquid filters was made using instrumental neutron activation analysis (INAA). In order to close mass balance and achieve better time resolution three experiment using radioactive tracer were carried out. (au)

  20. Containment Performance Evaluation of a Sodium Fire Event Due to Air Ingress into the Cover Gas Region of the Reactor Vessel in the PGSFR

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Sang June; Chang, Won-Pyo; Kang, Seok Hun; Choi, Chi-Woong; Yoo, Jin; Lee, Kwi Lim; Jeong, Jae-Ho; Lee, Seung Won; Jeong, Taekyeong; Ha, Kwi-Seok [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Comparing with the light water reactor, sodium as a reactor coolant violently reacts with oxygen in the containment atmosphere. Due to this chemical reaction, heat generated from the combustion heat increases the temperature and pressure in the containment atmosphere. The structural integrity of the containment building which is a final radiological defense barrier is threaten. A sodium fire event in the containment due to air ingress into the cover gas region in the reactor vessel is classified as one of the design basis events in the PGSFR. This event comes from a leak or crack on the reactor upper closure header surface. It accompanys an event of the radiological fission products release to the inside the containment. In this paper, evaluation for the sodium fire and radiological influence due to air ingress into the cover gas region of the reactor vessel is described. To evaluate this event, the CONTAIN-LMR, MACCS-II and OR-IGEN-II codes are used. For the sodium pool fire event in the containment, the performance evaluation and radiological influence are carried out. In the thermal hydraulic aspects, the 1 cell containment yields the most conservative result. In this event, the maximum temperature and pressure in the containment are calculated 0.185 MPa, 280.0 .deg. C, respectively. The radiological dose at the EAB and LPZ are below the acceptance criteria specified in the 10CFR100.

  1. Containment Performance Evaluation of a Sodium Fire Event Due to Air Ingress into the Cover Gas Region of the Reactor Vessel in the PGSFR

    International Nuclear Information System (INIS)

    Comparing with the light water reactor, sodium as a reactor coolant violently reacts with oxygen in the containment atmosphere. Due to this chemical reaction, heat generated from the combustion heat increases the temperature and pressure in the containment atmosphere. The structural integrity of the containment building which is a final radiological defense barrier is threaten. A sodium fire event in the containment due to air ingress into the cover gas region in the reactor vessel is classified as one of the design basis events in the PGSFR. This event comes from a leak or crack on the reactor upper closure header surface. It accompanys an event of the radiological fission products release to the inside the containment. In this paper, evaluation for the sodium fire and radiological influence due to air ingress into the cover gas region of the reactor vessel is described. To evaluate this event, the CONTAIN-LMR, MACCS-II and OR-IGEN-II codes are used. For the sodium pool fire event in the containment, the performance evaluation and radiological influence are carried out. In the thermal hydraulic aspects, the 1 cell containment yields the most conservative result. In this event, the maximum temperature and pressure in the containment are calculated 0.185 MPa, 280.0 .deg. C, respectively. The radiological dose at the EAB and LPZ are below the acceptance criteria specified in the 10CFR100

  2. Response of fuel, fuel elements and gas cooled reactor cores under accidental air or water ingress conditions. Proceedings of a technical committee meeting held in Beijing, China, 25-27 October 1993

    International Nuclear Information System (INIS)

    The meeting was convened by the IAEA on the recommendation of the IAEA's International Working Group on Gas Cooled Reactors. It was attended by participants from China, France, Germany, Japan, Netherlands, Switzerland, the Russian Federation, the United Kingdom and the United States of America. The meeting covered the following topics: experimental investigations of the effects of air and water ingress; predicted response of fuel, graphite and other reactor components; options for minimizing or mitigating the effects of air or water ingress. 19 papers were presented at the meeting. A separate abstract was prepared for each of these papers. Refs, figs and tabs

  3. Generating scenarios to predict air quality impact in public health

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, J.M.; Coelho, L.M.R.; Gouveia, C.; Cerdeira, R. [Escola Superior de Tecnologia de Setubal (EST-IPS), Setubal (Portugal); Ferreira, T.; Baptista, M.N. [Hospital Na. Sa. do Rosario, Servico de Pediatria, Barreiro (Portugal)

    2004-07-01

    This study intends to associate air quality with public health by generating air quality scenarios, under different future perspectives in Barreiro. This city is located in middle south of Portugal nearby Lisbon and it has a large resident population, an important industrial area and intense traffic. In this study ADMS-urban was used to simulate the possible scenarios of future air quality in this city, taking into consideration the probable city development and future activities. Special attention was given to the future evolutions of traffic, industrial activities, demographical and geographical expansion. The new EU directives about air quality and the CAFE program were also considered. To correlate the impact of the future air quality of the city and public health, a children population sample was used. This study team is also composed by paediatric doctors from Hospital N{sup a}. S{sup a}. do Rosario that contribute with public health information and helped to identify air quality related diseases. (orig.)

  4. Megacity ozone air quality under four alternative future scenarios

    Directory of Open Access Journals (Sweden)

    T. M. Butler

    2012-05-01

    Full Text Available The impact of the megacities of the world on global tropospheric ozone, and conversely, the extent to which megacities are influenced by emissions of ozone precursors from outside of the megacities is examined under the four alternative RCP ("Representative Concentration Pathway" emissions scenarios. Despite accounting for about 6% of present-day anthropogenic emissions of ozone precursor species, the contribution of emissions from megacities to global tropospheric ozone is calculated to be 0.84%. By 2100 this contribution falls to between 0.18% and 0.62% depending on the scenario, with the lower value being for the most-polluting of the four future emissions scenarios due to stringent controls on ozone precursor emissions from highly populated areas combined with a stronger tropospheric background ozone field. The higher end of this range is from the least-polluting of the four emissions scenarios, due to lower background tropospheric ozone combined with the use of a simpler downscaling methodology in the construction of the scenario, which results in higher emissions from megacities. Although the absolute impact of megacities on global ozone is small, an important result of this study is that under all future scenarios, future air quality in megacities is expected to be less influenced by local emissions within the cities, but instead more influenced by emission sources outside of the cities, with mixing ratios of background ozone projected to play an increasing role in megacity air quality throughout the 21st century. Assumptions made when downscaling the emissions scenarios onto the grids used in such modelling studies can have a large influence on these results; future generations of emissions scenarios should include spatially explicit representations or urban development suitable for air quality studies using global chemical transport models.

  5. Megacity ozone air quality under four alternative future scenarios

    Directory of Open Access Journals (Sweden)

    T. M. Butler

    2012-01-01

    Full Text Available The impact of the megacities of the world on global tropospheric ozone, and conversely, the extent to which megacities are influenced by emissios of ozone precursors from outside of the megacities is examined under the four alternative RCP (''Representative Concentration Pathway'' emissions scenarios. Despite accounting for about 6% of present-day anthropogenic emissions of ozone precursor species, the contribution of emissions from megacities to global tropospheric ozone is calculated to be 0.84%. By 2100 this contribution falls to between 0.18 and 0.62% depending on the scenario, with the lower value being for the most-polluting of the four future emissions scenarios due to stringent controls on ozone precursor emissions from highly populated areas combined with a stronger tropospheric background ozone field. The higher end of this range is from the least-polluting of the four emissions scenarios, due lower background tropospheric ozone combined with the use of a different downscaling methodology in the construction of the scenario. Although the absolute impact of megacities on global ozone is small, an important result of this study is that under all future scenarios, future air quality in megacities is expected to be less influenced by local emissions within the cities, but instead more influenced by emission sources outside of the cities. Air quality trends in the megacities of the developing world are projected to be similar to observed trends in developed world megacities over the last few decades. Assumptions made when downscaling the emissions scenarios onto the grids used in such modelling studies can have a large influence on these results. Future work should concentrate on the creation of spatially explicit scenarios of urban development for use in global chemical transport models.

  6. Chloride ingress prediction

    DEFF Research Database (Denmark)

    Frederiksen, Jens Mejer; Geiker, Mette Rica

    2008-01-01

    Prediction of chloride ingress into concrete is an important part of durability design of reinforced concrete structures exposed to chloride containing environment. This paper presents experimentally based design parameters for Portland cement concretes with and without silica fume and fly ash in...

  7. Modelling Domestic Air Transport Demand and Evaluating under Scenarios

    OpenAIRE

    Cenk OZAN; Özgür BAŞKAN; Haldenbilen, Soner; Ceylan, Halim

    2014-01-01

    The lack of balance and integration between transportation modes in Turkey is one of the main problems. In this study, domestic air transport demand is modeled and evaluated under scenarios. For this purpose, indexing method which is able to indicate observed monthly and seasonal variations in demand is used. Proposals are suggested in order to overcome the lack of balance between transportation modes. In modeling, purchasing power parity and jet fuel prices as independent variables are used....

  8. Chloride ingress prediction

    DEFF Research Database (Denmark)

    Frederiksen, Jens Mejer; Geiker, Mette Rica

    Prediction of chloride ingress into concrete is an important part of durability design of reinforced concrete structures exposed to chloride containing environment. This paper presents experimentally based design parameters for Portland cement concretes with and without silica fume and fly ash in...... marine atmospheric and submersed South Scandinavian environment. The design parameters are based on sequential measurements of 86 chloride profiles taken over ten years from 13 different types of concrete. The design parameters provide the input for an analytical model for chloride profiles as function...

  9. Modelling Domestic Air Transport Demand and Evaluating under Scenarios

    Directory of Open Access Journals (Sweden)

    Cenk Ozan

    2014-09-01

    Full Text Available The lack of balance and integration between transportation modes in Turkey is one of the main problems. In this study, domestic air transport demand is modeled and evaluated under scenarios. For this purpose, indexing method which is able to indicate observed monthly and seasonal variations in demand is used. Proposals are suggested in order to overcome the lack of balance between transportation modes. In modeling, purchasing power parity and jet fuel prices as independent variables are used. Results showed that the developed model using indexing method is substantially sensitive to observed monthly and seasonal variations in domestic air transport demand. Furthermore, in the event that there are optimistic an increase in the income level and a crawl in the jet fuel prices, domestic air transport can rival with railways for second place in the transportation modes behind highways. For this reason, it is considered regulation on wages policy and tax of jet fuel prices necessary to support development of domestic air transport demand.

  10. Chloride ingress prediction

    DEFF Research Database (Denmark)

    Frederiksen, Jens Mejer; Geiker, Mette Rica

    Prediction of chloride ingress into concrete is an important part of durability design of reinforced concrete structures exposed to chloride containing environment. This paper presents the state-of-the art: an analytical model which describes chloride profiles in concrete as function of depth and...... makes physical sense for the design engineer, i.e. the achieved chloride diffusion coefficients at 1 year and 100 years, D1 and D100 respectively, and the corresponding achieved chloride concentrations at the exposed concrete surface, C1 and C100. Data from field exposure supports the assumption of time...... dependent surface chloride concentrations and the diffusion coefficients. Model parameters for Portland cement concretes with and without silica fume and fly ash in marine atmospheric and submerged South Scandinavian environment are suggested in a companion paper based on 10 years field exposure data....

  11. Oxidation kinetics of innovative carbon materials with respect to severe air ingress accidents in HTRs and graphite disposal or processing; Oxidationskinetik innovativer Kohlenstoffmaterialien hinsichtlich schwerer Lufteinbruchstoerfaelle in HTR's und Graphitentsorgung oder Aufbereitung

    Energy Technology Data Exchange (ETDEWEB)

    Schloegel, Baerbel

    2010-07-01

    Currently future nuclear reactor concepts of the Fourth Generation (Gen IV) are under development. To some extend they apply with new, innovative materials developed just for this purpose. This thesis work aims at a concept of Generation IV Very High Temperature Reactors (VHTR) in the framework of the European project RAPHAEL (ReActor for Process heat, Hydrogen And ELectricity generation). The concept named ANTARES (AREVA New Technology based on advanced gas-cooled Reactors for Energy Supply) was developed by AEVA NP. It is a helium cooled, graphite moderated modular reactor for electricity and hydrogen production, by providing the necessary process heat due to its high working temperature. Particular attention is given here to oxidation kinetics of newly developed carbon materials (NBG-17) with still unknown but needed information in context of severe air ingress accident in VHTR's. Special interest is paid to the Boudouard reaction, the oxidation of carbon by CO{sub 2}. In case of an air ingress accident, carbon dioxide is produced in the primary reaction of atmospheric oxygen with reflector graphite. From there CO{sub 2} could flow into the reactor core causing further damage by conversion into CO. The purpose of this thesis is to ascertain if and to what degree this could happen. First of all oxidation kinetic data of the Boudouard reaction with NBG-17 is determined by experiments in a thermo gravimetric facility. The measurements are evaluated and converted into a common formula and a Langmuir-Hinshelwood similar oxidation kinetic equation, as input for the computer code REACT/THERMIX. This code is then applied to analyse severe air ingress accidents for several air flow rates. The results are discussed for two accident situations, in which a certain graphite burn off is achieved. All cases show much more damage to the graphite bottom reflector than to the reactor core. Thus the bottom reflector will lose its structural integrity much earlier than the

  12. Scenarios

    International Nuclear Information System (INIS)

    Scenarios provide a framework for exploring future energy perspectives, including a continuation of current dynamics and alternative paths developed on the basis of different assumptions relevant to sustainable energy development. It is important to note that scenarios are neither forecasts nor predictions, but are images of alternative futures based on internally consistent and reproducible sets of assumptions. Thus, scenario outputs and assumptions are inseparable parts of the overall integrated modelling process. This section presents alternative scenarios developed for Cuba for the period 2002-2025. One basic reference (REF) scenario is developed to explore future paths for both energy demand and supply. The optimization of the supply system is further analysed by the development of three alternative scenarios in addition to the REF scenario: a fossil fuels (FOS) scenario that emphasizes the use of fossil fuels; a renewables (REN) scenario that emphasizes intense use of renewables; and a mixed fuels (MIX) scenario that combines assumptions about the use of fossil fuels and renewables. Finally, a sensitivity analysis is performed in which alternative assumptions related to imported crude oil and petroleum products prices are taken into consideration. This section summarizes the methodology, assumptions and resulting characterizations of these alternative scenarios

  13. Insights into future air quality: a multipollutant analysis of future scenarios using the MARKAL model

    Science.gov (United States)

    In this presentation, we will provide an update on the development and evaluation of the Air Quality Futures (AQF) scenarios. These scenarios represent widely different assumptions regarding the evolution of the U.S. energy system over the next 40 years. The four AQF scenarios di...

  14. Study of water ingression models

    International Nuclear Information System (INIS)

    It is important to understand the mechanisms of quenching molten corium material when estimating the safety of nuclear plants. The melt freezes creating an impermeable crust when water is injected on the top of the molten pool. The heat is carried away from the melt only by conduction through the crust and thus the cooling rate decreases as the crust grows. Cracking of the crust allows water to penetrate into the crust making conduction layer thinner and increasing the cooling rate. This is called water ingression. The water ingression model presented here is partly based on experimental data obtained for rocks, and thus it is not clear if it can be used in the case of corium pools. If it is permissible to extrapolate this theory to relatively hightemperature corium, the water ingression is not possible with the corium pools. However, the theory is sensitive to errors with high temperatures. Experiments have shown that the cooling rate of the corium pools is higher than it should be with conduction only and careful analyses of experiments are required to verify the nature and scale of water ingression process. (orig.)

  15. Insights into future air quality: Analysis of future emissions scenarios using the MARKAL model

    Science.gov (United States)

    This presentation will provide an update on the development and evaluation of four Air Quality Futures (AQF) scenarios. These scenarios represent widely different assumptions regarding the evolution of the U.S. energy system over the next 40 years. The primary differences between...

  16. Scenarios

    Directory of Open Access Journals (Sweden)

    Joao M. Goncalves

    2015-12-01

    Full Text Available Personal information is increasingly gathered and used for providing services tailored to user preferences, but the datasets used to provide such functionality can represent serious privacy threats if not appropriately protected. Work in privacy-preserving data publishing targeted privacy guarantees that protect against record re-identification, by making records indistinguishable, or sensitive attribute value disclosure, by introducing diversity or noise in the sensitive values. However, most approaches fail in the high-dimensional case, and the ones that don't introduce a utility cost incompatible with tailored recommendation scenarios. This paper aims at a sensible trade-off between privacy and the benefits of tailored recommendations, in the context of privacy-preserving data publishing. We empirically demonstrate that significant privacy improvements can be achieved at a utility cost compatible with tailored recommendation scenarios, using a simple partition-based sanitization method.

  17. European atmosphere in 2050, a regional air quality and climate perspective under CMIP5 scenarios

    Directory of Open Access Journals (Sweden)

    A. Colette

    2013-08-01

    Full Text Available To quantify changes in air pollution over Europe at the 2050 horizon, we designed a comprehensive modelling system that captures the external factors considered to be most relevant, and that relies on up-to-date and consistent sets of air pollution and climate policy scenarios. Global and regional climate as well as global chemistry simulations are based on the recent representative concentration pathways (RCP produced for the Fifth Assessment Report (AR5 of the IPCC (Intergovernmental Panel on Climate Change whereas regional air quality modelling is based on the updated emissions scenarios produced in the framework of the Global Energy Assessment. We explored two diverse scenarios: a reference scenario where climate policies are absent and a mitigation scenario which limits global temperature rise to within 2 °C by the end of this century. This first assessment of projected air quality and climate at the regional scale based on CMIP5 (5th Coupled Model Intercomparison Project climate simulations is in line with the existing literature using CMIP3. The discrepancy between air quality simulations obtained with a climate model or with meteorological reanalyses is pointed out. Sensitivity simulations show that the main factor driving future air quality projections is air pollutant emissions, rather than climate change or intercontinental transport of pollution. Whereas the well documented "climate penalty" that weights upon ozone (increase of ozone pollution with global warming over Europe is confirmed, other features appear less robust compared to the literature, such as the impact of climate on PM2.5. The quantitative disentangling of external factors shows that, while several published studies focused on the climate penalty bearing upon ozone, the contribution of the global ozone burden is somewhat overlooked in the literature.

  18. Safety Analysis Results for Cryostat Ingress Accidents in ITER

    Science.gov (United States)

    Merrill, B. J.; Cadwallader, L. C.; Petti, D. A.

    1997-06-01

    Accidents involving the ingress of air, helium, or water into the cryostat of the International Thermonuclear Experimental Reactor (ITER) tokamak design have been analyzed with a modified version of the MELCOR code for the ITER Non-site Specific Safety Report (NSSR-1). The air ingress accident is the result of a postulated breach of the cryostat boundary into an adjoining room. MELCOR results for this accident demonstrate that the condensed air mass and increased heat loads are not a magnet safety concern, but that the partial vacuum in the adjoining room must be accommodated in the building design. The water ingress accident is the result of a postulated magnet arc that results in melting of a Primary Heat Transport System (PHTS) coolant pipe, discharging PHTS water and PHTS water activated corrosion products and HTO into the cryostat. MELCOR results for this accident demonstrate that the condensed water mass and increased heat loads are not a magnet safety concern, that the cryostat pressure remains below design limits, and that the corrosion product and HTO releases are well within the ITER release limits.

  19. Chloride ingress in cement paste and mortar

    DEFF Research Database (Denmark)

    Jensen, Ole Mejlhede; Hansen, Per Freiesleben; Coats, Alison M.; Glasser, Fred P.

    1999-01-01

    In this paper chloride ingress in cement paste and mortar is followed by electron probe microanalysis. The influence of several paste and exposure parameters on chloride ingress are examined (e.g., water-cement ratio, silica fume addition, exposure time, and temperature), The measurements are...

  20. European atmosphere in 2050, a regional air quality and climate perspective under CMIP5 scenarios

    OpenAIRE

    Colette, A.; Bessagnet, B.; R. Vautard; Szopa, S.; Rao, S; Schucht, S.; Z. Klimont; L. Menut; G. Clain; Meleux, F.; Curci, G.; L. Rouïl

    2013-01-01

    To quantify changes in air pollution over Europe at the 2050 horizon, we designed a comprehensive modelling system that captures the external factors considered to be most relevant, and that relies on up-to-date and consistent sets of air pollution and climate policy scenarios. Global and regional climate as well as global chemistry simulations are based on the recent representative concentration pathways (RCP) produced for the Fifth Assessment Report (AR5) of the IPCC (Intergovernmental Pane...

  1. Witwatersrand Water Ingress Project - Information Management System (WWIPIMS), South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Hild, S.; Sieste, M.; Barth, A.; Rudinskaya, J. [Beak Consultants GmbH, Freiberg (Germany); Croukamp, L.; Roos, M. [Council for Geoscience (CGS), Pretoria (South Africa)

    2006-07-01

    The Witwatersrand Water Ingress Project at the Council for Geoscience, South Africa (CGS) deals with an inventory, a risk assessment and the development of rehabilitation strategies for abandoned mining sites in the Witwatersrand Mining Basin. The main focus is the prevention of water ingress and to understand the future decanting scenario. An Information Management System consisting of both a relational database and an application for the Witwatersrand Water Ingress Project is established for accessing and managing all project-related data. This easy to use application makes the data available to all staff at the CGS via several modules as well as a GIS-component for accessing and querying spatial data. This will enable the scientists to derive further knowledge of the water flowing processes by directly using all of the existing up-to-date data. Many additional functions, such as the support for map printing on demand, extensive possibilities for inquiries, data import and export, diagrams and a GIS-viewer for spatial inquiries do complete the system. (orig.)

  2. Large Gain in Air Quality Compared to an Alternative Anthropogenic Emissions Scenario

    Science.gov (United States)

    Daskalakis, Nikos; Tsigaridis, Kostas; Myriokefalitakis, Stelios; Fanourgakis, George S.; Kanakidou, Maria

    2016-01-01

    During the last 30 years, significant effort has been made to improve air quality through legislation for emissions reduction. Global three-dimensional chemistrytransport simulations of atmospheric composition over the past 3 decades have been performed to estimate what the air quality levels would have been under a scenario of stagnation of anthropogenic emissions per capita as in 1980, accounting for the population increase (BA1980) or using the standard practice of neglecting it (AE1980), and how they compare to the historical changes in air quality levels. The simulations are based on assimilated meteorology to account for the yearto- year observed climate variability and on different scenarios of anthropogenic emissions of pollutants. The ACCMIP historical emissions dataset is used as the starting point. Our sensitivity simulations provide clear indications that air quality legislation and technology developments have limited the rapid increase of air pollutants. The achieved reductions in concentrations of nitrogen oxides, carbon monoxide, black carbon, and sulfate aerosols are found to be significant when comparing to both BA1980 and AE1980 simulations that neglect any measures applied for the protection of the environment. We also show the potentially large tropospheric air quality benefit from the development of cleaner technology used by the growing global population. These 30-year hindcast sensitivity simulations demonstrate that the actual benefit in air quality due to air pollution legislation and technological advances is higher than the gain calculated by a simple comparison against a constant anthropogenic emissions simulation, as is usually done. Our results also indicate that over China and India the beneficial technological advances for the air quality may have been masked by the explosive increase in local population and the disproportional increase in energy demand partially due to the globalization of the economy.

  3. Large gain in air quality compared to an alternative anthropogenic emissions scenario

    Science.gov (United States)

    Daskalakis, Nikos; Tsigaridis, Kostas; Myriokefalitakis, Stelios; Fanourgakis, George S.; Kanakidou, Maria

    2016-08-01

    During the last 30 years, significant effort has been made to improve air quality through legislation for emissions reduction. Global three-dimensional chemistry-transport simulations of atmospheric composition over the past 3 decades have been performed to estimate what the air quality levels would have been under a scenario of stagnation of anthropogenic emissions per capita as in 1980, accounting for the population increase (BA1980) or using the standard practice of neglecting it (AE1980), and how they compare to the historical changes in air quality levels. The simulations are based on assimilated meteorology to account for the year-to-year observed climate variability and on different scenarios of anthropogenic emissions of pollutants. The ACCMIP historical emissions dataset is used as the starting point. Our sensitivity simulations provide clear indications that air quality legislation and technology developments have limited the rapid increase of air pollutants. The achieved reductions in concentrations of nitrogen oxides, carbon monoxide, black carbon, and sulfate aerosols are found to be significant when comparing to both BA1980 and AE1980 simulations that neglect any measures applied for the protection of the environment. We also show the potentially large tropospheric air quality benefit from the development of cleaner technology used by the growing global population. These 30-year hindcast sensitivity simulations demonstrate that the actual benefit in air quality due to air pollution legislation and technological advances is higher than the gain calculated by a simple comparison against a constant anthropogenic emissions simulation, as is usually done. Our results also indicate that over China and India the beneficial technological advances for the air quality may have been masked by the explosive increase in local population and the disproportional increase in energy demand partially due to the globalization of the economy.

  4. Evaluation of pressure response in the Los Alamos controlled air incinerator during three incident scenarios

    International Nuclear Information System (INIS)

    The Los Alamos Controlled Air Incinerator (CAI) is a system designed to accept radioactive mixed waste containing alpha-emitting radionuclides. A mathematical model was developed to predict the pressure response throughout the offgas treatment system of the CAI during three hypothetical incident scenarios. The scenarios examined included: (1) loss of burner flame and failure of the flame safeguard system with subsequent reignition of fuel gas in the primary chamber, (2) pyrolytic gas buildup from a waste package due to loss of induced draft and subsequent restoration of induced draft, and (3) accidental charging of propellant spray cans in a solid waste package to the primary chamber during a normal feed cycle. For each of the three scenarios, the finite element computer model was able to determine the transient pressure surge and decay response throughout the system. Of particular interest were the maximum absolute pressures attainable at critical points in the system as well as maximum differential pressures across the high efficiency particulate air (HEPA) filters. Modeling results indicated that all three of the scenarios resulted in maximum HEPA filter differential pressures well below the maximum allowable levels

  5. Finnish air traffic until 2025. Four scenarios; Suomen lentoliikenne vuoteen 2025 - neljae skenaariota

    Energy Technology Data Exchange (ETDEWEB)

    Aalto, E.; Pollanen, M.; Mantynen, J.; Makela, T.; Rauhamaki, H. [Tampere Univ. of Technology (Finland). Transport Research Centre Verne

    2012-07-01

    Air traffic is a very dynamic field of business. Its operating environment features multiple factors of change, which affect air traffic and its operators both in the short and in the long run. This study charts the significant factors in Finnish air traffic and creates four distinct scenarios for the future. These scenarios were produced on the basis of the currently available facts and are attempts to provide several alternatives for the future. The study's goal has been to produce a visionary depiction that helps one to visualise and understand the whole picture. The perspective chosen for consideration of the future is the year 2025. The study describes four scenarios differing clearly from each other. In the first, entitled Globaalista maailmasta blokkeihin (From a global world to blocs), states form clusters and regional co-operation takes precedence over the current global direction of development. The second, Eurooppa omalla reitillaeaen (Europe on its own way), depicts Europe ahead of the rest of the world in terms of environmental regulation for air traffic. Uudistuksilla talouskukoistukseen (Economic boom through reforms) is based on an optimistic economic outlook. In contrast, Oeljykriisistae taloustaantumaan (From oil crisis to recession), describes a world where economic growth has been forestalled by rising oil prices due to increasing scarcity. The study investigates passenger numbers, air traffic within Finland, the international route network, and the changes these display in the various scenarios. The estimates are designed to highlight the development trends affecting air traffic in different operating environments. Since Finland is a small country and set apart from the rest of Europe in a fashion similar to island states, air traffic is of major importance and cannot be efficiently replaced by other forms of traffic. In particular, the individual scenarios stress the impact of international interaction and economic development with regard

  6. Climate and air quality-driven scenarios of ozone and aerosol precursor abatement

    International Nuclear Information System (INIS)

    In addition to causing domestic and regional environmental effects, many air pollutants contribute to radiative forcing (RF) of the climate system. However, climate effects are not considered when cost-effective abatement targets for these pollutants are established, nor are they included in current international climate agreements. We construct air pollution abatement scenarios in 2030 which target cost-effective reductions in RF in the EU, USA, and China and compare these to abatement scenarios which instead target regional ozone effects and particulate matter concentrations. Our analysis covers emissions of PM (fine, black carbon and organic carbon), SO2, NOx, CH4, VOCs, and CO. We find that the effect synergies are strong for PM/BC, VOC, CO and CH4. While an air quality strategy targeted at reducing ozone will also reduce RF, this will not be the case for a strategy targeting particulate matter. Abatement in China dominates RF reduction, but there are cheap abatement options also available in the EU and USA. The justification for international cooperation on air quality issues is underlined when the co-benefits of reduced RF are considered. Some species, most importantly SO2, contribute a negative forcing on climate. We suggest that given current knowledge, NOx and SO2 should be ignored in RF-targeted abatement policies.

  7. Ship emissions and air pollution in Denmark. Present situation and future scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Roerdam Olesen, H.; Winther, M.; Ellermann, T.; Christensen, Jesper; Plejdrup, M. (Aarhus Univ., National Environmental Research Institute, Aarhus (Denmark))

    2009-07-01

    Ship traffic in the Danish marine waters is considered to be important for air quality in Danish cities and in Denmark in general. Since 2006 the so-called Automatic Identification System (AIS) has registered ship activities in Danish marine waters. All ships larger than 300 GT (Gross Tonnage) are required to carry a transponder, which transmits information on the ship's identity and position to land-based receiving stations. This information makes it possible to map ship emissions in much greater detail than previously feasible. This opportunity has now been utilised to create a new emission inventory for ships in the Danish marine waters. A main objective of this work is to assess the contribution from ships to concentration levels of various pollutants. For the modelling of concentrations, a new version of the air pollution model DEHM (Danish Eulerian Hemispheric Model) has been applied - a version with a higher geographical resolution than the previous version. The International Maritime Organisation (IMO) has adopted new regulations in order to reduce pollution from ships with sulphur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub X}) in the period until 2020. It is also the objective of this work to investigate the effect of this regulation on air quality in Denmark. This is done through scenario calculations for air quality for 2020 based on expected emission reductions. Also for land-based sources of SO{sub 2}, NO{sub x} and particles, emission reductions are envisaged before 2020. The scenario calculation for 2020 takes account of these reductions. As one of the main parts of the study a new, improved inventory of ship emissions in the Danish marine waters has been established. Both new (NERI) and old (EMEP, 2008) emission inventories have been applied for model calculations of air quality in Denmark, thus allowing an assessment of the effect of the revised inventory. Furthermore, scenario calculations for 2011 and 2020 have been carried out, in

  8. Googles Augmented-Reality-Game "Ingress"

    Directory of Open Access Journals (Sweden)

    Karl H. Stingeder

    2013-12-01

    Full Text Available Das an das "Geocoaching"-Spielprinzip erinnernde Augmented-­Reality-Game "Ingress" ist auf allen mit Android-Betriebssystem ausgestatteten Smartphones spielbar. Das Alleinstellungsmerkmal des Spiels ist gleich­zeitig auch das beste Patent-Rezept für bzw. gegen notorisches "Couch-Potato-ing": Das Game-Design des "Draußenspiels" erfordert jedoch stets die physische Anwesenheit der SpielerInnen am realen Ort des Geschehens, meist touristisch attraktive Sehenswürdigkeiten und architektonisch markante Plätze. Sobald "Ingress" per App am Smart­phone gestartet wird, stehen Interaktionen und Machtverhältnisse auf dem Handy-Display im Dreh- und Angelpunkt des Geschehens. Die Spielgrafik ist auf das Wesentliche reduziert und erinnert an die Optik von Videospielen der 80er Jahre. "Ingress" im Allgemeinen sowie "Magnus13", die erste von Google organisierte Fan-Veranstaltung Österreichs mit mehreren Hundert TeilnehmerInnen und ist mit einer "digitalen Schnitzeljagd" vergleichbar: Gemeinsam ist der klassischen "Schnitzeljagd" und dem digitalen "Schere-Schein-Papier" Prinzip von "Ingress" die tragende Rolle des im Spiel entstehenden Gemeinschaftsgefühls, welche in einer hohen Langzeitmotivation mündet. Trotz aller Euphorie, ob des unkonventionellen Augmented-Reality-Spielkonzepts und des in Folge der sozialen Dynamik außergewöhnlichen Sucht­potentials, ist angesichts von Edward Snowden und vielfältiger NSA-Abhörmaßnahmen, eine gesunde Portion Skepsis angebracht: Welchen Zweck erfüllt "Ingress"? Gibt es ein verhülltes "Mittel zum Zweck"? Welche Gefahren bestehen mit einer systematischen Auswertung des umfangreichen, ortsrelevanten Daten-Sammelsuriums? "Ingress" verdeutlicht trotz aller Risiken den soziokulturellen Bedeutungswandel des digitalen Spiels: Spiele per se und das Spiel als soziale Interaktion sind aktuell dabei, alle Bereiche unseres Lebens zu erfassen.

  9. Emissions inventory and scenario analyses of air pollutants in Guangdong Province, China

    Science.gov (United States)

    Chen, Hui; Meng, Jing

    2016-03-01

    Air pollution, causing significantly adverse health impacts and severe environmental problems, has raised great concerns in China in the past few decades. Guangdong Province faces major challenges to address the regional air pollution problem due to the lack of an emissions inventory. To fill this gap, an emissions inventory of primary fine particles (PM2.5) is compiled for the year 2012, and the key precursors (sulfur dioxide, nitrogen oxides) are identified. Furthermore, policy packages are simulated during the period of 2012-2030 to investigate the potential mitigation effect. The results show that in 2012, SO2, NO x , and PM2.5 emissions in Guangdong Province were as high as (951.7, 1363.6, and 294.9) kt, respectively. Industrial production processes are the largest source of SO2 and PM2.5 emissions, and transport is the top contributor of NO x emissions. Both the baseline scenario and policy scenario are constructed based on projected energy growth and policy designs. Under the baseline scenario, SO2, NO x , and PM2.5 emissions will almost double in 2030 without proper emissions control policies. The suggested policies are categorized into end-of-pipe control in power plants (ECP), end-of-pipe control in industrial processes (ECI), fuel improvement (FI), energy efficiency improvement (EEI), substitution-pattern development (SPD), and energy saving options (ESO). With the implementation of all these policies, SO2, NO x , and PM2.5 emissions are projected to drop to (303.1, 585.4, and 102.4) kt, respectively, in 2030. This inventory and simulated results will provide deeper insights for policy makers to understand the present situation and the evolution of key emissions in Guangdong Province.

  10. Air emissions scenarios from ethanol as a gasoline oxygenate in Mexico City Metropolitan Area

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Carlos A. [Posgrado en Ingenieria Energetica, Universidad Nacional Autonoma de Mexico, Priv. Xochicalco s/n, Col. Centro, Apartado Postal 34, 62580 Temixco, Morelos (Mexico); Manzini, Fabio; Islas, Jorge [Centro de Investigacion en Energia, Universidad Nacional Autonoma de Mexico, Priv. Xochicalco s/n, Col. Centro, Apartado Postal 34, 62580 Temixco, Morelos (Mexico)

    2010-12-15

    The Mexican Biofuel Introduction Program states that during year 2010 the three biggest Mexican cities will have a gasoline blending with 6% ethanol available for all gasoline on-road vehicle fleet. Also in 2010 Mexican government has programmed to start the substitution of Tier 1 - the adopted US emission standards - by Tier 2, which are more stringent emission standards for motor vehicles and gasoline sulfur control requirements. How will the air emissions in the Mexico City Metropolitan Area (MCMA) be modified by using this blending? Four scenarios up to year 2030 were constructed and simulated using the Long-Range Energy Alternatives Planning model. Beginning with a BAU or reference scenario, in this scenario the current available fuel is a blending composed by 5% methyl tertiary butyl ether and 95% gasoline (MTBE5). Then, three alternative scenarios that use ethanol as an oxygenate are considered, one with the already programmed E6 blending (6% anhydride ethanol, 94% gasoline), for the sake of comparison the E10 blending (10% anhydride ethanol, 90% gasoline), and the other alternative to compare, ETBE13.7 (13.7% ethyl tertiary butyl ether, 86.3% gasoline; where ETBE is an ether composed by 48% anhydride ethanol and 52% isobutene). Emissions of carbon dioxide (CO{sub 2}), carbon monoxide (CO), nitrogen oxides (NOx), particulate matter (PM10), sulfur dioxide (SO{sub 2}), total hydrocarbons (THC), benzene, formaldehyde, acetaldehyde and 1,3-butadiene were calculated using emission factors previously calculated using the adapted US-EPA computer model called MOBILE6-Mexico. Results show that Tier 1 and Tier 2 standards effectively lowers all emissions in all studied scenarios with the exception of PM10 and CO{sub 2} emissions. The alternative scenario E10 has the most total avoided emissions by weight but it is not the best when considering some individual pollutants. The greatest environmental benefit of ethanol in its final use as a gasoline oxygenate is for

  11. Chloride ingress in cement paste and mortar

    DEFF Research Database (Denmark)

    Jensen, Ole Mejlhede; Hansen, Per Freiesleben; Coats, Alison M.;

    1999-01-01

    modelled on Fick's law modified by a term for chloride binding. Inclusion of chloride binding significantly improves the profile shape of the modelled ingress profiles. The presence of fine aggregate and formation of interfacial transition zones at paste-aggregate boundaries does not significantly affect...

  12. Assessment of NGNP Moisture Ingress Events

    Energy Technology Data Exchange (ETDEWEB)

    Bill Landman

    2011-04-01

    An assessment of modular HTGR moisture ingress events, making use of a phenomena identification and ranking process, was conducted by a panel of experts in the related areas for the U.S. next generation nuclear plant (NGNP) design. Consideration was given mainly to the prismatic core gas-cooled reactor configurations incorporating a steam generator within the primary circuit.

  13. Modeled effects of an improved building insulation scenario in Europe on air pollution, health and societal costs

    DEFF Research Database (Denmark)

    Bønløkke, Jakob Hjort; Holst, Gitte Juel; Sigsgaard, Torben;

    2015-01-01

    insulation scenario in Europe would have substantial benefits on health through improvements in air pollution. Health effects and societal cost savings may significantly counterbalance investment costs and should be taken into account when evaluating strategies for mitigation of global warming....... the resulting effects on health and economy. Methods: Projected energy savings between 2005 and 2020 were calculated for an improved building insulation scenario and a business as usual scenario. The resulting changes in emissions (e.g. from power plants) were used in the Comprehensive Air......-Quality Model with extensions. Mean annual changes in the main air pollutants were derived for each country. World Health Organization (WHO) and European Union (EU) data on populations and on impacts of pollutants were used to derive health effects and costs. Effects on indoor air quality were not assessed...

  14. An Empirically grounded Agent Based simulator for the Air Traffic Management in the SESAR scenario

    CERN Document Server

    Gurtner, Gérald; Ducci, Marco; Miccichè, Salvatore

    2016-01-01

    In this paper we present a simulator allowing to perform policy experiments relative to the air traffic management. Different SESAR solutions can be implemented in the model to see the reaction of the different stakeholders as well as other relevant metrics (delays, safety, etc). The model describes both the strategic phase associated to the planning of the flight trajectories and the tactical modifications occurring in the en-route phase. An implementation of the model is available as open-source and freely accessible by any user. More specifically, different procedures related to business trajectories and free-routing are tested and we illustrate the capabilities of the model on airspace implementing these concepts. After performing numerical simulations with the model, we show that in a free-routing scenario the controllers perform less operations although they are dispersed over a larger portion of the airspace. This can potentially increase the complexity of conflict detection and resolution for controll...

  15. Evaluation of the 2006 Canadian Air Quality Modelling Platform for Policy Scenarios

    Science.gov (United States)

    Davignon, D.; Chen, J.; Cousineau, S.; Crevier, L.; Duhamel, A.; Gilbert, S.; Pavlovic, R.; Racine, J.; Samaali, M.; Sassi, M.

    2009-12-01

    A modelling platform for the purposes of air quality policy scenario assessments is being setup and evaluated at Environment Canada. The main modelling system within the platform is the Environment Canada AURAMS (A Unified Regional Air quality Modelling System) which has explicit treatments of gaseous and particulate matter chemistry and physics. Additional components of the platform include the Global Environmental Model (GEM) for meteorology, the Sparse Matrix Operating Kernel Emissions (SMOKE) processing system, and a set of tools and models to diagnose and bridge results for health benefit and environmental impact analyses. In order to capture the seasonality and the distributions of the atmospheric conditions at different regions in Canada, the platform is applied for an annual simulation with a large domain encompassing the North American continent at 45-km grid resolution. The coarse resolution results are then refined with two nested domains for the east and west Canada at 22.5-km grid resolution. To evaluate of the modelling platform, the annual simulation results for 2006 are compared against ambient measurements for ozone and PM2.5. Measurement data are from both routine observational networks in Canada and United States (NAPS, IMPROVE, AQS), as well as non-routine measurement campaigns in 2006, which include vertical ozone profiles at selected locations in the domain. The presentation provides an overview of the current modelling platform setup and configurations, as well as discussions on the preliminary evaluation results from the annual simulations.

  16. Investigation of sodium-mineral oil interaction in the experiments, modeling oil ingress phenomena on PFR

    International Nuclear Information System (INIS)

    This report contains a brief description of the experimental investigations made in June 1991 at the sodium installation of IPPE, Obninsk, with regard to the conditions of the proposed scenarios of oil ingress into PFR primary circuit. In particular, the report presents experimental results of investigations of PFR S/A inlet filter behaviour after oil injection into the sodium circuit at different conditions and relevant aspects of the oil-sodium system evolution. (author)

  17. The study on water ingress mass in the steam generator heat-exchange tube rupture accident of modular high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    The steam generator heat-exchange tube rupture (SGTR) accident is an important and particular accident which will result in water ingress to the primary loop of reactor. Water ingress will result in chemical reaction of graphite fuel and structure with water, which may cause overpressure due to generation of explosive gaseous in large quantity. The study on the water ingress accident is significant for the verification of the inherent characteristics of high temperature gas-cooled reactor. The previous research shows that the amount of water ingress mass is the dominant key factor on the severity of the accident consequence. The 200 MWe high temperature gas-cooled reactor (HTR-PM), which is the first modular pebble-bed high temperature gas-cooled reactor in China designed by the Institute of Nuclear and New Energy Technology of Tsinghua University, is selected to be analyzed in this paper. The different DBA accident scenarios of double-ended break of single heat-exchange tube are simulated respectively by the thermal-hydraulic analysis code RETRAN-02. The results show the water ingress mass through the broken heat-exchange tube is related to the break location. The amount of water ingress mass is affected obviously by the capacity of the emptier system. With the balance of safety and economical efficiency, the amount of water ingress mass from the secondary side of steam generator into the primary coolant loop will be reduced by increasing properly the diameter of the draining lines. (authors)

  18. Information from water ingress accident on AVR

    International Nuclear Information System (INIS)

    An ingress of water occurred in the AVR reactor in May 1978. The reactor had been shut down and cooled by forced circulation; liquid water entered the primary circuit from a leak in the superheater, evaporated in passing through the core and condensed in the lower part of the primary circuit and in the ball handling region. Various fission product activities were measured in the water by the AVR scientists and a study was started to identify the sources of these activities and to derive information which could be used in the analyses of water ingress accidents in general. The first part of this study is reported in this note. The possible source terms are considered separately and estimates of their contributions are made, supported by data from previous laboratory experiments where possible. The main conclusion is that valuable information has been derived concerning the desorption of iodine, cesium and strontium from dust and primary circuit surfaces. A minimum programme of measurements and analytical work necessary to increase this information has been identified. An example of the application of the data to a particular accident to a power reactor is given to indicate how the information can affect the calculation of consequences. For the second part of the study, better estimates of the fission product concentrations in the primary circuit prior to the accident and various measurements when the reactor is operating again are required. (orig.)

  19. Chloride Ingress in Concrete Cracks under Cyclic Loading

    DEFF Research Database (Denmark)

    Küter, André; Geiker, Mette Rica; Olesen, John Forbes;

    2005-01-01

    increasing focus on the need for modeling the ingress of chloride into cracked concrete. Present models quantify chloride ingress in static cracks only, although several structural applications display dynamic loading conditions in an environment containing chlorides, e.g. marine structures and car parks....... Preliminary investigations have been undertaken to quantify the effect of dynamic load application on the chloride ingress into concrete cracks. Specimens were designed allowing ingress of a chloride solution into a single crack of a saturated unreinforced mortar beam. One set of specimens was subjected to a...... load frequency of ten applications per minute and a second set to one application per hour simulating static cracks, however limiting the ingress hampering effects of autogenous healing and a possible dense precipitation on the crack faces. The averaged chloride exposure interval of the crack faces was...

  20. Short-term impacts of air pollutants in Switzerland: Preliminary scenario calculations for selected Swiss energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Andreani-Aksoyoglu, S.; Keller, J. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    In the frame of the comprehensive assessment of Swiss energy systems, air quality simulations were performed by using a 3-dimensional photo-chemical dispersion model. The objective is to investigate the impacts of pollutants in Switzerland for future options of Swiss energy systems. Four scenarios were investigated: Base Case: simulations with the projected emissions for the year 2030, Scenario 1) all nuclear power plants were replaced by oil-driven combined cycle plants (CCP), Scenarios 2 to 4) traffic emissions were reduced in whole Switzerland as well as in the cities and on the highways separately. Changes in the pollutant concentrations and depositions, and the possible short-term impacts are discussed on the basis of exceedences of critical levels for plants and limits given to protect the public health. (author) 2 figs., 7 refs.

  1. Air quality impacts of plug-in hybrid electric vehicles in Texas: evaluating three battery charging scenarios

    International Nuclear Information System (INIS)

    The air quality impacts of replacing approximately 20% of the gasoline-powered light duty vehicle miles traveled (VMT) with electric VMT by the year 2018 were examined for four major cities in Texas: Dallas/Ft Worth, Houston, Austin, and San Antonio. Plug-in hybrid electric vehicle (PHEV) charging was assumed to occur on the electric grid controlled by the Electricity Reliability Council of Texas (ERCOT), and three charging scenarios were examined: nighttime charging, charging to maximize battery life, and charging to maximize driver convenience. A subset of electricity generating units (EGUs) in Texas that were found to contribute the majority of the electricity generation needed to charge PHEVs at the times of day associated with each scenario was modeled using a regional photochemical model (CAMx). The net impacts of the PHEVs on the emissions of precursors to the formation of ozone included an increase in NOx emissions from EGUs during times of day when the vehicle is charging, and a decrease in NOx from mobile emissions. The changes in maximum daily 8 h ozone concentrations and average exposure potential at twelve air quality monitors in Texas were predicted on the basis of these changes in NOx emissions. For all scenarios, at all monitors, the impact of changes in vehicular emissions, rather than EGU emissions, dominated the ozone impact. In general, PHEVs lead to an increase in ozone during nighttime hours (due to decreased scavenging from both vehicles and EGU stacks) and a decrease in ozone during daytime hours. A few monitors showed a larger increase in ozone for the convenience charging scenario versus the other two scenarios. Additionally, cumulative ozone exposure results indicate that nighttime charging is most likely to reduce a measure of ozone exposure potential versus the other two scenarios.

  2. Links between atmospheric circulation and surface air temperature in climate models in control climate and future scenarios

    Czech Academy of Sciences Publication Activity Database

    Plavcová, Eva; Kyselý, Jan

    Bern: Swiss Climate Research, 2011, s. 84-85. [International NCCR Climate Summer School "Climate Change, Extremes and Ecosystem Services" /10./. Grindelwald (CH), 04.09.2001-09.09.2011] R&D Projects: GA ČR GAP209/10/2265 Institutional research plan: CEZ:AV0Z30420517 Keywords : regional climate models * air temperature * atmospheric circulation * future climate change scenarios Subject RIV: DG - Athmosphere Sciences, Meteorology

  3. Development of a Prototype Automation Simulation Scenario Generator for Air Traffic Management Software Simulations

    Science.gov (United States)

    Khambatta, Cyrus F.

    2007-01-01

    A technique for automated development of scenarios for use in the Multi-Center Traffic Management Advisor (McTMA) software simulations is described. The resulting software is designed and implemented to automate the generation of simulation scenarios with the intent of reducing the time it currently takes using an observational approach. The software program is effective in achieving this goal. The scenarios created for use in the McTMA simulations are based on data taken from data files from the McTMA system, and were manually edited before incorporation into the simulations to ensure accuracy. Despite the software s overall favorable performance, several key software issues are identified. Proposed solutions to these issues are discussed. Future enhancements to the scenario generator software may address the limitations identified in this paper.

  4. Modeling moisture ingress through simplified concrete crack geometries

    DEFF Research Database (Denmark)

    Pease, Bradley Justin; Michel, Alexander; Geiker, Mette Rica; Stang, Henrik

    2011-01-01

    This paper introduces a numerical model for ingress in cracked steel fibre reinforced concrete. Details of a simplified crack are preset in the model’s geometry using the cracked hinge model (CHM). The total crack length estimated using the CHM was, based on earlier work on conventional concrete......, considered to have two parts; 1) a coalesced crack length which behaves as a free-surface for moisture ingress, and 2) an isolated microcracking length which resists ingress similarly to the bulk material. Transport model results are compared to experimental results from steel fibre reinforced concrete wedge...

  5. The impact of China's vehicle emissions on regional air quality in 2000 and 2020: a scenario analysis

    Directory of Open Access Journals (Sweden)

    E. Saikawa

    2011-09-01

    Full Text Available The number of vehicles in China has been increasing rapidly. We evaluate the impact of current and possible future vehicle emissions from China on Asian air quality. We modify the Regional Emission Inventory in Asia (REAS for China's road transport sector in 2000 using updated Chinese data for the number of vehicles, annual mileage, and emission factors. We develop two scenarios for 2020: a scenario where emission factors remain the same as they were in 2000 (No-Policy, NoPol, and a scenario where Euro 3 vehicle emission standards are applied to all vehicles (except motorcycles and rural vehicles. The Euro 3 scenario is an approximation of what may be the case in 2020 as, starting in 2008, all new vehicles in China (except motorcycles were required to meet the Euro 3 emission standards. Using the Weather Research and Forecasting model coupled with Chemistry (WRF/Chem, we examine the regional air quality response to China's vehicle emissions in 2000 and in 2020 for the NoPol and Euro 3 scenarios. We evaluate the 2000 model results with observations in Japan, China, Korea, and Russia. Under NoPol in 2020, emissions of carbon monoxide (CO, nitrogen oxides (NOx, non-methane volatile organic compounds (NMVOCs, black carbon (BC, and organic carbon (OC from China's vehicles more than double compared to the 2000 baseline. If all vehicles meet the Euro 3 regulations in 2020, however, these emissions are reduced by more than 50% relative to NoPol. The implementation of stringent vehicle emission standards leads to a large, simultaneous reduction of the surface ozone (O3 mixing ratios and particulate matter (PM2.5 concentrations. In the Euro 3 scenario, surface O3 is reduced by more than 10 ppbv and surface PM2.5 is reduced by more than 10 μg m−3 relative to NoPol in Northeast China in all seasons. In spring, surface O3 mixing ratios and PM2.5 concentrations in

  6. Modeling Effects of Climate Change on Air Quality and Population Exposure in Urban Planning Scenarios

    Directory of Open Access Journals (Sweden)

    Lars Gidhagen

    2012-01-01

    Full Text Available We employ a nested system of global and regional climate models, linked to regional and urban air quality chemical transport models utilizing detailed inventories of present and future emissions, to study the relative impact of climate change and changing air pollutant emissions on air quality and population exposure in Stockholm, Sweden. We show that climate change only marginally affects air quality over the 20-year period studied. An exposure assessment reveals that the population of Stockholm can expect considerably lower NO2 exposure in the future, mainly due to reduced local NOx emissions. Ozone exposure will decrease only slightly, due to a combination of increased concentrations in the city centre and decreasing concentrations in the suburban areas. The increase in ozone concentration is a consequence of decreased local NOx emissions, which reduces the titration of the long-range transported ozone. Finally, we evaluate the consequences of a planned road transit project on future air quality in Stockholm. The construction of a very large bypass road (including one of the largest motorway road tunnels in Europe will only marginally influence total population exposure, this since the improved air quality in the city centre will be complemented by deteriorated air quality in suburban, residential areas.

  7. Changes in future air quality, deposition, and aerosol-cloud interactions under future climate and emission scenarios

    Science.gov (United States)

    Glotfelty, Timothy; Zhang, Yang; Karamchandani, Prakash; Streets, David G.

    2016-08-01

    The prospect of global climate change will have wide scale impacts, such as ecological stress and human health hazards. One aspect of concern is future changes in air quality that will result from changes in both meteorological forcing and air pollutant emissions. In this study, the GU-WRF/Chem model is employed to simulate the impact of changing climate and emissions following the IPCC AR4 SRES A1B scenario. An average of 4 future years (2020, 2030, 2040, and 2050) is compared against an average of 2 current years (2001 and 2010). Under this scenario, by the Mid-21st century global air quality is projected to degrade with a global average increase of 2.5 ppb in the maximum 8-hr O3 level and of 0.3 μg m-3 in 24-hr average PM2.5. However, PM2.5 changes are more regional due to regional variations in primary aerosol emissions and emissions of gaseous precursor for secondary PM2.5. Increasing NOx emissions in this scenario combines with a wetter climate elevating levels of OH, HO2, H2O2, and the nitrate radical and increasing the atmosphere's near surface oxidation state. This differs from findings under the RCP scenarios that experience declines in OH from reduced NOx emissions, stratospheric recovery of O3, and increases in CH4 and VOCs. Increasing NOx and O3 levels enhances the nitrogen and O3 deposition, indicating potentially enhanced crop damage and ecosystem stress under this scenario. The enhanced global aerosol level results in enhancements in aerosol optical depth, cloud droplet number concentration, and cloud optical thickness. This leads to dimming at the Earth's surface with a global average reduction in shortwave radiation of 1.2 W m-2. This enhanced dimming leads to a more moderate warming trend and different trends in radiation than those found in NCAR's CCSM simulation, which does not include the advanced chemistry and aerosol treatment of GU-WRF/Chem and cannot simulate the impacts of changing climate and emissions with the same level of detailed

  8. Engineering Strategies and Methods for Avoiding Air-Quality Externalities: Dispersion Modeling, Home Energy Conservation, and Scenario Planning

    Science.gov (United States)

    Knox, Andrew James

    Energy conservation can improve air quality by reducing emissions from fuel combustion. The human health value retained through better air quality can then offset the cost of energy conservation. Through this thesis' innovative yet widely-accessible combination of air pollution dispersion modeling and atmospheric chemistry, it is estimated that the health value retained by avoiding emissions from Ontario's former coal-fired generating stations is 5.74/MWh (using an upper-bound value of 265,000 per year of life lost). This value is combined with energy modeling of homes in the first-ever assessment of the air-quality health benefits of low-energy buildings. It is shown that avoided health damages can equal 7% of additional construction costs of energy efficient buildings in Ontario. At 7%, health savings are a significant item in the cost analysis of efficient buildings. Looking to energy efficiency in the context of likely future low-resource natural gas scenarios, building efficient buildings today is shown to be more economically efficient than any building retrofit option. Considering future natural gas scarcity in the context of Ontario's Long-Term Energy Plan reveals that Ontario may be forced to return to coal-fired electricity. Projected coal use would result in externalities greater than $600 million/year; 80% more than air-quality externalities from Ontario's electricity in 1985. Radically aggressive investment in electricity conservation (75% reduction per capita by 2075) is one promising path forward that keeps air-quality externalities below 1985 levels. Non-health externalities are an additional concern, the quantification, and ultimately monetization, of which could be practical using emerging air pollution monitoring technologies. Energy, conservation, energy planning, and energy's externalities form a complex situation in which today's decisions are critical to a successful future. It is clear that reducing the demand for energy is essential and

  9. Emission scenarios for a global hydrogen economy and the consequences for global air pollution

    NARCIS (Netherlands)

    van Ruijven, B.J.; Lamarque, J.F.; van Vuuren, D.P.; Kram, T.; Eerens, H.

    2011-01-01

    Hydrogen is named as possible energy carrier for future energy systems. However, the impact of large-scale hydrogen use on the atmosphere is uncertain. Application of hydrogen in clean fuel cells reduces emissions of air pollutants, but emissions from hydrogen production and leakages of molecular hy

  10. Scenarios for the Future of Air Quality: Planning and Analysis in an Uncertain World

    Science.gov (United States)

    On November 15 and 16 of 2010, EPA hosted a workshop: The Future of Air Quality: Planning and Analysis in An Uncertain World in Chapel Hill, North Carolina. This workshop was an “outside-of-the-box” thinking exercise, where a small group of EPA staff and managers brainstormed o...

  11. A Life Cycle Assessment of the Passenger Air Transport System Using Three Flight Scenarios

    OpenAIRE

    Lewis, Tyler

    2013-01-01

    The commercial aviation industry is drawing more and more attention from governments, international organizations and industry stakeholders as calls for improved environmental performance escalate and global concern to mitigate the production of greenhouse gas (GHG) emissions increases. International demand for commercial air transport is projected to steadily grow at a rate of 4.8% through 2036, which raises concern that emissions production will outpace related technological advancement. A...

  12. Present scenario of air quality in Delhi: a case study of CNG implementation

    International Nuclear Information System (INIS)

    The present study discusses the ambient air quality of Delhi from the point of view of change from diesel to Compressed Natural Gas (CNG) in transportation in Delhi. Several initiatives were taken to reduce extremely high levels of pollutants present in the ambient air of urban city. One of the initiatives was to move public transport to CNG, which has been implemented in Delhi since April 2001. Delhi boasted CNG in nearly 2200 buses, 25,000 three wheelers, 6000 taxis and 10,000 cars. However, more than half of the vehicles are yet to be changed to CNG. A relative comparison of ambient air concentration of pollutants, e.g. carbon monoxide (CO), sulphur dioxide (SO2), suspended particulate matter (SPM) and oxides of nitrogen (NOx), emitted from transport sector, during the years 1995-2000 (without CNG) and the year 2001 (with CNG) has been made in order to assess the impact of CNG vehicles on ambient air quality in Delhi. It has been found that concentration contribution of above pollutants has been reduced considerably. The annual average concentration of SPM came down to 347 from 405μg m-3, which is still beyond the permissible limits. The concentration of annual averages of CO, SO2 and NOx decreased to 4197 from 4681μg m-3, 14 from 18μg m-3 and 34 from 36μg m-3, respectively, and are well within the permissible limits. An analysis of SO2/NOx and CO/NOx concentrations, whose correlation coefficient r2 has the values 0.7613 and 0.7903, respectively, indicates that point sources are contributing to SO2 and mobile sources are contributing to NOx concentrations. (Author)

  13. Indoor air quality scenario in India-An outline of household fuel combustion

    Science.gov (United States)

    Rohra, Himanshi; Taneja, Ajay

    2016-03-01

    Most of the research around the world has been on outdoor air pollution, but in India we have a more severe problem of Indoor Air Pollution (IAP). The foremost factor cited for is burning of fossil fuels for cooking. Among the 70% of the country's rural population, about 80% households rely on biomass fuel making India to top the list of countries with largest population lacking access to cleaner fuel for cooking. 4 million deaths and 5% disability-adjusted life-years is an upshot of exposure to IAP from unhealthy cooking making it globally the most critical environmental risk factor. India alone bears the highest burden (28% needless deaths) among developing countries. Moreover, about ¼ of ambient PM2.5 in the country comes from household cookfuels. These considerations have prompted the discussion of the present knowledge on the disastrous health effects of pollutants emitted by biomass combustion in India. Additionally, Particulate Matter as an indoor air pollutant is highlighted with main focus on its spatial temporal variation and some recent Indian studies are further explored. As there are no specific norms for IAP in India, urgent need has arisen for implementing the strategies to create public awareness. Moreover improvement in ventilation and modification in the pattern of fuel will also contribute to eradicate this national health issue.

  14. A simplified physically-based model to calculate surface water temperature of lakes from air temperature in climate change scenarios

    Science.gov (United States)

    Piccolroaz, S.; Toffolon, M.

    2012-12-01

    conditions. As a general result, the model allows one to obtain long-term series of estimated water temperatures, which can be valuably considered in climate change studies. The model has been applied to different lakes (Lake Baikal, Siberia; Lake Garda, Italy; Great Lakes, Canada and USA; Lake Mara, Canada) showing a noticeable agreement with the validation datasets and allowing for predictions of future trends of lake surface water temperature. Finally, it is worth noting that if the model is calibrated using air temperature series from climate models (global scale) and measured records of water temperature (lake scale), air temperatures are contemporaneously converted and downscaled. In conclusion, the model can be used as a downscaling tool, both for historical conditions and projected scenarios.

  15. Trends in aircraft emissions. Simulation of two air traffic scenarios in Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Larson, L.G.; Palsson, A. [The Aeronautical Research Inst. of Sweden, Bromma (Sweden). The Swedish Civil Aviation Administration

    1997-12-31

    The developing trends of emissions from aviation in Sweden have been studied by means of flight and emissions simulation. The objective was to investigate whether technical improvements will allow Swedish air traffic to increase, without exceeding national regulations for pollution in the future. It was found that, due to development of aircraft engines and, to some extent, improvement of aerodynamic designs, the fuel consumption and thus the emissions of carbon dioxide will decrease in the future. The decrease of nitrous oxides is predicted to be significant due to advances in engine technology. (author) 4 refs.

  16. Constitutive kinematic modes and shapes during vehicle ingress/egress.

    Science.gov (United States)

    Shippen, James; May, Barbara

    2016-09-01

    A study was undertaken to investigate the kinematics of older users of passenger vehicles during ingress/egress and to seek correlations between their movement and comfort rating assigned by the subjects to the ease of vehicle ingress and egress. A principal component analysis was performed on the subjects' kinematics to identify the underlying modes of movement employed by the subjects. It was found that a small number of modes could describe the movements of all the subjects across all of the vehicles. Within the subspace defined by the modal vectors, shapes were found which correlated to the comfort rating for ease of ingress and egress which the subjects had assigned to each of the cars. Knowledge of these shapes which correspond to good and poor ingress and egress will be useful to the designers of interiors and exteriors of passenger vehicles for the older person. It is recommended that vehicle designs for the older person should attempt to avoid body positions which require excessive ankle articulation and lumbar flexion/extension during ingress and egress. PMID:27184320

  17. Chemical Transport and Reduced-Form Models for Assessing Air Quality Impacts of Current and Future Energy Scenarios

    Science.gov (United States)

    Adams, P. J.

    2015-12-01

    Though essential for informed decision-making, it is challenging to estimate the air quality and public health impacts associated with current and future energy generation scenarios because the analysis must address the complicated atmospheric processes that air pollutants undergo: emissions, dispersion, chemistry, and removal. Employing a chemical transport model (CTM) is the most rigorous way to address these atmospheric processes. However, CTMs are expensive from a computational standpoint and, therefore, beyond the reach of policy analysis for many types of problems. On the other hand, previously available reduced-form models used for policy analysis fall short of the rigor of CTMs and may lead to biased results. To address this gap, we developed the Estimating Air pollution Social Impacts Using Regression (EASIUR) method, which builds parameterizations that predict per-tonne social costs and intake fractions for pollutants emitted from any location in the United States. Derived from a large database of tagged CTM simulations, the EASIUR method predicts social costs almost indistinguishable from a full CTM but with negligible computational requirements. We found that the average mortality-related social costs from inorganic PM2.5 and its precursors in the United States are 150,000-180,000/t EC, 21,000-34,000/t SO2, 4,200-15,000/t NOx, and 29,000-85,000/t NH3. This talk will demonstrate examples of using both CTMs and reduced-form models for assessing air quality impacts associated with current energy production activities as well as a future deployment of carbon capture and sequestration.

  18. The importance of meteorological scales to forecast air pollution scenarios on coastal complex terrain

    Directory of Open Access Journals (Sweden)

    J. L. Palau

    2005-01-01

    Full Text Available Some of the meteorological approaches commonly considered in urban air pollution models do not take into account the importance of the smaller scales in the meteorology of complex-terrain coastal sites. The aim of this work is to estimate the impact of using the proper meteorological scales when simulating the behaviour of the pollutant concentrations emitted in the lower layers over coastal complex terrain areas. The availability of experimental measurements of a power plant plume near the Castellón conurbation (on the Spanish Mediterranean coast has allowed us to use this plume as a tracer of opportunity of the lower atmosphere to check the results of a simulation exercise using the RAMS mesoscale model coupled to the HYPACT particle model. The results obtained show that in a complex-terrain coastal site, because of the strong effect of the meteorological interactions between the different scales on the integral advection and the turbulent dispersion of pollutants, using an inadequate scale to solve the meteorology can result in a very big gap in the simulation of lower-layer pollutant behaviour at urban scales.

  19. Sustainable passenger road transport scenarios to reduce fuel consumption, air pollutants and GHG (greenhouse gas) emissions in the Mexico City Metropolitan Area

    International Nuclear Information System (INIS)

    This paper presents passenger road transport scenarios that may assist the MCMA (Mexico City Metropolitan Area) in achieving lower emissions in both criteria air pollutants (CO, NOx, NMVOC (non-methane volatile organic compounds), and PM10) and GHG (greenhouse gas) (CH4, N2O and CO2), while also promoting better mobility and quality of life in this region. We developed a bottom-up model to estimate the historical trends of energy demand, criteria air pollutants and GHG emissions caused by passenger vehicles circulating in the Mexico City Metropolitan Area (MCMA) in order to construct a baseline scenario and two mitigation scenarios that project their impact to 2028. Mitigation scenario “eff” considers increasing fuel efficiencies and introducing new technologies for vehicle emission controls. Mitigation scenario “BRT” considers a modal shift from private car trips to a Bus Rapid Transport system. Our results show significant reductions in air pollutants and GHG emissions. Incentives and environmental regulations are needed to enable these scenarios. - Highlights: • More than 4.2 million passenger vehicles in the MCMA (Mexico City Metropolitan Area) that represent 61% of criteria pollutants and 44% of GHG (greenhouse gas) emissions. • Emissions of CO, NOx and NMVOC (non-methane volatile organic compounds) in baseline scenario decrease with respect to its 2008 value because emission standards. • Emissions of PM10 and GHG increase in baseline scenario. • Emissions of PM10 and GHG decrease in eff + BRT scenario from year 2020. • Additional reductions are possible with better standards for diesel vehicles and other technologies

  20. Characteristics of Water Ingress in Norwegian Subsea Tunnels

    Science.gov (United States)

    Nilsen, Bjørn

    2014-05-01

    Water ingress represents one of the main challenges in subsea tunnelling, particularly when this occurs in sections with poor rock mass quality. This paper is discussing the main characteristics of water ingress in subsea hard rock tunnels based on the experience from almost 50 such tunnels that have been built in Norway. Following a brief description of the geological conditions and the basic design of the subsea tunnels, pre-construction investigations and investigations during excavation are discussed with particular emphasis on prediction of water ingress. Two cases with particularly difficult conditions; the Bjorøy tunnel and the Atlantic Ocean tunnel, are discussed in detail. In these cases, large water inflow with pressure of up to 2.4 MPa was encountered at major faults/weakness zones during excavation, and special procedures were required to cope with the problems. Based on the experience from the Norwegian projects, it is concluded that continuous follow-up by experienced engineering geologists, probe drilling with the drilling jumbo and pre-grouting where required are the most important factors for coping with water ingress and ensuring stability.

  1. Probabilistic Models and Computational Methods for Chloride Ingress in Concrete

    DEFF Research Database (Denmark)

    Engelund, S.

    Within the last decades it has been recognized that reinforced concrete structures are subject to a number of destructive mechanisms which might affect the structure in such a way that it is not able to fulfil its purpose efficiently. The present report focuses on chloride ingress and chloride-in...

  2. Vapor extraction, air sparging, and bioventing in combination form a technically and cost effective scenario to remediate petroleum hydrocarbons

    International Nuclear Information System (INIS)

    When the appropriate site conditions exist, air sparging, vapor extraction and bioventing can be combined to form a technically and cost effective scenario to remediate petroleum hydrocarbon contaminated soils. A former Gulf Terminal in Upstate New York meets these conditions. The site geology consists of highly permeable sands and gravels with only trace amounts of silt. The groundwater table is approximately 15 feet below the ground surface which provides an ideal vadose zone. The site contaminants are petroleum fuel residuals primarily from the former storage and transfer of gasoline distillates. A series of pilot studies were conducted at the site in July, August, and September of 1994 to determine the validity of the proposed technologies. Based on the pilot study results, it was determined that the combined technologies of soil vapor extraction, air sparging, and bioventing could be used to effectively remediate the site. Using the pilot study data as the design basis, Parsons ES designed and installed a full-scale remediation system to address both the vadose and phreatic zone contaminants. The SVE portion of the system was placed into operation in April of 1995, and to date has removed over 12,000 pounds of petroleum hydrocarbons, including over 30 pounds of benzene. The overall costs for remediating the site including pilot studies, detailed design, system installation, and one year of operation are estimated at $5.60 per cubic yard for the estimated 35,000 cubic yards of contaminated soil at the site. The pilot study, full-scale operational results, and projected remediation costs are the focus of this paper

  3. A role of texture in controlling oxidation and hydrogen ingress in ZR-NB pressure tubes

    International Nuclear Information System (INIS)

    A nano -scale microstructural computer model for predicting ZrO2 structure and texture development during oxidation of Zr-Nb alloy has been proposed. The model assumes that the main driving force for texture formation in oxide and growth of the oxide grains is the compression stress parallel to the oxide surface. The orientation of substrate grains also plays an important role. The oxide texture, microstructure, grain boundary character distribution and the stress development can be simulated. The substrate texture, microstructure, phase composition are the major factors determining the oxide structure. This structure controls the oxygen and hydrogen transport through oxide layer; therefore the model that predicts the oxide structure allows the simulation of the corrosion behaviour and hydrogen ingress through the oxide. The proposed model has been used to predict the Zr oxidation kinetics in air for different textures of the substrate. The result of simulation agrees with character of changes observed in oxidation experiments. Eventually, this model will be able to simulate the hydrogen ingress process and to predict hydride formation and cracking of the pressure tube. The comparison between the simulation and experimental results will he presented. (author)

  4. Dirt Ingress Behavior of Wipers for Hydraulic Cylinders

    OpenAIRE

    Barillas, Gonzalo A.; Richter, Sören; Weber, Jürgen

    2016-01-01

    Dirt ingress in hydraulic cylinders is one of the sources that leads to pollution of hydraulic systems. There are already several test rigs to investigate external contamination mechanisms. However, until now only the behavior of the whole sealing system was analyzed. A new testing method to understand the dirt particle transport between a reciprocating motioned rod and a wiper is presented. The new approach aims to avoid known issues such as limited reproducibility and long duration. The pap...

  5. Deuterium ingress at rolled joints in Embalse nuclear power plant

    International Nuclear Information System (INIS)

    Deuterium ingress model at the Rolled Joint has been extensively used for CANDU Nuclear Power Plants Operators in the Life Management of the Pressure Tubes. The importance of understanding the model is vital to avoid delayed hydride cracking at the Rolled Joint. This work reports the first step on develop the model presented on literature to be used in Argentinean CANDU 6, Embalse Nuclear Power Plant. (author)

  6. Emission scenarios for air quality management and applications at local and regional scales including the effects of the future European emission regulation (2015 for the upper Rhine valley

    Directory of Open Access Journals (Sweden)

    J.-L. Ponche

    2004-12-01

    Full Text Available Air quality modeling associated with emission scenarios has become an important tool for air quality management. The set-up of realistic emission scenarios requires accurate emission inventories including the whole methodology used to calculate the emissions. This means a good description of the source characteristics including a detailed composition of the emitted fluxes. Two main approaches are used. The so-called bottom-up approach that relies on the modification of the characteristics of the sources and the top-down approach whose goal is generally to reach standard pollutant concentration levels. This paper is aimed at providing a general methodology for the elaboration of such emission scenarios and giving examples of applications at local and regional scales for air quality management. The first example concerns the impact of the installation of the urban tramway in place of the road traffic in the old centre of Strasbourg. The second example deals with the use of oxygenated and reformulated car fuels on local (Strasbourg urban area and regional (upper Rhine valley scales. Finally, we analyze in detail the impacts of the incoming European emission regulation for 2015 on the air quality of the upper Rhine valley.

  7. Emission scenarios for air quality management and applications at local and regional scales including the effects of the future European emission regulation (2015 for the upper Rhine valley

    Directory of Open Access Journals (Sweden)

    J.-L. Ponche

    2005-01-01

    Full Text Available Air quality modeling associated with emission scenarios has become an important tool for air quality management. The set-up of realistic emission scenarios requires accurate emission inventories including the whole methodology used to calculate the emissions. This means a good description of the source characteristics including a detailed composition of the emitted fluxes. Two main approaches are used. The so-called bottom-up approach that relies on the modification of the characteristics of the sources and the top-down approach whose goal is generally to reach standard pollutant concentration levels. This paper is aimed at providing a general methodology for the elaboration of such emission scenarios and giving examples of applications at local and regional scales for air quality management. The first example concerns the impact of the installation of the urban tramway in place of the road traffic in the old centre of Strasbourg. The second example deals with the use of oxygenated and reformulated car fuels on local (Strasbourg urban area and regional (upper Rhine valley scales. Finally, we analyze in detail the impacts of the incoming European emission regulation for 2015 on the air quality of the upper Rhine valley.

  8. Analysis on blow-down transient in water ingress accident of high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    Water ingress into the primary circuit is generally recognized as one of the severe accidents with potential hazard to the modular high temperature gas-cooled reactor, which will cause a positive reactivity introduction with the increase of steam density in reactor core to enhance neutron slowing-down, also the chemical corrosion of graphite fuel elements and the damage of reflector structure material. The increase of the primary pressure may result in the opening of the safety valves, consequently leading the release of radioactive isotopes and flammable water gas. The research on water ingress transient is significant for the verification of inherent safety characteristics of high temperature gas-cooled reactor. The 200 MWe high temperature gas-cooled reactor (HTR-PM), designed by the Institute of Nuclear and New Energy Technology of Tsinghua University, is exampled to be analyzed in this paper. The design basis accident (DBA) scenarios of double-ended guillotine break of single heat-exchange tube (steam generator heat-exchange tube rupture) are simulated by the thermal-hydraulic analysis code, and some key concerns which are relative to the amount of water into the reactor core during the blow-down transient are analyzed in detail. The results show that both of water mass and steam ratio of the fluid spouting from the broken heat-exchange tube are affected by break location, which will increase obviously with the broken location closing to the outlet of the heat-exchange tube. The double-ended guillotine rupture at the outlet of the heat-exchange will result more steam penetrates into the reactor core in the design basis accident of water ingress. The mass of water ingress will also be affected by the draining system. It is concluded that, with reasonable optimization on design to balance safety and economy, the total mass of water ingress into the primary circuit of reactor could be limited effectively to meet the safety requirements, and the pollution of

  9. Air-quality in the mid-21st century for the city of Paris under two climate scenarios; from regional to local scale

    OpenAIRE

    K. Markakis; Valari, M.; Colette, A.; Sanchez, O.; O. Perrussel; C. Honore; Vautard, R.; Z. Klimont; Rao, S.

    2014-01-01

    Ozone and PM2.5 concentrations over the city of Paris are modeled with the CHIMERE air-quality model at 4 km × 4 km horizontal resolution for two future emission scenarios. High-resolution (1 km × 1 km) emission projection until 2020 for the greater Paris region is developed by local experts (AIRPARIF) and is further extended to year 2050 based on regional scale emission projections developed by the Global Energy Assessment. Model evaluation is performed bas...

  10. Clustering of airport cities and cluster dynamic for the air passenger demand forecasting model based on a socio-economic scenario

    OpenAIRE

    Terekhov, Ivan; Gollnick, Volker

    2015-01-01

    This study presents methods of grouping cities into clusters by their socio-economic indicators and tracing changes in the content of cluster within a socio-economic scenario. For cities’ grouping, three main clustering approaches have been analyzed: hierarchical, exclusive and probabilistic clustering. Analyzing advantages and disadvantages of these approaches, probabilistic clustering of normal mixture has been chosen to separate cities from the air passenger demand (APD) forecasting model....

  11. CODEX and RUSET air oxidation experiments

    International Nuclear Information System (INIS)

    In the late phase of a severe accident after the failure of the lower head, or in shut-down state with open reactor vessel the interaction of air with high temperature core materials can be expected. The intense oxidation of zirconium components can strongly affect the evolution of the severe accident scenario and chemical interaction of air with fission products can influence the radiological source term due to the volatilization of ruthenium oxide. The KFKI Atomic Energy Institute initiated an experimental program in order to extend our knowledge in this field and to provide data for model development and better estimation of the consequences of air ingress type accidents. Two integral tests were performed in 1998-1999 with electrically heated nine-rod pressurized water reactor type bundles in the CODEX (Core Degradation Experiment) facility. The CODEX-AIT-1 (Air Ingress Test) and AIT-2 experiments indicated the acceleration of oxidation phenomena and core degradation process in air atmosphere under severe accident conditions. The degradation process was accompanied with zirconium-nitride formation and release of large number of aerosol particles, some of which contained uranium. The enhanced fission product release was not addressed in these tests. The oxidation behavior and release of fission products in high temperature air is investigated in the current RUSET program (Ruthenium Separate Effect Tests) 2002-2004. The first series of experiments was performed with fission product simulants mixed into ZrO2 or UC2 powder. Fast oxidation and release of Ru and other fission products was observed. The formed oxides deposited in the cold part of the facility and only few percent of the inventory reached the room temperature samplers. In 2003-2004 the RUSET experiments will be continued with short fuel rod segments, containing inactive fission product simulant materials. (author)

  12. Air quality in the mid-21st century for the city of Paris under two climate scenarios; from the regional to local scale

    OpenAIRE

    K. Markakis; Valari, M.; Colette, A.; Sanchez, O.; O. Perrussel; C. Honore; Vautard, R.; Z. Klimont; Rao, S.

    2014-01-01

    Ozone and PM2.5 concentrations over the city of Paris are modeled with the CHIMERE air-quality model at 4 km × 4 km horizontal resolution for two future emission scenarios. A high-resolution (1 km × 1 km) emission projection until 2020 for the greater Paris region is developed by local experts (AIRPARIF) and is further extended to year 2050 based on regional-scale emission projections developed by the Global Energy Assessment. Model evaluation is performed based on a 10-year...

  13. Prediction of chloride ingress and binding in cement paste

    DEFF Research Database (Denmark)

    Geiker, Mette Rica; Nielsen, Erik Pram; Herforth, Duncan

    2007-01-01

    Portland cement pastes at any content of chloride, alkalis, sulfates and carbonate was verified experimentally and found to be equally valid when applied to other data in the literature. The thermodynamic model for predicting the phase equilibria in hydrated Portland cement was introduced into an existing...... Finite Difference Model for the ingress of chlorides into concrete which takes into account its multi-component nature. The “composite theory” was then used to predict the diffusivity of each ion based on the phase assemblage present in the hydrated Portland cement paste. Agreement was found between...... steady state diffusion however. It simply implies that incremental increases in the concentration of diffusing ions in the pore solution will rapidly re-equilibrate with the hydrates present locally, where, the greater the ratio of bound to free ions, the greater the buffering effect which slows down the...

  14. Ingress of water into solid nylon 6.6

    Science.gov (United States)

    Mansfield, P.; Bowtell, R.; Blackband, S.

    The ingress of water into Nylon 6.6 has been studied over a range of temperatures by nuclear magnetic resonance imaging techniques. The results have been used to extract the translational diffusion coefficient as a function of water concentration for various temperatures. These results in turn allow the activation energies to be evaluated. Other experiments have been made to measure the spin relaxation times T1 and T2. The results are interpreted using a two-phase exchange model from which good agreement for both the diffusion and relaxation-time data is obtained. High-pressure diffusion results also presented support the view that water is taken up preferentially at the amorphous amide sites in the Nylon and that pressure increases serve to force water onto sitccupied sites and/or onto occupied sites, giving up to three waters per amide site.

  15. Moisture ingress into electronics enclosures under isothermal conditions

    Science.gov (United States)

    Staliulionis, Ž.; Jabbari, M.; Hattel, J. H.

    2016-06-01

    The number of electronics used in outdoor environment is constantly growing. The humidity causes about 19 % of all electronics failures and, especially, moisture increases these problems due to the ongoing process of miniaturization and lower power consumption of electronic components. Moisture loads are still not understood well by design engineers, therefore this field has become one of the bottlenecks in the electronics system design. The objective of this paper is to model moisture ingress into an electronics enclosure under isothermal conditions. The moisture diffusion model is based on a 1D quasi-steady state (QSS) approximation for Fick's second law. This QSS approach is also described with an electrical analogy which gives a fast tool in modelling of the moisture response. The same QSS method is applied to ambient water vapour variations. The obtained results are compared to an analytical solution and very good agreement is found.

  16. The old problem of illiteracy remains: the educational scenario in the province of Buenos Aires during the 40s

    Directory of Open Access Journals (Sweden)

    Eva Mara Petitti

    2012-08-01

    Full Text Available In this study we will investigate the problem of illiteracy in the province of Buenos Aires during the decade of `40. We focus especially on the eve of the Domingo Mercante government (1946-1952 and in the early years of his administration. To accomplish this task, will we analyze two issues. First, the level of perceptions, namely, the diagnoses made ??by political officials before and after the promotion of Domingo Mercante as governor.  Second, the heterogeneity of the educational scene in the province of Buenos Aires during the decade. Anchored in existing studies analyzing Peronism from a regional perspective, we chose the case of the province of Buenos Aires, not only for their influence on political life in Argentina but also, because is the province has the highest school age population and internal migration.

  17. Air quality in the mid-21st century for the city of Paris under two climate scenarios; from the regional to local scale

    Science.gov (United States)

    Markakis, K.; Valari, M.; Colette, A.; Sanchez, O.; Perrussel, O.; Honore, C.; Vautard, R.; Klimont, Z.; Rao, S.

    2014-07-01

    Ozone and PM2.5 concentrations over the city of Paris are modeled with the CHIMERE air-quality model at 4 km × 4 km horizontal resolution for two future emission scenarios. A high-resolution (1 km × 1 km) emission projection until 2020 for the greater Paris region is developed by local experts (AIRPARIF) and is further extended to year 2050 based on regional-scale emission projections developed by the Global Energy Assessment. Model evaluation is performed based on a 10-year control simulation. Ozone is in very good agreement with measurements while PM2.5 is underestimated by 20% over the urban area mainly due to a large wet bias in wintertime precipitation. A significant increase of maximum ozone relative to present-day levels over Paris is modeled under the "business-as-usual" scenario (+7 ppb) while a more optimistic "mitigation" scenario leads to a moderate ozone decrease (-3.5 ppb) in year 2050. These results are substantially different to previous regional-scale projections where 2050 ozone is found to decrease under both future scenarios. A sensitivity analysis showed that this difference is due to the fact that ozone formation over Paris at the current urban-scale study is driven by volatile organic compound (VOC)-limited chemistry, whereas at the regional-scale ozone formation occurs under NOx-sensitive conditions. This explains why the sharp NOx reductions implemented in the future scenarios have a different effect on ozone projections at different scales. In rural areas, projections at both scales yield similar results showing that the longer timescale processes of emission transport and ozone formation are less sensitive to model resolution. PM2.5 concentrations decrease by 78% and 89% under business-as-usual and mitigation scenarios, respectively, compared to the present-day period. The reduction is much more prominent over the urban part of the domain due to the effective reductions of road transport and residential emissions resulting in the

  18. Air-quality in the mid-21st century for the city of Paris under two climate scenarios; from regional to local scale

    Science.gov (United States)

    Markakis, K.; Valari, M.; Colette, A.; Sanchez, O.; Perrussel, O.; Honore, C.; Vautard, R.; Klimont, Z.; Rao, S.

    2014-01-01

    Ozone and PM2.5 concentrations over the city of Paris are modeled with the CHIMERE air-quality model at 4 km × 4 km horizontal resolution for two future emission scenarios. High-resolution (1 km × 1 km) emission projection until 2020 for the greater Paris region is developed by local experts (AIRPARIF) and is further extended to year 2050 based on regional scale emission projections developed by the Global Energy Assessment. Model evaluation is performed based on a 10 yr control simulation. Ozone is in very good agreement with measurements while PM2.5 is underestimated by 20% over the urban area mainly due to a large wet bias in wintertime precipitation. A significant increase of maximum ozone relative to present time levels over Paris is modeled under the "business as usual" scenario (+7 ppb) while a more optimistic mitigation scenario leads to moderate ozone decrease (-3.5 ppb) in year 2050. These results are substantially different to previous regional scale projections where 2050 ozone is found to decrease under both future scenarios. A sensitivity analysis showed that this difference is due to the fact that ozone formation over Paris at the current, urban scale study, is driven by VOC-limited chemistry, whereas at the regional scale ozone formation occurs under NOx-sensitive conditions. This explains why the sharp NOx reductions implemented in the future scenarios have a different effect on ozone projections at different scales. In rural areas projections at both scales yield similar results showing that the longer time-scale processes of emission transport and ozone formation are less sensitive to model resolution. PM2.5 concentrations decrease by 78% and 89% under "business as usual" and "mitigation" scenarios respectively compared to present time period. The reduction is much more prominent over the urban part of the domain due to the effective reductions of road transport and residential emissions resulting in the smoothing of the large urban increment

  19. Air-quality in the mid-21st century for the city of Paris under two climate scenarios; from regional to local scale

    Directory of Open Access Journals (Sweden)

    K. Markakis

    2014-01-01

    Full Text Available Ozone and PM2.5 concentrations over the city of Paris are modeled with the CHIMERE air-quality model at 4 km × 4 km horizontal resolution for two future emission scenarios. High-resolution (1 km × 1 km emission projection until 2020 for the greater Paris region is developed by local experts (AIRPARIF and is further extended to year 2050 based on regional scale emission projections developed by the Global Energy Assessment. Model evaluation is performed based on a 10 yr control simulation. Ozone is in very good agreement with measurements while PM2.5 is underestimated by 20% over the urban area mainly due to a large wet bias in wintertime precipitation. A significant increase of maximum ozone relative to present time levels over Paris is modeled under the "business as usual" scenario (+7 ppb while a more optimistic mitigation scenario leads to moderate ozone decrease (−3.5 ppb in year 2050. These results are substantially different to previous regional scale projections where 2050 ozone is found to decrease under both future scenarios. A sensitivity analysis showed that this difference is due to the fact that ozone formation over Paris at the current, urban scale study, is driven by VOC-limited chemistry, whereas at the regional scale ozone formation occurs under NOx-sensitive conditions. This explains why the sharp NOx reductions implemented in the future scenarios have a different effect on ozone projections at different scales. In rural areas projections at both scales yield similar results showing that the longer time-scale processes of emission transport and ozone formation are less sensitive to model resolution. PM2.5 concentrations decrease by 78% and 89% under "business as usual" and "mitigation" scenarios respectively compared to present time period. The reduction is much more prominent over the urban part of the domain due to the effective reductions of road transport and residential emissions resulting in the smoothing of the large

  20. The impact of shipping emissions on air pollution in the greater North Sea region - Part 2: Scenarios for 2030

    Science.gov (United States)

    Matthias, V.; Aulinger, A.; Backes, A.; Bieser, J.; Geyer, B.; Quante, M.; Zeretzke, M.

    2016-01-01

    Scenarios for future shipping emissions in the North Sea have been developed in the framework of the Clean North Sea Shipping project. The effects of changing NOx and SO2 emissions were investigated with the CMAQ chemistry transport model for the year 2030 in the North Sea area. It has been found that, compared to today, the contribution of shipping to the NO2 and O3 concentrations will increase due to the expected enhanced traffic by more than 20 and 5 %, respectively, by 2030 if no regulation for further emission reductions is implemented in the North Sea area. PM2.5 will decrease slightly because the sulfur contents in ship fuels will be reduced as international regulations foresee. The effects differ largely between regions, seasons and date of the implementation of stricter regulations for NOx emissions from newly built ships.

  1. Analysis of Regional Climate Changes adjusted Future Urban Growth Scenarios and possibility of the future air quality prediction in Seoul Metropolitan Area (SMA), Korea

    Science.gov (United States)

    Kim, H.; Kim, Y.; Jeong, J.

    2012-12-01

    urbanized area. Additionally, we thought that the difference of variables like surface temperature and PBL height will surely create the variation of the future air quality in SMA. So, we examined the CMAQ (Community Modeling and Analysis System) model, which is usually to predict the timely variation and the spatial distribution of air pollutant like ozone, particular matter, to know the possibility of the prediction of the future air quality changes under the urban growth changes and ECHAM5/OM-1 A1B scenarios. To make the initial emission data for CMAQ modeling, we analyzed the National Air Pollutants emission data for past 12 years (1999~2010) generated by National institute of Environmental Research in Korea and assumed that future emission is increased linearly by 2050.

  2. Chloride ingress in cement paste and mortar measured by Electron Probe Micro Analysis

    DEFF Research Database (Denmark)

    Jensen, Ole Mejlhede

    1998-01-01

    Chloride ingress is a common cause of deterioration of reinforced concrete structures. Concrete may be exposed to chloride by sea water or deicing salts. The chloride initiates corrosion of the reinforcement which through expansion disrupts the concrete. Modelling the chloride ingress is an.......Chloride ingress in modern concretes cannot be followed with conventional measuring techniques. This makes it difficult to develop and test new models. However, prefatory experiments have shown that electron probe micro analysis, EPMA, is applicable for this purpose. The geometric resolution for the EPMA method is...

  3. Simulation of Water Vapor Ingress into PV-Modules under Different Climatic Conditions

    Directory of Open Access Journals (Sweden)

    Philip Hülsmann

    2013-01-01

    Full Text Available This work deals with the simulation of water vapor ingress into wafer-based PV-modules for long-term exposure under different climatic conditions. Measured material parameters together with climatic data sets from four test sites (tropic, moderate, alpine, and arid were used to calculate the water concentration inside of the encapsulant between solar cell and glass for a lifetime of 20 years. Two back-sheet materials (PET-based and PA-based combined with EVA as encapsulant were used in respect to their influence on water ingress. The results show faster water ingress for warmer regions, but the highest concentrations were found for the moderate test site. The water ingress was additionally influenced by the used encapsulant and back-sheet combination. In particular the temperature dependency of the mass transfer, which differs from material to material, was the focus of this investigation.

  4. TOPFLOW-PTS air-water experiments on the phase separation in the ECC nozzle and the ECC water mixing during PTS scenarios

    International Nuclear Information System (INIS)

    In two-phase Pressurized Thermal Shock scenarios several thermal hydraulic phenomena, such as direct contact condensation, entrainment of steam bubbles and multi-scale momentum transfer are involved. The TOPFLOW-PTS experimental assembly represents a 1:2.5 scaled model of a PWR downcomer, cold leg with emergency core cooling injection and a pump simulator. It is build up for the development and validation of CFD models. The setup is highly instrumented - a large number of thermocouples, an infrared and a high-speed camera as well as wire mesh sensors are used to obtain CFD-grade data. As a first step air-water experiments were done with the special aim to investigate the behaviour of the liquid jet from the ECC injection into the cold leg. They indicated that the jet momentum at the impact position is very important for the mixing process and stratification inside the ECC nozzle needs to be considered in CFD calculations. (author)

  5. Nde for Water Ingression in Composite Radomes on Aircraft

    Science.gov (United States)

    Hsu, David K.; Barnard, Daniel J.; Kite, Adam H.; Kim, Ki-Bok

    2008-02-01

    Aircraft radomes, being an electronic window for the radar, are made of nonconducting composite sandwiches with glass or silica fiber-reinforced facesheet and Nomex honeycomb or foam core. Trapped water or moisture can produce shadow on the image and severely degrade the performance of the radar. To detect water ingression in radomes, the available NDE techniques include x-ray radiography, infrared thermography, and a radome moisture meter that measures the RF power loss caused by the presence of water. In this work we explore the utility of commercially available capacitive sensors with co-planar electrodes that measure the change of the dielectric constant in the fringing field. These capacitive sensors, such as the electronic stud finder and moisture meters for wood, can exploit the large dielectric constant of water and serve as one-sided detectors for water and moisture in radomes. The sensitivities of the various moisture meters were compared in the experimental detection of water introduced into radome panels and water and moisture trapped in retired radomes.

  6. Durable concrete for a waste repository - Measurement of ionic ingress

    International Nuclear Information System (INIS)

    A waste repository for the below ground disposal of low level radioactive waste is planned at Chalk River Nuclear Laboratories. It relies greatly on the durability of concrete for the required 500 year service life. A research program to design durable concrete and predict its service life is in progress. The degradation of the concrete depends to a large extent on the rate of ingress of corrosive agents. Penetration of chloride and sulfate ions are particularly relevant. Twenty mix formulations were developed to create various types and qualities of concrete, and to study their behavior in different site environmental conditions. A total of 1,000 concrete specimens are being exposed at 20C and 45C to 25 different combinations of the corrosive agents including CO2. Procedures to measure the ionic profiles and to determine the factors controlling diffusion of the ions in the various concretes have been developed. Results of selected concrete systems exposed to chloride and sulfate solutions for 1 year are presented and discussed in terms of pore structure and permeability parameters of the concrete

  7. Investigation of tritium activity ingress to pressure suppression pool

    International Nuclear Information System (INIS)

    Kakrapar Atomic Power Station is a standardised design Indian PHWR consisting of twin units of 220 MWe each. Pressure suppression pool situated at the basement of reactor building holds about 2200 m3 of DM water. It acts as a media separating the high enthalpy areas from low enthalpy areas and remain passive during normal operation. During LOCA it reduces the pressure in RB atmosphere by condensing the steam passing through it. In both units of KAPS tritium activity is observed in suppression pool, most predominantly in KAPS-1. Activity build up in suppression pool can act as potential source of tritium activity in RB atmosphere leading to increased internal exposure of occupational workers. Also during de-watering of suppression pool, this water adds to the amount of liquid waste generated from the station which eventually results in exposure of the public to tritium. This paper discusses the activity build up trend in KAPS-1 suppression pool, its sources, works done to prevent the activity ingress and suggestions for design improvement. (author)

  8. Projections of high resolution climate changes for South Korea using multiple-regional climate models based on four RCP scenarios. Part 1: Surface air temperature

    Science.gov (United States)

    Suh, Myoung-Seok; Oh, Seok-Geun; Lee, Young-Suk; Ahn, Joong-Bae; Cha, Dong-Hyun; Lee, Dong-Kyou; Hong, Song-You; Min, Seung-Ki; Park, Seong-Chan; Kang, Hyun-Suk

    2016-05-01

    We projected surface air temperature changes over South Korea during the mid (2026-2050) and late (2076-2100) 21st century against the current climate (1981-2005) using the simulation results from five regional climate models (RCMs) driven by Hadley Centre Global Environmental Model, version 2, coupled with the Atmosphere- Ocean (HadGEM2-AO), and two ensemble methods (equal weighted averaging, weighted averaging based on Taylor's skill score) under four Representative Concentration Pathways (RCP) scenarios. In general, the five RCM ensembles captured the spatial and seasonal variations, and probability distribution of temperature over South Korea reasonably compared to observation. They particularly showed a good performance in simulating annual temperature range compared to HadGEM2-AO. In future simulation, the temperature over South Korea will increase significantly for all scenarios and seasons. Stronger warming trends are projected in the late 21st century than in the mid-21st century, in particular under RCP8.5. The five RCM ensembles projected that temperature changes for the mid/late 21st century relative to the current climate are +1.54oC/+1.92oC for RCP2.6, +1.68oC/+2.91oC for RCP4.5, +1.17oC/+3.11oC for RCP6.0, and +1.75oC/+4.73oC for RCP8.5. Compared to the temperature projection of HadGEM2-AO, the five RCM ensembles projected smaller increases in temperature for all RCP scenarios and seasons. The inter-RCM spread is proportional to the simulation period (i.e., larger in the late-21st than mid-21st century) and significantly greater (about four times) in winter than summer for all RCP scenarios. Therefore, the modeled predictions of temperature increases during the late 21st century, particularly for winter temperatures, should be used with caution.

  9. Projections of high resolution climate changes for South Korea using multiple-regional climate models based on four RCP scenarios. Part 1: surface air temperature

    Science.gov (United States)

    Suh, Myoung-Seok; Oh, Seok-Geun; Lee, Young-Suk; Ahn, Joong-Bae; Cha, Dong-Hyun; Lee, Dong-Kyou; Hong, Song-You; Min, Seung-Ki; Park, Seong-Chan; Kang, Hyun-Suk

    2016-05-01

    We projected surface air temperature changes over South Korea during the mid (2026-2050) and late (2076-2100) 21st century against the current climate (1981-2005) using the simulation results from five regional climate models (RCMs) driven by Hadley Centre Global Environmental Model, version 2, coupled with the Atmosphere- Ocean (HadGEM2-AO), and two ensemble methods (equal weighted averaging, weighted averaging based on Taylor's skill score) under four Representative Concentration Pathways (RCP) scenarios. In general, the five RCM ensembles captured the spatial and seasonal variations, and probability distribution of temperature over South Korea reasonably compared to observation. They particularly showed a good performance in simulating annual temperature range compared to HadGEM2-AO. In future simulation, the temperature over South Korea will increase significantly for all scenarios and seasons. Stronger warming trends are projected in the late 21st century than in the mid-21st century, in particular under RCP8.5. The five RCM ensembles projected that temperature changes for the mid/late 21st century relative to the current climate are +1.54°C/+1.92°C for RCP2.6, +1.68°C/+2.91°C for RCP4.5, +1.17°C/+3.11°C for RCP6.0, and +1.75°C/+4.73°C for RCP8.5. Compared to the temperature projection of HadGEM2-AO, the five RCM ensembles projected smaller increases in temperature for all RCP scenarios and seasons. The inter-RCM spread is proportional to the simulation period (i.e., larger in the late-21st than mid-21st century) and significantly greater (about four times) in winter than summer for all RCP scenarios. Therefore, the modeled predictions of temperature increases during the late 21st century, particularly for winter temperatures, should be used with caution.

  10. Impact of storage position on oxygen ingress through different closures into wine bottles.

    Science.gov (United States)

    Lopes, Paulo; Saucier, Cédric; Teissedre, Pierre-Louis; Glories, Yves

    2006-09-01

    Wine bottle aging is extremely dependent on the oxygen barrier properties of closures. Kinetics of oxygen ingress through different closures into bottles was measured by a nondestructive colorimetric method from 0.25 to 2.5 mL of oxygen. After 12, 24, and 36 months of storage, only the control (glass bottle ampule) was airtight. Other closures displayed different oxygen ingress rates, which were clearly influenced by the closure type and were independent of bottle storage position (upright, laid down) for most of the closures tested, at least during the first 24 months of the experiment under controlled conditions. The oxygen ingress rates into bottles were lowest in screw caps and "technical" corks, intermediate in conventional natural cork stoppers, and highest in the synthetic closures. PMID:16939334

  11. Air oxidation behavior of fuel for the high temperature engineering test reactor (HTTR)

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Hironobu; Hayashi, Kimio; Fukuda, Kousaku (Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment)

    1992-08-01

    The oxidation behavior of the HTTR fuel was studied with respect to the scenario of an air ingress accident which had been assessed in the HTTR safety analysis. The coated fuel particles were heated under a sufficient air flow in the temperature range of 900-1400degC for maximum duration of 600 h (at 1300degC). Failure fractions of the SiC coating layer after the heat treatments remained within the fraction at the fuel production. And the failure behavior of the SiC layer did not depend on such heating conditions as the temperature and the duration in the present experiment. It was confirmed by scanning electron microscopy (SEM), X-ray diffraction and laser Raman spectroscopy that a thin oxide film was formed on the SiC layer by the heat treatments. (author).

  12. Air oxidation behavior of fuel for the high temperature engineering test reactor (HTTR)

    International Nuclear Information System (INIS)

    The oxidation behavior of the HTTR fuel was studied with respect to the scenario of an air ingress accident which had been assessed in the HTTR safety analysis. The coated fuel particles were heated under a sufficient air flow in the temperature range of 900-1400degC for maximum duration of 600 h (at 1300degC). Failure fractions of the SiC coating layer after the heat treatments remained within the fraction at the fuel production. And the failure behavior of the SiC layer did not depend on such heating conditions as the temperature and the duration in the present experiment. It was confirmed by scanning electron microscopy (SEM), X-ray diffraction and laser Raman spectroscopy that a thin oxide film was formed on the SiC layer by the heat treatments. (author)

  13. Assessment of Water Ingress Accidents in a Modular High-Temperature Gas-Cooled Reactor

    OpenAIRE

    Zhang, Z.; Dong, Y.; Scherer, W.

    2005-01-01

    Severe water ingress accidents in the 200-MW HTR-module were assessed to determine the safety margins of modular pebble-bed high-temperature gas-cooled reactors (HTR-module). The 200-MW HTR-module was designed by Siemens under the criteria that no active safety protection systems were necessary because of its inherent safe nature. For simulating the behavior of the HTR-module during severe water ingress accidents, a water, steam, and helium multiphase cavity model was developed and implemente...

  14. Scenario analysis

    NARCIS (Netherlands)

    Li, L.; Braat, L.C.; Lei, G.; Arets, E.J.M.M.; Liu, J.; Jiang, L.; Fan, Z.; Liu, W.; He, H.; Sun, X.

    2014-01-01

    This chapter presents the results of the scenario analysis of China’s ecosystems focusing on forest, grassland, and wetland ecosystems. The analysis was undertaken using Conversion of Land Use Change and its Effects (CLUE) modeling and an ecosystem service matrix (as explained below) complemented by

  15. Scenario? Guilty!

    DEFF Research Database (Denmark)

    Kyng, Morten

    1992-01-01

    Robert Campbell categorizes the word "scenario" as a buzzword, identifies four major uses within HCI and suggests that we adopt new terms differentiating these four uses of the word. My first reaction to reading the article was definitely positive, but rereading it gave me enough second thoughts to...

  16. Evaluation of ATP measurements to detect microbial ingress by wastewater and surface water in drinking water

    DEFF Research Database (Denmark)

    Vang, Óluva Karin; Corfitzen, Charlotte B.; Smith, Christian;

    2014-01-01

    Fast and reliable methods are required for monitoring of microbial drinking water quality in order to protect public health. Adenosine triphosphate (ATP) was investigated as a potential real-time parameter for detecting microbial ingress in drinking water contaminated with wastewater or surface...... water. To investigate the ability of the ATP assay in detecting different contamination types, the contaminant was diluted with non-chlorinated drinking water. Wastewater, diluted at 10(4) in drinking water, was detected with the ATP assay, as well as 10(2) to 10(3) times diluted surface water....... To improve the performance of the ATP assay in detecting microbial ingress in drinking water, different approaches were investigated, i.e. quantifying microbial ATP or applying reagents of different sensitivities to reduce measurement variations; however, none of these approaches contributed significantly...

  17. Final Report Balancing energy conservation and occupant needs in ventilation rate standards for Big Box stores in California. Predicted indoor air quality and energy consumption using a matrix of ventilation scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Apte, Michael G. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mendell, Mark J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sohn, Michael D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Dutton, Spencer M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Berkeley, Pam M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Spears, Michael [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2011-02-01

    Through mass-balance modeling of various ventilation scenarios that might satisfy the ASHRAE 62.1 Indoor Air Quality (IAQ) Procedure, we estimate indoor concentrations of contaminants of concern (COCs) in California “big box” stores, compare estimates to available thresholds, and for selected scenarios estimate differences in energy consumption. Findings are intended to inform decisions on adding performance-based approaches to ventilation rate (VR) standards for commercial buildings. Using multi-zone mass-balance models and available contaminant source rates, we estimated concentrations of 34 COCs for multiple ventilation scenarios: VRmin (0.04 cfm/ft2 ), VRmax (0.24 cfm/ft2 ), and VRmid (0.14 cfm/ft2 ). We compared COC concentrations with available health, olfactory, and irritant thresholds. We estimated building energy consumption at different VRs using a previously developed EnergyPlus model. VRmax did control all contaminants adequately, but VRmin did not, and VRmid did so only marginally. Air cleaning and local ventilation near strong sources both showed promise. Higher VRs increased indoor concentrations of outdoor air pollutants. Lowering VRs in big box stores in California from VRmax to VRmid would reduce total energy use by an estimated 6.6% and energy costs by 2.5%. Reducing the required VRs in California’s big box stores could reduce energy use and costs, but poses challenges for health and comfort of occupants. Source removal, air cleaning, and local ventilation may be needed at reduced VRs, and even at current recommended VRs. Also, alternative ventilation strategies taking climate and season into account in ventilation schedules may provide greater energy cost savings than constant ventilation rates, while improving IAQ.

  18. Operating experience of a sodium rig following the ingress of oil

    International Nuclear Information System (INIS)

    The experience of operating the Small Water Leak Rig at Dounreay in the two years following the ingress into the sodium of silicone oil from the pump is reported. The carbon penetration into the rig pipework has been monitored and has been found to agree with a diffusion model. The predictions based on this model have enabled an operating strategy to be determined to allow continued operation of the rig. (author)

  19. The reactivity effects of steam ingress into the core of gas-cooled fast reactors

    International Nuclear Information System (INIS)

    Steam ingress reactivity effect is caused by steam ingress into the core of GCFRs through coolant channels from the secondary coolant system during a hypothetical accident. This reactivity effect in GCFR can be considered one of the most important safety-related physics parameters as is the sodium void reactivity effect in LMFBR. The steam ingress reactivity effects have been studied for 300 MWe and 1000 MWe GCFR designed at General Atomics in US., taking account of the influences of fuel burnup, fuel temperature and the presence of control rods. The calculations have been made basing on the exact perturbation theory in R-Z geometry together with JAERI-Fast 25 group constants set Version 2. In addition, to assess the uncertainties associated with the data and methods, some detailed investigations have been made on the influences of heterogeneous arrangement of fuel pins in a subassembly, and of differences in nuclear data and their processing methods to produce group constants. And also the measurements of the concerned reactivity effects at ZPR-9 have been analysed to understand our predicting accuracy. From this study, the following conclusions were drawn: (1) In the cold clean state at low fuel temperature with no control rods present, the steam ingress reactivity effect is most positive for 1000 MWe GCFR at BOL but is negative for 300 MWe GCFR. The positive reactivity effect increases as the steam density increases. (2) The presence of control rods in the core significantly reduces the large positive reactivity effect for 1000 MWe GCFR mentioned above. (author)

  20. Vision-Aided Autonomous Landing and Ingress of Micro Aerial Vehicles

    Science.gov (United States)

    Brockers, Roland; Ma, Jeremy C.; Matthies, Larry H.; Bouffard, Patrick

    2012-01-01

    Micro aerial vehicles have limited sensor suites and computational power. For reconnaissance tasks and to conserve energy, these systems need the ability to autonomously land at vantage points or enter buildings (ingress). But for autonomous navigation, information is needed to identify and guide the vehicle to the target. Vision algorithms can provide egomotion estimation and target detection using input from cameras that are easy to include in miniature systems.

  1. A numerical and experimental study of water ingression phenomena in melt pool coolability

    International Nuclear Information System (INIS)

    During a postulated severe accident, the core can melt and the melt can fail the reactor vessel. Subsequently, the molten corium can be relocated in the containment cavity forming a melt pool. The melt pool can be flooded with water at the top for quenching it. However, the question that arises is to what extent the water can ingress in the corium melt pool to cool and quench it. To reveal that, a numerical study has been carried out using the computer code MELCOOL. The code considers the heat transfer behaviour in axial and radial directions from the molten pool to the overlaying water, crust generation and growth, thermal stresses built-in the crust, disintegration of crust into debris, natural convection heat transfer in debris and water ingression into the debris bed. To validate the computer code, experiments were conducted in a facility named as core melt coolability (COMECO). The facility consists of a test section (200 mm x 200 mm square cross-section) and with a height of 300 mm. About 14 L of melt comprising of 30% CaO + 70% B2O3 (by wt.) was poured into the test section. The melt was heated by four heaters from outside the test section to simulate the decay heat of corium. The melt was water flooded from the top, and the depth of water pool was kept constant at around 700 mm throughout the experiment. The transient temperature behaviour in the melt pool at different axial and radial locations was measured with 24 K-type thermocouples and the steam flow rate was measured using a vortex flow meter. The melt temperature measurements indicated that water could ingress only up to a certain depth into the melt pool. The MELCOOL predictions were compared with the test data for the temperature distribution inside the molten pool. The code was found to simulate the quenching behaviour and depth of water ingression quite well.

  2. Quantitative NMR monitoring of liquid ingress into repellent heterogeneous layered fabrics

    OpenAIRE

    Bencsik, Martin; Adriaensen, Hans; Brewer, Stuart; McHale, Glen

    2008-01-01

    Fabrics which are water repellent and repellent to other liquids are often constructed using multiple layers of material. Such a construction is preferable to a single layer of a liquid-repellent textile because, under the action of an applied pressure, ingress of a liquid through the first layer can be halted by the second or subsequent layers. In the quantitative investigation of this problem, current techniques provide limited information on the progress and distribution of the liquid as i...

  3. Quantitative NMR monitoring of liquid ingress into repellent heterogeneous layered fabrics

    Science.gov (United States)

    Bencsik, Martin; Adriaensen, Hans; Brewer, Stuart A.; McHale, Glen

    2008-07-01

    Fabrics which are water repellent and repellent to other liquids are often constructed using multiple layers of material. Such a construction is preferable to a single layer of a liquid-repellent textile because, under the action of an applied pressure, ingress of a liquid through the first layer can be halted by the second or subsequent layers. In the quantitative investigation of this problem, current techniques provide limited information on the progress and distribution of the liquid as it ingresses into a fabric. Moreover, many techniques require that the material is delaminated prior to analysis, and cannot be conducted in real time to measure the progress of a liquid through the textile substrate. In this work we demonstrate that unilateral NMR, which allows signal to be collected from a volume of interest in a material residing above the instrument, can be a powerful tool to quantitatively monitor the ingress of a liquid through a layered sample exhibiting pronounced heterogeneities in repellency. A known volume of oil was placed on the top of a model textile sample composed of three 80 μm thick layers. Spatially resolved one dimensional vertical NMR profiles of the system were acquired as a function of the pressure vertically applied to the top of the sample. These profiles show that the absolute liquid volume present in each layer of textile can routinely be measured within 4 min with a spatial resolution of 15 μm. If each individual layer exhibits different repellency to the test liquid, the complexity of the dynamics of the ingress can be investigated in great detail. An elegant application of the unilateral instrument was obtained in which the sensitive volume matched the region of interest of the individual layers of the textile under investigation.

  4. Air

    Science.gov (United States)

    ... house) Industrial emissions (like smoke and chemicals from factories) Household cleaners (spray cleaners, air fresheners) Car emissions (like carbon monoxide) *All of these things make up “particle pollution.” They mostly come from cars, trucks, buses, and ...

  5. Experimental assessment of accident scenarios for the high temperature reactor fuel system

    International Nuclear Information System (INIS)

    The High Temperature Reactor (HTR) is an advanced reactor concept with particular safety features. Fuel elements are constituted by a graphite matrix containing sub-mm-sized fuel particles with TRISO (tri-isotropic) coating designed to provide high fission product retention. Passive safety features of the HTR include a low power density in the core compared to other reactor designs; this ensures sufficient heat transport in a loss of coolant accident scenario. The temperature during such events would not exceed 1600 C, remaining well below the melting point of the fuel. An experimental assessment of the fuel behaviour under severe accident conditions is necessary to confirm the fission product retention of TRISO coated particles and to validate relevant computer codes. Though helium is used as coolant for the HTR system, additional corrosion effects come into play in case of an in-leakage affecting the primary circuit. The experimental scope of the present work focuses on two key aspects associated with the HTR fuel safety. Fission product retention at high temperatures (up to ∝1800 C) is analyzed with the so-called cold finger apparatus (KueFA: Kuehlfinger-Apparatur), while the performance of HTR fuel elements in case of air/steam ingress accidents is assessed with a high temperature corrosion apparatus (KORA: Korrosions-Apparatur). (orig.)

  6. Adaptation of the ASTEC code system to accident scenarios in fusion installations

    International Nuclear Information System (INIS)

    Highlights: ► IRSN has a first version of ASTEC able to model an accident in ITER. ► Models are developed to make possible water/air ingress simulations in the vessel. ► Some thermal-hydraulic calculations in agreement with MELCOR are discussed. -- Abstract: ASTEC is a code system aiming to compute severe accident scenarios and their consequences in nuclear fission Pressurized Water Reactors (PWRs). Its capabilities have been recently extended to address the main accident sequences which may occur in the fusion installations, in particular in ITER. The purpose of this paper is to present a synthesis of the work that has been performed on ASTEC as part of its adaptation to fusion ITER facility, in particular concerning the development of some specific models (dust behavior, jet impaction and wall oxidation), the state of validation of the code and some first calculations for accident transients considered in the basis design. Comparisons with the MELCOR code, selected by ITER for their own safety analysis are provided and show a good agreement between both codes

  7. Air

    International Nuclear Information System (INIS)

    In recent years several regulations and standards for air quality and limits for air pollution were issued or are in preparation by the European Union, which have severe influence on the environmental monitoring and legislation in Austria. This chapter of the environmental control report of Austria gives an overview about the legal situation of air pollution control in the European Union and in specific the legal situation in Austria. It gives a comprehensive inventory of air pollution measurements for the whole area of Austria of total suspended particulates, ozone, volatile organic compounds, nitrogen oxides, sulfur dioxide, carbon monoxide, heavy metals, benzene, dioxin, polycyclic aromatic hydrocarbons and eutrophication. For each of these pollutants the measured emission values throughout Austria are given in tables and geographical charts, the environmental impact is discussed, statistical data and time series of the emission sources are given and legal regulations and measures for an effective environmental pollution control are discussed. In particular the impact of fossil-fuel power plants on the air pollution is analyzed. (a.n.)

  8. Estimation of air to grass - dry and wet deposition rates, velocities, and mass interception factors for iodine for a postulated accidental scenario

    International Nuclear Information System (INIS)

    Measurements of air to grass - dry and wet deposition rates, velocities, and mass interception factors for iodine are sparse in India. Data on these parameters are the basic input for the estimation of radiation dose to the public around a nuclear power plant. We have carried out systematic studies on air to grass - dry and wet deposition rates, velocities, and mass interception factors for iodine for a postulated emergency situation. The main objective of this study was to generate air to grass transfer factors for iodine for the environmental conditions prevailing in Kaiga

  9. Photochemical model evaluation of the ground-level ozone impacts on ambient air quality and vegetation health in the Alberta oil sands region: Using present and future emission scenarios

    Science.gov (United States)

    Vijayaraghavan, Krish; Cho, Sunny; Morris, Ralph; Spink, David; Jung, Jaegun; Pauls, Ron; Duffett, Katherine

    2016-09-01

    One of the potential environmental issues associated with oil sands development is increased ozone formation resulting from NOX and volatile organic compound emissions from bitumen extraction, processing and upgrading. To manage this issue in the Athabasca Oil Sands Region (AOSR) in northeast Alberta, a regional multi-stakeholder group, the Cumulative Environmental Management Association (CEMA), developed an Ozone Management Framework that includes a modelling based assessment component. In this paper, we describe how the Community Multi-scale Air Quality (CMAQ) model was applied to assess potential ground-level ozone formation and impacts on ambient air quality and vegetation health for three different ozone precursor cases in the AOSR. Statistical analysis methods were applied, and the CMAQ performance results met the U.S. EPA model performance goal at all sites. The modelled 4th highest daily maximum 8-h average ozone concentrations in the base and two future year scenarios did not exceed the Canada-wide standard of 65 ppb or the newer Canadian Ambient Air Quality Standards of 63 ppb in 2015 and 62 ppb in 2020. Modelled maximum 1-h ozone concentrations in the study were well below the Alberta Ambient Air Quality Objective of 82 ppb in all three cases. Several ozone vegetation exposure metrics were also evaluated to investigate the potential impact of ground-level ozone on vegetation. The chronic 3-months SUM60 exposure metric is within the CEMA baseline range (0-2000 ppb-hr) everywhere in the AOSR. The AOT40 ozone exposure metric predicted by CMAQ did not exceed the United Nations Economic Commission for Europe (UN/ECE) threshold of concern of 3000 ppb-hr in any of the cases but is just below the threshold in high-end future emissions scenario. In all three emission scenarios, the CMAQ predicted W126 ozone exposure metric is within the CEMA baseline threshold of 4000 ppb-hr. This study outlines the use of photochemical modelling of the impact of an industry (oil

  10. Analysis of the dynamics of hydrogen ingress to secondary sodium after the replacement of the steam generator stages of the BN-600 power unit

    International Nuclear Information System (INIS)

    The article presents the calculation methodology of hydrogen ingress rate into secondary circuit sodium of the BN-600 power unit. The sources and the mechanism of the hydrogen ingress after the replacement of a lot of the PGN-200M steam generator stages within the scope of work on the power unit operation lifetime extension were defined. The hydrogen ingress rate after impending replacements of steam generator stages was estimated

  11. The effect of mixed-bed resin ingress into the Embalse PHTs

    International Nuclear Information System (INIS)

    Embalse NGS is provided four in-line autoclaves for a routine materials surveillance program. Through a cooperative program between the utility management and the Research and Development Branch of CNEA, the routine program was expanded to include Materials Tests according to the on-going R and D programs. The availability of the autoclave facilities and the joint Embalse/R and D program proved very valuable in occasion of the resin ingress into the PHTS due to the collapse of a Johnson strainer on April 9, 1988. The details of the incident have been communicated previously, and it is not the purpose of this presentation to describe the sequence of events on April 9, 1988, and following days. Rather, we present here the results of the materials surveillance program that was adopted to follow the materials behaviour and to check the possible negative impact of the resin ingress. The mixed bed resins were subjected to hydrothermal degradation under high radiation fields (the reactor went into hot shut-down state in two hours and was further cooled in a six hours' interval). Formation of ammonia, carbon dioxide, sulfate, nitrate and chloride are all possible. The long term surveillance program was carried out during the following 400 EFPD, on corrosion coupons provided by AECL and on additional samples prepared in CNEA on original materials from Embalse's PHTS. Comparisons were made of the behaviour of AECL materials ingressed in the Autoclave System in 1983, CNEA materials inserted in 1986, and additional CNEA coupons installed in 1988, after the incident

  12. Uncertainties in the analysis of water ingress accident for the HTGR cores

    International Nuclear Information System (INIS)

    Behaviour of the reactor major physical characteristics during the accident related to the water/steam ingress into the core, resulted from the steam generator (SG) loss of integrity has been analysed on the example of the VGM reactor with the pebble bed core designed in the USSR. The header tube instantaneous double-ended rupture without interaction of the outgoing flows has been considered due to the uncertainties of its failure process. Calculation of water quantity discharged into the core has been made under the following assumptions: 1) Accumulation of water in liquid state in the core is eliminated in as much as the fuel elements and helium temperature exceed water boiling temperature at a pressure of about 5 MPa: 2) Chemical interaction of water with graphite is not taken into account: 3) Moisture sensors fail to be actuated. The calculation results of the water mass variations in the core vs. time as well as reactivity changes caused by water ingress into the core are given in the paper. The need to take into account reactivity changes caused by the front edge of the steam/helium mixture that defines the neutron power increase rate has been shown is the paper. Changes of the reactivity compensation members' efficiency at a steam/water ingress into the core and reflector both in hot and cooled down reactor have been evaluated. The paper carries requirements for experimental investigations intended to prove the adequacy of the reactivity compensation members' efficiency in the accident under consideration. (author). 6 refs, 3 figs

  13. Columnar modelling of nucleation burst evolution in the convective boundary layer – first results from a feasibility study Part III: Preliminary results on physicochemical model performance using two "clean air mass" reference scenarios

    Directory of Open Access Journals (Sweden)

    O. Hellmuth

    2006-01-01

    Full Text Available In Paper I of four papers, a revised columnar high-order model to investigate gas-aerosol-turbulence interactions in the convective boundary layer (CBL was proposed. In Paper II, the model capability to predict first-, second- and third-order moments of meteorological variables in the CBL was demonstrated using available observational data. In the present Paper III, the high-order modelling concept is extended to sulphur and ammonia chemistry as well as to aerosol dynamics. Based on the previous CBL simulation, a feasibility study is performed using two "clean air mass" scenarios with an emission source at the ground but low aerosol background concentration. Such scenarios synoptically correspond to the advection of fresh post-frontal air in an anthropogenically influenced region. The aim is to evaluate the time-height evolution of ultrafine condensation nuclei (UCNs and to elucidate the interactions between meteorological and physicochemical variables in a CBL column. The scenarios differ in the treatment of new particle formation (NPF, whereas homogeneous nucleation according to the classical nucleation theory (CNT is considered. The first scenario considers nucleation of a binary system consisting of water vapour and sulphuric acid (H2SO4 vapour, the second one nucleation of a ternary system additionally involving ammonia (NH3. Here, the two synthetic scenarios are discussed in detail, whereas special attention is payed to the role of turbulence in the formation of the typical UCN burst behaviour, that can often be observed in the surface layer. The intercomparison of the two scenarios reveals large differences in the evolution of the UCN number concentration in the surface layer as well as in the time-height cross-sections of first-order moments and double correlation terms. Although in both cases the occurrence of NPF bursts could be simulated, the burst characteristics and genesis of the bursts are completely different. It is demonstrated

  14. Contaminant ingress into multizone buildings: An analytical state-space approach

    DEFF Research Database (Denmark)

    Parker, Simon; Coffey, Chris; Gravesen, Jens;

    2014-01-01

    The ingress of exterior contaminants into buildings is often assessed by treating the building interior as a single well-mixed space. Multizone modelling provides an alternative way of representing buildings that can estimate concentration time series in different internal locations. A state...... term maximum concentration and exposure in a multizone building in response to a step-change in concentration. These have considerable potential for practical use. The analytical development is demonstrated using a simple two-zone building with an inner zone and a range of existing multizone models...

  15. Pressurizing Behavior on Ingress of Coolant into Pebble Bed of Blanket of Fusion DEMO Reactor

    International Nuclear Information System (INIS)

    Solid breeder blankets are being developed as candidate blankets for the Fusion DEMO reactor in Japan. JAEA is performing the development of the water cooled and helium cooled solid breeder blankets. The blanket utilizes ceramic breeder pebbles and multiplier pebbles beds cooled by high pressure water or high pressure helium in the cooling tubes placed in the blanket box structure. In the development of the blanket, it is very important to incorporate the safety technology as well as the performance improvement on tritium production and energy conversion. In the safety design and technology, coolant ingress in the blanket box structure is one of the most important events as the initiators. Especially the thermal hydraulics in the pebble bed in the case of the high pressure coolant ingress is very important to evaluate the pressure propagation and coolant flow behavior. This paper presents the preliminary results of the pressure loss characteristics by the coolant ingress in the pebble bed. Experiments have been performed by using alumina pebble bed (4 litter maximum volume of the pebble bed) and nitrogen gas to simulate the helium coolant ingress into breeder and multiplier pebble beds. Reservoir tank of 10 liter is filled with 1.0 MPa nitrogen. The nitrogen gas is released at the bottom part of the alumina pebble bed whose upper part is open to the atmosphere. The pressure change in the pebble bed is measured to identify the pressure loss. The measured values are compared with the predicted values by Ergun's equation, which is the correlation equation on pressure loss of the flow through porous medium. By the results of the experiments with no constraint on the alumina pebble bed, it was clarified that the measured value agreed in the lower flow rate. However, in the higher flow rate where the pressure loss is high, the measured value is about half of the predicted value. The differences between the measured values and the predicted values will be discussed from

  16. Do predator-prey relationships on the river bed affect fine sediment ingress?

    Science.gov (United States)

    Mathers, Kate; Rice, Stephen; Wood, Paul

    2016-04-01

    Ecosystem engineers are organisms that alter their physical environment and thereby influence the flow of resources through ecosystems. In rivers, several ecosystem engineers are also important geomorphological agents that modify fluvial sediment dynamics. By altering channel morphology and bed material characteristics, such modifications can affect the availability of habitats for other organisms, with implications for ecosystem health and wider community composition. In this way geomorphological and ecological systems are intimately interconnected. This paper focuses on one element of this intricate abiotic-biotic coupling: the interaction between fine sediment ingress into the river bed and the predator-prey relationships of aquatic organisms living on and in the river bed. Signal crayfish (Pacifastacus leniusculus) have been shown to modify fine sediment fluxes in rivers, but their effect on fine sediment ingress into riverbeds remains unclear. Many macroinvertebrate taxa have adapted avoidance strategies to avoid predation by crayfish, with one example being the freshwater shrimp (Gammarus pulex) which relies on open interstitial spaces within subsurface sediments as a refuge from crayfish predation. Fine sedimentation that fills gravelly frameworks may preclude access to those spaces, therefore leaving freshwater shrimp susceptible to predation. Ex-situ experiments were conducted which sought to examine: i) if freshwater shrimps and signal crayfish, alone and in combination, influenced fine sediment infiltration rates; and ii) whether modifications to substratum composition, specifically the introduction of fine sediment, modified predator-prey interactions. The results demonstrate that crayfish are significant geomorphic agents and that fine sediment ingress rates were significantly enhanced in their presence compared to control conditions or the presence of only freshwater shrimps. The combination of both organisms (i.e. allowing the interaction between

  17. Simulating the impact of urban sprawl on air quality and population exposure in the German Ruhr area. Part II: Development and evaluation of an urban growth scenario

    OpenAIRE

    De Ridder, Koen; Lefebre, Filip; Adriaensen, Stefan; Arnold, Ute; Beckroege, Wolfgang; Bronner, Christine; Damsgaard, Ole; Dostal, Ivo; Dufek, Jiri; Hirsch, Jacky; Int Panis, Luc; Kotek, Zdenek; Ramadier, Thierry; Thierry, Annette; Vermoote, Stijn

    2008-01-01

    The impact of uncontrolled urban growth ('sprawl') on air pollution and associated population exposure is investigated. This is done for the Ruhr area in Germany, by means of a coupled modelling system dealing with land use changes, traffic, meteorology, and atmospheric dispersion and chemistry. In a companion paper [De Ridder, K., Lefebre F., Adriaensen S., Arnold U., Beckroege W., Bronner C., Damsgaard O., Dostal I., Dufek J., Hirsch J., Int Panis L., Kotek Z., Ramadier T., Thierry A., Verm...

  18. Summary of the BIOMOVS A4 scenario: Testing models of the air-pasture-cow milk pathway using Chernobyl fallout data

    International Nuclear Information System (INIS)

    A unique opportunity to test dose assessment models arose after the Chernobyl reactor accident. During the passage of the contaminated plume, concentrations of 131I and 137Cs in air, pasture, and cow's milk were collected at various sites in the northern hemisphere. Afterwards, contaminated pasture and milk samples were analyzed over time. Under the auspices of the Biospheric Model Validation Study (BIOMOVS), data from 13 sites for 131I and 10 sites for 137Cs were used to test model predictions for the air-pasture-cow milk pathway. Calculations were submitted for 23 models, 10 of which were quasi-steady state. The others were time-dependent. Daily predictions and predictions of time-integrated concentration of 131I and 137Cs in pasture grass and milk for six months post-accident were calculated and compared with observed data. Testing against data from several locations over time for several steps in the air-to-milk pathway resulted in a better understanding of important processes and how they should be modeled. This model testing exercise showed both the strengths and weaknesses of the models and revealed the importance of testing all parts of dose assessment models whenever possible. 19 refs., 14 figs., 4 tabs

  19. Perfluorocarbon Tracer Experiments on a 2 km Scale in Manchester Showing Ingress of Pollutants into a Building

    Science.gov (United States)

    Matthews, James; Wright, Matthew; Bacak, Asan; Silva, Hugo; Priestley, Michael; Martin, Damien; Percival, Carl; Shallcross, Dudley

    2016-04-01

    Cyclic perfluorocarbons (PFCs) have been used to measure the passage of air in urban and rural settings as they are chemically inert, non-toxic and have low background concentrations. The use of pre-concentrators and chemical ionisation gas chromatography enables concentrations of a few parts per quadrillion (ppq) to be measured in bag samples. Three PFC tracers were used in Manchester, UK in the summer of 2015 to map airflow in the city and ingress into buildings: perfluomethylcyclohexane (PMCH), perfluoro-2-4-dimethylcyclohexane (mPDMCH) and perfluoro-2-methyl-3-ethylpentene (PMEP). A known quantity of each PFC was released for 15 minutes from steel canisters using pre-prepared PFC mixtures. Release points were chosen to be upwind of the central sampling location (Simon Building, University of Manchester) and varied in distance up to 2.2 km. Six releases using one or three tracers in different configurations and under different conditions were undertaken in the summer. Three further experiments were conducted in the Autumn, to more closely investigate the rate of ingress and decay of tracer indoors. In each experiment, 10 litre samples were made over 30 minutes into Tedlar bags, starting at the same time the as PFC release. Samples were taken in 11 locations chosen from 15 identified areas including three in public parks, three outside within the University of Manchester area, seven inside and five outside of the Simon building and two outside a building nearby. For building measurements, receptors were placed inside the buildings on different floors; outside measurements were achieved through a sample line out of the window. Three of the sample positions inside the Simon building were paired with samplers outside to allow indoor-outdoor comparisons. PFC concentrations varied depending on location and height. The highest measured concentrations occurred when the tracer was released at sunrise; up to 330 ppq above background (11 ppq) of PMCH was measured at the 6

  20. Assessing the effects of different regulatory scenarios on air pollutant emissions generated by fossil fuels: The case of the new Italian energy plan

    International Nuclear Information System (INIS)

    The paper gives a short view of the study aimed at assessing the effect of different regulations on the reduction of emissions of sulphur dioxide, nitrogen oxides, total suspended particles and carbon monoxide which will be generated in Italy by the combustion of fossil fuels, according to the projections of the energy consumptions reported in the National Energy Plan. Overall, twenty regulatory scenarios have been implemented to simulate the evolution of emissions in the years 1995 and 2000 in the main activity sectors: electricity generation, industry, transportation and domestic. On the basis of the results of this simulation a preliminary estimate has been done of the costs associated with the reduction of emissions in the electricity generating sector. (author)

  1. Reactivity Effect Of Steam / Water Ingress in Generation-IV Gas-Cooled Fast Reactor Core

    International Nuclear Information System (INIS)

    This paper presents a static neutronic calculational study of steam/water ingress into a Gas-cooled Fast Reactor (GFR Generation IV) core performed by using three Monte-Carlo codes, namely SERPENT version 1.1-16, KENO-VI module of the SCALE, MCNPX version 2.7.0, and different modern nuclear data libraries, i.e. JEFF-3.1, JEFF-3.1.1 and ENDF/B-VII. The analysis was performed for a wide range of water/steam densities [0 – 1.0 g/cm3] within the core and the neutronic parameters were compared between the different codes and libraries. The obtained results demonstrate that this accidental event would result in a large negative reactivity insertion. The main reason of such core behaviour was found to be an increased neutron absorption rate in the cladding liner made of refractory metals (W and Re) due to the neutron spectrum thermalisation resulting from the steam/water ingress. (author)

  2. Augmin shapes the anaphase spindle for efficient cytokinetic furrow ingression and abscission.

    Science.gov (United States)

    Uehara, Ryota; Kamasaki, Tomoko; Hiruma, Shota; Poser, Ina; Yoda, Kinya; Yajima, Junichiro; Gerlich, Daniel W; Goshima, Gohta

    2016-03-01

    During anaphase, distinct populations of microtubules (MTs) form by either centrosome-dependent or augmin-dependent nucleation. It remains largely unknown whether these different MT populations contribute distinct functions to cytokinesis. Here we show that augmin-dependent MTs are required for the progression of both furrow ingression and abscission. Augmin depletion reduced the accumulation of anillin, a contractile ring regulator at the cell equator, yet centrosomal MTs were sufficient to mediate RhoA activation at the furrow. This defect in contractile ring organization, combined with incomplete spindle pole separation during anaphase, led to impaired furrow ingression. During the late stages of cytokinesis, astral MTs formed bundles in the intercellular bridge, but these failed to assemble a focused midbody structure and did not establish tight linkage to the plasma membrane, resulting in furrow regression. Thus augmin-dependent acentrosomal MTs and centrosomal MTs contribute to nonredundant targeting mechanisms of different cytokinesis factors, which are required for the formation of a functional contractile ring and midbody. PMID:26764096

  3. Suppressing hydrogen ingress during aqueous corrosion of CANDU Zr-2.5 Nb pressure tube material

    International Nuclear Information System (INIS)

    As a result of their special properties, including low neutron cross-section and intrinsic corrosion resistance, Zr alloys are used in the fabrication of nuclear core components, particularly fuel cladding (in most reactor types) and also Zr-2.5 Nb pressure tubes in CANDU trademark (Canada Deuterium Uranium) reactors. Corrosion and H uptake during service can limit the life of these components. Therefore, remedial action may be appropriate to slow the H uptake rate and prolong the working life of these reactor components. This work has explored the possibility of reducing H uptake in pressure tube material by incorporating an inhibiting agent into the corrosion environment. Two approaches have been tested, depositing a thin metallic film on the initial oxide surface and adding an inhibiting agent to the solution. The latter approach appears more practical. Screening experiments were conducted in short-term (∝30 day) exposures in high temperature (340 C) aqueous out-reactor environments, simulating the CANDU trademark heat transport coolant with various chemistries. Compounds tested included aluminum acetate, aluminum nitrate, lithium nitrate, rhodium nitrate and yttrium nitrate. Comparison of results from the aluminum nitrate additives and aluminum acetate additives suggests that the nitrate anion is the effective ingredient for H ingress inhibition. The nitrate anion appears to reduce the rate of H ingress regardless of the associated cation. However, each cation appears to affect the rate of corrosion differently. These cations were found to be incorporated in the oxide film. (authors)

  4. Ingression Progression Complexes Control Extracellular Matrix Remodelling during Cytokinesis in Budding Yeast

    Science.gov (United States)

    Foltman, Magdalena; Molist, Iago; Arcones, Irene; Sacristan, Carlos; Filali-Mouncef, Yasmina; Roncero, Cesar; Sanchez-Diaz, Alberto

    2016-01-01

    Eukaryotic cells must coordinate contraction of the actomyosin ring at the division site together with ingression of the plasma membrane and remodelling of the extracellular matrix (ECM) to support cytokinesis, but the underlying mechanisms are still poorly understood. In eukaryotes, glycosyltransferases that synthesise ECM polysaccharides are emerging as key factors during cytokinesis. The budding yeast chitin synthase Chs2 makes the primary septum, a special layer of the ECM, which is an essential process during cell division. Here we isolated a group of actomyosin ring components that form complexes together with Chs2 at the cleavage site at the end of the cell cycle, which we named ‘ingression progression complexes’ (IPCs). In addition to type II myosin, the IQGAP protein Iqg1 and Chs2, IPCs contain the F-BAR protein Hof1, and the cytokinesis regulators Inn1 and Cyk3. We describe the molecular mechanism by which chitin synthase is activated by direct association of the C2 domain of Inn1, and the transglutaminase-like domain of Cyk3, with the catalytic domain of Chs2. We used an experimental system to find a previously unanticipated role for the C-terminus of Inn1 in preventing the untimely activation of Chs2 at the cleavage site until Cyk3 releases the block on Chs2 activity during late mitosis. These findings support a model for the co-ordinated regulation of cell division in budding yeast, in which IPCs play a central role. PMID:26891268

  5. Defending of IP Spoofing by Ingress Filter in Extended-Inter Domain Packet Key Marking System

    Directory of Open Access Journals (Sweden)

    G.Velmayil

    2013-04-01

    Full Text Available The significance of the DDoS problem and the increased occurrence and strength of attacks has led to the dawn of numerous prevention mechanisms. IP spoofing is most frequently used in denial-of-service attacks. In such attacks, the goal is to flood the victim with overwhelming amounts of traffic, and the attacker does not care about receiving responses to the attack packets. IP spoofing is one of the basic weaknesses in the Internet Protocol to launch the DDOS attack. Each prevention mechanism has some unique advantages and disadvantages over the others. The existing methods become ineffective due to a large number of filters required and they lack in information about where to place the filter. We propose Ingress filter in Extended Inter Domain Packet Key marking system .This paper comprises of two functional blocks namely, Key marking system and filtering blocks. In the marking block, each source is labeled with a key. The key is changed continuously for a certain period of time to provide secured system and is validated at border routers. In the filtering block, spoofed packets are filtered at the border router using Ingress filter to filter beyond periphery routers. The filter placement algorithm clearly put forwards the conditions under which the filter can operate accurately. The accuracy of the proposed systems is validated using Network Simulator (NS-2.

  6. Development of a model to predict fission product behaviour in spherical fuel elements during water ingress events

    International Nuclear Information System (INIS)

    At PBMR gaseous fission product releases from spherical fuel elements under normal conditions are calculated by the code NOBLEG. The ability of NOBLEG to calculate noble gas and halogen release under oxidizing conditions during water ingress was developed. Observations made during the water vapour injection tests performed during the irradiation experiment HFR-K6, were used to determine simple relations that can be used to predict gaseous fission product release from spherical fuel elements under oxidizing conditions caused by small water ingress events, for PBMR operational temperatures. A new model was proposed to explain peculiarities observed during the water injection tests

  7. SR-Site: Oxygen ingress in the rock at Forsmark during a glacial cycle

    International Nuclear Information System (INIS)

    The aim of this report is to assess the possibility for oxygen to be transported by glacial melt-water to canister positions in a final repository for spent nuclear fuel at the proposed location in Forsmark. The approach for this assessment is to combine reactive transport modelling with geological observations of present and historical indications of oxygen ingress. For safety assessment purposes a cautious approach in the modelling is required when estimating the extent of oxygen ingress. In this report, a cautious approach has been applied both in the conceptualisation of the problem and in the choice of input parameters used in the models. Oxygen consuming processes are only neglected in the modelling if they are expected to further decrease the extent of oxygen ingress. Several oxygen consuming processes have been identified, each of which may play an important role in the scavenging of oxygen along recharge flow paths in the rock. These processes include biological pathways with degradation of organic material of ground surface origin, and biotically mediated reactions with reduced rock minerals and with various materials expected to be present in the backfilled repository volume. In the absence of microbes most of these reactions may also follow abiotic pathways. Present day observations show that degradation of organic material is the most powerful oxygen scavenging process. At Forsmark, oxygen is generally depleted within a few metres under present day temperate conditions. Although biological activity is likely to exist also during different phases of a glaciation, large uncertainties exist regarding e.g. the population growth dynamics, the biotic reaction rates and the availability of organic material under the highly varying conditions expected. Microbial activity and degradation of organic material is therefore pessimistically neglected in the calculations in this report. In the absence of organic material, ferrous iron present in minerals in the rock

  8. SR-Site: Oxygen ingress in the rock at Forsmark during a glacial cycle

    Energy Technology Data Exchange (ETDEWEB)

    Sidborn, Magnus (Kemakta Konsult AB (Sweden)); Sandstroem, Bjoern (WSP Sverige AB (Sweden)); Tullborg, Eva-Lena (Terralogica AB (Sweden)); Salas, Joaquin; Maia, Flavia; Delos, Anne; Molinero, Jorge (Amphos21 (Spain)); Hallbeck, Lotta; Pedersen, Karsten (Microbial Analytics Sweden AB (Sweden))

    2010-11-15

    The aim of this report is to assess the possibility for oxygen to be transported by glacial melt-water to canister positions in a final repository for spent nuclear fuel at the proposed location in Forsmark. The approach for this assessment is to combine reactive transport modelling with geological observations of present and historical indications of oxygen ingress. For safety assessment purposes a cautious approach in the modelling is required when estimating the extent of oxygen ingress. In this report, a cautious approach has been applied both in the conceptualisation of the problem and in the choice of input parameters used in the models. Oxygen consuming processes are only neglected in the modelling if they are expected to further decrease the extent of oxygen ingress. Several oxygen consuming processes have been identified, each of which may play an important role in the scavenging of oxygen along recharge flow paths in the rock. These processes include biological pathways with degradation of organic material of ground surface origin, and biotically mediated reactions with reduced rock minerals and with various materials expected to be present in the backfilled repository volume. In the absence of microbes most of these reactions may also follow abiotic pathways. Present day observations show that degradation of organic material is the most powerful oxygen scavenging process. At Forsmark, oxygen is generally depleted within a few metres under present day temperate conditions. Although biological activity is likely to exist also during different phases of a glaciation, large uncertainties exist regarding e.g. the population growth dynamics, the biotic reaction rates and the availability of organic material under the highly varying conditions expected. Microbial activity and degradation of organic material is therefore pessimistically neglected in the calculations in this report. In the absence of organic material, ferrous iron present in minerals in the rock

  9. 36 CFR 14.5 - Nature of interest granted; settlement on right-of-way; rights of ingress and egress.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Nature of interest granted; settlement on right-of-way; rights of ingress and egress. 14.5 Section 14.5 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR RIGHTS-OF-WAY Nature of Interest § 14.5...

  10. Design and test of reliable high strength ingressive polycrystalline silicon microgripper arrays

    International Nuclear Information System (INIS)

    We present the design and validation of a micromachined gripper array that enables reliable transmission of forces of at least 14 mN. The gripper is constructed with polycrystalline silicon (polysilicon), a brittle material, and is compatible with polysilicon surface micromachining. Two ingressive snap-and-lock array designs are presented. After developing design guidelines, it is shown that the first gripper array is functional. However, a risk remains that the gripper array rather than the tensile bar that it grips in its intended application fails. Therefore, an improved geometry is designed and it is shown that it is robust with respect to failure. Scanning confocal Raman imaging directly confirms that the local peak tensile stresses in the robust gripper array are approximately 50% of the lower bound material strength, and also resolves a 25% stress variation across the array. (paper)

  11. Design and test of reliable high strength ingressive polycrystalline silicon microgripper arrays

    Science.gov (United States)

    Hazra, S. S.; Beuth, J. L.; Myers, G. A.; DelRio, F. W.; de Boer, M. P.

    2015-01-01

    We present the design and validation of a micromachined gripper array that enables reliable transmission of forces of at least 14 mN. The gripper is constructed with polycrystalline silicon (polysilicon), a brittle material, and is compatible with polysilicon surface micromachining. Two ingressive snap-and-lock array designs are presented. After developing design guidelines, it is shown that the first gripper array is functional. However, a risk remains that the gripper array rather than the tensile bar that it grips in its intended application fails. Therefore, an improved geometry is designed and it is shown that it is robust with respect to failure. Scanning confocal Raman imaging directly confirms that the local peak tensile stresses in the robust gripper array are approximately 50% of the lower bound material strength, and also resolves a 25% stress variation across the array.

  12. Water ingress into a casein film quantified using time-resolved neutron imaging.

    Science.gov (United States)

    Metwalli, E; Hermes, H E; Calzada, E; Kulozik, U; Egelhaaf, S U; Müller-Buschbaum, P

    2016-03-01

    The migration of water into a casein film was probed with neutron radiography. From the neutron transmission images, the evolution of the water saturation profiles was extracted. The results indicate that the water influx is dominated by imbibition but also contains a diffusional component. The time dependence of the water ingress was quantified using a diffusion-like equation previously also applied to imbibition. A water transport coefficient D = 0.9 × 10(-9) m(2) s(-1) was found. This value and direct observation of the images indicate that the time taken for a typical adhesive casein-based layer to become saturated with water is of the order of hours. PMID:26862596

  13. Finite Element Reliability Analysis of Chloride Ingress into Reinforced Concrete Structures

    DEFF Research Database (Denmark)

    Frier, Christian; Sørensen, John Dalsgaard

    2007-01-01

    For many reinforced concrete structures corrosion of the reinforcement is an important problem since it can result in maintenance and repair actions. Further, a reduction of the load-bearing capacity can occur. In the present paper the Finite Element Reliability Method (FERM) is employed for...... obtaining the probability of exceeding a critical chloride concentration level at the reinforcement bars, both using Monte Carlo Simulation (MCS) and the First Order Reliability Method (FORM). The chloride ingress is modelled by the Finite Element Method (FEM) and the diffusion coefficient, surface chloride...... concentration and reinforcement cover depth are modelled by stochastic fields, which are discretized using the Expansion Optimum Linear Estimation (EOLE) approach. The response gradients needed for FORM analysis are derived analytically using the Direct Differentiation Method (DDM). As an example, a bridge pier...

  14. Influence of heat treatment on hydrogen ingress into V-4Cr-4Ti alloy

    Science.gov (United States)

    Hayakawa, Ryo; Hatano, Yuji; Fukumoto, Ken-ichi; Matsui, Hideki; Watanabe, Kuniaki

    2004-08-01

    Specimens of V-4Cr-4Ti alloy were heated at 1273 K in vacuum, and the influence of this heat treatment on H 2 absorption was examined at temperatures from 523 to 1023 K under the presence of water vapor of 10 -5 Pa. The rate of H 2 absorption was significantly reduced by the heat treatment in the temperature range examined. Such reduction in the absorption rate was ascribed to the surface segregation of Ti and increase in surface oxygen coverage caused by preferential oxidation of segregating Ti by water vapor. Comparison with data reported by other researchers [J. Nucl. Mater. 233-237 (1996) 376; Fusion Technol. 34 (1998) 868; J. Nucl. Mater. 233-237 (1996) 510] indicated the strong barrier effect of Ti oxide against hydrogen ingress.

  15. Resistance of a novel root canal sealer to bacterial ingress in vitro.

    Science.gov (United States)

    Padachey, N; Patel, V; Santerre, P; Cvitkovitch, D; Lawrence, H P; Friedman, S

    2000-11-01

    A dentin-bonding root canal sealer (ZUT) has been developed, consisting of an experimental glass ionomer cement (KT-308) and an antimicrobial silver-containing zeolite (0.2% by weight). This in vitro study evaluated the ability of ZUT used with or without gutta-percha, to resist bacterial ingress of Enterococcus faecalis over a period of 90 days. Canals of 80 single-rooted teeth were prepared with apical patency and filled as follows (n = 10): KT-308 alone; KT-308 with a single gutta-percha cone (SCGP); ZUT alone; ZUT with SCGP; AH26 alone; AH26 with SCGP; positive control-no root canal filling; and negative control-no root canal filling, with the apices of this group sealed with C&B Metabond cement. Teeth were coated with nail polish except for the apical 2 mm, and each tooth was sealed in a 4-ml glass vial, with an 18-gauge needle inserted through the vial cover and bonded into the pulp chamber with C&B Metabond cement. After sterilization with 2.5 Mrad gamma-radiation, Brain Heart Infusion broth with phenol red was injected into each vial. An inoculum of E. faecalis was pipetted through the needle into the pulp chamber every 5 days, and the broth was monitored daily for color change and turbidity. When change occurred, the broth was cultured for growth of E. faecalis. Kaplan-Meier survival analysis and the log-rank test revealed no significant differences among the three sealers used. The presence of gutta-percha, however, significantly improved resistance to bacterial ingress through obturated root canals (X, p < 0.05). Under the conditions of this study, the hypothesized advantage of ZUT (0.2% zeolite) was not demonstrated. PMID:11469295

  16. Towards a new scenary for research assessment: the institutional repository (AIR of Milan University Verso un nuovo scenario per la valutazione della ricerca: l'Archivio Istituzionale della Ricerca (AIR dell'Università di Milano

    Directory of Open Access Journals (Sweden)

    Paola Galimberti

    2010-06-01

    Full Text Available The aim of this work is to report about the unconventional use of an institutional repository, that has been used as data source to assess the scientific production and productivity within the Departments of the Faculty of Letters at the University of Milan.The analysis of the results of the pilot shows that the archive and the data manager are a valid instrument to aggregate and analyze large quantities of bibliographic metadata, so the pilot can be extended to the whole university.A comparison with other universities is difficult since the use of institutional respositories is not so widespread, and there is no security on the coverage and the comprehensiveness of the data inside them. To conclude, there is a strong necessity to widen the presence and the usage of institutional repositories, according to the Recommendations of the Conference of the Rectors of Italian Universities (CRUI, and to update methodologies and processes of evaluation considering new models of production, fruition, and dissemination of scientific outputs. Moreover, the open access approach not only widens the potentialities of an easier access to information, but modifies the fruition of the information itself.The evaluative scenario must adapt to the new circumstances, as well as web circulation of the information has modified the measurability of contents with respect to the results in the publications themselves.Il presente lavoro esamina l'esperienza dell'utilizzo dell'archivio istituzionale dell'Università degli Studi di Milano come fonte di informazione per la valutazione interna dei prodotti della ricerca dei Dipartimenti della Facoltà di Lettere e Filosofia.  Attraverso l'analisi dei risultati dell'esercizio pilota, l'archivio e il sistema di elaborazione di dati in esso contenuti si sono rivelati un ottimo strumento per l'aggregazione e l'analisi di grandi quantità di metadati bibliografici qualitativamente affidabili e utilizzabili per esercizi di

  17. Magnitude and reactivity consequences of moisture ingress into the modular High-Temperature Gas-Cooled Reactor core

    International Nuclear Information System (INIS)

    Inadvertent admission of moisture into the primary system of a modular high-temperature gas-cooled reactor has been identified in US Department of Energy-sponsored studies as an important safety concern. The work described here develops an analytical methodology to quantify the pressure and reactivity consequences of steam-generator tube rupture and other moisture-ingress-related incidents. Important neutronic and thermohydraulic processes are coupled with reactivity feedback and safety and control system responses. The rate and magnitude of steam buildup are found to be dominated by major system features such as break size compared with safety valve capacity and reliability and less sensitive to factors such as heat transfer coefficients. The results indicate that ingress transients progress at a slower pace than previously predicted by bounding analyses, with milder power overshoots and more time for operator or automatic corrective actions

  18. Exposure scenarios for workers

    NARCIS (Netherlands)

    Marquart, H.; Northage, C.; Money, C.

    2007-01-01

    The new European chemicals legislation REACH (Registration, Evaluation, Authorisation and restriction of Chemicals) requires the development of Exposure Scenarios describing the conditions and risk management measures needed for the safe use of chemicals. Such Exposure Scenarios should integrate con

  19. A role for very-long-chain fatty acids in furrow ingression during cytokinesis in Drosophila spermatocytes

    OpenAIRE

    Szafer-Glusman, Edith; Giansanti, Maria Grazia; Nishihama, Ryuichi; Bolival, Benjamin; Pringle, John; Gatti, Maurizio; Fuller, Margaret T.

    2008-01-01

    Cell shape and membrane remodeling rely on regulated interactions between the lipid bilayer and cytoskeletal arrays at the cell cortex. During cytokinesis, animal cells build an actomyosin ring anchored to the plasma membrane at the equatorial cortex. Ring constriction coupled to plasma membrane ingression separates the two daughter cells [1]. Plasma-membrane lipids influence membrane biophysical properties such as membrane curvature and elasticity and play an active role in cell function [2]...

  20. Improvement of TRAC-BF1 code to analyze the Ingress of Coolant Event (ICE)

    International Nuclear Information System (INIS)

    JAERI is performing the Ingress of Coolant Event (ICE) preliminary experiment as one of the technology R and D tasks for the International Thermonuclear Experimental Reactor (ITER). The Transient Reactor Analysis Code (TRAC) was improved and arranged as the ICE experimental analysis code. The TRAC-BF1 code was originally developed for the thermal hydraulics safety analysis of the boiling water reactor (BWR) at the Idaho National Engineering Laboratory (INEL) in USA. We partially modified the code to be applicable for the ICE analysis such as adding the heat transfer model in the VESSEL element plane surface, individual appointment of thermal transfer calculation mesh in VESSEL element. Moreover, the IPLOT program and the GCONV program was introduced to the engineering workstation (EWS) for plotting calculation outputs of TRAC-BF1 code. This paper describes a summary of the improved TRAC-BF1 code, and verification results of the modification of the TRAC-BF1 code, and ICE experimental analyzed result. (author)

  1. Contaminant ingress into multizone buildings: An analytical state-space approach

    KAUST Repository

    Parker, Simon

    2013-08-13

    The ingress of exterior contaminants into buildings is often assessed by treating the building interior as a single well-mixed space. Multizone modelling provides an alternative way of representing buildings that can estimate concentration time series in different internal locations. A state-space approach is adopted to represent the concentration dynamics within multizone buildings. Analysis based on this approach is used to demonstrate that the exposure in every interior location is limited to the exterior exposure in the absence of removal mechanisms. Estimates are also developed for the short term maximum concentration and exposure in a multizone building in response to a step-change in concentration. These have considerable potential for practical use. The analytical development is demonstrated using a simple two-zone building with an inner zone and a range of existing multizone models of residential buildings. Quantitative measures are provided of the standard deviation of concentration and exposure within a range of residential multizone buildings. Ratios of the maximum short term concentrations and exposures to single zone building estimates are also provided for the same buildings. © 2013 Tsinghua University Press and Springer-Verlag Berlin Heidelberg.

  2. Theoretical and experimental studies of crossflow minichannel heat exchanger subjected to external heat ingress

    International Nuclear Information System (INIS)

    The effect of heat in-leak, an unavoidable phenomenon occurring due to the temperature difference between the system and its surroundings, has been studied for two-stream crossflow minichannel heat exchangers with unmixed fluids. Assuming that the amount of heat in-leak is known, an analytical expression for the normalised temperature difference between hot and cold fluids has been derived in terms of dimensionless parameters. The analytical results, in conjugation with the area partitioning of crossflow heat exchanger both in x and y directions, have been used for predicting the outlet fluid temperatures. On the experimental part, one of the end plates in a crossflow-type multistream, minichannel heat exchanger has been subjected to deliberate external heat input given electrically. The variation in the exit fluid temperatures has been recorded as a function of this external heat in-leak entering the exchanger through one of its outer surfaces. Experimental data obtained is employed to validate the fluid exit temperatures predicted by the developed model under the same conditions of external heat ingress. - Highlights: • Theoretical model of crossflow heat exchanger with known ambient heat leak amount. • Numerical technique of partitioning exchanger into smaller segments. • Experimental validation of model by testing of crossflow minichannel heat exchanger

  3. The world in scenarios

    International Nuclear Information System (INIS)

    As an introduction to this special issue 'Worlds of difference: Scenarios's for the economy, energy and the environment 1990-2015', an outline is given of the future of the world and the Netherlands, based on four scenarios. These scenarios are published in 'Scanning the future' in May 1992 by the CPB, the Dutch Central Planning Bureau. The Global Shift (GS) scenario is characterized by a very dynamic technological development, the free market perspective, strong economic growth in the Asian economies, and a relative economic regression in Western Europe. In the European Renaissance (ER) scenario the technological development is less dynamic and more gradual than in the GS scenario. The Balanced Growth (BG) scenario is dominated by a sustainable economic development and a strong technological dynamic development. The Global Crisis (GC) scenario shows a downward spiral in many areas, stagnating developments and fragile economies as results of the trends in the eighties. The first three scenarios are elaborated for the Netherlands. Also attention is paid to the aims and meaning of long-term scenarios. 2 figs., 2 tabs., 3 refs

  4. Review of Climate Scenarios

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Concept and application requirements of climate scenarios were introduced briefly,meanwhile,progresses on theoretical and applied aspects of climate scenarios creation techniques were discussed systematically.Two methods on predicted regional climate changing scenarios,elevating the spatial resolution output and downscaling method,could retrieve the insufficiencies respectively.And the statistical-dynamical downscaling method will be an important developing trend in the developing of downscaling techniques.

  5. Scenarios for nature development

    NARCIS (Netherlands)

    Harms, W.B.

    1995-01-01

    A procedure in backcasting scenarios is presented. Two case-studies differing in scale illustrate the differences in ecological contribution to plan design and to plan evaluation. Scenarios for nature development are presented for both case-studies, based on ecological objectives and spatial strateg

  6. Rail crash demonstration scenarios

    International Nuclear Information System (INIS)

    The paper describes the manner in which the rail crash scenario was selected for public demonstration. A simplified risk assessment led to the short listing of three contender scenarios involving a drop from a high level, a crash into an abutment and the crash of a train into a stationary flask. Predictive work led to the final selection of the train crash. (author)

  7. Integrative Scenario Development

    Directory of Open Access Journals (Sweden)

    Joerg A. Priess

    2014-03-01

    Full Text Available Scenarios are employed to address a large number of future environmental and socioeconomic challenges. We present a conceptual framework for the development of scenarios to integrate the objectives of different stakeholder groups. Based on the framework, land-use scenarios were developed to provide a common base for further research. At the same time, these scenarios assisted regional stakeholders to bring forward their concerns and arrive at a shared understanding of challenges between scientific and regional stakeholders, which allowed them to eventually support regional decision making. The focus on the integration of views and knowledge domains of different stakeholder groups, such as scientists and practitioners, required rigorous and repeated measures of quality control. The application of the integrative concept provided products for both stakeholder groups, and the process of scenario development facilitated cooperation and learning within both the scientist and practitioner groups as well as between the two groups.

  8. Learning Through Scenario Planning

    DEFF Research Database (Denmark)

    Balarezo, Jose

    This project investigates the uses and effects of scenario planning in companies operating in highly uncertain and dynamic environments. Whereas previous research on scenario planning has fallen short of providing sufficient evidence of its mechanisms and effects on individual or organizational...... level variables, this research corrects this void by investigating the dynamics of organizational learning through the lenses of a corporate scenario planning process. This enhances our scientific understanding of the role that scenario planning might play in the context of organizational learning and...... counterintuitive ways in which an organization uses scenario planning in balancing the tension between exploration and exploitation. Moreover, this research proposes two novel mechanisms designed to enhance learning flows. At the core of this dissertation are four papers which in combination solidify our...

  9. Experimental assessment of accident scenarios for the high temperature reactor fuel system

    International Nuclear Information System (INIS)

    The High Temperature Reactor (HTR) is characterized by an advanced design with passive safety features. Fuel elements are constituted by a graphite matrix containing sub-mm-sized fuel particles with TRi-ISOtropic (TRISO) coating, designed to provide high fission product retention. During a loss of coolant accident scenario in a HTR the maximum temperature is foreseen to be in the range of 1,600 to 1,650 C, remaining well below the melting point of the fuel. Two key aspects associated with the safety of HTR fuel are assessed in this paper: fission product retention at temperatures up to 1,800 C is analyzed with the Cold Finger Apparatus (KueFA) while the behaviour of HTR-relevant fuel materials in an oxidizing environment is studied with the Corrosion Apparatus KORA. The KueFA is used to observe the combined effects of Depressurization and LOss of Forced Circulation (DLOFC) accident scenarios on HTR fuel. Originally designed at the Forschungszentrum Juelich (FZJ), an adapted KueFA operates on irradiated fuel in hot cell at JRC-ITU. A fuel pebble is heated in helium atmosphere for several hundred hours, mimicking accident temperatures up to 1,800 C and realistic temperature transients. Nongaseous volatile fission products released from the fuel condense on a water cooled stainless steel plate dubbed 'Cold Finger'. Exchanging plates frequently during the experiment and analyzing plate deposits by means of High Purity Germanium (HPGe) gamma spectroscopy allows a reconstruction of the fission product release as a function of time and temperature. To achieve a good quantification of the release, a careful calibration of the setup is necessary and a collimator needs to be used in some cases. The analysis of condensation plates from recent KueFA tests shows that fission product release quantification is possible at high and low activity levels. Another relevant HTR accident scenario is air ingress into the reactor vessel as a consequence of a DLOFC incident. In case of

  10. Mars base buildup scenarios

    International Nuclear Information System (INIS)

    Two surface base build-up scenarios are presented in order to help visualize the mission and to serve as a basis for trade studies. In the first scenario, direct manned landings on the Martian surface occur early in the missions and scientific investigation is the main driver and rationale. In the second scenario, early development of an infrastructure to exploite the volatile resources of the Martian moons for economic purposes is emphasized. Scientific exploration of the surface is delayed at first, but once begun develops rapidly aided by the presence of a permanently manned orbital station

  11. Pharmaceutical container/closure integrity. IV: Development of an indirect correlation between vacuum decay leak measurement and microbial ingress.

    Science.gov (United States)

    Nguyen, L T; Muangsiri, W; Schiere, R; Guazzo, D K; Kirsch, L E

    1999-01-01

    The rational development of a physical test method to evaluate the microbial barrier properties of sterile containers necessitates its correlation to microbiological exclusion. This can be accomplished by direct or indirect correlation. In the former, the proposed physical test is directly compared to microbial challenges using appropriate test units that stimulate container leaks at both high and low probabilities of microbial ingress. Previous work has demonstrated the development of a direct correlation using helium leak rate methods and microbial immersion challenges. An indirect correlation can be established by comparing the proposed physical method to well-defined leakage standards that represent various known levels of microbial ingress. Thus the quality assurance properties of a physical test method can be established by comparison to another physical test method that has been previously characterized. This approach has the distinct advantages of being faster, quantitatively rigorous, and less subject to the vicissitudes, of microbial testing. This approach was demonstrated by comparing the helium leak rate method to vacuum decay testing. Additionally it was demonstrated that vacuum decay testing was a fast and reproducible method for detecting leaks of about 1 to 2 mm. Leaks were simulated by affixing micropipettes into glass vials. PMID:10754714

  12. In-reactor Hydrogen/Deuterium ingress in Zr-2.5Nb pressure tubes and their measurement in sliver metallic samples

    International Nuclear Information System (INIS)

    Deuterium (D)/Hydrogen (H) ingress in pressure tubes (PTs) of operating PHWRs beyond solubility limit will lead to deuteride/hydride precipitation and may result in delayed hydride cracking. In-reactor H/D ingress in PTs, is periodically monitored by measuring the H/D-content in the sliver metallic samples scraped from selected PTs during their service life. This paper describes some radio analytical works on sliver samples from PTs of some of the reactors of Nuclear Power Corporation of India Limited (NPCIL). (author)

  13. SCENARIO PLANNING AS LEARNING

    Directory of Open Access Journals (Sweden)

    Antonio Lourenço Junior

    2010-10-01

    Full Text Available Scenario Planning has been increasingly used, from its introduction to the decision process as effective tools to test decisions, and improve performance in a dynamic environment (Chermack, 2005. The purpose of this article is to demonstrate the potential of an experimental Scenario Planning Model to mobilize, encourage and add more content to the organization’s decision making process – mainly with respect to Strategic Plans of two governmental institutions, a pharmaceutical company and a technology education foundation.  This study describes the application stages of a hybrid scenario-planning model – herein referred to as Planning as Learning – via action-research, showing the scenarios resulting from the experiment and describes the main results of an assessment of such practice. In order to do that, two well-established Scenario Planning models (Prospective school and Shell’s model were analyzed. They were used as a reference for the proposition and application of an experimental model in the two study objects. A questionnaire was used to assess the technique impact. It was possible to obtain high levels of reliability. In-depth interviews were also conducted with the participants. At the end, the results confirmed the model efficiency as a basis for decision making in the competitive environment in which the two institutions are inserted, also to encourage the learning process as a group, as observed throughout the work.

  14. Scenarios and innovative systems

    International Nuclear Information System (INIS)

    The purpose of this workshop is to present to the GEDEON community the scenarios for the deployment of innovative nuclear solutions. Both steady state situations and possible transitions from the present to new reactors and fuel cycles are considered. Innovative systems that satisfy improved natural resource utilization and waste minimization criteria will be described as well as the R and D orientations of various partners. This document brings together the transparencies of 17 communications given at this workshop: general policy for transmutation and partitioning; Amster: a molten salt reactor (MSR) concept; MSR capabilities; potentials and capabilities of accelerator driven systems (ADS); ADS demonstrator interest as an experimental facility; innovative systems: gas coolant technologies; Pu management in EPR; scenarios with thorium fuel; scenarios at the equilibrium state; scenarios for transition; partitioning and specific conditioning; management of separated radio-toxic elements; European programs; DOE/AAA (Advanced Accelerator Applications) program; OECD scenario studies; CEA research programs and orientations; partitioning and transmutation: an industrial point of view. (J.S.)

  15. Small-Scale Water Ingression and Crust Strength Tests (SSWICS) SSWICS-6 test data report : thermal hydraulic results, Rev. 0.

    Energy Technology Data Exchange (ETDEWEB)

    Lomperski, S.; Farmer, M. T.; Kilsdonk, D.; Aeschlimann, B. (Nuclear Engineering Division)

    2011-06-28

    The Melt Attack and Coolability Experiments (MACE) program at Argonne National Laboratory addressed the issue of the ability of water to cool and thermally stabilize a molten core/concrete interaction (MCCI) when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the melt to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to melt quenching. However, due to the integral nature of these tests, several questions regarding the crust freezing behavior could not be adequately resolved. These questions include: (1) To what extent does water ingression into the crust increase the melt quench rate above the conduction-limited rate and how is this affected by melt composition and system pressure? (2) What is the fracture strength of the corium crust when subjected to a thermal-mechanical load and how does it depend upon the melt composition? A series of separate-effects experiments are being conducted to address these issues. The first employs an apparatus designed to measure the quench rate of a pool of corium ({approx} {phi} 30 cm; up to 20 cm deep). The main parameter to be varied in these quench tests is the melt composition since it is thought to have a critical influence on the crust cracking behavior which, in turn, alters quench rate. The issue of crust strength is being addressed with a second apparatus designed to mechanically load the crust produced by the quench tests. This apparatus measures the fracture strength of the crust while it is either at room temperature or above, the latter state being achieved with a heating element placed below the crust. The two apparatuses used to measure the melt quench rate and crust strength are jointly referred to as SSWICS (Small-Scale Water Ingression and Crust Strength). This report describes results of the sixth water ingression test, designated SSWICS-6. This test

  16. Small-Scale Water Ingression and Crust Strength Tests (SSWICS) SSWICS-6 test data report: thermal hydraulic results, Rev. 0

    International Nuclear Information System (INIS)

    The Melt Attack and Coolability Experiments (MACE) program at Argonne National Laboratory addressed the issue of the ability of water to cool and thermally stabilize a molten core/concrete interaction (MCCI) when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the melt to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to melt quenching. However, due to the integral nature of these tests, several questions regarding the crust freezing behavior could not be adequately resolved. These questions include: (1) To what extent does water ingression into the crust increase the melt quench rate above the conduction-limited rate and how is this affected by melt composition and system pressure? (2) What is the fracture strength of the corium crust when subjected to a thermal-mechanical load and how does it depend upon the melt composition? A series of separate-effects experiments are being conducted to address these issues. The first employs an apparatus designed to measure the quench rate of a pool of corium (∼ φ 30 cm; up to 20 cm deep). The main parameter to be varied in these quench tests is the melt composition since it is thought to have a critical influence on the crust cracking behavior which, in turn, alters quench rate. The issue of crust strength is being addressed with a second apparatus designed to mechanically load the crust produced by the quench tests. This apparatus measures the fracture strength of the crust while it is either at room temperature or above, the latter state being achieved with a heating element placed below the crust. The two apparatuses used to measure the melt quench rate and crust strength are jointly referred to as SSWICS (Small-Scale Water Ingression and Crust Strength). This report describes results of the sixth water ingression test, designated SSWICS-6. This test investigated

  17. Classification of Emergency Scenarios

    CERN Document Server

    Muench, Mathieu

    2011-01-01

    In most of today's emergency scenarios information plays a crucial role. Therefore, information has to be constantly collected and shared among all rescue team members and this requires new innovative technologies. In this paper a classification of emergency scenarios is presented, describing their special characteristics and common strategies employed by rescue units to handle them. Based on interviews with professional firefighters, requirements for new systems are listed. The goal of this article is to support developers designing new systems by providing them a deeper look into the work of first responders.

  18. Scenario group summary

    International Nuclear Information System (INIS)

    The scenario is given which provides a plausible sequence of events for ISABELLE from FY 1980 to 1990. No doubt reality will be quite different. The scenario is based on the construction schedule of the 1976 proposal. Assembly and testing of the accelerator will occur until the end of FY 1983, and the next six years will provide pp interactions for the initial high energy physics research. By 1990 any temporary conditions associated with start-up of ISABELLE should be a thing of the past and all experimental capabilities fully utilized

  19. Stochastic Simulation of Chloride Ingress into Reinforced Concrete Structures by Means of Multi-Dimensional Gaussian Random Fields

    DEFF Research Database (Denmark)

    Frier, Christian; Sørensen, John Dalsgaard

    2005-01-01

    For many reinforced concrete structures corrosion of the reinforcement is an important problem since it can result in expensive maintenance and repair actions. Further, a significant reduction of the load-bearing capacity can occur. One mode of corrosion initiation occurs when the chloride content...... around the reinforcement exceeds a critical threshold value. In the present paper FERM (the Finite Element Reliability Method) is employed for obtaining the probability of exceeding a critical chloride concentration level at the reinforcement bars using MCS (Monte Carlo Simulation). The chloride ingress...... is modeled by a 2-dimensional diffusion process by FEM (Finite Element Method) and the diffusion coefficient, surface chloride concentration and reinforcement cover depth are modeled by multidimensional stochastic fields, which are discretized using the EOLE (Expansion Optimum Linear Estimation...

  20. Emergency exercise scenario tools

    International Nuclear Information System (INIS)

    Nuclear power plant emergency exercises require a realistically presented accident situation which includes various aspects: plant process, radioactivity, radiation, weather and people. Experiences from nuclear power plant emergency exercises show that preparing accident scenarios even for relatively short exercises is tedious. In the future modern computer technology and past experience could be used for making exercise planning more effective. (au)

  1. Emergency exercise scenario tools

    Energy Technology Data Exchange (ETDEWEB)

    Sjoeblom, K

    1998-03-01

    Nuclear power plant emergency exercises require a realistically presented accident situation which includes various aspects: plant process, radioactivity, radiation, weather and people. Experiences from nuclear power plant emergency exercises show that preparing accident scenarios even for relatively short exercises is tedious. In the future modern computer technology and past experience could be used for making exercise planning more effective. (au)

  2. An economically reliable scenario

    International Nuclear Information System (INIS)

    Mister Benjamin Dessus, director of the Ecotech programme at the Cnrs and author of the Noe scenario, describes his propositions for energy prospective, supported by an economic analysis. He advocates the energy diversification and the use of renewable energies. (N.C.). 1 ref., 1 tab

  3. Biomass Scenario Model

    Energy Technology Data Exchange (ETDEWEB)

    2015-09-01

    The Biomass Scenario Model (BSM) is a unique, carefully validated, state-of-the-art dynamic model of the domestic biofuels supply chain which explicitly focuses on policy issues, their feasibility, and potential side effects. It integrates resource availability, physical/technological/economic constraints, behavior, and policy. The model uses a system dynamics simulation (not optimization) to model dynamic interactions across the supply chain.

  4. Demand scenarios, worldwide

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, A. [Massachusetts Inst. of Technology, Center for Technology, Policy and Industrial Development and the MIT Joint Program on the Science and Policy of Global Change, Cambridge, MA (United States)

    1996-11-01

    Existing methods are inadequate for developing aggregate (regional and global) and long-term (several decades) passenger transport demand scenarios, since they are mainly based on simple extensions of current patterns rather than causal relationships that account for the competition among transport modes (aircraft, automobiles, buses and trains) to provide transport services. The demand scenario presented in this paper is based on two empirically proven invariances of human behavior. First, transport accounts for 10 to 15 percent of household total expenditures for those owning an automobile, and around 5 percent for non-motorized households on average (travel money budget). Second, the mean time spent traveling is approximately one hour per capita per day (travel time budget). These two budgets constraints determine the dynamics of the scenario: rising income increases per capita expenditure on travel which, in turn, increase demand for mobility. Limited travel time constraints travelers to shift to faster transport systems. The scenario is initiated with the first integrated historical data set on traffic volume in 11 world regions and the globe from 1960 to 1990 for all major modes of motorized transport. World average per capita traffic volume, which was 1,800 kilometers in 1960 and 4,2090 in 1990, is estimated to rise to 7,900 kilometers in 2020 - given a modest average increase in Gross World Product of 1.9% per year. Higher economic growth rates in Asian regions result in an increase in regional per capita traffic volume up to a factor of 5.3 from 1990 levels. Modal splits continue shifting to more flexible and faster modes of transport. At one point, passenger cars can no longer satisfy the increasing demand for speed (i.e. rising mobility within a fixed time budget). In North America it is estimated that the absolute traffic volume of automobiles will gradually decline starting in the 2010s. (author) 13 figs., 6 tabs., 35 refs.

  5. Ontario demand response scenarios

    International Nuclear Information System (INIS)

    Strategies for demand management in Ontario were examined via 2 scenarios for a commercial/institutional building with a normal summertime peak load of 300 kW between 14:00 and 18:00 during a period of high electricity demand and high electricity prices. The first scenario involved the deployment of a 150 kW on-site generator fuelled by either diesel or natural gas. The second scenario involved curtailing load by 60 kW during the same periods. Costs and benefits of both scenarios were evaluated for 3 groups: consumers, system operators and society. Benefits included electricity cost savings, deferred transmission capacity development, lower system prices for electricity, as well as environmental changes, economic development, and a greater sense of corporate social responsibility. It was noted that while significant benefits were observed for all 3 groups, they were not substantial enough to encourage action, as the savings arising from deferred generation capacity development do not accrue to individual players. The largest potential benefit was identified as lower prices, spread across all users of electricity in Ontario. It was recommended that representative bodies cooperate so that the system-wide benefits can be reaped. It was noted that if 10 municipal utilities were able to have 250 commercial or institutional customers engaged in distributed response, then a total peak demand reduction of 375 MW could be achieved, representing more than 25 per cent of Ontario's target for energy conservation. It was concluded that demand response often involves the investment of capital and new on-site procedures, which may affect reactions to various incentives. 78 refs., 10 tabs., 5 figs

  6. Swedish Retrievability Scenarios

    International Nuclear Information System (INIS)

    After a brief presentation of the retrievability concept and of the plan for the construction and operation of a final repository for spent nuclear fuel (not a facility for long-term storage), the author presents different scenarios associated with the application of the retrievability concept. It is applied either before closure (three scenarios are identified: shortcomings/mistakes during deposition operations may have to be corrected by retrieving single canisters for inspection or other measures; during the operation time of the repository the acquisition of new knowledge results in the long-term safety case being questioned; during the operation time of the repository it is decided that new nuclear power should be installed in Sweden), or after closure (two scenarios are formulated: sometime after deposition of the last canister the acquisition of new knowledge results in the long-term safety case being questioned, sometime after closure of the repository, the repository is regarded as an asset containing valuable material and not 'waste')

  7. Air passivation of metal hydride beds for waste disposal

    International Nuclear Information System (INIS)

    One waste acceptance criteria for hydride bed waste disposal is that the bed be non-pyrophoric. Batch-wise air ingress tests were performed which determined the amount of air consumed by a metal hydride bed. A desorbed, 4.4 kg titanium prototype hydride storage vessel (HSV) produced a 4.4 deg.C internal temperature rise upon the first air exposure cycle and a 0.1 deg.C temperature rise upon a second air exposure. A total of 346 sec air was consumed by the bed (0.08 sec per gram Ti). A desorbed, 9.66 kg LaNi4.25Al0.75 prototype storage bed experienced larger temperature rises over successive cycles of air ingress and evacuation. The cycles were performed over a period of days with the bed effectively passivated after the 12. cycle. Nine to ten STP-L of air reacted with the bed producing both oxidized metal and water. (authors)

  8. National Coal Utilization Assessment. a preliminary assessment of the health and environmental effects of coal utilization in the Midwest. Volume I. Energy scenarios, technology characterizations, air and water resource impacts, and health effects

    Energy Technology Data Exchange (ETDEWEB)

    1977-01-01

    This report presents an initial evaluation of the major health and environmental issues associated with increased coal use in the six midwestern states of Illinois, Indiana, Michigan, Minnesota, Ohio, and Wisconsin. Using an integrated assessment approach, the evaluation proceeds from a base-line scenario of energy demand and facility siting for 1975-2020. Emphasis is placed on impacts from coal extraction, land reclamation, coal combustion for electrical generation, and coal gasification. The range of potential impacts and constraints is illustrated by a second scenario that represents an expected upper limit for coal utilization in Illinois. The following are among the more significant issues identified and evaluated in this study: If environmental and related issues can be resolved, coal will continue to be a major source of energy for the Midwest; existing sulfur emission constraints will increase use of western coal; the resource requirements and environmental impacts of coal utilization will require major significant environmental and economic tradeoffs in site selection; short-term (24-hr) ambient standards for sulfur dioxide will limit the sizes of coal facilities or require advanced control technologies; an impact on public health may result from long-range transport of airborne sulfur emissions from coal facilities in the Midwest; inadequately controlled effluents from coal gasification may cause violations of water-quality standards; the major ecological effects of coal extraction are from pre-mining and post-reclamation land use; and sulfur dioxide is the major potential contributor to effects on vegetation of atmospheric emissions from coal facilities.

  9. Scenario-Based Stochastic Programs: Strategies for Deleting Scenarios

    OpenAIRE

    Dupacova, J.

    1995-01-01

    The proposed strategies for deleting scenarios are based on postoptimality analysis of the optimal value function with respect to probabilities of the included scenarios. These strategies can be used to reduce the size of the large scenario based problems or of the problems constructed in the course of specific numerical procedures, such as stochastic decomposition or scenario aggregation. A convex nonsmooth optimization problem is replaced by a sequence of line search problems along rec...

  10. Scenarios for the future

    International Nuclear Information System (INIS)

    This project aims primarily to give a basis for the joint R and D program for the Swedish electric utility industry, in the form of pictures of the future up to 2020. The work was performed during four seminars in a group of managers and R and D planners. The four scenarios differ mainly in the assumptions of high or low economic growth and on market or political rule. Assumptions on essential uncertainties about the future have been combined in a consistent manner, e.g. on the structure of the utility industry, the role of nuclear power, the importance of the greenhouse gas issue, the influence of new technology developments and on changes of values in society. Certain other development appear in all scenarios, e.g. the impact of information technology throughout society, the internationalization of business in general and industrial production in particular, considerations for the environment and care for natural resources. The four scenarios are: 'Technology on the throne' (market rule/high growth); 'Intense competition' (market rule/low growth); 'Monopoly takes over' (political rule/high growth); and 'Green local society' (political rule/low growth). Some of the important factors pointed out by the study are: Increased customer mobility between regions and countries; The impact of information technology; Societal value changes; Sustainable development as an important driving force; Structure of the utility industry. Diversifying into new services. New players; Access to knowledge and competence; Ways for handling the greenhouse gas problem; Preparedness for nuclear power phase-out. 12 figs, 6 tabs

  11. Evolving practices in environmental scenarios: a new scenario typology

    Energy Technology Data Exchange (ETDEWEB)

    Wilkinson, Angela; Eidinow, Esther [James Martin Institute, Said Business School, University of Oxford, Park End Street, Oxford OX1 1HP (United Kingdom)

    2008-10-15

    A new approach to scenarios focused on environmental concerns, changes and challenges, i.e. so-called 'environmental scenarios', is necessary if global environmental changes are to be more effectively appreciated and addressed through sustained and collaborative action. On the basis of a comparison of previous approaches to global environmental scenarios and a review of existing scenario typologies, we propose a new scenario typology to help guide scenario-based interventions. This typology makes explicit the types of and/or the approaches to knowledge ('the epistemologies') which underpin a scenario approach. Drawing on previous environmental scenario projects, we distinguish and describe two main types in this new typology: 'problem-focused' and 'actor-centric'. This leads in turn to our suggestion for a third type, which we call 'RIMA'-'reflexive interventionist or multi-agent based'. This approach to scenarios emphasizes the importance of the involvement of different epistemologies in a scenario-based process of action learning in the public interest. We suggest that, by combining the epistemologies apparent in the previous two types, this approach can create a more effective bridge between longer-term thinking and more immediate actions. Our description is aimed at scenario practitioners in general, as well as those who work with (environmental) scenarios that address global challenges.

  12. Evolving practices in environmental scenarios: a new scenario typology

    Science.gov (United States)

    Wilkinson, Angela; Eidinow, Esther

    2008-10-01

    A new approach to scenarios focused on environmental concerns, changes and challenges, i.e. so-called 'environmental scenarios', is necessary if global environmental changes are to be more effectively appreciated and addressed through sustained and collaborative action. On the basis of a comparison of previous approaches to global environmental scenarios and a review of existing scenario typologies, we propose a new scenario typology to help guide scenario-based interventions. This typology makes explicit the types of and/or the approaches to knowledge ('the epistemologies') which underpin a scenario approach. Drawing on previous environmental scenario projects, we distinguish and describe two main types in this new typology: 'problem-focused' and 'actor-centric'. This leads in turn to our suggestion for a third type, which we call 'RIMA'—'reflexive interventionist or multi-agent based'. This approach to scenarios emphasizes the importance of the involvement of different epistemologies in a scenario-based process of action learning in the public interest. We suggest that, by combining the epistemologies apparent in the previous two types, this approach can create a more effective bridge between longer-term thinking and more immediate actions. Our description is aimed at scenario practitioners in general, as well as those who work with (environmental) scenarios that address global challenges.

  13. Evolving practices in environmental scenarios: a new scenario typology

    International Nuclear Information System (INIS)

    A new approach to scenarios focused on environmental concerns, changes and challenges, i.e. so-called 'environmental scenarios', is necessary if global environmental changes are to be more effectively appreciated and addressed through sustained and collaborative action. On the basis of a comparison of previous approaches to global environmental scenarios and a review of existing scenario typologies, we propose a new scenario typology to help guide scenario-based interventions. This typology makes explicit the types of and/or the approaches to knowledge ('the epistemologies') which underpin a scenario approach. Drawing on previous environmental scenario projects, we distinguish and describe two main types in this new typology: 'problem-focused' and 'actor-centric'. This leads in turn to our suggestion for a third type, which we call 'RIMA'-'reflexive interventionist or multi-agent based'. This approach to scenarios emphasizes the importance of the involvement of different epistemologies in a scenario-based process of action learning in the public interest. We suggest that, by combining the epistemologies apparent in the previous two types, this approach can create a more effective bridge between longer-term thinking and more immediate actions. Our description is aimed at scenario practitioners in general, as well as those who work with (environmental) scenarios that address global challenges.

  14. OECD MCCI Small-Scale Water Ingression and Crust Strength tests (SSWICS) design report, Rev. 2 October 31, 2002.

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, M.; Lomperski, S.; Kilsdonk, D.; Aeschlimann, B.; Pfeiffer, P. (Nuclear Engineering Division); (NRC)

    2011-05-23

    The Melt Attack and Coolability Experiments (MACE) program at Argonne National Laboratory addressed the issue of the ability of water to cool and thermally stabilize a molten core/concrete interaction (MCCI) when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the melt to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to melt quenching. However, due to the integral nature of these tests, several questions regarding the crust freezing behavior could not be adequately resolved. These questions include: (1) To what extent does water ingression into the crust increase the melt quench rate above the conduction-limited rate and how is this affected by melt composition and system pressure and (2) What is the fracture strength of the corium crust when subjected to a thermal-mechanical load and how does it depend upon the melt composition? A series of separate-effects experiments are planned to address these issues. The first employs an apparatus designed to measure the quench rate of a pool of corium ({approx}{phi}30 cm; up to 20 cm deep). The main parameter to be varied in these quench tests is the melt composition since it is thought to have a critical influence on the crust cracking behavior which, in turn, alters quench rate. A description of the test apparatus, instrumentation, data reduction, and test matrix are the subject of the first portion of this report. The issue of crust strength will be addressed with a second apparatus designed to mechanically load the crust produced by the quench tests. This apparatus will measure the fracture strength of the crust while under a thermal load created by a heating element beneath the crust. The introduction of a thermal gradient across the crust is thought to be important for these tests because of uncertainty in the magnitude of the thermal stresses and thus their

  15. Scenarios for fusion energy

    International Nuclear Information System (INIS)

    Are there scenarios for the near future (5-10 years) in which the public interest in, and political support for, fusion energy are likely to increase significantly? If such a scenario should occur, what should the status of heavy-ion fusion be at that time so that it is looked upon as a favored approach? If such a status can be identified, what should the research strategy be so that this status can be achieved in a timely way? This paper will look for answers to the first two of the above questions. If the goal of a desired status can be identified, the research strategy may become obvious. Of the four long-term energy options - coal, solar, fission breeders and fusion - the present position of fusion is in fourth place, never having generated any power. However, coal has environmental and safety problems. Solar has limitations of cost, availability and space requirements. Fission in general, and breeder reactors in particular, have problems of cost, environment and public acceptance. To be accepted and elevated to a position of equality with the others, heavy-ion fusion must simultaneously avoid their real and perceived major flaws. To succeed, heavy-ion fusion must strive to be markedly the best fusion option. (orig.)

  16. ILC Operating Scenarios

    International Nuclear Information System (INIS)

    The ILC Technical Design Report documents the design for the construction of a linear collider which can be operated at energies up to 500 GeV. This report summarizes the outcome of a study of possible running scenarios, including a realistic estimate of the real time accumulation of integrated luminosity based on ramp-up and upgrade processes. The evolution of the physics outcomes is emphasized, including running initially at 500 GeV, then at 350 GeV and 250 GeV. The running scenarios have been chosen to optimize the Higgs precision measurements and top physics while searching for evidence for signals beyond the standard model, including dark matter. In addition to the certain precision physics on the Higgs and top that is the main focus of this study, there are scientific motivations that indicate the possibility for discoveries of new particles in the upcoming operations of the LHC or the early operation of the ILC. Follow-up studies of such discoveries could alter the plan for the centre-of-mass collision energy of the ILC and expand the scientific impact of the ILC physics program. It is envisioned that a decision on a possible energy upgrade would be taken near the end of the twenty year period considered in this report.

  17. EXAMPLE EXPOSURE SCENARIOS ASSESSMENT TOOL

    Science.gov (United States)

    Exposure scenarios are a tool to help the assessor develop estimates of exposure, dose, and risk. An exposure scenario generally includes facts, data, assumptions, inferences, and sometimes professional judgment about how the exposure takes place. The human physiological and beh...

  18. Quantifying four scenarios for Europe

    OpenAIRE

    Arjan Lejour

    2003-01-01

    This study presents four economic scenarios for Europe until 2040. The scenarios are developed around two key uncertainties: international cooperation and institutional reforms. In the scenarios Strong Europe (SE) and Global Economy (GE), international cooperation is prominent, while the other scenarios, Regional Communities (RC) and Transatlantic Market (TM), feature limited international cooperation. Public institutions are important in Strong Europe and Regional Communities. In Global Econ...

  19. 40 Years of Shell Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-02-15

    Shell has been using scenario planning for four decades. During that time these scenarios have helped the company and governments across the world to make better strategic choices. Scenarios provide lenses that help see future prospects more clearly, make richer judgments and be more sensitive to uncertainties. Discover how the Shell Scenarios team has helped guide decision makers at major moments in history and get a peek at the team future focus, including the intricate relationship between energy, water and food.

  20. Strategic Scenario Construction Made Easy

    DEFF Research Database (Denmark)

    Duus, Henrik Johannsen

    2016-01-01

    article uses insights from the area of strategic forecasting (of which scenario planning is a proper subset) and experiences gained from a recent course in that area to develop a simpler, more direct, hands-on method for scenario construction and to provide several ideas for scenario construction that can...

  1. Biomass Scenario Model Scenario Library: Definitions, Construction, and Description

    Energy Technology Data Exchange (ETDEWEB)

    Inman, D.; Vimmerstedt, L.; Bush, B.; Peterson, S.

    2014-04-01

    Understanding the development of the biofuels industry in the United States is important to policymakers and industry. The Biomass Scenario Model (BSM) is a system dynamics model of the biomass-to-biofuels system that can be used to explore policy effects on biofuels development. Because of the complexity of the model, as well as the wide range of possible future conditions that affect biofuels industry development, we have not developed a single reference case but instead developed a set of specific scenarios that provide various contexts for our analyses. The purpose of this report is to describe the scenarios that comprise the BSM scenario library. At present, we have the following policy-focused scenarios in our library: minimal policies, ethanol-focused policies, equal access to policies, output-focused policies, technological diversity focused, and the point-of-production- focused. This report describes each scenario, its policy settings, and general insights gained through use of the scenarios in analytic studies.

  2. Effects of Implant Design Parameters on Fluid Convection, Potentiating 3rd Body Debris Ingress into the Bearing Surface during THA Impingement/Subluxation

    OpenAIRE

    Lundberg, Hannah J.; Pedersen, Douglas R.; Baer, Thomas E.; Muste, Marian; Callaghan, John J.; Brown, Thomas D.

    2007-01-01

    Aseptic loosening from polyethylene wear debris is the leading cause of failure for metal-on-polyethylene total hip implants. Third body debris ingress to the bearing space results in femoral head roughening and acceleration of polyethylene wear. How third body particles manage to enter the bearing space between the closely conforming articulating surfaces of the joint is not well understood. We hypothesize that one such mechanism is from convective fluid transport during subluxation of the t...

  3. Fick's 2nd law - Complete solutions for chloride ingress into concrete – with focus on time dependent diffusivity and boundary condition

    OpenAIRE

    Frederiksen, Jens M.; Mejlbro, Leif; Nilsson, Lars-Olof

    2009-01-01

    This report focuses on models of chloride ingress into concrete that are based on mathematical solutions of Fick's second law. In recent years a lot of confusion has been identified concerning these models. In some cases time-dependencies of diffusivity have been used in a mathematically incorrect way. In other cases field and laboratory data from one way of describing the time-dependency of these diffusivities has been used in models that are based on another model. This is now clarified...

  4. An Accelerated Test Method of Simultaneous Carbonation and Chloride Ion Ingress: Durability of Silica Fume Concrete in Severe Environments

    Directory of Open Access Journals (Sweden)

    S. A. Ghahari

    2016-01-01

    Full Text Available The effects of simultaneous carbonation and chloride ion attack on mechanical characteristics and durability of concrete containing silica fume have been investigated through an accelerated test method. Specimens containing different amounts of silica fume were maintained in an apparatus in which carbon dioxide pressure and concentration and relative humidity were kept constant, and wetting and drying cycles in saline water were applied. Surface resistivity, sorptivity, CO2 consumption, and carbonation and chloride ion ingress depths measurements were taken. Phase change due to carbonation and chloride ion attack was monitored by XRD analysis, and microstructures and interfacial transition zones were studied by implementing SEM as well as mercury intrusion porosimetry. It was expected to have a synergistic effect in the tidal zone where simultaneous carbonation and chloride ion attack happen. However, the observed reduced surface resistivity, compared to specimens maintained in CO2 gas, could be due to the moisture that is available near the surface, hindering CO2 from penetrating into the pores of the specimens. Moreover, the porosity analysis of the specimens showed that the sample containing silica fume cured in the tidal zone had 50.1% less total porosity than the plain cement paste cured in the same condition.

  5. Scenario development methodologies

    International Nuclear Information System (INIS)

    In the period 1981-1994, SKB has studied several methodologies to systematize and visualize all the features, events and processes (FEPs) that can influence a repository for radioactive waste in the future. All the work performed is based on the terminology and basic findings in the joint SKI/SKB work on scenario development presented in the SKB Technical Report 89-35. The methodologies studied are a) Event tree analysis, b) Influence diagrams and c) Rock Engineering Systems (RES) matrices. Each one of the methodologies is explained in this report as well as examples of applications. One chapter is devoted to a comparison between the two most promising methodologies, namely: Influence diagrams and the RES methodology. In conclusion a combination of parts of the Influence diagram and the RES methodology is likely to be a promising approach. 26 refs

  6. Scenario planning and nanotechnological futures

    International Nuclear Information System (INIS)

    Scenario planning may assist us in harnessing the benefits of nanotechnology and managing the associated risks for the good of the society. Scenario planning is a way to describe the present state of the world and develop several hypotheses about the future of the world, thereby enabling discussions about how the world ought to be. Scenario planning thus is not only a tool for learning and foresight, but also for leadership. Informed decision making by experts and political leaders becomes possible, while simultaneously allaying the public's perception of the risks of new and emerging technologies such as nanotechnology. Two scenarios of the societal impact of nanotechnology are the mixed-signals scenario and the confluence scenario. Technoscientists have major roles to play in both scenarios.

  7. Scenario planning and nanotechnological futures

    Science.gov (United States)

    Farber, Darryl; Lakhtakia, Akhlesh

    2009-07-01

    Scenario planning may assist us in harnessing the benefits of nanotechnology and managing the associated risks for the good of the society. Scenario planning is a way to describe the present state of the world and develop several hypotheses about the future of the world, thereby enabling discussions about how the world ought to be. Scenario planning thus is not only a tool for learning and foresight, but also for leadership. Informed decision making by experts and political leaders becomes possible, while simultaneously allaying the public's perception of the risks of new and emerging technologies such as nanotechnology. Two scenarios of the societal impact of nanotechnology are the mixed-signals scenario and the confluence scenario. Technoscientists have major roles to play in both scenarios.

  8. Waste package scenario modelling

    International Nuclear Information System (INIS)

    UK Nirex has supported a programme of work to develop models describing the post-closure evolution of intermediate-level waste packages with the objectives of: - providing support and justification for the parameters and representations used in performance assessment models; - informing future model development and packaging advice. Scenarios for the potential evolution of a waste package were developed and modelled taking explicit account of waste package heterogeneity and the time-dependence of the physical and chemical characteristics of the system. The modelling work highlighted the treatment of organic complexants and the representation of physical containment as two areas in which the impacts of time dependence and package scale heterogeneity might be particularly significant. A subsequent study of the impact of organic complexants emphasised the importance of heterogeneity in package inventory in determining the radionuclide release from the near field. The degree of containment afforded by the wasteform and the waste container has been investigated as part of a study to develop a preliminary understanding of the mixing scales within the repository. The study suggests that the most important control on the release of radionuclides from the waste packages is the integrity of the waste encapsulation grout. Interactions between neighbouring packages are to be expected, but the degree to which homogeneous (well mixed) conditions develop may be limited in both time and space. (author)

  9. Isotopic measurements in research on seawater ingression in the carbonate aquifer of the Salentine Peninsula, Southern Italy

    International Nuclear Information System (INIS)

    Cretaceous calcareous and dolomitic rocks, bedded, jointed and karstified, and hence generally very permeable, form the basement of the Salentine Peninsula. These rocks constitute a huge aquifer with fresh and brackish groundwaters that float on groundwaters of marine origin. Sea level constitutes the base level of the ground waters. A basic outline is first given of the hydrogeology and the paleohydrogeology, so as to provide the necessary background information on the seawater intrusion phenomenon and to permit comparison of the results of the isotope data with those obtained by the classical methods of hydrogeological investigation. This is followed by presentation of the results of the isotopic measurements on 18O, D, 13C and 14C. The δ13C contents indicate, in good agreement with the carbon dioxide and bicarbonate concentrations, that seawater ingression leads to the migration of carbon dioxide from the fresh and brackish waters towards the subjacent intrusive waters of marine origin. Along those stretches of coast where the seawaters are in direct communication with the groundwaters, all the isotope data point to very active renewal of groundwaters of marine origin by seawater. In the central parts of the peninsula and along those stretches of coast where direct communication between seawaters and groundwaters is impeded by impervious clays, the 14C contents indicate that the seawater intrusion and consequently the migration of carbon dioxide are either very slow and continuous in time or that they occurred relatively rapidly in the past. Taking into consideration the paleohydrogeology of the peninsula, and the fact that the δ18O and δD values are higher than those of the present seawaters, leads to the belief that seawater intrusion may well have occurred during major variations in the sea level in the past, when climatic conditions were different from those now prevailing. (author)

  10. Learning from global emissions scenarios

    International Nuclear Information System (INIS)

    Scenarios of global greenhouse gas emissions have played a key role in climate change analysis for over twenty years. Currently, several research communities are organizing to undertake a new round of scenario development in the lead-up to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). To help inform this process, we assess a number of past efforts to develop and learn from sets of global greenhouse gas emissions scenarios. We conclude that while emissions scenario exercises have likely had substantial benefits for participating modeling teams and produced insights from individual models, learning from the exercises taken as a whole has been more limited. Model comparison exercises have typically focused on the production of large numbers of scenarios while investing little in assessing the results or the production process, perhaps on the assumption that later assessment efforts could play this role. However, much of this assessment potential remains untapped. Efforts such as scenario-related chapters of IPCC reports have been most informative when they have gone to extra lengths to carry out more specific comparison exercises, but in general these assessments do not have the remit or resources to carry out the kind of detailed analysis of scenario results necessary for drawing the most useful conclusions. We recommend that scenario comparison exercises build-in time and resources for assessing scenario results in more detail at the time when they are produced, that these exercises focus on more specific questions to improve the prospects for learning, and that additional scenario assessments are carried out separately from production exercises. We also discuss the obstacles to better assessment that might exist, and how they might be overcome. Finally, we recommend that future work include much greater emphasis on understanding how scenarios are actually used, as a guide to improving scenario production.

  11. NATIONAL COMPETITIVENESS - SCENARIOS FOR ROMANIA

    OpenAIRE

    Herciu, Mihaela

    2012-01-01

    Competitiveness remains a continuous concern of nations in any stage of development, from factor based economy to innovation based economy. The present paper aims to emphasize the current level of national competitiveness of Romania, on one hand, and to identify possible ways to improve the current level by building scenarios in order to eliminate the uncertainty, on the other hand. The paper proposes four scenarios for increase GCI (growth competitiveness index) and four scenarios from pessi...

  12. Scenario Planning and Nanotechnological Futures

    OpenAIRE

    Farber, Darryl; Lakhtakia, Akhlesh

    2008-01-01

    Scenario planning may assist us in harnessing the benefits of nanotechnology and managing the associated risks for the good of the society. Scenario planning is a way to describe the present state of the world and develop several hypotheses about the future of the world, thereby enabling discussions about how the world ought to be. Scenario planning thus is not only a tool for learning and foresight, but also for leadership. Informed decision-making by experts and political leaders becomes po...

  13. Air Quality and Climate Change

    International Nuclear Information System (INIS)

    Climate change and air quality are closely related: through the policy measures implemented to mitigate these major environmental threats but also through the geophysical processes that drive them. We designed, developed and implemented a comprehensive regional air quality and climate modeling System to investigate future air quality in Europe taking into account the combined pressure of future climate change and long range transport. Using the prospective scenarios of the last generation of pathways for both climate change (emissions of well mixed greenhouse gases) and air pollutants, we can provide a quantitative view into the possible future air quality in Europe. We find that ozone pollution will decrease substantially under the most stringent scenario but the efforts of the air quality legislation will be adversely compensated by the penalty of global warming and long range transport for the business as usual scenario. For particulate matter, the projected reduction of emissions efficiently reduces exposure levels. (authors)

  14. The changing nutrition scenario

    Directory of Open Access Journals (Sweden)

    C Gopalan

    2013-01-01

    Full Text Available The past seven decades have seen remarkable shifts in the nutritional scenario in India. Even up to the 1950s severe forms of malnutrition such as kwashiorkar and pellagra were endemic. As nutritionists were finding home-grown and common-sense solutions for these widespread problems, the population was burgeoning and food was scarce. The threat of widespread household food insecurity and chronic undernutrition was very real. Then came the Green Revolution. Shortages of food grains disappeared within less than a decade and India became self-sufficient in food grain production. But more insidious problems arising from this revolution were looming, and cropping patterns giving low priority to coarse grains and pulses, and monocropping led to depletion of soil nutrients and ′Green Revolution fatigue′. With improved household food security and better access to health care, clinical manifestations of severe malnutrition virtually disappeared. But the decline in chronic undernutrition and "hidden hunger" from micronutrient deficiencies was slow. On the cusp of the new century, an added factor appeared on the nutritional scene in India. With steady urban migration, upward mobility out of poverty, and an increasingly sedentary lifestyle because of improvements in technology and transport, obesity rates began to increase, resulting in a dual burden. Measured in terms of its performance in meeting its Millennium Development Goals, India has fallen short. Despite its continuing high levels of poverty and illiteracy, India has a huge demographic potential in the form of a young population. This advantage must be leveraged by investing in nutrition education, household access to nutritious diets, sanitary environment and a health-promoting lifestyle. This requires co-operation from all the stakeholders, including governments, non government organizations, scientists and the people at large.

  15. The changing nutrition scenario.

    Science.gov (United States)

    Gopalan, C

    2013-09-01

    The past seven decades have seen remarkable shifts in the nutritional scenario in India. Even up to the 1950s severe forms of malnutrition such as kwashiorkar and pellagra were endemic. As nutritionists were finding home-grown and common-sense solutions for these widespread problems, the population was burgeoning and food was scarce. The threat of widespread household food insecurity and chronic undernutrition was very real. Then came the Green Revolution. Shortages of food grains disappeared within less than a decade and India became self-sufficient in food grain production. But more insidious problems arising from this revolution were looming, and cropping patterns giving low priority to coarse grains and pulses, and monocropping led to depletion of soil nutrients and 'Green Revolution fatigue'. With improved household food security and better access to health care, clinical manifestations of severe malnutrition virtually disappeared. But the decline in chronic undernutrition and "hidden hunger" from micronutrient deficiencies was slow. On the cusp of the new century, an added factor appeared on the nutritional scene in India. With steady urban migration, upward mobility out of poverty, and an increasingly sedentary lifestyle because of improvements in technology and transport, obesity rates began to increase, resulting in a dual burden. Measured in terms of its performance in meeting its Millennium Development Goals, India has fallen short. Despite its continuing high levels of poverty and illiteracy, India has a huge demographic potential in the form of a young population. This advantage must be leveraged by investing in nutrition education, household access to nutritious diets, sanitary environment and a health-promoting lifestyle. This requires co-operation from all the stakeholders, including governments, non government organizations, scientists and the people at large. PMID:24135189

  16. Modelling of cladding oxidation by air under severe accident conditions with the MAAP 4 code

    International Nuclear Information System (INIS)

    In a nuclear power plant, air ingress into the vessel is a potential risk in some low probable situations of severe accidents. Air is a highly oxidizing atmosphere that can lead to an enhanced core oxidation and degradation affecting the release of FP. This is particularly true speaking about ruthenium release, which can be significantly increased in the presence of air. This is a key issue due to the high radio-toxicity of ruthenium and its ability to form highly volatile oxides. The oxygen affinity is decreasing in priority from the Zircaloy cladding, to fuel and ruthenium inclusions. It is consequently of great need to understand the phenomena governing cladding oxidation by air as a prerequisite for the source term issues in such scenarios. As a first step, a phenomenological study has been carried out to characterize nitriding of the Zircaloy claddings. In summary, nitriding occurs preferentially when the oxygen has been consumed locally or in case of total oxygen starvation and when the cladding was slightly pre-oxidized. Just like oxidation, nitriding can be modeled in a simplified form as a cladding weight gain in terms of thickness. The model implemented in MAAP takes this into account as well as re-oxidation of the nitrides, in the case where oxygen is available again (especially during a reflood). Several correlations were thus integrated and a new one, called “KIT-EDF”, was developed, based on KIT separate-effect tests. The model has been implemented and validated against QUENCH-16 and QUENCH-10 experiments, studying the oxidation in air atmosphere of an assembly pre-oxidized in steam and finally quenched with water. The simulations give encouraging results since the modeling of nitriding effects has increased hydrogen production during reflood, as experimentally observed. The results of this study lead us to identify a number of perspectives for the future, namely taking into account the changes in the structure of the oxide layer during a

  17. Automated Analysis of Infinite Scenarios

    DEFF Research Database (Denmark)

    Buchholtz, Mikael

    The security of a network protocol crucially relies on the scenario in which the protocol is deployed. This paper describes syntactic constructs for modelling network scenarios and presents an automated analysis tool, which can guarantee that security properties hold in all of the (infinitely many...

  18. Engaging Personas and Narrative Scenarios

    DEFF Research Database (Denmark)

    Nielsen, Lene

    2004-01-01

    design ideas. The concept of engaging personas and narrative scenario explores personas in the light of what what it is to identify with and have empathy with a character. The concept of narrative scenarios views the narrative as aid for exploration of design ideas. Both concepts incorporate a...

  19. Energy scenarios: a prospective outlook

    International Nuclear Information System (INIS)

    A set of articles discusses the use of energy scenarios: how useful they can be to describe a possible future and even to gather the involved actors, how they have been used in France in the past (for planning or prediction purposes, with sometimes some over-assessed or contradictory results, without considering any decline of nuclear energy, or by setting an impossible equation in the case of the Grenelle de l'Environnement), how the scenario framework impacts its content (depending on the approach type: standard, optimization, bottom-up, top-down, or hybrid). It also discusses the issue of choice of hypotheses on growth-based and de-growth-based scenarios, outlines how energy saving is a key for a sustainable evolution. Two German scenarios regarding electricity production (centralisation or decentralisation) and French regional scenarios for Nord-Pas-de-Calais are then briefly discussed

  20. Underground infrastructure damage for a Chicago scenario

    Energy Technology Data Exchange (ETDEWEB)

    Dey, Thomas N [Los Alamos National Laboratory; Bos, Rabdall J [Los Alamos National Laboratory

    2011-01-25

    Estimating effects due to an urban IND (improvised nuclear device) on underground structures and underground utilities is a challenging task. Nuclear effects tests performed at the Nevada Test Site (NTS) during the era of nuclear weapons testing provides much information on how underground military structures respond. Transferring this knowledge to answer questions about the urban civilian environment is needed to help plan responses to IND scenarios. Explosions just above the ground surface can only couple a small fraction of the blast energy into an underground shock. The various forms of nuclear radiation have limited penetration into the ground. While the shock transmitted into the ground carries only a small fraction of the blast energy, peak stresses are generally higher and peak ground displacement is lower than in the air blast. While underground military structures are often designed to resist stresses substantially higher than due to the overlying rocks and soils (overburden), civilian structures such as subways and tunnels would generally only need to resist overburden conditions with a suitable safety factor. Just as we expect the buildings themselves to channel and shield air blast above ground, basements and other underground openings as well as changes of geology will channel and shield the underground shock wave. While a weaker shock is expected in an urban environment, small displacements on very close-by faults, and more likely, soils being displaced past building foundations where utility lines enter could readily damaged or disable these services. Immediately near an explosion, the blast can 'liquefy' a saturated soil creating a quicksand-like condition for a period of time. We extrapolate the nuclear effects experience to a Chicago-based scenario. We consider the TARP (Tunnel and Reservoir Project) and subway system and the underground lifeline (electric, gas, water, etc) system and provide guidance for planning this scenario.

  1. Chloride ingress prediction

    DEFF Research Database (Denmark)

    Frederiksen, Jens Mejer; Geiker, Mette Rica

    2008-01-01

    makes physical sense for the design engineer, i.e. the achieved chloride diffusion coefficients at 1 year and 100 years, D1 and D100 respectively, and the corresponding achieved chloride concentrations at the exposed concrete surface, C1 and C100. Data from field exposure supports the assumption of time...... dependent surface chloride concentrations and the diffusion coefficients. Model parameters for Portland cement concretes with and without silica fume and fly ash in marine atmospheric and submerged South Scandinavian environment are suggested in a companion paper based on 10 years field exposure data....

  2. 40 CFR 68.28 - Alternative release scenario analysis.

    Science.gov (United States)

    2010-07-01

    .... 68.28 Section 68.28 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... alternative release scenarios: (1) The five-year accident history provided in § 68.42; and (2) Failure... applicable as part of current practices. Proprietary models that account for the modeling conditions may...

  3. Arctic shipping emissions inventories and future scenarios

    Directory of Open Access Journals (Sweden)

    J. J. Corbett

    2010-04-01

    Full Text Available The Arctic is a sensitive region in terms of climate change and a rich natural resource for global economic activity. Arctic shipping is an important contributor to the region's anthropogenic air emissions, including black carbon – a short-lived climate forcing pollutant especially effective in accelerating the melting of ice and snow. These emissions are projected to increase as declining sea ice coverage due to climate change allows for increased shipping activity in the Arctic. To understand the impacts of these increased emissions, scientists and modelers require high-resolution, geospatial emissions inventories that can be used for regional assessment modeling. This paper presents 5 km×5 km Arctic emissions inventories of important greenhouse gases, black carbon and other pollutants under existing and future (2050 scenarios that account for growth of shipping in the region, potential diversion traffic through emerging routes, and possible emissions control measures. Short-lived forcing of ~4.5 gigagrams of black carbon from Arctic shipping may increase climate forcing; a first-order calculation of global warming potential due to 2030 emissions in the high-growth scenario suggests that short-lived forcing of ~4.5 gigagrams of black carbon from Arctic shipping may increase climate forcing due to Arctic ships by at least 17% compared to warming from these vessels' CO2 emissions (~42 000 gigagrams. The paper also presents maximum feasible reduction scenarios for black carbon in particular. These emissions reduction scenarios will enable scientists and policymakers to evaluate the efficacy and benefits of technological controls for black carbon, and other pollutants from ships.

  4. Probabilistic Climate Scenario Information for Risk Assessment

    Science.gov (United States)

    Dairaku, K.; Ueno, G.; Takayabu, I.

    2014-12-01

    Climate information and services for Impacts, Adaptation and Vulnerability (IAV) Assessments are of great concern. In order to develop probabilistic regional climate information that represents the uncertainty in climate scenario experiments in Japan, we compared the physics ensemble experiments using the 60km global atmospheric model of the Meteorological Research Institute (MRI-AGCM) with multi-model ensemble experiments with global atmospheric-ocean coupled models (CMIP3) of SRES A1b scenario experiments. The MRI-AGCM shows relatively good skills particularly in tropics for temperature and geopotential height. Variability in surface air temperature of physical ensemble experiments with MRI-AGCM was within the range of one standard deviation of the CMIP3 model in the Asia region. On the other hand, the variability of precipitation was relatively well represented compared with the variation of the CMIP3 models. Models which show the similar reproducibility in the present climate shows different future climate change. We couldn't find clear relationships between present climate and future climate change in temperature and precipitation. We develop a new method to produce probabilistic information of climate change scenarios by weighting model ensemble experiments based on a regression model (Krishnamurti et al., Science, 1999). The method can be easily applicable to other regions and other physical quantities, and also to downscale to finer-scale dependent on availability of observation dataset. The prototype of probabilistic information in Japan represents the quantified structural uncertainties of multi-model ensemble experiments of climate change scenarios. Acknowledgments: This study was supported by the SOUSEI Program, funded by Ministry of Education, Culture, Sports, Science and Technology, Government of Japan.

  5. Numerical simulation of the facility behaviour of a high temperature reactor under water ingress accidents at the example of the AVR

    International Nuclear Information System (INIS)

    Detailed analysis of massive water ingress accidents in high temperature reactors supposes a numerical simulation of the whole facility behaviour. For the AVR-reactor such a model was developed to describe both, the graphite corrosion processes and the accident transients for different releasing events as well as resulting accident profiles. The variable consideration of regulating facilities of the safety circuit being influenced in reality, enables an optimization of the accident profiles in the way of a least possible facility damage. It results that in spite of extremely conservative input data with authorization legal relevance even the possible water ingress accidents can safely be controlled after 15 years of operation with steadily increasing safety requirements. First investigations on a selected facility concept for the AVR-reequipment show, that with the definition up to now of the AVR-steam generator failure the accident profiles ''reactor under pressure'' are conservatively coped with. An increasing degree of detail of the concept proposals, however, requires an examination of this statement. (orig.)

  6. Studies for scenario modelling of conditions in the nearfield of a heat-affected repository compartment in salt rock

    International Nuclear Information System (INIS)

    It is supposed that in the nearfield of heat-generating wastes a number of thermally induced processes will occur that will have significant effects on the existing brine systems. Analyses considering ingress of brines into the nearfield of a heat-generating waste form cover inter alia such conditions as brine inflow into a not fully converged mine drift, brine penetrating the backfilling material, dissolution and re-dissolution processes in the system brine/backfilling material under the influence of the temperature field, and compacting of the backfilling material due to water evaporation from the brine and crystallisation of the salt content. The scenarios developed are taken as a basis for improving the precision of models describing the nearfield processes. (DG)

  7. Forest fires and air quality under a climate change scenario

    OpenAIRE

    Carvalho, Anabela Victorino

    2008-01-01

    Os incêndios florestais e a qualidade do ar em cenário de alteração climática constituem uma das maiores ameaças ao desenvolvimento sustentável. Nestes sentido, este trabalho pretende avaliar o impacte das alterações climáticas nos incêndios florestais e na qualidade do ar. A análise estatística de doze distritos Portugueses revelou que a meteorologia e as componentes do índice Canadiano de risco de incêndio são as variáveis que determinam os números dos incêndios florestais...

  8. New reactors concepts and scenarios

    International Nuclear Information System (INIS)

    In recent years an increasing interest is observed with respect to subcritical, accelerator driven systems (ADS), for their possible role in perspective future nuclear energy scenarios, as actinide (Pu and MA) incinerators, and/or claimed energy plants with potential enhanced safety characteristics. Important research programs are devoted to the various related fields of research. Extensive studies on the ADS behavior under incidental conditions are in particular made, for verifying their claimed advantage, under the safety point of view, with respect to the corresponding critical reactors. Corresponding medium and long range scenarios are being studied to cope with a number of concerns associated with the safety (power excursions. residual heat risk), as well as with the fuel flow (criticality accidents, fuel diversion, radiological risk, proliferation). In the present work we shall try to review current lines of research in this field, and comment on possible scenarios so far envisaged. (author)

  9. Building Scenarios for Greener Gas

    International Nuclear Information System (INIS)

    In the Netherlands, the Greening of Gas project has been started to investigate the feasibility, from ecological, economic and technological perspectives, of adding hydrogen to the Dutch natural gas network. The preliminary findings of the project suggest that steam methane reforming of natural gas provides the most logical choice for the initial stages of a transition to a hydrogen economy. This presents an opportunity for research into synergistic options for hydrogen and natural gas in a combined energy supply. The approach adopted for exploring the feasibility of this idea of synergy is through the creation of plausible, internally consistent scenarios. In this paper we describe the way that the scenarios were designed and how they provide a framework for designing effective policies. These robust scenarios are a critical first-step for the development of an adaptive policy and a flexible investment strategy aimed at effecting the transition to a sustainable hydrogen economy. (authors)

  10. Oxygen Selective Membranes for Li-Air (O2 Batteries

    Directory of Open Access Journals (Sweden)

    Mark Salomon

    2012-05-01

    Full Text Available Lithium-air (Li-air batteries have a much higher theoretical energy density than conventional lithium batteries and other metal air batteries, so they are being developed for applications that require long life. Water vapor from air must be prevented from corroding the lithium (Li metal negative electrode during discharge under ambient conditions, i.e., in humid air. One method of protecting the Li metal from corrosion is to use an oxygen selective membrane (OSM that allows oxygen into the cell while stopping or slowing the ingress of water vapor. The desired properties and some potential materials for OSMs for Li-air batteries are discussed and the literature is reviewed.

  11. Scenario Analysis of the Philippine Energy Market

    OpenAIRE

    Fe Amor Parel Gudmundsson 1975

    2014-01-01

    This research project investigates the Philippine energy market. The main objective is to provide alternative scenarios, based on the propositions which are generated from literature review. Scenario Analysis is used as the primary tool for the analysis using the Delphi method which includes eight panel of experts as participants. Findings of this research concludes three scenarios: Policy Scenario, Sustainability Scenario, and Energy Price Scenario. Political will is important to address th...

  12. Scenarios of future energy intensities

    International Nuclear Information System (INIS)

    In this chapter, the authors present scenarios of potential change in energy intensities in the OECD countries and in the Soviet Union. These scenarios are meant to illustrate how intensities might evolve over the next 20 years given different conditions with respect to energy prices, energy-efficiency policies, and other key factors. Changes in intensity will also be affected by the rates of growth and stock turnover in each sector. They have not tried to forecast how activity levels and structure will evolve. However, the OECD scenarios assume a world in which GDP averages growth in the 2-3%/year range, with some differences among countries. For the Soviet Union, the degree and pace of intensity decline will be highly dependent on the success of the transition to a market economy; each scenario explicitly envisions a different degree of success. They have not constructed comparable scenarios for the developing countries. The scenarios presented in this chapter do not predict what will happen in the future. They believe, however, that they illustrate a plausible set of outcomes if energy prices, policies, programs, and other factors evolve as described in each case. With higher energy prices and vigorous policies and programs, intensities in the OECD countries in 2010 could be nearly 50% less on average than the level where trends seem to be point. In the former Soviet Union, a combination of rapid, successful economic reform and extra effort to improve energy efficiency might result in average intensity being nearly 40% less than in a slow reform case. And in the LDCs, a mixture of sound policies, programs, and energy pricing reform could also lead to intensities being far lower than they would be otherwise. 8 refs., 10 figs., 1 tab

  13. Future scenarios to inspire innovation

    DEFF Research Database (Denmark)

    De Smedt, Peter; Borch, Kristian; Fuller, Ted

    2013-01-01

    . Due to the social dynamics of innovation, new socio-technical subsystems are emerging, however there is lack of exploitation of novel ideas and sustainable solutions to address these grand challenges. In this paper we argue that issues of how knowledge is represented can have a part in this lack of...... grand challenges. By analyzing several scenario cases, elements of good practices and principles on how to strengthen innovation systems through future scenarios are identified. This is needed because innovation itself needs to be oriented along more sustainable pathways enabling transformations of...

  14. OECM MCCI Small-Scale Water Ingression and Crust Strength Tests (SSWICS) SSWICS-2 final data report, Rev. 0 February 12, 2003.

    Energy Technology Data Exchange (ETDEWEB)

    Lomperski, S.; Farmer, M. T.; Kilsdonk, D.; Aeschlimann, B. (Nuclear Engineering Division)

    2011-05-23

    The Melt Attack and Coolability Experiments (MACE) program at Argonne National Laboratory addressed the issue of the ability of water to cool and thermally stabilize a molten core/concrete interaction (MCCI) when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the melt to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to melt quenching. However, due to the integral nature of these tests, several questions regarding the crust freezing behavior could not be adequately resolved. These questions include: (1) To what extent does water ingression into the crust increase the melt quench rate above the conduction-limited rate and how is this affected by melt composition and system pressure and (2) What is the fracture strength of the corium crust when subjected to a thermal-mechanical load and how does it depend upon the melt composition? A series of separate-effects experiments are being conducted to address these issues. The first employs an apparatus designed to measure the quench rate of a pool of corium ({approx}{phi}30 cm; up to 20 cm deep). The main parameter to be varied in these quench tests is the melt composition since it is thought to have a critical influence on the crust cracking behavior which, in turn, alters quench rate. The issue of crust strength will be addressed with a second apparatus designed to mechanically load the crust produced by the quench tests. This apparatus will measure the fracture strength of the crust while under a thermal load created by a heating element beneath the crust. The two apparatuses used to measure the melt quench rate and crust strength are jointly referred to as SSWICS (Small-Scale Water Ingression and Crust Strength). This report describes results of the second water ingression test, designated SSWICS-2. The test investigated the quench behavior of a 15 cm deep

  15. OECD MMCI Small-Scale Water Ingression and Crust Strength tests (SSWICS) SSWICS-1 final data report, Rev. 1 February 10, 2003.; Report, Rev. 1

    Energy Technology Data Exchange (ETDEWEB)

    Lomperski, S.; Farmer, M. T.; Kilsdonk, D.; Aeschlimann, B. (Nuclear Engineering Division)

    2011-05-23

    The Melt Attack and Coolability Experiments (MACE) program at Argonne National Laboratory addressed the issue of the ability of water to cool and thermally stabilize a molten core/concrete interaction (MCCI) when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the melt to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to melt quenching. However, due to the integral nature of these tests, several questions regarding the crust freezing behavior could not be adequately resolved. These questions include: (1) To what extent does water ingression into the crust increase the melt quench rate above the conduction-limited rate and how is this affected by melt composition and system pressure; and (2) What is the fracture strength of the corium crust when subjected to a thermal-mechanical load and how does it depend upon the melt composition? A series of separate-effects experiments are being conducted to address these issues. The first employs an apparatus designed to measure the quench rate of a pool of corium ({approx}{phi}30 cm; up to 20 cm deep). The main parameter to be varied in these quench tests is the melt composition since it is thought to have a critical influence on the crust cracking behavior which, in turn, alters quench rate. The issue of crust strength will be addressed with a second apparatus designed to mechanically load the crust produced by the quench tests. This apparatus will measure the fracture strength of the crust while under a thermal load created by a heating element beneath the crust. The two apparatuses used to measure the melt quench rate and crust strength are jointly referred to as SSWICS (Small-Scale Water Ingression and Crust Strength). This report describes results of the first water ingression test, designated SSWICS-1. The test investigated the quench behavior of a 15 cm deep

  16. OECD MCCI Small-Scale Water Ingression and Crust Strength Tests (SSWICS) SSWICS-3 test data report : thermal Hydraulic results, Rev. 0 February 19, 2003.

    Energy Technology Data Exchange (ETDEWEB)

    Lomperski, S.; Farmer, M. T.; Kilsdonk, D.; Aeschlimann, B. (Nuclear Engineering Division)

    2011-05-23

    The Melt Attack and Coolability Experiments (MACE) program at Argonne National Laboratory addressed the issue of the ability of water to cool and thermally stabilize a molten core/concrete interaction (MCCI) when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the melt to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to melt quenching. However, due to the integral nature of these tests, several questions regarding the crust freezing behavior could not be adequately resolved. These questions include: (1) To what extent does water ingression into the crust increase the melt quench rate above the conduction-limited rate and how is this affected by melt composition and system pressure and (2) What is the fracture strength of the corium crust when subjected to a thermal-mechanical load and how does it depend upon the melt composition? A series of separate-effects experiments are being conducted to address these issues. The first employs an apparatus designed to measure the quench rate of a pool of corium ({approx}{phi}30 cm; up to 20 cm deep). The main parameter to be varied in these quench tests is the melt composition since it is thought to have a critical influence on the crust cracking behavior which, in turn, alters quench rate. The issue of crust strength will be addressed with a second apparatus designed to mechanically load the crust produced by the quench tests. This apparatus will measure the fracture strength of the crust while under a thermal load created by a heating element beneath the crust. The two apparatuses used to measure the melt quench rate and crust strength are jointly referred to as SSWICS (Small-Scale Water Ingression and Crust Strength). This report describes results of the third water ingression test, designated SSWICS-3. This test investigated the quenching behavior of a fully

  17. OECD MMCI Small-Scale Water Ingression and Crust Strength Tests (SSWICS) SSWICS-2 test data report : thermal hydraulic results, Rev. 0 September 20, 2002.

    Energy Technology Data Exchange (ETDEWEB)

    Lomperski, S.; Farmer, M. T.; Kilsdonk, D. J.; Aeschlimann, R. W.; Basu, S. (Nuclear Engineering Division); (NRC)

    2011-05-23

    The Melt Attack and Coolability Experiments (MACE) program at Argonne National Laboratory addressed the issue of the ability of water to cool and thermally stabilize a molten core/concrete interaction (MCCI) when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the melt to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to melt quenching. However, due to the integral nature of these tests, several questions regarding the crust freezing behavior could not be adequately resolved. These questions include: (1) To what extent does water ingression into the crust increase the melt quench rate above the conduction-limited rate and how is this affected by melt composition and system pressure and (2) What is the fracture strength of the corium crust when subjected to a thermal-mechanical load and how does it depend upon the melt composition? A series of separate-effects experiments are being conducted to address these issues. The first employs an apparatus designed to measure the quench rate of a pool of corium ({approx}{phi}30 cm; up to 20 cm deep). The main parameter to be varied in these quench tests is the melt composition since it is thought to have a critical influence on the crust cracking behavior which, in turn, alters quench rate. The issue of crust strength will be addressed with a second apparatus designed to mechanically load the crust produced by the quench tests. This apparatus will measure the fracture strength of the crust while under a thermal load created by a heating element beneath the crust. The two apparatuses used to measure the melt quench rate and crust strength are jointly referred to as SSWICS (Small-Scale Water Ingression and Crust Strength). This report describes results of the second water ingression test, designated SSWICS-2. The report includes a description of the test apparatus, the

  18. OECD MCCI project Small-Scale Water Ingression and Crust Strength Tests (SSWICS) SSWICS-1 test data report : thermal hydraulic results. Rev. 0 September 20, 2002.

    Energy Technology Data Exchange (ETDEWEB)

    Lomperski, S.; Farmer, M. T.; Kilsdonk, D. J.; Aeschlimann, R. W.; Basu, S. (Nuclear Engineering Division); (NRC)

    2011-05-23

    The Melt Attack and Coolability Experiments (MACE) program at Argonne National Laboratory addressed the issue of the ability of water to cool and thermally stabilize a molten core/concrete interaction (MCCI) when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the melt to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to melt quenching. However, due to the integral nature of these tests, several questions regarding the crust freezing behavior could not be adequately resolved. These questions include: (1) To what extent does water ingression into the crust increase the melt quench rate above the conduction-limited rate and how is this affected by melt composition and system pressure and (2) What is the fracture strength of the corium crust when subjected to a thermal-mechanical load and how does it depend upon the melt composition? A series of separate-effects experiments are being conducted to address these issues. The first employs an apparatus designed to measure the quench rate of a pool of corium ({approx}{phi}30 cm; up to 20 cm deep). The main parameter to be varied in these quench tests is the melt composition since it is thought to have a critical influence on the crust cracking behavior which, in turn, alters quench rate. The issue of crust strength will be addressed with a second apparatus designed to mechanically load the crust produced by the quench tests. This apparatus will measure the fracture strength of the crust while under a thermal load created by a heating element beneath the crust. The two apparatuses used to measure the melt quench rate and crust strength are jointly referred to as SSWICS (Small-Scale Water Ingression and Crust Strength). This report describes results of the first water ingression test, designated SSWICS-1. The report includes a description of the test apparatus, the

  19. The USGS Earthquake Scenario Project

    Science.gov (United States)

    Wald, D. J.; Petersen, M. D.; Wald, L. A.; Frankel, A. D.; Quitoriano, V. R.; Lin, K.; Luco, N.; Mathias, S.; Bausch, D.

    2009-12-01

    The U.S. Geological Survey’s (USGS) Earthquake Hazards Program (EHP) is producing a comprehensive suite of earthquake scenarios for planning, mitigation, loss estimation, and scientific investigations. The Earthquake Scenario Project (ESP), though lacking clairvoyance, is a forward-looking project, estimating earthquake hazard and loss outcomes as they may occur one day. For each scenario event, fundamental input includes i) the magnitude and specified fault mechanism and dimensions, ii) regional Vs30 shear velocity values for site amplification, and iii) event metadata. A grid of standard ShakeMap ground motion parameters (PGA, PGV, and three spectral response periods) is then produced using the well-defined, regionally-specific approach developed by the USGS National Seismic Hazard Mapping Project (NHSMP), including recent advances in empirical ground motion predictions (e.g., the NGA relations). The framework also allows for numerical (3D) ground motion computations for specific, detailed scenario analyses. Unlike NSHMP ground motions, for ESP scenarios, local rock and soil site conditions and commensurate shaking amplifications are applied based on detailed Vs30 maps where available or based on topographic slope as a proxy. The scenario event set is comprised primarily by selection from the NSHMP events, though custom events are also allowed based on coordination of the ESP team with regional coordinators, seismic hazard experts, seismic network operators, and response coordinators. The event set will be harmonized with existing and future scenario earthquake events produced regionally or by other researchers. The event list includes approximate 200 earthquakes in CA, 100 in NV, dozens in each of NM, UT, WY, and a smaller number in other regions. Systematic output will include all standard ShakeMap products, including HAZUS input, GIS, KML, and XML files used for visualization, loss estimation, ShakeCast, PAGER, and for other systems. All products will be

  20. Emissions scenarios: a final response

    Energy Technology Data Exchange (ETDEWEB)

    Gruebler, A.; Nakicenovic, N.; Alcamo, J. (and others)

    2004-01-01

    This note is a final response to the debate raised by Mr. Castles and Mr. Henderson (for brevity, we refer here to the two authors simply as C and H) in this Journal (vol 14, no 2 and 3, and no 4) on the issue of economic growth in developing countries in some of the emissions scenarios published in the IPCC Special Report on Emissions Scenarios (SRES) (Nakicenovic et al., 2000). We first outline areas of agreement and then the remaining areas of disagreement. Two important areas of agreement have emerged from the debate according to our view. First, both parties agree that scenarios assuming a conditional convergence in income levels, i.e., a higher growth in per capita income in poorer countries when compared to countries with higher levels of affluence, are both 'plausible and well attested in economic history' (C and H, p. 424). Thus, the fundamental, structural characteristic of some of the SRES scenarios contested by C and H are not challenged per se, but rather how fast such trends could unfold in the future. (author)

  1. Emissions scenario: a final response

    Energy Technology Data Exchange (ETDEWEB)

    Gruebler, A.; Nakicenovic, N.; Alcamo, J. (and others)

    2004-01-01

    This note is a final response to the debate raised by Mr Castles and Mr Henderson (for brevity, we refer here to the two authors simply as C and H) in this Journal (vol. 14, no. 2 and 3, and no. 4) on the issue of economic growth in developing countries in some of the emissions scenarios published in the IPCC Special Report on Emissions Scenarios (SRES) (Nakicenovic et al., 2000). We first outline areas of agreement and then the remaining areas of disagreement. Two important areas of agreement have emerged from the debate according to our view. First, both parties agree that scenarios assuming a conditional convergence in income levels, i.e., a higher growth in per capita income in poorer countries when compared to countries with higher levels of affluence, are both ''plausible and well attested in economic history'' (C and H, p. 424). Thus, the fundamental, structural characteristic of some of the SRES scenarios contested by C and H are not challenged per se, but rather how fast such trends could unfold in the future. (author)

  2. Chemical evolution in hierarchical scenarios

    OpenAIRE

    Tissera P.B.

    2012-01-01

    We studied the chemical properties of Milky-Way mass galaxies. We found common global chemical patterns with particularities which reflect their different assembly histories in a hierarchical scenario. We carried out a comprehensively analysis of the dynamical components (central spheroid, disc, inner and outer haloes) and their chemical properties.

  3. Rapid scenarios and observed intensities

    Directory of Open Access Journals (Sweden)

    Franco Pettenati

    2012-10-01

    Full Text Available After a destructive earthquake, national Governments need to know the approximate amount of damage, the number of casualties, and the financial losses as soon as possible. Rapid scenarios are also used to inform the general public; see the widely used Shakemap package [Wald et al. 1999, 2006] of the US Geological Survey (USGS and the one modified by the Istituto Nazionale di Geofisica e Vulcanologia (INGV; National Institute of Geophysics and Volcanology, which is reproduced for Figure 1. The general matter of the use of intensities in damage scenarios was discussed in a special session at the 2008 Annual Meeting of the Seismological Society of America (http://www.seismosoc.org/meetings/2008/specialsessions.html, and was also discussed in the NIS-1 session of the European Congress in Moscow, in August 2012 (http://www.esc2012-moscow.org/esc_thematicareas.html. The purposes of the present report are to: (i compare different types of intensities; (ii check two rapid scenarios of intensity; and (iii understand whether the KF formula [Sirovich 1996, Sirovich et al. 2009] can be used as a new 'attenuation' relationship to improve rapid scenarios. […

  4. Future Scenarios and Environmental Education

    Science.gov (United States)

    Kopnina, Helen

    2014-01-01

    This article explores a number of questions about visions of the future and their implications for environmental education (EE). If the future were known, what kind of actions would be needed to maintain the positive aspects and reverse the negative ones? How could these actions be translated into the aims of EE? Three future scenarios are…

  5. Scenario Based Network Infrastructure Planning

    DEFF Research Database (Denmark)

    Knudsen, Thomas Phillip; Pedersen, Jens Myrup; Madsen, Ole Brun

    2005-01-01

    The paper presents a method for IT infrastructure planning that take into account very long term developments in usages. The method creates a scenario for a final, time independent stage in the planning process. The method abstracts relevant modelling factors from available information; this...

  6. Helical ITER hybrid scenario equilibria

    International Nuclear Information System (INIS)

    Numerical computations of ITER equilibria in the hybrid scenario using a three-dimensional (3D) magnetohydrodynamic equilibrium code with nested magnetic flux surfaces demonstrate the formation of internal 3D helical cores similar to saturated ideal internal kink modes under reversed magnetic shear conditions when the minimum value of the inverse rotational transform is in the neighbourhood of unity.

  7. Ultra-Perfect Sorting Scenarios

    Science.gov (United States)

    Ouangraoua, Aïda; Bergeron, Anne; Swenson, Krister M.

    Perfection has been used as a criteria to select rearrangement scenarios since 2004. However, there is a fundamental bias towards extant species in the original definition: ancestral species are not bound to perfection. Here we develop a new theory of perfection that takes an egalitarian view of species, and apply it to the complex evolution of mammal chromosome X.

  8. Shell energy scenarios to 2050

    International Nuclear Information System (INIS)

    Shell developed two scenarios that describe alternative ways the energy future may develop. In the first scenario (Scramble) policymakers pay little attention to more efficient energy use until supplies are tight. Likewise, greenhouse gas emissions are not seriously addressed until there are major climate shocks. In the second scenario (Blueprints) growing local actions begin to address the challenges of economic development, energy security and environmental pollution. A price is applied to a critical mass of emissions giving a huge stimulus to the development of clean energy technologies, such as carbon dioxide capture and storage, and energy efficiency measures. The result is far lower carbon dioxide emissions. Both these scenarios can help Shell to test their strategy against a range of possible developments over the long-term. However, according to Shell, the Blueprints' outcomes offer the best hope for a sustainable future, whether or not they arise exactly in the way described. However, with the right combination of policy, technology and commitment from governments, industry and society globally, Shell believes it can be realized. But achieving the targets will not be easy, and time is short. Clear thinking, huge investment, and effective leadership are required

  9. NEC-2020 emission reduction scenarios

    DEFF Research Database (Denmark)

    Slentø, Erik; Nielsen, Ole-Kenneth; Hoffmann, Leif;

    The upcoming NEC-2020 EU directive sets up emission ceilings for NOX, SO2, NH3, NMVOC and PM in order to meet the environmental exposure targets of the Thematic Strategy. This report contains an assessment of intermediary emission reduction scenarios for Denmark, computed by the GAINS model 2007...

  10. Particle Production in Ekpyrotic Scenarios

    CERN Document Server

    Hipolito-Ricaldi, W S; Ferreira, Elisa G M; Graef, L L

    2016-01-01

    We consider Parker particle production in the Ekpyrotic scenario (in particular in the New Ekpyrotic model) and show that the density of particles produced by the end of the phase of Ekpyrotic contraction is sufficient to lead to a hot state of matter after the bounce. Hence, no separate reheating mechanism is necessary.

  11. Scenario/Class Diagram Synthesis

    OpenAIRE

    Prabhune, Aniket; Mahajan, Reenal; Singhal, Mudita

    2003-01-01

    The scenario-synthesis problem in requirements analysis is explored in this report.The approach suggested by Khriss et al.is adapted for the domain of Digital Libraries. The results of the synthesis along with the entire transformation process are elaborated in this report.

  12. Use of a multi-species reactive transport model to simulate chloride ingress in mortar exposed to NaCl solution or sea-water

    DEFF Research Database (Denmark)

    Jensen, Mads Mønster; De Weerdt, K.; Johannesson, Björn;

    2015-01-01

    Simulations of ion ingress in Portland cement mortar using a multi-species reactive mass transport model are compared with experimental test results. The model is an extended version of the Poisson–Nernst–Planck equations, accounting for chemical equilibrium. Saturated mortar samples were exposed...... reactive mass transport model is shown by comparing the simulation and experimental results. The tortuosity factor used in the simulations is adjusted to obtain the best reproduction of the experimental results. The model predicts the total chloride content satisfactorily, despite assumptions in the...... simulation like fixed hydration degree over time. Improvements and suggestions for further development of the model are discussed, e.g. extended hydration description, improved overall chemical description and a more strict use of the tortuosity factor....

  13. Reduction in cobalt ingress from fuelling machine stellite wear products into primary heat transport system: results from modeling assessment of ion exchange clean-up

    International Nuclear Information System (INIS)

    This paper presents an analysis of the benefit of installing ion exchange capability in the heavy water auxiliary system of a Darlington fuelling machine. An overall mass balance model was developed to estimate the potential reduction in cobalt ingress from the fuelling machine into the primary heat transport system. The analysis considered generation terms from a) on-going ram ball wear and b) dissolution from the surfaces of trapped filter particulates as well as from ram ball surfaces and removal terms arising from a) flow injection into the reactor system, b) filtration and c) ion exchange. Model equations were solved for each activity in the fueling cycle to determine the aggregate behavior over an extended period of operation. Results from model calculations suggest that, without ion exchange provisions, about 16.7 g/year of cobalt enters the reactor system from each fuelling machine. The majority of this cobalt (66%) is in particulate form with the balance being in dissolved form (soluble as well as colloidal). Most of the dissolved cobalt (80 %) is generated from the surfaces of the ram balls, the remainder being from the surfaces of the trapped filter particulates. The potential reduction in cobalt ingress from ion exchange operation was estimated to be 21% or 3.5 g/year per fuelling machine. Based on a postulated growth curve for the Co-60 reactor face fields, estimates were also obtained for the net plant dose savings that would result from ion exchange operation. This was estimated for the period 2010 - 2022 to exceed 480 rem. Based on the analysis performed, installation of ion exchange purification capability in the heavy water auxiliary system is strongly recommended. (author)

  14. Local and regional low carbon scenarios methodology, challenges and opportunities

    International Nuclear Information System (INIS)

    In its first part, this report discusses the emergence of local climate and energy policy in Europe, the implementation of nationally imposed but regionally anchored energy scenarios (i.e. in France, the Climate Air Energy Regional Schemes or SRCAE). Then it addresses the methodological and political aspects of local and regional low emission scenarios: methodologies and typologies of energy scenarios, ways to define an appropriate emission reduction and energy consumption objective, ways to deal with emission or carbon gaps, ways to make local emission inventories, ways to gather local data, ways to deal with special emission sources, ways to assess and develop local energy efficiency and renewable energy potentials, ways to take energy sufficiency into account, and the evolution from energy autonomy to 100% renewable energy territories. The last part addresses the issues of stake holder and citizen participation in the definition of long term strategies

  15. Modelling internal air systems in gas turbine engines

    Institute of Scientific and Technical Information of China (English)

    J Michael Owen

    2007-01-01

    Rotating-disc systems can be used to model,experimentally and computationally,the flow and heat transfer that occur inside the internal cooling-air systems of gas turbine engines.These rotating-disc systems have been used successfully to simplify and understand some of the complex flows that occur in internal-air systems,and designers have used this insight to improve the cooling effectiveness,thereby increasing the engine efficiency and reducing the emissions.In this review paper,three important cases are considered:hot-gas ingress;the pre-swirl system;and buoyancy-induced flow.Ingress,or ingestion,occurs when hot gas from the mainstream gas path is ingested into the wheel-space between the turbine disc and its adjacent casing.Rim seals are fitted at the periphery of the system,and sealing flow is used to reduce or prevent ingress.However,too much sealing air reduces the engine efficiency,and too little can cause serious overheating,resulting in damage to the turbine rim and blade roots.Although the flow is three-dimensional and unsteady,there are encouraging signs that simple 'orifice models' could be used to estimate the amount of ingress into the wheel-space.In a pre-swirl system,the cooling air for the gas-turbine blades is swirled by stationary nozzles,and the air is delivered to the blades via receiver holes in the rotating turbine disc.Swirling the air reduces its temperature relative to the rotating blades,and the designer needs to calculate the air temperature and pressure drop in the system.The designer also needs to calculate the effect of this swirling flow on the heat transfer from the turbine disc to the air,as this has a significant effect on the temperature distribution and stresses in the disc.Recent experimental and computational studies have given a better understanding of the flow and heat transfer in these systems.Buoyancy-induced flow occurs in the cavity between two co-rotating compressor discs when the temperature of the discs is higher

  16. Air Pollution

    Science.gov (United States)

    Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, dust, ... a gas, is a major part of air pollution in cities. When ozone forms air pollution, it's ...

  17. Air Pollution

    Science.gov (United States)

    Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, dust, pollen and ... Ozone, a gas, is a major part of air pollution in cities. When ozone forms air pollution, ...

  18. The Danish Scenario Workshop Report

    DEFF Research Database (Denmark)

    Brodersen, Søsser; Jørgensen, Michael Søgaard

    workshop in March 2003 by identifying potential participants, producing informative material, sending out invitations, planning and arranging how the workshop were to be conducted and further to make follow-up efforts to ensure a sufficient amount of participants in each Interest group. A total of 22...... participants (excluded the two moderators) participated in the Danish scenario workshop. At the Danish scenario workshop we operated with five Interest groups: Science Shops, students, university researchers, civil society organisations and university policy makers. Each Interest group developed a positive and......: Knowledge and project processes: Knowledge sharing and dialogue in focus throughout the whole project co-operation. Follow-up activities after a project co-operation have ended. Salary to clients for supervision. The theme discussions were made in mixed groups, containing participants from each Interest...

  19. Comparing long term energy scenarios

    International Nuclear Information System (INIS)

    Major projection studies by international organizations and senior analysts have been compared with reference to individual key parameters (population, energy demand/supply, resources, technology, emissions and global warming) to understand trends and implications of the different scenarios. Then, looking at the long term (i.e., 2050 and beyond), parameters and trends have been compared together to understand and quantify whether and when possible crisis or market turbulence might occur due to shortage of resources or environmental problems

  20. Advanced scenarios for ITER operation

    International Nuclear Information System (INIS)

    In thermonuclear fusion research using magnetic confinement, the tokamak is the leading candidate for achieving conditions required for a reactor. An international experiment, ITER is proposed as the next essential and critical step on the path to demonstrating the scientific and technological feasibility of fusion energy. ITER is to produce and study plasmas dominated by self heating. This would give unique opportunities to explore, in reactor relevant conditions, the physics of α-particle heating, plasma turbulence and turbulent transport, stability limits to the plasma pressure and exhaust of power and particles. Important new results obtained in experiments, theory and modelling, enable an improved understanding of the physical processes occurring in tokamak plasmas and give enhanced confidence in ITER achieving its goals. In particular, progress has been made in research to raise the performance of tokamaks, aimed to extend the discharge pulse length towards steady-state operation (advanced scenarios). Standard tokamak discharges have a current density increasing monotonically towards the centre of the plasma. Advanced scenarios on the other hand use a modified current density profile. Different advanced scenarios range from (i) plasmas that sustain a central region with a flat current density profile (zero magnetic shear), capable of operating stationary at high plasma pressure, to (ii) discharges with an off axis maximum of the current density profile (reversed magnetic shear in the core), able to form internal transport barriers, to increase the confinement of the plasma. The physics of advanced tokamak discharges is described, together with an overview of recent results from different tokamak experiments. International collaboration between experiments aims to provide a better understanding, control and optimisation of these plasmas. The ability to explore advanced scenarios in ITER is very desirable, in order to verify the result obtained in experiments

  1. Scenarios and Strategies for Africa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-11-15

    In 2011, IRENA will start developing scenarios and strategies for Africa. This is a pilot study for a project that will ultimately encompass the whole world. The selection of Africa first indicates the priority that the IRENA work programme places on the continent. In the framework of the 2011 IRENA work programme, the analysis of scenarios and strategies will feed into the renewables readiness assessment, which will assess policy priorities and best practices in renewable energy policy-making. This, in turn, will be the basis for financing investment and capacity building activities. Energy policy advice must consider issues, such as the structure of energy supply and demand, the past and future energy trends, renewable energy resources, energy economics and technology access. Scenarios and strategies are key tools for such an analysis. Regional and national differences must be considered and individual sectors and end-use categories further analysed. These include power generation, cooking, heating, industrial process heat, and transport. Urban and rural solutions will be dealt with separately, as well as centralised and decentralised solutions. The analysis will cover issues, such as potentials, technology, supply chains and investment needs.

  2. Simulating geometrically complex blast scenarios

    Directory of Open Access Journals (Sweden)

    Ian G. Cullis

    2016-04-01

    Full Text Available The effects of blast waves generated by energetic and non-energetic sources are of continuing interest to the ballistics research community. Modern conflicts are increasingly characterised by asymmetric urban warfare, with improvised explosive devices (IEDs often playing a dominant role on the one hand and an armed forces requirement for minimal collateral effects from their weapons on the other. These problems are characterised by disparate length- and time-scales and may also be governed by complex physics. There is thus an increasing need to be able to rapidly assess and accurately predict the effects of energetic blast in topologically complex scenarios. To this end, this paper presents a new QinetiQ-developed advanced computational package called EAGLE-Blast, which is capable of accurately resolving the generation, propagation and interaction of blast waves around geometrically complex shapes such as vehicles and buildings. After a brief description of the numerical methodology, various blast scenario simulations are described and the results compared with experimental data to demonstrate the validation of the scheme and its ability to describe these complex scenarios accurately and efficiently. The paper concludes with a brief discussion on the use of the code in supporting the development of algorithms for fast running engineering models.

  3. Simulating geometrically complex blast scenarios

    Institute of Scientific and Technical Information of China (English)

    Ian G. CULLIS; Nikos NIKIFORAKIS; Peter FRANKL; Philip BLAKELY; Paul BENNETT; Paul GREENWOOD

    2016-01-01

    The effects of blast waves generated by energetic and non-energetic sources are of continuing interest to the ballistics research community. Modern conflicts are increasingly characterised by asymmetric urban warfare, with improvised explosive devices (IEDs) often playing a dominant role on the one hand and an armed forces requirement for minimal collateral effects from their weapons on the other. These problems are characterised by disparate length-and time-scales and may also be governed by complex physics. There is thus an increasing need to be able to rapidly assess and accurately predict the effects of energetic blast in topologically complex scenarios. To this end, this paper presents a new QinetiQ-developed advanced computational package called EAGLE-Blast, which is capable of accurately resolving the generation, propagation and interaction of blast waves around geometrically complex shapes such as vehicles and buildings. After a brief description of the numerical methodology, various blast scenario simulations are described and the results compared with experimental data to demonstrate the validation of the scheme and its ability to describe these complex scenarios accurately and efficiently. The paper concludes with a brief discussion on the use of the code in supporting the development of algorithms for fast running engineering models.

  4. Human health impacts for renewable energy scenarios from the EnerGEO Platform of Integrated Assessment (PIA)

    International Nuclear Information System (INIS)

    This article reports impact results from running the EnerGEO Platform of Integrated Assessment (PIA) related to human health for different scenarios in Europe. The scenarios were prepared within the EnerGEO project. The idea of this European project is to determine how low carbon scenarios, and in particular scenarios with a high share of renewable energy, affect concentrations of air pollutants and as a consequence affect human health. PM2.5 concentrations were estimated with the IIASA Greenhouse Gas and Air Pollution Interactions and Synergies (GAINS) model on a time horizon up to the year 2050 for different scenarios. We analyse here the estimation of the Loss of Life Expectancy due to PM2.5 concentrations for the Baseline scenario taken as a reference and the Maximum renewable power scenario. (orig.)

  5. Modeling the global society-biosphere-climate system. Part 2: computed scenarios

    International Nuclear Information System (INIS)

    This paper presents scenarios computed with IMAGE 2.0, an integrated model of the global environment and climate change. Results are presented for selected aspects of the society-biosphere-climate system including primary energy consumption, emissions of various greenhouse gases, atmospheric concentrations of gases, temperature, precipitation, land cover and other indicators. Included are a 'Conventional Wisdom' scenario, and three variations of this scenario: (i) the Conventional Wisdom scenario is a reference case which is partly based on the input assumptions of the IPCC's IS92a scenario; (ii) the 'Biofuel Crops' scenario assumes that most biofuels will be derived from new cropland; (iii) the 'No Biofuels' scenario examines the sensitivity of the system to the use of biofuels; and (iv) the 'Ocean Realignment' scenario investigates the effect of a large-scale change in ocean circulation on the biosphere and climate. Results of the biofuel scenarios illustrate the importance of examining the impact of biofuels on the full range of greenhouse gases, rather than only CO2. These scenarios also indicate possible side effects of the land requirements for energy crops. The Ocean Realignment scenario shows that an unexpected, low probability event can both enhance the build-up of greenhouse gases, and at the same time cause a temporary cooling of surface air temperatures in the Northern Hemisphere. However, warming of the atmosphere is only delayed, not avoided. 26 refs., 16 figs., 7 tabs

  6. Designing Asteroid Impact Scenario Trajectories

    Science.gov (United States)

    Chodas, Paul

    2016-05-01

    In order to study some of the technical and geopolitical issues of dealing with an asteroid on impact trajectory, a number of hypothetical impact scenarios have been presented over the last ten years or so. These have been used, for example, at several of the Planetary Defense Conferences (PDCs), as well as in tabletop exercises with the Federal Emergency Management Agency (FEMA), along with other government agencies. The exercise at the 2015 PDC involved most of the attendees, consisted of seven distinct steps (“injects”), and with all the presentations and discussions, took up nearly 10 hours of conference time. The trajectory for the PDC15 scenario was entirely realistic, and was posted ahead of the meeting. It was made available in the NEO Program’s Horizons ephemeris service so that users could , for example, design their own deflection missions. The simulated asteroid and trajectory had to meet numerous very exacting requirements: becoming observable on the very first day of the conference, yet remaining very difficult to observe for the following 7 years, and far enough away from Earth that it was out of reach of radar until just before impact. It had to be undetectable in the past, and yet provide multiple perihelion opportunities for deflection in the future. It had to impact in a very specific region of the Earth, a specific number of years after discovery. When observations of the asteroid are simulated to generate an uncertainty region, that entire region must impact the Earth along an axis that cuts across specific regions of the Earth, the “risk corridor”. This is important because asteroid deflections generally move an asteroid impact point along this corridor. One scenario had a requirement that the asteroid pass through a keyhole several years before impact. The PDC15 scenario had an additional constraint that multiple simulated kinetic impactor missions altered the trajectory at a deflection point midway between discovery and impact

  7. Potential of ANSYS CFX 12 for the determination of the minimum cover of pump intake nozzles to avoid air entrainment

    International Nuclear Information System (INIS)

    For a reliable and economic pump operation the homogeneous fluid influx is an important parameter. Unfavorable influx conditions cause vibrations, noise development, decrease or breakdown of the delivery rate and increased power consumption. Very often air ingress due to turbulences in the intake region of the pump is causing the disturbances. The authors show that the CFD code ABSYS CFX 12 allows - at least for rotation-free inlet flow - to identify the water surface deformation and to determine the required minimum water cover to avoid air entrainment. Further mesh refinement and improved modeling of the two-phase flow could enhance the quantitative agreement with experimental data.

  8. On numerical calculation of an assimilation factor of variable heat ingress at automation of microclimate systems (rus

    Directory of Open Access Journals (Sweden)

    Azivskaya S.S.

    2011-08-01

    Full Text Available In the paper the nature of activity of the automated ventilating systems and air conditionings (V and AC under condition of their regulation "on deviation" is reviewed. The analysis of processes descending in V and AC and maintained room is given. The outcomes of numerical calculation of a non-steady thermal mode of a room with the computer program designed by authors are adduced. The confrontation of the obtained outcomes to the data designed before an approximated analytical technique is conducted. The identification of analytical model with selection of best values of numerical constants is carried out. The presentation is illustrated by a significant amount of a graphic stuff.

  9. Europa Explorer Operational Scenarios Development

    Science.gov (United States)

    Lock, Robert E.; Pappalardo, Robert T.; Clark, Karla B.

    2008-01-01

    In 2007, NASA conducted four advanced mission concept studies for outer planets targets: Europa, Ganymede, Titan and Enceladus. The studies were conducted in close cooperation with the planetary science community. Of the four, the Europa Explorer Concept Study focused on refining mission options, science trades and implementation details for a potential flagship mission to Europa in the 2015 timeframe. A science definition team (SDT) was appointed by NASA to guide the study. A JPL-led engineering team worked closely with the science team to address 3 major focus areas: 1) credible cost estimates, 2) rationale and logical discussion of radiation risk and mitigation approaches, and 3) better definition and exploration of science operational scenario trade space. This paper will address the methods and results of the collaborative process used to develop Europa Explorer operations scenarios. Working in concert with the SDT, and in parallel with the SDT's development of a science value matrix, key mission capabilities and constraints were challenged by the science and engineering members of the team. Science goals were advanced and options were considered for observation scenarios. Data collection and return strategies were tested via simulation, and mission performance was estimated and balanced with flight and ground system resources and science priorities. The key to this successful collaboration was a concurrent development environment in which all stakeholders could rapidly assess the feasibility of strategies for their success in the full system context. Issues of science and instrument compatibility, system constraints, and mission opportunities were treated analytically and objectively leading to complementary strategies for observation and data return. Current plans are that this approach, as part of the system engineering process, will continue as the Europa Explorer Concept Study moves toward becoming a development project.

  10. Scenarios for the future; Framtidsscenarier

    Energy Technology Data Exchange (ETDEWEB)

    Haegermark, H.; Bergmark, M.

    1995-06-01

    This project aims primarily to give a basis for the joint R and D program for the Swedish electric utility industry, in the form of pictures of the future up to 2020. The work was performed during four seminars in a group of managers and R and D planners. The four scenarios differ mainly in the assumptions of high or low economic growth and on market or political rule. Assumptions on essential uncertainties about the future have been combined in a consistent manner, e.g. on the structure of the utility industry, the role of nuclear power, the importance of the greenhouse gas issue, the influence of new technology developments and on changes of values in society. Certain other development appear in all scenarios, e.g. the impact of information technology throughout society, the internationalization of business in general and industrial production in particular, considerations for the environment and care for natural resources. The four scenarios are: `Technology on the throne` (market rule/high growth); `Intense competition` (market rule/low growth); `Monopoly takes over` (political rule/high growth); and `Green local society` (political rule/low growth). Some of the important factors pointed out by the study are: Increased customer mobility between regions and countries; The impact of information technology; Societal value changes; Sustainable development as an important driving force; Structure of the utility industry. Diversifying into new services. New players; Access to knowledge and competence; Ways for handling the greenhouse gas problem; Preparedness for nuclear power phase-out. 12 figs, 6 tabs

  11. Emergent physics: Fermi point scenario

    CERN Document Server

    Volovik, G E

    2008-01-01

    The Fermi-point scenario of emergent gravity has the following consequences: gravity emerges together with fermionic and bosonic matter; emergent fermionic matter consists of massless Weyl fermions; emergent bosonic matter consists of gauge fields; Lorentz symmetry persists well above the Planck energy; space-time is naturally 4-dimensional; Universe is naturally flat; cosmological constant is naturally small or zero; underlying physics is based on discrete symmetries; `quantum gravity' cannot be obtained by quantization of Einstein equations; there is no contradiction between quantum mechanics and gravity; etc.

  12. Climate protection scenario 2050. Summary

    International Nuclear Information System (INIS)

    The report on the meeting of the experts on modeling of the climate protection scenario 2050 summarizes the substantial results: 80-90% reduction the greenhouse gas emissions means a reduction of fossil energy carriers by up to 98%. The electricity generation industry has to provide most of the reduction since esp. agriculture cannot reduce the CO2 emissions. The amount of renewable energy for electricity production has to increase to about 95%. The economic analysis shows that a strategy of energy efficiency and electricity production from renewable energy sources plus product innovation is a no-regret strategy that will be advantageous for Germany in a long-term.

  13. Climate impacts of the ECLIPSE future emissions mitigation scenario

    Science.gov (United States)

    Baker, Laura; Collins, Bill; Olivie, Dirk; Cherian, Ribu; Quaas, Johannes; Myhre, Gunnar; Hodnebrog, Oivind; Skeie, Ragnhild

    2016-04-01

    We investigate the possible near-term climate benefits from mitigating aerosols, ozone and methane. The ECLIPSE (Evaluating the Climate and Air Quality Impacts of Short-Lived Pollutants) project developed a realistic emissions inventory based on current legislation for 2005-2050 (CLE), and a corresponding mitigation scenario designed to be beneficial for both air quality and short-term climate impact (MIT). We determine the climate impacts of the MIT scenario, focussing on the period 2040-2050. Four climate models with interactive chemistry and aerosols (HadGEM, NorESM, CESM-CAM4 and ECHAM-HAM) are used to provide multi-model ensembles of both atmosphere-only and coupled atmosphere-ocean simulations, to separate the effective radiative forcing (ERF) and the climate response. The ERFs are derived from the atmosphere-only simulations. In all models the MIT scenario leads to a negative global ERF which is driven mainly by methane emissions reductions. There is variability between models in the relative importance of methane and aerosol emissions reductions, and in the sign of ERF response to aerosol emissions reductions. The climate response to MIT is derived from the coupled simulations. In all models, MIT results in a decrease in the global mean temperature compared to CLE, with a model mean decrease of 0.22°C. The temperature decrease is seen most strongly in the Northern Hemisphere and is particularly strong in the Arctic. The ensembles of coupled-ocean simulations have therefore enabled us to identify a robust cooling signal from the air quality mitigation scenarios, which can be attributed to the different species using the ERFs.

  14. Trust and the illusive force of scenarios

    DEFF Research Database (Denmark)

    Selin, Cynthia Lea

    2006-01-01

    Scenarios are typically defined as stories describing different but equally plausible futures that are developed using methods that systematically gather perceptions about certainties and uncertainties. Scenarios are not intended to be truthful, but rather provocative and helpful in strategy form...

  15. Study on scenario evaluation methodology for decommissioning nuclear facilities using fuzzy logic

    International Nuclear Information System (INIS)

    Since there are many scenarios of the process from start to completion of a decommissioning project, it is important to study scenarios of decommissioning by evaluating such properties as safety, cost, and technology. An optimum scenario with the highest feasibility in accordance with the facility and environmental conditions should be selected on the basis of the results of the study. For analyzing a scenario of decommissioning, we prepared structured work packages by using the work breakdown structures (WBS) method together with qualitative evaluation of the technologies being applied to work packages located at the bottom (the third level) of the WBS. A calculation model was constructed to evaluate the feasibility of a scenario where fuzzy logic is applied to derive a score of technology performance and TOPSIS is applied for getting a feasibility grade of the scenario from technical performance scoring. As a case study, the model was applied to the debris removal scenario of Fukushima Daiichi Nuclear Power Plant to confirm its applicability. Two scenarios, underwater and in-air debris removal cases, were characterized by extracting the work packages with the lowest feasibility and by obtaining total average scores of the scenarios. It is confirmed that the methodology developed is useful for the scenario evaluation of decommissioning nuclear facilities. (author)

  16. Co-benefits of air quality and climate change policies on air quality of the Mediterranean

    Science.gov (United States)

    Pozzoli, Luca; Mert Gokturk, Ozan; Unal, Alper; Kindap, Tayfun; Janssens-Maenhout, Greet

    2015-04-01

    The Mediterranean basin is one of the regions of the world where significant impacts due to climate changes are predicted to occur in the future. Observations and model simulations are used to provide to the policy makers scientifically based estimates of the necessity to adjust national emission reductions needed to achieve air quality objectives in the context of a changing climate, which is not only driven by GHGs, but also by short lived climate pollutants, such as tropospheric ozone and aerosols. There is an increasing interest and need to design cost-benefit emission reduction strategies, which could improve both regional air quality and global climate change. In this study we used the WRF-CMAQ air quality modelling system to quantify the contribution of anthropogenic emissions to ozone and particulate matter concentrations in Europe and the Eastern Mediterranean and to understand how this contribution could change in different future scenarios. We have investigated four different future scenarios for year 2050 defined during the European Project CIRCE: a "business as usual" scenario (BAU) where no or just actual measures are taken into account; an "air quality" scenario (BAP) which implements the National Emission Ceiling directive 2001/81/EC member states of the European Union (EU-27); a "climate change" scenario (CC) which implements global climate policies decoupled from air pollution policies; and an "integrated air quality and climate policy" scenario (CAP) which explores the co-benefit of global climate and EU-27 air pollution policies. The BAP scenario largely decreases summer ozone concentrations over almost the entire continent, while the CC and CAP scenarios similarly determine lower decreases in summer ozone but extending all over the Mediterranean, the Middle East countries and Russia. Similar patterns are found for winter PM concentrations; BAP scenario improves pollution levels only in the Western EU countries, and the CAP scenario determines

  17. The Negawatt association reevaluates its energy scenario

    International Nuclear Information System (INIS)

    In 2003 the association Negawatt imagined an energy policy scenario (2000-2050) which aims to divide by four the greenhouse gases emission. This scenario has just been completed for the 2006 edition with less growth evolution. This scenario expects the gradually shutdown of nuclear power plants for 2035, without the replacement by power plants of third generation. (A.L.B.)

  18. Air Abrasion

    Science.gov (United States)

    ... delivered directly to your desktop! more... What Is Air Abrasion? Article Chapters What Is Air Abrasion? What Happens? The Pros and Cons Will I Feel Anything? Is Air Abrasion for Everyone? print full article print this ...

  19. The ShakeOut Scenario

    Science.gov (United States)

    Jones, Lucile M.; Bernknopf, Richard; Cox, Dale; Goltz, James; Hudnut, Kenneth; Mileti, Dennis; Perry, Suzanne; Ponti, Daniel; Porter, Keith; Reichle, Michael; Seligson, Hope; Shoaf, Kimberley; Treiman, Jerry; Wein, Anne

    2008-01-01

    This is the initial publication of the results of a cooperative project to examine the implications of a major earthquake in southern California. The study comprised eight counties: Imperial, Kern, Los Angeles, Orange, Riverside, San Bernardino, San Diego, and Ventura. Its results will be used as the basis of an emergency response and preparedness exercise, the Great Southern California ShakeOut, and for this purpose we defined our earthquake as occurring at 10:00 a.m. on November 13, 2008. As members of the southern California community use the ShakeOut Scenario to plan and execute the exercise, we anticipate discussion and feedback. This community input will be used to refine our assessment and will lead to a formal publication in early 2009. Our goal in the ShakeOut Scenario is to identify the physical, social and economic consequences of a major earthquake in southern California and in so doing, enable the users of our results to identify what they can change now?before the earthquake?to avoid catastrophic impact after the inevitable earthquake occurs. To do so, we had to determine the physical damages (casualties and losses) caused by the earthquake and the impact of those damages on the region?s social and economic systems. To do this, we needed to know about the earthquake ground shaking and fault rupture. So we first constructed an earthquake, taking all available earthquake research information, from trenching and exposed evidence of prehistoric earthquakes, to analysis of instrumental recordings of large earthquakes and the latest theory in earthquake source physics. We modeled a magnitude (M) 7.8 earthquake on the southern San Andreas Fault, a plausible event on the fault most likely to produce a major earthquake. This information was then fed forward into the rest of the ShakeOut Scenario. The damage impacts of the scenario earthquake were estimated using both HAZUS-MH and expert opinion through 13 special studies and 6 expert panels, and fall into four

  20. Benchmark scenarios for the NMSSM

    CERN Document Server

    Djouadi, A; Ellwanger, U; Godbole, R; Hugonie, C; King, S F; Lehti, S; Moretti, S; Nikitenko, A; Rottlander, I; Schumacher, M; Teixeira, A

    2008-01-01

    We discuss constrained and semi--constrained versions of the next--to--minimal supersymmetric extension of the Standard Model (NMSSM) in which a singlet Higgs superfield is added to the two doublet superfields that are present in the minimal extension (MSSM). This leads to a richer Higgs and neutralino spectrum and allows for many interesting phenomena that are not present in the MSSM. In particular, light Higgs particles are still allowed by current constraints and could appear as decay products of the heavier Higgs states, rendering their search rather difficult at the LHC. We propose benchmark scenarios which address the new phenomenological features, consistent with present constraints from colliders and with the dark matter relic density, and with (semi--)universal soft terms at the GUT scale. We present the corresponding spectra for the Higgs particles, their couplings to gauge bosons and fermions and their most important decay branching ratios. A brief survey of the search strategies for these states a...

  1. Radiation Detection Computational Benchmark Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Shaver, Mark W.; Casella, Andrew M.; Wittman, Richard S.; McDonald, Ben S.

    2013-09-24

    Modeling forms an important component of radiation detection development, allowing for testing of new detector designs, evaluation of existing equipment against a wide variety of potential threat sources, and assessing operation performance of radiation detection systems. This can, however, result in large and complex scenarios which are time consuming to model. A variety of approaches to radiation transport modeling exist with complementary strengths and weaknesses for different problems. This variety of approaches, and the development of promising new tools (such as ORNL’s ADVANTG) which combine benefits of multiple approaches, illustrates the need for a means of evaluating or comparing different techniques for radiation detection problems. This report presents a set of 9 benchmark problems for comparing different types of radiation transport calculations, identifying appropriate tools for classes of problems, and testing and guiding the development of new methods. The benchmarks were drawn primarily from existing or previous calculations with a preference for scenarios which include experimental data, or otherwise have results with a high level of confidence, are non-sensitive, and represent problem sets of interest to NA-22. From a technical perspective, the benchmarks were chosen to span a range of difficulty and to include gamma transport, neutron transport, or both and represent different important physical processes and a range of sensitivity to angular or energy fidelity. Following benchmark identification, existing information about geometry, measurements, and previous calculations were assembled. Monte Carlo results (MCNP decks) were reviewed or created and re-run in order to attain accurate computational times and to verify agreement with experimental data, when present. Benchmark information was then conveyed to ORNL in order to guide testing and development of hybrid calculations. The results of those ADVANTG calculations were then sent to PNNL for

  2. Some perspective decisions for the regeneration system equipment of the thermal and nuclear power plants decreasing the probability of water ingress into the turbine and rotor acceleration by return steam flow

    Science.gov (United States)

    Trifonov, N. N.; Svyatkin, F. A.; Sintsova, T. G.; Ukhanova, M. G.; Yesin, S. B.; Nikolayenkova, E. K.; Yurchenko, A. Yu.; Grigorieva, E. B.

    2016-03-01

    The regeneration system heaters are one of the sources of possible ingress of the water into the turbine. The water penetrates into the turbine either at the heaters overflow or with the return flow of steam generated when the water being in the heater boils up in the dynamic operation modes or at deenergization of the power-generating unit. The return flow of steam and water is dangerous to the turbine blades and can result in the rotor acceleration. The known protective devices used to prevent the overflow of the low-pressure and high-pressure heaters (LPH and HPH), of the horizontal and vertical heaters of heating-system water (HWH and VWH), as well as of the deaerators and low-pressure mixing heaters (LPMH) were considered. The main protective methods of the steam and water return flows supplied by the heaters in dynamic operation modes or at deenergization of the power-generating unit are described. Previous operating experience shows that the available protections do not fully prevent water ingress into the turbine and the rotor acceleration and, therefore, the development of measures to decrease the possibility of ingress of the water into the turbine is an actual problem. The measures allowing eliminating or reducing the water mass in the heaters are expounded; some of them were designed by the specialists of OAO Polzunov Scientific and Development Association on Research and Design of Power Equipment (NPO CKTI) and are efficiently introduced at heat power plants and nuclear power plants. The suggested technical solutions allow reducing the possibility of the water ingress into the turbine and rotor acceleration by return steam flow in the dynamic operation modes or in the case of power generating unit deenergization. Some of these solutions have been tested in experimental-industrial exploitation and can be used in industry.

  3. Marine Ingressive Events Recorded in Epicontinental Sequences:Example from the Cretaceous Songliao Basin of NE China in Comparison with the Triassic Central Europe Basin of SW Germany

    Institute of Scientific and Technical Information of China (English)

    WANG Pujun; LIU Wanzhu; YIN Xiuzhen; SCHNEIDER Werner; MATTERN Frank

    2002-01-01

    Songliao Basin is filled predominantly with continental facies sediments including alluvial fan, fluvial plain, fan delta, lacustrine delta, shore - shallow lacustrine, beach salty flat, semi - deep to deep lacustrine, subaqueous gravity flow,lacustrine swamp and pyroclastic sediments. However, some event units were formed during lake - marine linking periods of the Mid - Cretaceous in the basin, which include black shales with high values for salinity (Sr/Ba) , alkalinity ( Ca + Mg)/(Si + Al) , reducibility (Ni + Zn)/Ga and sulfide sulfur as well as heavy isotopes. The Breitenholz -section to be represented for facies comparison with the Cretaceous evaporitic series in Northeast China is localized in Southwest Germany. Stratigraphically it belongs to the Crabfeld Formation of Keuper of the Germanic Triassic corresponding to Ladinian - Carnian of the international reference scale, and is generally called Lower Gipskeuper. The Germanic Triassic was deposited in the epicontinental (cratonic) central Europe Basin. It covered the area in between Great Britain, North Sea, Poland and Southern Germany. It is composed of cyclic deposits of multicolored mudstones, gypsum/anhydrite, and dolomite beds. The two cases of marine ingression - influenced sequences share some common features.

  4. Towards a user's guide to scenarios - a report on scenario types and scenario techniques

    Energy Technology Data Exchange (ETDEWEB)

    Boerjeson, Lena; Hoejer, Mattias; Dreborg, Karl-Henrik; Finnveden, Goeran [Royal Inst. of Technology, Stockholm (Sweden). Environmental Strategies Research - fms; Ekvall, Tomas [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Energy and Environment

    2005-11-01

    Futures studies consist of a vast variation of studies and approaches. The aim of this paper is to contribute to the understanding of for what purposes scenarios are useful and what methods and procedures are useful for furthering these purposes. We present a scenario typology with an aim to better suit the context in which the scenarios are used. The scenario typology is combined with a new way of looking at scenario techniques, i.e. practical methods and procedures for scenario development. Finally, we look at the usefulness of scenarios in the light of the scenario typology and the scenario techniques. As a start, we distinguish between three main categories of scenario studies. The classification is based on the principal questions we believe a user may want to pose about the future. The resolution is then increased by letting each category contain two different scenario types. These are distinguished by different angles of approach of the questions defining the categories. The first question, What will happen?, is responded to by Predictive scenarios. In fact, the response to a question like this will always be conditional, e.g. of a stable and peaceful world, or by a certain continuous development of some kind. We have utilized this fact when defining the two predictive scenario types, Forecasts and What-if scenarios. The second question, What can happen?, is responded to by Explorative scenarios. The scenarios are thus explorations of what might happen in the future, regardless of beliefs of what is likely to happen or opinions of what is desirable. This category is further divided into external and strategic scenarios. The final question, How can a specific target be reached?, is responded to by Normative scenarios. Such studies are explicitly normative, since they take a target as a starting point. They are often directed towards how the target could be reached. This category is divided into preserving and transforming scenarios. If the user wants to

  5. Safety aspects of tritium storage in metal hydride form

    International Nuclear Information System (INIS)

    Air or nitrogen ingress accident scenarios into JET tritium storage containers, filled with uranium or intermetallic compound (IMC) hydrides, are discussed based on the experimentally determined kinetics of the reaction of these hydrides with air, O2 and N2. Reaction of uranium with air can occur at room temperature. For the initiation of the reactions of uranium with N2 or of some intermetallic compounds with air, elevated temperatures are required. Temperature rises of the metal hydrides due to air ingress are estimated for various cases. Modern tritium storage containers are protected against air ingress by intermediate and secondary containments which can be either evacuated or filled with inert gas. Therefore, air ingress can only occur due to double failure: failure of secondary containment and process containment at the same time. At JET, the secondary containments are filled with N2. However, even for N2, temperature increases are expected during the ingress into uranium beds (U-beds) for particular scenarios. It is shown that the JET design would not fail in this event. The calculation also shows that the smallest temperature rises during air, O2 or N2 ingress are expected for a getter bed design with free space above the metal getter layer for the gas to flow from inlet to outlet tube. 14 refs., 3 figs., 4 tabs

  6. Danish greenhouse gas reduction scenarios for 2020 and 2050

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, K.; Joergensen, Kaj. (Risoe DTU, Roskilde (DK)); Werling, J.; OErsted Pedersen, H.; Kofoed-Wiuff, A. (Ea energy Analysis, Copenhagen (DK))

    2008-02-15

    The aim of the project presented in this report was to develop scenarios for reducing Danish greenhouse gas emissions in 2020 and 2050. The scenarius provide a basis for estimating which technologies should be combined in order to obtain future reductions in greenhouse gas emissions in a cost-effective way. The scenarios include all emissions of greenhouse gases from agriculture, industry and oil extraction activities in the North Sea as well as the transport and energy sectors. Foreign air and sea carriage is not included because emissions related to such activities are not yet subject to international climate change agreements. The scenarios focus particularly on the technological possibilities and the necessary system changes in the Danish energy system and transport sector. Parallel to this, COWI has carried out analyses for the Danish Environmental Protection Agency focussing primarily on the reduction potentials in the transport sector and other emissions. COWI's results regarding agriculture and other emissions have been included in this analysis. Two timeframes are applied in the scenarios: the medium term, 2020, and the long term, 2050. For each timeframe, we have set up indicative targets that the scenarios must reach: 1) 2020: 30 and 40 % reduction in greenhouse gas emissions compared to 1990 2) 2050: 60 and 80 % reduction in greenhouse gas emissions compared to 1990. The scenarios for 2020 focus primarily on technologies that are already commercially available, whereas the scenarios for 2050 also examine technological options at the experimental or developmental stage. This includes hydrogen technologies and fuel cells as well as CO{sub 2} capture and sequestration (CCS) technologies. The scenarios should be seen in connection with the EU objectives of a 20-30 % reduction in greenhouse gas emissions in 2020 and 60-80 % in 2050 compared to 1990. The EU's 30 % objective is contingent upon global efforts to reduce the world's greenhouse gas

  7. Multiple scenarios of bentonite alteration

    International Nuclear Information System (INIS)

    Performance assessment for TRU waste repositories has shown that soluble and poorly sorbing nuclides such as I-129 and C-14 dominate the dose. These nuclides are expected to migrate with groundwater flow, hence hydraulic conditions and their evolution with time in the repository are key issues for repository safety. Cementitious material will be used for waste packaging, backfilling and structural material in a TRU waste repository. Bentonite is also expected to be used for some TRU wastes to provide the function of a hydraulic barrier in the disposal system. There is concern that the coexistence of cementitious material and bentonite cause the alteration of smectite due to interaction with hyperalkaline leachates and consequent deleterious perturbation of the function of bentonite as a hydraulic barrier. Many research studies have been performed to identify possible mechanisms of cement-bentonite interaction. However, uncertainties still exist in our understanding of the precise chemical scheme of bentonite alteration in highly alkaline conditions, especially the space and time variation of secondary mineral occurrences. In order to reflect this uncertainty, multiple scenarios of bentonite alteration were developed based on the possible mineralogical changes derived from knowledge of both experiments and observation of natural systems. It was focused that the mineral reaction involving hyperalkaline fluids would thermodynamically depend on the variable chemical condition in bentonite buffer and that kinetics would be important as well as thermodynamic stability in controlling their occurrence, i.e., the kinetic controls may operate to remain metastable minerals over the long term. The mineralogical consequences of the interaction between clays and alkaline fluids are summarized as follows. Clay → C-S-H gel and other solids which can rapidly precipitate. Clay and gel → illite. Clay and gel → metastable zeolite. Clay and gel → metastable zeolite → stable

  8. Web Based Tool for Mission Operations Scenarios

    Science.gov (United States)

    Boyles, Carole A.; Bindschadler, Duane L.

    2008-01-01

    A conventional practice for spaceflight projects is to document scenarios in a monolithic Operations Concept document. Such documents can be hundreds of pages long and may require laborious updates. Software development practice utilizes scenarios in the form of smaller, individual use cases, which are often structured and managed using UML. We have developed a process and a web-based scenario tool that utilizes a similar philosophy of smaller, more compact scenarios (but avoids the formality of UML). The need for a scenario process and tool became apparent during the authors' work on a large astrophysics mission. It was noted that every phase of the Mission (e.g., formulation, design, verification and validation, and operations) looked back to scenarios to assess completeness of requirements and design. It was also noted that terminology needed to be clarified and structured to assure communication across all levels of the project. Attempts to manage, communicate, and evolve scenarios at all levels of a project using conventional tools (e.g., Excel) and methods (Scenario Working Group meetings) were not effective given limitations on budget and staffing. The objective of this paper is to document the scenario process and tool created to offer projects a low-cost capability to create, communicate, manage, and evolve scenarios throughout project development. The process and tool have the further benefit of allowing the association of requirements with particular scenarios, establishing and viewing relationships between higher- and lower-level scenarios, and the ability to place all scenarios in a shared context. The resulting structured set of scenarios is widely visible (using a web browser), easily updated, and can be searched according to various criteria including the level (e.g., Project, System, and Team) and Mission Phase. Scenarios are maintained in a web-accessible environment that provides a structured set of scenario fields and allows for maximum

  9. Synopsis of global scenario and forecasting surveys scenarios in risk habitat megacity (RHM)

    OpenAIRE

    Woll, Tobias

    2008-01-01

    The main objective of the paper is to provide a synopsis of global scenario and forecasting surveys. First, the paper will give an overview on existing global scenario and forecasting surveys and their specific scenario philosophies and storylines. Second, the major driving forces that shape and characterise the different scenarios will be identified. The scenario analysis has been provided for the research project Risk Habitat Megacity (HRM) that aims at developing strategies for sustain...

  10. Innovations in science and scenarios for assessment

    Energy Technology Data Exchange (ETDEWEB)

    Kunkel, Kenneth E.; Moss, Richard H.; Parris, Adam

    2016-02-01

    Scenarios for the Third National Climate Assessment (NCA3) were produced for physical climate and sea level rise with substantial input from disciplinary and regional experts. These scenarios underwent extensive review and were published as NOAA Technical Reports. For land use/cover and socioeconomic conditions, scenarios already developed by other agencies were specified for use in the NCA3. Efforts to enhance participatory scenario planning as an assessment activity were pursued, but with limited success. Issues and challenges included the timing of availability of scenarios, the need for guidance in use of scenarios, the need for approaches to nest information within multiple scales and sectors, engagement and collaboration of end users in scenario development, and development of integrated scenarios. Future assessments would benefit from an earlier start to scenarios development, the provision of training in addition to guidance documents, new and flexible approaches for nesting information, ongoing engagement and advice from both scientific and end user communities, and the development of consistent and integrated scenarios.

  11. Project scenarios for bitumen upgrading

    International Nuclear Information System (INIS)

    The established reserves of Alberta's heavy oil resources are 178 billion barrels, and potential recoverable reserves are 315 billion barrels. The challenge of production includes the logistics of recovery, upgrading and transportation to market. Utilization of the bitumen is not simple because bitumen is too viscous to transport by pipeline. In addition, it is not processable by most existing refineries unless it can be upgraded through dilution. This paper examined different factors regarding the economic viability of various upgrading methods of a wide range of bitumen feedstocks. The study also examined the sensitivity of refinery demand to the prices of these feedstocks, along with the competitiveness among bitumen-based feedstock and conventional crudes. Western Canada, Ontario and the PADD II district in the United States are the 3 major markets for western Canadian bitumen based feedstock, the demand for which depends on refinery configurations and asphalt demand. This paper described the following 4 generic scenarios that describe Alberta bitumen upgrading projects: (1) adjacent to open pit mines, (2) adjacent to steam assisted gravity drainage (SAGD) facilities, (3) remotely located from resource production at an existing refinery, and (4) pipeline bitumen. It was noted that producers should determine the best way to upgrade the bitumen to ensure there is an economic market for the product, but they should also be aware not to over process the bitumen so as not to leave existing refinery facilities under-utilized. 2 refs., 1 tab., 3 figs

  12. Scenario research: The food industry in 2010

    DEFF Research Database (Denmark)

    Stacey, Julia; Sonne, Anne-Mette; Jensen, Birger Boutrup

    2001-01-01

    MAPP and the Department of Manufacturing Engineering and Management, The Technical University of Denmark have constructed three scenarios about the Danish food industry in 2010. The aim has been to identify the demands the food industry can expect to meet in the future plus which research areas the...... public research should prioritise in order to support the development of competences within the food industry. The scenarios are isolated developments. In practise, the future is likely to be a combination of the different tendencies within the scenarios. The first scenario 'Naturalness' has focus on...... practicians in relation to the scenarios. The scenario 'Naturalness' requires a change of attitude among food producers and society in general. A big challenge for the Danish food industry is that they must accept that its primary role will change from being an important exporting industry to an industry...

  13. Scenarios for the assessment of urban exposures after radioactive contamination

    International Nuclear Information System (INIS)

    Accidents involving radioactive material are not frequent but may include releases of radionuclides to the air, land or waterways. These releases are usually uncontrollable and may lead to doses in the public in excess of the reference levels established by regulations defined by the national regulatory agencies of each country. Although they had occurred sporadically since the last century, it was observed that, after the emergency phase, the public concern is enhanced when they feel that there is an unpreparedness of authorities responsible for remediation actions, due to the lack of definition of strategies to be adopted in the long term after such events. The aim of this work is to describe reference urban scenarios, considering the characteristics observed in residential and free access areas of urban centers. These scenarios were developed based on the counties surrounding the Brazilian nuclear power plant. Considering the counties within 50 km from the nuclear power plant, nine belong to the state of Rio de Janeiro and seven belong to São Paulo state; the highest population densities were observed in five counties of Rio de Janeiro. Based on the different types of residences and outdoor areas observed in these 16 counties, six reference scenarios for urban areas were developed including areas comprised by four types of residential houses (with low, medium and high shielding building material and houses in a row), apartments in buildings, and park areas with lawn and trees. The characteristics of each of these scenarios were raised through Google Earth images considering 1 km2 of different locations comprised by each type of area defined. In a next step, the information obtained in each scenario shall be used in computer simulations to characterize the effects and consequences on public exposure of the application of decontamination procedures. (authors)

  14. Electric Vehicle Scenarios for India: Implications for mitigation and development

    DEFF Research Database (Denmark)

    Shukla, P.R.; Dhar, Subash; Bhaskar, Kalyan

    2014-01-01

    electricity sector, CO2 mitigation and reduction in local air pollution. The Indian government has recently launched a national electricity mobility mission to promote EVs. There is, however, much uncertainty in terms of the penetration of EVs in the transport sector, particularly those related to...... infrastructure and policies. While the literature on EVs has focused more on the role of electric cars, it could be electric two-wheelers which could make early headway, as is the case in China where nearly 120 million such vehicles had been sold by the end of 2012. Three scenarios (Business as Usual (BAU...

  15. Scenario planning for the Edinburgh city region

    OpenAIRE

    Docherty, I.W.; McKiernan, P

    2008-01-01

    This paper examines the application of scenario planning techniques to the detailed and daunting challenge of city re-positioning when policy makers are faced with a heavy history and a complex future context. It reviews a process of scenario planning undertaken in the Edinburgh city region, exploring the scenario process and its contribution to strategies and policies for city repositioning. Strongly rooted in the recent literature on urban and regional economic development, the text outline...

  16. Renormalization-group improved inflationary scenarios

    CERN Document Server

    Pozdeeva, E O

    2016-01-01

    The possibility to construct an inflationary scenario for renormalization-group improved potentials corresponding to the Higgs sector of quantum field models is investigated. Taking into account quantum corrections to the renormalization-group potential which sums all leading logs of perturbation theory is essential for a successful realization of the inflationary scenario, with very reasonable parameters values. The scalar electrodynamics inflationary scenario thus obtained are seen to be in good agreement with the most recent observational data.

  17. Assessing supervisory scenarios for interest rate risk

    OpenAIRE

    Lopez, Jose A.; Christensen, Jens H.E.

    2015-01-01

    A new proposal by the Basel Committee on Banking Supervision for setting the amount of capital banks must hold against potential losses from interest rate risk uses only a few, very stylized scenarios. Analysis shows the proposed scenarios are extremely unlikely to occur. While they may be appropriate for setting bank capital guidelines, they are much less relevant for everyday risk management. Instead, using a modeling framework with a plausible range of interest rate scenarios would be more...

  18. Transportation accident scenarios for commercial spent fuel

    International Nuclear Information System (INIS)

    A spectrum of high severity, low probability, transportation accident scenarios involving commercial spent fuel is presented together with mechanisms, pathways and quantities of material that might be released from spent fuel to the environment. These scenarios are based on conclusions from a workshop, conducted in May 1980 to discuss transportation accident scenarios, in which a group of experts reviewed and critiqued available literature relating to spent fuel behavior and cask response in accidents

  19. Scenario-based Training: Director's Cut

    OpenAIRE

    Peeters, M.M.M.; van den Bosch, K.; Meyer, J-J.Ch.; Neerincx, M. A.

    2011-01-01

    Research regarding autonomous learning shows that freeplay does not result in optimal learning. Combining scenario-based training with intelligent agent technology off ers the possibility to create autonomous training enriched with automated adaptive support delivered by a director agent. We conducted an experiment to investigate whether directing training scenarios improves the quality of training. Six instructors rated video fragments of directed and non-directed scenarios in terms of learn...

  20. Spatially comprehensive data for forestry scenario analysis

    OpenAIRE

    Barth, Andreas

    2007-01-01

    This thesis focuses on the use of forest data for national level policy making. Three major issues were considered: (i) to determine typical requirements of data in forestry scenario analysis, (ii) to evaluate and further develop methods to determine data requirements, and (iii) to develop methods that improve data usability in forestry scenario analysis. Increasingly, the trend is to use spatially comprehensive data as a basis for forestry scenario analysis. Compared to traditional approache...

  1. Modeling of Demining Scenarios Using Metal Detectors

    OpenAIRE

    John Fernando Vargas Buitrago; Roberto Bustamante Miller; Everett, Mark E.

    2014-01-01

    This paper presents an analytical model and a numerical model that uses the finite element method to simulate demining scenarios using metal detectors. Using the analytical model, simulations of typical demining scenarios with varying parameters were executed. In addition, an analysis was made that aids in clearly understanding the effect of the scenario variables on a Continuous Wave metal detector response. In order to experimentally validate the numerical model, a Continuous Wave metal det...

  2. Analysis of the energy scenario Negawatt 2006

    International Nuclear Information System (INIS)

    The association Negawatt published in 2003 an energy scenario for the France in 2050, under the name of Negawatt 2006. This document aims to analyze the scenario Negawatt with a comparison of the scenario published on the web site of SLC, Save the Climate. The authors analyzes the main three sectors: electricity, transports and residential to propose their comparison in conclusion. (A.L.B.)

  3. Transportation accident scenarios for commercial spent fuel

    Energy Technology Data Exchange (ETDEWEB)

    Wilmot, E L

    1981-02-01

    A spectrum of high severity, low probability, transportation accident scenarios involving commercial spent fuel is presented together with mechanisms, pathways and quantities of material that might be released from spent fuel to the environment. These scenarios are based on conclusions from a workshop, conducted in May 1980 to discuss transportation accident scenarios, in which a group of experts reviewed and critiqued available literature relating to spent fuel behavior and cask response in accidents.

  4. COMPETITIVE INTELLIGENCE ANALYSIS - SCENARIOS METHOD

    Directory of Open Access Journals (Sweden)

    Ivan Valeriu

    2014-07-01

    Full Text Available Keeping a company in the top performing players in the relevant market depends not only on its ability to develop continually, sustainably and balanced, to the standards set by the customer and competition, but also on the ability to protect its strategic information and to know in advance the strategic information of the competition. In addition, given that economic markets, regardless of their profile, enable interconnection not only among domestic companies, but also between domestic companies and foreign companies, the issue of economic competition moves from the national economies to the field of interest of regional and international economic organizations. The stakes for each economic player is to keep ahead of the competition and to be always prepared to face market challenges. Therefore, it needs to know as early as possible, how to react to others’ strategy in terms of research, production and sales. If a competitor is planning to produce more and cheaper, then it must be prepared to counteract quickly this movement. Competitive intelligence helps to evaluate the capabilities of competitors in the market, legally and ethically, and to develop response strategies. One of the main goals of the competitive intelligence is to acknowledge the role of early warning and prevention of surprises that could have a major impact on the market share, reputation, turnover and profitability in the medium and long term of a company. This paper presents some aspects of competitive intelligence, mainly in terms of information analysis and intelligence generation. Presentation is theoretical and addresses a structured method of information analysis - scenarios method – in a version that combines several types of analysis in order to reveal some interconnecting aspects of the factors governing the activity of a company.

  5. From Scenarios to Test Implementations Via Promela

    Science.gov (United States)

    Ulrich, Andreas; Alikacem, El-Hachemi; Hallal, Hesham H.; Boroday, Sergiy

    We report on a tool for generating executable concurrent tests from scenarios specified as message sequence charts. The proposed approach features three steps: 1) Deriving a MSC test implementation from a MSC scenario, 2) Mapping the test implementation into a Promela model, 3) Generating executable test scripts in Java. The generation of an intermediate Promela model allows for model-checking to inspect the test implementation for properties like soundness, fault detection power as well as for consistency checking between different test scenarios. Moreover decoupling the executable test scripts from the scenario specification makes it possible to use different backend code generators to support other scripting languages when needed.

  6. Action research Toolkit II: The Scenario Workshop

    DEFF Research Database (Denmark)

    Rasmussen, Lauge Baungaard

    2003-01-01

    The article describes the scenario workshop within the action research paradigm. In addtion, the maina phases and the functions of the facilitator and the participants are outlined. Finally,it describes and analyses the experiences of using the scenario workshop in practice.......The article describes the scenario workshop within the action research paradigm. In addtion, the maina phases and the functions of the facilitator and the participants are outlined. Finally,it describes and analyses the experiences of using the scenario workshop in practice....

  7. Modeling of Demining Scenarios Using Metal Detectors

    Directory of Open Access Journals (Sweden)

    John Fernando Vargas Buitrago

    2014-08-01

    Full Text Available This paper presents an analytical model and a numerical model that uses the finite element method to simulate demining scenarios using metal detectors. Using the analytical model, simulations of typical demining scenarios with varying parameters were executed. In addition, an analysis was made that aids in clearly understanding the effect of the scenario variables on a Continuous Wave metal detector response. In order to experimentally validate the numerical model, a Continuous Wave metal detector prototype was built to obtain experimental data. The numerical method can also be used to simulate demining scenarios with high metallic content landmines.

  8. Evaluation of indoor air composition time variation in air-tight occupied spaces during night periods

    Science.gov (United States)

    Markov, Detelin

    2012-11-01

    This paper presents an easy-to-understand procedure for prediction of indoor air composition time variation in air-tight occupied spaces during the night periods. The mathematical model is based on the assumptions for homogeneity and perfect mixing of the indoor air, the ideal gas model for non-reacting gas mixtures, mass conservation equations for the entire system and for each species, a model for prediction of basal metabolic rate of humans as well as a model for prediction of O2 consumption rate and both CO2 and H2O generation rates by breathing. Time variation of indoor air composition is predicted at constant indoor air temperature for three scenarios based on the analytical solution of the mathematical model. The results achieved reveal both the most probable scenario for indoor air time variation in air-tight occupied spaces as well as the cause for morning tiredness after having a sleep in a modern energy efficient space.

  9. Air quality and communication. Special issue

    International Nuclear Information System (INIS)

    In six articles Attention is paid to mainly the practical appliances of communication in relation to the aspects of air quality: the perceptions of air pollution of those people who are affected by it; the tuning of information on air quality to the wishes and needs of citizens; tools enabling visualisation of future situations in the living environment in various scenarios; results of a study of the need for information on air quality among citizens and general practitioners; experiences with websites on air quality obtained in two European projects. (mk)

  10. Air Pollution and Control Legislation in India

    Science.gov (United States)

    P Bhave, Prashant; Kulkarni, Nikhil

    2015-09-01

    Air pollution in urban areas arises from multiple sources, which may vary with location and developmental activities. Anthropogenic activities as rampant industrialization, exploitation and over consumption of natural resources, ever growing population size are major contributors of air pollution. The presented review is an effort to discuss various aspects of air pollution and control legislation in India emphasizing on the history, present scenario, international treaties, gaps and drawbacks. The review also presents legislative controls with judicial response to certain landmark judgments related to air pollution. The down sides related to enforcement mechanism for the effective implementation of environmental laws for air pollution control have been highlighted.

  11. TURVA-2012: Formulation of radionuclide release scenarios

    International Nuclear Information System (INIS)

    TURVA-2012 is Posiva's safety case in support of the Preliminary Safety Analysis Report (PSAR) and application for a construction licence for a repository for disposal of spent nuclear fuel at the Olkiluoto site in south-western Finland. This paper gives a summary of the scenarios and the methodology followed in formulating them as described in TURVA-2012: Formulation of Radionuclide Release Scenarios (Posiva, 2013). The scenarios are further analysed in TURVA-2012: Assessment of Radionuclide Release Scenarios for the Repository System and TURVA-2012: Biosphere Assessment (Posiva, 2012a, 2012b). The formulation of scenarios takes into account the safety functions of the main barriers of the repository system and the uncertainties in the features, events, and processes (FEP) that may affect the entire disposal system (i.e. repository system plus the surface environment) from the emplacement of the first canister until the far future. In the report TURVA-2012: Performance Assessment (2012d), the performance of the engineered and natural barriers has been assessed against the loads expected during the evolution of the repository system and the site. Uncertainties have been identified and these are taken into account in the formulation of radionuclide release scenarios. The uncertainties in the FEP and evolution of the surface environment are taken into account in formulating the surface environment scenarios used ultimately in estimating radiation exposure. Formulating radionuclide release scenarios for the repository system links the reports Performance Assessment and Assessment of Radionuclide Release Scenarios for the Repository System. The formulation of radionuclide release scenarios for the surface environment brings together biosphere description and the surface environment FEP and is the link to the assessment of the surface environment scenarios summarised in TURVA-2012: Biosphere Assessment. (authors)

  12. Uncertainty in Integrated Assessment Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Mort Webster

    2005-10-17

    trends from a model for uncertainty projections. The probability distributions of these critical model drivers, and the resulting uncertainty in projections from a range of models, can provide the basis of future emission scenario set designs.

  13. Analysis of air permeability and WVTR characteristics of highly impermeable novel rubber nanocomposite

    International Nuclear Information System (INIS)

    This work focuses on analyzing the barrier properties of novel Bromobutyl (BIIR)- Polyepichlorohydrin (CO) rubber nanocomposites and developing a unique model to ease the understanding of the water vapor transmission rate (WVTR) properties. Air permeability, WVTR and morphology of BIIR-CO nanocomposites were investigated and compared with the standard BIIR vulcanizate. From the morphological studies using AFM imaging technique and HR-TEM measurements, the developed BIIR-CO nanocomposites were considered to have a mostly intercalated structure. However, the dispersion of the nanoclay in the composites was very good. Air permeability of BIIR-CO nanocomposites decreased dramatically by 64% as compared to that of the standard BIIR vulcanizate. Considerable reduction in WVTR up to 25% was also achieved for BIIR-CO nanocomposites. Attempts were made to fit the experimental data of the relative gas permeability of nanocomposites with various models predicted earlier. It was observed that the nanoclay orientation ranged from perfect to random, which was decisive in improving the gas barrier properties. A basic model has been developed to predict the water vapor ingress by considering the polarity factor along with tortuosity factor which has been presented schematically. It reiterates the dependency of water vapor ingress on the polarity of the BIIR-CO rubber nanocomposites. (paper)

  14. A methodology for developing Distributed Generation scenarios in urban areas using geographical information systems

    OpenAIRE

    Medrano Martorell, Marc; Brouwer, Jack; Carreras-Sospedra, Marc; Rodriguez, Marco A.; Dabdub, Donald; Samuelsen, G. Scott

    2008-01-01

    The implementation of Distributed Generation (DG) may lead to increased pollutant emissions that adversely affect air quality. This work presents a systematic methodology to characterise DG installation in urban basins. First, a set of parameters that characterise a DG implementation scenario is described. Second, a general approach using Geographic Information Systems (GIS) data is presented. Third, the methodology is demonstrated by application to the South Coast Air Basin...

  15. Architectures for Developing Multiuser, Immersive Learning Scenarios

    Science.gov (United States)

    Nadolski, Rob J.; Hummel, Hans G. K.; Slootmaker, Aad; van der Vegt, Wim

    2012-01-01

    Multiuser immersive learning scenarios hold strong potential for lifelong learning as they can support the acquisition of higher order skills in an effective, efficient, and attractive way. Existing virtual worlds, game development platforms, and game engines only partly cater for the proliferation of such learning scenarios as they are often…

  16. Elaborating SRES scenarios for nuclear energy

    International Nuclear Information System (INIS)

    The objective of this paper is identifying mid-century economic targets for nuclear energy. The first step is to describe what the mid-century energy market might look like: the major competitors for nuclear energy, what products are in demand, how much of each, where is growth greatest, and so forth. The mechanism for systematically describing the future market is scenario building. The starting point is the scenarios in the Special Report on Emissions Scenarios (SRES) of the Intergovernmental Panel on Climate Change. SRES developed four narrative story lines, each representing a different coherent set of demographic, social, economic, technological, and environmental developments. For each story line several different scenarios were developed by six international modelling teams, resulting in 40 scenarios grouped in the 4 story lines. For three of the story lines this paper uses a single marker scenario representative of central tendencies within the scenario family. For the fourth story line the authors chose the scenario that assumes that advances in non-fossil technologies - renewable, nuclear, and high-efficiency conservation technologies - make them most cost-competitive. (BA)

  17. Evaluation Framework for Dependable Mobile Learning Scenarios

    Science.gov (United States)

    Bensassi, Manel; Laroussi, Mona

    2014-01-01

    The goal of the dependability analysis is to predict inconsistencies and to reveal ambiguities and incompleteness in the designed learning scenario. Evaluation, in traditional learning design, is generally planned after the execution of the scenario. In mobile learning, this stage becomes too difficult and expensive to apply due to the complexity…

  18. Molecular Diagnostic Analysis of Outbreak Scenarios

    Science.gov (United States)

    Morsink, M. C.; Dekter, H. E.; Dirks-Mulder, A.; van Leeuwen, W. B.

    2012-01-01

    In the current laboratory assignment, technical aspects of the polymerase chain reaction (PCR) are integrated in the context of six different bacterial outbreak scenarios. The "Enterobacterial Repetitive Intergenic Consensus Sequence" (ERIC) PCR was used to analyze different outbreak scenarios. First, groups of 2-4 students determined optimal…

  19. Comparison of future energy scenarios for Denmark

    DEFF Research Database (Denmark)

    Kwon, Pil Seok; Østergaard, Poul Alberg

    2012-01-01

    Scenario-making is becoming an important tool in energy policy making and energy systems analyses. This article probes into the making of scenarios for Denmark by presenting a comparison of three future scenarios which narrate 100% renewable energy system for Denmark in 2050; IDA 2050, Climate...... Commission 2050, and CEESA (Coherent Energy and Environmental System Analysis). Generally, although with minor differences, the scenarios suggest the same technological solutions for the future such as expansion of biomass usage and wind power capacity, integration of transport sector into the other energy...... sectors. The methodologies used in two academic scenarios, IDA 2050 and CEESA, are compared. The main differences in the methodologies of IDA 2050 and CEESA are found in the estimation of future biomass potential, transport demand assessment, and a trial to examine future power grid in an electrical...

  20. Writing clinical scenarios for clinical science questions.

    Science.gov (United States)

    Smith, Phil Em; Mucklow, John C

    2016-04-01

    Written knowledge assessments for physicians in training typically involve multiple-choice questions that use a clinical scenario in a single-best-answer format. The Royal College of Physicians Part 1 MRCP(UK) examination includes basic sciences themes that are challenging to assess through a clinical scenario. A realistic clinical setting based on everyday clinical practice and integral to the question is the clearest demonstration that the knowledge being assessed is clinically relevant. However, without special attention to detail, the scenario in a clinical science question can appear redundant or artificial. Reading unnecessary material frustrates candidates and threatens the reputation of the assessment. In this paper we discuss why a clinical scenario is important for basic science questions and offer advice on setting realistic and plausible clinical scenarios for such questions. PMID:27037383

  1. The Greenpeace 2013 scenario for energy transition

    International Nuclear Information System (INIS)

    After a synthesis of the Greenpeace scenario for energy transition, this report presents the French current energy landscape: structure of the energy system, greenhouse gas emissions and nuclear risks, main social and economic challenges, and search for a political ambition (from the Grenelle de l'Environnement to the current debate on energy). Then, after having outlined that energy transition must be decided now, the report presents the scenario hypotheses: studies used to develop the scenario, macro-economic and technical-economic hypotheses. The scenario is then presented in terms of possible trajectory, of energy demand (global evolution per sector), of energy production (electricity, heat, mobility), and of CO2 assessment and nuclear wastes. Scenarios are compared in social and economic terms, more particularly in terms of investments in electricity and heat production systems, of electricity production costs and electricity bill, of energy independence, and of jobs in the electricity and heat sectors

  2. Tank waste remediation system operational scenario

    International Nuclear Information System (INIS)

    The Tank Waste Remediation System (TWRS) mission is to store, treat, and immobilize highly radioactive Hanford waste (current and future tank waste and the strontium and cesium capsules) in an environmentally sound, safe, and cost-effective manner (DOE 1993). This operational scenario is a description of the facilities that are necessary to remediate the Hanford Site tank wastes. The TWRS Program is developing technologies, conducting engineering analyses, and preparing for design and construction of facilities necessary to remediate the Hanford Site tank wastes. An Environmental Impact Statement (EIS) is being prepared to evaluate proposed actions of the TWRS. This operational scenario is only one of many plausible scenarios that would result from the completion of TWRS technology development, engineering analyses, design and construction activities and the TWRS EIS. This operational scenario will be updated as the development of the TWRS proceeds and will be used as a benchmark by which to evaluate alternative scenarios

  3. Accident scenario diagnostics with neural networks

    International Nuclear Information System (INIS)

    Nuclear power plants are very complex systems. The diagnoses of transients or accident conditions is very difficult because a large amount of information, which is often noisy, or intermittent, or even incomplete, need to be processed in real time. To demonstrate their potential application to nuclear power plants, neural networks axe used to monitor the accident scenarios simulated by the training simulator of TVA's Watts Bar Nuclear Power Plant. A self-organization network is used to compress original data to reduce the total number of training patterns. Different accident scenarios are closely related to different key parameters which distinguish one accident scenario from another. Therefore, the accident scenarios can be monitored by a set of small size neural networks, called modular networks, each one of which monitors only one assigned accident scenario, to obtain fast training and recall. Sensitivity analysis is applied to select proper input variables for modular networks

  4. An "acceptable" low carbon scenario for France: Participatory scenario design and economic assessment

    OpenAIRE

    Bibas, Ruben; Mathy, Sandrine; Fink, Meike

    2012-01-01

    The implementation of climate policies is often hindered by a lack of acceptability as well as the lack of long-term vision of stakeholders. Mitigation scenarios exercises allow the debate; however the scenario design process lacks transparency and stakeholders' (and citizens') involvement, which leads to a lack of credibility, legitimacy and ownership of mitigation scenarios. This paper presents a process for the collaborative design of an "acceptable" mitigation scenario through a public di...

  5. Scenario development for reaching urban and environmental planning integration in the context of climate change

    NARCIS (Netherlands)

    Zagare, V.M.E.; Sepulveda Carmona, D.A.

    2014-01-01

    Presentation based on a research done by appointment of Lincoln Institute of Land Policy, Cambridge, MA, USA. Nov 2013. Scenarios for an integral approach to urban and environmental dimensions in the Lower Parana Delta (Argentina). Consortia UBA-SU Buenos Aires-TUD

  6. Metaphorical scenarios in business science discourse

    Directory of Open Access Journals (Sweden)

    Baramee Kheovichai

    2015-04-01

    Full Text Available Metaphor has been shown to play an important role in business science discourse. Yet, previous corpus-based studies only investigated a pre-selected list of metaphoric expressions, potentially rendering the analysis incomplete. Furthermore, some studies which only focused on lexis did not analyse how the lexical items may construct business concepts in terms of scenarios. The purpose of this research is to investigate metaphor used to construct business concepts in business research articles. 42 business research articles published in 2009-2010 from five journals ranked in the top-ten according to the 2007 journal impact factors (Thompson Reuters, 2008 constitute the data of this study. Semantic annotation software USAS (Rayson, 2008 was used to assist in the retrieval of metaphoric expressions. Furthermore, manual analysis of concordances was done to find metaphorical expressions that had not been captured by the semantic tags. The analysis of these metaphoric expressions was based on Conceptual Metaphor Theory (Lakoff & Johnson, 1980 and Metaphor Scenario (Musolff, 2006. Data analysis indicates that metaphor constructs business concepts as scenarios which have participants performing actions to reach their goal according to the SOURCE-PATH-GOAL schema of the source domains. At the centre of these scenarios, the BOUNDED SPACE source domain serves as a conceptual space or a setting for each scenario. Other source domains, which are WAR, SPORT, GAME, JOURNEY, MACHINE, LIVING ORGANISM, BUILDING and PHYSICAL FORCES, project the scenarios onto the space, forming interconnected and coherent scenarios of business discourse

  7. Scenario Archetypes: Converging Rather than Diverging Themes

    Directory of Open Access Journals (Sweden)

    Jon P. Sadler

    2012-04-01

    Full Text Available Future scenarios provide challenging, plausible and relevant stories about how the future could unfold. Urban Futures (UF research has identified a substantial set (>450 of seemingly disparate scenarios published over the period 1997–2011 and within this research, a sub-set of >160 scenarios has been identified (and categorized based on their narratives according to the structure first proposed by the Global Scenario Group (GSG in 1997; three world types (Business as Usual, Barbarization, and Great Transitions and six scenarios, two for each world type (Policy Reform—PR, Market Forces—MF, Breakdown—B, Fortress World—FW, Eco-Communalism—EC and New Sustainability Paradigm—NSP. It is suggested that four of these scenario archetypes (MF, PR, NSP and FW are sufficiently distinct to facilitate active stakeholder engagement in futures thinking. Moreover they are accompanied by a well-established, internally consistent set of narratives that provide a deeper understanding of the key fundamental drivers (e.g., STEEP—Social, Technological, Economic, Environmental and Political that could bring about realistic world changes through a push or a pull effect. This is testament to the original concept of the GSG scenarios and their development and refinement over a 16 year period.

  8. Chemical aspects of hydrogen ingress in zirconium and zircaloy pressure tubes: ageing management of Indian PHWR coolant channels - determination of hydrogen and deuterium

    International Nuclear Information System (INIS)

    Pressurized heavy water reactors (PHWRs) use zirconium and zirconium based alloys as clad and coolant tubes since its beginning. The first ever zircaloy-2 pressure tube failure occurred in 1983 at Ontario Hydro's Pickering Unit 2 in Canada which necessitated a thorough examination of causes of such failure. The failure was attributed to massive hydriding at the failed spot of pressure tube. Continuous usage of zirconium alloys could result in their hydrogen and deuterium pick-up leading to hydrogen/ deuterium embrittlement. The life of the zircaloy coolant channels is dictated by hydrogen/deuterium content and hence ageing management of the pressure tubes is essential for ensuring their trouble-free usage. It is desirable to have a sound knowledge on the chemical aspects of zirconium and zirconium based alloys metallurgy, the mechanistic principles of hydrogen ingress into the pressure tubes during in reactor service, and identifying suitable analytical methodologies for precise and accurate determination of hydrogen in wafer thin sliver samples carved out from insides of pressure tubes without causing any structural damage so that it can continue to remain in service. This is desirable so that the ageing management does not result in cost-escalation. This report is divided in to three main parts. The first part deals with the chemical aspects of zirconium and zirconium based alloy metallurgy, the mechanism of hydrogen pick-up and hydride formation in zirconium matrix. The second part describes various methodologies and their limitations, available for hydrogen/deuterium determination. The third part deals in detail, about the extensive investigations carried out at Radioanalytical Chemistry Division (RACD) in Radiochemistry and Isotope Group for establishing an indigenously developed hot vacuum extraction system in combination with quadrupole mass spectrometry for precise determination of hydrogen and deuterium in wafer thin sliver sample of zircaloy. The

  9. Accelerated Option Pricing in Multiple Scenarios

    CERN Document Server

    Dirnstorfer, Stefan

    2008-01-01

    This paper covers a massive acceleration of Monte-Carlo based pricing method for financial products and financial derivatives. The method is applicable in risk management settings, where a financial product has to be priced under a number of potential future scenarios. Instead of starting a separate nested Monte Carlo simulation for each scenario under consideration, the new method covers the utilization of very few representative nested simulations and estimating the product prices at each scenario by a smoothing method based on the state-space. This smoothing technique can be e.g. non-parametric regression or kernel smoothing.

  10. Baseline scenarios of global environmental change

    International Nuclear Information System (INIS)

    This paper presents three baseline scenarios of no policy action computed by the IMAGE2 model. These scenarios cover a wide range of coupled global change indicators, including: energy demand and consumption; food demand, consumption, and production; changes in land cover including changes in extent of agricultural land and forest; emissions of greenhouse gases and ozone precursors; and climate change and its impacts on sea level rise, crop productivity and natural vegetation. Scenario information is available for the entire world with regional and grid scale detail, and covers from 1970 to 2100. (author)

  11. The energy consumption of traffic 1990 - 2035 - Results of scenarios I - IV

    International Nuclear Information System (INIS)

    This comprehensive report for the Swiss Federal Office of Energy (SFOE) presents four scenarios concerning the development of energy consumption in the traffic sector for the period 1990 - 2035. The four scenarios - status quo, increased co-operation between the state and the economy with various energy levies, global reduction of energy consumption and, finally, scenario IV 'on the way to a 2000-Watt Society' - are briefly described. The areas examined include road, rail and air traffic as well as 'off-road' traffic. Infrastructure developments are commented on. The four scenarios are examined for various sensitivities including high gross domestic product GDP, high prices and warmer climate. Alternative fuels are looked at, as are further factors such as fuel tourism, pollutant emissions and costs. The results of the sensitivity analyses are compared and discussed and the necessary instruments are examined. This comprehensive report is completed with a comprehensive appendix

  12. Energy prospects for the sector Transportation. Scenario IV

    International Nuclear Information System (INIS)

    In this study for the Swiss Federal Office of Energy, mathematical models are used to predict the energy consumption by the year 2030 of the whole transportation sector including air traffic for Switzerland. In the so-called Scenario IV considered here, stringent but still realistic assumptions are made regarding technologies, taxes and legislation while economic growth is retained as an essential background feature as in previous scenarios with less stringent measures. Fossil fuels still are the main energy source for road and air transportation, but drastic efficiency improvements reduce the specific fuel consumption: (i) with an average reduction of 3% a year, the specific consumption of cars falls from 9 litre/100 km in 1990 down to less than 3 litre/100 km in 2030; (ii) for lorries, it falls from 30 down to 22 litre/100 km in the same time period; (iii) the energy efficiency improvement up to 2030 is 45% for the air traffic, under the assumption of an internationally harmonised kerosene tax. In parallel, fuel market price increase, so that the energy expenses remain constant for most vehicles. For goods transportation by rail an efficiency improvement of 33% is assumed, so that a partial shift from the road to the rail takes place. For passengers transportation by rail, better comfort, more frequent trains and extended regional tariff agreements stimulate an increased usage of public transportation systems. Measures are also considered in the fields of urbanism (where to live and where to work) and traffic management (avoidance of empty courses for lorries). Altogether, the measures described lead to an annual final-energy consumption of 148 PJ in 2030 for Switzerland, compared to 251 PJ in 1990

  13. Model and scenario variations in predicted number of generations of Spodoptera litura Fab. on peanut during future climate change scenario.

    Directory of Open Access Journals (Sweden)

    Mathukumalli Srinivasa Rao

    Full Text Available The present study features the estimation of number of generations of tobacco caterpillar, Spodoptera litura. Fab. on peanut crop at six locations in India using MarkSim, which provides General Circulation Model (GCM of future data on daily maximum (T.max, minimum (T.min air temperatures from six models viz., BCCR-BCM2.0, CNRM-CM3, CSIRO-Mk3.5, ECHams5, INCM-CM3.0 and MIROC3.2 along with an ensemble of the six from three emission scenarios (A2, A1B and B1. This data was used to predict the future pest scenarios following the growing degree days approach in four different climate periods viz., Baseline-1975, Near future (NF -2020, Distant future (DF-2050 and Very Distant future (VDF-2080. It is predicted that more generations would occur during the three future climate periods with significant variation among scenarios and models. Among the seven models, 1-2 additional generations were predicted during DF and VDF due to higher future temperatures in CNRM-CM3, ECHams5 & CSIRO-Mk3.5 models. The temperature projections of these models indicated that the generation time would decrease by 18-22% over baseline. Analysis of variance (ANOVA was used to partition the variation in the predicted number of generations and generation time of S. litura on peanut during crop season. Geographical location explained 34% of the total variation in number of generations, followed by time period (26%, model (1.74% and scenario (0.74%. The remaining 14% of the variation was explained by interactions. Increased number of generations and reduction of generation time across the six peanut growing locations of India suggest that the incidence of S. litura may increase due to projected increase in temperatures in future climate change periods.

  14. Strategic Positioning in Tactical Scenario Planning

    CERN Document Server

    Whitacre, James M; Sarker, Ruhul; Bender, Axel; Baker, Stephen; 10.1145/1389095.1389293

    2009-01-01

    Capability planning problems are pervasive throughout many areas of human interest with prominent examples found in defense and security. Planning provides a unique context for optimization that has not been explored in great detail and involves a number of interesting challenges which are distinct from traditional optimization research. Planning problems demand solutions that can satisfy a number of competing objectives on multiple scales related to robustness, adaptiveness, risk, etc. The scenario method is a key approach for planning. Scenarios can be defined for long-term as well as short-term plans. This paper introduces computational scenario-based planning problems and proposes ways to accommodate strategic positioning within the tactical planning domain. We demonstrate the methodology in a resource planning problem that is solved with a multi-objective evolutionary algorithm. Our discussion and results highlight the fact that scenario-based planning is naturally framed within a multi-objective setting...

  15. Experts dismiss doomsday scenarios for RHIC

    CERN Multimedia

    Levi, B G

    2000-01-01

    A panel of particle physicists examining the possibility that operation of RHIC could generate blackholes or 'strangelets' which would consume ordinary matter, have declared that such scenarios are 'firmly excluded' (1 p).

  16. Peninsular Florida future scenarios integrated project

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a integrated scenario project to the Florida state line that incorporates updated critical land and water identification project layers with a decision...

  17. Environmental evaluation of plastic waste management scenarios

    DEFF Research Database (Denmark)

    Rigamonti, L.; Grosso, M.; Møller, Jacob;

    2014-01-01

    The management of the plastic fraction is one of the most debated issues in the discussion on integrated municipal solid waste systems. Both material and energy recovery can be performed on such a waste stream, and different separate collection schemes can be implemented. The aim of the paper...... is to contribute to the debate, based on the analysis of different plastic waste recovery routes. Five scenarios were defined and modelled with a life cycle assessment approach using the EASEWASTE model. In the baseline scenario (P0) the plastic is treated as residual waste and routed partly to incineration....... The study confirmed the difficulty to clearly identify an optimal strategy for plastic waste management. In fact none of the examined scenarios emerged univocally as the best option for all impact categories. When moving from the P0 treatment strategy to the other scenarios, substantial improvements can...

  18. ANCRE scenarios for energy transition. Report 2013

    International Nuclear Information System (INIS)

    This report first gives an overview of the energy system by presenting the determining factors of energy demand and of CO2 emissions per sector (housing and office building, transport, industry, agriculture, forestry and biomass), by analysing energy systems and CO2 emissions (energy sources, energy vectors, networks and storage, energy and CO2 assessment for France), and by describing the guidelines of the scenarios proposed by ANCRE. The three main scenarios are characterized by a stronger sobriety, an electricity-based de-carbonation (with a variant based on nuclear and renewable energies), and diversified vectors. They are notably compared to a trend-based reference scenario. Results are discussed in terms of energy consumption (primary and final energy, consumption by the different sectors), of energy production and CO2 emissions. Scenarios are assessed in terms of economic, environmental and societal, political and strategic criteria. Some consequences for research topics and funding are identified

  19. Scenarios for the food industry in 2010

    DEFF Research Database (Denmark)

    Harmsen, Hanne; Jensen, Birger Boutrup; Sonne, Anne-Mette

    2001-01-01

    Predicting the future is impossible; corporate decision-makers have, however, to decide which competencies to develop precisely on this basis. This article presents the results of a research project on scenario analyses in the Danish food industry. The aim of the study is to look at alternative...... visions of the future of the food industry and to assess their implications for competence requirements. Given the uncertain nature of the environment, food companies cannot rely on today's competencies being sufficient to fulfil the demands of tomorrow's markets. However, predicting the determinants of...... success in the food industry 10 years hence is a daunting task. Scenario techniques can be very useful in this respect (von Reibnitz, 1988). The contribution of the article is the methodological approach to scenario building, which combines academic and industry input and translates the scenarios into the...

  20. Development of Future Scenario Emission Inventories for East Asia in Support of Multiple Modeling Studies

    Science.gov (United States)

    Kim, Y.; Woo, J. H.; Choi, K. C.; Lee, J. B.; Song, C. K.; Kim, S. K.; Hong, J.; Hong, S. C.; Zhang, Q.; Hong, C.; Tong, D.

    2015-12-01

    Future emission scenarios based on up-to-date regional socio-economic and control policy information were developed in support of climate-air quality integrated modeling research over East Asia. Two IPCC-participated Integrated Assessment Models(IAMs) were used to developed those scenario pathways. The two emission processing systems, KU-EPS and SMOKE-Asia, were used to convert these future scenario emissions to comprehensive chemical transport model-ready form. The NIER/KU-CREATE (Comprehensive Regional Emissions inventory for Atmospheric Transport Experiment) served as the regional base-year emission inventory. For anthropogenic emissions, it has 54 fuel classes, 201 sub-sectors and 13 pollutants, including CO2, CH4, N2O, SO2, NOx, CO, NMVOC, NH3, OC, BC, PM10, PM2.5, and mercury. Fast energy growth and aggressive penetration of the control measures make emissions projection very active for East Asia. Despite of more stringent air pollution control policies by the governments, however, air quality over the region seems not been improved as much - even worse in many cases. The needs of more scientific understanding of inter-relationship among emissions, transport, chemistry over the region are very high to effectively protect public health and ecosystems against ozone, fine particles, and other toxic pollutants in the air. After developing these long-term future emissions, therefore, we also tried to apply our future scenarios to develop the present emissions inventory for chemical weather forecasting and aircraft field campaign. On site, we will present; 1) the future scenario development framework and process methodologies, 2) initial development results of the future emission pathways, 3) present emission inventories from short-term projection, and 4) air quality modeling performance improvements over the region.

  1. Air Pollution

    OpenAIRE

    Lawther, P. J.

    2014-01-01

    The human costs of air pollution are considerable in Jordan. According to a report published in 2000 by the World Bank under the Mediterranean Environmental Technical Assistance Program (METAP), approximately 600 people die prematurely each year in Jordan because of urban pollution. 50-90% of air pollution in Jordanian towns is caused by road traffic. Readings taken in 2007 by Jordanian researchers showed that levels of black carbon particles in the air were higher in urban areas (caused by v...

  2. Scenario research: The food industry in 2010

    OpenAIRE

    Stacey, Julia; Sonne, Anne-Mette; Jensen, Birger Boutrup

    2001-01-01

    What kind of foods will the consumers choose to buy in 2010? Will they be buying organic foods, functional foods or go for the cheapest products? Nobody can predict the future. However, by using scenario techniques qualified indications on future developments can be put together. Researchers at MAPP and the Department of Manufacturing Engineering and Management, The Technical University of Denmark have constructed three scenarios about the Danish food industry in 2010. The aim has been to ide...

  3. Eco-correlation in acidification scenarios

    OpenAIRE

    2001-01-01

    The bulk of acid depositions, which have harmful effects on the environment, are caused by foreign emissions in many European countries. Therefore, if some countries emit more acids, one cannot be sure that countries that emit less will benefit from reduced acid depositions. However, numerical simulations with the RAINS model indicate that differences in costs and acid depositions are negatively correlated when equally expensive cost-effective scenarios for Europe are compared, and scenarios ...

  4. Transaction Scripts: Making Implicit Scenarios Explicit

    OpenAIRE

    Moschoyiannis, S.; Razavi, A.; Krause, P.

    2010-01-01

    We describe a true-concurrent approach for managing dependencies between distributed and concurrent coordinator components of a long-running transaction. In previous work we have described how interactions specified in a scenario can be translated into a tuples-based behavioural description, namely vector languages. In this paper we show how reasoning against order-theoretic properties of such languages can reveal missing behaviours which are not explicitly described in the scenario but are s...

  5. Event scenarios of development of ukraine

    OpenAIRE

    Панасенко, С. В.

    2015-01-01

    The article is devoted to solving the current problem of finding ways to develop Ukrainian society. Today even amid sharp massive contradictions, split between the people and formal authority, this question still remains open and needs to be solved. Analysis of recent researches and publications shows that the different scenarios and vectors of possible development of Ukraine are discussed. However, among the specified prospects we can see that the negative scenarios of the future of Ukraine ...

  6. Experiments, Passive Observation and Scenario Analysis

    DEFF Research Database (Denmark)

    Hoover, Kevin D.; Juselius, Katarina

    he develops in his famous monograph, The Probability Approach in Econometrics (1944). We show how, once the details of the analogy are systematically understood, the experimental analogy can be used to shed light on theory-consistent cointegrated vector autoregression (CVAR) scenario analysis. CVAR...... scenario analysis can be seen as a clear example of Haavelmo's 'experimental' approach; and, in turn, it can be shown to extend and develop Haavelmo's methodology and to address issues that Haavelmo regarded as unresolved....

  7. Pseudo-Dirac Scenario for Neutrino Oscillations

    OpenAIRE

    Kobayashi, Makoto; Lim, C. S.

    2000-01-01

    We argue how pseudo-Dirac scenario for neutrinos leads to rich neutrino oscillation phenomena, including oscillation inside each generation. The pseudo-Dirac scenario is generalized by incorporating generation mixings and formulae for the various neutrino oscillations are derived. As the application we compare the formulae with the corresponding data. We find that observed pattern of mixings, such as almost maximal mixing in the atmospheric neutrino oscillation, is naturally explained in the ...

  8. The negaWatt 2011 scenario

    International Nuclear Information System (INIS)

    This article presents the approach adopted for the negaWatt scenario and its obtained results. It is based on sobriety (energy savings), on energy efficiency, and on the use of renewable energies. After having outlined the different reasons for an energy transition (increasing energy consumption, critics and risks related to nuclear energy, and high potential of renewable energies), the scenario is presented with its main principles. The scenario identifies possibilities ranging from half to two thirds of energy saving in the different energy consuming sectors. The building sector is presented as a major issue. The transport is described as a sector to be addressed on the long term. The necessary change of the industry sector is highlighted. The agriculture sector is presented as being at the heart of transition. Energy usages are to become sober, efficient and renewable. The scenario is based on a high rate development of renewable energies, while fossil energies are to become marginal, nuclear is to be progressively and reasonably given up, and networks are to become compatible to ensure the scenario success. Thus, the scenario demonstrates the feasibility of a 100 pc sustainable assessment for primary energy, complies with stakes and objectives by 2050. The cost of energy transition is briefly discussed

  9. Future nuclear energy scenarios for Europe

    International Nuclear Information System (INIS)

    Nuclear energy is back on the agenda worldwide. In order to prepare for the next decades and to set priorities in nuclear R and D and investment, market share scenarios are evaluated. This allows to identify the triggers which influence the market penetration of future nuclear reactor technologies. To this purpose, scenarios for a future nuclear reactor park in Europe have been analysed applying an integrated dynamic process modelling technique. Various market share scenarios for nuclear energy are derived including sub-variants with regard to the intra-nuclear options taken, e.g. introduction date of Gen-III (i.e. EPR) and Gen-IV (i.e. SCWR, HTR, FR) reactors, level of reprocessing, and so forth. The assessment was undertaken using the DANESS code which allows to provide a complete picture of mass-flow and economics of the various nuclear energy system scenarios. The analyses show that the future European nuclear park will exist of combinations of Gen-III and Gen-IV reactors. This mix will always consist of a set of reactor types each having its specific strengths. Furthermore, the analyses highlight the triggers influencing the choice between different nuclear energy deployment scenarios. In addition, a dynamic assessment is made with regard to manpower requirements for the construction of a future nuclear fleet in the different scenarios. (authors)

  10. Projections of mid-century summer air-quality for North America: effects of changes in climate and precursor emissions

    OpenAIRE

    Kelly, J; P. A. Makar; Plummer, D. A.

    2012-01-01

    Ten year simulations of North American current and future air-quality were carried out using a regional air-quality model driven by a regional climate model, in turn driven by a general circulation model. Three separate summer scenarios were performed: a scenario representing the years 1997 to 2006, and two SRES A2 climate scenarios for the years 2041 to 2050. The first future climate scenario makes use of 2002 anthropogenic precursor emissions, and the second applied emissions scaling factor...

  11. Air Pollution.

    Science.gov (United States)

    Air quality is affected by many types of pollutants that are emitted from various sources, including stationary and mobile. These sources release both criteria and hazardous air pollutants, which cause health effects, ecological harm, and material damage. They are generally categ...

  12. Numerical assessment of non-uniform corrosion scenarios of rebar in concrete exposed to natural chloride environment

    Indian Academy of Sciences (India)

    S Muthulingam; B N Rao

    2015-06-01

    Corrosion of embedded rebars is a classical deterioration mechanism that remains as one of the most significant problems limiting the service life of concrete structures exposed to chloride-laden environments. The primary objective of this study is to propose and verify a numerical framework that can efficiently quantify non-uniform corrosion penetration depth along the perimeter of the rebar in concrete exposed to chloride environment. This framework investigates the corrosion process during both the corrosion initiation and propagation phases by exploring the effects of not only the rebar existence but also its sizes and locations. The corrosion initiation phase is examined through a comprehensive chloride ingress model that identifies the most important parameters that influence the intrusion of chlorides into RC. The corrosion propagation phase is studied based on a decisive parameter, namely, the corrosion rate. In addition, the framework evaluates the non-uniform corrosion states that correspond to two scenarios of corrosion penetration depth: corrosion of segment of the rebar and uneven corrosion along the rebar perimeter. Numerical solution shows that, in general, chloride build-up along the perimeter of the corner bar is not only faster but also higher than that of the middle bar. Moreover, for the given values of cover thickness and water-to-binder ratio, time-to-corrosion initiation for the corner bar is faster than that for the middle bar. Furthermore, the larger the rebar, in general, the bigger the obstruction, and therefore, the higher the chloride build-up. Qualitative comparisons of the evaluated non-uniform corrosion scenarios with the variety of available laboratory and field data show good agreement.

  13. Analysis of the energy scenario Negawatt 2006; Analyse du scenario energetique negaWatt 2006

    Energy Technology Data Exchange (ETDEWEB)

    Acket, C.; Bacher, P

    2006-10-15

    The association Negawatt published in 2003 an energy scenario for the France in 2050, under the name of Negawatt 2006. This document aims to analyze the scenario Negawatt with a comparison of the scenario published on the web site of SLC, Save the Climate. The authors analyzes the main three sectors: electricity, transports and residential to propose their comparison in conclusion. (A.L.B.)

  14. EDITORIAL: Where next with global environmental scenarios? Where next with global environmental scenarios?

    Science.gov (United States)

    O'Neill, Brian; Pulver, Simone; Van Deveer, Stacy; Garb, Yaakov

    2008-12-01

    Scenarios have become a standard tool in the portfolio of techniques that scientists and policy-makers use to envision and plan for the future. Defined as plausible, challenging and relevant stories about how the future might unfold that integrate quantitative models with qualitative assessments of social and political trends, scenarios are a central component in assessment processes for a range of global issues, including climate change, biodiversity, agriculture, and energy. Yet, despite their prevalence, systematic analysis of scenarios is in its beginning stages. Fundamental questions remain about both the epistemology and scientific credibility of scenarios and their roles in policymaking and social change. Answers to these questions have the potential to determine the future of scenario analyses. Is scenario analysis moving in the direction of earth system governance informed by global scenarios generated through increasingly complex and comprehensive models integrating socio-economic and earth systems? Or will global environmental scenario analyses lose favour compared to more focused, policy-driven, regionally specific modelling? These questions come at an important time for the climate change issue, given that the scenario community, catalyzed by the Intergovernmental Panel on Climate Change (IPCC), is currently preparing to embark on a new round of scenario development processes aimed at coordinating research and assessment, and informing policy, over the next five to ten years. These and related questions about where next to go with global environmental scenarios animated a workshop held at Brown University (Note1) that brought together leading practitioners and scholars of global environmental change scenarios from research, policy-making, advocacy, and business settings. The workshop aimed to provide an overview of current practices/best practices in scenario production and scenario use across a range of global environmental change arenas. Participants

  15. South Korean energy scenarios show how nuclear power can reduce future energy and environmental costs

    International Nuclear Information System (INIS)

    South Korea is an important case study for understanding the future role of nuclear power in countries with on-going economic growth, and limited renewable energy resources. We compared quantitatively the sustainability of two ‘future-mapping’ exercises (the ‘Governmental’ scenario, which relies on fossil fuels, and the Greenpeace scenario, which emphasises renewable energy and excludes nuclear power). The comparison was based on a range of environmental and technological perspectives, and contrasted against two additional nuclear scenarios that instead envisage a dominant role for nuclear energy. Sustainability metrics included energy costs, external costs (greenhouse-gas emissions, air pollutants, land transformation, water consumption and discharge, and safety) and additional costs. The nuclear-centred scenarios yielded the lowest total cost per unit of final energy consumption by 2050 ($14.37 GJ−1), whereas the Greenpeace scenario has the highest ($25.36 GJ−1). We used probabilistic simulations based on multi-factor distributional sampling of impact and cost metrics to estimate the overlapping likelihoods among scenarios to understand the effect of parameter uncertainty on the integrated recommendations. Our simulation modelling implies that, despite inherent uncertainties, pursuing a large-scale expansion of nuclear-power capacity offers the most sustainable pathway for South Korea, and that adopting a nuclear-free pathway will be more costly and produce more greenhouse-gas emissions. - Highlights: • Nuclear power has a key role to play in mitigating greenhouse-gas emissions. • The Greenpeace scenario has higher total external cost than the nuclear scenarios. • The nuclear-centred scenarios offer the most sustainable option for South Korea. • The similar conclusions are likely to apply to other Asian countries

  16. Carbon-constrained scenarios. Final report

    International Nuclear Information System (INIS)

    This report provides the results of the study entitled 'Carbon-Constrained Scenarios' that was funded by FONDDRI from 2004 to 2008. The study was achieved in four steps: (i) Investigating the stakes of a strong carbon constraint for the industries participating in the study, not only looking at the internal decarbonization potential of each industry but also exploring the potential shifts of the demand for industrial products. (ii) Developing an hybrid modelling platform based on a tight dialog between the sectoral energy model POLES and the macro-economic model IMACLIM-R, in order to achieve a consistent assessment of the consequences of an economy-wide carbon constraint on energy-intensive industrial sectors, while taking into account technical constraints, barriers to the deployment of new technologies and general economic equilibrium effects. (iii) Producing several scenarios up to 2050 with different sets of hypotheses concerning the driving factors for emissions - in particular the development styles. (iv) Establishing an iterative dialog between researchers and industry representatives on the results of the scenarios so as to improve them, but also to facilitate the understanding and the appropriate use of these results by the industrial partners. This report provides the results of the different scenarios computed in the course of the project. It is a partial synthesis of the work that has been accomplished and of the numerous exchanges that this study has induced between modellers and stakeholders. The first part was written in April 2007 and describes the first reference scenario and the first mitigation scenario designed to achieve stabilization at 450 ppm CO2 at the end of the 21. century. This scenario has been called 'mimetic' because it has been build on the assumption that the ambitious climate policy would coexist with a progressive convergence of development paths toward the current paradigm of industrialized countries: urban sprawl, general

  17. Water use implications of biofuel scenarios

    Science.gov (United States)

    Teter, J.; Mishra, G. S.; Yeh, S.

    2012-12-01

    Existing studies rely upon attributional lifecycle analysis (LCA) approaches to estimate water intensity of biofuels in liters of irrigated/evapotranspiration water consumed for biofuel production. Such approaches can be misleading. From a policy perspective, a better approach is to compare differential water impacts among scenarios on a landscape scale. We address the shortcomings of existing studies by using consequential LCA, and incorporate direct and indirect land use (changes) of biofuel scenarios, marginal vs. average biofuel water use estimates, future climate, and geographic heterogeneity. We use the outputs of a partial equilibrium economic model, climate and soil data, and a process-based crop-soil-climate-water model to estimate differences in green water (GW - directly from precipitation to soil) and blue water (BW - supplied by irrigation) use among three scenarios: (1) business-as-usual (BAU), (2) Renewable Fuels Standard (RFS) mandates, and (3) a national Low Carbon Fuel Standard (LCFS) plus the RFS scenario. We use spatial statistical methods to interpolate key climatic variables using daily climate observations for the contiguous USA. Finally, we use FAO's crop model AquaCrop to estimate the domestic GW and BW impacts of biofuel policies from 2007-2035. We assess the differences among scenarios along the following metrics: (1) crop area expansion at the county level, including prime and marginal lands, (2) crop-specific and overall annual/seasonal water balances including (a) water inflows (irrigation & precipitation), (b) crop-atmosphere interactions: (evaporation & transpiration) and (d) soil-water flows (runoff & soil infiltration), in mm 3 /acre over the relevant time period. The functional unit of analysis is the BW and GW requirements of biofuels (mm3 per Btu biofuel) at the county level. Differential water use impacts among scenarios are a primarily a function of (1) land use conversion, in particular that of formerly uncropped land classes

  18. Arctic shipping emissions inventories and future scenarios

    Directory of Open Access Journals (Sweden)

    J. J. Corbett

    2010-10-01

    Full Text Available This paper presents 5 km×5 km Arctic emissions inventories of important greenhouse gases, black carbon and other pollutants under existing and future (2050 scenarios that account for growth of shipping in the region, potential diversion traffic through emerging routes, and possible emissions control measures. These high-resolution, geospatial emissions inventories for shipping can be used to evaluate Arctic climate sensitivity to black carbon (a short-lived climate forcing pollutant especially effective in accelerating the melting of ice and snow, aerosols, and gaseous emissions including carbon dioxide. We quantify ship emissions scenarios which are expected to increase as declining sea ice coverage due to climate change allows for increased shipping activity in the Arctic. A first-order calculation of global warming potential due to 2030 emissions in the high-growth scenario suggests that short-lived forcing of ~4.5 gigagrams of black carbon from Arctic shipping may increase global warming potential due to Arctic ships' CO2 emissions (~42 000 gigagrams by some 17% to 78%. The paper also presents maximum feasible reduction scenarios for black carbon in particular. These emissions reduction scenarios will enable scientists and policymakers to evaluate the efficacy and benefits of technological controls for black carbon, and other pollutants from ships.

  19. Integrated modelling of ITER scenarios with ECCD

    International Nuclear Information System (INIS)

    Full text: The main application of EC waves in ITER will be the control of NTM by means of the top launchers. However, virtually every ITER scenario would profit from appropriate use of ECCD by means of the equatorial launcher. In particular, hybrid and steady-state scenarios require off-axis current drive in order to either keep the safety factor above 1 or produce negative shear in a large part of the plasma cross-section. In this type of applications, alignment of the current sources and self-consistency of current and temperature profiles are critical issues, which can only be addressed by integrated modelling. To this end, the CRONOS suite of codes has been applied to the simulation of these scenarios. CRONOS integrates, in a modular structure, general 2-D magnetic equilibria, radiation and particle losses, several heat, particle and impurities transport models, as well as heat, particle and momentum source modules, associated, e.g., with neutral beams, radio-frequency waves, pellet ablation, etc. The ECCD module includes toroidal ray-tracing and linear computation of the driven current, which is generally adequate for ITER parameters. This presentation will give a short description of the CRONOS suite of codes, followed by results of simulations of ITER hybrid scenarios assisted by ECCD. Use of ECCD in steady-state scenarios will also be addressed. (author)

  20. Development of nonproliferation and assessment scenarios.

    Energy Technology Data Exchange (ETDEWEB)

    Finley, Melissa; Barnett, Natalie Beth

    2005-10-01

    The overall objective of the Nonproliferation and Assessments Scenario Development project is to create and analyze potential and plausible scenarios that would lead to an adversary's ability to acquire and use a biological weapon. The initial three months of funding was intended to be used to develop a scenario to demonstrate the efficacy of this analysis methodology; however, it was determined that a substantial amount of preliminary data collection would be needed before a proof of concept scenario could be developed. We have dedicated substantial effort to determine the acquisition pathways for Foot and Mouth Disease Virus, and similar processes will be applied to all pathogens of interest. We have developed a biosecurity assessments database to capture information on adversary skill locales, available skill sets in specific regions, pathogen sources and regulations involved in pathogen acquisition from legitimate facilities. FY06 funding, once released, will be dedicated to data collection on acquisition, production and dissemination requirements on a pathogen basis. Once pathogen data has been collected, scenarios will be developed and scored.

  1. Scenarios selection for a simple concept landfill

    International Nuclear Information System (INIS)

    Scenarios are used to deal with uncertainty on the evolution of complex systems. The scenario selection methodologies also have to provide a basis for reflexion and traceability of the reasoning. A scenario selection method has been developed for the case of disposal of uranium mill tailings in a landfill site. In the case of a simple concept landfill, a methodology that fulfils these requirements has been developed. It distinguishes on the one hand the landfill evolution, and on the other hand, the human behavior evolution. It is based on three steps: (i) characterization of the landfill itself, in order to define situations leading to releases of radionuclides, (ii) characterization of the human behavior in order to define situations leading to intrusions, and (iii) characterization of the interfaces between the two subsystems, in order to identify situations which could lead to a radiological risk for man. The method, applied to performance assessment for landfill of uranium mill tailings, has led to one reference scenario, and five altered scenarios taking into account specific landfill evolutions such as loss of covering or loss of integrity of the dike, and human intrusions such as housing on the site of landfill or excavation of the site. Copyright (2001) Material Research Society

  2. Energy scenarios for the 21. century

    International Nuclear Information System (INIS)

    The Canadian Energy Research Institute (CERI) has adopted a scenario approach in developing its energy outlook to 2025. These scenarios can be used in developing strategies to optimize opportunities and avoid the dangers that often accompany the more deterministic approach to forecasting. The scenarios are not predictions, but are instead feasible outcomes for the future. They encompass 5 major areas of uncertainty for the world energy market through 2025 that impact energy demand and fuel mix. These include the economy, technology, energy policy, resource availability, and market structure. The drivers for the energy scenarios are the environment, demography, economics, culture geopolitics and technology. The paper referred to the world energy market, the OECD energy markets, the non-OECD energy markets and the FSU energy markets under 3 energy scenarios including: (1) the material world in which the new economy drives the global economy, (2) a very dark Orwellian world in which there is a rise in terrorism and a breakdown in international cooperation, and (3) a utopia in which the major powers become increasingly serious about achieving sustainable development. 22 refs., 48 figs

  3. Thin air

    OpenAIRE

    Jasanoff, Sheila

    2013-01-01

    Clearing the air How do we grasp the air? Without Michel Callon’s guidance, I might never have asked that question. Years ago, when I first entered environmental law practice, I took it for granted that problems such as air pollution exist “out there” in the real world for science to discover and law to fix. It is a measure of Callon’s influence that I understand the law today as a metaphysical instrument, no less powerful in its capacity to order nature than the tools of the ancient oracular...

  4. Scenarios and design: Scoping the dialogue space

    DEFF Research Database (Denmark)

    Selin, Cynthia Lea; Kimbell, Lucy; Ramirez, Rafael;

    2015-01-01

    This paper examines the intersections between two futures-oriented domains of practice and research: scenario planning and design. Both are practice-led, with uneasy but productive relationships with theorizing. Exploring their relations offers ways to address challenges faced by interdisciplinary...... fields. We present nine themes that capture the links and spaces between design and scenarios, yet suggest that they are not a straightforward overlap or a simple relationship, but rather a range of interactions between the fields, including feeding in, bridging, tension and repulsion. The paper......'s contribution is to suggest how scenario planning can engage with design, resulting in new opportunities for research and projects. These modes of engagement provide a framing to explore dialogues between other management disciplines....

  5. Waterflooding optimization in uncertain geological scenarios

    DEFF Research Database (Denmark)

    Capolei, Andrea; Suwartadi, Eka; Foss, Bjarne;

    2013-01-01

    In conventional waterflooding of an oil field, feedback based optimal control technologies may enable higher oil recovery than with a conventional reactive strategy in which producers are closed based on water breakthrough. To compensate for the inherent geological uncertainties in an oil field...... realizations is maximized. In this paper, we both consider an open-loop optimization scenario, with no feedback, and a closed-loop optimization scenario. The closed-loop scenario is implemented in a moving horizon manner and feedback is obtained using an ensemble Kalman filter for estimation of the....... It uses the mean of the ensemble as its permeability field. Simulations reveal that the RO strategy and the certainty equivalent strategy give a higher NPV compared to the reactive strategy. Surprisingly, the RO strategy and the certainty equivalent strategy give similar NPVs. Consequently, the...

  6. Market structure scenarios in international steam coal

    Energy Technology Data Exchange (ETDEWEB)

    Trueby, Johannes; Paulus, Moritz

    2011-04-15

    The seaborne steam coal market changed in recent years. Trade volumes grew dynamically, important players emerged and since 2007 prices increased significantly and remained relatively high since then. In this paper we analyse market equilibria in the years 2006 and 2008 by testing for two possible market structure scenarios in this market: perfect competition and an oligopoly setup with major exporters competing in quantities. We conclude from our results that international steam coal trade is not perfectly competitive as there is a large spread between marginal costs and prices and a low capacity utilisation in 2008. Further, trade flows are generally more diversified in reality than in the competitive scenario. However, also the Cournot scenarios fail to accurately explain real market outcomes. We conclude that only more sophisticated models of strategic behaviour can predict market equilibria in international steam coal trade. (orig.)

  7. RESGen: Renewable Energy Scenario Generation Platform

    DEFF Research Database (Denmark)

    Iversen, Jan Emil Banning; Pinson, Pierre

    2016-01-01

    studies remains. Consequently, our aim here is to propose an open-source platform for space-time probabilistic forecasting of renewable energy generation (wind and solar power). This document covers both methodological and implementation aspects, to be seen as a companion document for the open-source...... scenario generation platform. It can generate predictive densities, trajectories and space-time interdependencies for renewable energy generation. The underlying model works as a post-processing of point forecasts. For illustration, two setups are considered: the case of day-ahead forecasts to be issued......Space-time scenarios of renewable power generation are increasingly used as input to decision-making in operational problems. They may also be used in planning studies to account for the inherent uncertainty in operations. Similarly using scenarios to derive chance-constraints or robust...

  8. Nuclear Futures Analysis and Scenario Building

    International Nuclear Information System (INIS)

    This LDRD project created and used advanced analysis capabilities to postulate scenarios and identify issues, externalities, and technologies associated with future ''things nuclear''. ''Things nuclear'' include areas pertaining to nuclear weapons, nuclear materials, and nuclear energy, examined in the context of future domestic and international environments. Analysis tools development included adaptation and expansion of energy, environmental, and economics (E3) models to incorporate a robust description of the nuclear fuel cycle (both current and future technology pathways), creation of a beginning proliferation risk model (coupled to the (E3) model), and extension of traditional first strike stability models to conditions expected to exist in the future (smaller force sizes, multipolar engagement environments, inclusion of actual and latent nuclear weapons (capability)). Accomplishments include scenario development for regional and global nuclear energy, the creation of a beginning nuclear architecture designed to improve the proliferation resistance and environmental performance of the nuclear fuel cycle, and numerous results for future nuclear weapons scenarios

  9. KTM Tokamak operation scenarios software infrastructure

    International Nuclear Information System (INIS)

    One of the largest problems for tokamak devices such as Kazakhstan Tokamak for Material Testing (KTM) is the operation scenarios' development and execution. Operation scenarios may be varied often, so a convenient hardware and software solution is required for scenario management and execution. Dozens of diagnostic and control subsystems with numerous configuration settings may be used in an experiment, so it is required to automate the subsystem configuration process to coordinate changes of the related settings and to prevent errors. Most of the diagnostic and control subsystems software at KTM was unified using an extra software layer, describing the hardware abstraction interface. The experiment sequence was described using a command language. The whole infrastructure was brought together by a universal communication protocol supporting various media, including Ethernet and serial links. The operation sequence execution infrastructure was used at KTM to carry out plasma experiments.

  10. KTM Tokamak operation scenarios software infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Pavlov, V.; Baystrukov, K.; Golobkov, YU.; Ovchinnikov, A.; Meaentsev, A.; Merkulov, S.; Lee, A. [National Research Tomsk Polytechnic University, Tomsk (Russian Federation); Tazhibayeva, I.; Shapovalov, G. [National Nuclear Center (NNC), Kurchatov (Kazakhstan)

    2014-10-15

    One of the largest problems for tokamak devices such as Kazakhstan Tokamak for Material Testing (KTM) is the operation scenarios' development and execution. Operation scenarios may be varied often, so a convenient hardware and software solution is required for scenario management and execution. Dozens of diagnostic and control subsystems with numerous configuration settings may be used in an experiment, so it is required to automate the subsystem configuration process to coordinate changes of the related settings and to prevent errors. Most of the diagnostic and control subsystems software at KTM was unified using an extra software layer, describing the hardware abstraction interface. The experiment sequence was described using a command language. The whole infrastructure was brought together by a universal communication protocol supporting various media, including Ethernet and serial links. The operation sequence execution infrastructure was used at KTM to carry out plasma experiments.

  11. Emission Scenarios for Methane and Nitrous Oxides from the Agricultural Sector in the EU-25

    OpenAIRE

    Hoeglund-Isaksson, L.; W. Winiwarter; Z. Klimont; I. Bertok

    2006-01-01

    This report presents three emission scenarios of non-CO2 greenhouse gases from the agricultural sector of the EU-25 until 2020. These scenarios explore the likely implications of changes in agricultural production due to the - implementations of the EU Agenda 2000 CAP Reform of 1999 and the EU Nitrates Directive of 1991 (as used for the analyses of the EU Clean Air for Europe (CAFE) programme), - the implementation of the 2003 Mid-term review of the CAP reform and from anticipated i...

  12. Energy scenarios for hydrogen production in Mexico

    International Nuclear Information System (INIS)

    The hydrogen is a clean and very efficient fuel, its combustion does not produce gases of greenhouse effect, ozone precursors and residual acids. Also the hydrogen produced by friendly energy sources with the environment like nuclear energy could help to solve the global problems that it confronts the energy at present time. Presently work fuel cycles of hydrogen production technologies in Mexico are judged, by means of a structured methodology in the concept of sustainable development in its social, economic and environmental dimensions. The methodology is divided in three scenarios: base, Outlook 2030 and capture of CO2. The first scenario makes reference to cycles analysis in a current context for Mexico, the second taking in account the demand projections reported by the IAEA in its report Outlook and the third scenario, capture of CO2, the technologies are analyzed supposing a reduction in capture costs of 75%. Each scenario also has four cases (base, social, environmental and economic) by means of which the cycles are analyzed in the dimensions of sustainable development. For scenarios base and capture, results show that combination nuclear energy- reformed of gas it is the best alternative for cases base and economic. For social case, the evaluated better technology is the hydraulics, and for environmental case, the best option is represented by the regenerative thermochemistry cycles. The scenario Outlook 2030 show a favorable tendency of growth of renewable sources, being the aeolian energy the best technology evaluated in the cases base and environmental, the hydraulics technology in the social case and in the economic case the reformed of natural gas that uses nuclear heat. (Author)

  13. Electron-cooling scenarios at Fermilab

    International Nuclear Information System (INIS)

    According to Run II upgrade plans, peak luminosity of the proton-antiproton beams in the Tevatron has to increase 7-8 times in coming years. This requires 5-6 times more antiprotons, which is supposed to be reached by means of electron cooling of accumulated pbars. A main scenario is to apply this in the Recycler (RR). However, there is an alternative, i.e to e-cool pbars in the accumulator, without using RR at all. Advantages and disadvantages of both scenarios are discussed

  14. Computational Scenario-based Capability Planning

    CERN Document Server

    Abbass, Hussein; Dam, Helen; Baker, Stephen; Whitacre, James M; Sarker, Ruhul; 10.1145/1389095.1389378

    2009-01-01

    Scenarios are pen-pictures of plausible futures, used for strategic planning. The aim of this investigation is to expand the horizon of scenario-based planning through computational models that are able to aid the analyst in the planning process. The investigation builds upon the advances of Information and Communication Technology (ICT) to create a novel, flexible and customizable computational capability-based planning methodology that is practical and theoretically sound. We will show how evolutionary computation, in particular evolutionary multi-objective optimization, can play a central role - both as an optimizer and as a source for innovation.

  15. 500 GeV ILC Operating Scenarios

    CERN Document Server

    Brau, James E; Barklow, T; Brau, J; Fujii, K; Gao, J; List, J; Walker, N; Yokoya, K

    2015-01-01

    The ILC Technical Design Report documents the design of a 500 GeV linear collider, but does not specify the center-of-mass energy steps of operation for the collider. The ILC Parameters Joint Working Group has studied possible running scenarios, including a realistic estimate of the real time accumulation of integrated luminosity based on ramp-up and upgrade processes, and considered the evolution of the physics outcomes. These physics goals include Higgs precision measurements, top quark measurements and searches for new physics. We present an "optimized" operating scenario and the anticipated evolution of the precision of the ILC measurements.

  16. The Impact of Gamification - Recommending Education Scenarios

    Directory of Open Access Journals (Sweden)

    Kai Erenli

    2013-01-01

    Full Text Available Many students play (computer games in their leisure time, thus acquiring skills which can easily be utilized when it comes to teaching more sophisticated knowledge. Nevertheless many educators today are wasting this opportunity. Some have evaluated gaming scenarios and methods for teaching students and have created the term “gamification”. This paper describes the history of this new term and explains the possible impact on teaching. It will take well-researched facts into consideration to discuss the potential of games. Moreover, scenarios will be illustrated and evaluated for educators to adopt and use on their own.

  17. Using Service Scenarios to Model Business Services

    DEFF Research Database (Denmark)

    Bækgaard, Lars

    The purpose of the paper is to present and evaluate the notion of service scenarios. A service is work done by a service executor in interaction with a service consumer. A service scenario is a model of a service system and the roles that are played by the actors participating and interacting dur...... a case study in a public library. The case study indicates that service systems should be understood as socio-technical systems in which service executors and service consumers co-create value in mutual interaction with each other and with a set of shared resources....

  18. Air Pollution

    Science.gov (United States)

    ... to a close in June 2013 when the company, Conscious Clothing, was awarded the My Air grand ... Page Options: Request Translation Services Facebook Twitter LinkedIn Google+ Reddit Email Evernote More Increase Font Size Decrease ...

  19. Mediated Scenarios: The Infusion of Art and Design in Scenario Practices

    DEFF Research Database (Denmark)

    Selin, Cynthia Lea

    2014-01-01

    Fellowship investigates scenarios mediated through cutting-edge gaming,visualization, simulation and design techniques. The focus on mediated practices of foresight pushes beyond an infusion of art and design into scenarios in an instrumental way, making moreaesthetically palatable futures. Rather what I...

  20. A new scenario framework for Climate Change Research: scenario matrix architecture

    NARCIS (Netherlands)

    van Vuuren, D.P.; Kriegler, E.; O'Neill, B.C.; Ebi, K.L.; Riahi, K.; Carter, T.R.; Edmonds, J.; Hallegatte, S.; Kram, T.; Mathur, R.; Winkler, H.

    2014-01-01

    This paper describes the scenario matrix architecture that underlies a framework for developing new scenarios for climate change research. The matrix architecture facilitates addressing key questions related to current climate research and policy-making: identifying the effectiveness of different ad

  1. Scenario-based roadmapping assessing nuclear technology development paths for future nuclear energy system scenarios

    International Nuclear Information System (INIS)

    Nuclear energy may play a significant role in a future sustainable energy mix. The transition from today's nuclear energy system towards a future more sustainable nuclear energy system will be dictated by technology availability, energy market competitiveness and capability to achieve sustainability through the nuclear fuel cycle. Various scenarios have been investigated worldwide each with a diverse set of assumptions on the timing and characteristics of new nuclear energy systems. Scenario-based roadmapping combines the dynamic scenario-analysis of nuclear energy systems' futures with the technology roadmap information published and analysed in various technology assessment reports though integrated within the nuclear technology roadmap Nuclear-Roadmap.net. The advantages of this combination is to allow mutual improvement of scenario analysis and nuclear technology roadmapping providing a higher degree of confidence in the assessment of nuclear energy system futures. This paper provides a description of scenario-based roadmapping based on DANESS and Nuclear-Roadmap.net. (author)

  2. Urban air quality in Europe

    International Nuclear Information System (INIS)

    This book provides an overview of air quality in urban environments in Europe, focusing on air pollutant emission sources and formation mechanisms, measurement and modeling strategies, and future perspectives. The emission sources described are biomass burning, vehicular traffic, industry and agriculture, but also African dust and long-range transport of pollutants across the European regions. The impact of these emission sources and processes on atmospheric particulate matter, ozone, nitrogen oxides and volatile and semi-volatile organic compounds is discussed and critical areas for particulate matter and nitrogen dioxide in Europe are identified. Finally, this volume presents future perspectives, mainly regarding upcoming air quality monitoring strategies, metrics of interest, such as submicron and nanoparticles, and indoor and outdoor exposure scenarios.

  3. Urban air quality management. V. 1

    International Nuclear Information System (INIS)

    This is the first in a series of reports commissioned by the International Petroleum Industry Environmental Conservation Association (IPIECA) to represent members' views on the management of urban air quality in the growing cities in developing countries. In this report, a general, science based framework is provided as a basis for understanding the nature of the problem in any specific urban area, the range of solutions that might be available, and the potential impact of each solution and its least cost privatisation. The topics covered are: a process for urban air quality management; setting air quality targets; a structured approach to the assessment of current and future air quality modelling methodologies; identification and collation of air quality model input data; development of socio-economic scenarios -long-term trend forecasting; cost effectiveness studies; the IPIECA approach to urban air quality management - development of partnerships; encouraging commitment to implementation of programme recommendations. (7 figures; 2 tables; 18 references). (UK)

  4. School Improvement Strategies That Work: Some Scenarios.

    Science.gov (United States)

    Huberman, A. Michael

    1983-01-01

    School improvement strategies are presented in four scenarios: (1) high outcomes from enforced, stabilized use; (2) moderate to high outcomes from high mastery and low settledness; (3) moderate to low outcomes from program blunting or downsizing; and (4) failing, low levels of outcome from indifference and discouragement. (MD)

  5. Scenario-based table top simulations

    DEFF Research Database (Denmark)

    Broberg, Ole; Edwards, Kasper; Nielsen, J.;

    2012-01-01

    This study developed and tested a scenario-based table top simulation method in a user-driven innovation setting. A team of researchers worked together with a user group of five medical staff members from the existing clinic. Table top simulations of a new clinic were carried out in a simple model...

  6. Cell Load Balancing in Heterogeneous Scenarios

    DEFF Research Database (Denmark)

    Eduardo, Simao; Rodrigues, Antonio; Mihovska, Albena D.;

    2013-01-01

    Cell load imbalances in wireless networks degrade performance. Macro and small cell collocated deployments (heterogeneous scenario) constitutes a new problem for load balancing. This paper proposes a novel admission control algorithm for an optimal solution to the assignment of traffic flows. It...

  7. Improving Aircraft Design Robustness with Scenario Methods

    Directory of Open Access Journals (Sweden)

    A. Strohmayer

    2001-01-01

    Full Text Available Compared to other industries, the aerospace sector is characterized by long product cycles in a very complex environment. The aircraft manufacturer has to base his product strategy on a long-term view of risks and opportunities in the transport industry but he cannot predict the development of relevant factors in this market environment with any certainty. In this situation, scenario methods offer a pragmatic way to limit the uncertainties and to work them up methodically, in order to derive recommendations for cost-intensive strategic decisions like for example the go-ahead for a new aircraft concept. By including scenario methods in the aircraft design cycle, the ‘design robustness’ can be improved, i.e. the design is not optimised for a prognosticated operating environment, but can cope with various possible future developments. The paper will explain the three fundamental aspects in applying scenario planning to the aircraft design process: requirement definition, design evaluation and technology identification. For each aspect, methods will be shown, which connect the rather qualitative results of a scenario process with aircraft design, which typically demands a qualitative input.

  8. European Water Footprint Scenarios for 2050

    Directory of Open Access Journals (Sweden)

    A. Ertug Ercin

    2016-05-01

    Full Text Available This study develops water footprint scenarios for Europe for 2050, at the country level, based on projections regarding population and economic growth, production and trade patterns, consumption patterns (diets and bioenergy use and technological development. The objective is to estimate possible future changes in the green, blue and grey water footprint (WF of production and consumption, to analyze the main drivers of projected changes and to assess Europe’s future dependence on water resources elsewhere in the world. We develop four scenarios, considering globalization versus regional self-sufficiency, and development driven by economic objectives versus development driven by social and environmental objectives. The study shows that the most critical driver of change affecting Europe’s future WF is the consumption pattern. The WFs of both production and consumption in Western Europe increase under scenarios with high meat consumption and decrease with low-meat scenarios. Besides, additional water demands from increasing biofuel needs will put further pressure on European water resources. The European countries with a large ratio of external to total WF of consumption in 2000 decrease their dependencies on foreign water resources in 2050.

  9. National FCEV and Hydrogen Fueling Station Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Bush, Brian; Melaina, Marc

    2016-06-09

    This presentation provides a summary of the FY16 activities and accomplishments for NREL's national fuel cell electric vehicle (FCEV) and hydrogen fueling station scenarios project. It was presented at the U.S. Department of Energy Hydrogen and Fuel Cells Program 2016 Annual Merit Review and Peer Evaluation Meeting on June 9, 2016, in Washington, D.C.

  10. Scenarios for GCRT J1745-3009

    CERN Document Server

    Popov, S B

    2008-01-01

    I discuss several scenarios to explain properties of the radio transient source GCRT J1745-3009. Namely, a highly magnetized neutron star on the propeller or georotator stage, a transient propeller, and an ejector in a binary system are discussed. Simple populational estimates favor the transient propeller model.

  11. Use of simplifier scenarios for CRM training

    Science.gov (United States)

    Weatherly, D.

    1984-01-01

    Cockpit resource management (CRM) at Metro Airlines is discussed. The process by which the program of CRM training was initiated is mentioned. Management aspects of various flying scenarios are considered. The transfer of training from the classroom to the field is assessed.

  12. Future Scenarios for Mobile Science Learning

    Science.gov (United States)

    Burden, Kevin; Kearney, Matthew

    2016-01-01

    This paper adopts scenario planning as a methodological approach and tool to help science educators reconceptualise their use of mobile technologies across various different futures. These "futures" are set out neither as predictions nor prognoses but rather as stimuli to encourage greater discussion and reflection around the use of…

  13. Scenarios as methods of Community Building

    DEFF Research Database (Denmark)

    Rasmussen, Lauge Baungaard

    2002-01-01

    The significance of the scenario workshop is the combination of creativity, reflection and action helping the participants to imaging and realise desirable futures. It can contribute to fill the gaps between visions of the future and the present situation, giving the participants knowledge and po...... power to act themselves instead of just being passively adjusted to the ongoing changes of their organisation or community....

  14. Transport Technologies and Policy Scenarios to 2050

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-10-15

    As part of the major WEC study on Scenarios to 2050, a specific investigation was undertaken on measures required in the transport sector to secure sustainable energy and sustainable mobility in the future. This report outlines the results conducted by a study group of international WEC transport experts and gives concrete policy recommendations to develop sustainable transport systems.

  15. Sustainable Low Carbon Transport Scenarios for India

    DEFF Research Database (Denmark)

    Shukla, P.R.; Dhar, Subash; Mittal, Shivika

    2014-01-01

    are delineated that would facilitate the sustainable low carbon transformation of India’s transport sector. The long term energy and emission trajectory of India’s transport sector is assessed under alternate scenarios using the integrated assessment modelling framework. Co-benefits like energy...

  16. Scenario study on the FBR deployment

    International Nuclear Information System (INIS)

    This study on success scenarios for the Fast Breeder Reactor (FBR) deployment was performed taking account of future situation of fossil, renewable and nuclear energies in Japan as well as the world from the viewpoints of the following four items; economics, environment, energy security and restriction of natural uranium resources. In the economics scenario, if carbon tax is added to generating cost of LNG, coal and oil and the economics of FBR cycle is competitive with LWR cycle in the future, FBR cycle will be expected to introduce as the middle and base load power plant. In the environment scenario, there is also any possibility that FBR cycle which can burn and transmute minor actinide and fission product elements will be introduced in order to reduce the burden of deposit facility and the toxicity of high-level waste. In the uranium resources restriction scenario, FBR cycle needs to be deployed at the latest in the middle of 21st century from the viewpoint of the restriction of natural uranium resources. This study was carried out in a part of JNC's feasibility study on commercialized FBR cycle system. (author)

  17. Scenario-based Training: Director's Cut

    NARCIS (Netherlands)

    Peeters, M.M.M.; Van den Bosch, K.; Meyer, J-J.Ch.; Neerincx, M.A.

    2011-01-01

    Research regarding autonomous learning shows that freeplay does not result in optimal learning. Combining scenario-based training with intelligent agent technology off ers the possibility to create autonomous training enriched with automated adaptive support delivered by a director agent. We conduct

  18. Flooding Capability for River-based Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Curtis L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Prescott, Steven [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ryan, Emerald [Idaho State Univ., Pocatello, ID (United States); Calhoun, Donna [Boise State Univ., ID (United States); Sampath, Ramprasad [Centroid Labs., Los Angeles, CA (United States); Anderson, S. Danielle [Idaho National Lab. (INL), Idaho Falls, ID (United States); Casteneda, Cody [Boise State Univ., ID (United States)

    2015-10-01

    This report describes the initial investigation into modeling and simulation tools for application of riverine flooding representation as part of the Risk-Informed Safety Margin Characterization (RISMC) Pathway external hazards evaluations. The report provides examples of different flooding conditions and scenarios that could impact river and watershed systems. Both 2D and 3D modeling approaches are described.

  19. International scenarios of the Venezuelan oil industry

    International Nuclear Information System (INIS)

    The times of stability of the energy business, which characterized the 50s and the 60s came to their end in the 70s. From that moment on, new times have become times of quick changes and high uncertainty. In order to minimize the impact of the surprises that the future may bring, and so decrease the managers' decision making risk, many companies use the scenario planning process. The end purpose of scenario planning is the creation of an organization that will adapted to changes, a learning organization, that is able to identify the business environment un knows and to use this knowledge as one of its advantages. The present article shows the scenarios generated for the Venezuelan oil industry's strategic planning exercise for the 1999-2015 period. Theses scenarios are Consensus and Harmony, Regions and Environment, Conflicts and Decadence and Pragmatic Community. It is concluded from them that oil business success would be supported by differentiation as a secure, trusted and low cost producer; early oil and gas opportunities identification; Hemispherical integration and/or bilateral commercial agreements; oil and gas business portfolio diversification; and diversification to state-of-the-art technologies for renewable forms of energy

  20. Linguistic evaluation of terrorist scenarios: example application.

    Energy Technology Data Exchange (ETDEWEB)

    Darby, John L.

    2007-03-01

    In 2005, a group of international decision makers developed a manual process for evaluating terrorist scenarios. That process has been implemented in the approximate reasoning Java software tool, LinguisticBelief, released in FY2007. One purpose of this report is to show the flexibility of the LinguisticBelief tool to automate a custom model developed by others. LinguisticBelief evaluates combinations of linguistic variables using an approximate reasoning rule base. Each variable is comprised of fuzzy sets, and a rule base describes the reasoning on combinations of variables fuzzy sets. Uncertainty is considered and propagated through the rule base using the belief/plausibility measure. This report documents the evaluation and rank-ordering of several example terrorist scenarios for the existing process implemented in our software. LinguisticBelief captures and propagates uncertainty and allows easy development of an expanded, more detailed evaluation, neither of which is feasible using a manual evaluation process. In conclusion, the Linguistic-Belief tool is able to (1) automate an expert-generated reasoning process for the evaluation of the risk of terrorist scenarios, including uncertainty, and (2) quickly evaluate and rank-order scenarios of concern using that process.

  1. Probabilistic results for a mobile service scenario

    DEFF Research Database (Denmark)

    Møller, Jesper; Yiu, Man Lung

    We consider the following stochastic model for a mobile service scenario. Consider a stationary Poisson process in Rd, with its points radially ordered with respect to the origin (the anchor); if d = 2, the points may correspond to locations of e.g. restaurants. A user, with a location different...

  2. Risk Appraisal in Scripted Acquaintance Rape Scenarios.

    Science.gov (United States)

    Wright, Doris J.

    Cognitive appraisals are believed to influence how women judge or appraise risk in acquaintance interactions which lead to sexual assault. Ways in which men and women judge the presence of risk factors in scripted acquaintance rape scenarios, and whether alcohol was a significant factor in assessing risk, are examined in this paper. Participants…

  3. No-arbitrage bounds for financial scenarios

    DEFF Research Database (Denmark)

    Geyer, Alois; Hanke, Michael; Weissensteiner, Alex

    2014-01-01

    We derive no-arbitrage bounds for expected excess returns to generate scenarios used in financial applications. The bounds allow to distinguish three regions: one where arbitrage opportunities will never exist, a second where arbitrage may be present, and a third, where arbitrage opportunities will...

  4. Wiki Based Collaborative Learning in Interuniversity Scenarios

    Science.gov (United States)

    Katzlinger, Elisabeth; Herzog, Michael A.

    2014-01-01

    In business education advanced collaboration skills and media literacy are important for surviving in a globalized business where virtual communication between enterprises is part of the day-by-day business. To transform these global working situations into higher education, a learning scenario between two universities in Germany and Austria was…

  5. Scenarios Based on Shared Socioeconomic Pathway Assumptions

    Science.gov (United States)

    Edmonds, J.

    2013-12-01

    A set of new scenarios is being developed by the international scientific community as part of a larger program that was articulated in Moss, et al. (2009), published in Nature. A long series of meetings including climate researchers drawn from the climate modeling, impacts, adaptation and vulnerability (IAV) and integrated assessment modeling (IAM) communities have led to the development of a set of five Shared Socioeconomic Pathways (SSPs), which define the state of human and natural societies at a macro scale over the course of the 21st century without regard to climate mitigation or change. SSPs were designed to explore a range of possible futures consistent with greater or lesser challenges to mitigation and challenges to adaptation. They include a narrative storyline and a set of quantified measures--e.g. demographic and economic profiles--that define the high-level state of society as it evolves over the 21st century under the assumption of no significant climate feedback. SSPs can be used to develop quantitative scenarios of human Earth systems using IAMs. IAMs produce information about greenhouse gas emissions, energy systems, the economy, agriculture and land use. Each set of SSPs will have a different human Earth system realization for each IAM. Five groups from the IAM community have begun to explore the implications of SSP assumptions for emissions, energy, economy, agriculture and land use. We report the quantitative results of initial experiments from those groups. A major goal of the Moss, et al. strategy was to enable the use of CMIP5 climate model ensemble products for IAV research. CMIP5 climate scenarios used four Representative Concentration Pathway (RCP) scenarios, defined in terms of radiative forcing in the year 2100: 2.6, 4.5, 6.0, and 8.5 Wm-2. There is no reason to believe that the SSPs will generate year 2100 levels of radiative forcing that correspond to the four RCP levels, though it is important that at least one SSP produce a

  6. Forest associations and global climate change - current climatic conditions; Forest associations and global climate change - CCCM climatic scenario; Forest associations and global climate change - GISS climatic scenario; Forest associations and global climate change - dT1 climatic scenario; 1 : 1 000 000

    International Nuclear Information System (INIS)

    Bioclimatic areas of wood species represent the areas of natural spreading of wood species as determined by the threshold values of air temperature by climatic amplitudes established for the individual wood species. Establishment of climatic amplitudes of the individual wood species in Slovakia was based on the existing studies, which analysed the results of natural spreading of wood species in Slovakia in relation to the vertical climatic changes. The presented bioclimatic areas are assessed for the following conditions (table): · Tn contemporary climate; · CCCM (Canadian Climate Center Model) climatic scenario; · GISS (Goddard Institute for Space Studies) climatic scenario; · dT1 (National Climatic Programme) climatic scenario. (authors)

  7. Global climate-oriented transportation scenarios

    International Nuclear Information System (INIS)

    This paper develops scenarios whereby CO2 emissions from the transportation sector are eliminated worldwide by the end of this century. Data concerning the energy intensity and utilization of different passenger and freight transportation modes in 2005, and per capita income, in 10 different socio-economic regions of the world are combined with scenarios of population and per capita GDP to generate scenarios of future transportation energy demand. The impact of various technical options (improvements in the energy intensity of all transportation modes, changes in the proportions of vehicles with different drive trains, and a shift to biomass or hydrogen for the non-electricity energy requirements) and behavioural options (a shift to less energy-intensive LDV market segments, a reduction in total passenger-km of travel per capita, and an increase in the share of less energy-intensive passenger and freight modes of transport) is assessed. To eliminate transportation fossil fuel emissions within this century while limiting the demand for electricity, biofuels or hydrogen to manageable levels requires the simultaneous application of all the technical and behavioural measures considered here, with improvements in vehicle efficiencies and a shift to plug-in hybrid and battery-electric drive trains for light duty vehicles being the most important measures. - Highlights: ► Scenarios are developed whereby transportation CO2 emissions reach zero by 2100. ► These scenarios address concerns about peak oil and global warming. ► A comprehensive mix of technical and behavioural changes is considered in 10 world regions. ► Efficiency improvements and a shift to plug-in hybrid vehicles are the most important measures

  8. Negatep: A Scenario for Combating Global Warming

    International Nuclear Information System (INIS)

    There have been an increasing number of foresight exercises in the field of energy and global warming in recent years, as we have seen from the articles devoted to these questions by Futuribles in 2011 (both in this special issue and in the April number). It is certainly the case that the goals for greenhouse-gas emission reduction are rather ambitious, particularly in France, it being the aim of the 2005 French framework law on energy to reduce carbon gas discharges by a factor of four. Among these scenarios, the Negatep scenario developed by Claude Acket and Pierre Bacher from the 'Sauvons le climat' [Let's save the climate] Association proposes to achieve this ('factor 4') goal in France by 2050 by reducing fossil fuel use by 75% and replacing this as quickly as possible with electricity produced from non-carbon-gas-emitting sources - chiefly, nuclear power and renewables. The authors lay out their goals here, backed up by figures, comparing these with the reference scenario. They also show the path that must be followed to arrive at these goals, particularly in the residential and tertiary sectors, and in transport and industry (through control of needs and recourse to alternative energy sources). They close by comparing the Negatep scenario with two other more recent scenarios aimed also at reducing greenhouse gas emissions, on the one hand in Europe, and on the other in Germany. The comparison confirms that they were right to rely on electricity as a substitute for oil, but gives them cause for concern in respect of the consequences (formidable in their view) that the replacement of nuclear power and coal energy by intermittent renewable energies might have in Europe, both with regard to costs and to the effects on the power network. (authors)

  9. Study of the degradation mechanisms of zirconium alloy nuclear fuel claddings in air at high-temperature

    International Nuclear Information System (INIS)

    In nuclear plants, some accidental situations can result in air exposure of Pressurized Water Reactor (PWR) fuel assemblies: air ingress following a breach in the reactor vessel, de-flooding during handling, spent fuel storage pool de-flooding. Deprived of cooling source, the assemblies temperature raises and the fuel cladding, made out of zirconium based alloys, oxidize. Compared to a steam oxidation, the degradation kinetic of the cladding is higher, on the one hand because of the high enthalpy of the zirconium-oxygen reaction (compared to zirconium-steam reaction), on the other hand because of the nitrogen contribution to the degradation. Temperature escalation and reaction runaway are expected and can rapidly lead to the loss of integrity of the cladding tubes. The objective of this PhD thesis was to affine the understanding of the high temperature air oxidation mechanisms of the two mostly used zirconium alloys in French PWR, Zircaloy-4 and M5. Special attention has been paid to clarify the role of nitrogen. As-received Zircaloy-4 and M5 claddings segments have been oxidized in a thermo-balance in air in isothermal conditions at temperatures between 800 C and 1000 C. Several characterization techniques (micro-Raman spectroscopy, EPMA, XRD, optical and scanning electron microscopies...) have been used to analyze the oxide layers. Identification and evolution of the different phases (monoclinic, tetragonal and cubic zirconia, zirconium oxynitride and ZrN) has been evidenced and analyzed at several step of the oxidation process. Oxidation mechanisms have been proposed and the better oxidation resistance of the M5 alloy, compared to Zircaloy-4 alloy, has been explained. The collected information will allow improvement of modeling aiming to predict the behavior of the claddings in various accidental situations with air ingress (temperature transients, evolution of the gas phase composition...). (author)

  10. The future of scenarios: issues in developing new climate change scenarios

    International Nuclear Information System (INIS)

    In September, 2007, the IPCC convened a workshop to discuss how a new set of scenarios to support climate model runs, mitigation analyses, and impact, adaptation and vulnerability research might be developed. The first phase of the suggested new approach is now approaching completion. This article discusses some of the issues raised by scenario relevant research and analysis since the last set of IPCC scenarios were created (IPCC SRES, 2000) that will need to be addressed as new scenarios are developed by the research community during the second phase. These include (1) providing a logic for how societies manage to transition from historical paths to the various future development paths foreseen in the scenarios, (2) long-term economic growth issues, (3) the appropriate GDP metric to use (purchasing power parity or market exchange rates), (4) ongoing issues with moving from the broad geographic and time scales of the emission scenarios to the finer scales needed for impacts, adaptation and vulnerability analyses and (5) some possible ways to handle the urgent request from the policy community for some guidance on scenario likelihoods. The challenges involved in addressing these issues are manifold; the reward is greater credibility and deeper understanding of an analytic tool that does much to form the context within which many issues in addition to the climate problem will need to be addressed.

  11. Low carbon scenarios for transport in India: Co-benefits analysis

    DEFF Research Database (Denmark)

    Dhar, Subash; Shukla, P.R.

    2015-01-01

    imports, besides causing more CO2 emissions. The government of India wants to achieve the climate goals through a sustainability approach that simultaneously addresses other environment and developmental challenges. This paper analyses a sustainable low carbon transport (SLCT) scenario based on...... sustainable strategies for passenger and freight mobility, vehicle technologies and fuel using global CO2 prices that correspond to 2 °C global stabilisation target. The scenarios span from years 2010 to 2050 and are analysed using the energy system model-ANSWER MARKAL. The SLCT scenario has improved energy...... security (cumulative oil demand lower by 3100 Mtoe), improved air quality (PM 2.5 emissions never exceed the existing levels) and the cumulative CO2 emissions are lower by 13 billion t CO2 thereby showing that achieving development objectives with CO2 co-benefits is feasible....

  12. Scenario-based analyses of energy system development and its environmental implications in Thailand

    International Nuclear Information System (INIS)

    Thailand is one of the fastest growing energy-intensive economies in Southeast Asia. To formulate sound energy policies in the country, it is important to understand the impact of energy use on the environment over the long-period. This study examines energy system development and its associated greenhouse gas and local air pollutant emissions under four scenarios in Thailand through the year 2050. The four scenarios involve different growth paths for economy, population, energy efficiency and penetration of renewable energy technologies. The paper assesses the changes in primary energy supply mix, sector-wise final energy demand, energy import dependency and CO2, SO2 and NO x emissions under four scenarios using end-use based Asia-Pacific Integrated Assessment Model (AIM/Enduse) of Thailand

  13. Air surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Patton, G.W.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the air surveillance and monitoring programs currently in operation at that Hanford Site. Atmospheric releases of pollutants from Hanford to the surrounding region are a potential source of human exposure. For that reason, both radioactive and nonradioactive materials in air are monitored at a number of locations. The influence of Hanford emissions on local radionuclide concentrations was evaluated by comparing concentrations measured at distant locations within the region to concentrations measured at the Site perimeter. This section discusses sample collection, analytical methods, and the results of the Hanford air surveillance program. A complete listing of all analytical results summarized in this section is reported separately by Bisping (1995).

  14. Climatic trends in Estonia during the period of instrumental observations and climate scenarios

    International Nuclear Information System (INIS)

    Weather conditions in Estonia are quite variable. Long-term periodical fluctuations have been observed in meteorological values. At the same time, the climate change during the last 100-150 years is marked. As a general tendency, the climate has become more maritime. Air pressure is characterized by an increasing trend in spring and summer, and by a decreasing trend in autumn and winter. Mean air temperature has increased, particularly over the colder half of the year. Precipitation area totals have risen, most of all in autumn and winter. Snow cover duration has decreased significantly. General circulation model-based climate change scenarios expect a general increase in air temperature in Estonia with warming in winter more significant than that in summer. Moreover, they indicate an increase in precipitation, but the results of the individual models are quite variable. The transient scenario shows that the main increase in precipitation will not occur during next decades, but only at the end of the transient period, around 2070. It can be stated that observed tendencies of climate change in Estonia concur with expected changes caused by global warming. According to the long-term fluctuations of meteorological values in Estonia, changes different from general trends can take place during the next decade. An increase in mean air pressure, sunshine duration and snow cover duration, as well as a decrease in mean air temperature and precipitation is expected in the following years

  15. Climate change scenarios for Canada's national parks : a users manual

    International Nuclear Information System (INIS)

    A screening level impact assessment has shown that the implications of climate change for Canada's national parks are considerable. Climate change scenarios will be an important component in examining the potential climate change impacts and the implications of adaptation strategies. Most climate change scenarios are based on vulnerability, impact and adaptation research. This user's manual describes the development of 3 types of climate change scenarios including scenarios from global climate models (GCMs), bioclimate scenarios and daily scenarios for use by Parks Canada. The manual offers advice to first-time climate change scenario users in choosing and interpreting climate change, bioclimate and daily scenarios. It also addresses the theoretical and practical foundations of each climate scenario and shows how to access data regarding the various scenarios. Hands-on exercises are included as an interpretive aid. 20 refs., 4 tabs., 19 figs

  16. Business-as-usual, High Technology and Coalition Scenarios for Transboundary Pollution in the European Union

    OpenAIRE

    Pavlova, Y.

    2009-01-01

    The paper addresses the issue of air pollution in the European Union (EU). The focus is on economic and environmental assessment of alternative pollution control scenarios. In order to derive policy-relevant conclusions, we develop an ecology-economy model of the EU by linking an environmental effect from countries' SO2 (sulphur dioxide) abatement with their economic outcomes. We consider SO2 reduction strategies (GAINS) available for the EU member states during 2015-2020 and, compare ...

  17. Thermodynamic analysis of spent pyrochemical salts in the stored condition and in viable accident scenarios

    International Nuclear Information System (INIS)

    This study involves examining ''spent'' electrorefining (ER) salts in the form present after usage (as stored), and then after exposure to water in a proposed accident scenario. Additionally, the equilibrium composition of the salt after extended exposure to air was also calculated by computer modeling and those results are also presented herein. It should be noted that these salts are extremely similar to spent MSE salts from the Rocky Flats MSE campaigns using NaCl-KCl- MgCl2

  18. Highway Electrification And Automation Technologies - Regional Impacts Analysis Project: Phase I: Baseline Scenario Data Analysis

    OpenAIRE

    Scag; Path

    1993-01-01

    The Highway Electrification and Automation Technologies Regional Impacts Analysis Project addresses the transportation-related problems of freeway congestion, air pollution, and dependence on fossil fuels in southern California. This report presents a documentation of the basis for the impacts analysis. It contains sections on data collected, baseline forecast for 2025, and electrification and automation specification scenarios. This report constitutes the final report for Phase I of the proj...

  19. Modelling project feasibility robustness by use of scenarios

    OpenAIRE

    Rehfeld, Claus; Leleur, Steen

    1998-01-01

    Key words: Evaluation, Scenario, Uncertainty, Multi-Modal Abstract: This paper presents the application of a new scenario based analysis technique which has been developed for transport infrastructure planning. The approach aims at dealing with uncertainty in the planning environment in a more systematic way than is usually the case when applying scenario analysis. Specifically, the developed scenario approach secures a consistent inclusion of actual scenario elements in the quantitative impa...

  20. A new scenario framework for Climate Change Research: Scenario matrix architecture

    Energy Technology Data Exchange (ETDEWEB)

    Van Vuuren, Detlef; Kriegler, Elmar; O' Neill, Brian; Ebi, Kristie L.; Riahi, Keywan; Carter, Tim; Edmonds, James A.; Hallegatte, Stephane; Kram, Tom; Mathur, Ritu; Winkler, Harald

    2014-02-01

    In this paper, we present the scenario matrix architecture as part of the new scenario framework for climate change research. The matrix architecture focuses on a key question of current climate research, namely the identification of trade-offs and synergies (in terms of risks, costs and other consequences) of different adaptation and mitigation strategies. The framework has two main axes: 1) the level of forcing (as represented by the RCPs) and 2) different socio-economic reference pathways. The matrix can be used as a tool to guide new scenario development and analytical analysis. It can also be used as a heuristic tool for classifying new and existing scenarios for assessment. Key elements of the architecture, in particular the shared socio-economic reference pathways and the shared policy assumptions, are elaborated in other papers in this special issue.

  1. 3 Investment Scenarios for Fast Reactors

    International Nuclear Information System (INIS)

    Results: • 4 families of scenarios: – In each of them, 3 options for national nuclear policy → 12 scenarios; – 3 favorable to FRs: - “climate constraint” with strong pro-nuclear policy - “climate constraint” with moderate pro-nuclear policy - “totally green” with strong pro-nuclear policy. • Business As Usual is not favorable to Fast Reactors; Fast reactors deployment: - Needs strong climate policy - Is viable in case of important renewable progress as long as climate policy is strong. International perspective: • Results are valid for Europe, other drivers being likely to be more important in other countries : high growth and demand (Asia); • With strong contrasts between European countries. Further research: • Finer modeling of drivers with unclear influence (clustered and excluded variables): Influence of weak signals

  2. Selecting reasonable future land use scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Allred, W.E.; Smith, R.W. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1995-12-31

    This paper examines a process to help select the most reasonable future land use scenarios for hazardous waste and/or low-level radioactive waste disposal sites. The process involves evaluating future land use scenarios by applying selected criteria currently used by commercial mortgage companies to determine the feasibility of obtaining a loan for purchasing such land. The basis for the process is that only land use activities for which a loan can be obtained will be considered. To examine the process, a low-level radioactive waste site, the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory, is used as an example. The authors suggest that the process is a very precise, comprehensive, and systematic (common sense) approach for determining reasonable future use of land. Implementing such a process will help enhance the planning, decisionmaking, safe management, and cleanup of present and future disposal facilities.

  3. Elastic cross sections in an RSIIp scenario

    International Nuclear Information System (INIS)

    The elastic differential cross section is calculated at low energies (below 100 MeV) for the elements 3He, 20Ne, 40Ar, 14N, 12C, and for the 208Pb using a finite electromagnetic potential, which is obtained by considering a Randall–Sundrum II scenario modified by the inclusion of p compact extra-dimensions. The length scale is adjusted in the potential to compare with known experimental data and to set bounds for the parameter of the model. The effective four-dimensional (4D) electromagnetic potential is produced by a point charge, as seen from the three-brane that contains it, in uniform motion in an RSIIp scenario. (paper)

  4. Extreme scenarios for nuclear waste repositories

    International Nuclear Information System (INIS)

    Two extreme scenarios for release of radioactive waste have been constructed. In the first, a volcanic eruption releases 1 km2 of an underground nuclear waste repository, while in the second, waste enters the drinking water reservoir of a major city. With pessimistic assumptions, upper bounds on the number of cancers due to radiation are calculated. In the volcano scenario, the effects of the waste are smaller than the effects of natural radioactivity in the volcanic dust if the delay between emplacement and eruption exceeds 2000 yr. The consequences of the waste in drinking water depend on the survival time of the canisters and the rate of leaching of the nuclides from the waste matrix. For a canister life of 400 yr and a leach time of 6300 yr the cancer rate in the affected area would increase by 25%. (author)

  5. Revisiting light neutralino scenarios in the MSSM

    CERN Document Server

    Vasquez, Daniel Albornoz; Boehm, Celine

    2011-01-01

    We revisit the case of a light neutralino LSP in the framework of the MSSM. We consider a model with eleven free parameters. We show that all scenarios where the annihilation of light neutralinos rely mainly on the exchange of a light pseudoscalar are excluded by direct detection searches and by Fermi measurements of the gamma-flux from dwarf spheroidal galaxies. On the other hand, we find scenarios with light sleptons that satisfy all collider and astroparticle physics constraints. In this case, the lower limit on the LSP mass is 12.6 GeV. We discuss how the parameter space of the model will be further probed by new physics searches at the LHC.

  6. Scenario research: Can the future be predicted?

    DEFF Research Database (Denmark)

    Stacey, Julia; Sonne, Anne-Mette

    2000-01-01

    to genetic screening, the supermarket is aware of the fact that the Jensen family has a hereditary tendency to certain diseases and therefore should avoid certain foods. The supermarket makes sure that these foods never end up among the family's purchases. Nobody can predict the future and nobody knows...... whether the shopping situation described will become a reality, but attempts can be made to come up with qualified indications on possible development directions. In connection with a scenario research project, researchers from MAPP and the Danish Technological University have looked into the future...... of the Danish food industry. A scenario is a description of a possible and likely future and can be used to explore future developments. What will happen in the food industry if sales of functional foods increase? - What will happen if e-commerce seriously strikes through in the food industry? The purpose...

  7. Cold dark matter in brane cosmology scenario

    International Nuclear Information System (INIS)

    We analyze the dark matter problem in the context of brane cosmology. We investigate the impact of the non-conventional brane cosmology on the relic abundance of non-relativistic stable particles in high and low reheating temperature scenarios. We show that in case of high reheating temperature, the brane cosmology may enhance the dark matter relic density by many order of magnitudes and a stringent lower bound on the five dimensional scale is obtained. We also consider low reheating temperature scenarios with chemical equilibrium and non-equilibrium. We emphasize that in non-equilibrium case, the resulting relic density is very small. While with equilibrium, it is increased by a factor of O(102) with respect to the standard thermal production. Therefore, dark matter particles with large cross section, which is favored by detection expirements, can be consistent with the recent relic density observational limits

  8. Clinical research monitoring: scenarios and challenges

    Directory of Open Access Journals (Sweden)

    Gustavo Adolfo Sierra Romero

    2013-01-01

    Full Text Available Clinical research is essential for the development of new drugs, diagnostic tests and new devices. Clinical monitoring is implemented to improve the quality of research and attain high ethical and scientific standards. This review discusses the role of clinical monitors, taking into account the variety of scenarios in which medical research is developed, and highlights the challenges faced by research teams to ensure that patients rights are respected and that the social role of scientific research is preserved. Specific emphasis is given to the ethical dilemmas related to the multiple roles which clinical monitors play in the research framework, mainly those involving the delicate equilibrium between the loyalty to the sponsor and to the research subjects. The essential role of clinical monitoring for research developed in poor healthcare scenarios is highlighted as an approach to get the local infrastructure strengthening needed to achieve an adequate level of good clinical practices.

  9. Selecting reasonable future land use scenarios

    International Nuclear Information System (INIS)

    This paper examines a process to help select the most reasonable future land use scenario for hazardous waste and/or low-level radioactive waste disposal sites. The process involves evaluating future land use scenarios ab applying selected criteria currently used by commercial mortgage companies to determine the feasibility of obtaining a loan for purchasing such land. The basis for the process is that only land use activities for which a loan can be obtained well be considered. To examine the process, a low-level radioactive waste site, the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory, is used as an example. The authors suggest that the process is a very precise, comprehensive, and systematic approach for determining reasonable future use of land. Implementing such a process will help enhance the planning, decisionmaking, safe management, and cleanup of present and future disposal facilities

  10. TECHNOLOGICAL SCENARIOS TO THE DEMAND FOR SUGARCANE

    Directory of Open Access Journals (Sweden)

    Ana Paula Franco Paes Leme Barbosa

    2012-06-01

    Full Text Available From the first decade of the 2000s, it is clear that there is an increase in discussions involving sustainability, including the bioenergy issue, to which Brazil has drawn the attention due to advances in the ethanol industry. Advances in engine technology reflected new opportunities for this industry and, according to the Ten-Year Energy Plan for 2019 developed by the Ministry of Mines and Energy, there is an expected increase in demand for ethanol of 90% by 2019 (Brazil, 2010. However, new technologies for the conversion and use of sugarcane and the complex context of this industry add uncertainties to this sector. Aiming to discuss and include the uncertainties on the agenda of this industry, this study proposes to elaborate and discuss prospective scenarios to the demand for sugarcane. Four scenarios with different perspectives of technological advance and market development were elaborated and discussed in the conclusion.

  11. Curvaton scenarios with inflaton decays into curvatons

    CERN Document Server

    Byrnes, Christian T; Liddle, Andrew R

    2016-01-01

    We consider the possible decay of the inflaton into curvaton particles during reheating and analyse its effect on curvaton scenarios. Typical decay curvatons are initially relativistic then become non-relativistic, and change the background history of the Universe. We show that this change to the background is the only way in which observational predictions of the scenario are modified. Moreover, once the required amplitude of perturbations is fixed by observation there are no signatures of such decays in other cosmological observables. The decay curvatons can prevent the Universe from becoming dominated by the curvaton condensate, making it impossible to match observations in parts of parameter space. This constrains the branching ratio of the inflaton to curvaton to be less than of order $0.1$ typically. If the branching ratio is below about $10^{-4}$ it has negligible impact on the model parameter space and can be ignored.

  12. The hexagon hypothesis: Six disruptive scenarios.

    Science.gov (United States)

    Burtles, Jim

    2015-01-01

    This paper aims to bring a simple but effective and comprehensive approach to the development, delivery and monitoring of business continuity solutions. To ensure that the arguments and principles apply across the board, the paper sticks to basic underlying concepts rather than sophisticated interpretations. First, the paper explores what exactly people are defending themselves against. Secondly, the paper looks at how defences should be set up. Disruptive events tend to unfold in phases, each of which invites a particular style of protection, ranging from risk management through to business continuity to insurance cover. Their impact upon any business operation will fall into one of six basic scenarios. The hexagon hypothesis suggests that everyone should be prepared to deal with each of these six disruptive scenarios and it provides them with a useful benchmark for business continuity. PMID:26420396

  13. Land use scenarios for greater Copenhagen

    DEFF Research Database (Denmark)

    Fertner, Christian; Jørgensen, Gertrud; Nielsen, Thomas Alexander Sick

    2012-01-01

    Urban planning and development in Denmark can be characterised by a relatively strong planning framework. Land use scenarios based on empirically derived dynamics of urban growth are practically never applied. However, modelling approaches do offer a methodology to explore the pressures in an urban...... region, as well as an approach to understand urban development patterns outside the ‘spatial masterplan’. In this context we will present the results of a modelling exercise addressing future land use change in the metropolitan area of Copenhagen, Denmark, and the impact of the current regional planning...... framework, the “Fingerplan 2007”. We test three policy scenarios and analyse different effects on urban growth by using the Metronamica model from the Dutch-based Research Institute for Knowledge Systems (RIKS). We analyse the possibilities to elaborate a practical and useful outcome within a relatively...

  14. Scenario Crisis Cases in Distance Learning Sessions

    Science.gov (United States)

    Antunes, A.

    2013-04-01

    We discuss early results using student-lead role-play of crises and disaster scenarios to encourage engagement in distance learning sessions. The disadvantage of distance learning via web interface—the lack of face-to-face and the ease with which a student can remain quiet—is balanced by the wealth of Internet-accessible media reports of past mission disasters. Capitol College minimizes the lecture component to simply frame each session's open-ended crisis in our Mission Operations engineering course. The students are presented with a historical ‘disaster’ but not its resolution; they present their course of action, then the lecturer steps in to debrief. With a wealth of past cases available on the web, use of scenarios rather than lectures shows early signs of being viable model for encouraging discussion and interaction within distance learning for a variety of course topics.

  15. Scenario Development for Sustainable Food Consumption

    DEFF Research Database (Denmark)

    Reisch, Lucia; Farsang, Andrea; Jégou, Francois

    seasonal dependency due to global trade and storage and process technology. On the demand side, relatively high and stable incomes combined with low food prices have in-creased accessibility, availability and affordability of a highly diverse food supply. Yet, according to the FAO, total food production...... will have to increase by up to 70% in order to feed the growing population projected to be around 9 billion people by 2050 with the largest increase in low-income countries. It will be a huge challenge for agriculture to meet this growing demand in a sustainable way. Besides global population increase...... brokerage. Scenarios can reveal uncertainties, can help prepare for unexpected changes and highlight crucial decisions to be taken today. Scenarios can offer a clearer picture of the present and visions for the future, can help to identify key driving forces and their trends as well as as-sess potential...

  16. River multimodal scenario for rehabilitation robotics.

    Science.gov (United States)

    Munih, Marko; Novak, Domen; Milavec, Maja; Ziherl, Jaka; Olenšek, Andrej; Mihelj, Matjaž

    2011-01-01

    This paper presents the novel "River" multimodal rehabilitation robotics scenario that includes video, audio and haptic modalities. Elements contributing to intrinsic motivation are carefully joined in the three modalities to increase motivation of the user. The user first needs to perform a motor action, then receives a cognitive challenge that is solved with adequate motor activity. Audio includes environmental sounds, music and spoken instructions or encouraging statements. Sounds and music were classified according to the arousal-valence space. The haptic modality can provide catching, grasping, tunnel or adaptive assistance, all depending on the user's needs. The scenario was evaluated in 16 stroke users, who responded to it favourably according to the Intrinsic Motivation Inventory questionnaire. Additionally, the river multimodal environment seems to elicit higher motivation than a simpler apple pick-and-place multimodal task. PMID:22275619

  17. Arctic shipping emissions inventories and future scenarios

    OpenAIRE

    J. J. Corbett; D. A. Lack; J. J. Winebrake; Harder, S; J. A. Silberman; Gold, M.

    2010-01-01

    This paper presents 5 km×5 km Arctic emissions inventories of important greenhouse gases, black carbon and other pollutants under existing and future (2050) scenarios that account for growth of shipping in the region, potential diversion traffic through emerging routes, and possible emissions control measures. These high-resolution, geospatial emissions inventories for shipping can be used to evaluate Arctic climate sensitivity to black carbon (a short-lived climate forcing pollutant especial...

  18. Clinical Scenarios for Discordant Anti-Xa

    OpenAIRE

    Jesus Vera-Aguilera; Hindi Yousef; Diego Beltran-Melgarejo; Teng Hugh Teng; Ramos Jan; Mary Mok; Carlos Vera-Aguilera; Eduardo Moreno-Aguilera

    2016-01-01

    Anti-Xa test measures the activity of heparin against the activity of activated coagulation factor X; significant variability of anti-Xa levels in common clinical scenarios has been observed. Objective. To review the most common clinical settings in which anti-Xa results can be bias. Evidence Review. Guidelines and current literature search: we used PubMed, Medline, Embase, and MEDION, from 2000 to October 2013. Results. Anti-Xa test is widely used; however the assay underestimates heparin co...

  19. Future Scenario of Renewable Energy in India

    OpenAIRE

    Sandeep Kumar; Mohit Rathi; Aloy Palit; Puneet Nandrajog

    2012-01-01

    This paper presents a review about future scenario of renewable energy in India.Energy is a vital input for economic and social development of any country. With increasing industrialand agricultural activities in the country, the demand for energy is also rising. Solar, wind and biomassare accepted as dependable and widely available renewable sources of energy. To meet the energy requirement for such a fast growingeconomy, India will require an assured supply of 3–5 times more energy than the...

  20. Management strategies in hospitals: scenario planning

    OpenAIRE

    Ghanem, Mohamed; Schnoor, Jörg; Heyde, Christoph-Eckhard; Kuwatsch, Sandra; Bohn, Marco; Josten, Christoph

    2015-01-01

    Background: Instead of waiting for challenges to confront hospital management, doctors and managers should act in advance to optimize and sustain value-based health. This work highlights the importance of scenario planning in hospitals, proposes an elaborated definition of the stakeholders of a hospital and defines the influence factors to which hospitals are exposed to. Methodology: Based on literature analysis as well as on personal interviews with stakeholders we propose an elaborated defi...

  1. Orchestrating Learning Scenarios for the Borderless Classroom

    OpenAIRE

    TAN, ESTHER; Rusman, Ellen

    2016-01-01

    This part of the symposium focuses on the design of seamless learning experiences in a borderless classroom. There are two parts to this symposium. We start with unpacking various theoretical approaches that inform the instructional design of boundary-crossing learning scenarios, such as social learning theory, experiential learning, situated cognition and theory of play. We then identify critical design elements for connecting in-and-out of classroom learning experiences, such as learning th...

  2. Metagenomic Detection Methods in Biopreparedness Outbreak Scenarios

    DEFF Research Database (Denmark)

    Karlsson, Oskar Erik; Hansen, Trine; Knutsson, Rickard;

    2013-01-01

    of a clinical sample, creating a metagenome, in a single week of laboratory work. As new technologies emerge, their dissemination and capacity building must be facilitated, and criteria for use, as well as guidelines on how to report results, must be established. This article focuses on the use of metagenomics......, gaps in research, and future directions. Examples of metagenomic detection, as well as possible applications of the methods, are described in various biopreparedness outbreak scenarios....

  3. Investment scenarios for Chinese power plants

    International Nuclear Information System (INIS)

    An analysis is provided of returns for investment in power plants in China and India. Three sample investment scenarios are compared to illustrate the relative merits of each financing arrangement. The best returns would seem to be offered by a mix of debt and equity financing. The potential problem of gradual currency depreciation can be overcome by early cash payments. Foreign investment in China's power generation industry would be more readily forthcoming if easier access to debt finance were available. (UK)

  4. Project SAFE. Scenario and system analysis

    International Nuclear Information System (INIS)

    This report describes the scenario analysis conducted within the SAFE project, which has resulted in a qualitative description of the SFR disposal system. The scenario report generally documents and justifies the selected system description model, selected scenario initiating events and conditions, the general selection of the type of quantitative evaluation models to be used and the information flow between models. The development of a system description model is done by groups of experts through a series of documented meetings, utilising the Interaction Matrix methodology. This methodology involves a systematic identification of processes and interactions between these processes occurring in the system and documented expert judgements of the relevance of these processes and interactions for the evolution of the system. The SFR disposal system is described by three coupled matrices: one for the repository vaults, one for the geosphere and one for the biosphere. The contents of the matrices have been audited against different international lists of FEPs (Features, Events, Processes) in order to ensure that all FEPs that are relevant are considered in the matrices. These lists of FEPs as well as experiences from past and recent SKB assessments have also been used in the selection of scenario initiating events and conditions. The system description in terms of interaction matrices cannot directly be used in the quantitative assessment. However, the system description can be used to point out the important interactions and how they should be treated in the quantitative analyses and to check that this is done. For this purpose an information flow diagram has been used. This diagram graphically displays the information exchange between the different analyses selected for the quantitative assessment of the evolution of the disposal system

  5. European Water Footprint Scenarios for 2050

    OpenAIRE

    A. Ertug Ercin; Arjen Y. Hoekstra

    2016-01-01

    This study develops water footprint scenarios for Europe for 2050, at the country level, based on projections regarding population and economic growth, production and trade patterns, consumption patterns (diets and bioenergy use) and technological development. The objective is to estimate possible future changes in the green, blue and grey water footprint (WF) of production and consumption, to analyze the main drivers of projected changes and to assess Europe’s future dependence on water reso...

  6. Designing Learning Scenarios for Sustainable Futures

    OpenAIRE

    Jones, Hannah; Lundebye, Anette

    2015-01-01

    Abstract: Understanding sustainability in terms of our complex, dynamic and interconnected socio-ecological systems requires a different mindset or paradigm to the industrial mode of thinking that has influenced educational practice for the last century (Orr, 2004, Wood, 2007). Our ambitious 3-hour workshop will focus on developing scenarios as a way to prospect how design education might respond to a range of possible ecological futures at a systemic level. Method: We will use metadesign...

  7. A Scenario of Rainfall Erosivity Index Research

    OpenAIRE

    D .V. Pandit1; R. K. Isaac2

    2015-01-01

    Rainfall erosivity index is an important index to evaluate the soil loss due to rainfall. Rainstorm plays a paramount role in surface sealing, runoff and erosion process. Research on rainfall erosivity index is important in understanding the mechanism of soil erosion processes. This paper gives a scenario on the important research work done by the scientists to evaluate the erosivity index by using various methods and approaches. The aim of this paper was also to highl...

  8. A tilted cold dark matter cosmological scenario

    Science.gov (United States)

    Cen, Renyue; Gnedin, Nickolay Y.; Kofman, Lev A.; Ostriker, Jeremiah P.

    1992-01-01

    A new cosmological scenario based on CDM but with a power spectrum index of about 0.7-0.8 is suggested. This model is predicted by various inflationary models with no fine tuning. This tilted CDM model, if normalized to COBE, alleviates many problems of the standard CDM model related to both small-scale and large-scale power. A physical bias of galaxies over dark matter of about two is required to fit spatial observations.

  9. Contingency Manager for Icarus Simulated Integrated Scenario

    OpenAIRE

    Rodriguez Carvajal, Juan-Jose; Caro Ignacio, Oriol

    2010-01-01

    Contingency analysis and reaction is a critical task to be carried out by any airplane to guarantee its safe operation in a non-segregated airspace. Pilot's reactions to any kind of incidences that may occur in-flight, like engine malfunctions, loss of electrical power, hydraulic failure, unexpected weather, etc, will determine the fate of the flight. Nowadays, contingency reactions are mainly driven by the airplane manufacturer, with pre-analyzed contingency scenarios covered in the airplane...

  10. Banking Stress Scenarios for Public Debt Projections

    OpenAIRE

    BENCZUR PETER; BERTI Katia; CARIBONI Jessica; DI GIROLAMO FRANCESCA; Langedijk, Sven; PAGANO Andrea; PETRACCO GIUDICI Marco

    2015-01-01

    The latest economic and financial crisis has shown how quickly vulnerabilities on the financial side of the economy can turn into a strong deterioration of public accounts, thus highlighting the importance to monitor fiscal risks arising outside the realm of public finances. This is particularly the case for the building up of risks in the banking sector, due to its central role in financial stability. In this spirit, this paper presents banking stress-test scenarios for public debt projectio...

  11. Healthy Air Outdoors

    Science.gov (United States)

    ... lung.org > Our Initiatives > Healthy Air > Outdoor Healthy Air Outdoors The quality of the air we breathe ... families and can even shorten their lives. Outdoor Air Pollution and Health Outdoor air pollution continues to ...

  12. Air quality

    International Nuclear Information System (INIS)

    This chapter of the 'Assessment of the state of the environment in Lebanon' describes the air quality and identifies the most important air quality issues. Baseline information about the factors affecting dispersion and the climate of Lebanon presents as well and overall estimation of total emissions in Lebanon. Emissions from vehicles, electricity and power plants generation are described. Industrial emitters of air pollutants are described for each kind of industry i.e.cement plants, Selaata fertilizer factory, sugar-beet factory, refineries and for those derived from the use of leaded fuel . Impact of economic and human activities on air quality in Lebanon (especially in Beirut and Tripoli) are quantified by quantities of CO2, SO2, NOx, total suspended particulates(TSP), deposition and their environmental effects on health. In abscence of emissions monitoring, data available are expressed in terms of fuel use, output and appropriate empirical factors, national output and workfores sizes. Finally key issues and some potential mitigation /management approaches are presented

  13. Clinical Scenarios for Discordant Anti-Xa

    Directory of Open Access Journals (Sweden)

    Jesus Vera-Aguilera

    2016-01-01

    Full Text Available Anti-Xa test measures the activity of heparin against the activity of activated coagulation factor X; significant variability of anti-Xa levels in common clinical scenarios has been observed. Objective. To review the most common clinical settings in which anti-Xa results can be bias. Evidence Review. Guidelines and current literature search: we used PubMed, Medline, Embase, and MEDION, from 2000 to October 2013. Results. Anti-Xa test is widely used; however the assay underestimates heparin concentration in the presence of significant AT deficiency, pregnancy, end stage renal disease, and postthrombolysis and in patients with hyperbilirubinemia; limited published data evaluating the safety and effectiveness of anti-Xa assays for managing UH therapy is available. Conclusions and Relevance. To our knowledge this is the first paper that summarizes the most common causes in which this assay can be affected, several “day to day” clinical scenarios can modify the outcomes, and we concur that these rarely recognized scenarios can be affected by negative outcomes in the daily practice.

  14. The development of climatic scenarios for Finland

    Energy Technology Data Exchange (ETDEWEB)

    Carter, T.; Tuomenvirta, H. [Finnish Meteorological Inst., Helsinki (Finland); Posch, M. [National Inst. of Public Health and the Environment, Bilthoven (Netherlands)

    1996-12-31

    One of the main objectives of the Finnish Research Programme on Climate Change (SILMU) has been to assess the possible impacts of future changes in climate due to the enhanced greenhouse effect on natural systems and human activities in Finland. In order to address this objective, it was first necessary to specify the types of climate changes to be expected in the Finnish region. Estimates of future climate are conventionally obtained using numerical models, which simulate the evolution of the future climate in response to radiative forcing due to changes in the composition of the atmosphere (i.e. of greenhouse gases and aerosols). However, there are large uncertainties in the model estimates because current knowledge and understanding of atmospheric processes remains incomplete. Since accurate predictions of climate change are not available, an alternative approach is to develop scenarios. These are plausible projections which reflect the best estimates to the future conditions but at the same time embrace the likely uncertainties attached to these estimates. In order to obtain expert opinion on the most appropriate methods of providing scenarios for SILMU, an International Workshop was organised in 1993. The recommendations of the Workshop formed the basis of the present project, initiated in 1994, to develop standard climatic scenarios for Finland

  15. The negaWatt scenario 2011

    International Nuclear Information System (INIS)

    Based on the development of energetic sobriety, energy efficiency and the use of renewable energies, and after having stressed the urgency of an energetic transition, the authors propose a scenario for the 2012-2050 period which integrates social and environmental criteria, uses realistic and mature solutions regarding technological choices, takes not only the struggle against climate change but also constraints water, raw materials and soil use into account. They analyse, sector per sector, the expected gains of a systematic application of a sobriety and efficiency strategy. It appears that the building is the main energetic stake, that transports have to be considered on a long term, that industry will have to evolve as well as the agriculture sector. The scenario notably comprises an actual lift off for renewable energies, a marginal use of fossil energies, a progressive withdrawal from nuclear, and the development of a complementarity between networks. This could lead to 100 pc sustainable primary energy. The authors show that such a scenario complies with the world energy and climate challenges by 2050. They discuss the cost of such a transition and propose several actions

  16. Clinical Scenarios for Discordant Anti-Xa

    Science.gov (United States)

    Vera-Aguilera, Jesus; Yousef, Hindi; Beltran-Melgarejo, Diego; Teng, Teng Hugh; Jan, Ramos; Mok, Mary; Vera-Aguilera, Carlos; Moreno-Aguilera, Eduardo

    2016-01-01

    Anti-Xa test measures the activity of heparin against the activity of activated coagulation factor X; significant variability of anti-Xa levels in common clinical scenarios has been observed. Objective. To review the most common clinical settings in which anti-Xa results can be bias. Evidence Review. Guidelines and current literature search: we used PubMed, Medline, Embase, and MEDION, from 2000 to October 2013. Results. Anti-Xa test is widely used; however the assay underestimates heparin concentration in the presence of significant AT deficiency, pregnancy, end stage renal disease, and postthrombolysis and in patients with hyperbilirubinemia; limited published data evaluating the safety and effectiveness of anti-Xa assays for managing UH therapy is available. Conclusions and Relevance. To our knowledge this is the first paper that summarizes the most common causes in which this assay can be affected, several “day to day” clinical scenarios can modify the outcomes, and we concur that these rarely recognized scenarios can be affected by negative outcomes in the daily practice. PMID:27293440

  17. Management strategies in hospitals: scenario planning

    Directory of Open Access Journals (Sweden)

    Ghanem, Mohamed

    2015-06-01

    Full Text Available Background: Instead of waiting for challenges to confront hospital management, doctors and managers should act in advance to optimize and sustain value-based health. This work highlights the importance of scenario planning in hospitals, proposes an elaborated definition of the stakeholders of a hospital and defines the influence factors to which hospitals are exposed to. Methodology: Based on literature analysis as well as on personal interviews with stakeholders we propose an elaborated definition of stakeholders and designed a questionnaire that integrated the following influence factors, which have relevant impact on hospital management: political/legal, economic, social, technological and environmental forces. These influence factors are examined to develop the so-called critical uncertainties. Thorough identification of uncertainties was based on a “Stakeholder Feedback”. Results: Two key uncertainties were identified and considered in this study: According to the developed scenarios, complementary education of the medical staff as well as of non-medical top executives and managers of hospitals was the recommended core strategy. Complementary scenario-specific strategic options should be considered whenever needed to optimize dealing with a specific future development of the health care environment. Conclusion: Strategic planning in hospitals is essential to ensure sustainable success. It considers multiple situations and integrates internal and external insights and perspectives in addition to identifying weak signals and “blind spots”. This flows into a sound planning for multiple strategic options. It is a state of the art tool that allows dealing with the increasing challenges facing hospital management.

  18. Low carbon society scenario analysis of transport sector of an emerging economy—The AIM/Enduse modelling approach

    International Nuclear Information System (INIS)

    The transport sector of a country is the backbone driving the economy forward. Thailand’s land transport sector is modelled using the AIM/Enduse, which is a recursive dynamic optimization model, based on bottom-up modelling principle. The travel demand is divided into two major categories which are passenger travel and freight travel. The objective of this paper is to analyse the mitigation possible through low carbon society (LCS) measures and emission tax (ET). Two scenario clusters are devised along with the BAU case. The LCS scenario cluster has three designed scenarios which are LCS-L, LCS-M and LCS-H. The emission tax (ET) cluster has four scenarios, where the taxes of 50, 100, 200 and 500 USD/t-CO2 are implemented. Along with this the marginal abatement costs (MAC) of the counter-measures (CMs) and the co-benefits in terms of energy security, productivity and air pollutant mitigation are also assessed. Results show that LCS scenarios are possible of mitigating up to 1230 Mt-CO2 cumulatively, from 2010 to 2050. In terms of MACs, new vehicles play a pivotal role, along with hybrid vehicles. The Average Abatement Cost (AAC) assessment shows that the AAC of LCS-H scenario is in the order of 100 USD/t-CO2. All the LCS and ET scenarios show an enhancement in energy security and also a threefold increase in productivity. There is distinct mitigation in terms of air pollutants from the transport sector as well. -- Highlights: •Thailand transport sector has been modelled using AIM/Enduse model. •Potential cumulative mitigation of CO2 during 2010–2050 is approximately 30% when compared the BAU scenario. •Abatement cost curves show that various counter measures are practical in the transport sector. •Energy security is enhanced due to CO2 mitigation in the LCS scenario

  19. Deforestation scenarios for the Bolivian lowlands.

    Science.gov (United States)

    Tejada, Graciela; Dalla-Nora, Eloi; Cordoba, Diana; Lafortezza, Raffaele; Ovando, Alex; Assis, Talita; Aguiar, Ana Paula

    2016-01-01

    Tropical forests in South America play a key role in the provision of ecosystem services such as carbon sinks, biodiversity conservation, and global climate regulation. In previous decades, Bolivian forests have mainly been deforested by the expansion of agricultural frontier development, driven by the growing demands for beef and other productions. In the mid-2000s the Movimiento al Socialismo (MAS) party rose to power in Bolivia with the promise of promoting an alternative development model that would respect the environment. The party passed the world's first laws granting rights to the environment, which they termed Mother Earth (Law No. 300 of 2012), and proposed an innovative framework that was expected to develop radical new conservation policies. The MAS conservationist discourse, policies, and productive practices, however, have since been in permanent tension. The government continues to guarantee food production through neo-extractivist methods by promoting the notion to expand agriculture from 3 to 13 million ha, risking the tropical forests and their ecosystem services. These actions raise major environmental and social concerns, as the potential impacts of such interventions are still unknown. The objective of this study is to explore an innovative land use modeling approach to simulate how the growing demand for land could affect future deforestation trends in Bolivia. We use the LuccME framework to create a spatially-explicit land cover change model and run it under three different deforestation scenarios, spanning from the present-2050. In the Sustainability scenario, deforestation reaches 17,703,786 ha, notably in previously deforested or degraded areas, while leaving forest extensions intact. In the Middle of the road scenario, deforestation and degradation move toward new or paved roads spreading across 25,698,327 ha in 2050, while intact forests are located in Protected Areas (PAs). In the Fragmentation scenario, deforestation expands to almost

  20. Global emissions of mercury to the atmosphere in 2005 and their 2020 scenarios

    Science.gov (United States)

    Pacyna, Jozef M.; Pacyna, Elisabeth G.; Sundseth, Kyrre; Munthe, John; Wilson, Simon; Leaner, Joy

    2010-05-01

    About the three quarters of the total anthropogenic emissions of mercury in the year 2005 estimated to be 1930 tonnes comes from sources where mercury is emitted as a by-product, and the rest is emitted during various applications of mercury. The largest emissions of Hg to the global atmosphere occur from combustion of fossil fuels, mainly coal in utility, industrial, and residential boilers (almost 47 %), followed by artisanal mining (almost 17 %), non-ferrous metal production, including gold production (13.5%) and cement production (about 9.5 %). Doing nothing for the improvement of the Hg emission reductions (so-called Status Quo - SQ scenario) will cause an increase of the emissions in 2020 by almost 100 % compared to the 2020 Extended Emission Control (EXEC) emission reduction scenario. Even larger increase is estimated when the 2020 SQ scenario of Hg emissions is compared with the 2020 Maximum Feasible Technical Reduction (MFTR) emission reduction scenario. The EXEC scenario assumes economic progress at a rate dependent on the future development of industrial technologies and emission control technologies, i.e. mercury-reducing technology currently generally employed throughout Europe and North America would be implemented elsewhere. It further assumes that emissions control measures currently implemented or committed to in Europe to reduce mercury emission to air or water would be implemented around the world. The MFTR scenario assumes implementation of all solutions/ measures leading to the maximum degree of reduction of mercury emissions and its loads discharged to any environment; cost is taken into account but only as a secondary consideration. Emissions of Hg in various industrial sectors, such as cement production and metal manufacturing in the year 2020 can be 2 to 3 times larger if nothing will be done to improve emission control in comparison with the EXEC scenario.