WorldWideScience

Sample records for collaborative fire modeling

  1. International collaborative fire modeling project (ICFMP). Summary of benchmark

    International Nuclear Information System (INIS)

    Roewekamp, Marina; Klein-Hessling, Walter; Dreisbach, Jason; McGrattan, Kevin; Miles, Stewart; Plys, Martin; Riese, Olaf

    2008-09-01

    This document was developed in the frame of the 'International Collaborative Project to Evaluate Fire Models for Nuclear Power Plant Applications' (ICFMP). The objective of this collaborative project is to share the knowledge and resources of various organizations to evaluate and improve the state of the art of fire models for use in nuclear power plant fire safety, fire hazard analysis and fire risk assessment. The project is divided into two phases. The objective of the first phase is to evaluate the capabilities of current fire models for fire safety analysis in nuclear power plants. The second phase will extend the validation database of those models and implement beneficial improvements to the models that are identified in the first phase of ICFMP. In the first phase, more than 20 expert institutions from six countries were represented in the collaborative project. This Summary Report gives an overview on the results of the first phase of the international collaborative project. The main objective of the project was to evaluate the capability of fire models to analyze a variety of fire scenarios typical for nuclear power plants (NPP). The evaluation of the capability of fire models to analyze these scenarios was conducted through a series of in total five international Benchmark Exercises. Different types of models were used by the participating expert institutions from five countries. The technical information that will be useful for fire model users, developers and further experts is summarized in this document. More detailed information is provided in the corresponding technical reference documents for the ICFMP Benchmark Exercises No. 1 to 5. The objective of these exercises was not to compare the capabilities and strengths of specific models, address issues specific to a model, nor to recommend specific models over others. This document is not intended to provide guidance to users of fire models. Guidance on the use of fire models is currently being

  2. Performing of recent real scale cable fire experiments and presentation of the results in the frame of the international collaborative fire modeling project ICFMP. Final report

    International Nuclear Information System (INIS)

    Hosser, Dietmar; Riese, Olaf; Klingenberg, Mark

    2005-01-01

    As a part of the Fire Risk Research Program, the German iBMB (Institut fuer Baustoffe, Massivbau und Brandschutz) of Braunschweig University of Technology and GRS (Gesellschaft fuer Anlagenund Reaktorsicherheit mbH) are participating in an International Collaborative Fire Modeling Project (ICFMP) to assess and validate fire computer codes for nuclear power plant applications. This assessment is being conducted through benchmarking and validation exercises. The tests are simulating cable fires scenarios in a single compartment. The goal of the actual cable fire series is to investigate the effects of a natural fire to vertically routed cables (worst case) with different cable insulation material (PVC and FRNC). Another important aspect of cable fire is the risk of function failure. Therefore in the test series the short circuit and the conduction loss of cables are measured. This report includes a first description of the experimental results for test 1 - test 4 of the International Collaborative Fire Model Project conducted in December 2003 at the iBMB in Germany. The experimental data are reported on the International Collaborative Fire Model Project - Platform. The measured data shall be the basis for fire simulations. The tests show that the FRNC cables have significantly better characteristics in case of fire. No substantial flame spread takes place even in case of preheating. PVC cables could be ignited with a burner output of 50 kW, in contrary, the FRNC cables could be ignited at burner output of 150 kW. The preheating has a complex effect on the fire behavior of the cables. It may occur that gases are pyrolysed which are not ignited during the phase of preheating. These gases are transported from the cable surrounding and may leave the fire room. Short circuits occur first in case ''conductor to conductor'' and later in case ''conductor to tray''. The time periods until short circuits occur are strongly dependent on the preheating of the cables. In case of

  3. Forest-fire models

    Science.gov (United States)

    Haiganoush Preisler; Alan Ager

    2013-01-01

    For applied mathematicians forest fire models refer mainly to a non-linear dynamic system often used to simulate spread of fire. For forest managers forest fire models may pertain to any of the three phases of fire management: prefire planning (fire risk models), fire suppression (fire behavior models), and postfire evaluation (fire effects and economic models). In...

  4. Collaborative networks: Reference modeling

    NARCIS (Netherlands)

    Camarinha-Matos, L.M.; Afsarmanesh, H.

    2008-01-01

    Collaborative Networks: Reference Modeling works to establish a theoretical foundation for Collaborative Networks. Particular emphasis is put on modeling multiple facets of collaborative networks and establishing a comprehensive modeling framework that captures and structures diverse perspectives of

  5. FIRE CHARACTERISTICS FOR ADVANCED MODELLING OF FIRES

    OpenAIRE

    Otto Dvořák

    2016-01-01

    This paper summarizes the material and fire properties of solid flammable/combustible materials /substances /products, which are used as inputs for the computer numerical fire models. At the same time it gives the test standards for their determination.

  6. Modeling of compartment fire

    International Nuclear Information System (INIS)

    Sathiah, P.; Siccama, A.; Visser, D.; Komen, E.

    2011-01-01

    Fire accident in a containment is a serious threat to nuclear reactors. Fire can cause substantial loss to life and property. The risk posed by fire can also exceed the risk from internal events within a nuclear reactor. Numerous research efforts have been performed to understand and analyze the phenomenon of fire in nuclear reactor and its consequences. Modeling of fire is an important subject in the field of fire safety engineering. Two approaches which are commonly used in fire modeling are zonal modeling and field modeling. The objective of this work is to compare zonal and field modeling approach against a pool fired experiment performed in a well-confined compartment. Numerical simulations were performed against experiments, which were conducted within PRISME program under the framework of OECD. In these experiments, effects of ventilation flow rate on heat release rate in a confined and mechanically ventilated compartment is investigated. Time dependent changes in gas temperature and oxygen mass fraction were measured. The trends obtained by numerical simulation performed using zonal model and field model compares well with experiments. Further validation is needed before this code can be used for fire safety analyses. (author)

  7. Modeling urban fire growth

    International Nuclear Information System (INIS)

    Waterman, T.E.; Takata, A.N.

    1983-01-01

    The IITRI Urban Fire Spread Model as well as others of similar vintage were constrained by computer size and running costs such that many approximations/generalizations were introduced to reduce program complexity and data storage requirements. Simplifications were introduced both in input data and in fire growth and spread calculations. Modern computational capabilities offer the means to introduce greater detail and to examine its practical significance on urban fire predictions. Selected portions of the model are described as presently configured, and potential modifications are discussed. A single tract model is hypothesized which permits the importance of various model details to be assessed, and, other model applications are identified

  8. Fire Models and Design Fires

    DEFF Research Database (Denmark)

    Poulsen, Annemarie

    The aim of this project is to perform an experimental study on the influence of the thermal feedback on the burning behavior of well ventilated pre-flashover fires. For the purpose an experimental method has been developed. Here the same identical objects are tested under free burn conditions...... carried out by Carleton University and NRC-IRC performed on seven different types of fire loads representing commercial premises, comprise the tests used for the study. The results show that for some of the room test the heat release rate increased due to thermal feedback compared to free burn for a pre......-flashover fire. Two phenomena were observed, that relate well to theory was found. In an incipient phase the heat release rate rose with the temperature of the smoke layer/enclosure boundaries. This increase was also found to depend on the flammability properties of the burning object. The results also...

  9. FIRE CHARACTERISTICS FOR ADVANCED MODELLING OF FIRES

    Directory of Open Access Journals (Sweden)

    Otto Dvořák

    2016-07-01

    Full Text Available This paper summarizes the material and fire properties of solid flammable/combustible materials /substances /products, which are used as inputs for the computer numerical fire models. At the same time it gives the test standards for their determination.

  10. Managing wildland fires: integrating weather models into fire projections

    Science.gov (United States)

    Anne M. Rosenthal; Francis Fujioka

    2004-01-01

    Flames from the Old Fire sweep through lands north of San Bernardino during late fall of 2003. Like many Southern California fires, the Old Fire consumed susceptible forests at the urban-wildland interface and spread to nearby city neighborhoods. By incorporating weather models into fire perimeter projections, scientist Francis Fujioka is improving fire modeling as a...

  11. Cinema Fire Modelling by FDS

    International Nuclear Information System (INIS)

    Glasa, J; Valasek, L; Weisenpacher, P; Halada, L

    2013-01-01

    Recent advances in computer fluid dynamics (CFD) and rapid increase of computational power of current computers have led to the development of CFD models capable to describe fire in complex geometries incorporating a wide variety of physical phenomena related to fire. In this paper, we demonstrate the use of Fire Dynamics Simulator (FDS) for cinema fire modelling. FDS is an advanced CFD system intended for simulation of the fire and smoke spread and prediction of thermal flows, toxic substances concentrations and other relevant parameters of fire. The course of fire in a cinema hall is described focusing on related safety risks. Fire properties of flammable materials used in the simulation were determined by laboratory measurements and validated by fire tests and computer simulations

  12. Cinema Fire Modelling by FDS

    Science.gov (United States)

    Glasa, J.; Valasek, L.; Weisenpacher, P.; Halada, L.

    2013-02-01

    Recent advances in computer fluid dynamics (CFD) and rapid increase of computational power of current computers have led to the development of CFD models capable to describe fire in complex geometries incorporating a wide variety of physical phenomena related to fire. In this paper, we demonstrate the use of Fire Dynamics Simulator (FDS) for cinema fire modelling. FDS is an advanced CFD system intended for simulation of the fire and smoke spread and prediction of thermal flows, toxic substances concentrations and other relevant parameters of fire. The course of fire in a cinema hall is described focusing on related safety risks. Fire properties of flammable materials used in the simulation were determined by laboratory measurements and validated by fire tests and computer simulations

  13. Rx-CADRE (Prescribed Fire Combustion-Atmospheric Dynamics Research Experiments) collaborative research in the core fire sciences

    Science.gov (United States)

    D. Jimenez; B. Butler; K. Hiers; R. Ottmar; M. Dickinson; R. Kremens; J. O' Brien; A. Hudak; C. Clements

    2009-01-01

    The Rx-CADRE project was the combination of local and national fire expertise in the field of core fire research. The project brought together approximately 30 fire scientists from six geographic regions and seven diff erent agencies. The project objectives were to demonstrate the capacity for collaborative research by bringing together individuals and teams with a...

  14. SNL/JAEA Collaborations on Sodium Fire Benchmarking.

    Energy Technology Data Exchange (ETDEWEB)

    Clark, Andrew Jordan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Denman, Matthew R [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Takata, Takashi [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ohshima, Hiroyuki [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-11-01

    Two sodium spray fire experiments performed by Sandia National Laboratories (SNL) were used for a code - to - code comparison between CONTAIN - LMR and SPHINCS. Both computer codes are used for modeling sodium accidents in sodium fast reactors. The comparison between the two codes provides insights into the ability of both codes to model sodium spray fires. The SNL T3 and T4 experiments are 20 kg sodium spray fires with sodium spray temperature s of 200 deg C and 500 deg C, respe ctively. Given the relatively low sodium temperature in the SNL T3 experiment, the sodium spray experienced a period of non - combustion. The vessel in the SNL T4 experiment experienced a rapid pressurization that caused of the instrumentation ports to fail during the sodium spray. Despite these unforeseen difficulties, both codes were shown in good agreement with the experiment s . The subsequent pool fire that develops from the unburned sodium spray is a significant characteristic of the T3 experiment. SPHIN CS showed better long - term agreement with the SNL T3 experiment than CONTAIN - LMR. The unexpected port failure during the SNL T4 experiment presented modelling challenges. The time at which the port failure occurred is unknown, but is believed to have occur red at about 11 seconds into the sodium spray fire. The sensitivity analysis for the SNL T4 experiment shows that with a port failure, the sodium spray fire can still maintain elevated pressures during the spray.

  15. 2013 Annual Report: Fire Modeling Institute

    Science.gov (United States)

    Robin J. Innes; Faith Ann Heinsch; Kristine M. Lee

    2014-01-01

    The Fire Modeling Institute (FMI) of the U.S. Forest Service, Rocky Mountain Research Station (RMRS), is a national and international resource for fire managers. Located within the Fire, Fuel, and Smoke Science Program at the Missoula Fire Sciences Laboratory (Fire Lab) in Montana, FMI helps managers utilize fire and fuel science and technology developed throughout the...

  16. Model of large pool fires

    Energy Technology Data Exchange (ETDEWEB)

    Fay, J.A. [Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)]. E-mail: jfay@mit.edu

    2006-08-21

    A two zone entrainment model of pool fires is proposed to depict the fluid flow and flame properties of the fire. Consisting of combustion and plume zones, it provides a consistent scheme for developing non-dimensional scaling parameters for correlating and extrapolating pool fire visible flame length, flame tilt, surface emissive power, and fuel evaporation rate. The model is extended to include grey gas thermal radiation from soot particles in the flame zone, accounting for emission and absorption in both optically thin and thick regions. A model of convective heat transfer from the combustion zone to the liquid fuel pool, and from a water substrate to cryogenic fuel pools spreading on water, provides evaporation rates for both adiabatic and non-adiabatic fires. The model is tested against field measurements of large scale pool fires, principally of LNG, and is generally in agreement with experimental values of all variables.

  17. Model of large pool fires

    International Nuclear Information System (INIS)

    Fay, J.A.

    2006-01-01

    A two zone entrainment model of pool fires is proposed to depict the fluid flow and flame properties of the fire. Consisting of combustion and plume zones, it provides a consistent scheme for developing non-dimensional scaling parameters for correlating and extrapolating pool fire visible flame length, flame tilt, surface emissive power, and fuel evaporation rate. The model is extended to include grey gas thermal radiation from soot particles in the flame zone, accounting for emission and absorption in both optically thin and thick regions. A model of convective heat transfer from the combustion zone to the liquid fuel pool, and from a water substrate to cryogenic fuel pools spreading on water, provides evaporation rates for both adiabatic and non-adiabatic fires. The model is tested against field measurements of large scale pool fires, principally of LNG, and is generally in agreement with experimental values of all variables

  18. Ventilation system in fire modelization

    International Nuclear Information System (INIS)

    Cordero Garcia, S.

    2012-01-01

    There is a model of fire in an enclosure formed by two rooms. In one of them, it will cause the fire and check how the system of ventilation in different configurations responds. In addition, the behavior of selected targets, which will be a configuration of cables similar to those found in nuclear power stations will be analyzed.

  19. Fire models for assessment of nuclear power plant fires

    International Nuclear Information System (INIS)

    Nicolette, V.F.; Nowlen, S.P.

    1989-01-01

    This paper reviews the state-of-the-art in available fire models for the assessment of nuclear power plants fires. The advantages and disadvantages of three basic types of fire models (zone, field, and control volume) and Sandia's experience with these models will be discussed. It is shown that the type of fire model selected to solve a particular problem should be based on the information that is required. Areas of concern which relate to all nuclear power plant fire models are identified. 17 refs., 6 figs

  20. Decision modeling for analyzing fire action outcomes

    Science.gov (United States)

    Donald MacGregor; Armando Gonzalez-Caban

    2008-01-01

    A methodology for incident decomposition and reconstruction is developed based on the concept of an "event-frame model." The event-frame model characterizes a fire incident in terms of (a) environmental events that pertain to the fire and the fire context (e.g., fire behavior, weather, fuels) and (b) management events that represent responses to the fire...

  1. Analytical model for cable tray fires

    International Nuclear Information System (INIS)

    Clarke, R.K.

    1975-09-01

    A model for cable tray fires based on buoyant plume theory is presented. Using the model in conjunction with empirical data on size of natural fires and burning rate of cellulosic materials, estimates are made of the heat flux as a function of vertical and horizontal distance from a tray fire. Both local fires and fires extending along a significant length of tray are considered. For the particular set of fire parameters assumed in the calculations, the current tray separation criteria of five feet vertical and three feet horizontal are found to be marginal for local fires and too small to prevent fire spread for extended tray fires. 8 references. (auth)

  2. Model of multiroom fire spread

    International Nuclear Information System (INIS)

    Tanaka, Takeyoshi.

    1983-01-01

    This paper presents a refined version of a mathematical model for predicting the hot gas flow induced by fires in multiroom structures. Two layer zone modeling approach is used in the mathematical formulation of the model. Some of the results of sample calculations of the model are also given for a couple of model structures

  3. Modelling Technology for Building Fire Scene with Virtual Geographic Environment

    Science.gov (United States)

    Song, Y.; Zhao, L.; Wei, M.; Zhang, H.; Liu, W.

    2017-09-01

    Building fire is a risky activity that can lead to disaster and massive destruction. The management and disposal of building fire has always attracted much interest from researchers. Integrated Virtual Geographic Environment (VGE) is a good choice for building fire safety management and emergency decisions, in which a more real and rich fire process can be computed and obtained dynamically, and the results of fire simulations and analyses can be much more accurate as well. To modelling building fire scene with VGE, the application requirements and modelling objective of building fire scene were analysed in this paper. Then, the four core elements of modelling building fire scene (the building space environment, the fire event, the indoor Fire Extinguishing System (FES) and the indoor crowd) were implemented, and the relationship between the elements was discussed also. Finally, with the theory and framework of VGE, the technology of building fire scene system with VGE was designed within the data environment, the model environment, the expression environment, and the collaborative environment as well. The functions and key techniques in each environment are also analysed, which may provide a reference for further development and other research on VGE.

  4. WRF-Fire: coupled weather-wildland fire modeling with the weather research and forecasting model

    Science.gov (United States)

    Janice L. Coen; Marques Cameron; John Michalakes; Edward G. Patton; Philip J. Riggan; Kara M. Yedinak

    2012-01-01

    A wildland fire behavior module (WRF-Fire) was integrated into the Weather Research and Forecasting (WRF) public domain numerical weather prediction model. The fire module is a surface fire behavior model that is two-way coupled with the atmospheric model. Near-surface winds from the atmospheric model are interpolated to a finer fire grid and used, with fuel properties...

  5. A hierarchical fire frequency model to simulate temporal patterns of fire regimes in LANDIS

    Science.gov (United States)

    Jian Yang; Hong S. He; Eric J. Gustafson

    2004-01-01

    Fire disturbance has important ecological effects in many forest landscapes. Existing statistically based approaches can be used to examine the effects of a fire regime on forest landscape dynamics. Most examples of statistically based fire models divide a fire occurrence into two stages--fire ignition and fire initiation. However, the exponential and Weibull fire-...

  6. Stochastic representation of fire behavior in a wildland fire protection planning model for California.

    Science.gov (United States)

    J. Keith Gilless; Jeremy S. Fried

    1998-01-01

    A fire behavior module was developed for the California Fire Economics Simulator version 2 (CFES2), a stochastic simulation model of initial attack on wildland fire used by the California Department of Forestry and Fire Protection. Fire rate of spread (ROS) and fire dispatch level (FDL) for simulated fires "occurring" on the same day are determined by making...

  7. Probability model for analyzing fire management alternatives: theory and structure

    Science.gov (United States)

    Frederick W. Bratten

    1982-01-01

    A theoretical probability model has been developed for analyzing program alternatives in fire management. It includes submodels or modules for predicting probabilities of fire behavior, fire occurrence, fire suppression, effects of fire on land resources, and financial effects of fire. Generalized "fire management situations" are used to represent actual fire...

  8. Fire Modeling Institute 2011 Annual Report

    Science.gov (United States)

    Robin J. Innes

    2012-01-01

    The Fire Modeling Institute (FMI), a part of the Rocky Mountain Research Station, Fire, Fuel, and Smoke Science Program, provides a bridge between scientists and managers. The mission of FMI is to bring the best available science and technology developed throughout the research community to bear on fire-related management issues across the nation. Resource management...

  9. Sensitivity Analysis on Fire Modeling of Main Control Board Fire Using Fire Dynamics Simulator

    International Nuclear Information System (INIS)

    Kang, Dae Il; Lim, Ho Gon

    2015-01-01

    In this study, sensitivity analyses for an MCB fire were performed to identify the effects on the MCR forced abandonment time according to the changes of height and number for fire initiation places. Hanul Unit 3 NPP was selected as a reference plant for this study. In this study, sensitivity analyses for an MCB fire were performed to identify the effects on the MCR forced abandonment time according to the changes of height and number of fire initiation places. A main control board (MCB) fire can cause a forced main control room (MCR) abandonment of the operators as well as the function failures or spurious operations of the control and instrumentation-related components. If the MCR cannot be habitable, a safe shutdown from outside the MCR can be achieved and maintained at an alternate shutdown panel independent from the MCR. When the fire modeling for an electrical cabinet such as an MCB was performed, its many input parameters can affect the fire simulation results. This study results showed that the decrease in the height of fire ignition place and the use of single fire ignition place in fire modeling for the propagating fire shortened MCR abandonment time

  10. Sensitivity Analysis on Fire Modeling of Main Control Board Fire Using Fire Dynamics Simulator

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Dae Il; Lim, Ho Gon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    In this study, sensitivity analyses for an MCB fire were performed to identify the effects on the MCR forced abandonment time according to the changes of height and number for fire initiation places. Hanul Unit 3 NPP was selected as a reference plant for this study. In this study, sensitivity analyses for an MCB fire were performed to identify the effects on the MCR forced abandonment time according to the changes of height and number of fire initiation places. A main control board (MCB) fire can cause a forced main control room (MCR) abandonment of the operators as well as the function failures or spurious operations of the control and instrumentation-related components. If the MCR cannot be habitable, a safe shutdown from outside the MCR can be achieved and maintained at an alternate shutdown panel independent from the MCR. When the fire modeling for an electrical cabinet such as an MCB was performed, its many input parameters can affect the fire simulation results. This study results showed that the decrease in the height of fire ignition place and the use of single fire ignition place in fire modeling for the propagating fire shortened MCR abandonment time.

  11. Fire in the Earth System: Bridging data and modeling research

    Science.gov (United States)

    Hantson, Srijn; Kloster, Silvia; Coughlan, Michael; Daniau, Anne-Laure; Vanniere, Boris; Bruecher, Tim; Kehrwald, Natalie; Magi, Brian I.

    2016-01-01

    Significant changes in wildfire occurrence, extent, and severity in areas such as western North America and Indonesia in 2015 have made the issue of fire increasingly salient in both the public and scientific spheres. Biomass combustion rapidly transforms land cover, smoke pours into the atmosphere, radiative heat from fires initiates dramatic pyrocumulus clouds, and the repeated ecological and atmospheric effects of fire can even impact regional and global climate. Furthermore, fires have a significant impact on human health, livelihoods, and social and economic systems.Modeling and databased methods to understand fire have rapidly coevolved over the past decade. Satellite and ground-based data about present-day fire are widely available for applications in research and fire management. Fire modeling has developed in part because of the evolution in vegetation and Earth system modeling efforts, but parameterizations and validation are largely focused on the present day because of the availability of satellite data. Charcoal deposits in sediment cores have emerged as a powerful method to evaluate trends in biomass burning extending back to the Last Glacial Maximum and beyond, and these records provide a context for present-day fire. The Global Charcoal Database version 3 compiled about 700 charcoal records and more than 1,000 records are expected for the future version 4. Together, these advances offer a pathway to explore how the strengths of fire data and fire modeling could address the weaknesses in the overall understanding of human-climate–fire linkages.A community of researchers studying fire in the Earth system with individual expertise that included paleoecology, paleoclimatology, modern ecology, archaeology, climate, and Earth system modeling, statistics, geography, biogeochemistry, and atmospheric science met at an intensive workshop in Massachusetts to explore new research directions and initiate new collaborations. Research themes, which emerged from

  12. Fire safety assessment for the fire areas of the nuclear power plant using fire model CFAST

    International Nuclear Information System (INIS)

    Lee, Yoon Hwan; Yang, Joon Eon; Kim, Jong Hoon

    2005-03-01

    Now the deterministic analysis results for the cable integrity is not given in case of performing the fire PSA. So it is necessary to develop the assessment methodology for the fire growth and propagation. This document is intended to analyze the peak temperature of the upper gas layer using the fire modeling code, CFAST, to evaluate the integrity of the cable located on the dominant pump rooms, and to assess the CCDP(Conditional Core Damage Probability) using the results of the cable integrity. According to the analysis results, the cable integrity of the pump rooms is maintained and CCDP is reduced about two times than the old one. Accordingly, the fire safety assessment for the dominant fire areas using the fire modeling code will capable to reduce the uncertainty and to develop a more realistic model

  13. Quantitative Risk Modeling of Fire on the International Space Station

    Science.gov (United States)

    Castillo, Theresa; Haught, Megan

    2014-01-01

    The International Space Station (ISS) Program has worked to prevent fire events and to mitigate their impacts should they occur. Hardware is designed to reduce sources of ignition, oxygen systems are designed to control leaking, flammable materials are prevented from flying to ISS whenever possible, the crew is trained in fire response, and fire response equipment improvements are sought out and funded. Fire prevention and mitigation are a top ISS Program priority - however, programmatic resources are limited; thus, risk trades are made to ensure an adequate level of safety is maintained onboard the ISS. In support of these risk trades, the ISS Probabilistic Risk Assessment (PRA) team has modeled the likelihood of fire occurring in the ISS pressurized cabin, a phenomenological event that has never before been probabilistically modeled in a microgravity environment. This paper will discuss the genesis of the ISS PRA fire model, its enhancement in collaboration with fire experts, and the results which have informed ISS programmatic decisions and will continue to be used throughout the life of the program.

  14. Performance of fire behavior fuel models developed for the Rothermel Surface Fire Spread Model

    Science.gov (United States)

    Robert Ziel; W. Matt Jolly

    2009-01-01

    In 2005, 40 new fire behavior fuel models were published for use with the Rothermel Surface Fire Spread Model. These new models are intended to augment the original 13 developed in 1972 and 1976. As a compiled set of quantitative fuel descriptions that serve as input to the Rothermel model, the selected fire behavior fuel model has always been critical to the resulting...

  15. Resolving vorticity-driven lateral fire spread using the WRF-Fire coupled atmosphere–fire numerical model

    OpenAIRE

    Simpson, C. C.; Sharples, J. J.; Evans, J. P.

    2014-01-01

    Fire channelling is a form of dynamic fire behaviour, during which a wildland fire spreads rapidly across a steep lee-facing slope in a direction transverse to the background winds, and is often accompanied by a downwind extension of the active flaming region and extreme pyro-convection. Recent work using the WRF-Fire coupled atmosphere-fire model has demonstrated that fire channelling can be characterised as vorticity-driven lateral fire spread (VDLS). In t...

  16. Interdisciplinary knowledge translation: lessons learned from a mental health: fire service collaboration.

    Science.gov (United States)

    Henderson, Joanna L; Mackay, Sherri; Peterson-Badali, Michele

    2010-12-01

    Collaborative approaches are being increasingly advocated for addressing a variety of health, mental health and social needs for children, youth and families. Factors important for effective knowledge translation of collaborative approaches of service delivery across disciplines, however, have not been rigorously examined. TAPP-C: The Arson Prevention Program for Children is an intervention program for child and adolescent firesetters provided collaboratively by fire service and mental health professionals. The present study examined the adopter, innovation, and dissemination characteristics associated with TAPP-C implementation, protocol adherence and extent of collaboration by 241 community-based fire service professionals from communities across Ontario. Results revealed that dissemination factors are particularly important for understanding program implementation, adherence and cross-discipline collaboration. Moreover, the findings of this study show significant benefits to both within discipline (intra-disciplinary) and across discipline (interdisciplinary) knowledge translation strategies.

  17. Wildland Fire Behaviour Case Studies and Fuel Models for Landscape-Scale Fire Modeling

    Directory of Open Access Journals (Sweden)

    Paul-Antoine Santoni

    2011-01-01

    Full Text Available This work presents the extension of a physical model for the spreading of surface fire at landscape scale. In previous work, the model was validated at laboratory scale for fire spreading across litters. The model was then modified to consider the structure of actual vegetation and was included in the wildland fire calculation system Forefire that allows converting the two-dimensional model of fire spread to three dimensions, taking into account spatial information. Two wildland fire behavior case studies were elaborated and used as a basis to test the simulator. Both fires were reconstructed, paying attention to the vegetation mapping, fire history, and meteorological data. The local calibration of the simulator required the development of appropriate fuel models for shrubland vegetation (maquis for use with the model of fire spread. This study showed the capabilities of the simulator during the typical drought season characterizing the Mediterranean climate when most wildfires occur.

  18. The US Fire Learning Network: Springing a Rigidity Trap through Multiscalar Collaborative Networks

    Directory of Open Access Journals (Sweden)

    William Hale. Butler

    2010-09-01

    Full Text Available Wildland fire management in the United States is caught in a rigidity trap, an inability to apply novelty and innovation in the midst of crisis. Despite wide recognition that public agencies should engage in ecological fire restoration, fire suppression still dominates planning and management, and restoration has failed to gain traction. The U.S. Fire Learning Network (FLN, a multiscalar collaborative endeavor established in 2002 by federal land management agencies and The Nature Conservancy, offers the potential to overcome barriers that inhibit restoration planning and management. By circulating people, planning products, and information among landscape- and regional-scale collaboratives, this network has facilitated the development and dissemination of innovative approaches to ecological fire restoration. Through experimentation and innovation generated in the network, the FLN has fostered change by influencing fire and land management plans as well as federal policy. We suggest that multiscalar collaborative planning networks such as the FLN can facilitate overcoming the rigidity traps that prevent resource management agencies from responding to complex cross-scalar problems.

  19. Linking 3D spatial models of fuels and fire: Effects of spatial heterogeneity on fire behavior

    Science.gov (United States)

    Russell A. Parsons; William E. Mell; Peter McCauley

    2011-01-01

    Crownfire endangers fire fighters and can have severe ecological consequences. Prediction of fire behavior in tree crowns is essential to informed decisions in fire management. Current methods used in fire management do not address variability in crown fuels. New mechanistic physics-based fire models address convective heat transfer with computational fluid dynamics (...

  20. Fire Propagation Tracing Model in the Explicit Treatment of Events of Fire PSA

    International Nuclear Information System (INIS)

    Lim, Ho Gon; Han, Sang Hoon; Yang, Jun Eon

    2010-01-01

    The fire propagation model in a fire PSA has not been considered analytically instead a simplified analyst's intuition was used to consider the fire propagation path. A fire propagation equation is developed to trace all the propagation paths in the fire area in which a zone is defined to identify various fire ignition sources. An initiation of fire is assumed to take place in a zone. Then, the propagation is modeled with a Boolean equation. Since the explicit fire PSA modeling requires an exclusive event set to sum up the..., exclusive event sets are derived from the fire propagation equation. As an example, we show the exclusive set for a 2x3 rectangular fire zone. Also, the applicability the developed fire equation is discussed when the number of zone increases including the limitation of the explicit fire PSA modeling method

  1. Innovating through collaborative business models

    DEFF Research Database (Denmark)

    Gjerding, Allan Næs; Kringelum, Louise Tina Brøns

    The present paper presents a novel generalization of business model innovation as an activity taking place across a development and an extension zone, where business model innovation occurs as minor, medium and major changes within both zones. The model explains the process of creating new activi......, and that there exists a dialec-tical relationship between sources of selection and sources of survival, which tend to re-inforce one another. This constitutes a new aspect of business model innovation.......The present paper presents a novel generalization of business model innovation as an activity taking place across a development and an extension zone, where business model innovation occurs as minor, medium and major changes within both zones. The model explains the process of creating new activity......-ered as a coherent system. The generalization is explicated in terms of different domi-nant market logics in which collaborative efforts can be positioned. Underlying this presentation, the paper argues that business model innovation involves uncertainty to the degree that innovation is based on cooperative efforts...

  2. Coupled atmosphere-wildland fire modelling

    Directory of Open Access Journals (Sweden)

    Jacques Henri Balbi

    2009-10-01

    Full Text Available Simulating the interaction between fire and atmosphere is critical to the estimation of the rate of spread of the fire. Wildfire’s convection (i.e., entire plume can modify the local meteorology throughout the atmospheric boundary layer and consequently affect the fire propagation speed and behaviour. In this study, we use for the first time the Méso-NH meso-scale numerical model coupled to the point functional ForeFire simplified physical front-tracking wildfire model to investigate the differences introduced by the atmospheric feedback in propagation speed and behaviour. Both numerical models have been developed as research tools for operational models and are currently used to forecast localized extreme events. These models have been selected because they can be run coupled and support decisions in wildfire management in France and Europe. The main originalities of this combination reside in the fact that Méso-NH is run in a Large Eddy Simulation (LES configuration and that the rate of spread model used in ForeFire provides a physical formulation to take into account the effect of wind and slope. Simulations of typical experimental configurations show that the numerical atmospheric model is able to reproduce plausible convective effects of the heat produced by the fire. Numerical results are comparable to estimated values for fire-induced winds and present behaviour similar to other existing numerical approaches.

  3. Virtual Business Collaboration Conceptual Knowledge Model (VBCKM)

    OpenAIRE

    Morcous Massoud Yassa; Fatama A Omara; Hesham A Hassan

    2012-01-01

    Within the context of virtual business collaboration modeling, many pervious works have been accepted to consider some essential virtual business collaborative models. A practical dynamic virtual organization may be a combination of those models and some other elemental features with some modifications to meet the business opportunity requirements. Therefore, some guidelines and rules are needed to help in constructing a practical collaboration model. This work aims to determine the essential...

  4. Modelling the probability of building fires

    Directory of Open Access Journals (Sweden)

    Vojtěch Barták

    2014-12-01

    Full Text Available Systematic spatial risk analysis plays a crucial role in preventing emergencies.In the Czech Republic, risk mapping is currently based on the risk accumulationprinciple, area vulnerability, and preparedness levels of Integrated Rescue Systemcomponents. Expert estimates are used to determine risk levels for individualhazard types, while statistical modelling based on data from actual incidents andtheir possible causes is not used. Our model study, conducted in cooperation withthe Fire Rescue Service of the Czech Republic as a model within the Liberec andHradec Králové regions, presents an analytical procedure leading to the creation ofbuilding fire probability maps based on recent incidents in the studied areas andon building parameters. In order to estimate the probability of building fires, aprediction model based on logistic regression was used. Probability of fire calculatedby means of model parameters and attributes of specific buildings can subsequentlybe visualized in probability maps.

  5. The Fire Locating and Modeling of Burning Emissions (FLAMBE) Project

    Science.gov (United States)

    Reid, J. S.; Prins, E. M.; Westphal, D.; Richardson, K.; Christopher, S.; Schmidt, C.; Theisen, M.; Eck, T.; Reid, E. A.

    2001-12-01

    The Fire Locating and Modeling of Burning Emissions (FLAMBE) project was initiated by NASA, the US Navy and NOAA to monitor biomass burning and burning emissions on a global scale. The idea behind the mission is to integrate remote sensing data with global and regional transport models in real time for the purpose of providing the scientific community with smoke and fire products for planning and research purposes. FLAMBE is currently utilizing real time satellite data from GOES satellites, fire products based on the Wildfire Automated Biomass Burning Algorithm (WF_ABBA) are generated for the Western Hemisphere every 30 minutes with only a 90 minute processing delay. We are currently collaborating with other investigators to gain global coverage. Once generated, the fire products are used to input smoke fluxes into the NRL Aerosol Analysis and Prediction System, where advection forecasts are performed for up to 6 days. Subsequent radiative transfer calculations are used to estimate top of atmosphere and surface radiative forcing as well as surface layer visibility. Near real time validation is performed using field data collected by Aerosol Robotic Network (AERONET) Sun photometers. In this paper we fully describe the FLAMBE project and data availability. Preliminary result from the previous year will also be presented, with an emphasis on the development of algorithms to determine smoke emission fluxes from individual fire products. Comparisons to AERONET Sun photometer data will be made.

  6. Aids to determining fuel models for estimating fire behavior

    Science.gov (United States)

    Hal E. Anderson

    1982-01-01

    Presents photographs of wildland vegetation appropriate for the 13 fuel models used in mathematical models of fire behavior. Fuel model descriptions include fire behavior associated with each fuel and its physical characteristics. A similarity chart cross-references the 13 fire behavior fuel models to the 20 fuel models used in the National Fire Danger Rating System....

  7. Parametric analysis of fire model CFAST

    International Nuclear Information System (INIS)

    Lee, Y. H.; Yang, J. Y.; Kim, J. H.

    2004-01-01

    This paper describes the pump room fire of the nuclear power plant using CFAST fire modeling code developed by NIST. It is determined by the constrained or unconstrained fire, Lower Oxygen Limit (LOL), Radiative Fraction (RF), and the times to open doors, which are the input parameters of CAFST. According to the results, pump room fire is ventilation-controlled fire, so it is adequate that the value of LOL is 10% which is also the default value. It is appeared that the RF does not change the temperature of the upper gas layer. But the level of opening of the penetrating area and the times to opening it have an effect on the temperature of the upper layer, so it is determined that the results of it should be carefully analyzed

  8. Towards a Model of Collaborative Intention

    DEFF Research Database (Denmark)

    Razmerita, Liana; Kirchner, Kathrin; Hockerts, Kai

    2018-01-01

    outcome expectancy and communal support expectancy. Additionally, we reveal that collaborative outcome expectancy is predicated on individuals’ belief about his/her ability to collaborate whereas communal support expectancy is impacted by the individual’s perception of communal influence.......Disentangling factors that affect one’s intention to collaborate is an important endeavor for management education, especially for globally dispersed groups of students. Drawing on a synthesis of four theories, we advance a model of collaboration intentions that embodies both individual...... and communal level drivers of individuals’ intention to participate in virtual collaboration. The model is validated based on data collected from 2,517 participants in a Massive Online Open Course (MOOC). Results demonstrate that attitudes towards virtual collaboration are predicted by both collaborative...

  9. A MODEL OF ASEAN COLLABORATION IN TOURISM

    OpenAIRE

    Wong, EPY; Mistilis, N; Dwyer, L

    2011-01-01

    Intergovernmental collaboration in tourism among ASEAN nations has received little attention in the literature despite the significant contribution that tourism makes to the region. In this paper, the authors propose a model that displays the mechanism of ASEAN tourism collaboration. The model emphasizes the environments in which collaboration takes place. It also highlights the interactivity of various components: among actors, between the institutional arrangement and the actors, and the fe...

  10. Simulating wall and corner fire tests on wood products with the OSU room fire model

    Science.gov (United States)

    H. C. Tran

    1994-01-01

    This work demonstrates the complexity of modeling wall and corner fires in a compartment. The model chosen for this purpose is the Ohio State University (OSU) room fire model. This model was designed to simulate fire growth on walls in a compartment and therefore lends itself to direct comparison with standard room test results. The model input were bench-scale data...

  11. A Distributional Representation Model For Collaborative Filtering

    OpenAIRE

    Junlin, Zhang; Heng, Cai; Tongwen, Huang; Huiping, Xue

    2015-01-01

    In this paper, we propose a very concise deep learning approach for collaborative filtering that jointly models distributional representation for users and items. The proposed framework obtains better performance when compared against current state-of-art algorithms and that made the distributional representation model a promising direction for further research in the collaborative filtering.

  12. Fire modeling of the Heiss Dampf Reaktor containment

    International Nuclear Information System (INIS)

    Nicolette, V.F.; Yang, K.T.

    1995-09-01

    This report summarizes Sandia National Laboratories' participation in the fire modeling activities for the German Heiss Dampf Reaktor (HDR) containment building, under the sponsorship of the United States Nuclear Regulatory Commission. The purpose of this report is twofold: (1) to summarize Sandia's participation in the HDR fire modeling efforts and (2) to summarize the results of the international fire modeling community involved in modeling the HDR fire tests. Additional comments, on the state of fire modeling and trends in the international fire modeling community are also included. It is noted that, although the trend internationally in fire modeling is toward the development of the more complex fire field models, each type of fire model has something to contribute to the understanding of fires in nuclear power plants

  13. A hydroclimatic model of global fire patterns

    Science.gov (United States)

    Boer, Matthias

    2015-04-01

    Satellite-based earth observation is providing an increasingly accurate picture of global fire patterns. The highest fire activity is observed in seasonally dry (sub-)tropical environments of South America, Africa and Australia, but fires occur with varying frequency, intensity and seasonality in almost all biomes on Earth. The particular combination of these fire characteristics, or fire regime, is known to emerge from the combined influences of climate, vegetation, terrain and land use, but has so far proven difficult to reproduce by global models. Uncertainty about the biophysical drivers and constraints that underlie current global fire patterns is propagated in model predictions of how ecosystems, fire regimes and biogeochemical cycles may respond to projected future climates. Here, I present a hydroclimatic model of global fire patterns that predicts the mean annual burned area fraction (F) of 0.25° x 0.25° grid cells as a function of the climatic water balance. Following Bradstock's four-switch model, long-term fire activity levels were assumed to be controlled by fuel productivity rates and the likelihood that the extant fuel is dry enough to burn. The frequency of ignitions and favourable fire weather were assumed to be non-limiting at long time scales. Fundamentally, fuel productivity and fuel dryness are a function of the local water and energy budgets available for the production and desiccation of plant biomass. The climatic water balance summarizes the simultaneous availability of biologically usable energy and water at a site, and may therefore be expected to explain a significant proportion of global variation in F. To capture the effect of the climatic water balance on fire activity I focused on the upper quantiles of F, i.e. the maximum level of fire activity for a given climatic water balance. Analysing GFED4 data for annual burned area together with gridded climate data, I found that nearly 80% of the global variation in the 0.99 quantile of F

  14. Applications of Living Fire PRA models to Fire Protection Significance Determination Process in Taiwan

    International Nuclear Information System (INIS)

    De-Cheng, Chen; Chung-Kung, Lo; Tsu-Jen, Lin; Ching-Hui, Wu; Lin, James C.

    2004-01-01

    The living fire probabilistic risk assessment (PRA) models for all three operating nuclear power plants (NPPs) in Taiwan had been established in December 2000. In that study, a scenario-based PRA approach was adopted to systematically evaluate the fire and smoke hazards and associated risks. Using these fire PRA models developed, a risk-informed application project had also been completed in December 2002 for the evaluation of cable-tray fire-barrier wrapping exemption. This paper presents a new application of the fire PRA models to fire protection issues using the fire protection significance determination process (FP SDP). The fire protection issues studied may involve the selection of appropriate compensatory measures during the period when an automatic fire detection or suppression system in a safety-related fire zone becomes inoperable. The compensatory measure can either be a 24-hour fire watch or an hourly fire patrol. The living fire PRA models were used to estimate the increase in risk associated with the fire protection issue in terms of changes in core damage frequency (CDF) and large early release frequency (LERF). In compliance with SDP at-power and the acceptance guidelines specified in RG 1.174, the fire protection issues in question can be grouped into four categories; red, yellow, white and green, in accordance with the guidelines developed for FD SDP. A 24-hour fire watch is suggested only required for the yellow condition, while an hourly fire patrol may be adopted for the white condition. More limiting requirement is suggested for the red condition, but no special consideration is needed for the green condition. For the calculation of risk measures, risk impacts from any additional fire scenarios that may have been introduced, as well as more severe initiating events and fire damages that may accompany the fire protection issue should be considered carefully. Examples are presented in this paper to illustrate the evaluation process. (authors)

  15. Business models of the collaborative economy

    DEFF Research Database (Denmark)

    Gyimóthy, Szilvia

    2017-01-01

    Collaborative business models are often equated with disruptive commercial endeavors, epitomised by a handful large global sharing platforms. They represent a certain archetype of business model, extracting profit from market-mediated peer exchanges. A narrow focus on for-profit models obstructs...... coming to terms with the full scope of the collaborative economy phenomena, driven by purposes and actors beyond commercial market domains. This chapter attempts to broaden this perspective by reviewing alternative value creation mechanisms and presents emerging business model archetypes....

  16. Numerical modeling of fires on gas pipelines

    International Nuclear Information System (INIS)

    Zhao Yang; Jianbo Lai; Lu Liu

    2011-01-01

    When natural gas is released through a hole on a high-pressure pipeline, it disperses in the atmosphere as a jet. A jet fire will occur when the leaked gas meets an ignition source. To estimate the dangerous area, the shape and size of the fire must be known. The evolution of the jet fire in air is predicted by using a finite-volume procedure to solve the flow equations. The model is three-dimensional, elliptic and calculated by using a compressibility corrected version of the k - ξ turbulence model, and also includes a probability density function/laminar flamelet model of turbulent non-premixed combustion process. Radiation heat transfer is described using an adaptive version of the discrete transfer method. The model is compared with the experiments about a horizontal jet fire in a wind tunnel in the literature with success. The influence of wind and jet velocity on the fire shape has been investigated. And a correlation based on numerical results for predicting the stoichiometric flame length is proposed. - Research highlights: → We developed a model to predict the evolution of turbulent jet diffusion flames. → Measurements of temperature distributions match well with the numerical predictions. → A correlation has been proposed to predict the stoichiometric flame length. → Buoyancy effects are higher in the numerical results. → The radiative heat loss is bigger in the experimental results.

  17. Multi-compartment Fire Modeling for Switchgear Room using CFAST

    International Nuclear Information System (INIS)

    Han, Kiyoon; Kang, Dae Il; Lim, Ho Gon

    2015-01-01

    In this study, multi-compartment fire modeling for fire propagation scenario from SWGR A to SWGR B is performed using CFAST. New fire PSA method (NUREG/CR-6850) requires that the severity factor is to be calculated by fire modeling. If fire modeling is not performed, the severity factor should be estimated as one conservatively. Also, the possibility of the damages of components and cables located at adjacent compartments should be considered. Detailed fire modeling of multi-compartment fires refers to the evaluation of fire-generated conditions in one compartment that spread to adjacent ones. In general, the severity factor for multi-compartment fire scenario is smaller than that of single compartment scenario. Preliminary quantification of Hanul Unit 3 fire PSA was performed without fire modeling. As a result of quantification, multi-compartment scenario, fire propagation scenario from switchgear room (SWGR) A to SWGR B, is one of significant contributor to the CDF. In this study, fire modeling of multi-compartment was performed by Consolidated Fire Growth and Smoke Transport (CFAST) to identify the possibility of fire propagation. As a result of fire simulation, it is identified that fire propagation has little influences

  18. Multi-compartment Fire Modeling for Switchgear Room using CFAST

    Energy Technology Data Exchange (ETDEWEB)

    Han, Kiyoon; Kang, Dae Il; Lim, Ho Gon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    In this study, multi-compartment fire modeling for fire propagation scenario from SWGR A to SWGR B is performed using CFAST. New fire PSA method (NUREG/CR-6850) requires that the severity factor is to be calculated by fire modeling. If fire modeling is not performed, the severity factor should be estimated as one conservatively. Also, the possibility of the damages of components and cables located at adjacent compartments should be considered. Detailed fire modeling of multi-compartment fires refers to the evaluation of fire-generated conditions in one compartment that spread to adjacent ones. In general, the severity factor for multi-compartment fire scenario is smaller than that of single compartment scenario. Preliminary quantification of Hanul Unit 3 fire PSA was performed without fire modeling. As a result of quantification, multi-compartment scenario, fire propagation scenario from switchgear room (SWGR) A to SWGR B, is one of significant contributor to the CDF. In this study, fire modeling of multi-compartment was performed by Consolidated Fire Growth and Smoke Transport (CFAST) to identify the possibility of fire propagation. As a result of fire simulation, it is identified that fire propagation has little influences.

  19. Review of UCN 5,6 Fire PSA Model based on ANS Fire PRA Standard

    International Nuclear Information System (INIS)

    Yang, Joon Eon; Lee, Yoon Hwan

    2006-12-01

    Recently, under the de-regulation environment, nuclear industry has attempted various approaches to improve the economics of Nuclear Power Plants (NPP). This approach uses the fire risk and performance information to manage the resources effectively and efficiently that are used in the operation of NPP. In fire risk informed/performance-based decision/operation, fire PSA quality is one of the most important things. The nuclear industry and regulatory body of U.S.A have developed a measure to evaluate the quality of fire PSA. ANS (American Nuclear Society) has developed a guidance called 'ANS Fire PRA Methodology Standard'. However, in Korea, there have been no attempts to evaluate the quality of fire PSA model itself. Therefore, we cannot be sure about the quality of fire PSA whether or not the present fire PSA model can be used for the risk-informed applications such as mentioned above. We can say that the evaluation of fire PSA model quality is the basis for the fire risk informed/performance-based decision/operation. In this report, we have evaluated the quality of fire PSA model for Ulchin 5 and 6 units based on the ANS Fire PRA Standard. We, also, have derived what items are to be improved to upgrade the quality of fire PSA model and how it can be improved. This report can be used as the base of the fire risk informed/performance-based decision/operation work in Korea

  20. Relevance Models for Collaborative Filtering

    NARCIS (Netherlands)

    J. Wang (Jun)

    2008-01-01

    htmlabstractCollaborative filtering is the common technique of predicting the interests of a user by collecting preference information from many users. Although it is generally regarded as a key information retrieval technique, its relation to the existing information retrieval theory is unclear.

  1. A Model for Collaborative Runtime Verification

    NARCIS (Netherlands)

    Testerink, Bas; Bulling, Nils; Dastani, Mehdi

    2015-01-01

    Runtime verification concerns checking whether a system execution satisfies a given property. In this paper we propose a model for collaborative runtime verification where a network of local monitors collaborates in order to verify properties of the system. A local monitor has only a local view on

  2. A fire management simulation model using stochastic arrival times

    Science.gov (United States)

    Eric L. Smith

    1987-01-01

    Fire management simulation models are used to predict the impact of changes in the fire management program on fire outcomes. As with all models, the goal is to abstract reality without seriously distorting relationships between variables of interest. One important variable of fire organization performance is the length of time it takes to get suppression units to the...

  3. Data for Room Fire Model Comparisons.

    Science.gov (United States)

    Peacock, Richard D; Davis, Sanford; Babrauskas, Vytenis

    1991-01-01

    With the development of models to predict fire growth and spread in buildings, there has been a concomitant evolution in the measurement and analysis of experimental data in real-scale fires. This report presents the types of analyses that can be used to examine large-scale room fire test data to prepare the data for comparison with zone-based fire models. Five sets of experimental data which can be used to test the limits of a typical two-zone fire model are detailed. A standard set of nomenclature describing the geometry of the building and the quantities measured in each experiment is presented. Availability of ancillary data (such as smaller-scale test results) is included. These descriptions, along with the data (available in computer-readable form) should allow comparisons between the experiment and model predictions. The base of experimental data ranges in complexity from one room tests with individual furniture items to a series of tests conducted in a multiple story hotel equipped with a zoned smoke control system.

  4. Data for Room Fire Model Comparisons

    Science.gov (United States)

    Peacock, Richard D.; Davis, Sanford; Babrauskas, Vytenis

    1991-01-01

    With the development of models to predict fire growth and spread in buildings, there has been a concomitant evolution in the measurement and analysis of experimental data in real-scale fires. This report presents the types of analyses that can be used to examine large-scale room fire test data to prepare the data for comparison with zone-based fire models. Five sets of experimental data which can be used to test the limits of a typical two-zone fire model are detailed. A standard set of nomenclature describing the geometry of the building and the quantities measured in each experiment is presented. Availability of ancillary data (such as smaller-scale test results) is included. These descriptions, along with the data (available in computer-readable form) should allow comparisons between the experiment and model predictions. The base of experimental data ranges in complexity from one room tests with individual furniture items to a series of tests conducted in a multiple story hotel equipped with a zoned smoke control system. PMID:28184121

  5. Human Centered Hardware Modeling and Collaboration

    Science.gov (United States)

    Stambolian Damon; Lawrence, Brad; Stelges, Katrine; Henderson, Gena

    2013-01-01

    In order to collaborate engineering designs among NASA Centers and customers, to in clude hardware and human activities from multiple remote locations, live human-centered modeling and collaboration across several sites has been successfully facilitated by Kennedy Space Center. The focus of this paper includes innovative a pproaches to engineering design analyses and training, along with research being conducted to apply new technologies for tracking, immersing, and evaluating humans as well as rocket, vehic le, component, or faci lity hardware utilizing high resolution cameras, motion tracking, ergonomic analysis, biomedical monitoring, wor k instruction integration, head-mounted displays, and other innovative human-system integration modeling, simulation, and collaboration applications.

  6. Sodium pool fire model for CONACS code

    International Nuclear Information System (INIS)

    Yung, S.C.

    1982-01-01

    The modeling of sodium pool fires constitutes an important ingredient in conducting LMFBR accident analysis. Such modeling capability has recently come under scrutiny at Westinghouse Hanford Company (WHC) within the context of developing CONACS, the Containment Analysis Code System. One of the efforts in the CONACS program is to model various combustion processes anticipated to occur during postulated accident paths. This effort includes the selection or modification of an existing model and development of a new model if it clearly contributes to the program purpose. As part of this effort, a new sodium pool fire model has been developed that is directed at removing some of the deficiencies in the existing models, such as SOFIRE-II and FEUNA

  7. New Approach in Modelling Indonesian Peat Fire Emission

    Science.gov (United States)

    Putra, E. I.; Cochrane, M. A.; Saharjo, B.; Yokelson, R. J.; Stockwell, C.; Vetrita, Y.; Zhang, X.; Hagen, S. C.; Nurhayati, A. D.; Graham, L.

    2017-12-01

    Peat fires are a serious problem for Indonesia, producing devastating environmental effects and making the country the 3rd largest emitter of CO2. Extensive fires ravaged vast areas of peatlands in Sumatra, Kalimantan and Papua during the pronounced El-Nino of 2015, causing international concern when the resultant haze blanketed Indonesia and neighboring countries, severely impacting the health of millions of people. Our recent unprecedented in-situ studies of aerosol and gas emissions from 35 peat fires of varying depths near Palangka Raya, Central Kalimantan have documented the range and variability of emissions from these major fires. We strongly suggest revisions to previously recommended IPPC's emission factors (EFs) from peat fires, notably: CO2 (-8%), CH4 (-55%), NH3 (-86%), and CO (+39%). Our findings clearly showed that Indonesian carbon equivalent measurements (100 years) might have been 19% less than what current IPCC emission factors indicate. The results also demonstrate the toxic air quality in the area with HCN, which is almost only emitted by biomass burning, accounting for 0.28% and the carcinogenic compound formaldehyde 0.04% of emissions. However, considerable variation in emissions may exist between peat fires of different Indonesian peat formations, illustrating the need for additional regional field emissions measurements for parameterizing peatland emissions models for all of Indonesia's major peatland areas. Through the continuous mutual research collaboration between the Indonesian and USA scientists, we will implement our standardized field-based analyses of fuels, hydrology, peat burning characteristics and fire emissions to characterize the three major Indonesian peatland formations across four study provinces (Central Kalimantan, Riau, Jambi and West Papua). We will provide spatial and temporal drivers of the modeled emissions and validate them at a national level using biomass burning emissions estimations derived from Visible

  8. Classifying and comparing spatial models of fire dynamics

    Science.gov (United States)

    Geoffrey J. Cary; Robert E. Keane; Mike D. Flannigan

    2007-01-01

    Wildland fire is a significant disturbance in many ecosystems worldwide and the interaction of fire with climate and vegetation over long time spans has major effects on vegetation dynamics, ecosystem carbon budgets, and patterns of biodiversity. Landscape-Fire-Succession Models (LFSMs) that simulate the linked processes of fire and vegetation development in a spatial...

  9. 76 FR 46330 - NUREG-1934, Nuclear Power Plant Fire Modeling Application Guide (NPP FIRE MAG); Second Draft...

    Science.gov (United States)

    2011-08-02

    ... NUCLEAR REGULATORY COMMISSION [NRC-2009-0568] NUREG-1934, Nuclear Power Plant Fire Modeling... 1023259), ``Nuclear Power Plant Fire Modeling Application Guide (NPP FIRE MAG), Second Draft Report for...), ``Nuclear Power Plant Fire Modeling Application Guide (NPP FIRE MAG), Second Draft for Comment,'' is...

  10. Modeling regional-scale wildland fire emissions with the wildland fire emissions information system

    Science.gov (United States)

    Nancy H.F. French; Donald McKenzie; Tyler Erickson; Benjamin Koziol; Michael Billmire; K. Endsley; Naomi K.Y. Scheinerman; Liza Jenkins; Mary E. Miller; Roger Ottmar; Susan Prichard

    2014-01-01

    As carbon modeling tools become more comprehensive, spatial data are needed to improve quantitative maps of carbon emissions from fire. The Wildland Fire Emissions Information System (WFEIS) provides mapped estimates of carbon emissions from historical forest fires in the United States through a web browser. WFEIS improves access to data and provides a consistent...

  11. Strategic collaboration on business model innovation

    DEFF Research Database (Denmark)

    Gjerding, Allan Næs; Kringelum, Louise Tina Brøns

    The present paper focuses on collaboration as a source of hybridization of the market in the case of business model innovation. The basic argument is that while hybridization economizes on transaction costs, it also gives rise to transaction costs. In effect, transaction costs appears...... as a dialectical phenomenon. The argument is illustrated by a narrative of a case of radical business model innovation. The narrative shows how collaborators economize on transaction costs by developing a mutual understanding and shared interpretation of business model innovation, but at the same time gives rise...

  12. Modelling the meteorological forest fire niche in heterogeneous pyrologic conditions.

    Science.gov (United States)

    De Angelis, Antonella; Ricotta, Carlo; Conedera, Marco; Pezzatti, Gianni Boris

    2015-01-01

    Fire regimes are strongly related to weather conditions that directly and indirectly influence fire ignition and propagation. Identifying the most important meteorological fire drivers is thus fundamental for daily fire risk forecasting. In this context, several fire weather indices have been developed focussing mainly on fire-related local weather conditions and fuel characteristics. The specificity of the conditions for which fire danger indices are developed makes its direct transfer and applicability problematic in different areas or with other fuel types. In this paper we used the low-to-intermediate fire-prone region of Canton Ticino as a case study to develop a new daily fire danger index by implementing a niche modelling approach (Maxent). In order to identify the most suitable weather conditions for fires, different combinations of input variables were tested (meteorological variables, existing fire danger indices or a combination of both). Our findings demonstrate that such combinations of input variables increase the predictive power of the resulting index and surprisingly even using meteorological variables only allows similar or better performances than using the complex Canadian Fire Weather Index (FWI). Furthermore, the niche modelling approach based on Maxent resulted in slightly improved model performance and in a reduced number of selected variables with respect to the classical logistic approach. Factors influencing final model robustness were the number of fire events considered and the specificity of the meteorological conditions leading to fire ignition.

  13. Collaborative Governance Models for Managing Aquatic Resources ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Collaborative Governance Models for Managing Aquatic Resources and Fisheries in the Peruvian ... The idea is to consolidate this knowledge in a model for the participatory ... Linking research to urban planning at the ICLEI World Congress 2018 ... In partnership with UNESCO's Organization for Women in Science for the ...

  14. Collaborative testing of turbulence models

    Science.gov (United States)

    Bradshaw, P.

    1992-12-01

    This project, funded by AFOSR, ARO, NASA, and ONR, was run by the writer with Profs. Brian E. Launder, University of Manchester, England, and John L. Lumley, Cornell University. Statistical data on turbulent flows, from lab. experiments and simulations, were circulated to modelers throughout the world. This is the first large-scale project of its kind to use simulation data. The modelers returned their predictions to Stanford, for distribution to all modelers and to additional participants ('experimenters')--over 100 in all. The object was to obtain a consensus on the capabilities of present-day turbulence models and identify which types most deserve future support. This was not completely achieved, mainly because not enough modelers could produce results for enough test cases within the duration of the project. However, a clear picture of the capabilities of various modeling groups has appeared, and the interaction has been helpful to the modelers. The results support the view that Reynolds-stress transport models are the most accurate.

  15. Perspectives on Fire Research Collaboration in Siberia: What Have We Learned; Why Does It Matter; and Where Do We Go from Here?

    Science.gov (United States)

    Conard, S. G.

    2010-12-01

    My first experience of the vast taiga forests of Russia, and my first chance to meet and work with Russian fire researchers, was at a 1993 conference and field experiment planned jointly by Johann G. Goldammer from Germany and Valentin V. Furyaev from Russia. This meeting was the beginning of a long and fruitful collaboration among US, Canadian, and Russian fire scientists. We all became increasingly aware of the global signifiance of the circumpolar boreal zone, and of the need for better information on the extent and effects of boreal fires. Wildfires are the dominant disturbance regime in the Russian boreal zone, burning 10 to 20 million hectares per year. These fires are a significant source of CO2 and other greenhouse gases and aerosols. Our research team published some of the first remote-sensing based estimates of the extent of fire in Russia and of the potential variability in emissions that could result from different burning conditions. Through a series of 20 prescribed burns we were able to mimic a wide range of burning conditions and obtain information on the impacts on soils, vegetation, and fuel consumption. Based on these experimental fires, we have modeled the effects of weather and fuels on fuel consumption and other factors, and related fire characteristics to emissions, carbon stocks, and soil and vegetation processes. For the past 10 years, we have focused on the ecosystem effects of fires of varying severity in the Scots pine and mixed larch forests of central Siberia, on improved remote-sensing based estimates of burned area and fire effects, and on relating fire weather indices to fire potential and fuel consumption. Logging is an increasingly important disturbance in Russia’s forests, and logged sites, with their high fuel loads seem particularly susceptible to fire. We are currently studying interactions between logging and fire, with an emphasis on the differences in fuel consumption, emissions, and carbon stocks when fires burn in

  16. The status and challenge of global fire modelling

    Science.gov (United States)

    Hantson, Stijn; Arneth, Almut; Harrison, Sandy P.; Kelley, Douglas I.; Prentice, I. Colin; Rabin, Sam S.; Archibald, Sally; Mouillot, Florent; Arnold, Steve R.; Artaxo, Paulo; Bachelet, Dominique; Ciais, Philippe; Forrest, Matthew; Friedlingstein, Pierre; Hickler, Thomas; Kaplan, Jed O.; Kloster, Silvia; Knorr, Wolfgang; Lasslop, Gitta; Li, Fang; Mangeon, Stephane; Melton, Joe R.; Meyn, Andrea; Sitch, Stephen; Spessa, Allan; van der Werf, Guido R.; Voulgarakis, Apostolos; Yue, Chao

    2016-06-01

    Biomass burning impacts vegetation dynamics, biogeochemical cycling, atmospheric chemistry, and climate, with sometimes deleterious socio-economic impacts. Under future climate projections it is often expected that the risk of wildfires will increase. Our ability to predict the magnitude and geographic pattern of future fire impacts rests on our ability to model fire regimes, using either well-founded empirical relationships or process-based models with good predictive skill. While a large variety of models exist today, it is still unclear which type of model or degree of complexity is required to model fire adequately at regional to global scales. This is the central question underpinning the creation of the Fire Model Intercomparison Project (FireMIP), an international initiative to compare and evaluate existing global fire models against benchmark data sets for present-day and historical conditions. In this paper we review how fires have been represented in fire-enabled dynamic global vegetation models (DGVMs) and give an overview of the current state of the art in fire-regime modelling. We indicate which challenges still remain in global fire modelling and stress the need for a comprehensive model evaluation and outline what lessons may be learned from FireMIP.

  17. University - industry collaborations: models, drivers and cultures.

    Science.gov (United States)

    Ehrismann, Dominic; Patel, Dhavalkumar

    2015-01-01

    The way academic institutions and pharmaceutical companies have been approaching collaborations has changed significantly in recent years. A multitude of interaction models were tested and critical factors that drive successful collaborations have been proposed. Based on this experience the current consensus in the pharmaceutical industry is to pursue one of two strategies: an open innovation approach to source discoveries wherever they occur, or investing selectively into scientific partnerships that churn out inventions that can be translated from bench to bedside internally. While these strategies may be intuitive, to form and build sustainable relationships between academia and large multinational healthcare enterprises is proving challenging. In this article we explore some of the more testing aspects of these collaborations, approaches that various industrial players have taken and provide our own views on the matter. We found that understanding and respecting each other's organisational culture and combining the intellectual and technological assets to answer big scientific questions accelerates and improves the quality of every collaboration. Upon discussing the prevailing cooperation models in the university - industry domain, we assert that science-driven collaborations where risks and rewards are shared equally without a commercial agenda in mind are the most impactful.

  18. Modelling Variable Fire Severity in Boreal Forests: Effects of Fire Intensity and Stand Structure.

    Science.gov (United States)

    Miquelajauregui, Yosune; Cumming, Steven G; Gauthier, Sylvie

    2016-01-01

    It is becoming clear that fires in boreal forests are not uniformly stand-replacing. On the contrary, marked variation in fire severity, measured as tree mortality, has been found both within and among individual fires. It is important to understand the conditions under which this variation can arise. We integrated forest sample plot data, tree allometries and historical forest fire records within a diameter class-structured model of 1.0 ha patches of mono-specific black spruce and jack pine stands in northern Québec, Canada. The model accounts for crown fire initiation and vertical spread into the canopy. It uses empirical relations between fire intensity, scorch height, the percent of crown scorched and tree mortality to simulate fire severity, specifically the percent reduction in patch basal area due to fire-caused mortality. A random forest and a regression tree analysis of a large random sample of simulated fires were used to test for an effect of fireline intensity, stand structure, species composition and pyrogeographic regions on resultant severity. Severity increased with intensity and was lower for jack pine stands. The proportion of simulated fires that burned at high severity (e.g. >75% reduction in patch basal area) was 0.80 for black spruce and 0.11 for jack pine. We identified thresholds in intensity below which there was a marked sensitivity of simulated fire severity to stand structure, and to interactions between intensity and structure. We found no evidence for a residual effect of pyrogeographic region on simulated severity, after the effects of stand structure and species composition were accounted for. The model presented here was able to produce variation in fire severity under a range of fire intensity conditions. This suggests that variation in stand structure is one of the factors causing the observed variation in boreal fire severity.

  19. The General Education Collaboration Model: A Model for Successful Mainstreaming.

    Science.gov (United States)

    Simpson, Richard L.; Myles, Brenda Smith

    1990-01-01

    The General Education Collaboration Model is designed to support general educators teaching mainstreamed disabled students, through collaboration with special educators. The model is based on flexible departmentalization, program ownership, identification and development of supportive attitudes, student assessment as a measure of program…

  20. Improved Collaborative Filtering Algorithm using Topic Model

    Directory of Open Access Journals (Sweden)

    Liu Na

    2016-01-01

    Full Text Available Collaborative filtering algorithms make use of interactions rates between users and items for generating recommendations. Similarity among users or items is calculated based on rating mostly, without considering explicit properties of users or items involved. In this paper, we proposed collaborative filtering algorithm using topic model. We describe user-item matrix as document-word matrix and user are represented as random mixtures over item, each item is characterized by a distribution over users. The experiments showed that the proposed algorithm achieved better performance compared the other state-of-the-art algorithms on Movie Lens data sets.

  1. Modelling of fire spread in car parks

    NARCIS (Netherlands)

    Noordijk, L.M.; Lemaire, A.D.

    2005-01-01

    Currently, design codes assume that in a car park fire at most 3-4 vehicles are on fire at the same time. Recent incidents in car parks have drawn international attention to such assumptions and have raised questions as to the fire spreading mechanism and the resulting fire load on the structure.

  2. Fire simulation of pool fire with effects of a ventilation controlled compartment by using a fire model, CFAST

    International Nuclear Information System (INIS)

    Hattori, Yasuo; Suto, Hitoshi; Shirai, Koji; Eguchi, Yuzuru; Matsuyama, Ken

    2015-01-01

    The basic performance for numerical analysis of fire parameters in a compartment by using a zone model, CFAST (Consolidated model of Fire growth And Smoke Transport), which has been widely applied for fire protection design of buildings, was examined. Special attentions were paid to the effects of compartment geometry under poor ventilation conditions with mechanical systems. The simulations were carried out under conditions corresponding to previous experiments, in which fire parameters have been precisely measured. The comparison between numerical simulations and experiments indicated that the CFAST principally has a capability to represent the time-histories of air-temperature in the high air-temperature layer generated in the vicinity of ceiling of the compartment, by applying the proper boundary conditions. These results suggest that numerical analysis for time-series of air temperature and smoke concentration in compartments must be a powerful tool for discussion on validity of fire protection schemes. (author)

  3. Sensitivity Analysis of a Simplified Fire Dynamic Model

    DEFF Research Database (Denmark)

    Sørensen, Lars Schiøtt; Nielsen, Anker

    2015-01-01

    This paper discusses a method for performing a sensitivity analysis of parameters used in a simplified fire model for temperature estimates in the upper smoke layer during a fire. The results from the sensitivity analysis can be used when individual parameters affecting fire safety are assessed...

  4. One thousand years of fires: Integrating proxy and model data

    Directory of Open Access Journals (Sweden)

    Natalie Marie Kehrwald

    2016-04-01

    Full Text Available The current fires raging across Indonesia are emitting more carbon than the annual fossil fuel emissions of Germany or Japan, and the fires are still consuming vast tracts of rainforest and peatlands. The National Interagency Fire Center (www.nifc.gov notes that 2015 is one worst fire years on record in the U.S., where more than 9 million acres burned -- equivalent to the combined size of Massachusetts and New Jersey. The U.S. and Indonesian fires have already displaced tens of thousands of people, and their impacts on ecosystems are still unclear. In the case of Indonesia, the burning peat is destroying much of the existing soil, with unknown implications for the type of vegetation regrowth. Such large fires result from a combination of fire management practices, increasing anthropogenic land use, and a changing climate. The expected increase in fire activity in the upcoming decades has led to a surge in research trying to understand their causes, the factors that may have influenced similar times of fire activity in the past, and the implications of such fire activity in the future. Multiple types of complementary data provide information on the impacts of current fires and the extent of past fires. The wide array of data encompasses different spatial and temporal resolutions (Figure 1 and includes fire proxy information such as charcoal and tree ring fire scars, observational records, satellite products, modern emissions data, fire models within global land cover and vegetation models, and sociodemographic data for modeling past human land use and ignition frequency. Any single data type is more powerful when combined with another source of information. Merging model and proxy data enables analyses of how fire activity modifies vegetation distribution, air and water quality, and proximity to cities; these analyses in turn support land management decisions relating to conservation and development.

  5. Experimental Benchmarking of Fire Modeling Simulations. Final Report

    International Nuclear Information System (INIS)

    Greiner, Miles; Lopez, Carlos

    2003-01-01

    A series of large-scale fire tests were performed at Sandia National Laboratories to simulate a nuclear waste transport package under severe accident conditions. The test data were used to benchmark and adjust the Container Analysis Fire Environment (CAFE) computer code. CAFE is a computational fluid dynamics fire model that accurately calculates the heat transfer from a large fire to a massive engulfed transport package. CAFE will be used in transport package design studies and risk analyses

  6. Evaluation of fire models for nuclear power plant applications. Benchmark exercise no. 4: Fuel pool fire inside a compartment - International panel report

    International Nuclear Information System (INIS)

    Klein-Hessling, W.; Roewekamp, M.; Riese, O.

    2006-11-01

    Fire simulations as well as their analytical validation procedures have gained more and more significance, particularly in the context of the fire safety analysis for operating nuclear power plants. Meanwhile, fire simulation models have been adapted as analytical tools for a risk oriented fire safety assessment. Calculated predictions can be used, on the one hand, for the improvements and upgrades of fire protection in nuclear power plants by the licensees and, on the other hand, as a tool for reproducible and clearly understandable estimations in assessing the available and/or foreseen fire protection measures by the authorities and their experts. For consideration of such aspects in the context of implementing new nuclear fire protection standards or of updating existing ones, an 'International Collaborative Project to Evaluate Fire Models for Nuclear Power Plant Applications' also known as the 'International Collaborative Fire Model Project' (ICFMP) was started in 1999. It has made use of the experience and knowledge of a variety of worldwide expert institutions in this field to assess and improve, if necessary, the state-of-the-art with respect to modeling fires in nuclear power plants and other nuclear installations. This document contains the results of the ICFMP Benchmark Exercise No. 4, where two fuel pool fire experiments in an enclosure with two different natural vent sizes have been considered. Analyzing the results of different fire simulation codes and code types provides some indications with respect to the uncertainty of the results. This information is especially important in setting uncertainty parameters in probabilistic risk studies and to provide general insights concerning the applicability and limitations in the application of different types of fire simulation codes for this type of fire scenario and boundary conditions. During the benchmark procedure the participants performed different types of calculations. These included totally blind

  7. Modeling fire occurrence as a function of landscape

    Science.gov (United States)

    Loboda, T. V.; Carroll, M.; DiMiceli, C.

    2011-12-01

    Wildland fire is a prominent component of ecosystem functioning worldwide. Nearly all ecosystems experience the impact of naturally occurring or anthropogenically driven fire. Here, we present a spatially explicit and regionally parameterized Fire Occurrence Model (FOM) aimed at developing fire occurrence estimates at landscape and regional scales. The model provides spatially explicit scenarios of fire occurrence based on the available records from fire management agencies, satellite observations, and auxiliary geospatial data sets. Fire occurrence is modeled as a function of the risk of ignition, potential fire behavior, and fire weather using internal regression tree-driven algorithms and empirically established, regionally derived relationships between fire occurrence, fire behavior, and fire weather. The FOM presents a flexible modeling structure with a set of internal globally available default geospatial independent and dependent variables. However, the flexible modeling environment adapts to ingest a variable number, resolution, and content of inputs provided by the user to supplement or replace the default parameters to improve the model's predictive capability. A Southern California FOM instance (SC FOM) was developed using satellite assessments of fire activity from a suite of Landsat and Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data, Monitoring Trends in Burn Severity fire perimeters, and auxiliary geospatial information including land use and ownership, utilities, transportation routes, and the Remote Automated Weather Station data records. The model was parameterized based on satellite data acquired between 2001 and 2009 and fire management fire perimeters available prior to 2009. SC FOM predictive capabilities were assessed using observed fire occurrence available from the MODIS active fire product during 2010. The results show that SC FOM provides a realistic estimate of fire occurrence at the landscape level: the fraction of

  8. Large urban fire environment: trends and model city predictions

    International Nuclear Information System (INIS)

    Larson, D.A.; Small, R.D.

    1983-01-01

    The urban fire environment that would result from a megaton-yield nuclear weapon burst is considered. The dependence of temperatures and velocities on fire size, burning intensity, turbulence, and radiation is explored, and specific calculations for three model urban areas are presented. In all cases, high velocity fire winds are predicted. The model-city results show the influence of building density and urban sprawl on the fire environment. Additional calculations consider large-area fires with the burning intensity reduced in a blast-damaged urban center

  9. Development and validation of a physics-based urban fire spread model

    OpenAIRE

    HIMOTO, Keisuke; TANAKA, Takeyoshi

    2008-01-01

    A computational model for fire spread in a densely built urban area is developed. The model is distinct from existing models in that it explicitly describes fire spread phenomena with physics-based knowledge achieved in the field of fire safety engineering. In the model, urban fire is interpreted as an ensemble of multiple building fires; that is, the fire spread is simulated by predicting behaviors of individual building fires under the thermal influence of neighboring building fires. Adopte...

  10. Comparing effects of fire modeling methods on simulated fire patterns and succession: a case study in the Missouri Ozarks

    Science.gov (United States)

    Jian Yang; Hong S. He; Brian R. Sturtevant; Brian R. Miranda; Eric J. Gustafson

    2008-01-01

    We compared four fire spread simulation methods (completely random, dynamic percolation. size-based minimum travel time algorithm. and duration-based minimum travel time algorithm) and two fire occurrence simulation methods (Poisson fire frequency model and hierarchical fire frequency model) using a two-way factorial design. We examined these treatment effects on...

  11. Mapping and modeling of physician collaboration network.

    Science.gov (United States)

    Uddin, Shahadat; Hamra, Jafar; Hossain, Liaquat

    2013-09-10

    Effective provisioning of healthcare services during patient hospitalization requires collaboration involving a set of interdependent complex tasks, which needs to be carried out in a synergistic manner. Improved patients' outcome during and after hospitalization has been attributed to how effective different health services provisioning groups carry out their tasks in a coordinated manner. Previous studies have documented the underlying relationships between collaboration among physicians on the effective outcome in delivering health services for improved patient outcomes. However, there are very few systematic empirical studies with a focus on the effect of collaboration networks among healthcare professionals and patients' medical condition. On the basis of the fact that collaboration evolves among physicians when they visit a common hospitalized patient, in this study, we first propose an approach to map collaboration network among physicians from their visiting information to patients. We termed this network as physician collaboration network (PCN). Then, we use exponential random graph (ERG) models to explore the microlevel network structures of PCNs and their impact on hospitalization cost and hospital readmission rate. ERG models are probabilistic models that are presented by locally determined explanatory variables and can effectively identify structural properties of networks such as PCN. It simplifies a complex structure down to a combination of basic parameters such as 2-star, 3-star, and triangle. By applying our proposed mapping approach and ERG modeling technique to the electronic health insurance claims dataset of a very large Australian health insurance organization, we construct and model PCNs. We notice that the 2-star (subset of 3 nodes in which 1 node is connected to each of the other 2 nodes) parameter of ERG has significant impact on hospitalization cost. Further, we identify that triangle (subset of 3 nodes in which each node is connected to

  12. Modeling issues in nuclear plant fire risk analysis

    International Nuclear Information System (INIS)

    Siu, N.

    1989-01-01

    This paper discusses various issues associated with current models for analyzing the risk due to fires in nuclear power plants. Particular emphasis is placed on the fire growth and suppression models, these being unique to the fire portion of the overall risk analysis. Potentially significant modeling improvements are identified; also discussed are a variety of modeling issues where improvements will help the credibility of the analysis, without necessarily changing the computed risk significantly. The mechanistic modeling of fire initiation is identified as a particularly promising improvement for reducing the uncertainties in the predicted risk. 17 refs., 5 figs. 2 tabs

  13. Collaborative deliberation: a model for patient care.

    Science.gov (United States)

    Elwyn, Glyn; Lloyd, Amy; May, Carl; van der Weijden, Trudy; Stiggelbout, Anne; Edwards, Adrian; Frosch, Dominick L; Rapley, Tim; Barr, Paul; Walsh, Thom; Grande, Stuart W; Montori, Victor; Epstein, Ronald

    2014-11-01

    Existing theoretical work in decision making and behavior change has focused on how individuals arrive at decisions or form intentions. Less attention has been given to theorizing the requirements that might be necessary for individuals to work collaboratively to address difficult decisions, consider new alternatives, or change behaviors. The goal of this work was to develop, as a forerunner to a middle range theory, a conceptual model that considers the process of supporting patients to consider alternative health care options, in collaboration with clinicians, and others. Theory building among researchers with experience and expertise in clinician-patient communication, using an iterative cycle of discussions. We developed a model composed of five inter-related propositions that serve as a foundation for clinical communication processes that honor the ethical principles of respecting individual agency, autonomy, and an empathic approach to practice. We named the model 'collaborative deliberation.' The propositions describe: (1) constructive interpersonal engagement, (2) recognition of alternative actions, (3) comparative learning, (4) preference construction and elicitation, and (5) preference integration. We believe the model underpins multiple suggested approaches to clinical practice that take the form of patient centered care, motivational interviewing, goal setting, action planning, and shared decision making. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. Collaboro: a collaborative (meta modeling tool

    Directory of Open Access Journals (Sweden)

    Javier Luis Cánovas Izquierdo

    2016-10-01

    Full Text Available Software development is becoming more and more collaborative, emphasizing the role of end-users in the development process to make sure the final product will satisfy customer needs. This is especially relevant when developing Domain-Specific Modeling Languages (DSMLs, which are modeling languages specifically designed to carry out the tasks of a particular domain. While end-users are actually the experts of the domain for which a DSML is developed, their participation in the DSML specification process is still rather limited nowadays. In this paper, we propose a more community-aware language development process by enabling the active participation of all community members (both developers and end-users from the very beginning. Our proposal, called Collaboro, is based on a DSML itself enabling the representation of change proposals during the language design and the discussion (and trace back of possible solutions, comments and decisions arisen during the collaboration. Collaboro also incorporates a metric-based recommender system to help community members to define high-quality notations for the DSMLs. We also show how Collaboro can be used at the model-level to facilitate the collaborative specification of software models. Tool support is available both as an Eclipse plug-in a web-based solution.

  15. Visions of Restoration in Fire-Adapted Forest Landscapes: Lessons from the Collaborative Forest Landscape Restoration Program

    Science.gov (United States)

    Urgenson, Lauren S.; Ryan, Clare M.; Halpern, Charles B.; Bakker, Jonathan D.; Belote, R. Travis; Franklin, Jerry F.; Haugo, Ryan D.; Nelson, Cara R.; Waltz, Amy E. M.

    2017-02-01

    Collaborative approaches to natural resource management are becoming increasingly common on public lands. Negotiating a shared vision for desired conditions is a fundamental task of collaboration and serves as a foundation for developing management objectives and monitoring strategies. We explore the complex socio-ecological processes involved in developing a shared vision for collaborative restoration of fire-adapted forest landscapes. To understand participant perspectives and experiences, we analyzed interviews with 86 respondents from six collaboratives in the western U.S., part of the Collaborative Forest Landscape Restoration Program established to encourage collaborative, science-based restoration on U.S. Forest Service lands. Although forest landscapes and group characteristics vary considerably, collaboratives faced common challenges to developing a shared vision for desired conditions. Three broad categories of challenges emerged: meeting multiple objectives, collaborative capacity and trust, and integrating ecological science and social values in decision-making. Collaborative groups also used common strategies to address these challenges, including some that addressed multiple challenges. These included use of issue-based recommendations, field visits, and landscape-level analysis; obtaining support from local agency leadership, engaging facilitators, and working in smaller groups (sub-groups); and science engagement. Increased understanding of the challenges to, and strategies for, developing a shared vision of desired conditions is critical if other collaboratives are to learn from these efforts.

  16. Visions of Restoration in Fire-Adapted Forest Landscapes: Lessons from the Collaborative Forest Landscape Restoration Program.

    Science.gov (United States)

    Urgenson, Lauren S; Ryan, Clare M; Halpern, Charles B; Bakker, Jonathan D; Belote, R Travis; Franklin, Jerry F; Haugo, Ryan D; Nelson, Cara R; Waltz, Amy E M

    2017-02-01

    Collaborative approaches to natural resource management are becoming increasingly common on public lands. Negotiating a shared vision for desired conditions is a fundamental task of collaboration and serves as a foundation for developing management objectives and monitoring strategies. We explore the complex socio-ecological processes involved in developing a shared vision for collaborative restoration of fire-adapted forest landscapes. To understand participant perspectives and experiences, we analyzed interviews with 86 respondents from six collaboratives in the western U.S., part of the Collaborative Forest Landscape Restoration Program established to encourage collaborative, science-based restoration on U.S. Forest Service lands. Although forest landscapes and group characteristics vary considerably, collaboratives faced common challenges to developing a shared vision for desired conditions. Three broad categories of challenges emerged: meeting multiple objectives, collaborative capacity and trust, and integrating ecological science and social values in decision-making. Collaborative groups also used common strategies to address these challenges, including some that addressed multiple challenges. These included use of issue-based recommendations, field visits, and landscape-level analysis; obtaining support from local agency leadership, engaging facilitators, and working in smaller groups (sub-groups); and science engagement. Increased understanding of the challenges to, and strategies for, developing a shared vision of desired conditions is critical if other collaboratives are to learn from these efforts.

  17. Evaluation of a post-fire tree mortality model for western US conifers

    Science.gov (United States)

    Sharon M. Hood; Charles W McHugh; Kevin C. Ryan; Elizabeth Reinhardt; Sheri L. Smith

    2007-01-01

    Accurately predicting fire-caused mortality is essential to developing prescribed fire burn plans and post-fire salvage marking guidelines. The mortality model included in the commonly used USA fire behaviour and effects models, the First Order Fire Effects Model (FOFEM), BehavePlus, and the Fire and Fuels Extension to the Forest Vegetation Simulator (FFE-FVS), has not...

  18. FIRE BEHAVIOR PREDICTING MODELS EFFICIENCY IN BRAZILIAN COMMERCIAL EUCALYPT PLANTATIONS

    Directory of Open Access Journals (Sweden)

    Benjamin Leonardo Alves White

    2016-12-01

    Full Text Available Knowing how a wildfire will behave is extremely important in order to assist in fire suppression and prevention operations. Since the 1940’s mathematical models to estimate how the fire will behave have been developed worldwide, however, none of them, until now, had their efficiency tested in Brazilian commercial eucalypt plantations nor in other vegetation types in the country. This study aims to verify the accuracy of the Rothermel (1972 fire spread model, the Byram (1959 flame length model, and the fire spread and length equations derived from the McArthur (1962 control burn meters. To meet these objectives, 105 experimental laboratory fires were done and their results compared with the predicted values from the models tested. The Rothermel and Byram models predicted better than McArthur’s, nevertheless, all of them underestimated the fire behavior aspects evaluated and were statistically different from the experimental data.

  19. Integrating fire behavior models and geospatial analysis for wildland fire risk assessment and fuel management planning

    Science.gov (United States)

    Alan A. Ager; Nicole M. Vaillant; Mark A. Finney

    2011-01-01

    Wildland fire risk assessment and fuel management planning on federal lands in the US are complex problems that require state-of-the-art fire behavior modeling and intensive geospatial analyses. Fuel management is a particularly complicated process where the benefits and potential impacts of fuel treatments must be demonstrated in the context of land management goals...

  20. Forest fire forecasting tool for air quality modelling systems

    International Nuclear Information System (INIS)

    San Jose, R.; Perez, J. L.; Perez, L.; Gonzalez, R. M.; Pecci, J.; Palacios, M.

    2015-01-01

    Adverse effects of smoke on air quality are of great concern; however, even today the estimates of atmospheric fire emissions are a key issue. It is necessary to implement systems for predicting smoke into an air quality modelling system, and in this work a first attempt towards creating a system of this type is presented. Wild land fire spread and behavior are complex phenomena due to both the number of involved physic-chemical factors, and the nonlinear relationship between variables. WRF-Fire was employed to simulate spread and behavior of some real fires occurred in South-East of Spain and North of Portugal. The use of fire behavior models requires the availability of high resolution environmental and fuel data. A new custom fuel moisture content model has been developed. The new module allows each time step to calculate the fuel moisture content of the dead fuels and live fuels. The results confirm that the use of accurate meteorological data and a custom fuel moisture content model is crucial to obtain precise simulations of fire behavior. To simulate air pollution over Europe, we use the regional meteorological-chemistry transport model WRF-Chem. In this contribution, we show the impact of using two different fire emissions inventories (FINN and IS4FIRES) and how the coupled WRF-Fire- Chem model improves the results of the forest fire emissions and smoke concentrations. The impact of the forest fire emissions on concentrations is evident, and it is quite clear from these simulations that the choice of emission inventory is very important. We conclude that using the WRF-fire behavior model produces better results than using forest fire emission inventories although the requested computational power is much higher. (Author)

  1. Forest fire forecasting tool for air quality modelling systems

    Energy Technology Data Exchange (ETDEWEB)

    San Jose, R.; Perez, J.L.; Perez, L.; Gonzalez, R.M.; Pecci, J.; Palacios, M.

    2015-07-01

    Adverse effects of smoke on air quality are of great concern; however, even today the estimates of atmospheric fire emissions are a key issue. It is necessary to implement systems for predicting smoke into an air quality modelling system, and in this work a first attempt towards creating a system of this type is presented. Wildland fire spread and behavior are complex Phenomena due to both the number of involved physic-chemical factors, and the nonlinear relationship between variables. WRF-Fire was employed to simulate spread and behavior of some real fires occurred in South-East of Spain and North of Portugal. The use of fire behavior models requires the availability of high resolution environmental and fuel data. A new custom fuel moisture content model has been developed. The new module allows each time step to calculate the fuel moisture content of the dead fuels and live fuels. The results confirm that the use of accurate meteorological data and a custom fuel moisture content model is crucial to obtain precise simulations of fire behavior. To simulate air pollution over Europe, we use the regional meteorological-chemistry transport model WRF-Chem. In this contribution, we show the impact of using two different fire emissions inventories (FINN and IS4FIRES) and how the coupled WRF-FireChem model improves the results of the forest fire emissions and smoke concentrations. The impact of the forest fire emissions on concentrations is evident, and it is quite clear from these simulations that the choice of emission inventory is very important. We conclude that using the WRF-fire behavior model produces better results than using forest fire emission inventories although the requested computational power is much higher. (Author)

  2. Forest fire forecasting tool for air quality modelling systems

    Energy Technology Data Exchange (ETDEWEB)

    San Jose, R.; Perez, J. L.; Perez, L.; Gonzalez, R. M.; Pecci, J.; Palacios, M.

    2015-07-01

    Adverse effects of smoke on air quality are of great concern; however, even today the estimates of atmospheric fire emissions are a key issue. It is necessary to implement systems for predicting smoke into an air quality modelling system, and in this work a first attempt towards creating a system of this type is presented. Wild land fire spread and behavior are complex phenomena due to both the number of involved physic-chemical factors, and the nonlinear relationship between variables. WRF-Fire was employed to simulate spread and behavior of some real fires occurred in South-East of Spain and North of Portugal. The use of fire behavior models requires the availability of high resolution environmental and fuel data. A new custom fuel moisture content model has been developed. The new module allows each time step to calculate the fuel moisture content of the dead fuels and live fuels. The results confirm that the use of accurate meteorological data and a custom fuel moisture content model is crucial to obtain precise simulations of fire behavior. To simulate air pollution over Europe, we use the regional meteorological-chemistry transport model WRF-Chem. In this contribution, we show the impact of using two different fire emissions inventories (FINN and IS4FIRES) and how the coupled WRF-Fire- Chem model improves the results of the forest fire emissions and smoke concentrations. The impact of the forest fire emissions on concentrations is evident, and it is quite clear from these simulations that the choice of emission inventory is very important. We conclude that using the WRF-fire behavior model produces better results than using forest fire emission inventories although the requested computational power is much higher. (Author)

  3. Concepts for Future Large Fire Modeling

    Science.gov (United States)

    A. P. Dimitrakopoulos; R. E. Martin

    1987-01-01

    A small number of fires escape initial attack suppression efforts and become large, but their effects are significant and disproportionate. In 1983, of 200,000 wildland fires in the United States, only 4,000 exceeded 100 acres. However, these escaped fires accounted for roughly 95 percent of wildfire-related costs and damages (Pyne, 1984). Thus, future research efforts...

  4. FireStem2D — A two-dimensional heat transfer model for simulating tree stem injury in fires

    Science.gov (United States)

    Efthalia K. Chatziefstratiou; Gil Bohrer; Anthony S. Bova; Ravishankar Subramanian; Renato P.M. Frasson; Amy Scherzer; Bret W. Butler; Matthew B. Dickinson

    2013-01-01

    FireStem2D, a software tool for predicting tree stem heating and injury in forest fires, is a physically-based, two-dimensional model of stem thermodynamics that results from heating at the bark surface. It builds on an earlier one-dimensional model (FireStem) and provides improved capabilities for predicting fire-induced mortality and injury before a fire occurs by...

  5. Firing patterns in the adaptive exponential integrate-and-fire model.

    Science.gov (United States)

    Naud, Richard; Marcille, Nicolas; Clopath, Claudia; Gerstner, Wulfram

    2008-11-01

    For simulations of large spiking neuron networks, an accurate, simple and versatile single-neuron modeling framework is required. Here we explore the versatility of a simple two-equation model: the adaptive exponential integrate-and-fire neuron. We show that this model generates multiple firing patterns depending on the choice of parameter values, and present a phase diagram describing the transition from one firing type to another. We give an analytical criterion to distinguish between continuous adaption, initial bursting, regular bursting and two types of tonic spiking. Also, we report that the deterministic model is capable of producing irregular spiking when stimulated with constant current, indicating low-dimensional chaos. Lastly, the simple model is fitted to real experiments of cortical neurons under step current stimulation. The results provide support for the suitability of simple models such as the adaptive exponential integrate-and-fire neuron for large network simulations.

  6. A comparison of geospatially modeled fire behavior and fire management utility of three data sources in the southeastern United States

    Science.gov (United States)

    LaWen T. Hollingsworth; Laurie L. Kurth; Bernard R. Parresol; Roger D. Ottmar; Susan J. Prichard

    2012-01-01

    Landscape-scale fire behavior analyses are important to inform decisions on resource management projects that meet land management objectives and protect values from adverse consequences of fire. Deterministic and probabilistic geospatial fire behavior analyses are conducted with various modeling systems including FARSITE, FlamMap, FSPro, and Large Fire Simulation...

  7. Integrating remote sensing and terrain data in forest fire modeling

    Science.gov (United States)

    Medler, Michael Johns

    Forest fire policies are changing. Managers now face conflicting imperatives to re-establish pre-suppression fire regimes, while simultaneously preventing resource destruction. They must, therefore, understand the spatial patterns of fires. Geographers can facilitate this understanding by developing new techniques for mapping fire behavior. This dissertation develops such techniques for mapping recent fires and using these maps to calibrate models of potential fire hazards. In so doing, it features techniques that strive to address the inherent complexity of modeling the combinations of variables found in most ecological systems. Image processing techniques were used to stratify the elements of terrain, slope, elevation, and aspect. These stratification images were used to assure sample placement considered the role of terrain in fire behavior. Examination of multiple stratification images indicated samples were placed representatively across a controlled range of scales. The incorporation of terrain data also improved preliminary fire hazard classification accuracy by 40%, compared with remotely sensed data alone. A Kauth-Thomas transformation (KT) of pre-fire and post-fire Thematic Mapper (TM) remotely sensed data produced brightness, greenness, and wetness images. Image subtraction indicated fire induced change in brightness, greenness, and wetness. Field data guided a fuzzy classification of these change images. Because fuzzy classification can characterize a continuum of a phenomena where discrete classification may produce artificial borders, fuzzy classification was found to offer a range of fire severity information unavailable with discrete classification. These mapped fire patterns were used to calibrate a model of fire hazards for the entire mountain range. Pre-fire TM, and a digital elevation model produced a set of co-registered images. Training statistics were developed from 30 polygons associated with the previously mapped fire severity. Fuzzy

  8. Advanced numerical modelling of a fire. Final report

    International Nuclear Information System (INIS)

    Heikkilae, L.; Keski-Rahkonen, O.

    1996-03-01

    Experience and probabilistic risk assessments show that fires present a major hazard in a nuclear power plant (NPP). The PALOME project (1988-92) improved the quality of numerical simulation of fires to make it a useful tool for fire safety analysis. Some of the most advanced zone model fire simulation codes were acquired. The performance of the codes was studied through literature and personal interviews in earlier studies and BRI2 code from the Japanese Building Research Institute was selected for further use. In PALOME 2 project this work was continued. Information obtained from large-scale fire tests at the German HDR facility allowed reliable prediction of the rate of heat release and was used for code validation. BRI2 code was validated particularly by participation in the CEC standard problem 'Prediction of effects caused by a cable fire experiment within the HDR-facility'. Participation in the development of a new field model code SOFIE specifically for fire applications as British-Swedish-Finnish cooperation was one of the goals of the project. SOFIE code was implemented at VTT and the first results of validation simulations were obtained. Well instrumented fire tests on electronic cabinets were carried out to determine source terms for simulation of room fires and to estimate fire spread to adjacent cabinets. The particular aim of this study was to measure the rate of heat release from a fire in an electronic cabinet. From the three tests, differing mainly in the amount of the fire load, data was obtained for source terms in numerical modelling of fires in rooms containing electronic cabinets. On the basis of these tests also a simple natural ventilation model was derived. (19 refs.)

  9. Mathematical modeling of agricultural fires beneath high voltage transmission lines

    International Nuclear Information System (INIS)

    El-Zohri, Emad H.; Shafey, Hamdy M.; Abdel-Salam, M.; Ahmed, A.

    2011-01-01

    This paper presents a mathematical model for agricultural fires based on a multi-phase formulation. The model includes dehydration and pyrolysis of agricultural fuel and pyrolysis products. The model considers a homogeneous distribution of the agricultural solid fuel particles, interacting with the gas flow via source terms. These terms include: drag forces, production of water vapour and pyrolysis products, radiative and convective heat exchange. A multi-phase radiative transfer equation for absorbing-emitting medium is considered to account for the radiative heat exchange between the gas and solid phases of the fire. The main outputs of the present model are most important to study the influence of agricultural fire occurring beneath high voltage transmission lines. The agricultural fire causes a flashover due to the ambient temperature rise and soot accumulation on the insulator of these transmission lines. Numerical results of the present model are obtained for flat grassland fires to study the effects of wind velocity, solid fuel moisture content and ignition length on some selected fire outputs. These outputs include the temperature, velocity, soot volume fraction fields of the gas phase, together with fire propagation rate and flame geometry. The numerical results are compared to the available experimental work in the literature. -- Research highlights: → The model is sensitive to the initial condition of the ignition length affecting the fire propagation rate and width. → The model predicts the effects of both the wind velocity and the fuel moisture content on fire propagation rate, in agreement with the available experimental work in the literature. → The model shows that both the wind velocity and the fuel moisture content are important factors affecting the fire plume thickness, location, and inclination. → The model is able to visualize the flame geometry through tracing radiative heat rates exceeding a threshold value for flame visibility (60 k

  10. FIRE

    International Nuclear Information System (INIS)

    Brtis, J.S.; Hausheer, T.G.

    1990-01-01

    FIRE, a microcomputer based program to assist engineers in reviewing and documenting the fire protection impact of design changes has been developed. Acting as an electronic consultant, FIRE is designed to work with an experienced nuclear system engineer, who may not have any detailed fire protection expertise. FIRE helps the engineer to decide if a modification might adversely affect the fire protection design of the station. Since its first development, FIRE has been customized to reflect the fire protection philosophy of the Commonwealth Edison Company. That program is in early production use. This paper discusses the FIRE program in light of its being a useful application of expert system technologies in the power industry

  11. Modeling fire and other disturbance processes using LANDIS

    Science.gov (United States)

    Stephen R. Shifley; Jian Yang; Hong He

    2009-01-01

    LANDIS is a landscape decision support tool that models spatial relationships to help managers and planners examine the large-scale, long-term, cumulative effects of succession, harvesting, wildfire, prescribed fire, insects, and disease. It can operate on forest landscapes from a few thousand to a few million acres in extent. Fire modeling capabilities in LANDIS are...

  12. Integrating models to predict regional haze from wildland fire.

    Science.gov (United States)

    D. McKenzie; S.M. O' Neill; N. Larkin; R.A. Norheim

    2006-01-01

    Visibility impairment from regional haze is a significant problem throughout the continental United States. A substantial portion of regional haze is produced by smoke from prescribed and wildland fires. Here we describe the integration of four simulation models, an array of GIS raster layers, and a set of algorithms for fire-danger calculations into a modeling...

  13. Deriving forest fire ignition risk with biogeochemical process modelling.

    Science.gov (United States)

    Eastaugh, C S; Hasenauer, H

    2014-05-01

    Climate impacts the growth of trees and also affects disturbance regimes such as wildfire frequency. The European Alps have warmed considerably over the past half-century, but incomplete records make it difficult to definitively link alpine wildfire to climate change. Complicating this is the influence of forest composition and fuel loading on fire ignition risk, which is not considered by purely meteorological risk indices. Biogeochemical forest growth models track several variables that may be used as proxies for fire ignition risk. This study assesses the usefulness of the ecophysiological model BIOME-BGC's 'soil water' and 'labile litter carbon' variables in predicting fire ignition. A brief application case examines historic fire occurrence trends over pre-defined regions of Austria from 1960 to 2008. Results show that summer fire ignition risk is largely a function of low soil moisture, while winter fire ignitions are linked to the mass of volatile litter and atmospheric dryness.

  14. Numerical modelling of methanol liquid pool fires

    Science.gov (United States)

    Prasad, Kuldeep; Li, Chiping; Kailasanath, K.; Ndubizu, Chuka; Ananth, Ramagopal; Tatem, P. A.

    1999-12-01

    The focus of this paper is on numerical modelling of methanol liquid pool fires. A mathematical model is first developed to describe the evaporation and burning of a two-dimensional or axisymmetric pool containing pure liquid methanol. Then, the complete set of unsteady, compressible Navier-Stokes equations for reactive flows are solved in the gas phase to describe the convection of the fuel gases away from the pool surface, diffusion of the gases into the surrounding air and the oxidation of the fuel into product species. Heat transfer into the liquid pool and the metal container through conduction, convection and radiation are modelled by solving a modified form of the energy equation. Clausius-Clapeyron relationships are invoked to model the evaporation rate of a two-dimensional pool of pure liquid methanol. The governing equations along with appropriate boundary and interface conditions are solved using the flux-corrected transport algorithm. Numerical results exhibit a flame structure that compares well with experimental observations. Temperature profiles and burning rates were found to compare favourably with experimental data from single- and three-compartment laboratory burners. The model predicts a puffing frequency of approximately 12 Hz for a 1 cm diameter methanol pool in the absence of any air co-flow. It is also observed that increasing the air co-flow velocity helps in stabilizing the diffusion flame, by pushing the vortical structures away from the flame region.

  15. IMPROVING THE INTEROPERABILITY OF DISASTER MODELS: A CASE STUDY OF PROPOSING FIREML FOR FOREST FIRE MODEL

    Directory of Open Access Journals (Sweden)

    W. Jiang

    2018-04-01

    Full Text Available This paper presents a new standardized data format named Fire Markup Language (FireML, extended by the Geography Markup Language (GML of OGC, to elaborate upon the fire hazard model. The proposed FireML is able to standardize the input and output documents of a fire model for effectively communicating with different disaster management systems to ensure a good interoperability. To demonstrate the usage of FireML and testify its feasibility, an adopted forest fire spread model being compatible with FireML is described. And a 3DGIS disaster management system is developed to simulate the dynamic procedure of forest fire spread with the defined FireML documents. The proposed approach will enlighten ones who work on other disaster models' standardization work.

  16. Improving the Interoperability of Disaster Models: a Case Study of Proposing Fireml for Forest Fire Model

    Science.gov (United States)

    Jiang, W.; Wang, F.; Meng, Q.; Li, Z.; Liu, B.; Zheng, X.

    2018-04-01

    This paper presents a new standardized data format named Fire Markup Language (FireML), extended by the Geography Markup Language (GML) of OGC, to elaborate upon the fire hazard model. The proposed FireML is able to standardize the input and output documents of a fire model for effectively communicating with different disaster management systems to ensure a good interoperability. To demonstrate the usage of FireML and testify its feasibility, an adopted forest fire spread model being compatible with FireML is described. And a 3DGIS disaster management system is developed to simulate the dynamic procedure of forest fire spread with the defined FireML documents. The proposed approach will enlighten ones who work on other disaster models' standardization work.

  17. Modeling post-fire hydro-geomorphic recovery in the Waldo Canyon Fire

    Science.gov (United States)

    Kinoshita, Alicia; Nourbakhshbeidokhti, Samira; Chin, Anne

    2016-04-01

    Wildfire can have significant impacts on watershed hydrology and geomorphology by changing soil properties and removing vegetation, often increasing runoff and soil erosion and deposition, debris flows, and flooding. Watershed systems may take several years or longer to recover. During this time, post-fire channel changes have the potential to alter hydraulics that influence characteristics such as time of concentration and increase time to peak flow, flow capacity, and velocity. Using the case of the 2012 Waldo Canyon Fire in Colorado (USA), this research will leverage field-based surveys and terrestrial Light Detection and Ranging (LiDAR) data to parameterize KINEROS2 (KINematic runoff and EROSion), an event oriented, physically-based watershed runoff and erosion model. We will use the Automated Geospatial Watershed Assessment (AGWA) tool, which is a GIS-based hydrologic modeling tool that uses commonly available GIS data layers to parameterize, execute, and spatially visualize runoff and sediment yield for watersheds impacted by the Waldo Canyon Fire. Specifically, two models are developed, an unburned (Bear Creek) and burned (Williams) watershed. The models will simulate burn severity and treatment conditions. Field data will be used to validate the burned watersheds for pre- and post-fire changes in infiltration, runoff, peak flow, sediment yield, and sediment discharge. Spatial modeling will provide insight into post-fire patterns for varying treatment, burn severity, and climate scenarios. Results will also provide post-fire managers with improved hydro-geomorphic modeling and prediction tools for water resources management and mitigation efforts.

  18. Modeling the spatial distribution of forest crown biomass and effects on fire behavior with FUEL3D and WFDS

    Science.gov (United States)

    Russell A. Parsons; William Mell; Peter McCauley

    2010-01-01

    Crown fire poses challenges to fire managers and can endanger fire fighters. Understanding of how fire interacts with tree crowns is essential to informed decisions about crown fire. Current operational crown fire predictions in the United States assume homogeneous crown fuels. While a new class of research fire models, which model fire behavior with computational...

  19. Crossing boundaries in a collaborative modeling workspace

    Science.gov (United States)

    Morisette, Jeffrey T.; Cravens, Amanda; Miller, Brian W.; Talbert, Marian; Talbert, Colin; Jarnevich, Catherine S.; Fink, Michelle; Decker, Karin; Odell, Eric

    2017-01-01

    There is substantial literature on the importance of bridging across disciplinary and science–management boundaries. One of the ways commonly suggested to cross boundaries is for participants from both sides of the boundary to jointly produce information (i.e., knowledge co-production). But simply providing tools or bringing people together in the same room is not sufficient. Here we present a case study documenting the mechanisms by which managers and scientists collaborated to incorporate climate change projections into Colorado’s State Wildlife Action Plan. A critical component of the project was the use of a collaborative modeling and visualization workspace: the U.S. Geological Survey’s Resource for Advanced Modeling (RAM). Using video analysis and pre/post surveys from this case study, we examine how the RAM facilitated cognitive and social processes that co-produced a more salient and credible end product. This case provides practical suggestions to scientists and practitioners who want to implement actionable science.

  20. Fire and Heat Spreading Model Based on Cellular Automata Theory

    Science.gov (United States)

    Samartsev, A. A.; Rezchikov, A. F.; Kushnikov, V. A.; Ivashchenko, V. A.; Bogomolov, A. S.; Filimonyuk, L. Yu; Dolinina, O. N.; Kushnikov, O. V.; Shulga, T. E.; Tverdokhlebov, V. A.; Fominykh, D. S.

    2018-05-01

    The distinctive feature of the proposed fire and heat spreading model in premises is the reduction of the computational complexity due to the use of the theory of cellular automata with probability rules of behavior. The possibilities and prospects of using this model in practice are noted. The proposed model has a simple mechanism of integration with agent-based evacuation models. The joint use of these models could improve floor plans and reduce the time of evacuation from premises during fires.

  1. Simulation as a vehicle for enhancing collaborative practice models.

    Science.gov (United States)

    Jeffries, Pamela R; McNelis, Angela M; Wheeler, Corinne A

    2008-12-01

    Clinical simulation used in a collaborative practice approach is a powerful tool to prepare health care providers for shared responsibility for patient care. Clinical simulations are being used increasingly in professional curricula to prepare providers for quality practice. Little is known, however, about how these simulations can be used to foster collaborative practice across disciplines. This article provides an overview of what simulation is, what collaborative practice models are, and how to set up a model using simulations. An example of a collaborative practice model is presented, and nursing implications of using a collaborative practice model in simulations are discussed.

  2. Modeling of air toxics from hydrocarbon pool fires

    International Nuclear Information System (INIS)

    Harvey, K.A.; Aydil, M.L.; Barone, J.B.

    1996-01-01

    While there is guidance for estimating the radiation hazards of fires (ARCHIE), there is little guidance on modeling the dispersion of hazardous materials from fires. The objective of this paper is to provide a review of the methodology used for modeling the impacts of liquid hydrocarbon pool fires. The required input variables for modeling of hydrocarbon pool fires include emission strength, emission duration, and dispersion characteristics. Methods for predicting the products of combustion including the use of literature values, test data, and thermodynamic equilibrium calculations are discussed. The use of energy balances coupled to radiative heat transfer calculations are presented as a method for determining flame temperature. Fire modeling literature is reviewed in order to determine other source release variables such as mass burn rate and duration and flame geometry

  3. Building a Model of Successful Collaborative Learning for Company Innovativeness

    Directory of Open Access Journals (Sweden)

    Agata Sudolska

    2014-01-01

    Full Text Available The aim of the paper is to develop a model of successful collaborative learning for company innovativeness. First of all, the paper explores the issue of inter-firm learning, focusing its attention on collaborative learning. Secondly, inter-firm learning relationships are considered. Thirdly, the ex ante conditions of collaborative learning and the intra-organizational enhancers of inter-firm learning processes are studied. Finally, a model of the critical success factors for collaborative learning is developed.

  4. Addressing contrasting cognitive models in scientific collaboration

    Science.gov (United States)

    Diviacco, P.

    2012-04-01

    If the social aspects of scientific communities and their internal dynamics is starting to be recognized and acknowledged in the everyday lives of scientists, it is rather difficult for them to find tools that could support their activities consistently with this perspective. Issues span from gathering researchers to mutual awareness, from information sharing to building meaning, with the last one being particularly critical in research fields as the geo-sciences, that deal with the reconstruction of unique, often non-reproducible, and contingent processes. Reasoning here is, in fact, mainly abductive, allowing multiple and concurrent explanations for the same phenomenon to coexist. Scientists bias one hypothesis over another not only on strictly logical but also on sociological motivations. Following a vision, scientists tend to evolve and isolate themselves from other scientists creating communities characterized by different cognitive models, so that after some time these become incompatible and scientists stop understanding each other. We address these problems as a communication issue so that the classic distinction into three levels (syntactic, semantic and pragmatic) can be used. At the syntactic level, we highlight non-technical obstacles that condition interoperability and data availability and transparency. At the semantic level, possible incompatibilities of cognitive models are particularly evident, so that using ontologies, cross-domain reconciliation should be applied. This is a very difficult task to perform since the projection of knowledge by scientists, in the designated community, is political and thus can create a lot of tension. The strategy we propose to overcome these issues pertains to pragmatics, in the sense that it is intended to acknowledge the cultural and personal factors each partner brings into the collaboration and is based on the idea that meaning should remain a flexible and contingent representation of possibly divergent views

  5. FIREPLUME model for plume dispersion from fires: Application to uranium hexafluoride cylinder fires

    International Nuclear Information System (INIS)

    Brown, D.F.; Dunn, W.E.

    1997-06-01

    This report provides basic documentation of the FIREPLUME model and discusses its application to the prediction of health impacts resulting from releases of uranium hexafluoride (UF 6 ) in fires. The model application outlined in this report was conducted for the Draft Programmatic Environmental Impact Statement for Alternative Strategies for the Long-Term Management and Use of Depleted UF 6 . The FIREPLUME model is an advanced stochastic model for atmospheric plume dispersion that predicts the downwind consequences of a release of toxic materials from an explosion or a fire. The model is based on the nonbuoyant atmospheric dispersion model MCLDM (Monte Carlo Lagrangian Dispersion Model), which has been shown to be consistent with available laboratory and field data. The inclusion of buoyancy and the addition of a postprocessor to evaluate time-varying concentrations lead to the current model. The FIREPLUME model, as applied to fire-related UF 6 cylinder releases, accounts for three phases of release and dispersion. The first phase of release involves the hydraulic rupture of the cylinder due to heating of the UF 6 in the fire. The second phase involves the emission of material into the burning fire, and the third phase involves the emission of material after the fire has died during the cool-down period. The model predicts the downwind concentration of the material as a function of time at any point downwind at or above the ground. All together, five fire-related release scenarios are examined in this report. For each scenario, downwind concentrations of the UF 6 reaction products, uranyl fluoride and hydrogen fluoride, are provided for two meteorological conditions: (1) D stability with a 4-m/s wind speed, and (2) F stability with a 1-m/s wind speed

  6. Process and data fragmentation-oriented enterprise network integration with collaboration modelling and collaboration agents

    Science.gov (United States)

    Li, Qing; Wang, Ze-yuan; Cao, Zhi-chao; Du, Rui-yang; Luo, Hao

    2015-08-01

    With the process of globalisation and the development of management models and information technology, enterprise cooperation and collaboration has developed from intra-enterprise integration, outsourcing and inter-enterprise integration, and supply chain management, to virtual enterprises and enterprise networks. Some midfielder enterprises begin to serve for different supply chains. Therefore, they combine related supply chains into a complex enterprise network. The main challenges for enterprise network's integration and collaboration are business process and data fragmentation beyond organisational boundaries. This paper reviews the requirements of enterprise network's integration and collaboration, as well as the development of new information technologies. Based on service-oriented architecture (SOA), collaboration modelling and collaboration agents are introduced to solve problems of collaborative management for service convergence under the condition of process and data fragmentation. A model-driven methodology is developed to design and deploy the integrating framework. An industrial experiment is designed and implemented to illustrate the usage of developed technologies in this paper.

  7. Application of fire and evacuation models in evaluation of fire safety in railway tunnels

    Science.gov (United States)

    Cábová, Kamila; Apeltauer, Tomáš; Okřinová, Petra; Wald, František

    2017-09-01

    The paper describes an application of numerical simulation of fire dynamics and evacuation of people in a tunnel. The software tool Fire Dynamics Simulator is used to simulate temperature resolution and development of smoke in a railway tunnel. Comparing to temperature curves which are usually used in the design stage results of the model show that the numerical model gives lower temperature of hot smoke layer. Outputs of the numerical simulation of fire also enable to improve models of evacuation of people during fires in tunnels. In the presented study the calculated high of smoke layer in the tunnel is in 10 min after the fire ignition lower than the level of 2.2 m which is considered as the maximal limit for safe evacuation. Simulation of the evacuation process in bigger scale together with fire dynamics can provide very valuable information about important security conditions like Available Safe Evacuation Time (ASET) vs Required Safe Evacuation Time (RSET). On given example in software EXODUS the paper summarizes selected results of evacuation model which should be in mind of a designer when preparing an evacuation plan.

  8. Modeling wind adjustment factor and midflame wind speed for Rothermel's surface fire spread model

    Science.gov (United States)

    Patricia L. Andrews

    2012-01-01

    Rothermel's surface fire spread model was developed to use a value for the wind speed that affects surface fire, called midflame wind speed. Models have been developed to adjust 20-ft wind speed to midflame wind speed for sheltered and unsheltered surface fuel. In this report, Wind Adjustment Factor (WAF) model equations are given, and the BehavePlus fire modeling...

  9. Modeling fire susceptibility to delineate wildland-urban interface for municipal-scale fire risk management.

    Science.gov (United States)

    Whitman, Ellen; Rapaport, Eric; Sherren, Kate

    2013-12-01

    The wildland-urban interface (WUI) is the region where development meets and intermingles with wildlands. The WUI has an elevated fire risk due to the proximity of development and residents to wildlands with natural wildfire regimes. Existing methods of delineating WUI are typically applied over a large region, use proxies for risk, and do not consider site-specific fire hazard drivers. While these models are appropriate for federal and provincial risk management, municipal managers require models intended for smaller regions. The model developed here uses the Burn-P3 fire behavior model to model WUI from local fire susceptibility (FS) in two study communities. Forest fuel code (FFC) maps for the study communities were modified using remote sensing data to produce detailed forest edges, including ladder fuels, update data currency, and add buildings and roads. The modified FFC maps used in Burn-P3 produced bimodal FS distributions for each community. The WUI in these communities was delineated as areas within community bounds where FS was greater than or equal to -1 SD from the mean FS value ([Formula: see text]), which fell in the trough of the bimodal distribution. The WUI so delineated conformed to the definition of WUI. This model extends WUI modeling for broader risk management initiatives for municipal management of risk, as it (a) considers site-specific drivers of fire behavior; (b) models risk, represented by WUI, specific to a community; and, (c) does not use proxies for risk.

  10. Experimental and numerical modeling of shrub crown fire initiation

    Science.gov (United States)

    Watcharapong Tachajapong; Jesse Lozano; Shakar Mahalingam; Xiangyang Zhou; David Weise

    2009-01-01

    The transition of fire from dry surface fuels to wet shrub crown fuels was studied using laboratory experiments and a simple physical model to gain a better understanding of the transition process. In the experiments, we investigated the effects of varying vertical distances between surface and crown fuels (crown base height), and of the wind speed on crown fire...

  11. Mathematical modelling of fire in forced ventilated enclosures

    International Nuclear Information System (INIS)

    Cox, G.; Kumar, S.

    1985-01-01

    The application of a computer fire simulation model to the prediction of conditions in a forced ventilated experimental fire test cell at the Lawrence Livermore National Laboratory is discussed. Comparisons between theoretical and experimental determinations are shown to be in reasonable agreement and areas requiring further research indicated

  12. [Collaboration among health professionals (II). Usefulness of a model].

    Science.gov (United States)

    D'Amour, Danielle; San Martín Rodríguez, Leticia

    2006-09-01

    This second article provides a model which helps one to better understand the process of collaboration by interprofessional teams and makes it possible to evaluate the quality of the aforementioned collaboration. To this end, the authors first present a structural model of inter-professional collaboration followed by a typology of collaboration which is derived from the functionality of said model. This model is composed by four interrelated dimensions; the functionality of these has given rise to a typology of collaboration at three intensities: in action, in construction and collaboration during inertia. The model and the typology constitute a useful tool for managers and for health professionals since they help to better understand, manage and develop collaboration among the distinct professionals inside of the same organization as among those who belong to distinct organizations.

  13. Collaborative Inquiry Learning: Models, tools, and challenges

    Science.gov (United States)

    Bell, Thorsten; Urhahne, Detlef; Schanze, Sascha; Ploetzner, Rolf

    2010-02-01

    Collaborative inquiry learning is one of the most challenging and exciting ventures for today's schools. It aims at bringing a new and promising culture of teaching and learning into the classroom where students in groups engage in self-regulated learning activities supported by the teacher. It is expected that this way of learning fosters students' motivation and interest in science, that they learn to perform steps of inquiry similar to scientists and that they gain knowledge on scientific processes. Starting from general pedagogical reflections and science standards, the article reviews some prominent models of inquiry learning. This comparison results in a set of inquiry processes being the basis for cooperation in the scientific network NetCoIL. Inquiry learning is conceived in several ways with emphasis on different processes. For an illustration of the spectrum, some main conceptions of inquiry and their focuses are described. In the next step, the article describes exemplary computer tools and environments from within and outside the NetCoIL network that were designed to support processes of collaborative inquiry learning. These tools are analysed by describing their functionalities as well as effects on student learning known from the literature. The article closes with challenges for further developments elaborated by the NetCoIL network.

  14. Collaborative Rural Healthcare Network: A Conceptual Model

    Directory of Open Access Journals (Sweden)

    U. Raja

    2011-07-01

    Full Text Available Healthcare is a critical issue in rural communities throughout the world. Provision of timely and cost effective health care in these communities is a challenge since it is coupled with a lack of adequate infrastructure and manpower support. Twenty percent of the United States of America‘s population resides in rural communities, i.e., 59 million people; however, only nine percent of the nation’s physicians practice in rural communities. Shortage of health care personnel and the lack of equipment and facilities often force rural residents to travel long distances to receive needed medical treatment. Researchers and practitioners are in search of solutions to address these unique challenges. In this research, we present a proposed collaborative model of a health information system for rural communities and the challenges and opportunities of this global issue.

  15. Modeling fuels and fire effects in 3D: Model description and applications

    Science.gov (United States)

    Francois Pimont; Russell Parsons; Eric Rigolot; Francois de Coligny; Jean-Luc Dupuy; Philippe Dreyfus; Rodman R. Linn

    2016-01-01

    Scientists and managers critically need ways to assess how fuel treatments alter fire behavior, yet few tools currently exist for this purpose.We present a spatially-explicit-fuel-modeling system, FuelManager, which models fuels, vegetation growth, fire behavior (using a physics-based model, FIRETEC), and fire effects. FuelManager's flexible approach facilitates...

  16. Foundations for a multiscale collaborative Earth model

    KAUST Repository

    Afanasiev, M.

    2015-11-11

    We present a computational framework for the assimilation of local to global seismic data into a consistent model describing Earth structure on all seismically accessible scales. This Collaborative Seismic Earth Model (CSEM) is designed to meet the following requirements: (i) Flexible geometric parametrization, capable of capturing topography and bathymetry, as well as all aspects of potentially resolvable structure, including small-scale heterogeneities and deformations of internal discontinuities. (ii) Independence of any particular wave equation solver, in order to enable the combination of inversion techniques suitable for different types of seismic data. (iii) Physical parametrization that allows for full anisotropy and for variations in attenuation and density. While not all of these parameters are always resolvable, the assimilation of data that constrain any parameter subset should be possible. (iv) Ability to accommodate successive refinements through the incorporation of updates on any scale as new data or inversion techniques become available. (v) Enable collaborative Earth model construction. The structure of the initial CSEM is represented on a variable-resolution tetrahedral mesh. It is assembled from a long-wavelength 3-D global model into which several regional-scale tomographies are embedded. We illustrate the CSEM workflow of successive updating with two examples from Japan and the Western Mediterranean, where we constrain smaller scale structure using full-waveform inversion. Furthermore, we demonstrate the ability of the CSEM to act as a vehicle for the combination of different tomographic techniques with a joint full-waveform and traveltime ray tomography of Europe. This combination broadens the exploitable frequency range of the individual techniques, thereby improving resolution. We perform two iterations of a whole-Earth full-waveform inversion using a long-period reference data set from 225 globally recorded earthquakes. At this early stage

  17. Use of numerical modeling in design for co-firing biomass in wall-fired burners

    DEFF Research Database (Denmark)

    Yin, Chungen; Rosendahl, Lasse Aistrup; Kær, Søren Knudsen

    2004-01-01

    modification to the motion and reaction due to their non-sphericity. The simulation results show a big difference between the two cases and indicate it is very significant to take into account the non-sphericity of biomass particles in order to model biomass combustion more accurately. Methods to improve...... of numerical modeling. The models currently used to predict solid fuel combustion rely on a spherical particle shape assumption, which may deviate a lot from reality for big biomass particles. A sphere gives a minimum in terms of the surface-area-to-volume ratio, which impacts significantly both motion...... and reaction of a particle. To better understand biomass combustion and thus improve the design for co-firing biomass in wall-fired burners, non-sphericity of biomass particles is considered. To ease comparison, two cases are numerically studied in a 10m long gas/biomass co-fired burner model. (1) The biomass...

  18. Related work on reference modeling for collaborative networks

    NARCIS (Netherlands)

    Afsarmanesh, H.; Camarinha-Matos, L.M.; Camarinha-Matos, L.M.; Afsarmanesh, H.

    2008-01-01

    Several international research and development initiatives have led to development of models for organizations and organization interactions. These models and their approaches constitute a background for development of reference models for collaborative networks. A brief survey of work on modeling

  19. Model of fire spread around Krsko Power Plant

    International Nuclear Information System (INIS)

    Vidmar, P.; Petelin, S.

    2001-01-01

    The idea behind the article is how to define fire behaviour. The work is based on an analytical study of fire origin, its development and spread. The study is based on thermodynamics, heat transfer and the study of hydrodynamics and combustion, which represent the bases of fire dynamics. The article shows a practical example of a leak of hazardous chemicals from a tank. Because of the inflammability of the fluid, fire may start. We have tried to model fire propagation around the Krsko power plant, and show what extended surrounding area could be affected. The model also considers weather conditions, in particular wind speed and direction. For this purpose we have used the computer code Safer Trace, which is based on zone models. That means that phenomena are described by physical and empirical equations. An imperfection in this computer code is the inability to consider ground topology. However in the case of the Krsko power plant, topology is not so important, as the plan is located in a relatively flat region. Mathematical models are presented. They show the propagation of hazardous fluid in the environment considering meteorological data. The work also shows which data are essential to define fire spread and shows the main considerations of Probabilistic Safety Assessment for external fire event.(author)

  20. Collaboration

    Science.gov (United States)

    King, Michelle L.

    2010-01-01

    This article explores collaboration between library media educators and regular classroom teachers. The article focuses on the context of the issue, positions on the issue, the impact of collaboration, and how to implement effective collaboration into the school system. Various books and professional journals are used to support conclusions…

  1. Modelling methods for co-fired pulverised fuel furnaces

    Energy Technology Data Exchange (ETDEWEB)

    L. Ma; M. Gharebaghi; R. Porter; M. Pourkashanian; J.M. Jones; A. Williams [University of Leeds, Leeds (United Kingdom). Energy and Resources Research Institute

    2009-12-15

    Co-firing of biomass and coal can be beneficial in reducing the carbon footprint of energy production. Accurate modelling of co-fired furnaces is essential to discover potential problems that may occur during biomass firing and to mitigate potential negative effects of biomass fuels, including lower efficiency due to lower burnout and NOx formation issues. Existing coal combustion models should be modified to increase reliability of predictions for biomass, including factors such as increased drag due to non-spherical particle sizes and accounting for organic compounds and the effects they have on NOx emission. Detailed biomass co-firing models have been developed and tested for a range of biomass fuels and show promising results. 32 refs., 4 figs., 3 tabs.

  2. Fire Modeling Institute: FY2012 Annual Report: Bridging scientists and managers

    Science.gov (United States)

    Robin J. Innes

    2013-01-01

    The Fire Modeling Institute (FMI) brings the best available fire and fuel science and technology developed throughout the research community to bear in fire-related management issues. Although located within the Fire, Fuel, and Smoke Science Program of the U.S. Forest Service Rocky Mountain Research Station, FMI is a national and international resource, serving fire...

  3. Modeling and Analysis of Realistic Fire Scenarios in Spacecraft

    Science.gov (United States)

    Brooker, J. E.; Dietrich, D. L.; Gokoglu, S. A.; Urban, D. L.; Ruff, G. A.

    2015-01-01

    An accidental fire inside a spacecraft is an unlikely, but very real emergency situation that can easily have dire consequences. While much has been learned over the past 25+ years of dedicated research on flame behavior in microgravity, a quantitative understanding of the initiation, spread, detection and extinguishment of a realistic fire aboard a spacecraft is lacking. Virtually all combustion experiments in microgravity have been small-scale, by necessity (hardware limitations in ground-based facilities and safety concerns in space-based facilities). Large-scale, realistic fire experiments are unlikely for the foreseeable future (unlike in terrestrial situations). Therefore, NASA will have to rely on scale modeling, extrapolation of small-scale experiments and detailed numerical modeling to provide the data necessary for vehicle and safety system design. This paper presents the results of parallel efforts to better model the initiation, spread, detection and extinguishment of fires aboard spacecraft. The first is a detailed numerical model using the freely available Fire Dynamics Simulator (FDS). FDS is a CFD code that numerically solves a large eddy simulation form of the Navier-Stokes equations. FDS provides a detailed treatment of the smoke and energy transport from a fire. The simulations provide a wealth of information, but are computationally intensive and not suitable for parametric studies where the detailed treatment of the mass and energy transport are unnecessary. The second path extends a model previously documented at ICES meetings that attempted to predict maximum survivable fires aboard space-craft. This one-dimensional model implies the heat and mass transfer as well as toxic species production from a fire. These simplifications result in a code that is faster and more suitable for parametric studies (having already been used to help in the hatch design of the Multi-Purpose Crew Vehicle, MPCV).

  4. A Model Collaborative Platform for Geoscience Education

    Science.gov (United States)

    Fox, S.; Manduca, C. A.; Iverson, E. A.

    2012-12-01

    generated author profiles highlight the contributions an individual has made through any of the projects with an option for customization by the author. An overarching portal site provides a unified view of resources within this diverse set of geoscience education projects. The SERC CMS provides a common platform upon which individual projects can build their own identities, while allowing cross-project pollination and synergies to be realized without significant extra investment by each project. This is a sustainable model for a collaborative platform that takes advantage of the energy and resources of individual projects to advance larger community goals.

  5. Proven collaboration model for impact generating research with universities

    CSIR Research Space (South Africa)

    Bezuidenhout, DF

    2010-09-01

    Full Text Available -optics, image processing and computer vision. This paper presents the research collaboration model with universities that has ensured the PRISM programme's success. It is shown that this collaboration model has resulted in a pipeline of highly-skilled people...

  6. Transforming Collaborative Process Models into Interface Process Models by Applying an MDA Approach

    Science.gov (United States)

    Lazarte, Ivanna M.; Chiotti, Omar; Villarreal, Pablo D.

    Collaborative business models among enterprises require defining collaborative business processes. Enterprises implement B2B collaborations to execute these processes. In B2B collaborations the integration and interoperability of processes and systems of the enterprises are required to support the execution of collaborative processes. From a collaborative process model, which describes the global view of the enterprise interactions, each enterprise must define the interface process that represents the role it performs in the collaborative process in order to implement the process in a Business Process Management System. Hence, in this work we propose a method for the automatic generation of the interface process model of each enterprise from a collaborative process model. This method is based on a Model-Driven Architecture to transform collaborative process models into interface process models. By applying this method, interface processes are guaranteed to be interoperable and defined according to a collaborative process.

  7. [Measurement model of carbon emission from forest fire: a review].

    Science.gov (United States)

    Hu, Hai-Qing; Wei, Shu-Jing; Jin, Sen; Sun, Long

    2012-05-01

    Forest fire is the main disturbance factor for forest ecosystem, and an important pathway of the decrease of vegetation- and soil carbon storage. Large amount of carbonaceous gases in forest fire can release into atmosphere, giving remarkable impacts on the atmospheric carbon balance and global climate change. To scientifically and effectively measure the carbonaceous gases emission from forest fire is of importance in understanding the significance of forest fire in the carbon balance and climate change. This paper reviewed the research progress in the measurement model of carbon emission from forest fire, which covered three critical issues, i. e., measurement methods of forest fire-induced total carbon emission and carbonaceous gases emission, affecting factors and measurement parameters of measurement model, and cause analysis of the uncertainty in the measurement of the carbon emissions. Three path selections to improve the quantitative measurement of the carbon emissions were proposed, i. e., using high resolution remote sensing data and improving algorithm and estimation accuracy of burned area in combining with effective fuel measurement model to improve the accuracy of the estimated fuel load, using high resolution remote sensing images combined with indoor controlled environment experiments, field measurements, and field ground surveys to determine the combustion efficiency, and combining indoor controlled environment experiments with field air sampling to determine the emission factors and emission ratio.

  8. A comparison of geospatially modeled fire behavior and potential application to fire and fuels management for the Savannah River Site.

    Energy Technology Data Exchange (ETDEWEB)

    Kurth, Laurie; Hollingsworth, LaWen; Shea, Dan

    2011-12-20

    This study evaluates modeled fire behavior for the Savannah River Site in the Atlantic Coastal Plain of the southeastern U.S. using three data sources: FCCS, LANDFIRE, and SWRA. The Fuel Characteristic Classification System (FCCS) was used to build fuelbeds from intensive field sampling of 629 plots. Custom fire behavior fuel models were derived from these fuelbeds. LANDFIRE developed surface fire behavior fuel models and canopy attributes for the U.S. using satellite imagery informed by field data. The Southern Wildfire Risk Assessment (SWRA) developed surface fire behavior fuel models and canopy cover for the southeastern U.S. using satellite imagery.

  9. Collaborative Art Practices in HE: Mapping and Developing Pedagogical Models

    OpenAIRE

    Wilsmore, R; Alix, C; Dobson, E; University of Huddersfield; University of Hull; University of York St John; The Higher Education Academy; Palatine

    2010-01-01

    This project asks ‘How is interdisciplinary collaboration "taught" in HE institutions?’ and ‘What pedagogical models can be identified and developed?’\\ud Performing and Creative Arts departments in HE institutions engage students in collaborative practice within a singular discipline or across disciplines, through interdisciplinary or hybridised art forms, as curricula or extra-curricula activity. Where students are engaged with interdisciplinary collaboration within the curriculum, tuition m...

  10. On enhancing on-line collaboration using fuzzy logic modeling

    Directory of Open Access Journals (Sweden)

    Leontios J. Hadjileontiadis

    2004-04-01

    Full Text Available Web-based collaboration calls for professional skills and competences to the benefit of the quality of the collaboration and its output. Within this framework, educational virtual environments may provide a means for training upon these skills and in particular the collaborative ones. On the basis of the existing technological means such training may be enhanced even more. Designing considerations towards this direction include the close follow-up of the collaborative activity and provision of support grounded upon a pedagogical background. To this vein, a fuzzy logic-based expert system, namely Collaboration/Reflection-Fuzzy Inference System (C/R-FIS, is presented in this paper. By means of interconnected FISs, the C/R-FIS expert system automatically evaluates the collaborative activity of two peers, during their asynchronous, written, web-based collaboration. This information is used for the provision of adaptive support to peers during their collaboration, towards equilibrium of their collaborative activity. In particular, this enhanced formative feedback aims at diminishing the possible dissonance between the individual collaborative skills by challenging self-adjustment procedures. The proposed model extents the evaluation system of a web-based collaborative tool namely Lin2k, which has served as a test-bed for the C/R-FIS experimental use. Results from its experimental use have proved the potentiality of the proposed model to significantly contribute to the enhancement of the collaborative activity and its transferability to other collaborative learning contexts, such as medicine, environmental engineering, law, and music education.

  11. Quantifying the role of fire in the Earth system – Part 1: Improved global fire modeling in the Community Earth System Model (CESM1)

    OpenAIRE

    F. Li; S. Levis; D. S. Ward

    2013-01-01

    Modeling fire as an integral part of an Earth system model (ESM) is vital for quantifying and understanding fire–climate–vegetation interactions on a global scale and from an Earth system perspective. In this study, we introduce to the Community Earth System Model (CESM) the new global fire parameterization proposed by Li et al. (2012a, b), now with a more realistic representation of the anthropogenic impacts on fires, with a parameterization of peat fires, and with other minor modifications....

  12. Systems and models of fire blight (Erwinia amylovora prediction

    Directory of Open Access Journals (Sweden)

    Krzysztof Kielak

    2013-12-01

    Full Text Available The paper presents fire blight prediction models and systems, developed in Europe (system Billing - versions: BOS, BRS, BIS95 and originated from this system: Firescreen, FEUERBRA and ANLAFBRA and in United States (Californian system, model Maryblyt and system Cougarblight. Use of above models and systems in various climatic-geographic conditions and comparison of obtained prognostic data to real fire blight occurrence is reviewed. The newest trends in research on improvement of prognostic analyses parameters with their adjustment to particular conditions and consideration of infection source occurrence are also presented.

  13. Business Process Modeling Languages Supporting Collaborative Networks

    NARCIS (Netherlands)

    Soleimani Malekan, H.; Afsarmanesh, H.; Hammoudi, S.; Maciaszek, L.A.; Cordeiro, J.; Dietz, J.L.G.

    2013-01-01

    Formalizing the definition of Business Processes (BPs) performed within each enterprise is fundamental for effective deployment of their competencies and capabilities within Collaborative Networks (CN). In our approach, every enterprise in the CN is represented by its set of BPs, so that other

  14. A latent model for collaborative filtering

    DEFF Research Database (Denmark)

    Langseth, Helge; Nielsen, Thomas Dyhre

    2012-01-01

    Recommender systems based on collaborative filtering have received a great deal of interest over the last two decades. In particular, recently proposed methods based on dimensionality reduction techniques and using a symmetrical representation of users and items have shown promising results. Foll...

  15. Collaborative Online Teaching: A Model for Gerontological Social Work Education

    Science.gov (United States)

    Fulton, Amy E.; Walsh, Christine A.; Azulai, Anna; Gulbrandsen, Cari; Tong, Hongmei

    2015-01-01

    Social work students and faculty are increasingly embracing online education and collaborative teaching. Yet models to support these activities have not been adequately developed. This paper describes how a team of instructors developed, delivered, and evaluated an undergraduate gerontological social work course using a collaborative online…

  16. Targeting Forest Management through Fire and Erosion Modeling

    Science.gov (United States)

    Elliot, William J.; Miller, Mary Ellen; MacDonald, Lee H.

    2013-04-01

    Forests deliver a number of ecosystem services, including clean water. When forests are disturbed by wildfire, the timing and quantity of runoff can be altered, and the quality can be severely degraded. A modeling study for about 1500 km2 in the Upper Mokelumne River Watershed in California was conducted to determine the risk of wildfire and the associated potential sediment delivery should a wildfire occur, and to calculate the potential reduction in sediment delivery that might result from fuel reduction treatments. The first step was to predict wildfire severity and probability of occurrence under current vegetation conditions with FlamMap fire prediction tool. FlamMap uses current vegetation, topography, and wind characteristics to predict the speed, flame length, and direction of a simulated flame front for each 30-m pixel. As the first step in the erosion modeling, a geospatial interface for the WEPP model (GeoWEPP) was used to delineate approximately 6-ha hillslope polygons for the study area. The flame length values from FlamMap were then aggregated for each hillslope polygon to yield a predicted fire intensity. Fire intensity and pre-fire vegetation conditions were used to estimate fire severity (either unburned, low, moderate or high). The fire severity was combined with soil properties from the STATSGO database to build the vegetation and soil files needed to run WEPP for each polygon. Eight different stochastic climates were generated to account for the weather variability within the basin. A modified batching version of GeoWEPP was used to predict the first-year post-fire sediment yield from each hillslope and subwatershed. Estimated sediment yields ranged from 0 to more than 100 Mg/ha, and were typical of observed values. The polygons that generated the greatest amount of sediment or that were critical for reducing fire spread were identified, and these were "treated" by reducing the amount of fuel available for a wildfire. The erosion associated with

  17. An Agent Based Collaborative Simplification of 3D Mesh Model

    Science.gov (United States)

    Wang, Li-Rong; Yu, Bo; Hagiwara, Ichiro

    Large-volume mesh model faces the challenge in fast rendering and transmission by Internet. The current mesh models obtained by using three-dimensional (3D) scanning technology are usually very large in data volume. This paper develops a mobile agent based collaborative environment on the development platform of mobile-C. Communication among distributed agents includes grasping image of visualized mesh model, annotation to grasped image and instant message. Remote and collaborative simplification can be efficiently conducted by Internet.

  18. Numerical modeling of the effects of fire-induced convection and fire-atmosphere interactions on wildfire spread and fire plume dynamics

    Science.gov (United States)

    Sun, Ruiyu

    It is possible due to present day computing power to produce a fluid dynamical physically-based numerical solution to wildfire behavior, at least in the research mode. This type of wildfire modeling affords a flexibility and produces details that are not available in either current operational wildfire behavior models or field experiments. However before using these models to study wildfire, validation is necessary, and model results need to be systematically and objectively analyzed and compared to real fires. Plume theory and data from the Meteotron experiment, which was specially designed to provide results from measurements for the theoretical study of a convective plume produced by a high heat source at the ground, are used here to evaluate the fire plume properties simulated by two numerical wildfire models, the Fire Dynamics Simulator or FDS, and the Clark coupled atmosphere-fire model. The study indicates that the FDS produces good agreement with the plume theory and the Meteotron results. The study also suggests that the coupled atmosphere-fire model, a less explicit and ideally less computationally demanding model than the FDS; can produce good agreement, but that the agreement is sensitive to the method of putting the energy released from the fire into the atmosphere. The WFDS (Wildfire and wildland-urban interface FDS), an extension of the FDS to the vegetative fuel, and the Australian grass fire experiments are used to evaluate and improve the UULES-wildfire coupled model. Despite the simple fire parameterization in the UULES-wildfire coupled model, the fireline is fairly well predicted in terms of both shape and location in the simulation of Australian grass fire experiment F19. Finally, the UULES-wildfire coupled model is used to examine how the turbulent flow in the atmospheric boundary layer (ABL) affects the growth of the grass fires. The model fires showed significant randomness in fire growth: Fire spread is not deterministic in the ABL, and a

  19. Combining Synchronous and Asynchronous Collaboration within 3D City Models

    Science.gov (United States)

    Klimke, Jan; Döllner, Jürgen

    This paper presents an approach for combining spatially distributed synchronous and asynchronous collaboration within 3D city models. Software applications use these models as additional communication medium to facilitate communication of georeferenced and geospatial information. Collaboration tools should support both the communication with other collaborators and their awareness of the current collaboration context. To support collaborative knowledge construction and gathering, we have designed a collaboration system to facilitate (a) creation of annotations that have 3D references to the virtual 3D city model and (b) collection information about the context in which these annotations are created. Our approach supports synchronous collaboration in connection with the creation of non volatile, precisely georeferenced units of information allow for a comprehensible form of cooperation in spatially distributed settings. Storage and retrieval of this information is provided through a Web Feature Service, which eases integration of collaboration data into existing applications. We further introduce a visualization technique that integrates annotations as complex structured data into the 3D visualization. This avoids media breaks and disruptions in working processes and creates a spatial coherence between annotation and annotated feature or geometry.

  20. Fire danger and fire behavior modeling systems in Australia, Europe, and North America

    Science.gov (United States)

    Francis M. Fujioka; A. Malcolm Gill; Domingos X. Viegas; B. Mike Wotton

    2009-01-01

    Wildland fire occurrence and behavior are complex phenomena involving essentially fuel (vegetation), topography, and weather. Fire managers around the world use a variety of systems to track and predict fire danger and fire behavior, at spatial scales that span from local to global extents, and temporal scales ranging from minutes to seasons. The fire management...

  1. 75 FR 5355 - Notice of Extension of Comment Period for NUREG-1934, Nuclear Power Plant Fire Modeling...

    Science.gov (United States)

    2010-02-02

    ..., Nuclear Power Plant Fire Modeling Application Guide (NPP FIRE MAG), Draft Report for Comment AGENCY... 1019195), Nuclear Power Plant Fire Modeling Application Guide (NPP FIRE MAG), Draft Report for Comment... exists in both the general fire protection and the nuclear power plant (NPP) fire protection communities...

  2. Collaboration and Interconnectivity: Nottinghamshire Fire and Rescue Services and Higher Education Institutions in Nottingham

    Science.gov (United States)

    Murphy, Peter; Greenhalgh, Kirsten; Parkin, Craig

    2013-01-01

    This article will describe the developing relationship between Nottinghamshire Fire and Rescue Services and the two higher education institutions in Nottingham. It will chronicle how a very traditional relationship has been transformed, initially by a simple consultancy project, into a much closer working relationship characterised by a much…

  3. Reference models for forming organisational or collaborative pedagogical best practices

    NARCIS (Netherlands)

    Lee, Chien-Sing; Koper, Rob; Kommers, Piet; Hedberg, John

    2008-01-01

    Lee, Chien-Sing, Koper, R., Kommers, P., & Hedberg, John (Eds.) (2008). Reference models for forming organisational or collaborative pedagogical best practices [special issue]. International Journal of Continuing Engineering Education and Life-Long Learning, 18(1).

  4. Collaborative problem solving with a total quality model.

    Science.gov (United States)

    Volden, C M; Monnig, R

    1993-01-01

    A collaborative problem-solving system committed to the interests of those involved complies with the teachings of the total quality management movement in health care. Deming espoused that any quality system must become an integral part of routine activities. A process that is used consistently in dealing with problems, issues, or conflicts provides a mechanism for accomplishing total quality improvement. The collaborative problem-solving process described here results in quality decision-making. This model incorporates Ishikawa's cause-and-effect (fishbone) diagram, Moore's key causes of conflict, and the steps of the University of North Dakota Conflict Resolution Center's collaborative problem solving model.

  5. Collaborative learning model inquiring based on digital game

    Science.gov (United States)

    Yuan, Jiugen; Xing, Ruonan

    2012-04-01

    With the development of computer education software, digital educational game has become an important part in our life, entertainment and education. Therefore how to make full use of digital game's teaching functions and educate through entertainment has become the focus of current research. The thesis make a connection between educational game and collaborative learning, the current popular teaching model, and concludes digital game-based collaborative learning model combined with teaching practice.

  6. Collaborative data analytics for smart buildings: opportunities and models

    DEFF Research Database (Denmark)

    Lazarova-Molnar, Sanja; Mohamed, Nader

    2018-01-01

    of collaborative data analytics for smart buildings, its benefits, as well as presently possible models of carrying it out. Furthermore, we present a framework for collaborative fault detection and diagnosis as a case of collaborative data analytics for smart buildings. We also provide a preliminary analysis...... of the energy efficiency benefit of such collaborative framework for smart buildings. The result shows that significant energy savings can be achieved for smart buildings using collaborative data analytics.......Smart buildings equipped with state-of-the-art sensors and meters are becoming more common. Large quantities of data are being collected by these devices. For a single building to benefit from its own collected data, it will need to wait for a long time to collect sufficient data to build accurate...

  7. Using neutral models to identify constraints on low-severity fire regimes.

    Science.gov (United States)

    Donald McKenzie; Amy E. Hessl; Lara-Karena B. Kellogg

    2006-01-01

    Climate, topography, fuel loadings, and human activities all affect spatial and temporal patterns of fire occurrence. Because fire is modeled as a stochastic process, for which each fire history is only one realization, a simulation approach is necessary to understand baseline variability, thereby identifying constraints, or forcing functions, that affect fire regimes...

  8. Validation of a probabilistic post-fire erosion model

    Science.gov (United States)

    Pete Robichaud; William J. Elliot; Sarah A. Lewis; Mary Ellen Miller

    2016-01-01

    Post-fire increases of runoff and erosion often occur and land managers need tools to be able to project the increased risk. The Erosion Risk Management Tool (ERMiT) uses the Water Erosion Prediction Project (WEPP) model as the underlying processor. ERMiT predicts the probability of a given amount of hillslope sediment delivery from a single rainfall or...

  9. Modeling the performance of coated LPG tanks engulfes in fires

    NARCIS (Netherlands)

    Cozzani, V.; Landucci, G.; Molag, M. (Menso)

    2009-01-01

    The improvement of passive fire protection of storage vessels is a key factor to enhance safety among the LPG distribution chain. A thermal and mechanical model based on finite elements simulations was developed to assess the behaviour of full size tanks used for LPG storage and transportation in

  10. Modeling of Ceiling Fire Spread and Thermal Radiation.

    Science.gov (United States)

    1981-10-01

    under a PMMA ceiling and flame lengths under an inert ceiling are found to be in reasonable agreement with full-scale behavior. Although fire spread...5 3 Flame Lengths under Full-Scale Ceilings 12 4 Correlation of Flame Length under Inert Ceilings 16 5 Correlation of Flame Length under No 234 Model...Ceilings 17 6 Correlation of Flame Length under No B8811 Model Ceilings 18 7 Correlation of Flame Length under No. 223 Model Ceilings 19 8

  11. Validating the Malheur model for predicting ponderosa pine post-fire mortality using 24 fires in the Pacific Northwest, USA

    Science.gov (United States)

    Walter G. Thies; Douglas J. Westlind

    2012-01-01

    Fires, whether intentionally or accidentally set, commonly occur in western interior forests of the US. Following fire, managers need the ability to predict mortality of individual trees based on easily observed characteristics. Previously, a two-factor model using crown scorch and bole scorch proportions was developed with data from 3415 trees for predicting the...

  12. Advancements in Hydrology and Erosion Process Understanding and Post-Fire Hydrologic and Erosion Model Development for Semi-Arid Landscapes

    Science.gov (United States)

    Williams, C. Jason; Pierson, Frederick B.; Al-Hamdan, Osama Z.; Robichaud, Peter R.; Nearing, Mark A.; Hernandez, Mariano; Weltz, Mark A.; Spaeth, Kenneth E.; Goodrich, David C.

    2017-04-01

    Fire activity continues to increase in semi-arid regions around the globe. Private and governmental land management entities are challenged with predicting and mitigating post-fire hydrologic and erosion responses on these landscapes. For more than a decade, a team of scientists with the US Department of Agriculture has collaborated on extensive post-fire hydrologic field research and the application of field research to development of post-fire hydrology and erosion predictive technologies. Experiments funded through this research investigated the impacts of fire on vegetation and soils and the effects of these fire-induced changes on infiltration, runoff generation, erodibility, and soil erosion processes. The distribution of study sites spans diverse topography across grassland, shrubland, and woodland landscapes throughout the western United States. Knowledge gleaned from the extensive field experiments was applied to develop and enhance physically-based models for hillslope- to watershed-scale runoff and erosion prediction. Our field research and subsequent data syntheses have identified key knowledge gaps and challenges regarding post-fire hydrology and erosion modeling. Our presentation details some consistent trends across a diverse domain and varying landscape conditions based on our extensive field campaigns. We demonstrate how field data have advanced our understanding of post-fire hydrology and erosion for semi-arid landscapes and highlight remaining key knowledge gaps. Lastly, we briefly show how our well-replicated experimental methodologies have contributed to advancements in hydrologic and erosion model development for the post-fire environment.

  13. MODEL OF COLLABORATIVE COURSES DEVELOPMENT IN DISTANCE LEARNING PLATFORMS

    Directory of Open Access Journals (Sweden)

    Dmytro S. Morozov

    2015-02-01

    Full Text Available The research paper outlines the problem of organization collaboration of users group on creation distance learning courses. The article contains analysis of the courses data structure. According to proposed structure the model of developer’s collaboration on creating distance learning courses based on basic principles of source code management was proposed. The article also provides result of research on necessary tools for collaborative development of courses in distance learning platforms. According to the requirements of flexibility and simplicity of access to system for any level educational institutions, technological decisions on granting permissions on performing basic operations on course elements and providing to user moderation’s privileges were proposed.

  14. Supporting FIRE-suppression strategies combining fire spread MODelling and SATellite data in an operational context in Portugal: the FIRE-MODSAT project

    Science.gov (United States)

    Sá, Ana C. L.; Benali, Akli; Pinto, Renata M. S.; Pereira, José M. C.; Trigo, Ricardo M.; DaCamara, Carlos C.

    2014-05-01

    Large wildfires are infrequent but account for the most severe environmental, ecological and socio-economic impacts. In recent years Portugal has suffered the impact of major heat waves that fuelled records of burnt area exceeding 400.000ha and 300.000ha in 2003 and 2005, respectively. According to the latest IPCC reports, the frequency and amplitude of summer heat waves over Iberia will very likely increase in the future. Therefore, most climate change studies point to an increase in the number and extent of wildfires. Thus, an increase in both wildfire impacts and fire suppression difficulties is expected. The spread of large wildfires results from a complex interaction between topography, meteorology and fuel properties. Wildfire spread models (e.g. FARSITE) are commonly used to simulate fire growth and behaviour and are an essential tool to understand their main drivers. Additionally, satellite active-fire data have been used to monitor the occurrence, extent, and spread of wildfires. Both satellite data and fire spread models provide different types of information about the spatial and temporal distribution of large wildfires and can potentially be used to support strategic decisions regarding fire suppression resource allocation. However, they have not been combined in a manner that fully exploits their potential and minimizes their limitations. A knowledge gap still exists in understanding how to minimize the impacts of large wildfires, leading to the following research question: What can we learn from past large wildfires in order to mitigate future fire impacts? FIRE-MODSAT is a one-year funded project by the Portuguese Foundation for the Science and Technology (FCT) that is founded on this research question, with the main goal of improving our understanding on the interactions between fire spread and its environmental drivers, to support fire management decisions in an operational context and generate valuable information to improve the efficiency of the

  15. Using an agent-based model to examine forest management outcomes in a fire-prone landscape in Oregon, USA

    Directory of Open Access Journals (Sweden)

    Thomas A. Spies

    2017-03-01

    with management, despite the occurrence of high-severity wildfire. Our results and further applications of the model could be used in collaborative settings to facilitate discussion and development of policies and practices for fire-prone landscapes.

  16. Laboratory modeling of aspects of large fires

    Science.gov (United States)

    Carrier, G. F.; Fendell, F. E.; Fleeter, R. D.; Gat, N.; Cohen, L. M.

    1984-04-01

    The design, construction, and use of a laboratory-scale combustion tunnel for simulating aspects of large-scale free-burning fires are described. The facility consists of an enclosed, rectangular-cross section (1.12 m wide x 1.27 m high) test section of about 5.6 m in length, fitted with large sidewall windows for viewing. A long upwind section permits smoothing (by screens and honeycombs) of a forced-convective flow, generated by a fan and adjustable in wind speed (up to a maximum speed of about 20 m/s prior to smoothing). Special provision is made for unconstrained ascent of a strongly buoyant plume, the duct over the test section being about 7 m in height. Also, a translatable test-section ceiling can be used to prevent jet-type spreading into the duct of the impressed flow; that is, the wind arriving at a site (say) half-way along the test section can be made (by ceiling movement) approximately the same as that at the leading edge of the test section with a fully open duct (fully retracted ceiling). Of particular interest here are the rate and structure of wind-aided flame spread streamwise along a uniform matrix of vertically oriented small fuel elements (such as toothpicks or coffee-strirrers), implanted in clay stratum on the test-section floor; this experiment is motivated by flame spread across strewn debris, such as may be anticipated in an urban environment after severe blast damage.

  17. Advancing Collaboration through Hydrologic Data and Model Sharing

    Science.gov (United States)

    Tarboton, D. G.; Idaszak, R.; Horsburgh, J. S.; Ames, D. P.; Goodall, J. L.; Band, L. E.; Merwade, V.; Couch, A.; Hooper, R. P.; Maidment, D. R.; Dash, P. K.; Stealey, M.; Yi, H.; Gan, T.; Castronova, A. M.; Miles, B.; Li, Z.; Morsy, M. M.

    2015-12-01

    HydroShare is an online, collaborative system for open sharing of hydrologic data, analytical tools, and models. It supports the sharing of and collaboration around "resources" which are defined primarily by standardized metadata, content data models for each resource type, and an overarching resource data model based on the Open Archives Initiative's Object Reuse and Exchange (OAI-ORE) standard and a hierarchical file packaging system called "BagIt". HydroShare expands the data sharing capability of the CUAHSI Hydrologic Information System by broadening the classes of data accommodated to include geospatial and multidimensional space-time datasets commonly used in hydrology. HydroShare also includes new capability for sharing models, model components, and analytical tools and will take advantage of emerging social media functionality to enhance information about and collaboration around hydrologic data and models. It also supports web services and server/cloud based computation operating on resources for the execution of hydrologic models and analysis and visualization of hydrologic data. HydroShare uses iRODS as a network file system for underlying storage of datasets and models. Collaboration is enabled by casting datasets and models as "social objects". Social functions include both private and public sharing, formation of collaborative groups of users, and value-added annotation of shared datasets and models. The HydroShare web interface and social media functions were developed using the Django web application framework coupled to iRODS. Data visualization and analysis is supported through the Tethys Platform web GIS software stack. Links to external systems are supported by RESTful web service interfaces to HydroShare's content. This presentation will introduce the HydroShare functionality developed to date and describe ongoing development of functionality to support collaboration and integration of data and models.

  18. Modelling and simulating fire tube boiler performance

    DEFF Research Database (Denmark)

    Sørensen, K.; Condra, T.; Houbak, Niels

    2003-01-01

    A model for a flue gas boiler covering the flue gas and the water-/steam side has been formulated. The model has been formulated as a number of sub models that are merged into an overall model for the complete boiler. Sub models have been defined for the furnace, the convection zone (split in 2......: a zone submerged in water and a zone covered by steam), a model for the material in the boiler (the steel) and 2 models for resp. the water/steam zone (the boiling) and the steam. The dynamic model has been developed as a number of Differential-Algebraic-Equation system (DAE). Subsequently Mat......Lab/Simulink has been applied for carrying out the simulations. To be able to verify the simulated results experiments has been carried out on a full scale boiler plant....

  19. BehavePlus fire modeling system, version 5.0: Variables

    Science.gov (United States)

    Patricia L. Andrews

    2009-01-01

    This publication has been revised to reflect updates to version 4.0 of the BehavePlus software. It was originally published as the BehavePlus fire modeling system, version 4.0: Variables in July, 2008.The BehavePlus fire modeling system is a computer program based on mathematical models that describe wildland fire behavior and effects and the...

  20. Post Fire Safe Shutdown Analysis Using a Fault Tree Logic Model

    International Nuclear Information System (INIS)

    Yim, Hyun Tae; Park, Jun Hyun

    2005-01-01

    Every nuclear power plant should have its own fire hazard analysis including the fire safe shutdown analysis. A safe shutdown (SSD) analysis is performed to demonstrate the capability of the plant to safely shut down for a fire in any given area. The basic assumption is that there will be fire damage to all cables and equipment located within a common fire area. When evaluating the SSD capabilities of the plant, based on a review of the systems, equipment and cables within each fire area, it should be determined which shutdown paths are either unaffected or least impacted by a postulated fire within the fire area. Instead of seeking a success path for safe shutdown given all cables and equipment damaged by a fire, there can be an alternative approach to determine the SSD capability: fault tree analysis. This paper introduces the methodology for fire SSD analysis using a fault tree logic model

  1. Modeling and Control of Collaborative Robot System using Haptic Feedback

    Directory of Open Access Journals (Sweden)

    Vivekananda Shanmuganatha

    2017-08-01

    Full Text Available When two robot systems can share understanding using any agreed knowledge, within the constraints of the system’s communication protocol, the approach may lead to a common improvement. This has persuaded numerous new research inquiries in human-robot collaboration. We have built up a framework prepared to do independent following and performing table-best protest object manipulation with humans and we have actualized two different activity models to trigger robot activities. The idea here is to explore collaborative systems and to build up a plan for them to work in a collaborative environment which has many benefits to a single more complex system. In the paper, two robots that cooperate among themselves are constructed. The participation linking the two robotic arms, the torque required and parameters are analyzed. Thus the purpose of this paper is to demonstrate a modular robot system which can serve as a base on aspects of robotics in collaborative robots using haptics.

  2. A Collaboration Service Model for a Global Port Cluster

    Directory of Open Access Journals (Sweden)

    Keith K.T. Toh

    2010-03-01

    Full Text Available The importance of port clusters to a global city may be viewed from a number of perspectives. The development of port clusters and economies of agglomeration and their contribution to a regional economy is underpinned by information and physical infrastructure that facilitates collaboration between business entities within the cluster. The maturity of technologies providing portals, web and middleware services provides an opportunity to push the boundaries of contemporary service reference models and service catalogues to what the authors propose to be "collaboration services". Servicing port clusters, portal engineers of the future must consider collaboration services to benefit a region. Particularly, service orchestration through a "public user portal" must gain better utilisation of publically owned infrastructure, to share knowledge and collaborate among organisations through information systems.

  3. Integrating Collaborative and Decentralized Models to Support Ubiquitous Learning

    Science.gov (United States)

    Barbosa, Jorge Luis Victória; Barbosa, Débora Nice Ferrari; Rigo, Sandro José; de Oliveira, Jezer Machado; Rabello, Solon Andrade, Jr.

    2014-01-01

    The application of ubiquitous technologies in the improvement of education strategies is called Ubiquitous Learning. This article proposes the integration between two models dedicated to support ubiquitous learning environments, called Global and CoolEdu. CoolEdu is a generic collaboration model for decentralized environments. Global is an…

  4. Geometric Models for Collaborative Search and Filtering

    Science.gov (United States)

    Bitton, Ephrat

    2011-01-01

    This dissertation explores the use of geometric and graphical models for a variety of information search and filtering applications. These models serve to provide an intuitive understanding of the problem domains and as well as computational efficiencies to our solution approaches. We begin by considering a search and rescue scenario where both…

  5. EARTH, WIND AND FIRE: BUILDING METEOROLOGICALLY-SENSITIVE BIOGENIC AND WILDLAND FIRE EMISSION ESTIMATES FOR AIR QUALITY MODELS

    Science.gov (United States)

    Emission estimates are important for ensuring the accuracy of atmospheric chemical transport models. Estimates of biogenic and wildland fire emissions, because of their sensitivity to meteorological conditions, need to be carefully constructed and closely linked with a meteorolo...

  6. The Morris-Lecar neuron model embeds a leaky integrate-and-fire model

    DEFF Research Database (Denmark)

    Ditlevsen, Susanne; Greenwood, Priscilla

    2013-01-01

    We showthat the stochastic Morris–Lecar neuron, in a neighborhood of its stable point, can be approximated by a two-dimensional Ornstein Uhlenbeck (OU) modulation of a constant circular motion. The associated radial OU process is an example of a leaky integrate-and-fire (LIF) model prior to firing...

  7. Foundations for a multiscale collaborative Earth model

    KAUST Repository

    Afanasiev, M.; Peter, Daniel; Sager, K.; Simut, S.; Ermert, L.; Krischer, L.; Fichtner, A.

    2015-01-01

    . The CSEM as a computational framework is intended to help bridging the gap between local, regional and global tomography, and to contribute to the development of a global multiscale Earth model. While the current construction serves as a first proof

  8. Tag-Driven Online Novel Recommendation with Collaborative Item Modeling

    Directory of Open Access Journals (Sweden)

    Fenghuan Li

    2018-04-01

    Full Text Available Online novel recommendation recommends attractive novels according to the preferences and characteristics of users or novels and is increasingly touted as an indispensable service of many online stores and websites. The interests of the majority of users remain stable over a certain period. However, there are broad categories in the initial recommendation list achieved by collaborative filtering (CF. That is to say, it is very possible that there are many inappropriately recommended novels. Meanwhile, most algorithms assume that users can provide an explicit preference. However, this assumption does not always hold, especially in online novel reading. To solve these issues, a tag-driven algorithm with collaborative item modeling (TDCIM is proposed for online novel recommendation. Online novel reading is different from traditional book marketing and lacks preference rating. In addition, collaborative filtering frequently suffers from the Matthew effect, leading to ignored personalized recommendations and serious long tail problems. Therefore, item-based CF is improved by latent preference rating with a punishment mechanism based on novel popularity. Consequently, a tag-driven algorithm is constructed by means of collaborative item modeling and tag extension. Experimental results show that online novel recommendation is improved greatly by a tag-driven algorithm with collaborative item modeling.

  9. Interprofessional Collaborative Practice Models in Chronic Disease Management.

    Science.gov (United States)

    Southerland, Janet H; Webster-Cyriaque, Jennifer; Bednarsh, Helene; Mouton, Charles P

    2016-10-01

    Interprofessional collaboration in health has become essential to providing high-quality care, decreased costs, and improved outcomes. Patient-centered care requires synthesis of all the components of primary and specialty medicine to address patient needs. For individuals living with chronic diseases, this model is even more critical to obtain better health outcomes. Studies have shown shown that oral health and systemic disease are correlated as it relates to disease development and progression. Thus, inclusion of oral health in many of the existing and new collaborative models could result in better management of chronic illnesses and improve overall health outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Collaborative business modeling for systemic and sustainability innovations

    DEFF Research Database (Denmark)

    Rohrbeck, René; Konnertz, L.; Knab, S.

    2013-01-01

    Sustainability innovations are characterized by a systemic nature, and require that multiple organizations act in an orchestrated fashion. To jointly identify opportunities and plan sustainability innovations, new methods and approaches are needed. In this article we describe a case study where 8...... firms have collaborated to envision and create new business models in the energy industry. After describing this collaborative business modelling (CBM) approach, we discuss its strengths and limitations and compare it to two alternative methods of strategy and innovation planning: scenario technique...

  11. First Order Fire Effects Model: FOFEM 4.0, user's guide

    Science.gov (United States)

    Elizabeth D. Reinhardt; Robert E. Keane; James K. Brown

    1997-01-01

    A First Order Fire Effects Model (FOFEM) was developed to predict the direct consequences of prescribed fire and wildfire. FOFEM computes duff and woody fuel consumption, smoke production, and fire-caused tree mortality for most forest and rangeland types in the United States. The model is available as a computer program for PC or Data General computer.

  12. Numerical Modelling of Fire-Atmosphere Interactions and the 2003 Canberra Bushfires

    Science.gov (United States)

    Simpson, C.; Sturman, A.; Zawar-Reza, P.

    2010-12-01

    It is well known that the behaviour of a wildland fire is strongly associated with the conditions of its surrounding atmosphere. However, the two-way interactions between fire behaviour and the atmospheric conditions are not well understood. A numerical model is used to simulate wildland fires so that the nature of these fire-atmosphere interactions, and how they might affect fire behaviour, can be further investigated. The 2003 Canberra bushfires are used as a case study due to their highly destructive and unusual behaviour. On the 18th January 2003, these fires spread to the urban suburbs of Canberra, resulting in the loss of four lives and the destruction of over 500 homes. Fire-atmosphere interactions are believed to have played an important role in making these fires so destructive. WRF-Fire is used to perform real data simulations of the 2003 Canberra bushfires. WRF-Fire is a coupled fire-atmosphere model, which combines a semi-empirical fire spread model with an atmospheric model, allowing it to directly simulate the two-way interactions between a fire and its surrounding atmosphere. These simulations show the impact of the presence of a fire on conditions within the atmospheric boundary layer. This modification of the atmosphere, resulting from the injection of heat and moisture released by the fire, appears to have a direct feedback onto the overall fire behaviour. The bushfire simulations presented in this paper provide important scientific insights into the nature of fire-atmosphere interactions for a real situation. It is expected that they will also help fire managers in Australia to better understand why the 2003 Canberra bushfires were so destructive, as well as to gain improved insight into bushfire behaviour in general.

  13. An Alignment Model for Collaborative Value Networks

    Science.gov (United States)

    Bremer, Carlos; Azevedo, Rodrigo Cambiaghi; Klen, Alexandra Pereira

    This paper presents parts of the work carried out in several global organizations through the development of strategic projects with high tactical and operational complexity. By investing in long-term relationships, strongly operating in the transformation of the competitive model and focusing on the value chain management, the main aim of these projects was the alignment of multiple value chains. The projects were led by the Axia Transformation Methodology as well as by its Management Model and following the principles of Project Management. As a concrete result of the efforts made in the last years in the Brazilian market this work also introduces the Alignment Model which supports the transformation process that the companies undergo.

  14. Theory of the one-dimensional forest-fire model

    International Nuclear Information System (INIS)

    Paczuski, M.; Bak, P.

    1993-01-01

    Turbulent cascade processes are studied in terms of a one-dimensional forest-fire model. A hier- archy of steady-state equations for the forests and the holes between them is constructed and solved within a mean-field closure scheme. The exact hole distribution function is found to be N H (s)=4N/[s(s+1)(s+2)], where N is the number of forests

  15. Fires involving radioactive materials : transference model; operative recommendations

    International Nuclear Information System (INIS)

    Rodriguez, C.E.; Puntarulo, L.J.; Canibano, J.A.

    1988-01-01

    In all aspects related to the nuclear activity, the occurrence of an explosion, fire or burst type accident, with or without victims, is directly related to the characteristics of the site. The present work analyses the different parameters involved, describing a transference model and recommendations for evaluation and control of the radiological risk for firemen. Special emphasis is placed on the measurement of the variables existing in this kind of operations

  16. Implementation strategies for collaborative primary care-mental health models.

    Science.gov (United States)

    Franx, Gerdien; Dixon, Lisa; Wensing, Michel; Pincus, Harold

    2013-09-01

    Extensive research exists that collaborative primary care-mental health models can improve care and outcomes for patients. These programs are currently being implemented throughout the United States and beyond. The purpose of this study is to review the literature and to generate an overview of strategies currently used to implement such models in daily practice. Six overlapping strategies to implement collaborative primary care-mental health models were described in 18 selected studies. We identified interactive educational strategies, quality improvement change processes, technological support tools, stakeholder engagement in the design and execution of implementation plans, organizational changes in terms of expanding the task of nurses and financial strategies such as additional collaboration fees and pay for performance incentives. Considering the overwhelming evidence about the effectiveness of primary care-mental health models, there is a lack of good studies focusing on their implementation strategies. In practice, these strategies are multifaceted and locally defined, as a result of intensive and required stakeholder engagement. Although many barriers still exist, the implementation of collaborative models could have a chance to succeed in the United States, where new service delivery and payment models, such as the Patient-Centered Medical Home, the Health Home and the Accountable Care Organization, are being promoted.

  17. Understanding global fire dynamics by classifying and comparing spatial models of vegetation and fire

    Science.gov (United States)

    Robert E. Keane; Geoffrey J. Cary; Ian D. Davies; Michael D. Flannigan; Robert H. Gardner; Sandra Lavorel; James M. Lenihan; Chao Li; T. Scott Rupp

    2007-01-01

    Wildland fire is a major disturbance in most ecosystems worldwide (Crutzen and Goldammer 1993). The interaction of fire with climate and vegetation over long time spans, often referred to as the fire regime (Agee 1993; Clark 1993; Swetnam and Baisan 1996; Swetnam 1997), has major effects on dominant vegetation, ecosystem carbon budget, and biodiversity (Gardner et aL...

  18. Modeling impacts of fire severity on successional trajectories and future fire behavior in Alaskan boreal forests

    Science.gov (United States)

    Jill F. Johnstone; T. Scott Rupp; Mark Olson; David. Verbyla

    2011-01-01

    Much of the boreal forest in western North America and Alaska experiences frequent, stand-replacing wildfires. Secondary succession after fire initiates most forest stands and variations in fire characteristics can have strong effects on pathways of succession. Variations in surface fire severity that influence whether regenerating forests are dominated by coniferous...

  19. Cooperative Teaching: A Model for Teacher Collaboration.

    Science.gov (United States)

    Bohlmann, Natalie L.

    1998-01-01

    A third grade teacher examines the effects of cooperative teaching in a two-teacher classroom. After discussing teacher roles in such classrooms, the paper describes how the advantages of such a system greatly outweigh the disadvantages. The paper presents keys to a successful teaching partnership and describes several models for lesson…

  20. Modelling post-fire vegetation recovery in Portugal

    Directory of Open Access Journals (Sweden)

    A. Bastos

    2011-12-01

    Full Text Available Wildfires in Mediterranean Europe have been increasing in number and extension over the last decades and constitute one of the major disturbances of these ecosystems. Portugal is the country with more burnt area in the last decade and the years of 2003 and 2005 were particularly devastating, the total burned areas of 425 000 and 338 000 ha being several times higher than the corresponding average. The year of 2005 further coincided with one of the most severe droughts since early 20th century. Due to different responses of vegetation to diverse fire regimes and to the complexity of landscape structures, fires have complex effects on vegetation recovery. Remote sensing has revealed to be a powerful tool in studying vegetation dynamics and in monitoring post-fire vegetation recovery, which is crucial to land-management and to prevent erosion.

    The main goals of the present work are (i to assess the accuracy of a vegetation recovery model previously developed by the authors; (ii to assess the model's performance, namely its sensitivity to initial conditions, to the temporal length of the input dataset and to missing data; (iii to study vegetation recovery over two selected areas that were affected by two large wildfire events in the fire seasons of 2003 and 2005, respectively.

    The study relies on monthly values of NDVI over 11 years (1998–2009, at 1 km × 1 km spatial resolution, as obtained by the VEGETATION instrument. According to results from sensitivity analysis, the model is robust and able to provide good estimations of recovery times of vegetation when the regeneration process is regular, even when missing data is present. In respect to the two selected burnt scars, results indicate that fire damage is a determinant factor of regeneration, as less damaged vegetation recovers more rapidly, which is mainly justified by the high coverage of Pinus pinaster over the area, and by the fact that coniferous forests tend to

  1. Modelling post-fire vegetation recovery in Portugal

    Science.gov (United States)

    Bastos, A.; Gouveia, C. M.; Dacamara, C. C.; Trigo, R. M.

    2011-12-01

    Wildfires in Mediterranean Europe have been increasing in number and extension over the last decades and constitute one of the major disturbances of these ecosystems. Portugal is the country with more burnt area in the last decade and the years of 2003 and 2005 were particularly devastating, the total burned areas of 425 000 and 338 000 ha being several times higher than the corresponding average. The year of 2005 further coincided with one of the most severe droughts since early 20th century. Due to different responses of vegetation to diverse fire regimes and to the complexity of landscape structures, fires have complex effects on vegetation recovery. Remote sensing has revealed to be a powerful tool in studying vegetation dynamics and in monitoring post-fire vegetation recovery, which is crucial to land-management and to prevent erosion. The main goals of the present work are (i) to assess the accuracy of a vegetation recovery model previously developed by the authors; (ii) to assess the model's performance, namely its sensitivity to initial conditions, to the temporal length of the input dataset and to missing data; (iii) to study vegetation recovery over two selected areas that were affected by two large wildfire events in the fire seasons of 2003 and 2005, respectively. The study relies on monthly values of NDVI over 11 years (1998-2009), at 1 km × 1 km spatial resolution, as obtained by the VEGETATION instrument. According to results from sensitivity analysis, the model is robust and able to provide good estimations of recovery times of vegetation when the regeneration process is regular, even when missing data is present. In respect to the two selected burnt scars, results indicate that fire damage is a determinant factor of regeneration, as less damaged vegetation recovers more rapidly, which is mainly justified by the high coverage of Pinus pinaster over the area, and by the fact that coniferous forests tend to recover slower than transitional woodland

  2. Analytic expressions for the construction of a fire event PSA model

    International Nuclear Information System (INIS)

    Kang, Dae Il; Kim, Kil Yoo; Kim, Dong San; Hwang, Mee Jeong; Yang, Joon Eon

    2016-01-01

    In this study, the changing process of an internal event PSA model to a fire event PSA model is analytically presented and discussed. Many fire PSA models have fire induced initiating event fault trees not shown in an internal event PSA model. Fire-induced initiating fault tree models are developed for addressing multiple initiating event issues. A single fire event within a fire compartment or fire scenario can cause multiple initiating events. As an example, a fire in a turbine building area can cause a loss of the main feed-water and loss of off-site power initiating events. Up to now, there has been no analytic study on the construction of a fire event PSA model using an internal event PSA model with fault trees of initiating events. In this paper, the changing process of an internal event PSA model to a fire event PSA model was analytically presented and discussed. This study results show that additional cutsets can be obtained if the fault trees of initiating events for a fire event PSA model are not exactly developed.

  3. Analytic expressions for the construction of a fire event PSA model

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Dae Il; Kim, Kil Yoo; Kim, Dong San; Hwang, Mee Jeong; Yang, Joon Eon [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    In this study, the changing process of an internal event PSA model to a fire event PSA model is analytically presented and discussed. Many fire PSA models have fire induced initiating event fault trees not shown in an internal event PSA model. Fire-induced initiating fault tree models are developed for addressing multiple initiating event issues. A single fire event within a fire compartment or fire scenario can cause multiple initiating events. As an example, a fire in a turbine building area can cause a loss of the main feed-water and loss of off-site power initiating events. Up to now, there has been no analytic study on the construction of a fire event PSA model using an internal event PSA model with fault trees of initiating events. In this paper, the changing process of an internal event PSA model to a fire event PSA model was analytically presented and discussed. This study results show that additional cutsets can be obtained if the fault trees of initiating events for a fire event PSA model are not exactly developed.

  4. Identification of fire modeling issues based on an analysis of real events from the OECD FIRE database

    Energy Technology Data Exchange (ETDEWEB)

    Hermann, Dominik [Swiss Federal Nuclear Safety Inspectorate ENSI, Brugg (Switzerland)

    2017-03-15

    Precursor analysis is widely used in the nuclear industry to judge the significance of events relevant to safety. However, in case of events that may damage equipment through effects that are not ordinary functional dependencies, the analysis may not always fully appreciate the potential for further evolution of the event. For fires, which are one class of such events, this paper discusses modelling challenges that need to be overcome when performing a probabilistic precursor analysis. The events used to analyze are selected from the Organisation for Economic Cooperation and Development (OECD) Fire Incidents Records Exchange (FIRE) Database.

  5. Modeling the performance of coated LPG tanks engulfed in fires

    Energy Technology Data Exchange (ETDEWEB)

    Landucci, Gabriele [CONPRICI - Dipartimento di Ingegneria Chimica, Chimica Industriale e Scienza dei Materiali, Universita di Pisa, via Diotisalvi n.2, 56126 Pisa (Italy); Molag, Menso [Nederlandse Organisatie voor toegepast-natuurwetenschappelijk onderzoek TNO, Princetonlaan 6, 3584 CB Utrecht (Netherlands); Cozzani, Valerio, E-mail: valerio.cozzani@unibo.it [CONPRICI - Dipartimento di Ingegneria Chimica, Mineraria e delle Tecnologie Ambientali, Alma Mater Studiorum - Universita di Bologna, Via Terracini 28 - 40131 Bologna (Italy)

    2009-12-15

    The improvement of passive fire protection of storage vessels is a key factor to enhance safety among the LPG distribution chain. A thermal and mechanical model based on finite elements simulations was developed to assess the behaviour of full size tanks used for LPG storage and transportation in fire engulfment scenarios. The model was validated by experimental results. A specific analysis of the performance of four different reference coating materials was then carried out, also defining specific key performance indicators (KPIs) to assess design safety margins in near-miss simulations. The results confirmed the wide influence of coating application on the expected vessel time to failure due to fire engulfment. A quite different performance of the alternative coating materials was evidenced. General correlations were developed among the vessel time to failure and the effective coating thickness in full engulfment scenarios, providing a preliminary assessment of the coating thickness required to prevent tank rupture for a given time lapse. The KPIs defined allowed the assessment of the available safety margins in the reference scenarios analyzed and of the robustness of thermal protection design.

  6. Modeling the performance of coated LPG tanks engulfed in fires

    International Nuclear Information System (INIS)

    Landucci, Gabriele; Molag, Menso; Cozzani, Valerio

    2009-01-01

    The improvement of passive fire protection of storage vessels is a key factor to enhance safety among the LPG distribution chain. A thermal and mechanical model based on finite elements simulations was developed to assess the behaviour of full size tanks used for LPG storage and transportation in fire engulfment scenarios. The model was validated by experimental results. A specific analysis of the performance of four different reference coating materials was then carried out, also defining specific key performance indicators (KPIs) to assess design safety margins in near-miss simulations. The results confirmed the wide influence of coating application on the expected vessel time to failure due to fire engulfment. A quite different performance of the alternative coating materials was evidenced. General correlations were developed among the vessel time to failure and the effective coating thickness in full engulfment scenarios, providing a preliminary assessment of the coating thickness required to prevent tank rupture for a given time lapse. The KPIs defined allowed the assessment of the available safety margins in the reference scenarios analyzed and of the robustness of thermal protection design.

  7. Modelling Global Pattern Formations for Collaborative Learning Environments

    DEFF Research Database (Denmark)

    Grappiolo, Corrado; Cheong, Yun-Gyung; Khaled, Rilla

    2012-01-01

    We present our research towards the design of a computational framework capable of modelling the formation and evolution of global patterns (i.e. group structures) in a population of social individuals. The framework is intended to be used in collaborative environments, e.g. social serious games...

  8. Collaborative business model development for home energy renovations

    NARCIS (Netherlands)

    Mlecnik, E.; Straub, A.; Haavik, T

    2018-01-01

    In the EU, housing retrofit rates have to increase to about 2.5–3% of the housing stock per year to achieve policy goals. The development of new business models and collaboration of SMEs in a fragmented market is expected to result in an increase in home renovations. This study presents a way to

  9. A collaborative project on the effects of coal quality on NO{sub x} emissions and carbon burnout in pulverised coal-fired utility boilers

    Energy Technology Data Exchange (ETDEWEB)

    Tilley, H.A.; O`Connor, M.; Stephenson, P.L.; Whitehouse, M.; Richards, D.G.; Hesselmann, G.; MacPhail, J.; Lockwood, F.C.; Williamson, J.; Williams, A.; Pourkashanian, M. [ETSU, Harwell (United Kingdom)

    1998-12-01

    This paper describes a UK Department of Trade and Industry-supported collaborative project entitled `The Effects of Coal Quality on Emission of Oxides of Nitrogen (NO{sub x}) and Carbon Burnout in Pulverised Coal-fired Utility Boilers`. The project involved extensive collaboration between the UK power generators, boiler and burner manufacturers and research groups in both industry and academia, together with several of the world`s leading computational fluid dynamics (CFD) `software houses`. The prime objectives of the project were to assess the relationship between NO{sub x} emissions and carbon burnout and to develop and validate predictive tools for assessing coals. Experimental work was carried out on various laboratory-scale apparatus and on single burner test facilities ranging from 160 kW{sub th} to 40 MW{sub th} in size and measurements were obtained from full-scale 500 MW{sub e} utility boiler trials. This data and basic coal data were then used to develop mathematical models to predict full-scale boiler performance with respect to NO{sub x} emissions and carbon-in-ash. Results showed good correlations for NO{sub x} and carbon burnout when comparing data from full-scale and large-scale rig trials. Laboratory-scale tests were found to be useful but the influence of burner aerodynamics was more difficult to quantify. Modelling showed that predicted NO{sub x} emissions were encouragingly close to measured emissions but predicting carbon burnout was less successful. 24 refs., 4 figs., 6 tabs.

  10. Incorporating anthropogenic influences into fire probability models: Effects of development and climate change on fire activity in California

    Science.gov (United States)

    Mann, M.; Moritz, M.; Batllori, E.; Waller, E.; Krawchuk, M.; Berck, P.

    2014-12-01

    The costly interactions between humans and natural fire regimes throughout California demonstrate the need to understand the uncertainties surrounding wildfire, especially in the face of a changing climate and expanding human communities. Although a number of statistical and process-based wildfire models exist for California, there is enormous uncertainty about the location and number of future fires. Models estimate an increase in fire occurrence between nine and fifty-three percent by the end of the century. Our goal is to assess the role of uncertainty in climate and anthropogenic influences on the state's fire regime from 2000-2050. We develop an empirical model that integrates novel information about the distribution and characteristics of future plant communities without assuming a particular distribution, and improve on previous efforts by integrating dynamic estimates of population density at each forecast time step. Historically, we find that anthropogenic influences account for up to fifty percent of the total fire count, and that further housing development will incite or suppress additional fires according to their intensity. We also find that the total area burned is likely to increase but at a slower than historical rate. Previous findings of substantially increased numbers of fires may be tied to the assumption of static fuel loadings, and the use of proxy variables not relevant to plant community distributions. We also find considerable agreement between GFDL and PCM model A2 runs, with decreasing fire counts expected only in areas of coastal influence below San Francisco and above Los Angeles. Due to potential shifts in rainfall patterns, substantial uncertainty remains for the semiarid deserts of the inland south. The broad shifts of wildfire between California's climatic regions forecast in this study point to dramatic shifts in the pressures plant and human communities will face by midcentury. The information provided by this study reduces the

  11. A Coterminous Collaborative Learning Model: Interconnectivity of Leadership and Learning

    Directory of Open Access Journals (Sweden)

    Ilana Margolin

    2012-05-01

    Full Text Available This qualitative ethnographic study examines a collaborative leadership model focused on learning and socially just practices within a change context of a wide educational partnership. The study analyzes a range of perspectives of novice teachers, mentor teachers, teacher educators and district superintendents on leadership and learning. The findings reveal the emergence of a coalition of leaders crossing borders at all levels of the educational system: local school level, district level and teacher education level who were involved in coterminous collaborative learning. Four categories of learning were identified as critical to leading a change in the educational system: learning in professional communities, learning from practice, learning through theory and research and learning from and with leaders. The implications of the study for policy makers as well as for practitioners are to adopt a holistic approach to the educational environment and plan a collaborative learning continuum from initial pre-service programs through professional development learning at all levels.

  12. Communicate and collaborate by using building information modeling

    DEFF Research Database (Denmark)

    Mondrup, Thomas Fænø; Karlshøj, Jan; Vestergaard, Flemming

    Building Information Modeling (BIM) represents a new approach within the Architecture, Engineering, and Construction (AEC) industry, one that encourages collaboration and engagement of all stakeholders on a project. This study discusses the potential of adopting BIM as a communication...... and collaboration platform. The discussion is based on: (1) a review of the latest BIM literature, (2) a qualitative survey of professionals within the industry, and (3) mapping of available BIM standards. This study presents the potential benefits, risks, and the overarching challenges of adopting BIM, and makes...... recommendations for its use, particularly as a tool for collaboration. Specifically, this study focuses on the issue of implementing standardized BIM guidelines across national borders (in this study Denmark and Sweden), and discusses the challenge of developing a common standard applicable and acceptable at both...

  13. A Model for Collaborative Learning in Undergraduate Climate Change Courses

    Science.gov (United States)

    Teranes, J. L.

    2008-12-01

    Like several colleges and universities across the nation, the University of California, San Diego, has introduced climate change topics into many existing and new undergraduate courses. I have administered a program in this area at UCSD and have also developed and taught a new lower-division UCSD course entitled "Climate Change and Society", a general education course for non-majors. This class covers the basics of climate change, such as the science that explains it, the causes of climate change, climate change impacts, and mitigation strategies. The teaching methods for this course stress interdisciplinary approaches. I find that inquiry-based and collaborative modes of learning are particularly effective when applied to science-based climate, environmental and sustainability topics. Undergraduate education is often dominated by a competitive and individualistic approach to learning. In this approach, individual success is frequently perceived as contingent on others being less successful. Such a model is at odds with commonly stated goals of teaching climate change and sustainability, which are to equip students to contribute to the debate on global environmental change and societal adaptation strategies; and to help students become better informed citizens and decision makers. I present classroom-tested strategies for developing collaborative forms of learning in climate change and environmental courses, including team projects, group presentations and group assessment exercises. I show how critical thinking skills and long-term retention of information can benefit in the collaborative mode of learning. I find that a collaborative learning model is especially appropriate to general education courses in which the enrolled student body represents a wide diversity of majors, class level and expertise. I also connect collaborative coursework in interdisciplinary environmental topics directly to applications in the field, where so much "real-world" achievement in

  14. Research on mixed network architecture collaborative application model

    Science.gov (United States)

    Jing, Changfeng; Zhao, Xi'an; Liang, Song

    2009-10-01

    When facing complex requirements of city development, ever-growing spatial data, rapid development of geographical business and increasing business complexity, collaboration between multiple users and departments is needed urgently, however conventional GIS software (such as Client/Server model or Browser/Server model) are not support this well. Collaborative application is one of the good resolutions. Collaborative application has four main problems to resolve: consistency and co-edit conflict, real-time responsiveness, unconstrained operation, spatial data recoverability. In paper, application model called AMCM is put forward based on agent and multi-level cache. AMCM can be used in mixed network structure and supports distributed collaborative. Agent is an autonomous, interactive, initiative and reactive computing entity in a distributed environment. Agent has been used in many fields such as compute science and automation. Agent brings new methods for cooperation and the access for spatial data. Multi-level cache is a part of full data. It reduces the network load and improves the access and handle of spatial data, especially, in editing the spatial data. With agent technology, we make full use of its characteristics of intelligent for managing the cache and cooperative editing that brings a new method for distributed cooperation and improves the efficiency.

  15. A dialogue game for analysing group model building: framing collaborative modelling and its facilitation

    NARCIS (Netherlands)

    Hoppenbrouwers, S.J.B.A.; Rouwette, E.A.J.A.

    2012-01-01

    This paper concerns a specific approach to analysing and structuring operational situations in collaborative modelling. Collaborative modelling is viewed here as 'the goal-driven creation and shaping of models that are based on the principles of rational description and reasoning'. Our long term

  16. Modeling very large-fire occurrences over the continental United States from weather and climate forcing

    Science.gov (United States)

    R Barbero; J T Abatzoglou; E A Steel

    2014-01-01

    Very large-fires (VLFs) have widespread impacts on ecosystems, air quality, fire suppression resources, and in many regions account for a majority of total area burned. Empirical generalized linear models of the largest fires (>5000 ha) across the contiguous United States (US) were developed at ¡­60 km spatial and weekly temporal resolutions using solely atmospheric...

  17. Challenges of assessing fire and burn severity using field measures, remote sensing and modelling

    Science.gov (United States)

    Penelope Morgan; Robert E. Keane; Gregory K. Dillon; Theresa B. Jain; Andrew T. Hudak; Eva C. Karau; Pamela G. Sikkink; Zachery A. Holden; Eva K. Strand

    2014-01-01

    Comprehensive assessment of ecological change after fires have burned forests and rangelands is important if we are to understand, predict and measure fire effects. We highlight the challenges in effective assessment of fire and burn severity in the field and using both remote sensing and simulation models. We draw on diverse recent research for guidance on assessing...

  18. Assessing accuracy of point fire intervals across landscapes with simulation modelling

    Science.gov (United States)

    Russell A. Parsons; Emily K. Heyerdahl; Robert E. Keane; Brigitte Dorner; Joseph Fall

    2007-01-01

    We assessed accuracy in point fire intervals using a simulation model that sampled four spatially explicit simulated fire histories. These histories varied in fire frequency and size and were simulated on a flat landscape with two forest types (dry versus mesic). We used three sampling designs (random, systematic grids, and stratified). We assessed the sensitivity of...

  19. Developments in modelling of thermal radiation from pool and jet fires

    NARCIS (Netherlands)

    Boot, H.

    2016-01-01

    In the past decades, the standard approach in the modelling of consequences of pool and jet fires would be to describe these fires as tilted cylindrical shaped radiating flame surfaces, having a specific SEP (Surface Emissive Power). Some fine tuning on pool fires has been done by Rew and Hulbert in

  20. Modelling of Fire in an Open Car Park

    DEFF Research Database (Denmark)

    Marton, Timea; Dederichs, Anne Simone; Giuliani, Luisa

    2015-01-01

    Steel car parks exhibit high vulnerability to fire, as a consequence of the degradation of the steel mechanical properties at high temperatures and of the combustible type and amount. Real fire accidents in open car parks demonstrated a much faster and extended fire spread than predictions......, assuming that a fire spread rate of 12 min and consider at most 3-4 vehicles on fire at the same time. Fire Dynamic Simulator (FDS) is applied in this current paper to study fire spread between cars. The outcomes of the investigations show that the fire spread is strongly influenced by the geometrical...... layout and that the distance between cars plays a determinant role on the fire spread rate and ignition of adjacent cars. In particular it was found that the fire spread can be faster than 12 minutes in the case of the cars parked 40 and 60 cm from each other....

  1. Axion and PVLAS Collaboration data in a little Higgs model

    International Nuclear Information System (INIS)

    Fukuyama, Takeshi; Kikuchi, Tatsuru

    2006-01-01

    Little Higgs models may provide a solution to the gauge hierarchy problem in the mass of the Higgs boson. In this framework the Higgs boson arises as the pseudo-Nambu-Goldstone (PNG) boson. We show that the lepton triplet introduced in a little Higgs model explains a small mass parameter in the double see-saw mechanism for neutrino masses, and it can also gives an explanation for the axionlike particle recently reported by PVLAS collaboration

  2. Assessing the value of increased model resolution in forecasting fire danger

    Science.gov (United States)

    Jeanne Hoadley; Miriam Rorig; Ken Westrick; Larry Bradshaw; Sue Ferguson; Scott Goodrick; Paul Werth

    2003-01-01

    The fire season of 2000 was used as a case study to assess the value of increasing mesoscale model resolution for fire weather and fire danger forecasting. With a domain centered on Western Montana and Northern Idaho, MM5 simulations were run at 36, 12, and 4-km resolutions for a 30 day period at the height of the fire season. Verification analyses for meteorological...

  3. Numerical Field Model Simulation of Full Scale Fire Tests in a Closed Spherical/Cylindrical Vessel.

    Science.gov (United States)

    1987-12-01

    the behavior of an actual fire on board a ship. The computer model will be verified by the experimental data obtained in Fire-l. It is important to... behavior in simulations where convection is important. The upwind differencing scheme takes into account the unsymmetrical phenomenon of convection by using...TANK CELL ON THE NORTH SIDE) FOR A * * PARTICULAR FIRE CELL * * COSUMS (I,J) = THE ARRAY TO STORE THE SIMILIAR VALUE FOR THE FIRE * * CELL TO THE SOUTH

  4. Elements of a collaborative systems model within the aerospace industry

    Science.gov (United States)

    Westphalen, Bailee R.

    2000-10-01

    Scope and method of study. The purpose of this study was to determine the components of current aerospace collaborative efforts. There were 44 participants from two selected groups surveyed for this study. Nineteen were from the Oklahoma Air National Guard based in Oklahoma City representing the aviation group. Twenty-five participants were from the NASA Johnson Space Center in Houston representing the aerospace group. The surveys for the aviation group were completed in reference to planning missions necessary to their operations. The surveys for the aerospace group were completed in reference to a well-defined and focused goal from a current mission. A questionnaire was developed to survey active participants of collaborative systems in order to consider various components found within the literature. Results were analyzed and aggregated through a database along with content analysis of open-ended question comments from respondents. Findings and conclusions. This study found and determined elements of a collaborative systems model in the aerospace industry. The elements were (1) purpose or mission for the group or team; (2) commitment or dedication to the challenge; (3) group or team meetings and discussions; (4) constraints of deadlines and budgets; (5) tools and resources for project and simulations; (6) significant contributors to the collaboration; (7) decision-making formats; (8) reviews of project; (9) participants education and employment longevity; (10) cross functionality of team or group members; (11) training on the job plus teambuilding; (12) other key elements identified relevant by the respondents but not included in the model such as communication and teamwork; (13) individual and group accountability; (14) conflict, learning, and performance; along with (15) intraorganizational coordination. These elements supported and allowed multiple individuals working together to solve a common problem or to develop innovation that could not have been

  5. Analysis Evacuation Route for KM Zahro Express on Fire Condition using Agent Based Modeling and Fire Dynamics Simulatior

    Directory of Open Access Journals (Sweden)

    Trika Pitana

    2017-09-01

    Full Text Available Safety is the thing that needs to be preferred by users of transport, passengers should also understand about safety procedures and evacuation procedures in the means of transport. There have been many accidents that happen in the world of transport, particularly in the shipping world, from 2010 to 2016 is no more than 50 accidents of ships in accordance with the cause recorded by KNKT (Komisi Nasional Keselamatan Transportasi. On this research was discussed the evacuation time on the ship KM Zahro express that occurred earlier in the year 2017 in the Kepulauan Seribu, DKI Jakarta. Almost all passenger dead caused by fire from power source in engine room. This thesis will explaine about evacuation time and dangers from fire that interfere the process of evacuation. The methods used are Agent Based Modeling and Simulation (ABMS and Fire Dynamics Simulator (FDS for modeling fire simulation. Agent-Based Modeling software (pathfinder and Fire Dynamics Simulator software (pyrosim are used to calculate time evacuation in normal condition and fire condition of KM Zahro Express. Agent-Based Modeling and Simulator (ABMS is a modeling method that aims to model complex problems based on real cases. Agent-Based Modeling and Simulator (ABMS is designed to model a place that has a seat, path, exit door, humans, and others. Pyrosim is a graphical user interface for the Fire Dynamics Simulator (FDS. FDS models can predict smoke, temperature, carbon monoxide, and other substances during fires.  In this case the existing models can be used to plan and prepare an emergency if unwanted things happen. As well as using basic rules which refer to the Safety Of Life At Sea (SOLAS and International Maritime Organization (IMO. Result of Evacuation simulation calculation on emergency conditions (two rear exit doors will be closed that match at actually condition is 29,783 minutes (respon is not taken in this simulation, calculation results obtained from simulation of

  6. Deterministic integer multiple firing depending on initial state in Wang model

    Energy Technology Data Exchange (ETDEWEB)

    Xie Yong [Institute of Nonlinear Dynamics, MSSV, Department of Engineering Mechanics, Xi' an Jiaotong University, Xi' an 710049 (China)]. E-mail: yxie@mail.xjtu.edu.cn; Xu Jianxue [Institute of Nonlinear Dynamics, MSSV, Department of Engineering Mechanics, Xi' an Jiaotong University, Xi' an 710049 (China); Jiang Jun [Institute of Nonlinear Dynamics, MSSV, Department of Engineering Mechanics, Xi' an Jiaotong University, Xi' an 710049 (China)

    2006-12-15

    We investigate numerically dynamical behaviour of the Wang model, which describes the rhythmic activities of thalamic relay neurons. The model neuron exhibits Type I excitability from a global view, but Type II excitability from a local view. There exists a narrow range of bistability, in which a subthreshold oscillation and a suprathreshold firing behaviour coexist. A special firing pattern, integer multiple firing can be found in the certain part of the bistable range. The characteristic feature of such firing pattern is that the histogram of interspike intervals has a multipeaked structure, and the peaks are located at about integer multiples of a basic interspike interval. Since the Wang model is noise-free, the integer multiple firing is a deterministic firing pattern. The existence of bistability leads to the deterministic integer multiple firing depending on the initial state of the model neuron, i.e., the initial values of the state variables.

  7. Deterministic integer multiple firing depending on initial state in Wang model

    International Nuclear Information System (INIS)

    Xie Yong; Xu Jianxue; Jiang Jun

    2006-01-01

    We investigate numerically dynamical behaviour of the Wang model, which describes the rhythmic activities of thalamic relay neurons. The model neuron exhibits Type I excitability from a global view, but Type II excitability from a local view. There exists a narrow range of bistability, in which a subthreshold oscillation and a suprathreshold firing behaviour coexist. A special firing pattern, integer multiple firing can be found in the certain part of the bistable range. The characteristic feature of such firing pattern is that the histogram of interspike intervals has a multipeaked structure, and the peaks are located at about integer multiples of a basic interspike interval. Since the Wang model is noise-free, the integer multiple firing is a deterministic firing pattern. The existence of bistability leads to the deterministic integer multiple firing depending on the initial state of the model neuron, i.e., the initial values of the state variables

  8. Focus on the studies in support of fire safety analysis. IRSN modelling approach for nuclear facilities

    Energy Technology Data Exchange (ETDEWEB)

    Espargilliere, Julien; Meyrand, Raphael; Vinot, Thierry [Institut de Radioprotection et de Surete Nucleaire (IRSN), Fontenay-aux-Roses (France)

    2015-12-15

    For a fire safety analysis, in order to comply with nuclear safety goals, a nuclear fuel facility operator has to define the elements important for safety to be maintained, even in the case of a fire. One of the key points of this fire analysis is the assessment of possible fire scenarios in the facility. This paper presents the IRSN method applied to a case study to assess fire scenarios which have the most harmful effects on safety targets. The layout consists in a central room (fire cell) containing three glove boxes with radioactive material and three electrical cabinets. This room is linked to two connecting compartments (the fire cell and these two compartments define the containment cell) and then to two corridors. Each room is equipped with a mechanical ventilation system, and a pressure cascade is established from the corridors to the central room. A fire scenario was studied with fire ignition occurring in an electrical cabinet. This scenario has a set of safety goals (prevention of fire cell and containment device failure, propagation of the fire). This case study was conducted with the IRSN code SYLVIA based on two zones modelling. Safety goals were associated with key parameters and performance criteria to be fulfilled. Modelling assumptions were defined in order to maximize physical effects of the fire. Sensitivity studies were also conducted on key parameters such as oxygen limitation, equivalent-fuel definition. Eventually, a critical analysis of the code models was carried out.

  9. The Rothermel surface fire spread model and associated developments: A comprehensive explanation

    Science.gov (United States)

    Patricia L. Andrews

    2018-01-01

    The Rothermel surface fire spread model, with some adjustments by Frank A. Albini in 1976, has been used in fire and fuels management systems since 1972. It is generally used with other models including fireline intensity and flame length. Fuel models are often used to define fuel input parameters. Dynamic fuel models use equations for live fuel curing. Models have...

  10. acme: The Amendable Coal-Fire Modeling Exercise. A C++ Class Library for the Numerical Simulation of Coal-Fires

    Science.gov (United States)

    Wuttke, Manfred W.

    2017-04-01

    At LIAG, we use numerical models to develop and enhance understanding of coupled transport processes and to predict the dynamics of the system under consideration. Topics include geothermal heat utilization, subrosion processes, and spontaneous underground coal fires. Although the details make it inconvenient if not impossible to apply a single code implementation to all systems, their investigations go along similar paths: They all depend on the solution of coupled transport equations. We thus saw a need for a modular code system with open access for the various communities to maximize the shared synergistic effects. To this purpose we develop the oops! ( open object-oriented parallel solutions) - toolkit, a C++ class library for the numerical solution of mathematical models of coupled thermal, hydraulic and chemical processes. This is used to develop problem-specific libraries like acme( amendable coal-fire modeling exercise), a class library for the numerical simulation of coal-fires and applications like kobra (Kohlebrand, german for coal-fire), a numerical simulation code for standard coal-fire models. Basic principle of the oops!-code system is the provision of data types for the description of space and time dependent data fields, description of terms of partial differential equations (pde), their discretisation and solving methods. Coupling of different processes, described by their particular pde is modeled by an automatic timescale-ordered operator-splitting technique. acme is a derived coal-fire specific application library, depending on oops!. If specific functionalities of general interest are implemented and have been tested they will be assimilated into the main oops!-library. Interfaces to external pre- and post-processing tools are easily implemented. Thus a construction kit which can be arbitrarily amended is formed. With the kobra-application constructed with acme we study the processes and propagation of shallow coal seam fires in particular in

  11. Collaborative Practice Model: Improving the Delivery of Bad News.

    Science.gov (United States)

    Bowman, Pamela N; Slusser, Kim; Allen, Deborah

    2018-02-01

    Ideal bad news delivery requires skilled communication and team support. The literature has primarily focused on patient preferences, impact on care decisions, healthcare roles, and communication styles, without addressing systematic implementation. This article describes how an interdisciplinary team, led by advanced practice nurses, developed and implemented a collaborative practice model to deliver bad news on a unit that had struggled with inconsistencies. Using evidence-based practices, the authors explored current processes, role perceptions and expectations, and perceived barriers to developing the model, which is now the standard of care and an example of interprofessional team collaboration across the healthcare system. This model for delivering bad news can be easily adapted to meet the needs of other clinical units.
.

  12. A hidden Markov model approach to neuron firing patterns.

    Science.gov (United States)

    Camproux, A C; Saunier, F; Chouvet, G; Thalabard, J C; Thomas, G

    1996-11-01

    Analysis and characterization of neuronal discharge patterns are of interest to neurophysiologists and neuropharmacologists. In this paper we present a hidden Markov model approach to modeling single neuron electrical activity. Basically the model assumes that each interspike interval corresponds to one of several possible states of the neuron. Fitting the model to experimental series of interspike intervals by maximum likelihood allows estimation of the number of possible underlying neuron states, the probability density functions of interspike intervals corresponding to each state, and the transition probabilities between states. We present an application to the analysis of recordings of a locus coeruleus neuron under three pharmacological conditions. The model distinguishes two states during halothane anesthesia and during recovery from halothane anesthesia, and four states after administration of clonidine. The transition probabilities yield additional insights into the mechanisms of neuron firing.

  13. Prediction of forest fires occurrences with area-level Poisson mixed models.

    Science.gov (United States)

    Boubeta, Miguel; Lombardía, María José; Marey-Pérez, Manuel Francisco; Morales, Domingo

    2015-05-01

    The number of fires in forest areas of Galicia (north-west of Spain) during the summer period is quite high. Local authorities are interested in analyzing the factors that explain this phenomenon. Poisson regression models are good tools for describing and predicting the number of fires per forest areas. This work employs area-level Poisson mixed models for treating real data about fires in forest areas. A parametric bootstrap method is applied for estimating the mean squared errors of fires predictors. The developed methodology and software are applied to a real data set of fires in forest areas of Galicia. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. A complex-valued firing-rate model that approximates the dynamics of spiking networks.

    Directory of Open Access Journals (Sweden)

    Evan S Schaffer

    2013-10-01

    Full Text Available Firing-rate models provide an attractive approach for studying large neural networks because they can be simulated rapidly and are amenable to mathematical analysis. Traditional firing-rate models assume a simple form in which the dynamics are governed by a single time constant. These models fail to replicate certain dynamic features of populations of spiking neurons, especially those involving synchronization. We present a complex-valued firing-rate model derived from an eigenfunction expansion of the Fokker-Planck equation and apply it to the linear, quadratic and exponential integrate-and-fire models. Despite being almost as simple as a traditional firing-rate description, this model can reproduce firing-rate dynamics due to partial synchronization of the action potentials in a spiking model, and it successfully predicts the transition to spike synchronization in networks of coupled excitatory and inhibitory neurons.

  15. A complex-valued firing-rate model that approximates the dynamics of spiking networks.

    Science.gov (United States)

    Schaffer, Evan S; Ostojic, Srdjan; Abbott, L F

    2013-10-01

    Firing-rate models provide an attractive approach for studying large neural networks because they can be simulated rapidly and are amenable to mathematical analysis. Traditional firing-rate models assume a simple form in which the dynamics are governed by a single time constant. These models fail to replicate certain dynamic features of populations of spiking neurons, especially those involving synchronization. We present a complex-valued firing-rate model derived from an eigenfunction expansion of the Fokker-Planck equation and apply it to the linear, quadratic and exponential integrate-and-fire models. Despite being almost as simple as a traditional firing-rate description, this model can reproduce firing-rate dynamics due to partial synchronization of the action potentials in a spiking model, and it successfully predicts the transition to spike synchronization in networks of coupled excitatory and inhibitory neurons.

  16. Fire and Smoke Model Evaluation Experiment: Coordination of a study to improve smoke modeling for fire operations within the United States

    Science.gov (United States)

    French, N. H. F.; Ottmar, R. D.; Brown, T. J.; Larkin, N. K.

    2017-12-01

    The Fire and Smoke Model Evaluation Experiment (FASMEE) is an integrative research effort to identify and collect critical measurements to improve operational wildland fire and smoke prediction systems. FASMEE has two active phases and one suggested phase. Phase 1 is the analysis and planning process to assess the current state of fire-plume-smoke modeling and to determine the critical measurements required to evaluate and improve these operational fire and smoke models. As the major deliverable for Phase 1, a study plan has been completed that describes the measurement needs, field campaigns, and command, safety and air space de-confliction plans necessary to complete the FASMEE project. Phase 2 is a set of field campaigns to collect data during 2019-2022. Future Improvements would be a set of analyses and model improvements based on the data collected within Phase 2 that is dependent on identifying future funding sources. In this presentation, we will review the FASMEE Study Plan and detailed measurements and conditions expected for the four to five proposed research burns. The recommended measurements during Phase 2 span the four interrelated disciplines of FASMEE: fuels and consumption, fire behavior and energy, plume dynamics and meteorology, and smoke emissions, chemistry, and transport. Fuel type, condition, and consumption during wildland fire relates to several fire impacts including radiative heating, which provides the energy that drives fire dynamics. Local-scale meteorology is an important factor which relates to atmospheric chemistry, dispersion, and transport. Plume dynamics provide the connection between fire behavior and far-field smoke dispersion, because it determines the vertical distribution of the emissions. Guided by the data needs and science questions generated during Phase 1, three wildland fire campaigns were selected. These included the western wildfire campaign (rapid deployment aimed at western wildfires supporting NOAA, NASA, and NSF

  17. COMPBRN III: a computer code for modeling compartment fires

    International Nuclear Information System (INIS)

    Ho, V.; Siu, N.; Apostolakis, G.; Flanagan, G.F.

    1986-07-01

    The computer code COMPBRN III deterministically models the behavior of compartment fires. This code is an improvement of the original COMPBRN codes. It employs a different air entrainment model and numerical scheme to estimate properties of the ceiling hot gas layer model. Moreover, COMPBRN III incorporates a number of improvements in shape factor calculations and error checking, which distinguish it from the COMPBRN II code. This report presents the ceiling hot gas layer model employed by COMPBRN III as well as several other modifications. Information necessary to run COMPBRN III, including descriptions of required input and resulting output, are also presented. Simulation of experiments and a sample problem are included to demonstrate the usage of the code. 37 figs., 46 refs

  18. Modelling the impacts of reoccurring fires in tropical savannahs using Biome-BGC.

    Science.gov (United States)

    Fletcher, Charlotte; Petritsch, Richard; Pietsch, Stephan

    2010-05-01

    Fires are a dominant feature of tropical savannahs and have occurred throughout history by natural as well as human-induced means. These fires have a profound influence on the landscape in terms of flux dynamics and vegetative species composition. This study attempts to understand the impacts of fire regimes on flux dynamics and vegetation composition in savannahs using the Biome-BGC model. The Batéké Plateau, Gabon - an area of savannah grasslands in the Congo basin, serves as a case-study. To achieve model validation for savannahs, data sets from stands with differing levels of past burning are used. It is hypothesised that the field measurements from those stands with lower-levels of past burning will correlate with the Biome-BGC model output, meaning that the model is validated for the savannah excluding fire regimes. However, in reality, fire is frequent in the savannah. Data on past fire events are available from the Moderate Resolution Imaging Spectroradiometer (MODIS) to provide the fire regimes of the model. As the field data-driven measurements of the burnt stands are influenced by fire in the savannah, this will therefore result in a Biome-BGC model validated for the impacts of fire on savannah ecology. The validated model can then be used to predict the savannah's flux dynamics under the fire scenarios expected with climate and/or human impact change.

  19. The Cerro Grande Fire - From Wildfire Modeling Through the Fire Aftermath

    Energy Technology Data Exchange (ETDEWEB)

    Rudell, T. M. (Theresa M.); Gille, R. W. (Roland W.)

    2001-01-01

    The Cerro Grande Fire developed from a prescribed burn by the National Park Service at Bandelier National Monument near Los Alamos, New Mexico. When the burn went out of control and became a wildfire, it attracted worldwide attention because it threatened the birthplace of the atomic bomb, Los Alamos National Laboratory (LANL). Was LANL prepared for a fire? What lessons have been learned?

  20. The Cerro Grande Fire - From Wildlife Modeling Through the Fire Aftermath

    Energy Technology Data Exchange (ETDEWEB)

    Rudell, T. M. (Theresa M.); Gille, R. W. (Roland W.)

    2001-01-01

    The Cerro Grande Fire developed from a prescribed burn by the National Park Service at Bandelier National Monument near Los Alamos, New Mexico. When the burn went out of control and became a wildfire, it attracted worldwide attention because it threatened the birthplace of the atomic bomb, Los Alamos National Laboratory (LANL). Was LANL prepared for a fire? What lessons have been learned?

  1. Collaborative filtering recommendation model based on fuzzy clustering algorithm

    Science.gov (United States)

    Yang, Ye; Zhang, Yunhua

    2018-05-01

    As one of the most widely used algorithms in recommender systems, collaborative filtering algorithm faces two serious problems, which are the sparsity of data and poor recommendation effect in big data environment. In traditional clustering analysis, the object is strictly divided into several classes and the boundary of this division is very clear. However, for most objects in real life, there is no strict definition of their forms and attributes of their class. Concerning the problems above, this paper proposes to improve the traditional collaborative filtering model through the hybrid optimization of implicit semantic algorithm and fuzzy clustering algorithm, meanwhile, cooperating with collaborative filtering algorithm. In this paper, the fuzzy clustering algorithm is introduced to fuzzy clustering the information of project attribute, which makes the project belong to different project categories with different membership degrees, and increases the density of data, effectively reduces the sparsity of data, and solves the problem of low accuracy which is resulted from the inaccuracy of similarity calculation. Finally, this paper carries out empirical analysis on the MovieLens dataset, and compares it with the traditional user-based collaborative filtering algorithm. The proposed algorithm has greatly improved the recommendation accuracy.

  2. Rapid response tools and datasets for post-fire modeling: Linking Earth Observations and process-based hydrological models to support post-fire remediation

    Science.gov (United States)

    M. E. Miller; M. Billmire; W. J. Elliot; K. A. Endsley; P. R. Robichaud

    2015-01-01

    Preparation is key to utilizing Earth Observations and process-based models to support post-wildfire mitigation. Post-fire flooding and erosion can pose a serious threat to life, property and municipal water supplies. Increased runoff and sediment delivery due to the loss of surface cover and fire-induced changes in soil properties are of great concern. Remediation...

  3. Sustaining innovation collaboration models for a complex world

    CERN Document Server

    Carleton, Tamara

    2012-01-01

    In many ways, the process of innovation is a constant social dance, where the best dancers thrive by adapting new steps with multiple partners. The systematic and continuous generation of value in any innovation system relies on collaboration between different groups, who must overcome multiple, often competing agendas and needs to work together fruitfully over the long term. Featuring contributions from leading researchers, business leaders, and policymakers representing North America, Europe, India, Africa, and Australasia, this volume investigates different combinations of collaborative arrangements among innovation actors, many of which are changing conventional expectations of institutional relationships. Collectively, the authors demonstrate that no particular combination has emerged as the most dominant, or even resilient, model of innovation. Several authors expand on our understanding of the triple helix model, with both academics and practitioners looking to the quadruple helix (encompassing busines...

  4. Error associated with model predictions of wildland fire rate of spread

    Science.gov (United States)

    Miguel G. Cruz; Martin E. Alexander

    2015-01-01

    How well can we expect to predict the spread rate of wildfires and prescribed fires? The degree of accuracy in model predictions of wildland fire behaviour characteristics are dependent on the model's applicability to a given situation, the validity of the model's relationships, and the reliability of the model input data (Alexander and Cruz 2013b#. We...

  5. Real Time Fire Reconnaissance Satellite Monitoring System Failure Model

    Science.gov (United States)

    Nino Prieto, Omar Ariosto; Colmenares Guillen, Luis Enrique

    2013-09-01

    In this paper the Real Time Fire Reconnaissance Satellite Monitoring System is presented. This architecture is a legacy of the Detection System for Real-Time Physical Variables which is undergoing a patent process in Mexico. The methodologies for this design are the Structured Analysis for Real Time (SA- RT) [8], and the software is carried out by LACATRE (Langage d'aide à la Conception d'Application multitâche Temps Réel) [9,10] Real Time formal language. The system failures model is analyzed and the proposal is based on the formal language for the design of critical systems and Risk Assessment; AltaRica. This formal architecture uses satellites as input sensors and it was adapted from the original model which is a design pattern for physical variation detection in Real Time. The original design, whose task is to monitor events such as natural disasters and health related applications, or actual sickness monitoring and prevention, as the Real Time Diabetes Monitoring System, among others. Some related work has been presented on the Mexican Space Agency (AEM) Creation and Consultation Forums (2010-2011), and throughout the International Mexican Aerospace Science and Technology Society (SOMECYTA) international congress held in San Luis Potosí, México (2012). This Architecture will allow a Real Time Fire Satellite Monitoring, which will reduce the damage and danger caused by fires which consumes the forests and tropical forests of Mexico. This new proposal, permits having a new system that impacts on disaster prevention, by combining national and international technologies and cooperation for the benefit of humankind.

  6. Construction and Quantification of the One Top model of the Fire Events PSA

    International Nuclear Information System (INIS)

    Kang, Dae Il; Lee, Yoon Hwan; Han, Sang Hoon

    2008-01-01

    KAERI constructed the one top model of the fire events PSA for Ulchin Unit 3 and 4 by using the 'mapping technique'. The mapping technique was developed for the construction and quantification of external events PSA models with a one top model for an internal events PSA. With 'AIMS', the mapping technique can be implemented by the construction of mapping tables. The mapping tables include fire rooms, fire ignition frequency, related initiating events, fire transfer events, and the internal PSA basic events affected by a fire. The constructed one top fire PSA model is based on previously conducted fire PSA results for Ulchin Unit 3 and 4. In this paper, we introduce the construction procedure and quantification results of the one top model of the fire events PSA by using the mapping technique. As the one top model of the fire events PSA developed in this study is based on the previous study, we also introduce the previous fire PSA approach focused on quantification

  7. Review of methods for modelling forest fire risk and hazard

    African Journals Online (AJOL)

    user

    -Leal et al., 2006). Stolle and Lambin (2003) noted that flammable fuel depends on ... advantages over conventional fire detection and fire monitoring methods because ofits repetitive andconsistent coverage over large areas of land (Martin et ...

  8. Design of fire resistant concrete structures, using validated Fem models

    NARCIS (Netherlands)

    Erich, S.J.F.; Overbeek, van A.B.M.; Heijden, van der G.H.A.; Pel, L.; Huinink, H.P.; Vervuurt, A.H.J.M.; Schlangen, E.; Schlutter, de G.

    2008-01-01

    Fire safety of buildings and structures is an important issue, and has a great impact on human life and economy. One of the processes negatively affecting the strength of a concrete building or structure during fire is spalling. Many examples exists in which spalling of concrete during fire has

  9. Research and management issues in large-scale fire modeling

    Science.gov (United States)

    David L. Peterson; Daniel L. Schmoldt

    2000-01-01

    In 1996, a team of North American fire scientists and resource managers convened to assess the effects of fire disturbance on ecosystems and to develop scientific recommendations for future fire research and management activities. These recommendations - elicited with the Analytic Hierarchy Process - include numerically ranked scientific and managerial questions and...

  10. What determines area burned in large landscapes? Insights from a decade of comparative landscape-fire modelling

    Science.gov (United States)

    Geoffrey J. Cary; Robert E. Keane; Mike D. Flannigan; Ian D. Davies; Russ A. Parsons

    2015-01-01

    Understanding what determines area burned in large landscapes is critical for informing wildland fire management in fire-prone environments and for representing fire activity in Dynamic Global Vegetation Models. For the past ten years, a group of landscape-fire modellers have been exploring the relative influence of key determinants of area burned in temperate and...

  11. Developing custom fire behavior fuel models from ecologically complex fuel structures for upper Atlantic Coastal Plain forests

    Science.gov (United States)

    Bernard R. Parresol; Joe H. Scott; Anne Andreu; Susan Prichard; Laurie Kurth

    2012-01-01

    Currently geospatial fire behavior analyses are performed with an array of fire behavior modeling systems such as FARSITE, FlamMap, and the Large Fire Simulation System. These systems currently require standard or customized surface fire behavior fuel models as inputs that are often assigned through remote sensing information. The ability to handle hundreds or...

  12. Modeling forest fire occurrences using count-data mixed models in Qiannan autonomous prefecture of Guizhou province in China.

    Science.gov (United States)

    Xiao, Yundan; Zhang, Xiongqing; Ji, Ping

    2015-01-01

    Forest fires can cause catastrophic damage on natural resources. In the meantime, it can also bring serious economic and social impacts. Meteorological factors play a critical role in establishing conditions favorable for a forest fire. Effective prediction of forest fire occurrences could prevent or minimize losses. This paper uses count data models to analyze fire occurrence data which is likely to be dispersed and frequently contain an excess of zero counts (no fire occurrence). Such data have commonly been analyzed using count data models such as a Poisson model, negative binomial model (NB), zero-inflated models, and hurdle models. Data we used in this paper is collected from Qiannan autonomous prefecture of Guizhou province in China. Using the fire occurrence data from January to April (spring fire season) for the years 1996 through 2007, we introduced random effects to the count data models. In this study, the results indicated that the prediction achieved through NB model provided a more compelling and credible inferential basis for fitting actual forest fire occurrence, and mixed-effects model performed better than corresponding fixed-effects model in forest fire forecasting. Besides, among all meteorological factors, we found that relative humidity and wind speed is highly correlated with fire occurrence.

  13. Modeling anthropogenic and natural fire ignitions in an inner-alpine valley

    Directory of Open Access Journals (Sweden)

    G. Vacchiano

    2018-03-01

    Full Text Available Modeling and assessing the factors that drive forest fire ignitions is critical for fire prevention and sustainable ecosystem management. In southern Europe, the anthropogenic component of wildland fire ignitions is especially relevant. In the Alps, however, the role of fire as a component of disturbance regimes in forest and grassland ecosystems is poorly known. The aim of this work is to model the probability of fire ignition for an Alpine region in Italy using a regional wildfire archive (1995–2009 and MaxEnt modeling. We analyzed separately (i winter forest fires, (ii winter fires on grasslands and fallow land, and (iii summer fires. Predictors were related to morphology, climate, and land use; distance from infrastructures, number of farms, and number of grazing animals were used as proxies for the anthropogenic component. Collinearity among predictors was reduced by a principal component analysis. Regarding ignitions, 30 % occurred in agricultural areas and 24 % in forests. Ignitions peaked in the late winter–early spring. Negligence from agrosilvicultural activities was the main cause of ignition (64 %; lightning accounted for 9 % of causes across the study time frame, but increased from 6 to 10 % between the first and second period of analysis. Models for all groups of fire had a high goodness of fit (AUC 0.90–0.95. Temperature was proportional to the probability of ignition, and precipitation was inversely proportional. Proximity from infrastructures had an effect only on winter fires, while the density of grazing animals had a remarkably different effect on summer (positive correlation and winter (negative fires. Implications are discussed regarding climate change, fire regime changes, and silvicultural prevention. Such a spatially explicit approach allows us to carry out spatially targeted fire management strategies and may assist in developing better fire management plans.

  14. Modeling anthropogenic and natural fire ignitions in an inner-alpine valley

    Science.gov (United States)

    Vacchiano, Giorgio; Foderi, Cristiano; Berretti, Roberta; Marchi, Enrico; Motta, Renzo

    2018-03-01

    Modeling and assessing the factors that drive forest fire ignitions is critical for fire prevention and sustainable ecosystem management. In southern Europe, the anthropogenic component of wildland fire ignitions is especially relevant. In the Alps, however, the role of fire as a component of disturbance regimes in forest and grassland ecosystems is poorly known. The aim of this work is to model the probability of fire ignition for an Alpine region in Italy using a regional wildfire archive (1995-2009) and MaxEnt modeling. We analyzed separately (i) winter forest fires, (ii) winter fires on grasslands and fallow land, and (iii) summer fires. Predictors were related to morphology, climate, and land use; distance from infrastructures, number of farms, and number of grazing animals were used as proxies for the anthropogenic component. Collinearity among predictors was reduced by a principal component analysis. Regarding ignitions, 30 % occurred in agricultural areas and 24 % in forests. Ignitions peaked in the late winter-early spring. Negligence from agrosilvicultural activities was the main cause of ignition (64 %); lightning accounted for 9 % of causes across the study time frame, but increased from 6 to 10 % between the first and second period of analysis. Models for all groups of fire had a high goodness of fit (AUC 0.90-0.95). Temperature was proportional to the probability of ignition, and precipitation was inversely proportional. Proximity from infrastructures had an effect only on winter fires, while the density of grazing animals had a remarkably different effect on summer (positive correlation) and winter (negative) fires. Implications are discussed regarding climate change, fire regime changes, and silvicultural prevention. Such a spatially explicit approach allows us to carry out spatially targeted fire management strategies and may assist in developing better fire management plans.

  15. A fire suppression model for forested range of the Beverly and Qamanirjuaq herds of caribou

    Directory of Open Access Journals (Sweden)

    Donald C. Thomas

    1996-01-01

    Full Text Available A fire suppression model was developed for forested winter range of the Beverly and Qamanirjuaq (formerly Kaminuriak herds of barren-ground caribou (Rangifer tarandus groenlandicus in north-central Canada. The model is a balance between total protection, as voiced by some aboriginal people, and a let-burn policy for natural fires advocated by some ecologists. Elements in the model were caribou ecology, lichen recovery after fire, burn history, community priorities for caribou hunting, and fire cycle lengths. The percent ratio of current productive caribou habitat to the goal for that habitat determines whether fire should be suppressed in a specific area. The goals for productive caribou habitat, defined as forests older than 50 years, were scaled by fire cycle length and community priority ranking. Thus, the model is an example of co-management: traditional knowledge combined with science in a joint forum, the Beverly and Qamanirjuaq Caribou Management Board.

  16. Modeling a National Collaborative Digital Library for Malaysian Secondary Schools

    Directory of Open Access Journals (Sweden)

    N.N. Edzan

    2004-09-01

    Full Text Available This paper describes the conceptualisation of a model for a collaborative digital library specially tailored for Malaysian secondary schools, which will support classroom teaching and learning. The move towards collaboratively building the contents of a digital library is a fairly recent trend and it simulates an environment where partners are empowered to participate in building and up keeping the knowledge contents of the system. The conceptualisation of a Malaysian digital library is in line with the governments efforts in establishing SMART schools. However, various issues such as identifying local resources, ascertaining the needs of it users, and establishing a framework to meet these needs, must be addressed before the digital library can be fully implemented. It may be approached through the establishment of test beds in a particular learning institution, before nationwide implementation.

  17. Measuring behaviours for escaping from house fires: use of latent variable models to summarise multiple behaviours.

    Science.gov (United States)

    Ploubidis, G B; Edwards, P; Kendrick, D

    2015-12-15

    This paper reports the development and testing of a construct measuring parental fire safety behaviours for planning escape from a house fire. Latent variable modelling of data on parental-reported fire safety behaviours and plans for escaping from a house fire and multivariable logistic regression to quantify the association between groups defined by the latent variable modelling and parental-report of having a plan for escaping from a house fire. Data comes from 1112 participants in a cluster randomised controlled trial set in children's centres in 4 study centres in the UK. A two class model provided the best fit to the data, combining responses to five fire safety planning behaviours. The first group ('more behaviours for escaping from a house fire') comprised 86% of participants who were most likely to have a torch, be aware of how their smoke alarm sounds, to have external door and window keys accessible, and exits clear. The second group ('fewer behaviours for escaping from a house fire') comprised 14% of participants who were less likely to report these five behaviours. After adjusting for potential confounders, participants allocated to the 'more behaviours for escaping from a house fire group were 2.5 times more likely to report having an escape plan (OR 2.48; 95% CI 1.59-3.86) than those in the "fewer behaviours for escaping from a house fire" group. Multiple fire safety behaviour questions can be combined into a single binary summary measure of fire safety behaviours for escaping from a house fire. Our findings will be useful to future studies wishing to use a single measure of fire safety planning behaviour as measures of outcome or exposure. NCT 01452191. Date of registration 13/10/2011.

  18. [Prediction model of human-caused fire occurrence in the boreal forest of northern China].

    Science.gov (United States)

    Guo, Fu-tao; Su, Zhang-wen; Wang, Guang-yu; Wang, Qiang; Sun, Long; Yang, Ting-ting

    2015-07-01

    The Chinese boreal forest is an important forest resource in China. However, it has been suffering serious disturbances of forest fires, which were caused equally by natural disasters (e.g., lightning) and human activities. The literature on human-caused fires indicates that climate, topography, vegetation, and human infrastructure are significant factors that impact the occurrence and spread of human-caused fires. But the studies on human-caused fires in the boreal forest of northern China are limited and less comprehensive. This paper applied the spatial analysis tools in ArcGIS 10.0 and Logistic regression model to investigate the driving factors of human-caused fires. Our data included the geographic coordinates of human-caused fires, climate factors during year 1974-2009, topographic information, and forest map. The results indicated that distance to railway (x1) and average relative humidity (x2) significantly impacted the occurrence of human-caused fire in the study area. The logistic model for predicting the fire occurrence probability was formulated as P= 1/[11+e-(3.026-0.00011x1-0.047x2)] with an accuracy rate of 80%. The above model was used to predict the monthly fire occurrence during the fire season of 2015 based on the HADCM2 future weather data. The prediction results showed that the high risk of human-caused fire occurrence concentrated in the months of April, May, June and August, while April and May had higher risk of fire occurrence than other months. According to the spatial distribution of possibility of fire occurrence, the high fire risk zones were mainly in the west and southwest of Tahe, where the major railways were located.

  19. Cyberinfrastructure to Support Collaborative and Reproducible Computational Hydrologic Modeling

    Science.gov (United States)

    Goodall, J. L.; Castronova, A. M.; Bandaragoda, C.; Morsy, M. M.; Sadler, J. M.; Essawy, B.; Tarboton, D. G.; Malik, T.; Nijssen, B.; Clark, M. P.; Liu, Y.; Wang, S. W.

    2017-12-01

    Creating cyberinfrastructure to support reproducibility of computational hydrologic models is an important research challenge. Addressing this challenge requires open and reusable code and data with machine and human readable metadata, organized in ways that allow others to replicate results and verify published findings. Specific digital objects that must be tracked for reproducible computational hydrologic modeling include (1) raw initial datasets, (2) data processing scripts used to clean and organize the data, (3) processed model inputs, (4) model results, and (5) the model code with an itemization of all software dependencies and computational requirements. HydroShare is a cyberinfrastructure under active development designed to help users store, share, and publish digital research products in order to improve reproducibility in computational hydrology, with an architecture supporting hydrologic-specific resource metadata. Researchers can upload data required for modeling, add hydrology-specific metadata to these resources, and use the data directly within HydroShare.org for collaborative modeling using tools like CyberGIS, Sciunit-CLI, and JupyterHub that have been integrated with HydroShare to run models using notebooks, Docker containers, and cloud resources. Current research aims to implement the Structure For Unifying Multiple Modeling Alternatives (SUMMA) hydrologic model within HydroShare to support hypothesis-driven hydrologic modeling while also taking advantage of the HydroShare cyberinfrastructure. The goal of this integration is to create the cyberinfrastructure that supports hypothesis-driven model experimentation, education, and training efforts by lowering barriers to entry, reducing the time spent on informatics technology and software development, and supporting collaborative research within and across research groups.

  20. The Healthy Aging Research Network: Modeling Collaboration for Community Impact.

    Science.gov (United States)

    Belza, Basia; Altpeter, Mary; Smith, Matthew Lee; Ory, Marcia G

    2017-03-01

    As the first Centers for Disease Control and Prevention (CDC) Prevention Research Centers Program thematic network, the Healthy Aging Research Network was established to better understand the determinants of healthy aging within older adult populations, identify interventions that promote healthy aging, and assist in translating research into sustainable community-based programs throughout the nation. To achieve these goals requires concerted efforts of a collaborative network of academic, community, and public health organizational partnerships. For the 2001-2014 Prevention Research Center funding cycles, the Healthy Aging Research Network conducted prevention research and promoted the wide use of practices known to foster optimal health. Organized around components necessary for successful collaborations (i.e., governance and infrastructure, shaping focus, community involvement, and evaluation and improvement), this commentary highlights exemplars that demonstrate the Healthy Aging Research Network's unique contributions to the field. The Healthy Aging Research Network's collaboration provided a means to collectively build capacity for practice and policy, reduce fragmentation and duplication in health promotion and aging research efforts, maximize the efficient use of existing resources and generate additional resources, and ultimately, create synergies for advancing the healthy aging agenda. This collaborative model was built upon a backbone organization (coordinating center); setting of common agendas and mutually reinforcing activities; and continuous communications. Given its successes, the Healthy Aging Research Network model could be used to create new and evaluate existing thematic networks to guide the translation of research into policy and practice. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  1. Development of a Base Model for the New Fire PSA Training

    International Nuclear Information System (INIS)

    Kim, Kilyoo; Kang, Daeil; Kim, Wee Kyong; Do, Kyu Sik

    2013-01-01

    US NRC/EPRI issued a new fire PSA method represented by NUREG/CR 6850, and have been training many operators and inspectors to widely spread the new method. However, there is a limitation in time and efficiency for many foreigners, who generally have communication problem, to participate in the EPRI/NRC training to learn the new method. Since it is about time to introduce the new fire PSA method as a regulatory requirement for the fire protection in Korea, a simple and easy-understandable base model for the fire PSA training is required, and KAERI-KINS is jointly preparing the base model for the new fire PSA training. This paper describes how the base model is developed. Using an imaginary simple NPP, a base model of fire PSA following the new fire PSA method was developed in two ways from the internal PSA model. Since we have the base model and know the process of making the fire PSA model, the training for the new fire PSA method can be in detail performed in Korea

  2. EMPIRICAL MODELS FOR DESCRIBING FIRE BEHAVIOR IN BRAZILIAN COMMERCIAL EUCALYPT PLANTATIONS

    Directory of Open Access Journals (Sweden)

    Benjamin Leonardo Alves White

    2016-12-01

    Full Text Available Modeling forest fire behavior is an important task that can be used to assist in fire prevention and suppression operations. However, according to previous studies, the existing common worldwide fire behavior models used do not correctly estimate the fire behavior in Brazilian commercial hybrid eucalypt plantations. Therefore, this study aims to build new empirical models to predict the fire rate of spread, flame length and fuel consumption for such vegetation. To meet these objectives, 105 laboratory experimental burns were done, where the main fuel characteristics and weather variables that influence fire behavior were controlled and/or measured in each experiment. Dependent and independent variables were fitted through multiple regression analysis. The fire rate of spread proposed model is based on the wind speed, fuel bed bulk density and 1-h dead fuel moisture content (r2 = 0.86; the flame length model is based on the fuel bed depth, 1-h dead fuel moisture content and wind speed (r2 = 0.72; the fuel consumption proposed model has the 1-h dead fuel moisture, fuel bed bulk density and 1-h dead dry fuel load as independent variables (r2= 0.80. These models were used to develop a new fire behavior software, the “Eucalyptus Fire Safety System”.

  3. Obtaining a Pragmatic Representation of Fire Disturbance in Dynamic Vegetation Models by Assimilating Earth Observation Data

    Science.gov (United States)

    Kantzas, Euripides; Quegan, Shaun

    2015-04-01

    Fire constitutes a violent and unpredictable pathway of carbon from the terrestrial biosphere into the atmosphere. Despite fire emissions being in many biomes of similar magnitude to that of Net Ecosystem Exchange, even the most complex Dynamic Vegetation Models (DVMs) embedded in IPCC General Circulation Models poorly represent fire behavior and dynamics, a fact which still remains understated. As DVMs operate on a deterministic, grid cell-by-grid cell basis they are unable to describe a host of important fire characteristics such as its propagation, magnitude of area burned and stochastic nature. Here we address these issues by describing a model-independent methodology which assimilates Earth Observation (EO) data by employing image analysis techniques and algorithms to offer a realistic fire disturbance regime in a DVM. This novel approach, with minimum model restructuring, manages to retain the Fire Return Interval produced by the model whilst assigning pragmatic characteristics to its fire outputs thus allowing realistic simulations of fire-related processes such as carbon injection into the atmosphere and permafrost degradation. We focus our simulations in the Arctic and specifically Canada and Russia and we offer a snippet of how this approach permits models to engage in post-fire dynamics hitherto absent from any other model regardless of complexity.

  4. Burnthrough Modeling of Marine Grade Aluminum Alloy Structural Plates Exposed to Fire

    OpenAIRE

    Rippe, Christian M

    2015-01-01

    Current fire induced burnthrough models of aluminum typically rely solely on temperature thresholds and cannot accurately capture either the occurrence or the time to burnthrough. This research experimentally explores the fire induced burnthrough phenomenon of AA6061-T651 plates under multiple sized exposures and introduces a new burnthrough model based on the near melting creep rupture properties of the material. Fire experiments to induce burnthrough on aluminum plates were conducted us...

  5. Caliver: An R package for CALIbration and VERification of forest fire gridded model outputs.

    Science.gov (United States)

    Vitolo, Claudia; Di Giuseppe, Francesca; D'Andrea, Mirko

    2018-01-01

    The name caliver stands for CALIbration and VERification of forest fire gridded model outputs. This is a package developed for the R programming language and available under an APACHE-2 license from a public repository. In this paper we describe the functionalities of the package and give examples using publicly available datasets. Fire danger model outputs are taken from the modeling components of the European Forest Fire Information System (EFFIS) and observed burned areas from the Global Fire Emission Database (GFED). Complete documentation, including a vignette, is also available within the package.

  6. Calibrating a forest landscape model to simulate frequent fire in Mediterranean-type shrublands

    Science.gov (United States)

    Syphard, A.D.; Yang, J.; Franklin, J.; He, H.S.; Keeley, J.E.

    2007-01-01

    In Mediterranean-type ecosystems (MTEs), fire disturbance influences the distribution of most plant communities, and altered fire regimes may be more important than climate factors in shaping future MTE vegetation dynamics. Models that simulate the high-frequency fire and post-fire response strategies characteristic of these regions will be important tools for evaluating potential landscape change scenarios. However, few existing models have been designed to simulate these properties over long time frames and broad spatial scales. We refined a landscape disturbance and succession (LANDIS) model to operate on an annual time step and to simulate altered fire regimes in a southern California Mediterranean landscape. After developing a comprehensive set of spatial and non-spatial variables and parameters, we calibrated the model to simulate very high fire frequencies and evaluated the simulations under several parameter scenarios representing hypotheses about system dynamics. The goal was to ensure that observed model behavior would simulate the specified fire regime parameters, and that the predictions were reasonable based on current understanding of community dynamics in the region. After calibration, the two dominant plant functional types responded realistically to different fire regime scenarios. Therefore, this model offers a new alternative for simulating altered fire regimes in MTE landscapes. ?? 2007 Elsevier Ltd. All rights reserved.

  7. Forest fire effects on transpiration: process modeling of sapwood area reduction

    Science.gov (United States)

    Michaletz, Sean; Johnson, Edward

    2010-05-01

    Transpiration is a hydrological process that is strongly affected by forest fires. In crown fires, canopy fine fuels (foliage, buds, and small branches) combust, which kills individual trees and stops transpiration of the entire stand. In surface fires (intensities ≤ 2500 kW m-1), however, effects on transpiration are less predictable becuase heat transfer from the passing fireline can injure or kill fine roots, leaves, and sapwood; post-fire transpiration of forest stands is thus governed by fire effects on individual tree water budgets. Here, we consider fire effects on cross-sectional sapwood area. A two-dimensional model of transient bole heating is used to estimate radial isotherms for a range of fireline intensities typical of surface fires. Isotherms are then used to drive three processes by which heat may reduce sapwood area: 1) necrosis of living cells in contact with xylem conduits, which prevents repair of natural embolism; 2) relaxation of viscoelastic conduit wall polymers (cellulose, hemicelloluse, and lignin), which reduces cross-sectional conduit area; and 3) boiling of metastable water under tension, which causes conduit embolism. Results show that these processes operate on different time scales, suggesting that fire effects on transpiration vary with time since fire. The model can be linked with a three-dimensional physical fire spread model to predict size-dependent effects on individual trees, which can be used to estimate scaling of individual tree and stand-level transpiration.

  8. Numerical modeling of water spray suppression of conveyor belt fires in a large-scale tunnel.

    Science.gov (United States)

    Yuan, Liming; Smith, Alex C

    2015-05-01

    Conveyor belt fires in an underground mine pose a serious life threat to miners. Water sprinkler systems are usually used to extinguish underground conveyor belt fires, but because of the complex interaction between conveyor belt fires and mine ventilation airflow, more effective engineering designs are needed for the installation of water sprinkler systems. A computational fluid dynamics (CFD) model was developed to simulate the interaction between the ventilation airflow, the belt flame spread, and the water spray system in a mine entry. The CFD model was calibrated using test results from a large-scale conveyor belt fire suppression experiment. Simulations were conducted using the calibrated CFD model to investigate the effects of sprinkler location, water flow rate, and sprinkler activation temperature on the suppression of conveyor belt fires. The sprinkler location and the activation temperature were found to have a major effect on the suppression of the belt fire, while the water flow rate had a minor effect.

  9. Reconstruction of fire regimes through integrated paleoecological proxy data and ecological modeling.

    Science.gov (United States)

    Iglesias, Virginia; Yospin, Gabriel I; Whitlock, Cathy

    2014-01-01

    Fire is a key ecological process affecting vegetation dynamics and land cover. The characteristic frequency, size, and intensity of fire are driven by interactions between top-down climate-driven and bottom-up fuel-related processes. Disentangling climatic from non-climatic drivers of past fire regimes is a grand challenge in Earth systems science, and a topic where both paleoecology and ecological modeling have made substantial contributions. In this manuscript, we (1) review the use of sedimentary charcoal as a fire proxy and the methods used in charcoal-based fire history reconstructions; (2) identify existing techniques for paleoecological modeling; and (3) evaluate opportunities for coupling of paleoecological and ecological modeling approaches to better understand the causes and consequences of past, present, and future fire activity.

  10. Numerical modeling of water spray suppression of conveyor belt fires in a large-scale tunnel

    Science.gov (United States)

    Yuan, Liming; Smith, Alex C.

    2015-01-01

    Conveyor belt fires in an underground mine pose a serious life threat to miners. Water sprinkler systems are usually used to extinguish underground conveyor belt fires, but because of the complex interaction between conveyor belt fires and mine ventilation airflow, more effective engineering designs are needed for the installation of water sprinkler systems. A computational fluid dynamics (CFD) model was developed to simulate the interaction between the ventilation airflow, the belt flame spread, and the water spray system in a mine entry. The CFD model was calibrated using test results from a large-scale conveyor belt fire suppression experiment. Simulations were conducted using the calibrated CFD model to investigate the effects of sprinkler location, water flow rate, and sprinkler activation temperature on the suppression of conveyor belt fires. The sprinkler location and the activation temperature were found to have a major effect on the suppression of the belt fire, while the water flow rate had a minor effect. PMID:26190905

  11. Interprofessional collaboration: three best practice models of interprofessional education

    Directory of Open Access Journals (Sweden)

    Diane R. Bridges

    2011-04-01

    Full Text Available Interprofessional education is a collaborative approach to develop healthcare students as future interprofessional team members and a recommendation suggested by the Institute of Medicine. Complex medical issues can be best addressed by interprofessional teams. Training future healthcare providers to work in such teams will help facilitate this model resulting in improved healthcare outcomes for patients. In this paper, three universities, the Rosalind Franklin University of Medicine and Science, the University of Florida and the University of Washington describe their training curricula models of collaborative and interprofessional education.The models represent a didactic program, a community-based experience and an interprofessional-simulation experience. The didactic program emphasizes interprofessional team building skills, knowledge of professions, patient centered care, service learning, the impact of culture on healthcare delivery and an interprofessional clinical component. The community-based experience demonstrates how interprofessional collaborations provide service to patients and how the environment and availability of resources impact one's health status. The interprofessional-simulation experience describes clinical team skills training in both formative and summative simulations used to develop skills in communication and leadership.One common theme leading to a successful experience among these three interprofessional models included helping students to understand their own professional identity while gaining an understanding of other professional's roles on the health care team. Commitment from departments and colleges, diverse calendar agreements, curricular mapping, mentor and faculty training, a sense of community, adequate physical space, technology, and community relationships were all identified as critical resources for a successful program. Summary recommendations for best practices included the need for administrative

  12. Interprofessional collaboration: three best practice models of interprofessional education.

    Science.gov (United States)

    Bridges, Diane R; Davidson, Richard A; Odegard, Peggy Soule; Maki, Ian V; Tomkowiak, John

    2011-04-08

    Interprofessional education is a collaborative approach to develop healthcare students as future interprofessional team members and a recommendation suggested by the Institute of Medicine. Complex medical issues can be best addressed by interprofessional teams. Training future healthcare providers to work in such teams will help facilitate this model resulting in improved healthcare outcomes for patients. In this paper, three universities, the Rosalind Franklin University of Medicine and Science, the University of Florida and the University of Washington describe their training curricula models of collaborative and interprofessional education.The models represent a didactic program, a community-based experience and an interprofessional-simulation experience. The didactic program emphasizes interprofessional team building skills, knowledge of professions, patient centered care, service learning, the impact of culture on healthcare delivery and an interprofessional clinical component. The community-based experience demonstrates how interprofessional collaborations provide service to patients and how the environment and availability of resources impact one's health status. The interprofessional-simulation experience describes clinical team skills training in both formative and summative simulations used to develop skills in communication and leadership.One common theme leading to a successful experience among these three interprofessional models included helping students to understand their own professional identity while gaining an understanding of other professional's roles on the health care team. Commitment from departments and colleges, diverse calendar agreements, curricular mapping, mentor and faculty training, a sense of community, adequate physical space, technology, and community relationships were all identified as critical resources for a successful program. Summary recommendations for best practices included the need for administrative support

  13. Interprofessional collaboration: three best practice models of interprofessional education

    Science.gov (United States)

    Bridges, Diane R.; Davidson, Richard A.; Odegard, Peggy Soule; Maki, Ian V.; Tomkowiak, John

    2011-01-01

    Interprofessional education is a collaborative approach to develop healthcare students as future interprofessional team members and a recommendation suggested by the Institute of Medicine. Complex medical issues can be best addressed by interprofessional teams. Training future healthcare providers to work in such teams will help facilitate this model resulting in improved healthcare outcomes for patients. In this paper, three universities, the Rosalind Franklin University of Medicine and Science, the University of Florida and the University of Washington describe their training curricula models of collaborative and interprofessional education. The models represent a didactic program, a community-based experience and an interprofessional-simulation experience. The didactic program emphasizes interprofessional team building skills, knowledge of professions, patient centered care, service learning, the impact of culture on healthcare delivery and an interprofessional clinical component. The community-based experience demonstrates how interprofessional collaborations provide service to patients and how the environment and availability of resources impact one's health status. The interprofessional-simulation experience describes clinical team skills training in both formative and summative simulations used to develop skills in communication and leadership. One common theme leading to a successful experience among these three interprofessional models included helping students to understand their own professional identity while gaining an understanding of other professional's roles on the health care team. Commitment from departments and colleges, diverse calendar agreements, curricular mapping, mentor and faculty training, a sense of community, adequate physical space, technology, and community relationships were all identified as critical resources for a successful program. Summary recommendations for best practices included the need for administrative support

  14. Evaluating intersectoral collaboration: a model for assessment by service users

    Directory of Open Access Journals (Sweden)

    Bengt Ahgren

    2009-02-01

    Full Text Available Introduction: DELTA was launched as a project in 1997 to improve intersectoral collaboration in the rehabilitation field. In 2005 DELTA was transformed into a local association for financial co-ordination between the institutions involved. Based on a study of the DELTA service users, the purpose of this article is to develop and to validate a model that can be used to assess the integration of welfare services from the perspective of the service users. Theory: The foundation of integration is a well functioning structure of integration. Without such structural conditions, it is difficult to develop a process of integration that combines the resources and competences of the collaborating organisations to create services advantageous for the service users. In this way, both the structure and the process will contribute to the outcome of integration. Method: The study was carried out as a retrospective cross-sectional survey during two weeks, including all the current service users of DELTA. The questionnaire contained 32 questions, which were derived from the theoretical framework and research on service users, capturing perceptions of integration structure, process and outcome. Ordinal scales and open questions where used for the assessment. Results: The survey had a response rate of 82% and no serious biases of the results were detected. The study shows that the users of the rehabilitation services perceived the services as well integrated, relevant and adapted to their needs. The assessment model was tested for reliability and validity and a few modifications were suggested. Some key measurement themes were derived from the study. Conclusion: The model developed in this study is an important step towards an assessment of service integration from the perspective of the service users. It needs to be further refined, however, before it can be used in other evaluations of collaboration in the provision of integrated welfare services.

  15. BEHAVE: fire behavior prediction and fuel modeling system-BURN Subsystem, part 1

    Science.gov (United States)

    Patricia L. Andrews

    1986-01-01

    Describes BURN Subsystem, Part 1, the operational fire behavior prediction subsystem of the BEHAVE fire behavior prediction and fuel modeling system. The manual covers operation of the computer program, assumptions of the mathematical models used in the calculations, and application of the predictions.

  16. Evaluating crown fire rate of spread predictions from physics-based models

    Science.gov (United States)

    C. M. Hoffman; J. Ziegler; J. Canfield; R. R. Linn; W. Mell; C. H. Sieg; F. Pimont

    2015-01-01

    Modeling the behavior of crown fires is challenging due to the complex set of coupled processes that drive the characteristics of a spreading wildfire and the large range of spatial and temporal scales over which these processes occur. Detailed physics-based modeling approaches such as FIRETEC and the Wildland Urban Interface Fire Dynamics Simulator (WFDS) simulate...

  17. Tunnel fire testing and modeling the Morgex North tunnel experiment

    CERN Document Server

    Borghetti, Fabio; Gandini, Paolo; Frassoldati, Alessio; Tavelli, Silvia

    2017-01-01

    This book aims to cast light on all aspects of tunnel fires, based on experimental activities and theoretical and computational fluid dynamics (CFD) analyses. In particular, the authors describe a transient full-scale fire test (~15 MW), explaining how they designed and performed the experimental activity inside the Morgex North tunnel in Italy. The entire organization of the experiment is described, from preliminary evaluations to the solutions found for management of operational difficulties and safety issues. This fire test allowed the collection of different measurements (temperature, air velocity, smoke composition, pollutant species) useful for validating and improving CFD codes and for testing the real behavior of the tunnel and its safety systems during a diesel oil fire with a significant heat release rate. Finally, the fire dynamics are compared with empirical correlations, CFD simulations, and literature measurements obtained in other similar tunnel fire tests. This book will be of interest to all ...

  18. Fire, ice, water, and dirt: A simple climate model

    Science.gov (United States)

    Kroll, John

    2017-07-01

    A simple paleoclimate model was developed as a modeling exercise. The model is a lumped parameter system consisting of an ocean (water), land (dirt), glacier, and sea ice (ice) and driven by the sun (fire). In comparison with other such models, its uniqueness lies in its relative simplicity yet yielding good results. For nominal values of parameters, the system is very sensitive to small changes in the parameters, yielding equilibrium, steady oscillations, and catastrophes such as freezing or boiling oceans. However, stable solutions can be found, especially naturally oscillating solutions. For nominally realistic conditions, natural periods of order 100kyrs are obtained, and chaos ensues if the Milankovitch orbital forcing is applied. An analysis of a truncated system shows that the naturally oscillating solution is a limit cycle with the characteristics of a relaxation oscillation in the two major dependent variables, the ocean temperature and the glacier ice extent. The key to getting oscillations is having the effective emissivity decreasing with temperature and, at the same time, the effective ocean albedo decreases with increasing glacier extent. Results of the original model compare favorably to the proxy data for ice mass variation, but not for temperature variation. However, modifications to the effective emissivity and albedo can be made to yield much more realistic results. The primary conclusion is that the opinion of Saltzman [Clim. Dyn. 5, 67-78 (1990)] is plausible that the external Milankovitch orbital forcing is not sufficient to explain the dominant 100kyr period in the data.

  19. Fire, ice, water, and dirt: A simple climate model.

    Science.gov (United States)

    Kroll, John

    2017-07-01

    A simple paleoclimate model was developed as a modeling exercise. The model is a lumped parameter system consisting of an ocean (water), land (dirt), glacier, and sea ice (ice) and driven by the sun (fire). In comparison with other such models, its uniqueness lies in its relative simplicity yet yielding good results. For nominal values of parameters, the system is very sensitive to small changes in the parameters, yielding equilibrium, steady oscillations, and catastrophes such as freezing or boiling oceans. However, stable solutions can be found, especially naturally oscillating solutions. For nominally realistic conditions, natural periods of order 100kyrs are obtained, and chaos ensues if the Milankovitch orbital forcing is applied. An analysis of a truncated system shows that the naturally oscillating solution is a limit cycle with the characteristics of a relaxation oscillation in the two major dependent variables, the ocean temperature and the glacier ice extent. The key to getting oscillations is having the effective emissivity decreasing with temperature and, at the same time, the effective ocean albedo decreases with increasing glacier extent. Results of the original model compare favorably to the proxy data for ice mass variation, but not for temperature variation. However, modifications to the effective emissivity and albedo can be made to yield much more realistic results. The primary conclusion is that the opinion of Saltzman [Clim. Dyn. 5, 67-78 (1990)] is plausible that the external Milankovitch orbital forcing is not sufficient to explain the dominant 100kyr period in the data.

  20. Computational fluid dynamics in fire engineering theory, modelling and practice

    CERN Document Server

    Yuen, Kwok Kit

    2009-01-01

    Fire and combustion presents a significant engineering challenge to mechanical, civil and dedicated fire engineers, as well as specialists in the process and chemical, safety, buildings and structural fields. We are reminded of the tragic outcomes of 'untenable' fire disasters such as at King's Cross underground station or Switzerland's St Gotthard tunnel. In these and many other cases, computational fluid dynamics (CFD) is at the forefront of active research into unravelling the probable causes of fires and helping to design structures and systems to ensure that they are less likely in the f

  1. Numerical modeling of laboratory-scale surface-to-crown fire transition

    Science.gov (United States)

    Castle, Drew Clayton

    Understanding the conditions leading to the transition of fire spread from a surface fuel to an elevated (crown) fuel is critical to effective fire risk assessment and management. Surface fires that successfully transition to crown fires can be very difficult to suppress, potentially leading to damages in the natural and built environments. This is relevant to chaparral shrub lands which are common throughout parts of the Southwest U.S. and represent a significant part of the wildland urban interface. The ability of the Wildland-Urban Interface Fire Dynamic Simulator (WFDS) to model surface-to-crown fire transition was evaluated through comparison to laboratory experiments. The WFDS model is being developed by the U.S. Forest Service (USFS) and the National Institute of Standards and Technology. The experiments were conducted at the USFS Forest Fire Laboratory in Riverside, California. The experiments measured the ignition of chamise (Adenostoma fasciculatum) crown fuel held above a surface fire spreading through excelsior fuel. Cases with different crown fuel bulk densities, crown fuel base heights, and imposed wind speeds were considered. Cold-flow simulations yielded wind speed profiles that closely matched the experimental measurements. Next, fire simulations with only the surface fuel were conducted to verify the rate of spread while factors such as substrate properties were varied. Finally, simulations with both a surface fuel and a crown fuel were completed. Examination of specific surface fire characteristics (rate of spread, flame angle, etc.) and the corresponding experimental surface fire behavior provided a basis for comparison of the factors most responsible for transition from a surface fire to the raised fuel ignition. The rate of spread was determined by tracking the flame in the Smokeview animations using a tool developed for tracking an actual flame in a video. WFDS simulations produced results in both surface fire spread and raised fuel bed

  2. Modeling In-Stream Hydro-Geomorphic Processes After 2012 Waldo Canyon Fire, Colorado

    Science.gov (United States)

    Nourbakhshbeidokhti, S.; Kinoshita, A. M.; Chin, A.

    2016-12-01

    Wildfires can have significant impacts on hydrologic and geomorphic processes. Post-fire sediment transport and runoff generation vary by burn severity, precipitation, and vegetation. A need exists to understand these variable relationships and improve parameterization of post-fire hydro-geomorphic models. This research aims to model pre-fire geomorphic and hydrologic processes in Williams Canyon, a watershed burned by the 2012 Waldo Canyon Fire in Colorado. We develop the KINematic Runoff and EROSion (KINEROS) model with Geographical Information System (GIS)-based information, including a Digital Elevation Model, land cover, soil classification, precipitation, and soil burn severity for a local reference watershed that is unburned. We transfer these parameters to a channel reach in Williams Canyon (Williams Downstream) and adjust them toward post-fire conditions. We model runoff and sediment yield for several storms following the fire. Three post-fire terrestrial Light Detection and Ranging (LiDAR) images (21 April 2013, 14 September 2013, and 16 September 2014) are used to estimate total erosion and deposition at the reach scale. We use the LiDAR-based information to calibrate the post-fire model. Preliminary modeling results indicate 3870-125 kg/ha of sediment in the Williams Downstream reach. The uncalibrated model overestimated (410% in the first year) and underestimated (87.2% in the second year) the erosion. Model calibration reduced the Root Mean Square Error (RMSE) of sediment to 0.016% for the first year and 0.09% for the second year. The parameters calibrated for the Williams Downstream channel reach will be used to develop models for seven other channel reaches within the area burned by the Waldo Canyon Fire, where the performance can be evaluated with LiDAR estimates. Results of this research will enhance our understanding of wildfire disturbance on coupled hydrologic and geomorphic processes. Findings will also improve model parameterization that can

  3. Linen Fire as Biosorbent to Remove Heavy Metal Ions From Wastewater Modeling

    OpenAIRE

    Ildar G. Shaikhiev

    2014-01-01

    The possibility of using linen fires – lnopererabotk i waste as a sorption material for the extraction of heavy metal ions from wastewater modeling. It is shown that treatment with acid solutions linen fires a low concentration increases the surface area of linen fires and thus sorption capacity for heavy metal ions. The values of the maximum sorption capacity ions Fe (III), Co (II), Ni (II) and Zn (II) under static and dynamic conditions. IR spectroscopy...

  4. Evaluation of a collaborative model: a case study analysis of watershed planning in the intermountain west

    Science.gov (United States)

    Gary Bentrup

    2001-01-01

    Collaborative planning processes have become increasingly popular for addressing environmental planning issues, resulting in a number of conceptual models for collaboration. A model proposed by Selin and Chavez suggests that collaboration emerges from a series of antecedents and then proceeds sequentially through problem-setting, direction-setting, implementation, and...

  5. Rethinking Design Process: Using 3D Digital Models as an Interface in Collaborative Session

    Science.gov (United States)

    Ding, Suining

    2008-01-01

    This paper describes a pilot study for an alternative design process by integrating a designer-user collaborative session with digital models. The collaborative session took place in a 3D AutoCAD class for a real world project. The 3D models served as an interface for designer-user collaboration during the design process. Students not only learned…

  6. A University/Community Collaborative Model on Empowerment in Elementary Education.

    Science.gov (United States)

    Goeke, John C.; And Others

    1995-01-01

    Collaboration is growing among schools and community services for youth, their families, and now, university graduate programs. Proposes a structural model for collaboration which implements the concept of empowerment and designs sustainable working relationships over time. (DR)

  7. Implementation & Flight Testing of IMPACT system for Autonomous ISR using Collaborating UAVs with Application to Wild Fire Monitoring, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — SSCI and MIT propose to further develop, implement and test the Integrated Mission Planning (ii) Robust on-line learning for prediction of the fire spread using the...

  8. Incorporating Anthropogenic Influences into Fire Probability Models: Effects of Human Activity and Climate Change on Fire Activity in California.

    Science.gov (United States)

    Mann, Michael L; Batllori, Enric; Moritz, Max A; Waller, Eric K; Berck, Peter; Flint, Alan L; Flint, Lorraine E; Dolfi, Emmalee

    2016-01-01

    The costly interactions between humans and wildfires throughout California demonstrate the need to understand the relationships between them, especially in the face of a changing climate and expanding human communities. Although a number of statistical and process-based wildfire models exist for California, there is enormous uncertainty about the location and number of future fires, with previously published estimates of increases ranging from nine to fifty-three percent by the end of the century. Our goal is to assess the role of climate and anthropogenic influences on the state's fire regimes from 1975 to 2050. We develop an empirical model that integrates estimates of biophysical indicators relevant to plant communities and anthropogenic influences at each forecast time step. Historically, we find that anthropogenic influences account for up to fifty percent of explanatory power in the model. We also find that the total area burned is likely to increase, with burned area expected to increase by 2.2 and 5.0 percent by 2050 under climatic bookends (PCM and GFDL climate models, respectively). Our two climate models show considerable agreement, but due to potential shifts in rainfall patterns, substantial uncertainty remains for the semiarid inland deserts and coastal areas of the south. Given the strength of human-related variables in some regions, however, it is clear that comprehensive projections of future fire activity should include both anthropogenic and biophysical influences. Previous findings of substantially increased numbers of fires and burned area for California may be tied to omitted variable bias from the exclusion of human influences. The omission of anthropogenic variables in our model would overstate the importance of climatic ones by at least 24%. As such, the failure to include anthropogenic effects in many models likely overstates the response of wildfire to climatic change.

  9. Incorporating Anthropogenic Influences into Fire Probability Models: Effects of Human Activity and Climate Change on Fire Activity in California.

    Directory of Open Access Journals (Sweden)

    Michael L Mann

    Full Text Available The costly interactions between humans and wildfires throughout California demonstrate the need to understand the relationships between them, especially in the face of a changing climate and expanding human communities. Although a number of statistical and process-based wildfire models exist for California, there is enormous uncertainty about the location and number of future fires, with previously published estimates of increases ranging from nine to fifty-three percent by the end of the century. Our goal is to assess the role of climate and anthropogenic influences on the state's fire regimes from 1975 to 2050. We develop an empirical model that integrates estimates of biophysical indicators relevant to plant communities and anthropogenic influences at each forecast time step. Historically, we find that anthropogenic influences account for up to fifty percent of explanatory power in the model. We also find that the total area burned is likely to increase, with burned area expected to increase by 2.2 and 5.0 percent by 2050 under climatic bookends (PCM and GFDL climate models, respectively. Our two climate models show considerable agreement, but due to potential shifts in rainfall patterns, substantial uncertainty remains for the semiarid inland deserts and coastal areas of the south. Given the strength of human-related variables in some regions, however, it is clear that comprehensive projections of future fire activity should include both anthropogenic and biophysical influences. Previous findings of substantially increased numbers of fires and burned area for California may be tied to omitted variable bias from the exclusion of human influences. The omission of anthropogenic variables in our model would overstate the importance of climatic ones by at least 24%. As such, the failure to include anthropogenic effects in many models likely overstates the response of wildfire to climatic change.

  10. The Feasibility of Multiscale Modeling of Tunnel Fires Using FDS 6

    DEFF Research Database (Denmark)

    Vermesi, Izabella; Colella, Francesco; Rein, Guillermo

    2014-01-01

    The HVAC component of FDS 6 was used to divide a 1.2km tunnel into a 3D near fire area and a 1D area further away from the fire in order to investigate the feasibility of multiscale modeling of tunnel fires with this new feature in FDS. The two sub-models were coupled directly. The results were...... compared with reference works on multiscale modeling and the outcome is considered positive, with a deviation of less than 5% in magnitude of relevant parameters, yet with a significant reduction of the simulation runtime. As such, the multiscale method is deemed feasible for simulating tunnel fires in FDS......6. However, the simplifications that are made in this work require further investigation in order to take full advantage of the potential of this computational method. INTRODUCTION Multiscale modeling for tunnel flows and fires has previously been studied using RANS general purpose CFD software...

  11. Multifunctional Collaborative Modeling and Analysis Methods in Engineering Science

    Science.gov (United States)

    Ransom, Jonathan B.; Broduer, Steve (Technical Monitor)

    2001-01-01

    Engineers are challenged to produce better designs in less time and for less cost. Hence, to investigate novel and revolutionary design concepts, accurate, high-fidelity results must be assimilated rapidly into the design, analysis, and simulation process. This assimilation should consider diverse mathematical modeling and multi-discipline interactions necessitated by concepts exploiting advanced materials and structures. Integrated high-fidelity methods with diverse engineering applications provide the enabling technologies to assimilate these high-fidelity, multi-disciplinary results rapidly at an early stage in the design. These integrated methods must be multifunctional, collaborative, and applicable to the general field of engineering science and mechanics. Multifunctional methodologies and analysis procedures are formulated for interfacing diverse subdomain idealizations including multi-fidelity modeling methods and multi-discipline analysis methods. These methods, based on the method of weighted residuals, ensure accurate compatibility of primary and secondary variables across the subdomain interfaces. Methods are developed using diverse mathematical modeling (i.e., finite difference and finite element methods) and multi-fidelity modeling among the subdomains. Several benchmark scalar-field and vector-field problems in engineering science are presented with extensions to multidisciplinary problems. Results for all problems presented are in overall good agreement with the exact analytical solution or the reference numerical solution. Based on the results, the integrated modeling approach using the finite element method for multi-fidelity discretization among the subdomains is identified as most robust. The multiple-method approach is advantageous when interfacing diverse disciplines in which each of the method's strengths are utilized. The multifunctional methodology presented provides an effective mechanism by which domains with diverse idealizations are

  12. Wildland fire emissions, carbon, and climate: Modeling fuel consumption

    Science.gov (United States)

    Roger D. Ottmar

    2014-01-01

    Fuel consumption specifies the amount of vegetative biomass consumed during wildland fire. It is a two-stage process of pyrolysis and combustion that occurs simultaneously and at different rates depending on the characteristics and condition of the fuel, weather, topography, and in the case of prescribed fire, ignition rate and pattern. Fuel consumption is the basic...

  13. Influence of daily versus monthly fire emissions on atmospheric model applications in the tropics

    Science.gov (United States)

    Marlier, M. E.; Voulgarakis, A.; Faluvegi, G.; Shindell, D. T.; DeFries, R. S.

    2012-12-01

    Fires are widely used throughout the tropics to create and maintain areas for agriculture, but are also significant contributors to atmospheric trace gas and aerosol concentrations. However, the timing and magnitude of fire activity can vary strongly by year and ecosystem type. For example, frequent, low intensity fires dominate in African savannas whereas Southeast Asian peatland forests are susceptible to huge pulses of emissions during regional El Niño droughts. Despite the potential implications for modeling interactions with atmospheric chemistry and transport, fire emissions have commonly been input into global models at a monthly resolution. Recognizing the uncertainty that this can introduce, several datasets have parsed fire emissions to daily and sub-daily scales with satellite active fire detections. In this study, we explore differences between utilizing the monthly and daily Global Fire Emissions Database version 3 (GFED3) products as inputs into the NASA GISS-E2 composition climate model. We aim to understand how the choice of the temporal resolution of fire emissions affects uncertainty with respect to several common applications of global models: atmospheric chemistry, air quality, and climate. Focusing our analysis on tropical ozone, carbon monoxide, and aerosols, we compare modeled concentrations with available ground and satellite observations. We find that increasing the temporal frequency of fire emissions from monthly to daily can improve correlations with observations, predominately in areas or during seasons more heavily affected by fires. Differences between the two datasets are more evident with public health applications: daily resolution fire emissions increases the number of days exceeding World Health Organization air quality targets.

  14. Staying Connected: Sustaining Collaborative Care Models with Limited Funding.

    Science.gov (United States)

    Johnston, Brenda J; Peppard, Lora; Newton, Marian

    2015-08-01

    Providing psychiatric services in the primary care setting is challenging. The multidisciplinary, coordinated approach of collaborative care models (CCMs) addresses these challenges. The purpose of the current article is to discuss the implementation of a CCM at a free medical clinic (FMC) where volunteer staff provide the majority of services. Essential components of CCMs include (a) comprehensive screening and assessment, (b) shared development and communication of care plans among providers and the patient, and (c) care coordination and management. Challenges to implementing and sustaining a CCM at a FMC in Virginia attempting to meet the medical and psychiatric needs of the underserved are addressed. Although the CCM produced favorable outcomes, sustaining the model long-term presented many challenges. Strategies for addressing these challenges are discussed. Copyright 2015, SLACK Incorporated.

  15. Simulation of a Large Wildfire in a Coupled Fire-Atmosphere Model

    Directory of Open Access Journals (Sweden)

    Jean-Baptiste Filippi

    2018-06-01

    Full Text Available The Aullene fire devastated more than 3000 ha of Mediterranean maquis and pine forest in July 2009. The simulation of combustion processes, as well as atmospheric dynamics represents a challenge for such scenarios because of the various involved scales, from the scale of the individual flames to the larger regional scale. A coupled approach between the Meso-NH (Meso-scale Non-Hydrostatic atmospheric model running in LES (Large Eddy Simulation mode and the ForeFire fire spread model is proposed for predicting fine- to large-scale effects of this extreme wildfire, showing that such simulation is possible in a reasonable time using current supercomputers. The coupling involves the surface wind to drive the fire, while heat from combustion and water vapor fluxes are injected into the atmosphere at each atmospheric time step. To be representative of the phenomenon, a sub-meter resolution was used for the simulation of the fire front, while atmospheric simulations were performed with nested grids from 2400-m to 50-m resolution. Simulations were run with or without feedback from the fire to the atmospheric model, or without coupling from the atmosphere to the fire. In the two-way mode, the burnt area was reproduced with a good degree of realism at the local scale, where an acceleration in the valley wind and over sloping terrain pushed the fire line to locations in accordance with fire passing point observations. At the regional scale, the simulated fire plume compares well with the satellite image. The study explores the strong fire-atmosphere interactions leading to intense convective updrafts extending above the boundary layer, significant downdrafts behind the fire line in the upper plume, and horizontal wind speeds feeding strong inflow into the base of the convective updrafts. The fire-induced dynamics is induced by strong near-surface sensible heat fluxes reaching maximum values of 240 kW m − 2 . The dynamical production of turbulent kinetic

  16. A model and typology of collaboration between professionals in healthcare organizations.

    Science.gov (United States)

    D'Amour, Danielle; Goulet, Lise; Labadie, Jean-François; Martín-Rodriguez, Leticia San; Pineault, Raynald

    2008-09-21

    The new forms of organization of healthcare services entail the development of new clinical practices that are grounded in collaboration. Despite recent advances in research on the subject of collaboration, there is still a need for a better understanding of collaborative processes and for conceptual tools to help healthcare professionals develop collaboration amongst themselves in complex systems. This study draws on D'Amour's structuration model of collaboration to analyze healthcare facilities offering perinatal services in four health regions in the province of Quebec. The objectives are to: 1) validate the indicators of the structuration model of collaboration; 2) evaluate interprofessional and interorganizational collaboration in four health regions; and 3) propose a typology of collaboration A multiple-case research strategy was used. The cases were the healthcare facilities that offer perinatal services in four health regions in the province of Quebec (Canada). The data were collected through 33 semi-structured interviews with healthcare managers and professionals working in the four regions. Written material was also analyzed. The data were subjected to a "mixed" inductive-deductive analysis conducted in two main stages: an internal analysis of each case followed by a cross-sectional analysis of all the cases. The collaboration indicators were shown to be valid, although some changes were made to three of them. Analysis of the data showed great variation in the level of collaboration between the cases and on each dimension. The results suggest a three-level typology of collaboration based on the ten indicators: active collaboration, developing collaboration and potential collaboration. The model and the typology make it possible to analyze collaboration and identify areas for improvement. Researchers can use the indicators to determine the intensity of collaboration and link it to clinical outcomes. Professionals and administrators can use the model to

  17. Modeling fire spatial non-stationary in Portugal using GWR and GAMLSS

    Science.gov (United States)

    Sá, Ana C. L.; Amaral Turkman, Maria A.; Bistinas, Ioannis; Pereira, José M. C.

    2014-05-01

    Portuguese wildfires are responsible for large environmental, ecological and socio-economic impacts and, in the last decade, vegetation fires consumed on average 140.000ha/year. Portugal has a unique fires-atlas of burnt scar perimeters covering the 1975-2009 period, which allows the assessment of the fire most affected areas. It's crucial to understand the influence of the main drivers of forest fires and its spatial distribution in order to set new management strategies to reduce its impacts. Thus, this study aims at evaluating the spatial stationarity of the fire-environment relationship using two statistical approaches: Geographically Weighted Regression (GWR) and Generalized Additive Models for Location, Scale and Shape (GAMLSS). Analysis was performed using a regular 2kmx2km cell size grid, a total of 21293 observations overlaying the mainland of Portugal. Fire incidence was determined as the number of times each grid cell burned in the 35 years period. For the GWR analysis the group of environmental variables selected as predictors are: ignition source (population density (PD)); vegetation (proportion of forest and shrubland (FORSHR)); and weather (total precipitation of the coldest quarter (PCQ). Results showed that the fire-environment relationship is non-stationary, thus the coefficient estimates of all the predictors vary spatially, both in magnitude and sign. The most statistically significant predictor is FORSHR, followed by the PCQ. Despite the relationship between fire incidence and PD is non-stationary, only 9% of the observations are statistically significant at a 95% level of confidence. When compared with the Ordinary Least Squares (OLS) global model, 53% of the R2 statistic is above the 26% global estimated value, meaning a better explanation of the fire incidence variance with the local model approach. Using the same environmental variables, fire incidence was also modeled using GAMLSS to characterize nonstationarities in fire incidence. It is

  18. Fuel treatment effects on modeled landscape level fire behavior in the northern Sierra Nevada

    Science.gov (United States)

    J.J. Moghaddas; B.M. Collins; K. Menning; E.E.Y. Moghaddas; S.L. Stephens

    2010-01-01

    Across the western United States, decades of fire exclusion combined with past management history have contributed to the current condition of extensive areas of high-density, shade-tolerant coniferous stands that are increasingly prone to high-severity fires. Here, we report the modeled effects of constructed defensible fuel profile zones and group selection...

  19. Modeling wildland fire containment with uncertain flame length and fireline width

    Science.gov (United States)

    Romain Mees; David Strauss; Richard Chase

    1993-01-01

    We describe a mathematical model for the probability that a fireline succeeds in containing a fire. The probability increases as the fireline width increases, and also as the fire's flame length decreases. More interestingly, uncertainties in width and flame length affect the computed containment probabilities, and can thus indirectly affect the optimum allocation...

  20. Advancing investigation and physical modeling of first-order fire effects on soils

    Science.gov (United States)

    William J. Massman; John M. Frank; Sacha J. Mooney

    2010-01-01

    Heating soil during intense wildland fires or slash-pile burns can alter the soil irreversibly, resulting in many significant long-term biological, chemical, physical, and hydrological effects. To better understand these long-term effects, it is necessary to improve modeling capability and prediction of the more immediate, or first-order, effects that fire can have on...

  1. Using Modeling and Rehearsal to Teach Fire Safety to Children with Autism

    Science.gov (United States)

    Garcia, David; Dukes, Charles; Brady, Michael P.; Scott, Jack; Wilson, Cynthia L.

    2016-01-01

    We evaluated the efficacy of an instructional procedure to teach young children with autism to evacuate settings and notify an adult during a fire alarm. A multiple baseline design across children showed that an intervention that included modeling, rehearsal, and praise was effective in teaching fire safety skills. Safety skills generalized to…

  2. First-order fire effects on herbs and Shrubs: present knowledge and process modeling needs

    Science.gov (United States)

    Kirsten Stephan; Melanie Miller; Matthew B. Dickinson

    2010-01-01

    Herbaceous plants and shrubs have received little attention in terms of fire effects modeling despite their critical role in ecosystem integrity and resilience after wildfires and prescribed burns. In this paper, we summarize current knowledge of direct effects of fire on herb and shrub (including cacti) vegetative tissues and seed banks, propose key components for...

  3. Evaluating the coupled vegetation-fire model, LPJ-GUESS-SPITFIRE, against observed tropical forest biomass

    Science.gov (United States)

    Spessa, Allan; Forrest, Matthew; Werner, Christian; Steinkamp, Joerg; Hickler, Thomas

    2013-04-01

    Wildfire is a fundamental Earth System process. It is the most important disturbance worldwide in terms of area and variety of biomes affected; a major mechanism by which carbon is transferred from the land to the atmosphere (2-4 Pg per annum, equiv. 20-30% of global fossil fuel emissions over the last decade); and globally a significant source of particulate aerosols and trace greenhouse gases. Fire is also potentially important as a feedback in the climate system. If climate change favours more intense fire regimes, this would result in a net transfer of carbon from ecosystems to the atmosphere, as well as higher emissions, and under certain circumstances, increased troposphere ozone production- all contributing to positive climate-land surface feedbacks. Quantitative analysis of fire-vegetation-climate interactions has been held back until recently by a lack of consistent global data sets on fire, and by the underdeveloped state of dynamic vegetation-fire modelling. Dynamic vegetation-fire modelling is an essential part of our forecasting armory for examining the possible impacts of climate, fire regimes and land-use on ecosystems and emissions from biomass burning beyond the observation period, as part of future climate or paleo-climate studies. LPJ-GUESS is a process-based model of vegetation dynamics designed for regional to global applications. It combines features of the Lund-Potsdam-Jena Dynamic Global Vegetation Model (LPJ-DGVM) with those of the General Ecosystem Simulator (GUESS) in a single, flexible modelling framework. The models have identical representations of eco-physiological and biogeochemical processes, including the hydrological cycle. However, they differ in the detail with which vegetation dynamics and canopy structure are simulated. Simplified, computationally efficient representations are used in the LPJ-DGVM, while LPJ-GUESS employs a gap-model approach, which better captures ecological succession and hence ecosystem changes due to

  4. Modeling fires in adjacent ship compartments with computational fluid dynamics

    International Nuclear Information System (INIS)

    Wix, S.D.; Cole, J.K.; Koski, J.A.

    1998-01-01

    This paper presents an analysis of the thermal effects on radioactive (RAM) transportation pack ages with a fire in an adjacent compartment. An assumption for this analysis is that the adjacent hold fire is some sort of engine room fire. Computational fluid dynamics (CFD) analysis tools were used to perform the analysis in order to include convective heat transfer effects. The analysis results were compared to experimental data gathered in a series of tests on the United States Coast Guard ship Mayo Lykes located at Mobile, Alabama. (authors)

  5. Business models for horizontal collaboration : a practical case study with reusable crates

    NARCIS (Netherlands)

    Brandi, Teresa

    2012-01-01

    This project is centered in the topic of horizontal collaboration. The first part focuses on finding business models for horizontal collaboration. The second part is a practical case study at Kuehne + Nagel. Horizontal collaboration consists of two or more independent companies that plan and execute

  6. Enhancing adaptive capacity for restoring fire-dependent ecosystems: the Fire Learning Network's Prescribed Fire Training Exchanges

    Directory of Open Access Journals (Sweden)

    Andrew G. Spencer

    2015-09-01

    Full Text Available Prescribed fire is a critical tool for promoting restoration and increasing resilience in fire-adapted ecosystems, but there are barriers to its use, including a shortage of personnel with adequate ecological knowledge and operational expertise to implement prescribed fire across multijurisdictional landscapes. In the United States, recognized needs for both professional development and increased use of fire are not being met, often because of institutional limitations. The Fire Learning Network has been characterized as a multiscalar, collaborative network that works to enhance the adaptive capacity of fire management institutions, and this network developed the Prescribed Fire Training Exchanges (TREXs to address persistent challenges in increasing the capacity for prescribed fire implementation. Our research was designed to investigate where fire professionals face professional barriers, how the TREX addresses these, and in what ways the TREX may be contributing to the adaptive capacity of fire management institutions. We evaluated the training model using surveys, interviews, focus groups, and participant observation. We found that, although the training events cannot overcome all institutional barriers, they incorporate the key components of professional development in fire; foster collaboration, learning, and network building; and provide flexible opportunities with an emphasis on local context to train a variety of professionals with disparate needs. The strategy also offers an avenue for overcoming barriers faced by contingent and nonfederal fire professionals in attaining training and operational experience, thereby increasing the variety of actors and resources involved in fire management. Although it is an incremental step, the TREX is contributing to the adaptive capacity of institutions in social-ecological systems in which fire is a critical ecological process.

  7. Enabling Cross-Discipline Collaboration Via a Functional Data Model

    Science.gov (United States)

    Lindholm, D. M.; Wilson, A.; Baltzer, T.

    2016-12-01

    Many research disciplines have very specialized data models that are used to express the detailed semantics that are meaningful to that community and easily utilized by their data analysis tools. While invaluable to members of that community, such expressive data structures and metadata are of little value to potential collaborators from other scientific disciplines. Many data interoperability efforts focus on the difficult task of computationally mapping concepts from one domain to another to facilitate discovery and use of data. Although these efforts are important and promising, we have found that a great deal of discovery and dataset understanding still happens at the level of less formal, personal communication. However, a significant barrier to inter-disciplinary data sharing that remains is one of data access.Scientists and data analysts continue to spend inordinate amounts of time simply trying to get data into their analysis tools. Providing data in a standard file format is often not sufficient since data can be structured in many ways. Adhering to more explicit community standards for data structure and metadata does little to help those in other communities.The Functional Data Model specializes the Relational Data Model (used by many database systems)by defining relations as functions between independent (domain) and dependent (codomain) variables. Given that arrays of data in many scientific data formats generally represent functionally related parameters (e.g. temperature as a function of space and time), the Functional Data Model is quite relevant for these datasets as well. The LaTiS software framework implements the Functional Data Model and provides a mechanism to expose an existing data source as a LaTiS dataset. LaTiS datasets can be manipulated using a Functional Algebra and output in any number of formats.LASP has successfully used the Functional Data Model and its implementation in the LaTiS software framework to bridge the gap between

  8. A stochastic Forest Fire Model for future land cover scenarios assessment

    Directory of Open Access Journals (Sweden)

    M. D'Andrea

    2010-10-01

    Full Text Available Land cover is affected by many factors including economic development, climate and natural disturbances such as wildfires. The ability to evaluate how fire regimes may alter future vegetation, and how future vegetation may alter fire regimes, would assist forest managers in planning management actions to be carried out in the face of anticipated socio-economic and climatic change. In this paper, we present a method for calibrating a cellular automata wildfire regime simulation model with actual data on land cover and wildfire size-frequency. The method is based on the observation that many forest fire regimes, in different forest types and regions, exhibit power law frequency-area distributions. The standard Drossel-Schwabl cellular automata Forest Fire Model (DS-FFM produces simulations which reproduce this observed pattern. However, the standard model is simplistic in that it considers land cover to be binary – each cell either contains a tree or it is empty – and the model overestimates the frequency of large fires relative to actual landscapes. Our new model, the Modified Forest Fire Model (MFFM, addresses this limitation by incorporating information on actual land use and differentiating among various types of flammable vegetation. The MFFM simulation model was tested on forest types with Mediterranean and sub-tropical fire regimes. The results showed that the MFFM was able to reproduce structural fire regime parameters for these two regions. Further, the model was used to forecast future land cover. Future research will extend this model to refine the forecasts of future land cover and fire regime scenarios under climate, land use and socio-economic change.

  9. Catchment-scale Validation of a Physically-based, Post-fire Runoff and Erosion Model

    Science.gov (United States)

    Quinn, D.; Brooks, E. S.; Robichaud, P. R.; Dobre, M.; Brown, R. E.; Wagenbrenner, J.

    2017-12-01

    The cascading consequences of fire-induced ecological changes have profound impacts on both natural and managed forest ecosystems. Forest managers tasked with implementing post-fire mitigation strategies need robust tools to evaluate the effectiveness of their decisions, particularly those affecting hydrological recovery. Various hillslope-scale interfaces of the physically-based Water Erosion Prediction Project (WEPP) model have been successfully validated for this purpose using fire-effected plot experiments, however these interfaces are explicitly designed to simulate single hillslopes. Spatially-distributed, catchment-scale WEPP interfaces have been developed over the past decade, however none have been validated for post-fire simulations, posing a barrier to adoption for forest managers. In this validation study, we compare WEPP simulations with pre- and post-fire hydrological records for three forested catchments (W. Willow, N. Thomas, and S. Thomas) that burned in the 2011 Wallow Fire in Northeastern Arizona, USA. Simulations were conducted using two approaches; the first using automatically created inputs from an online, spatial, post-fire WEPP interface, and the second using manually created inputs which incorporate the spatial variability of fire effects observed in the field. Both approaches were compared to five years of observed post-fire sediment and flow data to assess goodness of fit.

  10. Microclimate and Modeled Fire Behavior Differ Between Adjacent Forest Types in Northern Portugal

    Directory of Open Access Journals (Sweden)

    Anita Pinto

    2014-10-01

    Full Text Available Fire severity varies with forest composition and structure, reflecting micrometeorology and the fuel complex, but their respective influences are difficult to untangle from observation alone. We quantify the differences in fire weather between different forest types and the resulting differences in modeled fire behavior. Collection of in-stand weather data proceeded during two summer periods in three adjacent stands in northern Portugal, respectively Pinus pinaster (PP, Betula alba (BA, and Chamaecyparis lawsoniana (CL. Air temperature, relative humidity and wind speed varied respectively as CL < PP < BA, PP < CL < BA, and CL < BA < PP. Differences between PP and the other types were greatest during the warmest and driest hours of the day in a sequence of 10 days with high fire danger. Estimates of daytime moisture content of fine dead fuels and fire behavior characteristics for this period, respectively, from Behave and BehavePlus, indicate a CL < BA < PP gradient in fire potential. High stand density in CL and BA ensured lower wind speed and higher fuel moisture content than in PP, limiting the likelihood of an extreme fire environment. However, regression tree analysis revealed that the fire behavior distinction between the three forest types was primarily a function of the surface fuel complex, and more so during extreme fire weather conditions.

  11. Modelling initial mortality of Abies religiosa in a crown fire in Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Temiño-Villota, S.; Rodríguez-Trejo, D.A.; Molina Terrén, D.M.; Ryan, K.

    2016-07-01

    Aim of the study: The objectives of this work were to determine which morphological and fire severity variables may help explain the mortality of adult Abies religiosa (Kunth) Schltdl. & Cham., to model the probability of this species after being affected by crown fire, and to obtain more elements to classify the sacred fir in terms of fire resistance. This type of studies are relevant to estimate the impact of crown fires on the climax forests that forms this species. Area of study: The burned forest was located in the southern Mexico City, borough. Material and methods: Morphological variables and fire severity indicators were collected for 335 Abies religiosa trees burned by a mixed severity fire. Logistic regression was used to analyze data and develop models that best explained tree mortality. Main results: Survival was 26.9%. The models for height (p≤0.0001), diameter at breast height (p=0.0082), crown length (p≤0.0001) and crown base height (p≤0.0001) were significant, with a negative relationship between each one of these variables and probability of mortality. The significant severity variables were lethal scorch height (p≤0.0001) and crown kill (p≤ 0.0001), which have a direct relationship with probability of mortality. Highlights: This species is moderately fire-resistant. Crown kill ≥ 70% markedly increases mortality. Silvicultural activities such as pruning, thinning and fuel management can reduce the risk of crown fires. (Author)

  12. Modelling initial mortality of Abies religiosa in a crown fire in Mexico

    Directory of Open Access Journals (Sweden)

    Salomé Temiño-Villota

    2016-04-01

    Full Text Available Aim of study: The objectives of this work were to determine which morphological and fire severity variables may help explain the mortality of adult Abies religiosa (Kunth Schltdl. & Cham., to model the probability of this species after being affected by crown fire, and to obtain more elements to classify the sacred fir in terms of fire resistance. This type of studies are relevant to estimate the impact of crown fires on the climax forests that forms this species.Area of study: The burned forest was located in the southern Mexico City, borough.Material and methods: Morphological variables and fire severity indicators were collected for 335 Abies religiosa trees burned by a mixed severity fire. Logistic regression was used to analyze data and develop models that best explained tree mortality.Main results: Survival was 26.9%. The models for height (p≤0.0001, diameter at breast height (p=0.0082, crown length (p≤0.0001 and crown base height (p≤0.0001 were significant, with a negative relationship between each one of these variables and probability of mortality. The significant severity variables were lethal scorch height (p≤0.0001 and crown kill (p≤ 0.0001, which have a direct relationship with probability of mortality.Highlights: This species is moderately fire-resistant. Crown kill ≥ 70% markedly increases mortality. Silvicultural activities such as pruning, thinning and fuel management can reduce the risk of crown fires.

  13. Satellite, climatological, and theoretical inputs for modeling of the diurnal cycle of fire emissions

    Science.gov (United States)

    Hyer, E. J.; Reid, J. S.; Schmidt, C. C.; Giglio, L.; Prins, E.

    2009-12-01

    The diurnal cycle of fire activity is crucial for accurate simulation of atmospheric effects of fire emissions, especially at finer spatial and temporal scales. Estimating diurnal variability in emissions is also a critical problem for construction of emissions estimates from multiple sensors with variable coverage patterns. An optimal diurnal emissions estimate will use as much information as possible from satellite fire observations, compensate known biases in those observations, and use detailed theoretical models of the diurnal cycle to fill in missing information. As part of ongoing improvements to the Fire Location and Monitoring of Burning Emissions (FLAMBE) fire monitoring system, we evaluated several different methods of integrating observations with different temporal sampling. We used geostationary fire detections from WF_ABBA, fire detection data from MODIS, empirical diurnal cycles from TRMM, and simple theoretical diurnal curves based on surface heating. Our experiments integrated these data in different combinations to estimate the diurnal cycles of emissions for each location and time. Hourly emissions estimates derived using these methods were tested using an aerosol transport model. We present results of this comparison, and discuss the implications of our results for the broader problem of multi-sensor data fusion in fire emissions modeling.

  14. A Design of Product Collaborative Online Configuration Model

    Science.gov (United States)

    Wang, Xiaoguo; Zheng, Jin; Zeng, Qian

    According to the actual needs of mass customization, the personalization of product and its collaborative design, the paper analyzes and studies the working mechanism of modular-based product configuration technology and puts forward an information model of modular product family. Combined with case-based reasoning techniques (CBR) and the constraint satisfaction problem solving techniques (CSP), we design and study the algorithm for product configuration, and analyze its time complexity. A car chassis is made as the application object, we provide a prototype system of online configuration. Taking advantage of this system, designers can make appropriate changes on the existing programs in accordance with the demand. This will accelerate all aspects of product development and shorten the product cycle. Also the system will provide a strong technical support for enterprises to improve their market competitiveness.

  15. An enhanced fire hazard assessment model and validation experiments for vertical cable trays

    International Nuclear Information System (INIS)

    Li, Lu; Huang, Xianjia; Bi, Kun; Liu, Xiaoshuang

    2016-01-01

    Highlights: • An enhanced model was developed for vertical cable fire hazard assessment in NPP. • The validated experiments on vertical cable tray fires were conducted. • The capability of the model for cable tray with different cable spacing were tested. - Abstract: The model, referred to as FLASH-CAT (Flame Spread over Horizontal Cable Trays), was developed to estimate the heat release rate for vertical cable tray fire. The focus of this work is to investigate the application of an enhanced model to the single vertical cable tray fires with different cable spacing. The experiments on vertical cable tray fires with three typical cable spacing were conducted. The histories of mass loss rate and flame length were recorded during the cable fire. From the experimental results, it is found that the space between cable lines intensifies the cable combustion and accelerates the flame spread. The predictions by the enhanced model show good agreements with the experimental data. At the same time, it is shown that the enhanced model is capable of predicting the different behaviors of cable fires with different cable spacing by adjusting the flame spread speed only.

  16. An enhanced fire hazard assessment model and validation experiments for vertical cable trays

    Energy Technology Data Exchange (ETDEWEB)

    Li, Lu [Sate Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230027 (China); Huang, Xianjia, E-mail: huangxianjia@gziit.ac.cn [Joint Laboratory of Fire Safety in Nuclear Power Plants, Institute of Industry Technology Guangzhou & Chinese Academy of Sciences, Guangzhou 511458 (China); Bi, Kun; Liu, Xiaoshuang [China Nuclear Power Design Co., Ltd., Shenzhen 518045 (China)

    2016-05-15

    Highlights: • An enhanced model was developed for vertical cable fire hazard assessment in NPP. • The validated experiments on vertical cable tray fires were conducted. • The capability of the model for cable tray with different cable spacing were tested. - Abstract: The model, referred to as FLASH-CAT (Flame Spread over Horizontal Cable Trays), was developed to estimate the heat release rate for vertical cable tray fire. The focus of this work is to investigate the application of an enhanced model to the single vertical cable tray fires with different cable spacing. The experiments on vertical cable tray fires with three typical cable spacing were conducted. The histories of mass loss rate and flame length were recorded during the cable fire. From the experimental results, it is found that the space between cable lines intensifies the cable combustion and accelerates the flame spread. The predictions by the enhanced model show good agreements with the experimental data. At the same time, it is shown that the enhanced model is capable of predicting the different behaviors of cable fires with different cable spacing by adjusting the flame spread speed only.

  17. A combustion model of vegetation burning in "Tiger" fire propagation tool

    Science.gov (United States)

    Giannino, F.; Ascoli, D.; Sirignano, M.; Mazzoleni, S.; Russo, L.; Rego, F.

    2017-11-01

    In this paper, we propose a semi-physical model for the burning of vegetation in a wildland fire. The main physical-chemical processes involved in fire spreading are modelled through a set of ordinary differential equations, which describe the combustion process as linearly related to the consumption of fuel. The water evaporation process from leaves and wood is also considered. Mass and energy balance equations are written for fuel (leaves and wood) assuming that combustion process is homogeneous in space. The model is developed with the final aim of simulating large-scale wildland fires which spread on heterogeneous landscape while keeping the computation cost very low.

  18. The Design of a Fire Source in Scale-Model Experiments with Smoke Ventilation

    DEFF Research Database (Denmark)

    Nielsen, Peter Vilhelm; Brohus, Henrik; la Cour-Harbo, H.

    2004-01-01

    The paper describes the design of a fire and a smoke source for scale-model experiments with smoke ventilation. It is only possible to work with scale-model experiments where the Reynolds number is reduced compared to full scale, and it is demonstrated that special attention to the fire source...... (heat and smoke source) may improve the possibility of obtaining Reynolds number independent solutions with a fully developed flow. The paper shows scale-model experiments for the Ofenegg tunnel case. Design of a fire source for experiments with smoke ventilation in a large room and smoke movement...

  19. Modeling the Emission of CO from Wood Fires using Detailed Chemical Kinetics

    DEFF Research Database (Denmark)

    Dederichs, Anne

    Carbon monoxide is treated as one of the most common and dangerous of gases evolving in fires. Modeling the formation of the toxic gas CO from in fire enclosures using detailed chemical kinetics is the topic of this manuscript. A semi-empirical model is developed to study the formation of CO from......, the model separately treats the process of pyrolysis and combustion. For under ventilated conditions and at high temperatures during pyrolysis it is found that the process of pyrolysation strongly influences the formation of CO in fire. CO2 follows the same trend....

  20. The Answering Process for Multiple-Choice Questions in Collaborative Learning: A Mathematical Learning Model Analysis

    Science.gov (United States)

    Nakamura, Yasuyuki; Nishi, Shinnosuke; Muramatsu, Yuta; Yasutake, Koichi; Yamakawa, Osamu; Tagawa, Takahiro

    2014-01-01

    In this paper, we introduce a mathematical model for collaborative learning and the answering process for multiple-choice questions. The collaborative learning model is inspired by the Ising spin model and the model for answering multiple-choice questions is based on their difficulty level. An intensive simulation study predicts the possibility of…

  1. Tool Support for Collaborative Teaching and Learning of Object-Oriented Modelling

    DEFF Research Database (Denmark)

    Hansen, Klaus Marius; Ratzer, Anne Vinter

    2002-01-01

    Modeling is central to doing and learning object-oriented development. We present a new tool, Ideogramic UML, for gesture-based collaborative modeling with the Unified Modeling Language (UML), which can be used to collaboratively teach and learn modeling. Furthermore, we discuss how we have...

  2. Exploring the Impact of Students' Learning Approach on Collaborative Group Modeling of Blood Circulation

    Science.gov (United States)

    Lee, Shinyoung; Kang, Eunhee; Kim, Heui-Baik

    2015-01-01

    This study aimed to explore the effect on group dynamics of statements associated with deep learning approaches (DLA) and their contribution to cognitive collaboration and model development during group modeling of blood circulation. A group was selected for an in-depth analysis of collaborative group modeling. This group constructed a model in a…

  3. An Approach for Maintaining Models of an E-Commerce Collaboration

    NARCIS (Netherlands)

    Bodenstaff, L.; Wombacher, Andreas; Reichert, M.U.; Wieringa, Roelf J.

    To keep an overview on complex E-Commerce collaborations several models are used to describe them. When models overlap in describing a collaboration, the overlapping information should not contradict. Models are of different nature and maintained by different people. Therefore, keeping model-overlap

  4. An Approach for Maintaining Models of an E-Commerce Collaboration

    NARCIS (Netherlands)

    Bodenstaff, L.; Wombacher, Andreas; Reichert, M.U.; Wieringa, Roelf J.

    To keep an overview on complex E-Commerce collaborations several models are used to describe them. When models overlap in describing a collaboration, the overlapping information should not contradict. Models are of different nature and maintained by different people. Therefore, keeping model-overlap

  5. Modeling syngas-fired gas turbine engines with two dilutants

    Science.gov (United States)

    Hawk, Mitchell E.

    2011-12-01

    Prior gas turbine engine modeling work at the University of Wyoming studied cycle performance and turbine design with air and CO2-diluted GTE cycles fired with methane and syngas fuels. Two of the cycles examined were unconventional and innovative. The work presented herein reexamines prior results and expands the modeling by including the impacts of turbine cooling and CO2 sequestration on GTE cycle performance. The simple, conventional regeneration and two alternative regeneration cycle configurations were examined. In contrast to air dilution, CO2 -diluted cycle efficiencies increased by approximately 1.0 percentage point for the three regeneration configurations examined, while the efficiency of the CO2-diluted simple cycle decreased by approximately 5.0 percentage points. For CO2-diluted cycles with a closed-exhaust recycling path, an optimum CO2-recycle pressure was determined for each configuration that was significantly lower than atmospheric pressure. Un-cooled alternative regeneration configurations with CO2 recycling achieved efficiencies near 50%, which was approximately 3.0 percentage points higher than the conventional regeneration cycle and simple cycle configurations that utilized CO2 recycling. Accounting for cooling of the first two turbine stages resulted in a 2--3 percentage point reduction in un-cooled efficiency, with air dilution corresponding to the upper extreme. Additionally, when the work required to sequester CO2 was accounted for, cooled cycle efficiency decreased by 4--6 percentage points, and was more negatively impacted when syngas fuels were used. Finally, turbine design models showed that turbine blades are shorter with CO2 dilution, resulting in fewer design restrictions.

  6. PyrE, an interactive fire module within the NASA-GISS Earth System Model

    Science.gov (United States)

    Mezuman, K.; Bauer, S. E.; Tsigaridis, K.

    2017-12-01

    Fires directly affect the composition of the atmosphere and Earth's radiation balance by emitting a suite of reactive gases and particles. Having an interactive fire module in an Earth System Model allows us to study the natural and anthropogenic drivers, feedbacks, and interactions of biomass burning in different time periods. To do so we have developed PyrE, the NASA-GISS interactive fire emissions model. PyrE uses the flammability, ignition, and suppression parameterization proposed by Pechony and Shindell (2009), and is coupled to a burned area and surface recovery parameterization. The burned area calculation follows CLM's approach (Li et al., 2012), paired with an offline recovery scheme based on Ent's Terrestrial Biosphere Model (Ent TBM) carbon pool turnover time. PyrE is driven by environmental variables calculated by climate simulations, population density data, MODIS fire counts and LAI retrievals, as well as GFED4s emissions. Since the model development required extensive use of reference datasets, in addition to comparing it to GFED4s BA, we evaluate it by studying the effect of fires on atmospheric composition and climate. Our results show good agreement globally, with some regional differences. Finally, we quantify the present day fire radiative forcing. The development of PyrE allowed us for the first time to interactively simulate climate and fire activity with GISS-ModelE3

  7. Fire spread in chaparral – a comparison of laboratory data and model predictions in burning live fuels

    Science.gov (United States)

    David R. Weise; Eunmo Koo; Xiangyang Zhou; Shankar Mahalingam; Frédéric Morandini; Jacques-Henri Balbi

    2016-01-01

    Fire behaviour data from 240 laboratory fires in high-density live chaparral fuel beds were compared with model predictions. Logistic regression was used to develop a model to predict fire spread success in the fuel beds and linear regression was used to predict rate of spread. Predictions from the Rothermel equation and three proposed changes as well as two physically...

  8. Collaborative Visualization for Large-Scale Accelerator Electromagnetic Modeling

    International Nuclear Information System (INIS)

    2010-01-01

    In the Phase I SBIR we proposed a ParaView-based solution to provide an environment for individuals to actively collaborate in the visualization process. The technical objectives of Phase I were: (1) to determine the set of features required for an effect collaborative system; (2) to implement a two-person collaborative prototype; and (3) to implement key collaborative features such as control locking and annotation. Accordingly, we implemented a ParaView-based collaboration prototype with support for collaborating with up to four simultaneous clients. We also implemented collaborative features such as control locking, chatting, annotation etc. Due to in part of the flexibility provided by the ParaView framework and the design features implemented in the prototype, we were able to support collaboration with multiple views, instead of a simple give as initially proposed in Phase I. In this section we will summarize the results we obtained during the Phase I project. ParaView is complex, scalable, client-server application framework built on top of the VTK visualization engine. During the implementation of the Phase I prototype, we realized that the ParaView framework naturally supports collaboration technology; hence we were able to go beyond the proposed Phase I prototype in several ways. For example, we were able to support for multiple views, enable server-as well as client-side rendering, and manage up to four heterogeneous clients. The success we achieved with Phase I clearly demonstrated the technical feasibility of the ParaView based collaborative framework we are proposing in the Phase II effort. We also investigated using the web browser as one of the means of participating in a collaborative session. This would enable non-visualization experts to participate in the collaboration process without being intimidated by a complex application such as ParaView. Hence we also developed a prototype web visualization applet that makes it possible for interactive

  9. Collaborative Visualization for Large-Scale Accelerator Electromagnetic Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Schussman, Greg; /SLAC

    2010-08-25

    In the Phase I SBIR we proposed a ParaView-based solution to provide an environment for individuals to actively collaborate in the visualization process. The technical objectives of Phase I were: (1) to determine the set of features required for an effect collaborative system; (2) to implement a two-person collaborative prototype; and (3) to implement key collaborative features such as control locking and annotation. Accordingly, we implemented a ParaView-based collaboration prototype with support for collaborating with up to four simultaneous clients. We also implemented collaborative features such as control locking, chatting, annotation etc. Due to in part of the flexibility provided by the ParaView framework and the design features implemented in the prototype, we were able to support collaboration with multiple views, instead of a simple give as initially proposed in Phase I. In this section we will summarize the results we obtained during the Phase I project. ParaView is complex, scalable, client-server application framework built on top of the VTK visualization engine. During the implementation of the Phase I prototype, we realized that the ParaView framework naturally supports collaboration technology; hence we were able to go beyond the proposed Phase I prototype in several ways. For example, we were able to support for multiple views, enable server-as well as client-side rendering, and manage up to four heterogeneous clients. The success we achieved with Phase I clearly demonstrated the technical feasibility of the ParaView based collaborative framework we are proposing in the Phase II effort. We also investigated using the web browser as one of the means of participating in a collaborative session. This would enable non-visualization experts to participate in the collaboration process without being intimidated by a complex application such as ParaView. Hence we also developed a prototype web visualization applet that makes it possible for interactive

  10. Development of CFD fire models for deterministic analyses of the cable issues in the nuclear power plant

    International Nuclear Information System (INIS)

    Lin, C.-H.; Ferng, Y.-M.; Pei, B.-S.

    2009-01-01

    Additional fire barriers of electrical cables are required for the nuclear power plants (NPPs) in Taiwan due to the separation requirements of Appendix R to 10 CFR Part 50. The risk-informed fire analysis (RIFA) may provide a viable method to resolve these fire barrier issues. However, it is necessary to perform the fire scenario analyses so that RIFA can quantitatively determine the risk related to the fire barrier wrap. The CFD fire models are then proposed in this paper to help the RIFA in resolving these issues. Three typical fire scenarios are selected to assess the present CFD models. Compared with the experimental data and other model's simulations, the present calculated results show reasonable agreements, rendering that present CFD fire models can provide the quantitative information for RIFA analyses to release the cable wrap requirements for NPPs

  11. Estimation of time to rupture in a fire using 6FIRE, a lumped parameter UF6 cylinder transient heat transfer/stress analysis model

    International Nuclear Information System (INIS)

    Williams, W.R.; Anderson, J.C.

    1995-01-01

    The transportation of UF 6 is subject to regulations requiring the evaluation of packaging under a sequence of hypothetical accident conditions including exposure to a 30-min 800 degree C (1475 degree F) fire [10 CFR 71.73(c)(3)]. An issue of continuing interest is whether bare cylinders can withstand such a fire without rupturing. To address this issue, a lumped parameter heat transfer/stress analysis model (6FIRE) has been developed to simulate heating to the point of rupture of a cylinder containing UF 6 when it is exposed to a fire. The model is described, then estimates of time to rupture are presented for various cylinder types, fire temperatures, and fill conditions. An assessment of the quantity of UF 6 released from containment after rupture is also presented. Further documentation of the model is referenced

  12. Implications of emission inventory choice for modeling fire-related pollution in the U.S.

    Science.gov (United States)

    Koplitz, S. N.; Nolte, C. G.; Pouliot, G.

    2017-12-01

    Wildland fires are a major source of fine particulate matter (PM2.5), one of the most harmful ambient pollutants for human health globally. Within the U.S., wildland fires can account for more than 30% of total annual PM2.5 emissions. In order to represent the influence of fire emissions on atmospheric composition, regional and global chemical transport models (CTMs) rely on fire emission inventories developed from estimates of burned area (i.e. fire size and location). Burned area can be estimated using a range of top-down and bottom-up approaches, including satellite-derived remote sensing and on-the-ground incident reports. While burned area estimates agree with each other reasonably well in the western U.S. (within 20-30% for most years during 2002-2014), estimates for the southern U.S. vary by more than a factor of 3. Differences in burned area estimation methods lead to significant variability in the spatial and temporal allocation of emissions across fire emission inventory platforms. In this work, we implement fire emission estimates for 2011 from three different products - the USEPA National Emission Inventory (NEI), the Fire INventory of NCAR (FINN), and the Global Fire Emission Database (GFED4s) - into the Community Multiscale Air Quality (CMAQ) model to quantify and characterize differences in simulated fire-related PM2.5 and ozone concentrations across the contiguous U.S. due solely to the emission inventory used. Preliminary results indicate that the estimated contribution to national annual average PM2.5 from wildland fire in 2011 is highest using GFED4s emissions (1.0 µg m-3) followed by NEI (0.7 µg m-3) and FINN (0.3 µg m-3), with comparisons varying significantly by region and season. Understanding the sensitivity of modeling fire-related PM2.5 and ozone in the U.S. to fire emission inventory choice will inform future efforts to assess the implications of present and future fire activity for air quality and human health at national and global

  13. Quantifying soil burn severity for hydrologic modeling to assess post-fire effects on sediment delivery

    Science.gov (United States)

    Dobre, Mariana; Brooks, Erin; Lew, Roger; Kolden, Crystal; Quinn, Dylan; Elliot, William; Robichaud, Pete

    2017-04-01

    Soil erosion is a secondary fire effect with great implications for many ecosystem resources. Depending on the burn severity, topography, and the weather immediately after the fire, soil erosion can impact municipal water supplies, degrade water quality, and reduce reservoirs' storage capacity. Scientists and managers use field and remotely sensed data to quickly assess post-fire burn severity in ecologically-sensitive areas. From these assessments, mitigation activities are implemented to minimize post-fire flood and soil erosion and to facilitate post-fire vegetation recovery. Alternatively, land managers can use fire behavior and spread models (e.g. FlamMap, FARSITE, FOFEM, or CONSUME) to identify sensitive areas a priori, and apply strategies such as fuel reduction treatments to proactively minimize the risk of wildfire spread and increased burn severity. There is a growing interest in linking fire behavior and spread models with hydrology-based soil erosion models to provide site-specific assessment of mitigation treatments on post-fire runoff and erosion. The challenge remains, however, that many burn severity mapping and modeling products quantify vegetation loss rather than measuring soil burn severity. Wildfire burn severity is spatially heterogeneous and depends on the pre-fire vegetation cover, fuel load, topography, and weather. Severities also differ depending on the variable of interest (e.g. soil, vegetation). In the United States, Burned Area Reflectance Classification (BARC) maps, derived from Landsat satellite images, are used as an initial burn severity assessment. BARC maps are classified from either a Normalized Burn Ratio (NBR) or differenced Normalized Burned Ratio (dNBR) scene into four classes (Unburned, Low, Moderate, and High severity). The development of soil burn severity maps requires further manual field validation efforts to transform the BARC maps into a product more applicable for post-fire soil rehabilitation activities

  14. A model of collaboration for the implementation of problem-based learning in nursing education in South Africa

    Directory of Open Access Journals (Sweden)

    Mahlasela A. Rakhudu

    2017-08-01

    Recommendations: Managerial commitment, training of collaborators on PBL and collaboration skills, memorandum of agreement, monitoring and evaluation are critical. More research is required to pilot the model and evaluate collaboration in implementing PBL at different levels of operations.

  15. Modelling of electrical cabinet fires based on the CARMELA experimental program

    International Nuclear Information System (INIS)

    Melis, S.; Rigollet, L.; Such, J.M.; Casselman, C.

    2004-01-01

    As fire of electrical cabinets causes some hazard to nuclear safety, IRSN has conducted the CARMELA program to investigate this topic. The program was carried out in three stages. The two first stages consisted in analytical experiments where the combustible was simulated by thin plastic pieces and where the different parameters that influence the fire could be easily varied. The third stage involved real relay cabinets. This article first describes the experimental facility and the test matrix. The phenomenology of electrical cabinet fires is then exposed and the most influencing parameters are identified from the analytical experiments: the ventilation comes at first rank but the materials involved are also shown to influence the propagation of the fire. The model developed to represent the fire, and particularly the rate of heat released, is then presented and the comparison of its results with the measurements performed in the experiments shows that its validity is acceptable. (orig.)

  16. Fire modeling for Building 221-T - T Plant Canyon Deck and Railroad Tunnel

    International Nuclear Information System (INIS)

    Oar, D.L.

    1994-01-01

    This report was prepared by Hughes Associates, Inc. to document the results of fire models for building 221-T Canyon Deck and Railroad Tunnel. Backup data is contained in document No. WHC-SD-CP-ANAL-010, Rev. 0

  17. An Interprofessional Approach to Business Planning: A Model of Collaboration

    Science.gov (United States)

    Ross, Cory; Alexander, Kathleen; Gritsyuk, Renata; Morrin, Arleen; Tan, Jackie

    2011-01-01

    George Brown College is among the leaders in the interprofessional health-care education movement in Canada. Interprofessional Education (IPE) and Collaborative Practice occur "when students from two or more professions learn about, from and with each other to enable effective collaboration and improve health outcomes." According to the…

  18. Improved spring model-based collaborative indoor visible light positioning

    Science.gov (United States)

    Luo, Zhijie; Zhang, WeiNan; Zhou, GuoFu

    2016-06-01

    Gaining accuracy with indoor positioning of individuals is important as many location-based services rely on the user's current position to provide them with useful services. Many researchers have studied indoor positioning techniques based on WiFi and Bluetooth. However, they have disadvantages such as low accuracy or high cost. In this paper, we propose an indoor positioning system in which visible light radiated from light-emitting diodes is used to locate the position of receivers. Compared with existing methods using light-emitting diode light, we present a high-precision and simple implementation collaborative indoor visible light positioning system based on an improved spring model. We first estimate coordinate position information using the visible light positioning system, and then use the spring model to correct positioning errors. The system can be employed easily because it does not require additional sensors and the occlusion problem of visible light would be alleviated. We also describe simulation experiments, which confirm the feasibility of our proposed method.

  19. A deterministric and probabilistric model for oilspill fires in nuclear power plants

    International Nuclear Information System (INIS)

    Karlsson, B.

    1988-03-01

    A deterministic and probabilistic model for oilspill fires in nuclear power plant compartments has been developed. It's objective is to predict whether certain components in the compartment will cease to function as a result of the fire and to give the probability of failure. Results are presented for several scenarios in two compartments. The model has been implimented in the computer code OSFIC, a tool for safety engineers to compare various component configurations in different compartments. (author)

  20. Simulating smoke transport from wildland fires with a regional-scale air quality model: sensitivity to spatiotemporal allocation of fire emissions.

    Science.gov (United States)

    Garcia-Menendez, Fernando; Hu, Yongtao; Odman, Mehmet T

    2014-09-15

    Air quality forecasts generated with chemical transport models can provide valuable information about the potential impacts of fires on pollutant levels. However, significant uncertainties are associated with fire-related emission estimates as well as their distribution on gridded modeling domains. In this study, we explore the sensitivity of fine particulate matter concentrations predicted by a regional-scale air quality model to the spatial and temporal allocation of fire emissions. The assessment was completed by simulating a fire-related smoke episode in which air quality throughout the Atlanta metropolitan area was affected on February 28, 2007. Sensitivity analyses were carried out to evaluate the significance of emission distribution among the model's vertical layers, along the horizontal plane, and into hourly inputs. Predicted PM2.5 concentrations were highly sensitive to emission injection altitude relative to planetary boundary layer height. Simulations were also responsive to the horizontal allocation of fire emissions and their distribution into single or multiple grid cells. Additionally, modeled concentrations were greatly sensitive to the temporal distribution of fire-related emissions. The analyses demonstrate that, in addition to adequate estimates of emitted mass, successfully modeling the impacts of fires on air quality depends on an accurate spatiotemporal allocation of emissions. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Phasic firing in vasopressin cells: understanding its functional significance through computational models.

    Directory of Open Access Journals (Sweden)

    Duncan J MacGregor

    Full Text Available Vasopressin neurons, responding to input generated by osmotic pressure, use an intrinsic mechanism to shift from slow irregular firing to a distinct phasic pattern, consisting of long bursts and silences lasting tens of seconds. With increased input, bursts lengthen, eventually shifting to continuous firing. The phasic activity remains asynchronous across the cells and is not reflected in the population output signal. Here we have used a computational vasopressin neuron model to investigate the functional significance of the phasic firing pattern. We generated a concise model of the synaptic input driven spike firing mechanism that gives a close quantitative match to vasopressin neuron spike activity recorded in vivo, tested against endogenous activity and experimental interventions. The integrate-and-fire based model provides a simple physiological explanation of the phasic firing mechanism involving an activity-dependent slow depolarising afterpotential (DAP generated by a calcium-inactivated potassium leak current. This is modulated by the slower, opposing, action of activity-dependent dendritic dynorphin release, which inactivates the DAP, the opposing effects generating successive periods of bursting and silence. Model cells are not spontaneously active, but fire when perturbed by random perturbations mimicking synaptic input. We constructed one population of such phasic neurons, and another population of similar cells but which lacked the ability to fire phasically. We then studied how these two populations differed in the way that they encoded changes in afferent inputs. By comparison with the non-phasic population, the phasic population responds linearly to increases in tonic synaptic input. Non-phasic cells respond to transient elevations in synaptic input in a way that strongly depends on background activity levels, phasic cells in a way that is independent of background levels, and show a similar strong linearization of the response

  2. Modelling the role of fires in the terrestrial carbon balance by incorporating SPITFIRE into the global vegetation modelORCHIDEE - Part 1: Simulating historical global burned area and fire regimes

    Science.gov (United States)

    C. Yue; P. Ciais; P. Cadule; K. Thonicke; S. Archibald; B. Poulter; W. M. Hao; S. Hantson; F. Mouillot; P. Friedlingstein; F. Maignan; N. Viovy

    2014-01-01

    Fire is an important global ecological process that influences the distribution of biomes, with consequences for carbon, water, and energy budgets. Therefore it is impossible to appropriately model the history and future of the terrestrial ecosystems and the climate system without including fire. This study incorporates the process-based prognostic fire module SPITFIRE...

  3. The Role of Temporal Evolution in Modeling Atmospheric Emissions from Tropical Fires

    Science.gov (United States)

    Marlier, Miriam E.; Voulgarakis, Apostolos; Shindell, Drew T.; Faluvegi, Gregory S.; Henry, Candise L.; Randerson, James T.

    2014-01-01

    Fire emissions associated with tropical land use change and maintenance influence atmospheric composition, air quality, and climate. In this study, we explore the effects of representing fire emissions at daily versus monthly resolution in a global composition-climate model. We find that simulations of aerosols are impacted more by the temporal resolution of fire emissions than trace gases such as carbon monoxide or ozone. Daily-resolved datasets concentrate emissions from fire events over shorter time periods and allow them to more realistically interact with model meteorology, reducing how often emissions are concurrently released with precipitation events and in turn increasing peak aerosol concentrations. The magnitude of this effect varies across tropical ecosystem types, ranging from smaller changes in modeling the low intensity, frequent burning typical of savanna ecosystems to larger differences when modeling the short-term, intense fires that characterize deforestation events. The utility of modeling fire emissions at a daily resolution also depends on the application, such as modeling exceedances of particulate matter concentrations over air quality guidelines or simulating regional atmospheric heating patterns.

  4. Mesh influence on the fire computer modeling in nuclear power plants

    Directory of Open Access Journals (Sweden)

    D. Lázaro

    2018-04-01

    Full Text Available Fire computer models allow to study real fire scenarios consequences. Its use in nuclear power plants has increased with the new regulations to apply risk informed performance-based methods for the analysis and design of fire safety solutions. The selection of the cell side factor is very important in these kinds of models. The mesh must establish a compromise between the geometry adjustment, the resolution of the equations and the computation times. This paper aims to study the impact of several cell sizes, using the fire computer model FDS, to evaluate the relative affectation in the final simulation results. In order to validate that, we have employed several scenarios of interest for nuclear power plants. Conclusions offer relevant data for users and show some cell sizes that can be selected to guarantee the quality of the simulations and reduce the results uncertainty.

  5. A Five-Year CMAQ PM2.5 Model Performance for Wildfires and Prescribed Fires

    Science.gov (United States)

    Wilkins, J. L.; Pouliot, G.; Foley, K.; Rappold, A.; Pierce, T. E.

    2016-12-01

    Biomass burning has been identified as an important contributor to the degradation of air quality because of its impact on ozone and particulate matter. Two components of the biomass burning inventory, wildfires and prescribed fires are routinely estimated in the national emissions inventory. However, there is a large amount of uncertainty in the development of these emission inventory sectors. We have completed a 5 year set of CMAQ model simulations (2008-2012) in which we have simulated regional air quality with and without the wildfire and prescribed fire inventory. We will examine CMAQ model performance over regions with significant PM2.5 and Ozone contribution from prescribed fires and wildfires. We will also review plume rise to see how it affects model bias and compare CMAQ current fire emissions input to an hourly dataset from FLAMBE.

  6. Modelling the ecological vulnerability to forest fires in mediterranean ecosystems using geographic information technologies.

    Science.gov (United States)

    Duguy, Beatriz; Alloza, José Antonio; Baeza, M Jaime; De la Riva, Juan; Echeverría, Maite; Ibarra, Paloma; Llovet, Juan; Cabello, Fernando Pérez; Rovira, Pere; Vallejo, Ramon V

    2012-12-01

    Forest fires represent a major driver of change at the ecosystem and landscape levels in the Mediterranean region. Environmental features and vegetation are key factors to estimate the ecological vulnerability to fire; defined as the degree to which an ecosystem is susceptible to, and unable to cope with, adverse effects of fire (provided a fire occurs). Given the predicted climatic changes for the region, it is urgent to validate spatially explicit tools for assessing this vulnerability in order to support the design of new fire prevention and restoration strategies. This work presents an innovative GIS-based modelling approach to evaluate the ecological vulnerability to fire of an ecosystem, considering its main components (soil and vegetation) and different time scales. The evaluation was structured in three stages: short-term (focussed on soil degradation risk), medium-term (focussed on changes in vegetation), and coupling of the short- and medium-term vulnerabilities. The model was implemented in two regions: Aragón (inland North-eastern Spain) and Valencia (eastern Spain). Maps of the ecological vulnerability to fire were produced at a regional scale. We partially validated the model in a study site combining two complementary approaches that focused on testing the adequacy of model's predictions in three ecosystems, all very common in fire-prone landscapes of eastern Spain: two shrublands and a pine forest. Both approaches were based on the comparison of model's predictions with values of NDVI (Normalized Difference Vegetation Index), which is considered a good proxy for green biomass. Both methods showed that the model's performance is satisfactory when applied to the three selected vegetation types.

  7. Modelling fire frequency and area burned across phytoclimatic regions in Spain using reanalysis data and the Canadian Fire Weather Index System

    Science.gov (United States)

    Bedia, J.; Herrera, S.; Gutiérrez, J. M.

    2013-09-01

    We develop fire occurrence and burned area models in peninsular Spain, an area of high variability in climate and fuel types, for the period 1990-2008. We based the analysis on a phytoclimatic classification aiming to the stratification of the territory into homogeneous units in terms of climatic and fuel type characteristics, allowing to test model performance under different climatic and fuel conditions. We used generalized linear models (GLM) and multivariate adaptive regression splines (MARS) as modelling algorithms and temperature, relative humidity, precipitation and wind speed, taken from the ERA-Interim reanalysis, as well as the components of the Canadian Forest Fire Weather Index (FWI) System as predictors. We also computed the standardized precipitation-evapotranspiration index (SPEI) as an additional predictor for the models of burned area. We found two contrasting fire regimes in terms of area burned and number of fires: one characterized by a bimodal annual pattern, characterizing the Nemoral and Oro-boreal phytoclimatic types, and another one exhibiting an unimodal annual cycle, with the fire season concentrated in the summer months in the Mediterranean and Arid regions. The fire occurrence models attained good skill in most of the phytoclimatic zones considered, yielding in some zones notably high correlation coefficients between the observed and modelled inter-annual fire frequencies. Total area burned also exhibited a high dependence on the meteorological drivers, although their ability to reproduce the observed annual burned area time series was poor in most cases. We identified temperature and some FWI system components as the most important explanatory variables, and also SPEI in some of the burned area models, highlighting the adequacy of the FWI system for fire modelling applications and leaving the door opened to the development a more complex modelling framework based on these predictors. Furthermore, we demonstrate the potential usefulness

  8. Simulating boreal forest carbon dynamics after stand-replacing fire disturbance : Insights from a global process-based vegetation model

    NARCIS (Netherlands)

    Yue, Chao; Ciais, P.; Luyssaert, S.; Cadule, Patricia; Harden, J. L.; Randerson, J.; Bellassen, V.; Wang, T.; Piao, S.L.; Poulter, B.; Viovy, N.

    2013-01-01

    Stand-replacing fires are the dominant fire type in North American boreal forests. They leave a historical legacy of a mosaic landscape of different aged forest cohorts. This forest age dynamics must be included in vegetation models to accurately quantify the role of fire in the historical and

  9. Linking sediment-charcoal records and ecological modeling to understand causes of fire-regime change in boreal forests

    Science.gov (United States)

    Linda B. Brubaker; Philip E. Higuera; T. Scott Rupp; Mark A. Olson; Patricia M. Anderson; Feng Sheng. Hu

    2009-01-01

    Interactions between vegetation and fire have the potential to overshadow direct effects of climate change on fire regimes in boreal forests of North America. We develop methods to compare sediment-charcoal records with fire regimes simulated by an ecological model, ALFRESCO (Alaskan Frame-based Ecosystem Code) and apply these methods to evaluate potential causes of a...

  10. Exergetic Modelling of Oil-Fired Steam Boilers | Ohijeagbon ...

    African Journals Online (AJOL)

    The performance variables and potential for energy savings in oil-fired industrial steam boilers were studied. Operational parameters of steam boilers using low pour fuel oil (LPFO) and diesel were used to determine thermodynamic properties of material streams and exergetic parameters. Analysis of thermodynamic ...

  11. Clarifying evacuation options through fire behavior and traffic modeling

    Science.gov (United States)

    Carol L. Rice; Ronny J. Coleman; Mike. Price

    2011-01-01

    Communities are becoming increasingly concerned with the variety of choices related to wildfire evacuation. We used ArcView with Network Analyst to evaluate the different options for evacuations during wildfire in a case study community. We tested overlaying fire growth patterns with the road network and population characteristics to determine recommendations for...

  12. Field validation of a free-agent cellular automata model of fire spread with fire–atmosphere coupling

    Science.gov (United States)

    Gary Achtemeier

    2012-01-01

    A cellular automata fire model represents ‘elements’ of fire by autonomous agents. A few simple algebraic expressions substituted for complex physical and meteorological processes and solved iteratively yield simulations for ‘super-diffusive’ fire spread and coupled surface-layer (2-m) fire–atmosphere processes. Pressure anomalies, which are integrals of the thermal...

  13. ICTP: A Successful Model of International Scientific Collaboration

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    The importance of international scientific collaboration in the changing world where the centre of gravity of fundamental research may be moving towards the east and the south is addressed. The unique role of ICTP in supporting global science is highlighted.

  14. Overview of Business Process Modeling Languages Supporting Enterprise Collaboration

    NARCIS (Netherlands)

    Soleimani Malekan, H.; Afsarmanesh, H.; Shishkov, B.

    2014-01-01

    Enterprises endeavor to provide innovative services and competitive advantages, by constituting Collaborative Networks (CNs). Each enterprise performs a set of Business Processes (BPs), and through developing integrated BPs in CNs, enterprises can jointly produce stronger capabilities. However,

  15. Next-generation models for Canadian collaboration in international ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... enhanced and sustained collaboration between Canadian civil society and academia. ... with particular emphasis on the civil society and academic communities; ... in the fields of science, technology, engineering, and mathematics (STEM).

  16. Language Modelling for Collaborative Filtering: Application to Job Applicant Matching

    OpenAIRE

    Schmitt , Thomas; Gonard , François; Caillou , Philippe; Sebag , Michèle

    2017-01-01

    International audience; This paper addresses a collaborative retrieval problem , the recommendation of job ads to applicants. Specifically, two proprietary databases are considered. The first one focuses on the context of unskilled low-paid jobs/applicants; the second one focuses on highly qualified jobs/applicants. Each database includes the job ads and applicant resumes together with the collaborative filtering data recording the applicant clicks on job ads. The proposed approach, called LA...

  17. A Model for Collaborative Working to Facilitate Knowledge Mobilisation in Public Health

    Science.gov (United States)

    McCabe, Karen Elizabeth; Wallace, Annie; Crosland, Ann

    2015-01-01

    This paper introduces a model for collaborative working to facilitate knowledge mobilisation in public health. The model has been developed by university researchers who worked collaboratively with public health commissioners and strategic partners to evaluate a portfolio of short-term funded interventions to inform re-commissioning. Within this…

  18. The Proposed Model of Collaborative Virtual Learning Environment for Introductory Programming Course

    Science.gov (United States)

    Othman, Mahfudzah; Othman, Muhaini

    2012-01-01

    This paper discusses the proposed model of the collaborative virtual learning system for the introductory computer programming course which uses one of the collaborative learning techniques known as the "Think-Pair-Share". The main objective of this study is to design a model for an online learning system that facilitates the…

  19. Modeling very large-fire occurrences over the continental United States from weather and climate forcing

    International Nuclear Information System (INIS)

    Barbero, R; Abatzoglou, J T; Steel, E A; K Larkin, Narasimhan

    2014-01-01

    Very large-fires (VLFs) have widespread impacts on ecosystems, air quality, fire suppression resources, and in many regions account for a majority of total area burned. Empirical generalized linear models of the largest fires (>5000 ha) across the contiguous United States (US) were developed at ∼60 km spatial and weekly temporal resolutions using solely atmospheric predictors. Climate−fire relationships on interannual timescales were evident, with wetter conditions than normal in the previous growing season enhancing VLFs probability in rangeland systems and with concurrent long-term drought enhancing VLFs probability in forested systems. Information at sub-seasonal timescales further refined these relationships, with short-term fire weather being a significant predictor in rangelands and fire danger indices linked to dead fuel moisture being a significant predictor in forested lands. Models demonstrated agreement in capturing the observed spatial and temporal variability including the interannual variability of VLF occurrences within most ecoregions. Furthermore the model captured the observed increase in VLF occurrences across parts of the southwestern and southeastern US from 1984 to 2010 suggesting that, irrespective of changes in fuels and land management, climatic factors have become more favorable for VLF occurrence over the past three decades in some regions. Our modeling framework provides a basis for simulations of future VLF occurrences from climate projections. (letter)

  20. Mapping and Analysis of Forest and Land Fire Potential Using Geospatial Technology and Mathematical Modeling

    International Nuclear Information System (INIS)

    Suliman, M D H; Mahmud, M; Reba, M N M; S, L W

    2014-01-01

    Forest and land fire can cause negative implications for forest ecosystems, biodiversity, air quality and soil structure. However, the implications involved can be minimized through effective disaster management system. Effective disaster management mechanisms can be developed through appropriate early warning system as well as an efficient delivery system. This study tried to focus on two aspects, namely by mapping the potential of forest fire and land as well as the delivery of information to users through WebGIS application. Geospatial technology and mathematical modeling used in this study for identifying, classifying and mapping the potential area for burning. Mathematical models used is the Analytical Hierarchy Process (AHP), while Geospatial technologies involved include remote sensing, Geographic Information System (GIS) and digital field data collection. The entire Selangor state was chosen as our study area based on a number of cases have been reported over the last two decades. AHP modeling to assess the comparison between the three main criteria of fuel, topography and human factors design. Contributions of experts directly involved in forest fire fighting operations and land comprising officials from the Fire and Rescue Department Malaysia also evaluated in this model. The study found that about 32.83 square kilometers of the total area of Selangor state are the extreme potential for fire. Extreme potential areas identified are in Bestari Jaya and Kuala Langat High Ulu. Continuity of information and terrestrial forest fire potential was displayed in WebGIS applications on the internet. Display information through WebGIS applications is a better approach to help the decision-making process at a high level of confidence and approximate real conditions. Agencies involved in disaster management such as Jawatankuasa Pengurusan Dan Bantuan Bencana (JPBB) of District, State and the National under the National Security Division and the Fire and Rescue

  1. Mapping and Analysis of Forest and Land Fire Potential Using Geospatial Technology and Mathematical Modeling

    Science.gov (United States)

    Suliman, M. D. H.; Mahmud, M.; Reba, M. N. M.; S, L. W.

    2014-02-01

    Forest and land fire can cause negative implications for forest ecosystems, biodiversity, air quality and soil structure. However, the implications involved can be minimized through effective disaster management system. Effective disaster management mechanisms can be developed through appropriate early warning system as well as an efficient delivery system. This study tried to focus on two aspects, namely by mapping the potential of forest fire and land as well as the delivery of information to users through WebGIS application. Geospatial technology and mathematical modeling used in this study for identifying, classifying and mapping the potential area for burning. Mathematical models used is the Analytical Hierarchy Process (AHP), while Geospatial technologies involved include remote sensing, Geographic Information System (GIS) and digital field data collection. The entire Selangor state was chosen as our study area based on a number of cases have been reported over the last two decades. AHP modeling to assess the comparison between the three main criteria of fuel, topography and human factors design. Contributions of experts directly involved in forest fire fighting operations and land comprising officials from the Fire and Rescue Department Malaysia also evaluated in this model. The study found that about 32.83 square kilometers of the total area of Selangor state are the extreme potential for fire. Extreme potential areas identified are in Bestari Jaya and Kuala Langat High Ulu. Continuity of information and terrestrial forest fire potential was displayed in WebGIS applications on the internet. Display information through WebGIS applications is a better approach to help the decision-making process at a high level of confidence and approximate real conditions. Agencies involved in disaster management such as Jawatankuasa Pengurusan Dan Bantuan Bencana (JPBB) of District, State and the National under the National Security Division and the Fire and Rescue

  2. MODELING ECONOMIC AND ECOLOGICAL BENEFITS OF POST-FIRE REVEGETATION IN THE GREAT BASIN

    OpenAIRE

    Niell, Rebecca; Englin, Jeffrey E.; Nalle, Darek

    2004-01-01

    This study employs a Markov chain model of vegetation dynamics to examine the economic and ecological benefits of post-fire revegetation in the Great Basin sagebrush steppe. The analysis is important because synergies between wildland fire and invasive weeds in this ecosystem are likely to result in the loss of native biodiversity, less predictable forage availability for livestock and wildlife, reduced watershed stability and water quality, and increased costs and risk associated with firefi...

  3. The simulation of surface fire spread based on Rothermel model in windthrow area of Changbai Mountain (Jilin, China)

    Science.gov (United States)

    Yin, Hang; Jin, Hui; Zhao, Ying; Fan, Yuguang; Qin, Liwu; Chen, Qinghong; Huang, Liya; Jia, Xiang; Liu, Lijie; Dai, Yuhong; Xiao, Ying

    2018-03-01

    The forest-fire not only brings great loss to natural resources, but also destructs the ecosystem and reduces the soil fertility, causing some natural disasters as soil erosion and debris flow. However, due to the lack of the prognosis for forest fire spreading trend in forest fire fighting, it is difficult to formulate rational and effective fire-fighting scheme. In the event of forest fire, achieving accurate judgment to the fire behavior would greatly improve the fire-fighting efficiency, and reduce heavy losses caused by fire. Researches on forest fire spread simulation can effectively reduce the loss of disasters. The present study focused on the simulation of "29 May 2012" wildfire in windthrow area of Changbai Mountain. Basic data were retrieved from the "29 May 2012" wildfire and field survey. A self-development forest fire behavior simulated program based on Rothermel Model was used in the simulation. Kappa coefficient and Sørensen index were employed to evaluate the simulation accuracy. The results showed that: The perimeter of simulated burned area was 4.66 km, the area was 56.47 hm2 and the overlapped burned area was 33.68 hm2, and the estimated rate of fire spread was 0.259 m/s. Between the simulated fire and actual fire, the Kappa coefficient was 0.7398 and the Sørensen co-efficient was 0.7419. This proved the application of Rothermel model to conduct fire behavior simulation in windthrow meadow was feasible. It can achieve the goal of forecasting for the spread behavior in windthrow area of Changbai Mountain. Thus, our self-development program based on the Rothermel model can provide a effective forecast of fire spread, which will facilitate the fire suppression work.

  4. Modeling mechanisms of vegetation change due to fire in a semi-arid ecosystem

    Science.gov (United States)

    White, J.D.; Gutzwiller, K.J.; Barrow, W.C.; Randall, L.J.; Swint, P.

    2008-01-01

    Vegetation growth and community composition in semi-arid environments is determined by water availability and carbon assimilation mechanisms specific to different plant types. Disturbance also impacts vegetation productivity and composition dependent on area affected, intensity, and frequency factors. In this study, a new spatially explicit ecosystem model is presented for the purpose of simulating vegetation cover type changes associated with fire disturbance in the northern Chihuahuan Desert region. The model is called the Landscape and Fire Simulator (LAFS) and represents physiological activity of six functional plant types incorporating site climate, fire, and seed dispersal routines for individual grid cells. We applied this model for Big Bend National Park, Texas, by assessing the impact of wildfire on the trajectory of vegetation communities over time. The model was initialized and calibrated based on landcover maps derived from Landsat-5 Thematic Mapper data acquired in 1986 and 1999 coupled with plant biomass measurements collected in the field during 2000. Initial vegetation cover change analysis from satellite data showed shrub encroachment during this time period that was captured in the simulated results. A synthetic 50-year climate record was derived from historical meteorological data to assess system response based on initial landcover conditions. This simulation showed that shrublands increased to the detriment of grass and yucca-ocotillo vegetation cover types indicating an ecosystem-level trajectory for shrub encroachment. Our analysis of simulated fires also showed that fires significantly reduced site biomass components including leaf area, stem, and seed biomass in this semi-arid ecosystem. In contrast to other landscape simulation models, this new model incorporates detailed physiological responses of functional plant types that will allow us to simulated the impact of increased atmospheric CO2 occurring with climate change coupled with fire

  5. System Thinking and Business Model Canvas for Collaborative Business Models Design

    OpenAIRE

    Pereira , Sergio; Medina , Franciele; Gonçalves , Rodrigo ,; Silva , Márcia

    2016-01-01

    Part 10: Collaborative Systems; International audience; The purpose of this research is to reduce the existing gap between the abstraction of the real world and business modeling. For that, we combine two solutions: the soft systems methodology (SSM) and business model canvas (BMC). The first step is to introduce the theoretical concepts of both. The second step is the application of each methodology separately. Moreover, the final stage is to feed the BMC with the outputs of SSM. Was verifie...

  6. A Conceptual Model for Bidirectional Service, Information and Product Quality in an IS Outsourcing Collaboration Environment

    OpenAIRE

    Subrata Chakrabarty

    2009-01-01

    This paper advances theory on the process of collaboration between entities and its implications on the quality of services, information, and/or products (SIPs) that the collaborating entities provide to each other. It investigates the scenario of outsourced IS projects (such as custom software development) where the extent of collaboration between a client and vendor is high. Using the social exchange theory, the proposed conceptual model tries to establish the "bidirectional" nature of SIP ...

  7. Application of CFD Modeling to Room Fire Growth on Walls

    Science.gov (United States)

    2003-04-01

    to each particle. For fires of other geometries, expressions must be available for representing the characteristic velocity and flame length , in the...burning time, z , is the flame length , ri,, is the selected particle rate. The velocity of the particles generally depends on their launch site. But if...over the characteristic flame length , We used R* = 0.05 or 20 cells over the characteristic flame length . In FDS 2.0 the stoichiometric mixture

  8. Numerical modelling of a straw-fired grate boiler

    DEFF Research Database (Denmark)

    Kær, Søren Knudsen

    2004-01-01

    The paper presents a computational fluid dynamics (CFD) analysis of a 33 MW straw-fired grate boiler. Combustion on the grate plays akey-role in the analysis of these boilers and in this work a stand-alone code was used to provide inlet conditions for the CFD analysis. Modelpredictions were compa...... mixing in the furnace is a key issue leading to these problems. q 2003 Elsevier Ltd. All rights reserved....

  9. Convective effects in a regulatory and proposed fire model

    International Nuclear Information System (INIS)

    Wix, S.D.; Hohnstreiter, G.F.

    1995-01-01

    Radiation is the dominant mode of heat transfer in large fires. However, convection can be as much as 10 to 20 percent of the total heat transfer to an object in a large fire. The current radioactive material transportation packaging regulations include convection as a mode of heat transfer in the accident condition scenario. The current International Atomic Energy Agency Safety Series 6 packaging regulation states ''the convection coefficient shall be that value which the designer can justify if the package were exposed to the specified fire''. The current Title 10, Code of Federal Regulations, Part 71 (10CFR71) packaging regulation states ''when significant, convection heat input must be included on the basis of still, ambient air at 800 degrees C (1475 degrees F)''. Two questions that can arise in an analysts mind from an examination of the packaging regulations is whether convection is significant and whether convection should be included in the design analysis of a radioactive materials transportation container. The objective of this study is to examine the convective effects on an actual radioactive materials transportation package using a regulatory and a proposed thermal boundary condition

  10. A methodology proposal for collaborative business process elaboration using a model-driven approach

    Science.gov (United States)

    Mu, Wenxin; Bénaben, Frédérick; Pingaud, Hervé

    2015-05-01

    Business process management (BPM) principles are commonly used to improve processes within an organisation. But they can equally be applied to supporting the design of an Information System (IS). In a collaborative situation involving several partners, this type of BPM approach may be useful to support the design of a Mediation Information System (MIS), which would ensure interoperability between the partners' ISs (which are assumed to be service oriented). To achieve this objective, the first main task is to build a collaborative business process cartography. The aim of this article is to present a method for bringing together collaborative information and elaborating collaborative business processes from the information gathered (by using a collaborative situation framework, an organisational model, an informational model, a functional model and a metamodel and by using model transformation rules).

  11. Crown Fire Potential

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Crown fire potential was modeled using FlamMap, an interagency fire behavior mapping and analysis program that computes potential fire behavior characteristics. The...

  12. A Partially-Stirred Batch Reactor Model for Under-Ventilated Fire Dynamics

    Science.gov (United States)

    McDermott, Randall; Weinschenk, Craig

    2013-11-01

    A simple discrete quadrature method is developed for closure of the mean chemical source term in large-eddy simulations (LES) and implemented in the publicly available fire model, Fire Dynamics Simulator (FDS). The method is cast as a partially-stirred batch reactor model for each computational cell. The model has three distinct components: (1) a subgrid mixing environment, (2) a mixing model, and (3) a set of chemical rate laws. The subgrid probability density function (PDF) is described by a linear combination of Dirac delta functions with quadrature weights set to satisfy simple integral constraints for the computational cell. It is shown that under certain limiting assumptions, the present method reduces to the eddy dissipation concept (EDC). The model is used to predict carbon monoxide concentrations in direct numerical simulation (DNS) of a methane slot burner and in LES of an under-ventilated compartment fire.

  13. Electrical modeling of semiconductor bridge (SCB) BNCP detonators with electrochemical capacitor firing sets

    Energy Technology Data Exchange (ETDEWEB)

    Marx, K.D. [Sandia National Labs., Livermore, CA (United States); Ingersoll, D.; Bickes, R.W. Jr. [Sandia National Labs., Albuquerque, NM (United States)

    1998-11-01

    In this paper the authors describe computer models that simulate the electrical characteristics and hence, the firing characteristics and performance of a semiconductor bridge (SCB) detonator for the initiation of BNCP [tetraammine-cis-bis (5-nitro-2H-tetrazolato-N{sup 2}) cobalt(III) perchlorate]. The electrical data and resultant models provide new insights into the fundamental behavior of SCB detonators, particularly with respect to the initiation mechanism and the interaction of the explosive powder with the SCB. One model developed, the Thermal Feedback Model, considers the total energy budget for the system, including the time evolution of the energy delivered to the powder by the electrical circuit, as well as that released by the ignition and subsequent chemical reaction of the powder. The authors also present data obtained using a new low-voltage firing set which employed an advanced electrochemical capacitor having a nominal capacitance of 350,000 {micro}F at 9 V, the maximum voltage rating for this particular device. A model for this firing set and detonator was developed by making measurements of the intrinsic capacitance and equivalent series resistance (ESR < 10 m{Omega}) of a single device. This model was then used to predict the behavior of BNCP SCB detonators fired alone, as well as in a multishot, parallel-string configuration using a firing set composed of either a single 9 V electrochemical capacitor or two of the capacitors wired in series and charged to 18 V.

  14. Testing woody fuel consumption models for application in Australian southern eucalypt forest fires

    Science.gov (United States)

    J.J. Hollis; S. Matthews; Roger Ottmar; S.J. Prichard; S. Slijepcevic; N.D. Burrows; B. Ward; K.G. Tolhurst; W.R. Anderson; J S. Gould

    2010-01-01

    Five models for the consumption of coarse woody debris or woody fuels with a diameter larger than 0.6 cm were assessed for application in Australian southern eucalypt forest fires including: CONSUME models for (1) activity fuels, (2) natural western woody and (3) natural southern woody fuels, (4) the BURNUP model and (5) the recommendation by the Australian National...

  15. Codimension-two bifurcation analysis on firing activities in Chay neuron model

    International Nuclear Information System (INIS)

    Duan Lixia; Lu Qishao

    2006-01-01

    Using codimension-two bifurcation analysis in the Chay neuron model, the relationship between the electric activities and the parameters of neurons is revealed. The whole parameter space is divided into two parts, that is, the firing and silence regions of neurons. It is found that the transition sets between firing and silence regions are composed of the Hopf bifurcation curves of equilibrium states and the saddle-node bifurcation curves of limit cycles, with some codimension-two bifurcation points. The transitions from silence to firing in neurons are due to the Hopf bifurcation or the fold limit cycle bifurcation, but the codimension-two singularities lead to complexity in dynamical behaviour of neuronal firing

  16. A fire risk assessment model for residential high-rises with a single stairwell

    DEFF Research Database (Denmark)

    Hansen, N. D.; Steffensen, F.B.; Valkvist, M.B.

    2018-01-01

    As few or none prescriptive guidelines for fire risk assessment of residential high-rise buildings exist, it has been unclear which fire safety design features constitute an acceptable (adequate) safety level. In order to fill this gap a simplified risk-based decision-support tool, the Fire Risk...... Model (FRM), was developed. The FRM evaluates both the risk level to the occupants and the property risk level as a function of the building characteristics, height and fire safety features for single stairwell residential high-rise buildings. The acceptability of a high-rise design is then defined......, and the associated performance of the FRM evaluated. It was found that compartmentation and the door configurations in the egress path play an important role, along with sprinklers, in order for the design to successfully keep the stairwell free from smoke. Specifically, modern curtain wall facades were found...

  17. Codimension-two bifurcation analysis on firing activities in Chay neuron model

    Energy Technology Data Exchange (ETDEWEB)

    Duan Lixia [School of Science, Beijing University of Aeronautics and Astronautics, Beijing 100083 (China); Lu Qishao [School of Science, Beijing University of Aeronautics and Astronautics, Beijing 100083 (China)]. E-mail: qishaolu@hotmail.com

    2006-12-15

    Using codimension-two bifurcation analysis in the Chay neuron model, the relationship between the electric activities and the parameters of neurons is revealed. The whole parameter space is divided into two parts, that is, the firing and silence regions of neurons. It is found that the transition sets between firing and silence regions are composed of the Hopf bifurcation curves of equilibrium states and the saddle-node bifurcation curves of limit cycles, with some codimension-two bifurcation points. The transitions from silence to firing in neurons are due to the Hopf bifurcation or the fold limit cycle bifurcation, but the codimension-two singularities lead to complexity in dynamical behaviour of neuronal firing.

  18. Application of fire models for risk analysis in french nuclear power plants

    International Nuclear Information System (INIS)

    Brauns, P.

    1989-04-01

    Numerical simulations of compartment fires have been carried out in the French 900 MW and 1 300 MW nuclear power plants, to obtain quantitative data about this particular kind of risk: characteristic spreading times from one redundant electrical train to the other one, behaviour of important electrical components... The main stages of both studies were the following: selection of rooms, the location or function of which are essential for the plant safety in case of fire, on-site inspections to collect information about these rooms (amount of fuel, openings...), definition of fire scenarios, improvement of the fire model VESTA-PLUS, and, finally calculations using this computer code. The simulations have shown two major trends: i) the spreading times, without taking into account any external intervention, are always greater than half an hour, and ii) the specific design of the 1 300 MW power plants generally prevents one of the redundant train from being damaged due to a fire occurring in a room containing the other one. Examples of typical results obtained are given, showing the capability of application of the improved fire model to complex problems

  19. WRF-based fire risk modelling and evaluation for years 2010 and 2012 in Poland

    Science.gov (United States)

    Stec, Magdalena; Szymanowski, Mariusz; Kryza, Maciej

    2016-04-01

    Wildfires are one of the main ecosystems' disturbances for forested, seminatural and agricultural areas. They generate significant economic loss, especially in forest management and agriculture. Forest fire risk modeling is therefore essential e.g. for forestry administration. In August 2015 a new method of forest fire risk forecasting entered into force in Poland. The method allows to predict a fire risk level in a 4-degree scale (0 - no risk, 3 - highest risk) and consists of a set of linearized regression equations. Meteorological information is used as predictors in regression equations, with air temperature, relative humidity, average wind speed, cloudiness and rainfall. The equations include also pine litter humidity as a measure of potential fuel characteristics. All these parameters are measured routinely in Poland at 42 basic and 94 auxiliary sites. The fire risk level is estimated for a current (basing on morning measurements) or next day (basing on midday measurements). Entire country is divided into 42 prognostic zones, and fire risk level for each zone is taken from the closest measuring site. The first goal of this work is to assess if the measurements needed for fire risk forecasting may be replaced by the data from mesoscale meteorological model. Additionally, the use of a meteorological model would allow to take into account much more realistic spatial differentiation of weather elements determining the fire risk level instead of discrete point-made measurements. Meteorological data have been calculated using the Weather Research and Forecasting model (WRF). For the purpose of this study the WRF model is run in the reanalysis mode allowing to estimate all required meteorological data in a 5-kilometers grid. The only parameter that cannot be directly calculated using WRF is the litter humidity, which has been estimated using empirical formula developed by Sakowska (2007). The experiments are carried out for two selected years: 2010 and 2012. The

  20. Report on Integrating Activities and Models for Collaboration

    DEFF Research Database (Denmark)

    Buus, Lillian; Dirckinck-Holmfeld, Lone; Ryberg, Thomas

    This report is the deliverable for work package (WP) 28.3 “Integrated network and activities for the exchange of and collaboration between Master students, PhD students and professors” of the European Research Team (ERT) on Conditions for Productive Networked Learning Environments. The objective...... of WP28.3 is to build up an integrated network and activities for the exchange and collaboration between Master students, professional masters, PhD students and professors and to establish a virtual community around the research area of conditions for productive learning in networked learning...

  1. Exploring Early Angiosperm Fire Feedbacks using Coupled Experiments and Modelling Approaches to Estimate Cretaceous Palaeofire Behaviour

    Science.gov (United States)

    Belcher, Claire; Hudpsith, Victoria

    2016-04-01

    Using the fossil record we are typically limited to exploring linkages between palaeoecological changes and palaeofire activity by assessing the abundance of charcoals preserved in sediments. However, it is the behaviour of fires that primarily governs their ecological effects. Therefore, the ability to estimate variations in aspects of palaeofire behaviour such as palaeofire intensity and rate of spread would be of key benefit toward understanding the coupled evolutionary history of ecosystems and fire. The Cretaceous Period saw major diversification in land plants. Previously, conifers (gymnosperms) and ferns (pteridophytes) dominated Earth's ecosystems until flowering plants (angiosperms) appear in the fossil record of the Early Cretaceous (~135Ma). We have created surface fire behaviour estimates for a variety of angiosperm invasion scenarios and explored the influence of Cretaceous superambient atmospheric oxygen levels on the fire behaviour occurring in these new Cretaceous ecosystems. These estimates are then used to explore the hypothesis that the early spread of the angiosperms was promoted by the novel fire regimes that they created. In order to achieve this we tested the flammability of Mesozoic analogue fuel types in controlled laboratory experiments using an iCone calorimeter, which measured the ignitability as well as the effective heat of combustion of the fuels. We then used the BehavePlus fire behaviour modelling system to scale up our laboratory results to the ecosystem scale. Our results suggest that fire-angiosperm feedbacks may have occurred in two phases: The first phase being a result of weedy angiosperms providing an additional easily ignitable fuel that enhanced both the seasonality and frequency of surface fires. In the second phase, the addition of shrubby understory fuels likely expanded the number of ecosystems experiencing more intense surface fires, resulting in enhanced mortality and suppressed post-fire recruitment of gymnosperms

  2. [Forest lighting fire forecasting for Daxing'anling Mountains based on MAXENT model].

    Science.gov (United States)

    Sun, Yu; Shi, Ming-Chang; Peng, Huan; Zhu, Pei-Lin; Liu, Si-Lin; Wu, Shi-Lei; He, Cheng; Chen, Feng

    2014-04-01

    Daxing'anling Mountains is one of the areas with the highest occurrence of forest lighting fire in Heilongjiang Province, and developing a lightning fire forecast model to accurately predict the forest fires in this area is of importance. Based on the data of forest lightning fires and environment variables, the MAXENT model was used to predict the lightning fire in Daxing' anling region. Firstly, we studied the collinear diagnostic of each environment variable, evaluated the importance of the environmental variables using training gain and the Jackknife method, and then evaluated the prediction accuracy of the MAXENT model using the max Kappa value and the AUC value. The results showed that the variance inflation factor (VIF) values of lightning energy and neutralized charge were 5.012 and 6.230, respectively. They were collinear with the other variables, so the model could not be used for training. Daily rainfall, the number of cloud-to-ground lightning, and current intensity of cloud-to-ground lightning were the three most important factors affecting the lightning fires in the forest, while the daily average wind speed and the slope was of less importance. With the increase of the proportion of test data, the max Kappa and AUC values were increased. The max Kappa values were above 0.75 and the average value was 0.772, while all of the AUC values were above 0.5 and the average value was 0. 859. With a moderate level of prediction accuracy being achieved, the MAXENT model could be used to predict forest lightning fire in Daxing'anling Mountains.

  3. Collaborative Cloud Manufacturing: Design of Business Model Innovations Enabled by Cyberphysical Systems in Distributed Manufacturing Systems

    Directory of Open Access Journals (Sweden)

    Erwin Rauch

    2016-01-01

    Full Text Available Collaborative cloud manufacturing, as a concept of distributed manufacturing, allows different opportunities for changing the logic of generating and capturing value. Cyberphysical systems and the technologies behind them are the enablers for new business models which have the potential to be disruptive. This paper introduces the topics of distributed manufacturing as well as cyberphysical systems. Furthermore, the main business model clusters of distributed manufacturing systems are described, including collaborative cloud manufacturing. The paper aims to provide support for developing business model innovations based on collaborative cloud manufacturing. Therefore, three business model architecture types of a differentiated business logic are discussed, taking into consideration the parameters which have an influence and the design of the business model and its architecture. As a result, new business models can be developed systematically and new ideas can be generated to boost the concept of collaborative cloud manufacturing within all sustainable business models.

  4. Project-oriented management of industrial production of fire and rescue equipment by means of geometric modelling

    OpenAIRE

    Rak, Iu; Bondarenko, V.

    2013-01-01

    Objective: The objective of the research is to develop a method based on the geometric modelling for the purpose of improving the effectiveness of fire protection project management in industrial production of fire protection technology systems. Methods: The theoretical inheritance mode of effective management in project-organizational structure of fire protection and specialized technical equipment production using geometric modelling. Results: Mathematical and geometric models of project ma...

  5. Resource Allocation Optimization Model of Collaborative Logistics Network Based on Bilevel Programming

    Directory of Open Access Journals (Sweden)

    Xiao-feng Xu

    2017-01-01

    Full Text Available Collaborative logistics network resource allocation can effectively meet the needs of customers. It can realize the overall benefit maximization of the logistics network and ensure that collaborative logistics network runs orderly at the time of creating value. Therefore, this article is based on the relationship of collaborative logistics network supplier, the transit warehouse, and sellers, and we consider the uncertainty of time to establish a bilevel programming model with random constraints and propose a genetic simulated annealing hybrid intelligent algorithm to solve it. Numerical example shows that the method has stronger robustness and convergence; it can achieve collaborative logistics network resource allocation rationalization and optimization.

  6. Application of Different HSI Color Models to Detect Fire-Damaged Mortar

    Directory of Open Access Journals (Sweden)

    H. Luo

    2013-12-01

    Full Text Available To obtain a better understanding of the effect of vehicle fires on rigid pavement, a nondestructive test method utilizing an ordinary digital camera to capture images of mortar at five elevated temperatures was undertaken. These images were then analyzed by “image color-intensity analyzer” software. In image analysis, the RGB color model was the basic system used to represent the color information of images. HSI is a derived-color model that is transformed from an RGB model by formulae. In order to understand more about surface color changes and temperatures after a vehicle fire, various transformation formulae used in different research areas were applied in this study. They were then evaluated to obtain the optimum HSI model for further studies of fire-damaged mortar through the use of image analysis.

  7. Numerical prediction of heat-flux to massive calorimeters engulfed in regulatory fires with the cask analysis fire environment (CAFE) model

    International Nuclear Information System (INIS)

    Koski, Jorman A.; Suo-Antitla, Ahti; Kramer M, Alex; Greiner, Miles

    2000-01-01

    Recent observations show that the thermal boundary conditions within large-scale fires are significantly affected by the presence of thermally massive objects. These objects cool the soot and gas near their surfaces, and these effects reduce the incoming radiant heat-flux to values lower than the levels expected from simple σT fire 4 models. They also affect the flow and temperature fields in the fire far from their surfaces. The Cask Analysis Fire Environment (CAFE) code has been developed at Sandia National Laboratories to provide an enhanced fire boundary condition for the design of radioactive material packages. CAFE is a set of computer subroutines that use computational fluid mechanics methods to predict convective heat transfer and mixing. It also includes models for fuel and oxygen transport, chemical reaction, and participating-media radiation heat transfer. This code uses two-dimensional computational models so that it has reasonably short turnaround times on standard workstations and is well suited for design and risk studies. In this paper, CAFE is coupled with a commercial finite-element program to model a large cylindrical calorimeter fully engulfed in a pool fire. The time-dependent heat-flux to the calorimeter and the calorimeter surface temperature are determined for several locations around the calorimeter circumference. The variation of heat-flux with location is determined for calorimeters with different diameters and wall thickness, and the observed effects discussed

  8. Empirical Modelling of Inter-organizational Knowledge Collaboration

    NARCIS (Netherlands)

    Haghighi Talab, A.

    2017-01-01

    Open innovation, knowledge co-creation, and research joint ven-tures, unified under the term 'inter-organizational knowledge collaboration', are discussed in various fields of innovation man-agement to ultimately shape inno-vation strategy of the organiza-tions and the innovation policy.

  9. Anesthesia Nursing: A Collaborative Model for Graduate Education.

    Science.gov (United States)

    Chamings, Patricia A.; And Others

    1989-01-01

    The authors describe development of a collaborative graduate concentration in anesthesia nursing involving North Carolina Baptist Hospital and the University of North Carolina at Greensboro. Project components included (1) developing a cohesive faculty work group, (2) developing the curriculum, and (3) combining resources through an administrative…

  10. Model-based systems engineering to design collaborative robotics applications

    NARCIS (Netherlands)

    Hernandez Corbato, Carlos; Fernandez-Sanchez, Jose Luis; Rassa, Bob; Carbone, Paolo

    2017-01-01

    Novel robot technologies are becoming available to automate more complex tasks, more flexibly, and collaborating with humans. Methods and tools are needed in the automation and robotics industry to develop and integrate this new breed of robotic systems. In this paper, the ISE&PPOOA

  11. Using Five Stage Model to Design of Collaborative Learning Environments in Second Life

    Science.gov (United States)

    Orhan, Sevil; Karaman, M. Kemal

    2014-01-01

    Specifically Second Life (SL) among virtual worlds draws attention of researchers to form collaborative learning environments (Sutcliffe & Alrayes, 2012) since it could be used as a rich platform to simulate a real environment containing many collaborative learning characteristics and interaction tools within itself. Five Stage Model (FSM)…

  12. The Application of Collaborative Business Intelligence Technology in the Hospital SPD Logistics Management Model

    Science.gov (United States)

    LIU, Tongzhu; SHEN, Aizong; HU, Xiaojian; TONG, Guixian; GU, Wei

    2017-01-01

    Background: We aimed to apply collaborative business intelligence (BI) system to hospital supply, processing and distribution (SPD) logistics management model. Methods: We searched Engineering Village database, China National Knowledge Infrastructure (CNKI) and Google for articles (Published from 2011 to 2016), books, Web pages, etc., to understand SPD and BI related theories and recent research status. For the application of collaborative BI technology in the hospital SPD logistics management model, we realized this by leveraging data mining techniques to discover knowledge from complex data and collaborative techniques to improve the theories of business process. Results: For the application of BI system, we: (i) proposed a layered structure of collaborative BI system for intelligent management in hospital logistics; (ii) built data warehouse for the collaborative BI system; (iii) improved data mining techniques such as supporting vector machines (SVM) and swarm intelligence firefly algorithm to solve key problems in hospital logistics collaborative BI system; (iv) researched the collaborative techniques oriented to data and business process optimization to improve the business processes of hospital logistics management. Conclusion: Proper combination of SPD model and BI system will improve the management of logistics in the hospitals. The successful implementation of the study requires: (i) to innovate and improve the traditional SPD model and make appropriate implement plans and schedules for the application of BI system according to the actual situations of hospitals; (ii) the collaborative participation of internal departments in hospital including the department of information, logistics, nursing, medical and financial; (iii) timely response of external suppliers. PMID:28828316

  13. The Application of Collaborative Business Intelligence Technology in the Hospital SPD Logistics Management Model.

    Science.gov (United States)

    Liu, Tongzhu; Shen, Aizong; Hu, Xiaojian; Tong, Guixian; Gu, Wei

    2017-06-01

    We aimed to apply collaborative business intelligence (BI) system to hospital supply, processing and distribution (SPD) logistics management model. We searched Engineering Village database, China National Knowledge Infrastructure (CNKI) and Google for articles (Published from 2011 to 2016), books, Web pages, etc., to understand SPD and BI related theories and recent research status. For the application of collaborative BI technology in the hospital SPD logistics management model, we realized this by leveraging data mining techniques to discover knowledge from complex data and collaborative techniques to improve the theories of business process. For the application of BI system, we: (i) proposed a layered structure of collaborative BI system for intelligent management in hospital logistics; (ii) built data warehouse for the collaborative BI system; (iii) improved data mining techniques such as supporting vector machines (SVM) and swarm intelligence firefly algorithm to solve key problems in hospital logistics collaborative BI system; (iv) researched the collaborative techniques oriented to data and business process optimization to improve the business processes of hospital logistics management. Proper combination of SPD model and BI system will improve the management of logistics in the hospitals. The successful implementation of the study requires: (i) to innovate and improve the traditional SPD model and make appropriate implement plans and schedules for the application of BI system according to the actual situations of hospitals; (ii) the collaborative participation of internal departments in hospital including the department of information, logistics, nursing, medical and financial; (iii) timely response of external suppliers.

  14. University-Industry Research Collaboration: A Model to Assess University Capability

    Science.gov (United States)

    Abramo, Giovanni; D'Angelo, Ciriaco Andrea; Di Costa, Flavia

    2011-01-01

    Scholars and policy makers recognize that collaboration between industry and the public research institutions is a necessity for innovation and national economic development. This work presents an econometric model which expresses the university capability for collaboration with industry as a function of size, location and research quality. The…

  15. Collaboration by design - on the use of value modeling in social innovation projects

    NARCIS (Netherlands)

    Weigand, H.

    2012-01-01

    Nowadays, many innovation projects are based on the collaboration of multiple parties to cocreate value. Unfortunately, the collaboration is not always without problems, not the least when financial and legal concerns come into the picture. Value modeling approaches such as e3-value have proven to

  16. The Co-Creation-Wheel: A Four-Dimensional Model of Collaborative Interorganistional Innovation

    Science.gov (United States)

    Ehlen, Corry; van der Klink, Marcel; Stoffers, Jol; Boshuizen, Henny

    2017-01-01

    Purpose: This study aims to design and validate a conceptual and practical model of co-creation. Co-creation, to design collaborative new products, services and processes in contact with users, has become more and more important because organisations increasingly require multidisciplinary collaboration inside and outside the organisation to…

  17. Developing Custom Fire Behavior Fuel Models for Mediterranean Wildland-Urban Interfaces in Southern Italy

    Science.gov (United States)

    Elia, Mario; Lafortezza, Raffaele; Lovreglio, Raffaella; Sanesi, Giovanni

    2015-09-01

    The dramatic increase of fire hazard in wildland-urban interfaces (WUIs) has required more detailed fuel management programs to preserve ecosystem functions and human settlements. Designing effective fuel treatment strategies allows to achieve goals such as resilient landscapes, fire-adapted communities, and ecosystem response. Therefore, obtaining background information on forest fuel parameters and fuel accumulation patterns has become an important first step in planning fuel management interventions. Site-specific fuel inventory data enhance the accuracy of fuel management planning and help forest managers in fuel management decision-making. We have customized four fuel models for WUIs in southern Italy, starting from forest classes of land-cover use and adopting a hierarchical clustering approach. Furthermore, we provide a prediction of the potential fire behavior of our customized fuel models using FlamMap 5 under different weather conditions. The results suggest that fuel model IIIP (Mediterranean maquis) has the most severe fire potential for the 95th percentile weather conditions and the least severe potential fire behavior for the 85th percentile weather conditions. This study shows that it is possible to create customized fuel models directly from fuel inventory data. This achievement has broad implications for land managers, particularly forest managers of the Mediterranean landscape, an ecosystem that is susceptible not only to wildfires but also to the increasing human population and man-made infrastructures.

  18. Developing Custom Fire Behavior Fuel Models for Mediterranean Wildland-Urban Interfaces in Southern Italy.

    Science.gov (United States)

    Elia, Mario; Lafortezza, Raffaele; Lovreglio, Raffaella; Sanesi, Giovanni

    2015-09-01

    The dramatic increase of fire hazard in wildland-urban interfaces (WUIs) has required more detailed fuel management programs to preserve ecosystem functions and human settlements. Designing effective fuel treatment strategies allows to achieve goals such as resilient landscapes, fire-adapted communities, and ecosystem response. Therefore, obtaining background information on forest fuel parameters and fuel accumulation patterns has become an important first step in planning fuel management interventions. Site-specific fuel inventory data enhance the accuracy of fuel management planning and help forest managers in fuel management decision-making. We have customized four fuel models for WUIs in southern Italy, starting from forest classes of land-cover use and adopting a hierarchical clustering approach. Furthermore, we provide a prediction of the potential fire behavior of our customized fuel models using FlamMap 5 under different weather conditions. The results suggest that fuel model IIIP (Mediterranean maquis) has the most severe fire potential for the 95th percentile weather conditions and the least severe potential fire behavior for the 85th percentile weather conditions. This study shows that it is possible to create customized fuel models directly from fuel inventory data. This achievement has broad implications for land managers, particularly forest managers of the Mediterranean landscape, an ecosystem that is susceptible not only to wildfires but also to the increasing human population and man-made infrastructures.

  19. Numerical modelling of a straw-fired grate boiler

    DEFF Research Database (Denmark)

    Kær, Søren Knudsen

    2004-01-01

    The paper presents a computational fluid dynamics (CFD) analysis of a 33 MW straw-fired grate boiler. Combustion on the grate plays akey-role in the analysis of these boilers and in this work a stand-alone code was used to provide inlet conditions for the CFD analysis. Modelpredictions were...... compared with available gas temperature and species concentration measurements showing good agreement. Combustionof biomass in grate-based boilers is often associated with high emission levels and relatively high amounts of unburnt carbon in the fly ash.Based on the CFD analysis, it is suggested that poor...

  20. PV Performance Modeling Methods and Practices: Results from the 4th PV Performance Modeling Collaborative Workshop.

    Energy Technology Data Exchange (ETDEWEB)

    Stein, Joshua [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-03-01

    In 2014, the IEA PVPS Task 13 added the PVPMC as a formal activity to its technical work plan for 2014-2017. The goal of this activity is to expand the reach of the PVPMC to a broader international audience and help to reduce PV performance modeling uncertainties worldwide. One of the main deliverables of this activity is to host one or more PVPMC workshops outside the US to foster more international participation within this collaborative group. This report reviews the results of the first in a series of these joint IEA PVPS Task 13/PVPMC workshops. The 4th PV Performance Modeling Collaborative Workshop was held in Cologne, Germany at the headquarters of TÜV Rheinland on October 22-23, 2015.

  1. Bayesian nonparametric modeling for comparison of single-neuron firing intensities.

    Science.gov (United States)

    Kottas, Athanasios; Behseta, Sam

    2010-03-01

    We propose a fully inferential model-based approach to the problem of comparing the firing patterns of a neuron recorded under two distinct experimental conditions. The methodology is based on nonhomogeneous Poisson process models for the firing times of each condition with flexible nonparametric mixture prior models for the corresponding intensity functions. We demonstrate posterior inferences from a global analysis, which may be used to compare the two conditions over the entire experimental time window, as well as from a pointwise analysis at selected time points to detect local deviations of firing patterns from one condition to another. We apply our method on two neurons recorded from the primary motor cortex area of a monkey's brain while performing a sequence of reaching tasks.

  2. Integrated production-distribution planning optimization models: A review in collaborative networks context

    Directory of Open Access Journals (Sweden)

    Beatriz Andres

    2017-01-01

    Full Text Available Researchers in the area of collaborative networks are more and more aware of proposing collaborative approaches to address planning processes, due to the advantages associated when enterprises perform integrated planning models. Collaborative production-distribution planning, among the supply network actors, is considered a proper mechanism to support enterprises on dealing with uncertainties and dynamicity associated to the current markets. Enterprises, and especially SMEs, should be able to overcome the continuous changes of the market by increasing their agility. Carrying out collaborative planning allows enterprises to enhance their readiness and agility for facing the market turbulences. However, SMEs have limited access when incorporating optimization tools to deal with collaborative planning, reducing their ability to respond to the competition. The problem to solve is to provide SMEs affordable solutions to support collaborative planning. In this regard, new optimisation algorithms are required in order to improve the collaboration within the supply network partners. As part of the H2020 Cloud Collaborative Manufacturing Networks (C2NET research project, this paper presents a study on integrated production and distribution plans. The main objective of the research is to identify gaps in current optimization models, proposed to address integrated planning, taking into account the requirements and needs of the industry. Thus, the needs of the companies belonging to the industrial pilots, defined in the C2NET project, are identified; analysing how these needs are covered by the optimization models proposed in the literature, to deal with the integrated production-distribution planning.

  3. Physical characteristics of shrub and conifer fuels for fire behavior models

    Science.gov (United States)

    Jonathan R. Gallacher; Thomas H. Fletcher; Victoria Lansinger; Sydney Hansen; Taylor Ellsworth; David R. Weise

    2017-01-01

    The physical properties and dimensions of foliage are necessary inputs for some fire spread models. Currently, almost no data exist on these plant characteristics to fill this need. In this report, we measured the physical properties and dimensions of the foliage from 10 live shrub and conifer fuels throughout a 1-year period. We developed models to predict relative...

  4. BEHAVE: fire behavior prediction and fuel modeling system--FUEL subsystem

    Science.gov (United States)

    Robert E. Burgan; Richard C. Rothermel

    1984-01-01

    This manual documents the fuel modeling procedures of BEHAVE--a state-of-the-art wildland fire behavior prediction system. Described are procedures for collecting fuel data, using the data with the program, and testing and adjusting the fuel model.

  5. Modelling dune erosion, overwash and breaching at Fire Island (NY) during hurricane Sandy

    NARCIS (Netherlands)

    De Vet, P.L.M.; McCall, R.T.; Den Bieman, J.P.; Stive, M.J.F.; Van Ormondt, M.

    2015-01-01

    In 2012, Hurricane Sandy caused a breach at Fire Island (NY, USA), near Pelican Island. This paper aims at modelling dune erosion, overwash and breaching processes that occured during the hurricane event at this stretch of coast with the numerical model XBeach. By using the default settings, the

  6. Comparing fire spread algorithms using equivalence testing and neutral landscape models

    Science.gov (United States)

    Brian R. Miranda; Brian R. Sturtevant; Jian Yang; Eric J. Gustafson

    2009-01-01

    We demonstrate a method to evaluate the degree to which a meta-model approximates spatial disturbance processes represented by a more detailed model across a range of landscape conditions, using neutral landscapes and equivalence testing. We illustrate this approach by comparing burn patterns produced by a relatively simple fire spread algorithm with those generated by...

  7. Collaborative Modeling: Experience of the U.S. Preventive Services Task Force.

    Science.gov (United States)

    Petitti, Diana B; Lin, Jennifer S; Owens, Douglas K; Croswell, Jennifer M; Feuer, Eric J

    2018-01-01

    Models can be valuable tools to address uncertainty, trade-offs, and preferences when trying to understand the effects of interventions. Availability of results from two or more independently developed models that examine the same question (comparative modeling) allows systematic exploration of differences between models and the effect of these differences on model findings. Guideline groups sometimes commission comparative modeling to support their recommendation process. In this commissioned collaborative modeling, modelers work with the people who are developing a recommendation or policy not only to define the questions to be addressed but ideally, work side-by-side with each other and with systematic reviewers to standardize selected inputs and incorporate selected common assumptions. This paper describes the use of commissioned collaborative modeling by the U.S. Preventive Services Task Force (USPSTF), highlighting the general challenges and opportunities encountered and specific challenges for some topics. It delineates other approaches to use modeling to support evidence-based recommendations and the many strengths of collaborative modeling compared with other approaches. Unlike systematic reviews prepared for the USPSTF, the commissioned collaborative modeling reports used by the USPSTF in making recommendations about screening have not been required to follow a common format, sometimes making it challenging to understand key model features. This paper presents a checklist developed to critically appraise commissioned collaborative modeling reports about cancer screening topics prepared for the USPSTF. Copyright © 2017 American Journal of Preventive Medicine. All rights reserved.

  8. Fire science at LLNL: A review

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, H.K. (ed.)

    1990-03-01

    This fire sciences report from LLNL includes topics on: fire spread in trailer complexes, properties of welding blankets, validation of sprinkler systems, fire and smoke detectors, fire modeling, and other fire engineering and safety issues. (JEF)

  9. Quantifications and Modeling of Human Failure Events in a Fire PSA

    International Nuclear Information System (INIS)

    Kang, Dae Il; Kim, Kilyoo; Jang, Seung-Cheol

    2014-01-01

    USNRC and EPRI developed guidance, 'Fire Human Reliability Analysis Guidelines, NUREG-1921', for estimating human error probabilities (HEPs) for HFEs under fire conditions. NUREG-1921 classifies HFEs into four types associated with the following human actions: - Type 1: New and existing Main Control Room (MCR) actions - Type 2: New and existing ex-MCR actions - Type 3: Actions associated with using alternate shutdown means (ASD) - Type 4: Actions relating to the error of commissions (EOCs) or error of omissions (EOOs) as a result of incorrect indications (SPI) In this paper, approaches for the quantifications and modeling of HFEs related to Type 1, 2 and 3 human actions are introduced. This paper introduced the human reliability analysis process for a fire PSA of Hanul Unit 3. A multiplier of 10 was used to re-estimate the HEPs for the preexisting internal human actions. The HEPs for all ex- MCR actions were assumed to be one. New MCR human actions were quantified using the scoping analysis method of NUREG-1921. If the quantified human action were identified to be risk-significant, detailed approaches (modeling and quantification) were used for incorporating fire situations into them. Multiple HFEs for single human action were defined and they were separately and were separately quantified to incorporate the specific fire situations into them. From this study, we can confirm that the modeling as well as quantifications of human actions is very important to appropriately treat them in PSA logic structures

  10. Quantifications and Modeling of Human Failure Events in a Fire PSA

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Dae Il; Kim, Kilyoo; Jang, Seung-Cheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    USNRC and EPRI developed guidance, 'Fire Human Reliability Analysis Guidelines, NUREG-1921', for estimating human error probabilities (HEPs) for HFEs under fire conditions. NUREG-1921 classifies HFEs into four types associated with the following human actions: - Type 1: New and existing Main Control Room (MCR) actions - Type 2: New and existing ex-MCR actions - Type 3: Actions associated with using alternate shutdown means (ASD) - Type 4: Actions relating to the error of commissions (EOCs) or error of omissions (EOOs) as a result of incorrect indications (SPI) In this paper, approaches for the quantifications and modeling of HFEs related to Type 1, 2 and 3 human actions are introduced. This paper introduced the human reliability analysis process for a fire PSA of Hanul Unit 3. A multiplier of 10 was used to re-estimate the HEPs for the preexisting internal human actions. The HEPs for all ex- MCR actions were assumed to be one. New MCR human actions were quantified using the scoping analysis method of NUREG-1921. If the quantified human action were identified to be risk-significant, detailed approaches (modeling and quantification) were used for incorporating fire situations into them. Multiple HFEs for single human action were defined and they were separately and were separately quantified to incorporate the specific fire situations into them. From this study, we can confirm that the modeling as well as quantifications of human actions is very important to appropriately treat them in PSA logic structures.

  11. Modeling of Electrical Cable Failure in a Dynamic Assessment of Fire Risk

    Science.gov (United States)

    Bucknor, Matthew D.

    Fires at a nuclear power plant are a safety concern because of their potential to defeat the redundant safety features that provide a high level of assurance of the ability to safely shutdown the plant. One of the added complexities of providing protection against fires is the need to determine the likelihood of electrical cable failure which can lead to the loss of the ability to control or spurious actuation of equipment that is required for safe shutdown. A number of plants are now transitioning from their deterministic fire protection programs to a risk-informed, performance based fire protection program according to the requirements of National Fire Protection Association (NFPA) 805. Within a risk-informed framework, credit can be taken for the analysis of fire progression within a fire zone that was not permissible within the deterministic framework of a 10 CFR 50.48 Appendix R safe shutdown analysis. To perform the analyses required for the transition, plants need to be able to demonstrate with some level of assurance that cables related to safe shutdown equipment will not be compromised during postulated fire scenarios. This research contains the development of new cable failure models that have the potential to more accurately predict electrical cable failure in common cable bundle configurations. Methods to determine the thermal properties of the new models from empirical data are presented along with comparisons between the new models and existing techniques used in the nuclear industry today. A Dynamic Event Tree (DET) methodology is also presented which allows for the proper treatment of uncertainties associated with fire brigade intervention and its effects on cable failure analysis. Finally a shielding analysis is performed to determine the effects on the temperature response of a cable bundle that is shielded from a fire source by an intervening object such as another cable tray. The results from the analyses demonstrate that models of similar

  12. Assessment of crown fire initiation and spread models in Mediterranean conifer forests by using data from field and laboratory experiments

    Energy Technology Data Exchange (ETDEWEB)

    Rodríguez y Silva, F.; Guijarro, M.; Madrigal, J.; Jiménez, E.; Molina, J.R.; Hernando, C.; Vélez, R.; Vega, J.A.

    2017-11-01

    Aims of study: To conduct the first full-scale crown fire experiment carried out in a Mediterranean conifer stand in Spain; to use different data sources to assess crown fire initiation and spread models, and to evaluate the role of convection in crown fire initiation. Area of study: The Sierra Morena mountains (Coordinates ETRS89 30N: X: 284793-285038; Y: 4218650-4218766), southern Spain, and the outdoor facilities of the Lourizán Forest Research Centre, northwestern Spain. Material and methods: The full-scale crown fire experiment was conducted in a young Pinus pinea stand. Field data were compared with data predicted using the most used crown fire spread models. A small-scale experiment was developed with Pinus pinaster trees to evaluate the role of convection in crown fire initiation. Mass loss calorimeter tests were conducted with P. pinea needles to estimate residence time of the flame, which was used to validate the crown fire spread model. Main results: The commonly used crown fire models underestimated the crown fire spread rate observed in the full-scale experiment, but the proposed new integrated approach yielded better fits. Without wind-forced convection, tree crowns did not ignite until flames from an intense surface fire contacted tree foliage. Bench-scale tests based on radiation heat flux therefore offer a limited insight to full-scale phenomena. Research highlights: Existing crown fire behaviour models may underestimate the rate of spread of crown fires in many Mediterranean ecosystems. New bench-scale methods based on flame buoyancy and more crown field experiments allowing detailed measurements of fire behaviour are needed.

  13. Assessment of crown fire initiation and spread models in Mediterranean conifer forests by using data from field and laboratory experiments

    International Nuclear Information System (INIS)

    Rodríguez y Silva, F.; Guijarro, M.; Madrigal, J.; Jiménez, E.; Molina, J.R.; Hernando, C.; Vélez, R.; Vega, J.A.

    2017-01-01

    Aims of study: To conduct the first full-scale crown fire experiment carried out in a Mediterranean conifer stand in Spain; to use different data sources to assess crown fire initiation and spread models, and to evaluate the role of convection in crown fire initiation. Area of study: The Sierra Morena mountains (Coordinates ETRS89 30N: X: 284793-285038; Y: 4218650-4218766), southern Spain, and the outdoor facilities of the Lourizán Forest Research Centre, northwestern Spain. Material and methods: The full-scale crown fire experiment was conducted in a young Pinus pinea stand. Field data were compared with data predicted using the most used crown fire spread models. A small-scale experiment was developed with Pinus pinaster trees to evaluate the role of convection in crown fire initiation. Mass loss calorimeter tests were conducted with P. pinea needles to estimate residence time of the flame, which was used to validate the crown fire spread model. Main results: The commonly used crown fire models underestimated the crown fire spread rate observed in the full-scale experiment, but the proposed new integrated approach yielded better fits. Without wind-forced convection, tree crowns did not ignite until flames from an intense surface fire contacted tree foliage. Bench-scale tests based on radiation heat flux therefore offer a limited insight to full-scale phenomena. Research highlights: Existing crown fire behaviour models may underestimate the rate of spread of crown fires in many Mediterranean ecosystems. New bench-scale methods based on flame buoyancy and more crown field experiments allowing detailed measurements of fire behaviour are needed.

  14. Web-Based Modelling and Collaborative Simulation of Declarative Processes

    DEFF Research Database (Denmark)

    Slaats, Tijs; Marquard, Morten; Shahzad, Muhammad

    2015-01-01

    -user discussions on how knowledge workers really work, by enabling collaborative simulation of processes. In earlier work we reported on the integration of DCR Graphs as a workflow execution formalism in the existing Exformatics ECM products. In this paper we report on the advances we have made over the last two......As a provider of Electronic Case Management solutions to knowledge-intensive businesses and organizations, the Danish company Exformatics has in recent years identified a need for flexible process support in the tools that we provide to our customers. We have addressed this need by adapting DCR...... Graphs, a formal declarative workflow notation developed at the IT University of Copenhagen. Through close collaboration with academia we first integrated execution support for the notation into our existing tools, by leveraging a cloud-based process engine implementing the DCR formalism. Over the last...

  15. Collaborative autonomous systems in models of urban logistics

    OpenAIRE

    Arango Serna, Martín Darío; Serna Uran, Conrado Augusto; Alvarez Uribe, Karla Cristina; Arango Serna, Martín Darío

    2012-01-01

    Cities growth and along with them the exchange and distribution of goods and services has led in recent years to a greater increasing interest for the optimization of logistic processes carried out in urban areas. In this article, the main approaches and solutions which have been proposed from academic research will be described, focusing mainly on collaborative autonomic logistics, which is offered as an attractive solution to the urban goods distribution problems in complex cities.

  16. Collaborative Networks Model for Clothing and Footwear Business Sector

    OpenAIRE

    Bastos , João; Franchini , Valentina; Azevedo , Américo; Fornasiero , Rosanna

    2012-01-01

    Part 12: Collaboration in Traditional Sectors; International audience; In clothing and footwear business sector, consumer needs and expectations of specific target groups - such as elderly, obese, disabled, or diabetic persons - are arising as challenging opportunities for European companies that are asked to supply small series of innovative and fashionable goods of high quality, affordable price and eco-compatible. This paper aims at propose a three level (strategic, tactical, and operation...

  17. Using a prescribed fire to test custom and standard fuel models for fire behaviour prediction in a non-native, grass-invaded tropical dry shrubland

    Science.gov (United States)

    Andrew D. Pierce; Sierra McDaniel; Mark Wasser; Alison Ainsworth; Creighton M. Litton; Christian P. Giardina; Susan Cordell; Ralf Ohlemuller

    2014-01-01

    Questions: Do fuel models developed for North American fuel types accurately represent fuel beds found in grass-invaded tropical shrublands? Do standard or custom fuel models for firebehavior models with in situ or RAWS measured fuel moistures affect the accuracy of predicted fire behavior in grass-invaded tropical shrublands? Location: Hawai’i Volcanoes National...

  18. Collaborative Economy

    DEFF Research Database (Denmark)

    collaborative economy and tourism Dianne Dredge and Szilvia Gyimóthy PART I - Theoretical explorations 2.Definitions and mapping the landscape in the collaborative economy Szilvia Gyimóthy and Dianne Dredge 3.Business models of the collaborative economy Szilvia Gyimóthy 4.Responsibility and care...... in the collaborative economy Dianne Dredge 5.Networked cultures in the collaborative economy Szilvia Gyimóthy 6.Policy and regulatory perspectives in the collaborative economy Dianne Dredge PART II - Disruptions, innovations and transformations 7.Regulating innovation in the collaborative economy: An examination...... localities of tourism Greg Richards 11.Collaborative economy and destination marketing organizations: A systems approach Jonathan Day 12.Working within the Collaborative Tourist Economy: The complex crafting of work and meaning Jane Widtfeldt Meged and Mathilde Dissing Christensen PART - III Encounters...

  19. Advanced char burnout models for the simulation of pulverized coal fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    T. Severin; S. Wirtz; V. Scherer [Ruhr-University, Bochum (Germany). Institute of Energy Plant Technology (LEAT)

    2005-07-01

    The numerical simulation of coal combustion processes is widely used as an efficient means to predict burner or system behaviour. In this paper an approach to improve CFD simulations of pulverized coal fired boilers with advanced coal combustion models is presented. In simple coal combustion models, first order Arrhenius rate equations are used for devolatilization and char burnout. The accuracy of such simple models is sufficient for the basic aspects of heat release. The prediction of carbon-in-ash is one aspect of special interest in the simulation of pulverized coal fired boilers. To determine the carbon-in-ash levels in the fly ash of coal fired furnaces, the char burnout model has to be more detailed. It was tested, in how far changing operating conditions affect the carbon-in-ash prediction of the simulation. To run several test cases in a short time, a simplified cellnet model was applied. To use a cellnet model for simulations of pulverized coal fired boilers, it was coupled with a Lagrangian particle model, used in CFD simulations, too. 18 refs., 5 figs., 5 tabs.

  20. The tariff for fire and theft car insurance: analysis with a Cox model

    OpenAIRE

    Bruno Scarpa

    2013-01-01

    In this paper we analyze the problem of identification of a tariff for a Fire & Theft Car policy for Insurance Companies. Usually companies obtain this tariff by empirical estimate of the pure rate by evaluating the impact of some personalization variables. In this paper we propose the usage of a semi-parametric Cox model, where the response variable is not the waiting time until an event, but the degree of damage because of theft or fire of a car. The proposed model allows to easily tackle t...

  1. The tariff for fire and theft car insurance: analysis with a Cox model

    Directory of Open Access Journals (Sweden)

    Bruno Scarpa

    2013-05-01

    Full Text Available In this paper we analyze the problem of identification of a tariff for a Fire & Theft Car policy for Insurance Companies. Usually companies obtain this tariff by empirical estimate of the pure rate by evaluating the impact of some personalization variables. In this paper we propose the usage of a semi-parametric Cox model, where the response variable is not the waiting time until an event, but the degree of damage because of theft or fire of a car. The proposed model allows to easily tackle typical problems in data available to the companies, like the presence of franchises, which are treated as censored data.

  2. Modelling long-term fire occurrence factors in Spain by accounting for local variations with geographically weighted regression

    Science.gov (United States)

    Martínez-Fernández, J.; Chuvieco, E.; Koutsias, N.

    2013-02-01

    Humans are responsible for most forest fires in Europe, but anthropogenic factors behind these events are still poorly understood. We tried to identify the driving factors of human-caused fire occurrence in Spain by applying two different statistical approaches. Firstly, assuming stationary processes for the whole country, we created models based on multiple linear regression and binary logistic regression to find factors associated with fire density and fire presence, respectively. Secondly, we used geographically weighted regression (GWR) to better understand and explore the local and regional variations of those factors behind human-caused fire occurrence. The number of human-caused fires occurring within a 25-yr period (1983-2007) was computed for each of the 7638 Spanish mainland municipalities, creating a binary variable (fire/no fire) to develop logistic models, and a continuous variable (fire density) to build standard linear regression models. A total of 383 657 fires were registered in the study dataset. The binary logistic model, which estimates the probability of having/not having a fire, successfully classified 76.4% of the total observations, while the ordinary least squares (OLS) regression model explained 53% of the variation of the fire density patterns (adjusted R2 = 0.53). Both approaches confirmed, in addition to forest and climatic variables, the importance of variables related with agrarian activities, land abandonment, rural population exodus and developmental processes as underlying factors of fire occurrence. For the GWR approach, the explanatory power of the GW linear model for fire density using an adaptive bandwidth increased from 53% to 67%, while for the GW logistic model the correctly classified observations improved only slightly, from 76.4% to 78.4%, but significantly according to the corrected Akaike Information Criterion (AICc), from 3451.19 to 3321.19. The results from GWR indicated a significant spatial variation in the local

  3. Daily and 3-hourly Variability in Global Fire Emissions and Consequences for Atmospheric Model Predictions of Carbon Monoxide

    Science.gov (United States)

    Mu, M.; Randerson, J. T.; vanderWerf, G. R.; Giglio, L.; Kasibhatla, P.; Morton, D.; Collatz, G. J.; DeFries, R. S.; Hyer, E. J.; Prins, E. M.; hide

    2011-01-01

    Attribution of the causes of atmospheric trace gas and aerosol variability often requires the use of high resolution time series of anthropogenic and natural emissions inventories. Here we developed an approach for representing synoptic- and diurnal-scale temporal variability in fire emissions for the Global Fire Emissions Database version 3 (GFED3). We disaggregated monthly GFED3 emissions during 2003.2009 to a daily time step using Moderate Resolution Imaging Spectroradiometer (MODIS) ]derived measurements of active fires from Terra and Aqua satellites. In parallel, mean diurnal cycles were constructed from Geostationary Operational Environmental Satellite (GOES) Wildfire Automated Biomass Burning Algorithm (WF_ABBA) active fire observations. Daily variability in fires varied considerably across different biomes, with short but intense periods of daily emissions in boreal ecosystems and lower intensity (but more continuous) periods of burning in savannas. These patterns were consistent with earlier field and modeling work characterizing fire behavior dynamics in different ecosystems. On diurnal timescales, our analysis of the GOES WF_ABBA active fires indicated that fires in savannas, grasslands, and croplands occurred earlier in the day as compared to fires in nearby forests. Comparison with Total Carbon Column Observing Network (TCCON) and Measurements of Pollution in the Troposphere (MOPITT) column CO observations provided evidence that including daily variability in emissions moderately improved atmospheric model simulations, particularly during the fire season and near regions with high levels of biomass burning. The high temporal resolution estimates of fire emissions developed here may ultimately reduce uncertainties related to fire contributions to atmospheric trace gases and aerosols. Important future directions include reconciling top ]down and bottom up estimates of fire radiative power and integrating burned area and active fire time series from

  4. A model of collaboration between nursing education institutions in the North West Province of South Africa

    Directory of Open Access Journals (Sweden)

    Kathleen K. Direko

    2017-09-01

    Conclusion: A model of collaboration was acceptable to the majority of nurse education stakeholders. Other implications are that there was a need for the improvement of scholarship among nurse educators and clinical mentors, sharing rare skills, and addressing perceived challenges.

  5. Ecological modeling of pollutants in accidental fire at the landfill waste

    Directory of Open Access Journals (Sweden)

    Stefanov Sonja B.

    2013-01-01

    Full Text Available Paper presents tyre as flammable material and some examples of tyre fires in the world. Uncontrolled tyre fires produce a lot of smoke and air pollutants, including benzene and polycyclic aromatic hydrocarbons (PAH. Great heat leads to the generation of pyrolytic oil which, when mixed with the fire extinguishing agent, contaminates the surrounding soil, surface water and underground water. Paper analyzes and presents in particular the emission factors of incomplete burning of waste car tyres. Metal dust emissions have been presented, volatile organic compund (VOC emissions, slightly volatile organic compound (SVOC emissions and emissions of polycyclic aromatic hydrocarbons (PAH. Evaluation of the effect on the air quality has been graphically presented by modelling of uncotrolled tyre burning by using EPA "SCREEN 3 MODEL".

  6. Improved modelling of sodium-spray fires and sodium-combustion aerosol chemical evolution - 15488

    International Nuclear Information System (INIS)

    Mathe, E.; Kissane, M.; Petitprez, D.

    2015-01-01

    In the context of the Generation IV Initiative, the consequences of a severe-accident in sodium-cooled fast reactor (SFR) must be studied. Being pyrophoric, sodium will burn upon contact with air in a containment creating toxic aerosols and we must take into account these fire aerosols when assessing the source term. We have developed a numerical simulation named NATRAC to calculate the mass of aerosols produced during a spray fire in a SFR severe accident. The results show that the mass of oxide aerosols can involve more than 60% of the ejected sodium. In a second part we have developed a numerical simulation named STARK based on the Cooper model that models the physico-chemical transformations of the aerosols. However, this model has never been validated and the literature does not permit to do so. In these conditions, we have designed and performed our own experiment ESSTIA to obtain the missing values of the parameters that govern Cooper model. The modified Cooper model we propose with the new parameters reproduces correctly the ESSTIA experimental data. The only parameter that has not yet been measured is the tortuosity of the sodium-fire aerosols surface layers. A dedicated experiment using real sodium-fire aerosols could eliminate any doubts about the uncertainty of the proposed Cooper model

  7. Fire exposed facades: Numerical modelling of the LEPIR2 testing facility

    Directory of Open Access Journals (Sweden)

    Dréan Virginie

    2016-01-01

    Full Text Available LEPIR2 testing facility is aimed to evaluate the fire behaviour of construction solutions implemented on facade according with the experimental evaluation required by the French Technical Specification 249 (IT249 of the safety regulation. It aims to limit the risks of fire spreading by facades to upper levels. This facility involves a wood crib fire in the lower compartment of a full scale two levels high structure. Flames are coming outside from the compartment through windows openings and develop in front of the facade. Computational fluids dynamics simulations are carried out with the FDS code (Fire Dynamics Simulator for two full-scale experiments performed by Efectis France laboratory. The first objective of this study is to evaluate the ability of numerical model to reproduce quantitative results in terms of gas temperatures and heat flux on the tested facade for further evaluation of fire performances of an insulation solution. When experimental results are compared with numerical calculations, good agreement is found out for every quantities and each test. The proposed models for wood cribs and geometry give correct thermal loads and flames shape near the tested facade.

  8. Future Projections of Fire Occurrence in Brazil Using EC-Earth Climate Model

    Directory of Open Access Journals (Sweden)

    Patrícia Silva

    Full Text Available Abstract Fire has a fundamental role in the Earth system as it influences global and local ecosystem patterns and processes, such as vegetation distribution and structure, the carbon cycle and climate. Since, in the global context, Brazil is one of the regions with higher fire activity, an assessment is here performed of the sensitivity of the wildfire regime in Brazilian savanna and shrubland areas to changes in regional climate during the 21st Century, for an intermediate scenario (RCP4.5 of climate change. The assessment is based on a spatial and temporal analysis of a meteorological fire danger index specifically developed for Brazilian biomes, which was evaluated based on regional climate simulations of temperature, relative humidity and precipitation using the Rossby Centre Regional Climate Model (RCA4 forced by the EC-Earth earth system model. Results show a systematic increase in the extreme levels of fire danger throughout the 21st Century that mainly results from the increase in maximum daily temperature, which rises by about 2 °C between 2005 and 2100. This study provides new insights about projected fire activity in Brazilian woody savannas associated to climate change and is expected to benefit the user community, from governmental policies to land management and climate researches.

  9. Large, high-intensity fire events in Southern California shrublands: Debunking the fine-grain age patch model

    Science.gov (United States)

    Keeley, J.E.; Zedler, P.H.

    2009-01-01

    We evaluate the fine-grain age patch model of fire regimes in southern California shrublands. Proponents contend that the historical condition was characterized by frequent small to moderate size, slow-moving smoldering fires, and that this regime has been disrupted by fire suppression activities that have caused unnatural fuel accumulation and anomalously large and catastrophic wildfires. A review of more than 100 19th-century newspaper reports reveals that large, high-intensity wildfires predate modern fire suppression policy, and extensive newspaper coverage plus first-hand accounts support the conclusion that the 1889 Santiago Canyon Fire was the largest fire in California history. Proponents of the fine-grain age patch model contend that even the very earliest 20th-century fires were the result of fire suppression disrupting natural fuel structure. We tested that hypothesis and found that, within the fire perimeters of two of the largest early fire events in 1919 and 1932, prior fire suppression activities were insufficient to have altered the natural fuel structure. Over the last 130 years there has been no significant change in the incidence of large fires greater than 10000 ha, consistent with the conclusion that fire suppression activities are not the cause of these fire events. Eight megafires (???50 000 ha) are recorded for the region, and half have occurred in the last five years. These burned through a mosaic of age classes, which raises doubts that accumulation of old age classes explains these events. Extreme drought is a plausible explanation for this recent rash of such events, and it is hypothesized that these are due to droughts that led to increased dead fine fuels that promoted the incidence of firebrands and spot fires. A major shortcoming of the fine-grain age patch model is that it requires age-dependent flammability of shrubland fuels, but seral stage chaparral is dominated by short-lived species that create a dense surface layer of fine

  10. Fire Hydrants, Both public and private fire hydrants in Johnson County. Spring Hill is hte only entity missing. Data is limited to CUE (Collaborative Utiity Exchange) Participants and subcontractors of them., Published in 2004, Johnson County Government.

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Fire Hydrants dataset current as of 2004. Both public and private fire hydrants in Johnson County. Spring Hill is hte only entity missing. Data is limited to CUE...

  11. Collaborative Research and Development (CR&D). Task Order 0049: Tribological Modeling

    Science.gov (United States)

    2008-05-01

    scratch test for TiN on stainless steel with better substrate mechanical properties. This present study was focused on the study of stress distribution...AFRL-RX-WP-TR-2010-4189 COLLABORATIVE RESEARCH AND DEVELOPMENT (CR&D) Task Order 0049: Tribological Modeling Young Sup Kang Universal...SUBTITLE COLLABORATIVE RESEARCH AND DEVELOPMENT (CR&D) Task Order 0049: Tribological Modeling 5a. CONTRACT NUMBER F33615-03-D-5801-0049 5b

  12. Photochemical model estimated fire impacts on ozone and aerosol evaluated with field studies and routine data sources

    Science.gov (United States)

    Baker, K. R.

    2017-12-01

    Highly instrumented field studies provide a unique opportunity to evaluate multiple aspects of photochemical grid model representation of fire emissions, dispersion, and chemical evolution. Fuel information and burn area for a specific fire coupled with near-fire and downwind chemical measurements provides information needed to constrain model predicted fire plume transport and chemical evolution of important pollutants such as ozone and particulate matter (PM2.5) that have deleterious health effects. Most local to regional scale field campaigns to date have made relatively few transects through plumes from fires with well characterized fuel type and consumption. While more comprehensive field studies are being planned for 2018 and beyond (WE-CAN, FIREX, FIRE-CHEM, and FASMEE), existing measurement data from multiple field campaigns including 2013 SEAC4RS, satellite data, and routine surface networks are used to assess how a regulatory modeling system captures fire impacts on local to regional scale ozone and PM2.5. Key aspects of the regulatory modeling system include fire location and burn area from SMARTFIRE2, emissions from BlueSky framework, and predictions of ambient O3 and PM2.5 from the Community Multiscale Air Quality (CMAQ) photochemical transport model. A comparison of model estimated O3 from specific fires with routine surface measurements at rural locations in proximity to the 2013 Rim fire, 2011 Wallow fire, and 2011 Flint Hills fires suggest the modeling system over-estimates smoke impacts on hourly ozone. Sensitivity simulations where solar radiation and photolysis rates are more aggressively attenuated by smoke reduced O3 predictions but did not ameliorate the over prediction bias. PM2.5 organic carbon tends to be overpredicted at rural surface sites downwind from the 2011 Flint Hills prescribed fires while results were mixed at rural sites downwind of the 2013 Rim fire and 2011 Wallow fire suggesting differences in fuel characterization (e

  13. Online Course Model that Fosters Interdisciplinary Collaboration Among Graduate Students

    Science.gov (United States)

    deCharon, A.; Repa, J. T.; Companion, C. J.; Taylor, L.

    2016-02-01

    First piloted in Fall 2014, "Broaden the Impacts of Your Research" is a fully asynchronous (i.e., no live or scheduled sessions) online graduate course. This two-credit offering was designed in response to evaluation data from 73 graduate students who participated in four National Science Foundation-funded workshops (deCharon et al., 2013). As a community of practice, students from various scientific disciplines learn about communication and collaboration skills, practice these skills by developing a portfolio of products, and provide feedback on their classmates' products. The course is organized into four sections during the 14-week semester, each with its own set of objectives including: assessing and reducing jargon; engaging in interdisciplinary collaboration; understanding non-scientist audiences' needs; and deconstructing science and connecting to society. The course's quality was assessed through a review of its design by an external evaluator who also gauged its overall efficacy by comparing students' weekly blog posts with the course's goals and objectives. Effectiveness was also evaluated based on students' data from post-semester surveys. Based on these analyses, it has been determined that the course is most appropriate for students who have conducted their initial research and are preparing to communicate it to others and seek additional funding. It exposes students to communications experts through video guest lectures, and it fosters interdisciplinary online collaboration. Participants benefit from employing a variety of online tools to examine and clarify thinking about their own research. Given that the course is online and 100% asynchronous, it is highly flexible and could potentially serve students worldwide. This presentation will focus on the design of "Broaden the Impacts of Your Research," provide evaluation results from both cohorts (i.e., Fall 2014, Fall 2015), and discuss its transferability to other universities or professional societies.

  14. Identifying and quantifying energy savings on fired plant using low cost modelling techniques

    International Nuclear Information System (INIS)

    Tucker, Robert; Ward, John

    2012-01-01

    Research highlights: → Furnace models based on the zone method for radiation calculation are described. → Validated steady-state and transient models have been developed. → We show how these simple models can identify the best options for saving energy. → High emissivity coatings predicted to give performance enhancement on a fired heater. → Optimal heat recovery strategies on a steel reheating furnace are predicted. -- Abstract: Combustion in fired heaters, boilers and furnaces often accounts for the major energy consumption on industrial processes. Small improvements in efficiency can result in large reductions in energy consumption, CO 2 emissions, and operating costs. This paper will describe some useful low cost modelling techniques based on the zone method to help identify energy saving opportunities on high temperature fuel-fired process plant. The zone method has for many decades, been successfully applied to small batch furnaces through to large steel-reheating furnaces, glass tanks, boilers and fired heaters on petrochemical plant. Zone models can simulate both steady-state furnace operation and more complex transient operation typical of a production environment. These models can be used to predict thermal efficiency and performance, and more importantly, to assist in identifying and predicting energy saving opportunities from such measures as: ·Improving air/fuel ratio and temperature controls. ·Improved insulation. ·Use of oxygen or oxygen enrichment. ·Air preheating via flue gas heat recovery. ·Modification to furnace geometry and hearth loading. There is also increasing interest in the application of refractory coatings for increasing surface radiation in fired plant. All of the techniques can yield savings ranging from a few percent upwards and can deliver rapid financial payback, but their evaluation often requires robust and reliable models in order to increase confidence in making financial investment decisions. This paper gives

  15. Evaluation of a Danish pharmacist student-physician medication review collaboration model

    DEFF Research Database (Denmark)

    Kaae, Susanne; Sørensen, Ellen Westh; Nørgaard, Lotte Stig

    2014-01-01

    Background Interprofessional collaboration between pharmacists and physicians to conduct joint home medication reviews (HMR) is important for optimizing the medical treatment of patients suffering from chronic illnesses. However, collaboration has proved difficult to achieve. The HMR programme...... "Medisam" was launched in 2009 at the University of Copenhagen with the aim of "developing, implementing and evaluating a collaboration model for HMRs and medicine reconciliations in Denmark". The Medisam programme involves patients, pharmacy internship students, the (pharmacist) supervisor of the pharmacy...... students and physicians. Objective To explore if it was possible through the Medisam programme to obtain a fruitful HMR collaboration between pharmacy internship students and physicians as a means to develop HMR collaboration between trained pharmacists and physicians further. Setting Ten matching pairs...

  16. Collaborative spatial analysis and modelling in a research environment

    CSIR Research Space (South Africa)

    Naudé, A

    2006-02-01

    Full Text Available in applications not working very well together. Two words in the title of the project hint at the need for interoperability, namely 'collaborative' and 'platform'. They both point to the idea of composition described above – the need to draw... with I.T. “The ability of information systems to operate in conjunction with each other encompassing communication protocols, hardware, software, application, and data compatibility layers.” - www.ichnet.org/glossary.htm “The ability of multiple...

  17. The development of thermal models for a UF6 transport container in a fully engulfing fire

    International Nuclear Information System (INIS)

    Lomas, J.; Clayton, D.G.

    1993-01-01

    This paper describes the recent development work on a lumped-parameter model known as BURST3 created by BNFL to examine the physics of the heating problem. The predictions of this model were compared with the results obtained by Mallett in 1965, in which small (3.5, 5 and 8 inch diameter) cylinders were exposed to a fire. In general, the comparison is good; however there are some differences - particularly on the speed of response of the wall temperature to the heating from the fire. The model was further modified to allow conditions of partial and full insulation to be investigated. The partially insulated condition simulates the Japanese proposal to insulate the ends of the container only, leaving the cylinder bare between the stiffening rings. The results obtained with our modified model support the predictions of Abe et al that the partially-insulated cylinder will survive the fire test. The analysis of a completely insulated container has indicated that a minimal thickness of insulation provides sufficient protection to allow survival in the fire test. A discussion of additional improvements to the lumped-parameter model are presented. (J.P.N.)

  18. Use of a field model to analyze probable fire environments encountered within the complex geometries of nuclear power plants

    International Nuclear Information System (INIS)

    Boccio, J.L.; Usher, J.L.; Singhal, A.K.; Tam, L.T.

    1985-08-01

    A fire in a nuclear power plant (NPP) can damage equipment needed to safely operate the plant and thereby either directly cause an accident or else reduce the plant's margin of safety. The development of a field-model fire code to analyze the probable fire environments encountered within NPP is discussed. A set of fire tests carried out under the aegis of the US Nuclear Regulatory Commission (NRC) is described. The results of these tests are then utilized to validate the field model

  19. Collaboration of Physician, Pharmacist and Director Model Toward the Improvement of Teamwork Effectiveness in Hospital

    Directory of Open Access Journals (Sweden)

    Widy S. Abdulkadir

    2017-09-01

    Full Text Available Collaboration of physicians and pharmacists is very important in providing treatment to patients. Collaboration includes an exchange of views or ideas that give perspective to all collaborators. In order to make collaborative relationship optimal, all members of the different professions should have a desire to cooperate. Pharmacists and physicians should plan and practice as colleagues, work interdependence within the limits of the scope of practice with a variety of values and knowledge. The role of director in cooperation between doctor and pharmacist takes decision-making which refers to treatment of patients to be decided together between health professionals (physician and pharmacist. The study was a quasi-experimental design with a pre-test-post-test control group design, using paired t-test analysis. The study was conducted from October 2012 until February 2013. The paired t-test results showed that the variable of teamwork effectiveness in M. M. Dunda Hospital increased significantly (p=0.038, which means that the three-party (physician-pharmacist-director collaboration model may increase teamwork effectiveness. Three-party collaboration model can improve physician-pharmacist relationship in the hospital. Leadership has a positive and significant effect on employees’ organizational commitment. Director can be an inspiration in the work and determine the direction and goals of the organization. Therefore, the three-party (physician-pharmacist-director collaboration model can improve the quality of the relationship between the two professions, physician and pharmacist.

  20. A review of logistic regression models used to predict post-fire tree mortality of western North American conifers

    Science.gov (United States)

    Travis Woolley; David C. Shaw; Lisa M. Ganio; Stephen. Fitzgerald

    2012-01-01

    Logistic regression models used to predict tree mortality are critical to post-fire management, planning prescribed bums and understanding disturbance ecology. We review literature concerning post-fire mortality prediction using logistic regression models for coniferous tree species in the western USA. We include synthesis and review of: methods to develop, evaluate...

  1. Forging a link between mentoring and collaboration: a new training model for implementation science.

    Science.gov (United States)

    Luke, Douglas A; Baumann, Ana A; Carothers, Bobbi J; Landsverk, John; Proctor, Enola K

    2016-10-13

    Training investigators for the rapidly developing field of implementation science requires both mentoring and scientific collaboration. Using social network descriptive analyses, visualization, and modeling, this paper presents results of an evaluation of the mentoring and collaborations fostered over time through the National Institute of Mental Health (NIMH) supported by Implementation Research Institute (IRI). Data were comprised of IRI participant self-reported collaborations and mentoring relationships, measured in three annual surveys from 2012 to 2014. Network descriptive statistics, visualizations, and network statistical modeling were conducted to examine patterns of mentoring and collaboration among IRI participants and to model the relationship between mentoring and subsequent collaboration. Findings suggest that IRI is successful in forming mentoring relationships among its participants, and that these mentoring relationships are related to future scientific collaborations. Exponential random graph network models demonstrated that mentoring received in 2012 was positively and significantly related to the likelihood of having a scientific collaboration 2 years later in 2014 (p = 0.001). More specifically, mentoring was significantly related to future collaborations focusing on new research (p = 0.009), grant submissions (p = 0.003), and publications (p = 0.017). Predictions based on the network model suggest that for every additional mentoring relationships established in 2012, the likelihood of a scientific collaboration 2 years later is increased by almost 7 %. These results support the importance of mentoring in implementation science specifically and team science more generally. Mentoring relationships were established quickly and early by the IRI core faculty. IRI fellows reported increasing scientific collaboration of all types over time, including starting new research, submitting new grants, presenting research results, and

  2. Merging assistance function with task distribution model to enhance user performance in collaborative virtual environment

    International Nuclear Information System (INIS)

    Khalid, S.; Alam, A.

    2016-01-01

    Collaborative Virtual Environments (CVEs) falls under Virtual Reality (VR) where two or more users manipulate objects collaboratively. In this paper we have made some experiments to make assembly from constituents parts scattered in Virtual Environment (VE) based on task distribution model using assistance functions for checking and enhancing user performance. The CVEs subjects setting on distinct connected machines via local area network. In this perspective, we consider the effects of assistance function with oral communication on collaboration, co-presence and users performance. Twenty subjects performed collaboratively an assembly task on static and dynamic based task distribution. We examine the degree of influence of assistance function with oral communications on user's performance based on task distribution model. The results show that assistance functions with oral communication based on task distribution model not only increase user performance but also enhance the sense of copresence and awareness. (author)

  3. Confronting human papilloma virus/oropharyngeal cancer: a model for interprofessional collaboration.

    Science.gov (United States)

    Fried, Jacquelyn L

    2014-06-01

    A collaborative practice model related to Human Papilloma Virus (HPV) associated oropharyngeal cancer highlights the role of the dental hygienist in addressing this condition. The incidence of HPV associated head and neck cancer is rising. Multiple professionals including the dental hygienist can work collaboratively to confront this growing public health concern. A critical review applies the growth and utilization of interprofessional education (IPE) and interprofessional collaboration (IPC) to multi-disciplinary models addressing the human papilloma virus and oropharyngeal cancers. A model related to HPV associated oropharyngeal cancer addresses an oral systemic condition that supports the inclusion of a dental hygienist on collaborative teams addressing prevention, detection, treatment and cure of OPC. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. A model of using social media for collaborative learning to enhance learners’ performance on learning

    Directory of Open Access Journals (Sweden)

    Waleed Mugahed Al-Rahmi

    2017-10-01

    Full Text Available Social media has been always described as the channel through which knowledge is transmitted between communities and learners. This social media has been utilized by colleges in a way to encourage collaborative learning and social interaction. This study explores the use of social media in the process of collaborative learning through learning Quran and Hadith. Through this investigation, different factors enhancing collaborative learning in learning Quran and Hadith in the context of using social media are going to be examined. 340 respondents participated in this study. The structural equation modeling (SEM was used to analyze the data obtained. Upon analysis and structural model validities, the study resulted in a model used for measuring the influences of the different variables. The study reported direct and indirect significant impacts of these variables on collaborative learning through the use of social media which might lead to a better performance by learners.

  5. Comparative Evaluation of Five Fire Emissions Datasets Using the GEOS-5 Model

    Science.gov (United States)

    Ichoku, C. M.; Pan, X.; Chin, M.; Bian, H.; Darmenov, A.; Ellison, L.; Kucsera, T. L.; da Silva, A. M., Jr.; Petrenko, M. M.; Wang, J.; Ge, C.; Wiedinmyer, C.

    2017-12-01

    Wildfires and other types of biomass burning affect most vegetated parts of the globe, contributing 40% of the annual global atmospheric loading of carbonaceous aerosols, as well as significant amounts of numerous trace gases, such as carbon dioxide, carbon monoxide, and methane. Many of these smoke constituents affect the air quality and/or the climate system directly or through their interactions with solar radiation and cloud properties. However, fire emissions are poorly constrained in global and regional models, resulting in high levels of uncertainty in understanding their real impacts. With the advent of satellite remote sensing of fires and burned areas in the last couple of decades, a number of fire emissions products have become available for use in relevant research and applications. In this study, we evaluated five global biomass burning emissions datasets, namely: (1) GFEDv3.1 (Global Fire Emissions Database version 3.1); (2) GFEDv4s (Global Fire Emissions Database version 4 with small fires); (3) FEERv1 (Fire Energetics and Emissions Research version 1.0); (4) QFEDv2.4 (Quick Fire Emissions Dataset version 2.4); and (5) Fire INventory from NCAR (FINN) version 1.5. Overall, the spatial patterns of biomass burning emissions from these inventories are similar, although the magnitudes of the emissions can be noticeably different. The inventories derived using top-down approaches (QFEDv2.4 and FEERv1) are larger than those based on bottom-up approaches. For example, global organic carbon (OC) emissions in 2008 are: QFEDv2.4 (51.93 Tg), FEERv1 (28.48 Tg), FINN v1.5 (19.48 Tg), GFEDv3.1 (15.65 Tg) and GFEDv4s (13.76 Tg); representing a factor of 3.7 difference between the largest and the least. We also used all five biomass-burning emissions datasets to conduct aerosol simulations using the NASA Goddard Earth Observing System Model, Version 5 (GEOS-5), and compared the resulting aerosol optical depth (AOD) output to the corresponding retrievals from MODIS

  6. Assessing the outstanding 2003 fire events in Portugal with a Regional Climate Model

    Science.gov (United States)

    Trigo, Ricardo; Jerez, Sonia; Camara, Carlos; Montávez, Juan Pedro

    2013-04-01

    The heatwave that struck western Iberia in the early days of August 2003 was characterized by record high values of both maximum (47.3°C) and minimum (30.6°c) temperatures in Portugal, associated with extremely low humidity levels and relatively intense wind speed (Trigo et al., 2006). These conditions triggered the most devastating sequence of large fires ever registered in Portugal. The estimated total burnt area was about 450.000 ha, including 280.000 ha of forest (Pereira et al., 2011). The outstanding total burnt area value corresponds to roughly 5% of the Portuguese territory, and represents approximately twice the previous maximum observed in 1998 (~220.000 ha), and about four times the long-term average observed between 1980 and 2004. Here we characterise this unusual episode using meteorological fields obtained from both observations and a regional climate model. In this work we use the longest (49-years) high-resolution regional climate simulation available driven by reanalysis data spanning from 1959 to 2007 and covering the entire Iberian Peninsula. This long run was obtained using the MM5 model with a spatial resolution of 10 km. Using this high spatial and temporal resolution we have computed the Canadian Fire Weather Index (FWI) System to produce hourly values of fire risk. The FWI System consists of six components that account for the effects of fuel moisture and wind on fire behaviour (van Wagner, 1987). We show the temporal evolution of high resolution patterns for several fire related variables during the most important days for triggering new fires (the first week of August 2003). Besides the absolute value of Tmax, Tmin, wind (speed and direction), relative humidity and FWI we also evaluate the corresponding anomalies of these fields, obtained after removing the long-term smoothed daily climatology. Pereira M.G., Malamude B.D., Trigo R.M., Alves P.I. (2011) "The History and Characteristics of the 1980-2005 Portuguese Rural Fire Database

  7. Improving fire season definition by optimized temporal modelling of daily human-caused ignitions.

    Science.gov (United States)

    Costafreda-Aumedes, S; Vega-Garcia, C; Comas, C

    2018-07-01

    Wildfire suppression management is usually based on fast control of all ignitions, especially in highly populated countries with pervasive values-at-risk. To minimize values-at-risk loss by improving response time of suppression resources it is necessary to anticipate ignitions, which are mainly caused by people. Previous studies have found that human-ignition patterns change spatially and temporally depending on socio-economic activities, hence, the deployment of suppression resources along the year should consider these patterns. However, full suppression capacity is operational only within legally established fire seasons, driven by past events and budgets, which limits response capacity and increases damages out of them. The aim of this study was to assess the temporal definition of fire seasons from the perspective of human-ignition patterns for the case study of Spain, where people cause over 95% of fires. Humans engage in activities that use fire as a tool in certain periods within a year, and in locations linked to specific spatial factors. Geographic variables (population, infrastructures, physiography and land uses) were used as explanatory variables for human-ignition patterns. The changing influence of these geographic variables on occurrence along the year was analysed with day-by-day logistic regression models. Daily models were built for all the municipal units in the two climatic regions in Spain (Atlantic and Mediterranean Spain) from 2002 to 2014, and similar models were grouped within continuous periods, designated as ignition-based seasons. We found three ignition-based seasons in the Mediterranean region and five in the Atlantic zones, not coincidental with calendar seasons, but with a high degree of agreement with current legally designated operational fire seasons. Our results suggest that an additional late-winter-early-spring fire season in the Mediterranean area and the extension of this same season in the Atlantic zone should be re

  8. Successional changes in trophic interactions support a mechanistic model of post-fire population dynamics.

    Science.gov (United States)

    Smith, Annabel L

    2018-01-01

    Models based on functional traits have limited power in predicting how animal populations respond to disturbance because they do not capture the range of demographic and biological factors that drive population dynamics, including variation in trophic interactions. I tested the hypothesis that successional changes in vegetation structure, which affected invertebrate abundance, would influence growth rates and body condition in the early-successional, insectivorous gecko Nephrurus stellatus. I captured geckos at 17 woodland sites spanning a succession gradient from 2 to 48 years post-fire. Body condition and growth rates were analysed as a function of the best-fitting fire-related predictor (invertebrate abundance or time since fire) with different combinations of the co-variates age, sex and location. Body condition in the whole population was positively affected by increasing invertebrate abundance and, in the adult population, this effect was most pronounced for females. There was strong support for a decline in growth rates in weight with time since fire. The results suggest that increased early-successional invertebrate abundance has filtered through to a higher trophic level with physiological benefits for insectivorous geckos. I integrated the new findings about trophic interactions into a general conceptual model of mechanisms underlying post-fire population dynamics based on a long-term research programme. The model highlights how greater food availability during early succession could drive rapid population growth by contributing to previously reported enhanced reproduction and dispersal. This study provides a framework to understand links between ecological and physiological traits underlying post-fire population dynamics.

  9. Modeling the effects of environmental disturbance on wildlife communities: Avian responses to prescribed fire

    Science.gov (United States)

    Russell, R.E.; Royle, J. Andrew; Saab, V.A.; Lehmkuhl, J.F.; Block, W.M.; Sauer, J.R.

    2009-01-01

    Prescribed fire is a management tool used to reduce fuel loads on public lands in forested areas in the western United States. Identifying the impacts of prescribed fire on bird communities in ponderosa pine (Pinus ponderosa) forests is necessary for providing land management agencies with information regarding the effects of fuel reduction on sensitive, threatened, and migratory bird species. Recent developments in occupancy modeling have established a framework for quantifying the impacts of management practices on wildlife community dynamics. We describe a Bayesian hierarchical model of multi-species occupancy accounting for detection probability, and we demonstrate the model's usefulness for identifying effects of habitat disturbances on wildlife communities. Advantages to using the model include the ability to estimate the effects of environmental impacts on rare or elusive species, the intuitive nature of the modeling, the incorporation of detection probability, the estimation of parameter uncertainty, the flexibility of the model to suit a variety of experimental designs, and the composite estimate of the response that applies to the collection of observed species as opposed to merely a small subset of common species. Our modeling of the impacts of prescribed fire on avian communities in a ponderosa pine forest in Washington indicate that prescribed fire treatments result in increased occupancy rates for several bark-insectivore, cavity-nesting species including a management species of interest, Black-backed Woodpeckers (Picoides arcticus). Three aerial insectivore species, and the ground insectivore, American Robin (Turdus migratorius), also responded positively to prescribed fire, whereas three foliage insectivores and two seed specialists, Clark's Nutcracker (Nucifraga columbiana) and the Pine Siskin (Carduelis pinus), declined following treatments. Land management agencies interested in determining the effects of habitat manipulations on wildlife

  10. Development of collaborative-creative learning model using virtual laboratory media for instrumental analytical chemistry lectures

    Science.gov (United States)

    Zurweni, Wibawa, Basuki; Erwin, Tuti Nurian

    2017-08-01

    The framework for teaching and learning in the 21st century was prepared with 4Cs criteria. Learning providing opportunity for the development of students' optimal creative skills is by implementing collaborative learning. Learners are challenged to be able to compete, work independently to bring either individual or group excellence and master the learning material. Virtual laboratory is used for the media of Instrumental Analytical Chemistry (Vis, UV-Vis-AAS etc) lectures through simulations computer application and used as a substitution for the laboratory if the equipment and instruments are not available. This research aims to design and develop collaborative-creative learning model using virtual laboratory media for Instrumental Analytical Chemistry lectures, to know the effectiveness of this design model adapting the Dick & Carey's model and Hannafin & Peck's model. The development steps of this model are: needs analyze, design collaborative-creative learning, virtual laboratory media using macromedia flash, formative evaluation and test of learning model effectiveness. While, the development stages of collaborative-creative learning model are: apperception, exploration, collaboration, creation, evaluation, feedback. Development of collaborative-creative learning model using virtual laboratory media can be used to improve the quality learning in the classroom, overcome the limitation of lab instruments for the real instrumental analysis. Formative test results show that the Collaborative-Creative Learning Model developed meets the requirements. The effectiveness test of students' pretest and posttest proves significant at 95% confidence level, t-test higher than t-table. It can be concluded that this learning model is effective to use for Instrumental Analytical Chemistry lectures.

  11. Modelling Odor Decoding in the Antennal Lobe by Combining Sequential Firing Rate Models with Bayesian Inference.

    Directory of Open Access Journals (Sweden)

    Dario Cuevas Rivera

    2015-10-01

    Full Text Available The olfactory information that is received by the insect brain is encoded in the form of spatiotemporal patterns in the projection neurons of the antennal lobe. These dense and overlapping patterns are transformed into a sparse code in Kenyon cells in the mushroom body. Although it is clear that this sparse code is the basis for rapid categorization of odors, it is yet unclear how the sparse code in Kenyon cells is computed and what information it represents. Here we show that this computation can be modeled by sequential firing rate patterns using Lotka-Volterra equations and Bayesian online inference. This new model can be understood as an 'intelligent coincidence detector', which robustly and dynamically encodes the presence of specific odor features. We found that the model is able to qualitatively reproduce experimentally observed activity in both the projection neurons and the Kenyon cells. In particular, the model explains mechanistically how sparse activity in the Kenyon cells arises from the dense code in the projection neurons. The odor classification performance of the model proved to be robust against noise and time jitter in the observed input sequences. As in recent experimental results, we found that recognition of an odor happened very early during stimulus presentation in the model. Critically, by using the model, we found surprising but simple computational explanations for several experimental phenomena.

  12. XSIM Final Report: Modelling the Past and Future of Identity Management for Scientific Collaborations

    Energy Technology Data Exchange (ETDEWEB)

    Cowles, Robert; Jackson, Craig; Welch, Von

    2016-08-31

    The eXtreme Science Identity Management (XSIM1) research project: collected and analyzed real world data on virtual organization (VO) identity management (IdM) representing the last 15+ years of collaborative DOE science; constructed a descriptive VO IdM model based on that data; used the model and existing trends to project the direction for IdM in the 2020 timeframe; and provided guidance to scientific collaborations and resource providers that are implementing or seeking to improve IdM functionality. XSIM conducted over 20 semi­structured interviews of representatives from scientific collaborations and resource providers, both in the US and Europe; the interviewees supported diverse set of scientific collaborations and disciplines. We developed a definition of “trust,” a key concept in IdM, to understand how varying trust models affect where IdM functions are performed. The model identifies how key IdM data elements are utilized in collaborative scientific workflows, and it has the flexibility to describe past, present and future trust relationships and IdM implementations. During the funding period, we gave more than two dozen presentations to socialize our work, encourage feedback, and improve the model; we also published four refereed papers. Additionally, we developed, presented, and received favorable feedback on three white papers providing practical advice to collaborations and/or resource providers.

  13. Dayton Aircraft Cabin Fire Model, Version 3, Volume I. Physical Description.

    Science.gov (United States)

    1982-06-01

    contact to any surface directly above a burning element, provided that the current flame length makes contact possible. For fires originating on the...no extension of the flames horizontally beneath the surface is considered. The equation for computing the flame length is presented in Section 5. For...high as 0.3. The values chosen for DACFIR3 are 0.15 for Ec and 0.10 for E P. The Steward model is also used to compute flame length , hf, for the fire

  14. Modeling the differentiation of A- and C-type baroreceptor firing patterns

    DEFF Research Database (Denmark)

    Sturdy, Jacob; Ottesen, Johnny T.; Olufsen, Mette

    2017-01-01

    The baroreceptor neurons serve as the primary transducers of blood pressure for the autonomic nervous system and are thus critical in enabling the body to respond effectively to changes in blood pressure. These neurons can be separated into two types (A and C) based on the myelination...... of their axons and their distinct firing patterns elicited in response to specific pressure stimuli. This study has developed a comprehensive model of the afferent baroreceptor discharge built on physiological knowledge of arterial wall mechanics, firing rate responses to controlled pressure stimuli, and ion...

  15. Physical characterization of biomass fuels prepared for suspension firing in utility boilers for CFD modelling

    DEFF Research Database (Denmark)

    Rosendahl, Lasse; Yin, Chungen; Kær, Søren Knudsen

    2007-01-01

    A sample of 1.2 kg Danish wheat straw (Jutland, 1997) prepared for suspension firing in a PF boiler has been analyzed for the purpose of generating size and shape distribution functions applicable to numerical modelling of combustion processes involving biomass, characterised by highly anisotropic...... shapes. The sample is subdivided by straw type, and coherent size, type and mass distribution parameters are reported for the entire sample. This type of data is necessary in order to use CFD reliably as a design and retrofit tool for co-firing biomass with fossil fuels, as the combustion processes...

  16. Scrum integration in stage-gate models for collaborative product development

    DEFF Research Database (Denmark)

    Sommer, Anita Friis; Slavensky, Andreas; Nguyen, Vivi Thuy

    2013-01-01

    to differentiate from low-cost competitors and increase PD performance, some industrial manufacturers now seek competitive advantage by experimenting with new ways for collaborative PD. This includes integrating customer-focused agile process models, like Scrum, from the software industry into their existing PD...... models. Thus, instead of replacing traditional stage-gate models agile methods are currently integrated in existing PD models generating hybrid solution for collaborative PD. This paper includes a study of three industrial cases that have successfully integrated Scrum into a stage-gate process model...

  17. Reducing the computational requirements for simulating tunnel fires by combining multiscale modelling and multiple processor calculation

    DEFF Research Database (Denmark)

    Vermesi, Izabella; Rein, Guillermo; Colella, Francesco

    2017-01-01

    Multiscale modelling of tunnel fires that uses a coupled 3D (fire area) and 1D (the rest of the tunnel) model is seen as the solution to the numerical problem of the large domains associated with long tunnels. The present study demonstrates the feasibility of the implementation of this method...... in FDS version 6.0, a widely used fire-specific, open source CFD software. Furthermore, it compares the reduction in simulation time given by multiscale modelling with the one given by the use of multiple processor calculation. This was done using a 1200m long tunnel with a rectangular cross......-section as a demonstration case. The multiscale implementation consisted of placing a 30MW fire in the centre of a 400m long 3D domain, along with two 400m long 1D ducts on each side of it, that were again bounded by two nodes each. A fixed volume flow was defined in the upstream duct and the two models were coupled...

  18. Cortical Network Models of Firing Rates in the Resting and Active States Predict BOLD Responses.

    Directory of Open Access Journals (Sweden)

    Maxwell R Bennett

    Full Text Available Measurements of blood oxygenation level dependent (BOLD signals have produced some surprising observations. One is that their amplitude is proportional to the entire activity in a region of interest and not just the fluctuations in this activity. Another is that during sleep and anesthesia the average BOLD correlations between regions of interest decline as the activity declines. Mechanistic explanations of these phenomena are described here using a cortical network model consisting of modules with excitatory and inhibitory neurons, taken as regions of cortical interest, each receiving excitatory inputs from outside the network, taken as subcortical driving inputs in addition to extrinsic (intermodular connections, such as provided by associational fibers. The model shows that the standard deviation of the firing rate is proportional to the mean frequency of the firing when the extrinsic connections are decreased, so that the mean BOLD signal is proportional to both as is observed experimentally. The model also shows that if these extrinsic connections are decreased or the frequency of firing reaching the network from the subcortical driving inputs is decreased, or both decline, there is a decrease in the mean firing rate in the modules accompanied by decreases in the mean BOLD correlations between the modules, consistent with the observed changes during NREM sleep and under anesthesia. Finally, the model explains why a transient increase in the BOLD signal in a cortical area, due to a transient subcortical input, gives rises to responses throughout the cortex as observed, with these responses mediated by the extrinsic (intermodular connections.

  19. Fire simulation in large compartments with a fire model 'CFAST'. Part 1. Survey of applicability for analyzing air-temperature profile in compartments

    International Nuclear Information System (INIS)

    Hattori, Yasuo; Suto, Hitoshi; Shirai, Koji; Eguchi, Yuzuru; Sano, Tadashi

    2012-01-01

    The basic performance of numerical analysis of air-temperature profiles in large-scale compartments by using a zone model, CFAST (Consolidated model of Fire growth And Smoke Transport), which has been widely applied for fire protection design of buildings is examined. Special attentions are paid to the dependence of the setting boundary conditions and the choosing model parameters. The simulations carried out under the denkyoken-test conditions, in which the air-temperature profiles in compartments and the heat-release rate of a fire have been precisely measured, indicate that the CFAST has a capability to appropriately represent the time-histories of air-temperature in the high air-temperature layer generated in the vicinity of ceiling of the compartment which includes the source of a fire, by applying the proper boundary conditions, i.e., time-histories of air-temperature in the upper (high temperature) layer given by the CFAST agree well with those of observations. The sensitivity analysis in the simulations also reveals that the appropriately setting of the boundary-conditions, especially for the heat-release ratio from a fire and the heat-transfer rate from walls of compartments to ambient air is vital. Contrary to this, the impacts of choosing numerical parameters on the air-temperature analysis are quite small. (author)

  20. Model fire tests on polyphosphazene rubber and polyvinyl chloride (PVC)/nitrile rubber foams

    Science.gov (United States)

    Widenor, W. M.

    1978-01-01

    A video tape record of model room fire tests was shown, comparing polyphosphazene (P-N) rubber and polyvinyl chloride (PVC)/nitrile rubber closed-cell foams as interior finish thermal insulation under conditions directly translatable to an actual fire situation. Flashover did not occur with the P-N foam and only moderate amounts of low density smoke were formed, whereas with the PVC/nitrile foam, flashover occurred quickly and large volumes of high density smoke were emitted. The P-N foam was produced in a pilot plant under carefully controlled conditions. The PVC/nitrile foam was a commercial product. A major phase of the overall program involved fire tests on P-N open-cell foam cushioning.

  1. Control of clustered action potential firing in a mathematical model of entorhinal cortex stellate cells.

    Science.gov (United States)

    Tait, Luke; Wedgwood, Kyle; Tsaneva-Atanasova, Krasimira; Brown, Jon T; Goodfellow, Marc

    2018-07-14

    The entorhinal cortex is a crucial component of our memory and spatial navigation systems and is one of the first areas to be affected in dementias featuring tau pathology, such as Alzheimer's disease and frontotemporal dementia. Electrophysiological recordings from principle cells of medial entorhinal cortex (layer II stellate cells, mEC-SCs) demonstrate a number of key identifying properties including subthreshold oscillations in the theta (4-12 Hz) range and clustered action potential firing. These single cell properties are correlated with network activity such as grid firing and coupling between theta and gamma rhythms, suggesting they are important for spatial memory. As such, experimental models of dementia have revealed disruption of organised dorsoventral gradients in clustered action potential firing. To better understand the mechanisms underpinning these different dynamics, we study a conductance based model of mEC-SCs. We demonstrate that the model, driven by extrinsic noise, can capture quantitative differences in clustered action potential firing patterns recorded from experimental models of tau pathology and healthy animals. The differential equation formulation of our model allows us to perform numerical bifurcation analyses in order to uncover the dynamic mechanisms underlying these patterns. We show that clustered dynamics can be understood as subcritical Hopf/homoclinic bursting in a fast-slow system where the slow sub-system is governed by activation of the persistent sodium current and inactivation of the slow A-type potassium current. In the full system, we demonstrate that clustered firing arises via flip bifurcations as conductance parameters are varied. Our model analyses confirm the experimentally suggested hypothesis that the breakdown of clustered dynamics in disease occurs via increases in AHP conductance. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Statistical aspects of carbon fiber risk assessment modeling. [fire accidents involving aircraft

    Science.gov (United States)

    Gross, D.; Miller, D. R.; Soland, R. M.

    1980-01-01

    The probabilistic and statistical aspects of the carbon fiber risk assessment modeling of fire accidents involving commercial aircraft are examined. Three major sources of uncertainty in the modeling effort are identified. These are: (1) imprecise knowledge in establishing the model; (2) parameter estimation; and (3)Monte Carlo sampling error. All three sources of uncertainty are treated and statistical procedures are utilized and/or developed to control them wherever possible.

  3. The Effects of Modern-Day Cropland and Pasture Management on Vegetation Fire: An Earth System Modeling Approach

    Science.gov (United States)

    Rabin, S. S.; Malyshev, S.; Shevliakova, E.; Pacala, S. W.

    2014-12-01

    Fire is a major component of the global carbon cycle, with some estimates of the associated emissions reaching 2.5 PgC/yr. This and the other impacts of biomass burning have driven efforts to improve its simulation in Earth system models. Recent global fire models usually include both bioclimatic and anthropogenic drivers of fire, with the latter (via population density and sometimes economic status) serving to increase or suppress burned area. Some models have added the representation of fire used in deforestation and cropland management, the extent and seasonal timing of which may not be accounted for by the usual approach to anthropogenic influence. Human land use can also limit fire by fragmenting landscapes, but this process is not included in most global models. Moreover, although people often use fire to manage grazing lands for livestock, these practices have not been explicitly modeled (except as performed by pre-industrial societies). This could be important for regions such as sub-Saharan Africa, where the seasonality of pasture burning tends to differ from that of other lands, potentially influencing savanna-forest dynamics. Recent efforts elucidating the effects of cropland and pasture on fire regimes at regional scales provide insight into these processes. Using this new understanding, we have developed a fire model with structurally distinct modules for burning of croplands, pasture, and primary and secondary lands, as well as fire use for deforestation. Parameters for each are rigorously constrained using remote-sensing observations of burned area. This structure allows us to disentangle agricultural practices and fragmentation effects from the endogenous processes driving fire on non-agricultural land, resulting in a better ability to simulate how fire works at large scales. This is critical for modeling the future of fire and all the parts of the Earth system that it affects, including vegetation distributions, nutrient cycling, and biosphere

  4. Collaborative Economy

    DEFF Research Database (Denmark)

    that are emerging from them, and how governments are responding to these new challenges. In doing so, the book provides both theoretical and practical insights into the future of tourism in a world that is, paradoxically, becoming both increasingly collaborative and individualized. Table of Contents Preface 1.The...... collaborative economy and tourism Dianne Dredge and Szilvia Gyimóthy PART I - Theoretical explorations 2.Definitions and mapping the landscape in the collaborative economy Szilvia Gyimóthy and Dianne Dredge 3.Business models of the collaborative economy Szilvia Gyimóthy 4.Responsibility and care...... in the collaborative economy Dianne Dredge 5.Networked cultures in the collaborative economy Szilvia Gyimóthy 6.Policy and regulatory perspectives in the collaborative economy Dianne Dredge PART II - Disruptions, innovations and transformations 7.Regulating innovation in the collaborative economy: An examination...

  5. Structured spatio-temporal shot-noise Cox point process models, with a view to modelling forest fires

    DEFF Research Database (Denmark)

    Møller, Jesper; Diaz-Avalos, Carlos

    Spatio-temporal Cox point process models with a multiplicative structure for the driving random intensity, incorporating covariate information into temporal and spatial components, and with a residual term modelled by a shot-noise process, are considered. Such models are flexible and tractable fo...... dataset consisting of 2796 days and 5834 spatial locations of fires. The model is compared with a spatio-temporal log-Gaussian Cox point process model, and likelihood-based methods are discussed to some extent....

  6. Three Tier Unified Process Model for Requirement Negotiations and Stakeholder Collaborations

    Science.gov (United States)

    Niazi, Muhammad Ashraf Khan; Abbas, Muhammad; Shahzad, Muhammad

    2012-11-01

    This research paper is focused towards carrying out a pragmatic qualitative analysis of various models and approaches of requirements negotiations (a sub process of requirements management plan which is an output of scope managementís collect requirements process) and studies stakeholder collaborations methodologies (i.e. from within communication management knowledge area). Experiential analysis encompass two tiers; first tier refers to the weighted scoring model while second tier focuses on development of SWOT matrices on the basis of findings of weighted scoring model for selecting an appropriate requirements negotiation model. Finally the results are simulated with the help of statistical pie charts. On the basis of simulated results of prevalent models and approaches of negotiations, a unified approach for requirements negotiations and stakeholder collaborations is proposed where the collaboration methodologies are embeded into selected requirements negotiation model as internal parameters of the proposed process alongside some external required parameters like MBTI, opportunity analysis etc.

  7. Future Integrated Fire Control

    National Research Council Canada - National Science Library

    Young, Bonnie W

    2005-01-01

    Future advances in fire control for air and missile defense depend largely on a network-enabled foundation that enables the collaborative use of distributed warfare assets for time-critical operations...

  8. Cooperation Models, Motivation and Objectives behind Farm–School Collaboration

    DEFF Research Database (Denmark)

    Dyg, Pernille Malberg; Mikkelsen, Bent Egberg

    2016-01-01

    economic incentives. Teachers display academic motives for engaging in farm visits, but also a broader focus on shaping children’s world views, connectedness to food and nature and fostering life skills. The farm can be an important setting for promoting food, agricultural and ecological literacy. We...... people and their ability to understand the food system. Thus, efforts are made to promote food literacy through strengthening of farm–school links. The case-study research from Denmark investigates existing cooperation arrangements in farm–school collaboration and the underlying motivation of the farmers...... and teachers. Findings show distinct differences in motivation. Farmers want to create transparency in their production, ensure support for the agricultural profession or promote food and agricultural literacy. The idealistic motivation of teaching children about food and agriculture weighs higher than...

  9. A study on fire spreading model for the safety distance between the neighborhood occupancies and historical buildings in Taiwan

    Science.gov (United States)

    Chen, C. H.; Chien, S. W.; Ho, M. C.

    2015-08-01

    Cultural heritages and historical buildings are vulnerable against severe threats from fire. Since the 1970s, ten fire-spread events involving historic buildings have occurred in Taiwan, affecting a total of 132 nearby buildings. Developed under the influence of traditional Taiwanese culture, historic buildings in Taiwan are often built using non-fire resistant brick-wood structure and located in proximity to residential occupancies. Fire outbreak in these types of neighborhood will lead to severe damage of antiquities, leaving only unrecoverable historical imagery. This study is aimed to investigate the minimal safety distance required between a historical building and its surroundings in order to reduce the risk of external fire. This study is based on literature analysis and the fire spread model using a Fire Dynamics Simulator. The selected target is Jingmei Temple in Taipei City. This study explored local geography to identify patterns behind historical buildings distribution. In the past, risk reduction engineering for cultural heritages and historical buildings focused mainly on fire equipment and the available personnel with emergency response ability, and little attention was given to external fire risks and the affected damage. Through discussions on the required safety distance, this research provides guidelines for the following items: management of neighborhoods with historical buildings and consultation between the protection of cultural heritages and disaster prevention, reducing the frequency and extent of fire damages, and preserving cultural resource.

  10. Combining engineering and data-driven approaches: Development of a generic fire risk model facilitating calibration

    DEFF Research Database (Denmark)

    De Sanctis, G.; Fischer, K.; Kohler, J.

    2014-01-01

    Fire risk models support decision making for engineering problems under the consistent consideration of the associated uncertainties. Empirical approaches can be used for cost-benefit studies when enough data about the decision problem are available. But often the empirical approaches...... a generic risk model that is calibrated to observed fire loss data. Generic risk models assess the risk of buildings based on specific risk indicators and support risk assessment at a portfolio level. After an introduction to the principles of generic risk assessment, the focus of the present paper...... are not detailed enough. Engineering risk models, on the other hand, may be detailed but typically involve assumptions that may result in a biased risk assessment and make a cost-benefit study problematic. In two related papers it is shown how engineering and data-driven modeling can be combined by developing...

  11. Implications of introducing realistic fire response traits in a Dynamic Global Vegetation Model

    Science.gov (United States)

    Kelley, D.; Harrison, S. P.; Prentice, I. C.

    2013-12-01

    Bark thickness is a key trait protecting woody plants against fire damage, while the ability to resprout is a trait that confers competitive advantage over non-resprouting individuals in fire-prone landscapes. Neither trait is well represented in fire-enabled dynamic global vegetation models (DGVMs). Here we describe a version of the Land Processes and eXchanges (LPX-Mv1) DGVM that incorporates both of these traits in a realistic way. From a synthesis of a large number of field studies, we show there is considerable innate variability in bark thickness between species within a plant-functional type (PFT). Furthermore, bark thickness is an adaptive trait at ecosystem level, increasing with fire frequency. We use the data to specify the range of bark thicknesses characteristic of each model PFT. We allow this distribution to change dynamically: thinner-barked trees are killed preferentially by fire, shifting the distribution of bark thicknesses represented in a model grid cell. We use the PFT-specific bark-thickness probability range for saplings during re-establishment. Since it is rare to destroy all trees in a grid cell, this treatment results in average bark thickness increasing with fire frequency and intensity. Resprouting is a prominent adaptation of temperate and tropical trees in fire-prone areas. The ability to resprout from above-ground tissue (apical or epicormic resprouting) results in the fastest recovery of total biomass after disturbance; resprouting from basal or below-ground meristems results in slower recovery, while non-resprouting species must regenerate from seed and therefore take the longest time to recover. Our analyses show that resprouting species have thicker bark than non-resprouting species. Investment in resprouting is accompanied by reduced efficacy of regeneration from seed. We introduce resprouting PFTs in LPX-Mv1 by specifying an appropriate range of bark thickness, allowing resprouters to survive fire and regenerate vegetatively in

  12. Daily and Hourly Variability in Global Fire Emissions and Consequences for Atmospheric Model Predictions of Carbon Monoxide

    Science.gov (United States)

    Mu, M.; Randerson, J. T.; van der Werf, G. R.; Giglio, L.; Kasibhatla, P.; Morton, D.; Collatz, G. J.; DeFries, R. S.; Hyer, E. J.; Prins, E. M.; hide

    2011-01-01

    Attribution of the causes of atmospheric trace gas and aerosol variability often requires the use of high resolution time series of anthropogenic and natural emissions inventories. Here we developed an approach for representing synoptic- and diurnal-scale temporal variability in fire emissions for the Global Fire Emissions Database version 3 (GFED3). We distributed monthly GFED3 emissions during 2003-2009 on a daily time step using Moderate Resolution Imaging Spectroradiometer (MODIS)-derived measurements of active fires from Terra and Aqua satellites. In parallel, mean diurnal cycles were constructed from Geostationary Operational Environmental Satellite (GOES) active fire observations. We found that patterns of daily variability in fires varied considerably across different biomes, with short but intense periods of daily emissions in boreal ecosystems and lower intensity (but more continuous) periods of bunting in savannas. On diurnal timescales, our analysis of the GOES active fires indicated that fires in savannas, grasslands, and croplands occurred earlier in the day as compared to fires in nearby forests. Comparison with Total Carbon Column Observing Network (TCCON) and Measurements of Pollution in the Troposphere (MOPITT) column CO observations provided evidence that including daily variability in emissions moderately improved atmospheric model simulations, particularly during the fire season and near regions with high levels of biomass burning. The high temporal resolution estimates of fire emissions developed here may ultimately reduce uncertainties related to fire contributions to atmospheric trace gases and aerosols. Important future directions include reconciling top-down and bottom up estimates of fire radiative power and integrating burned area and active fire time series from multiple satellite sensors to improve daily emissions estimates.

  13. A Proposed Model for Measuring Performance of the University-Industry Collaboration in Open Innovation

    OpenAIRE

    Anca Draghici; Larisa Ivascu; Adrian Mateescu; George Draghici

    2017-01-01

    The paper aims to present a scientific approach to the creation, testing and validation of a model for performance measurement for university-industry collaboration (UIC). The main idea of the design process is to capitalize on existing success factors, facilitators and opportunities (motivation factors, knowledge transfer channels and identified benefits) and to diminish or avoid potential threats and barriers that might interfere with such collaborations. The main purpose ...

  14. The Collaborative Management Model on Developing the Infrastructure of the Pomalaa’s Airport, Indonesia

    Directory of Open Access Journals (Sweden)

    Dr.Sc. Abdul Sabaruddin

    2017-06-01

    Full Text Available Collaborative management of public sector is being introduced as a new approach to solve the problems which is mainly on the restrictiveness of bureaucracy in answering such public demand. Therefore, collaboration approach presents new actors out of the government in processing the public sectors. The relationship among actors in its collaboration is well developed through consensus to gain valuable decision to all. Based on the problems mentioned, this study focuses on the model of collaborative management on developing the infrastructure of an airport. To answer the objective of the study, therefore, this research applied qualitative approach in which the respondents are those who were being involved in construction process of the airport. The data gained from interview will be analysed through interactive model consisting of some procedures; data reduction, data presentation, verification of the data/ drawing conclusion. The result showed that collaborative management model in infrastructure development of the airport was a management model, in this case collective action based on the principle of synergetic participation. In this context, there was no single actor on the development of infrastructure of the airport. Through collective action, the related aspects, in this case the development of infrastructure, was transparently communicated to avoid miscommunication among the members. Therefore, the actors which were being involved on the collaboration bore the needs reasonably and also there was no such member who were being burden. Thus, the implication of collaboration based on the consensus, the collaboration on the development of infrastructure of the airport is on the basis of participative, which pointed out the appointment and the continuation of the development.

  15. Model petri net of adaptive traffic lights and its collaboration with a special event

    Directory of Open Access Journals (Sweden)

    Tristono Tomi

    2018-01-01

    Full Text Available Traffic lights have an important role as the system control of vehicles flow on the urban network. Commonly, most countries still using fixed time strategy. Our research proposes the adaptive traffic lights model to response the traffic demand. It uses basic Petri net as a general modeling framework. Foractuating method of minimum and maximum green signal time interval, the green traffic lights have three-time extension units. Next, we collaborate on a case of the existence of railways that crosses on the southern arm of an intersection. We introduce both of collaboration model design of traffic lights and the railway's gate which always closes while a train passing. Verification and validation of the model are based on the simulation result of vehicles queue. The collaboration model design of traffic lights has excellent performance, and it can resolve the congestion problem better than conventional schedule.

  16. Application of wildfire spread and behavior models to assess fire probability and severity in the Mediterranean region

    Science.gov (United States)

    Salis, Michele; Arca, Bachisio; Bacciu, Valentina; Spano, Donatella; Duce, Pierpaolo; Santoni, Paul; Ager, Alan; Finney, Mark

    2010-05-01

    Characterizing the spatial pattern of large fire occurrence and severity is an important feature of the fire management planning in the Mediterranean region. The spatial characterization of fire probabilities, fire behavior distributions and value changes are key components for quantitative risk assessment and for prioritizing fire suppression resources, fuel treatments and law enforcement. Because of the growing wildfire severity and frequency in recent years (e.g.: Portugal, 2003 and 2005; Italy and Greece, 2007 and 2009), there is an increasing demand for models and tools that can aid in wildfire prediction and prevention. Newer wildfire simulation systems offer promise in this regard, and allow for fine scale modeling of wildfire severity and probability. Several new applications has resulted from the development of a minimum travel time (MTT) fire spread algorithm (Finney, 2002), that models the fire growth searching for the minimum time for fire to travel among nodes in a 2D network. The MTT approach makes computationally feasible to simulate thousands of fires and generate burn probability and fire severity maps over large areas. The MTT algorithm is imbedded in a number of research and fire modeling applications. High performance computers are typically used for MTT simulations, although the algorithm is also implemented in the FlamMap program (www.fire.org). In this work, we described the application of the MTT algorithm to estimate spatial patterns of burn probability and to analyze wildfire severity in three fire prone areas of the Mediterranean Basin, specifically Sardinia (Italy), Sicily (Italy) and Corsica (France) islands. We assembled fuels and topographic data for the simulations in 500 x 500 m grids for the study areas. The simulations were run using 100,000 ignitions under weather conditions that replicated severe and moderate weather conditions (97th and 70th percentile, July and August weather, 1995-2007). We used both random ignition locations

  17. Implementation and verification of a coupled fire model as a thermal boundary condition within P3/THERMAL

    International Nuclear Information System (INIS)

    Hensinger, D.M.; Gritzo, L.A.; Koski, J.A.

    1996-01-01

    A user-defined boundary condition subroutine has been implemented within P3/THERMAL to represent the heat flux between a noncombusting object and an engulfing fire. The heat flux calculations includes a simple 2D fire model in which energy and radiative heat transport equations are solved to produce estimates of the heat fluxes at the fire-object interface. These estimates reflect radiative coupling between a cold object and the flow of hot combustion gases which has been observed in fire experiments. The model uses a database of experimental pool fire measurements for far field boundary conditions and volumetric heat release rates. Taking into account the coupling between a structure and the fire is an improvement over the σT 4 approximation frequently used as a boundary condition for engineered system response and is the preliminary step in the development of a fire model with a predictive capability. This paper describes the implementation of the fire model as a P3/THERMAL boundary condition and presents the results of a verification calculation carried out using the model

  18. Enabling model checking for collaborative process analysis: from BPMN to `Network of Timed Automata'

    Science.gov (United States)

    Mallek, Sihem; Daclin, Nicolas; Chapurlat, Vincent; Vallespir, Bruno

    2015-04-01

    Interoperability is a prerequisite for partners involved in performing collaboration. As a consequence, the lack of interoperability is now considered a major obstacle. The research work presented in this paper aims to develop an approach that allows specifying and verifying a set of interoperability requirements to be satisfied by each partner in the collaborative process prior to process implementation. To enable the verification of these interoperability requirements, it is necessary first and foremost to generate a model of the targeted collaborative process; for this research effort, the standardised language BPMN 2.0 is used. Afterwards, a verification technique must be introduced, and model checking is the preferred option herein. This paper focuses on application of the model checker UPPAAL in order to verify interoperability requirements for the given collaborative process model. At first, this step entails translating the collaborative process model from BPMN into a UPPAAL modelling language called 'Network of Timed Automata'. Second, it becomes necessary to formalise interoperability requirements into properties with the dedicated UPPAAL language, i.e. the temporal logic TCTL.

  19. Modeling and Capturing Users’ Actions in CSCL Systems for Collaboration Analysis Purposes

    Directory of Open Access Journals (Sweden)

    Manuel Ortega

    2009-03-01

    Full Text Available A significant number of CSCL (Computer-Supported Collaborative Learning environments support the learning of groups of students enabling their collaboration in solving problems. These collaborative environments usually need additional computational support to allow the automatic processing of both the actions carried out by the students and the end solution with the aim of studying the learning process and the validity of the solution proposed to the problem. This process, known as Collaboration and Interaction Analysis, is typically carried out in three phases: observation, abstraction and intervention. In this paper, we propose a methodological approach for the design of mechanisms for the observation phase. This approach provides a set of procedures enabling developers to design observation systems in CSCL environments that capture and model all the information required for comprehensive analyses of the collaboration process and the resulting solution to the problem. This methodological approach is put into practice by means of its use in the design of an observation system in the SPACE-DESIGN (SPecification and Automatic Construction of collaborative Environments of DESIGN collaborative environment.

  20. A spiking network model of cerebellar Purkinje cells and molecular layer interneurons exhibiting irregular firing

    Directory of Open Access Journals (Sweden)

    William eLennon

    2014-12-01

    Full Text Available While the anatomy of the cerebellar microcircuit is well studied, how it implements cerebellar function is not understood. A number of models have been proposed to describe this mechanism but few emphasize the role of the vast network Purkinje cells (PKJs form with the molecular layer interneurons (MLIs – the stellate and basket cells. We propose a model of the MLI-PKJ network composed of simple spiking neurons incorporating the major anatomical and physiological features. In computer simulations, the model reproduces the irregular firing patterns observed in PKJs and MLIs in vitro and a shift toward faster, more regular firing patterns when inhibitory synaptic currents are blocked. In the model, the time between PKJ spikes is shown to be proportional to the amount of feedforward inhibition from an MLI on average. The two key elements of the model are: (1 spontaneously active PKJs and MLIs due to an endogenous depolarizing current, and (2 adherence to known anatomical connectivity along a parasagittal strip of cerebellar cortex. We propose this model to extend previous spiking network models of the cerebellum and for further computational investigation into the role of irregular firing and MLIs in cerebellar learning and function.

  1. A qualitative comparison of fire spread models incorporating wind and slope effects

    Science.gov (United States)

    David R. Weise; Gregory S. Biging

    1997-01-01

    Wind velocity and slope are two critical variables that affect wildland fire rate of spread. The effects of these variables on rate of spread are often combined in rate-of-spread models using vector addition. The various methods used to combine wind and slope effects have seldom been validated or compared due to differences in the models or to lack of data. In this...

  2. Computing the Local Field Potential (LFP) from Integrate-and-Fire Network Models

    DEFF Research Database (Denmark)

    Mazzoni, Alberto; Linden, Henrik; Cuntz, Hermann

    2015-01-01

    Leaky integrate-and-fire (LIF) network models are commonly used to study how the spiking dynamics of neural networks changes with stimuli, tasks or dynamic network states. However, neurophysiological studies in vivo often rather measure the mass activity of neuronal microcircuits with the local f...... in cases where a single pyramidal population dominates the LFP generation, and thereby facilitate quantitative comparison between computational models and experimental LFP recordings in vivo....

  3. Complex Behavior in an Integrate-and-Fire Neuron Model Based on Small World Networks

    International Nuclear Information System (INIS)

    Lin Min; Chen Tianlun

    2005-01-01

    Based on our previously pulse-coupled integrate-and-fire neuron model in small world networks, we investigate the complex behavior of electroencephalographic (EEG)-like activities produced by such a model. We find EEG-like activities have obvious chaotic characteristics. We also analyze the complex behaviors of EEG-like signals, such as spectral analysis, reconstruction of the phase space, the correlation dimension, and so on.

  4. Use of Video Modeling to Teach Extinguishing of Cooking Related Fires to Individuals with Moderate Intellectual Disabilities

    Science.gov (United States)

    Mechling, Linda C.; Gast, David L.; Gustafson, Melissa R.

    2009-01-01

    This study evaluated the effectiveness of video modeling to teach fire extinguishing behaviors to three young adults with moderate intellectual disabilities. A multiple probe design across three fire extinguishing behaviors and replicated across three students was used to evaluate the effectiveness of the video-based program. Results indicate that…

  5. Incorporating field wind data into FIRETEC simulations of the International Crown Fire Modeling Experiment (ICFME): preliminary lessons learned

    Science.gov (United States)

    Rodman Linn; Kerry Anderson; Judith Winterkamp; Alyssa Broos; Michael Wotton; Jean-Luc Dupuy; Francois Pimont; Carleton Edminster

    2012-01-01

    Field experiments are one way to develop or validate wildland fire-behavior models. It is important to consider the implications of assumptions relating to the locality of measurements with respect to the fire, the temporal frequency of the measured data, and the changes to local winds that might be caused by the experimental configuration. Twenty FIRETEC simulations...

  6. Multiplatform inversion of the 2013 Rim Fire smoke emissions using regional-scale modeling: important nocturnal fire activity, air quality, and climate impacts

    Science.gov (United States)

    Saide, P. E.; Peterson, D. A.; da Silva, A. M., Jr.; Ziemba, L. D.; Anderson, B.; Diskin, G. S.; Sachse, G. W.; Hair, J. W.; Butler, C. F.; Fenn, M. A.; Jimenez, J. L.; Campuzano Jost, P.; Dibb, J. E.; Yokelson, R. J.; Toon, B.; Carmichael, G. R.

    2014-12-01

    Large wildfire events are increasingly recognized for their adverse effects on air quality and visibility, thus providing motivation for improving smoke emission estimates. The Rim Fire, one of the largest events in California's history, produced a large smoke plume that was sampled by the Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC4RS) DC-8 aircraft with a full suite of in-situ and remote sensing measurements on 26-27 August 2013. We developed an inversion methodology which uses the WRF-Chem modeling system to constrain hourly fire emissions, using as initial estimates the NASA Quick Fire Emissions Dataset (QFED). This method differs from the commonly performed top-down estimates that constrain daily (or longer time scale) emissions. The inversion method is able to simultaneously improve the model fit to various SEAC4RS airborne measurements (e.g., organic aerosol, carbon monoxide (CO), aerosol extinction), ground based measurements (e.g., AERONET aerosol optical depth (AOD), CO), and satellite data (MODIS AOD) by modifying fire emissions and utilizing the information content of all these measurements. Preliminary results show that constrained emissions for a 6 day period following the largest fire growth are a factor 2-4 higher than the initial top-down estimates. Moreover, there is a tendency to increase nocturnal emissions by factors sometimes larger than 20, indicating that vigorous fire activity continued during the night. This deviation from a typical diurnal cycle is confirmed using geostationary satellite data. The constrained emissions also have a larger day-to-day variability than the initial emissions and correlate better to daily area burned estimates as observed by airborne infrared measurements (NIROPS). Experiments with the assimilation system show that performing the inversion using only satellite AOD data produces much smaller correction factors than when using all available data

  7. The Comparative Study of Collaborative Learning and SDLC Model to develop IT Group Projects

    Directory of Open Access Journals (Sweden)

    Sorapak Pukdesree

    2017-11-01

    Full Text Available The main objectives of this research were to compare the attitudes of learners between applying SDLC model with collaborative learning and typical SDLC model and to develop electronic courseware as group projects. The research was a quasi-experimental research. The populations of the research were students who took Computer Organization and Architecture course in the academic year 2015. There were 38 students who participated to the research. The participants were divided voluntary into two groups including an experimental group with 28 students using SDLC model with collaborative learning and a control group with 10 students using typical SDLC model. The research instruments were attitude questionnaire, semi-structured interview and self-assessment questionnaire. The collected data was analysed by arithmetic mean, standard deviation, and independent sample t-test. The results of the questionnaire revealed that the attitudes of the learners using collaborative learning and SDLC model were statistically significant difference between the mean score for experimental group and control group at a significance level of 0.05. The independent statistical analyses were significantly different between the two groups at a significance level of 0.05. The results of the interviewing revealed that most of the learners had the corresponding opinions that collaborative learning was very useful with highest level of their attitudes comparing with the previous methodology. Learners had left some feedbacks that collaborative learning should be applied to other courses.

  8. Modeling of phosphorus fluxes produced by wild fires at watershed scales.

    Science.gov (United States)

    Matyjasik, M.; Hernandez, M.; Shaw, N.; Baker, M.; Fowles, M. T.; Cisney, T. A.; Jex, A. P.; Moisen, G.

    2017-12-01

    River runoff is one of the controlling processes in the terrestrial phosphorus cycle. Phosphorus is often a limiting factor in fresh water. One of the factors that has not been studied and modeled in detail is phosporus flux produced from forest wild fires. Phosphate released by weathering is quickly absorbed in soils. Forest wild fires expose barren soils to intensive erosion, thus releasing relatively large fluxes of phosphorus. Measurements from three control burn sites were used to correlate erosion with phosphorus fluxes. These results were used to model phosphorus fluxes from burned watersheds during a five year long period after fires occurred. Erosion in our model is simulated using a combination of two models: the WEPP (USDA Water Erosion Prediction Project) and the GeoWEPP (GIS-based Water Erosion Prediction Project). Erosion produced from forest disturbances is predicted for any watershed using hydrologic, soil, and meteorological data unique to the individual watersheds or individual slopes. The erosion results are modified for different textural soil classes and slope angles to model fluxes of phosphorus. The results of these models are calibrated using measured concentrations of phosphorus for three watersheds located in the Interior Western United States. The results will help the United States Forest Service manage phosporus fluxes in national forests.

  9. Sodium spray and jet fire model development within the CONTAIN-LMR code

    International Nuclear Information System (INIS)

    Scholtyssek, W.

    1993-01-01

    An assessment was made of the sodium spray fire model implemented in the CONTAIN code. The original droplet burn model, which was based on the NACOM code, was improved in several aspects, especially concerning evaluation of the droplet burning rate, reaction chemistry and heat balance, spray geometry and droplet motion, and consistency with CONTAIN standards of gas property evaluation. An additional droplet burning model based on a proposal by Krolikowski was made available to include the effect of the chemical equilibrium conditions at the flame temperature. The models were validated against single-droplet burn experiments as well as spray and jet fire experiments. Reasonable agreement was found between the two burn models and experimental data. When the gas temperature in the burning compartment reaches high values, the Krolikowski model seems to be preferable. Critical parameters for spray fire evaluation were found to be the spray characterization, especially the droplet size, which largely determines the burning efficiency, and heat transfer conditions at the interface between the atmosphere and structures, which controls the thermal hydraulic behavior in the burn compartment

  10. An Integrated Model for Identifying Linkages Between the Management of Fuel Treatments, Fire and Ecosystem Services

    Science.gov (United States)

    Bart, R. R.; Anderson, S.; Moritz, M.; Plantinga, A.; Tague, C.

    2015-12-01

    Vegetation fuel treatments (e.g. thinning, prescribed burning) are a frequent tool for managing fire-prone landscapes. However, predicting how fuel treatments may affect future wildfire risk and associated ecosystem services, such as forest water availability and streamflow, remains a challenge. This challenge is in part due to the large range of conditions under which fuel treatments may be implemented, as response is likely to vary with species type, rates of vegetation regrowth, meteorological conditions and physiographic properties of the treated site. It is also due to insufficient understanding of how social factors such as political pressure, public demands and economic constraints affect fuel management decisions. To examine the feedbacks between ecological and social dimensions of fuel treatments, we present an integrated model that links a biophysical model that simulates vegetation and hydrology (RHESSys), a fire spread model (WMFire) and an empirical fuel treatment model that accounts for agency decision-making. We use this model to investigate how management decisions affect landscape fuel loads, which in turn affect fire severity and ecosystem services, which feedback to management decisions on fuel treatments. We hypothesize that this latter effect will be driven by salience theory, which predicts that fuel treatments are more likely to occur following major wildfire events. The integrated model provides a flexible framework for answering novel questions about fuel treatments that span social and ecological domains, areas that have previously been treated separately.

  11. The birth of a collaborative model: obstetricians, midwives, and family physicians.

    Science.gov (United States)

    Pecci, Christine Chang; Mottl-Santiago, Julie; Culpepper, Larry; Heffner, Linda; McMahan, Therese; Lee-Parritz, Aviva

    2012-09-01

    In the United States, the challenges of maternity care include provider workforce, cost containment, and equal access to quality care. This article describes a collaborative model of care involving midwives, family physicians, and obstetricians at the Boston Medical Center, which serves a low-income multicultural population. Leadership investment in a collaborative model of care from the Department of Obstetrics and Gynecology, Section of Midwifery, and the Department of Family Medicine created a culture of safety and commitment to patient-centered care. Essential elements of the authors' successful model include a commitment to excellence in patient care, communication, and interdisciplinary education. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Context-Aware Mobile Collaborative Systems: Conceptual Modeling and Case Study

    Directory of Open Access Journals (Sweden)

    Luis G. Montané-Jiménez

    2012-10-01

    Full Text Available A Mobile Collaborative System (MCOS enable the cooperation of the members of a team to achieve a common goal by using a combination of mobile and fixed technologies. MCOS can be enhanced if the context of the group of users is considered in the execution of activities. This paper proposes a novel model for Context-Aware Mobile COllaborative Systems (CAMCOS and a functional architecture based on that model. In order to validate both the model and the architecture, a prototype system in the tourism domain was implemented and evaluated.

  13. Fuzzy comprehensive evaluation model of interuniversity collaborative learning based on network

    Science.gov (United States)

    Wenhui, Ma; Yu, Wang

    2017-06-01

    Learning evaluation is an effective method, which plays an important role in the network education evaluation system. But most of the current network learning evaluation methods still use traditional university education evaluation system, which do not take into account of web-based learning characteristics, and they are difficult to fit the rapid development of interuniversity collaborative learning based on network. Fuzzy comprehensive evaluation method is used to evaluate interuniversity collaborative learning based on the combination of fuzzy theory and analytic hierarchy process. Analytic hierarchy process is used to determine the weight of evaluation factors of each layer and to carry out the consistency check. According to the fuzzy comprehensive evaluation method, we establish interuniversity collaborative learning evaluation mathematical model. The proposed scheme provides a new thought for interuniversity collaborative learning evaluation based on network.

  14. Fuzzy comprehensive evaluation model of interuniversity collaborative learning based on network

    Directory of Open Access Journals (Sweden)

    Wenhui Ma

    2017-06-01

    Full Text Available Learning evaluation is an effective method, which plays an important role in the network education evaluation system. But most of the current network learning evaluation methods still use traditional university education evaluation system, which do not take into account of web-based learning characteristics, and they are difficult to fit the rapid development of interuniversity collaborative learning based on network. Fuzzy comprehensive evaluation method is used to evaluate interuniversity collaborative learning based on the combination of fuzzy theory and analytic hierarchy process. Analytic hierarchy process is used to determine the weight of evaluation factors of each layer and to carry out the consistency check. According to the fuzzy comprehensive evaluation method, we establish interuniversity collaborative learning evaluation mathematical model. The proposed scheme provides a new thought for interuniversity collaborative learning evaluation based on network.

  15. An Accurate Fire-Spread Algorithm in the Weather Research and Forecasting Model Using the Level-Set Method

    Science.gov (United States)

    Muñoz-Esparza, Domingo; Kosović, Branko; Jiménez, Pedro A.; Coen, Janice L.

    2018-04-01

    The level-set method is typically used to track and propagate the fire perimeter in wildland fire models. Herein, a high-order level-set method using fifth-order WENO scheme for the discretization of spatial derivatives and third-order explicit Runge-Kutta temporal integration is implemented within the Weather Research and Forecasting model wildland fire physics package, WRF-Fire. The algorithm includes solution of an additional partial differential equation for level-set reinitialization. The accuracy of the fire-front shape and rate of spread in uncoupled simulations is systematically analyzed. It is demonstrated that the common implementation used by level-set-based wildfire models yields to rate-of-spread errors in the range 10-35% for typical grid sizes (Δ = 12.5-100 m) and considerably underestimates fire area. Moreover, the amplitude of fire-front gradients in the presence of explicitly resolved turbulence features is systematically underestimated. In contrast, the new WRF-Fire algorithm results in rate-of-spread errors that are lower than 1% and that become nearly grid independent. Also, the underestimation of fire area at the sharp transition between the fire front and the lateral flanks is found to be reduced by a factor of ≈7. A hybrid-order level-set method with locally reduced artificial viscosity is proposed, which substantially alleviates the computational cost associated with high-order discretizations while preserving accuracy. Simulations of the Last Chance wildfire demonstrate additional benefits of high-order accurate level-set algorithms when dealing with complex fuel heterogeneities, enabling propagation across narrow fuel gaps and more accurate fire backing over the lee side of no fuel clusters.

  16. Large Scale Experiments on Spacecraft Fire Safety

    Science.gov (United States)

    Urban, David; Ruff, Gary A.; Minster, Olivier; Fernandez-Pello, A. Carlos; Tien, James S.; Torero, Jose L.; Legros, Guillaume; Eigenbrod, Christian; Smirnov, Nickolay; Fujita, Osamu; hide

    2012-01-01

    Full scale fire testing complemented by computer modelling has provided significant knowhow about the risk, prevention and suppression of fire in terrestrial systems (cars, ships, planes, buildings, mines, and tunnels). In comparison, no such testing has been carried out for manned spacecraft due to the complexity, cost and risk associated with operating a long duration fire safety experiment of a relevant size in microgravity. Therefore, there is currently a gap in knowledge of fire behaviour in spacecraft. The entire body of low-gravity fire research has either been conducted in short duration ground-based microgravity facilities or has been limited to very small fuel samples. Still, the work conducted to date has shown that fire behaviour in low-gravity is very different from that in normal gravity, with differences observed for flammability limits, ignition delay, flame spread behaviour, flame colour and flame structure. As a result, the prediction of the behaviour of fires in reduced gravity is at present not validated. To address this gap in knowledge, a collaborative international project, Spacecraft Fire Safety, has been established with its cornerstone being the development of an experiment (Fire Safety 1) to be conducted on an ISS resupply vehicle, such as the Automated Transfer Vehicle (ATV) or Orbital Cygnus after it leaves the ISS and before it enters the atmosphere. A computer modelling effort will complement the experimental effort. Although the experiment will need to meet rigorous safety requirements to ensure the carrier vehicle does not sustain damage, the absence of a crew removes the need for strict containment of combustion products. This will facilitate the possibility of examining fire behaviour on a scale that is relevant to spacecraft fire safety and will provide unique data for fire model validation. This unprecedented opportunity will expand the understanding of the fundamentals of fire behaviour in spacecraft. The experiment is being

  17. Computational fluid dynamics (CFD) modelling of coal/biomass co-firing in pulverised fuel boilers

    Energy Technology Data Exchange (ETDEWEB)

    Moghtaderi, B.; Meesri, C. [University of Newcastle, Callaghan, NSW (Australia). CRC for Coal in Sustainable Development, Dept. of Chemical Engineering

    2002-07-01

    The present study is concerned with computational fluid dynamics (CFD) modelling of coal/biomass blends co-fired under conditions pertinent to pulverised fuel (PF) boilers. The attention is particularly focused on the near burner zone to examine the impact of biomass on the flame geometry and temperature. The predictions are obtained by numerical solution of the conservation equations for the gas and particle phases. The gas phase is solved in the Eulerian domain using steady-state time-averaged Navier-Stokes equations while the solution of the particle phase is obtained from a series of Lagrangian particle tracking equations. Turbulence is modelled using the {kappa}-{epsilon} and Reynolds Stress models. The comparison between the predictions and experimental measurement reported in the literature resulted in a good agreement. Other influences of biomass co-firing are observed for fuel devolatilisation and burnout. 19 refs., 6 figs.

  18. WeedML: a Tool for Collaborative Weed Demographic Modeling

    OpenAIRE

    Holst, Niels

    2010-01-01

    WeedML is a proposed standard to formulate models of weed demography, or maybe even complex models in general, that are both transparent and straightforward to re-use as building blocks for new models. The paper describes the design and thoughts behind WeedML which relies on XML and object-oriented systems development. Proof-of-concept software is provided as open-source C++ code and executables that can be downloaded freely.

  19. Collaborative Economy

    DEFF Research Database (Denmark)

    collaborative economy and tourism Dianne Dredge and Szilvia Gyimóthy PART I - Theoretical explorations 2.Definitions and mapping the landscape in the collaborative economy Szilvia Gyimóthy and Dianne Dredge 3.Business models of the collaborative economy Szilvia Gyimóthy 4.Responsibility and care...... and similar phenomena are among these collective innovations in tourism that are shaking the very bedrock of an industrial system that has been traditionally sustained along commercial value chains. To date there has been very little investigation of these trends, which have been inspired by, amongst other...... in the collaborative economy Dianne Dredge 5.Networked cultures in the collaborative economy Szilvia Gyimóthy 6.Policy and regulatory perspectives in the collaborative economy Dianne Dredge PART II - Disruptions, innovations and transformations 7.Regulating innovation in the collaborative economy: An examination...

  20. Motives and preferences of general practitioners for new collaboration models with medical specialists: a qualitative study

    Directory of Open Access Journals (Sweden)

    Klazinga Niek S

    2007-01-01

    Full Text Available Abstract Background Collaboration between general practitioners (GPs and specialists has been the focus of many collaborative care projects during the past decade. Unfortunately, quite a number of these projects failed. This raises the question of what motivates GPs to initiate and continue participating with medical specialists in new collaborative care models. The following two questions are addressed in this study: What motivates GPs to initiate and sustain new models for collaborating with medical specialists? What kind of new collaboration models do GPs suggest? Methods A qualitative study design was used. Starting in 2003 and finishing in 2005, we conducted semi-structured interviews with a purposive sample of 21 Dutch GPs. The sampling criteria were age, gender, type of practice, and practice site. The interviews were recorded, fully transcribed, and analysed by two researchers working independently. The resulting motivational factors and preferences were grouped into categories. Results 'Developing personal relationships' and 'gaining mutual respect' appeared to dominate when the motivational factors were considered. Besides developing personal relationships with specialists, the GPs were also interested in familiarizing specialists with the competencies attached to the profession of family medicine. Additionally, they were eager to increase their medical knowledge to the benefit of their patients. The GPs stated a variety of preferences with respect to the design of new models of collaboration. Conclusion Developing personal relationships with specialists appeared to be one of the dominant motives for increased collaboration. Once the relationships have been formed, an informal network with occasional professional contact seemed sufficient. Although GPs are interested in increasing their knowledge, once they have reached a certain level of expertise, they shift their focus to another specialty. The preferences for new collaboration