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Sample records for plant simulation system

  1. Design and simulation of a plant control system for a GCFR demonstration plant

    SciTech Connect

    Estrine, E.A.; Greiner, H.G.

    1980-02-01

    A plant control system is being designed for a 300 MW(e) Gas Cooled Fast Breeder Reactor (GCFR) demonstration plant. Control analysis is being performed as an integral part of the plant design process to ensure that control requirements are satisfied as the plant design evolves. Plant models and simulations are being developed to generate information necessary to further define control system requirements for subsequent plant design iterations.

  2. Gravisensitivity of various host plant -virus systems in simulated microgravity

    NASA Astrophysics Data System (ADS)

    Mishchenko, Lidiya; Taran, Oksana; Gordejchyk, Olga

    In spite of considerable achievements in the study of gravity effects on plant development, some issues of gravitropism, like species-specificity and gravitation response remain unclear. The so-lution of such problems is connected with the aspects of life supply, in piloted space expeditions. The role of microgravity remains practically unstudied in the development of relations in the system host plant-virus, which are important for biotechnologies in crop production. It is ev-ident that the conditions of space flight can act as stressors, and the stress inducted by them favors the reactivation of latest herpes viruses in humans (satish et al., 2009) Viral infections of plants, which also can be in a latest state at certain stages of plant organism development, cause great damage to the growth and development of a host plant. Space flight conditions may cause both reactivation of latent viral infection in plants and its elimination, as it has been found by us for the system WSMW -wheat (Mishchenko et al., 2004). Our further research activities were concentrated on the identification of gravisensitivity in the system virus -potato plant to find out whether there was any species -related specificity of the reaction. In our research we used potato plants of Krymska Rosa, Zhuravushka, Agave, Belarosa, Kupalinka, and Zdubytok varieties. Simulated microgravity was ensured by clinostats KG-8 and Cycle -2. Gravisensitiv-ity has been studied the systems including PVX, PVM and PVY. Virus concentrations have been determined by ELISA using LOEWE reagents (placecountry-regionGermany). Virus iden-tification by morphological features were done by electron microscopy. For the system PVX -potato plant, we found the reduction in virus antigens content with prolonged clinostating. On the 18th day of cultivation, the plants showed a high level of X-virus antigen content on both stationary (control) and clinostated variants. On 36th and 47th day, depending plant variety, clinostated

  3. Simulated coal gas MCFC power plant system verification

    SciTech Connect

    1998-02-01

    The following tasks are included in this project: Commercialization; Power plant development; Manufacturing facilities development; Test facility development; Stack research; and Advanced research and technology development. This report briefly describes the subtasks still to be completed: Power plant system test with reformed natural gas; Upgrading of existing, US government-owned, test facilities; and Advanced MCFC component research.

  4. Simulated coal gas MCFC power plant system verification

    SciTech Connect

    Benjamin, T.G.; Camara, E.H.; Laurens, R.; Marianowski, L.G.

    1992-01-01

    The overall program objective is the demonstration of a full-scale, full-height IMHEX {reg sign} molten carbonate fuel cell stack in a 250 kW dual-fuel power plant test on natural gas and simulated coal gas. Issues impeding development of manufacturing and testing facilities will be addressed in support of MCFC stack research and power plant development. Issues will be identified and resolved in engineering, manufacturing, assembling, cost, performance, and endurance of the stack repeat and non-repeat components. The program is being executed by M-C Power (MCP) and several major subcontractors.

  5. Simulated coal gas MCFC power plant system verification

    SciTech Connect

    Benjamin, T.G.; Camara, E.H.; Laurens, R.; Marianowski, L.G.

    1992-09-01

    The overall program objective is the demonstration of a full-scale, full-height IMHEX {reg_sign} molten carbonate fuel cell stack in a 250 kW dual-fuel power plant test on natural gas and simulated coal gas. Issues impeding development of manufacturing and testing facilities will be addressed in support of MCFC stack research and power plant development. Issues will be identified and resolved in engineering, manufacturing, assembling, cost, performance, and endurance of the stack repeat and non-repeat components. The program is being executed by M-C Power (MCP) and several major subcontractors.

  6. Simulation model for plant growth in controlled environment systems

    NASA Technical Reports Server (NTRS)

    Raper, C. D., Jr.; Wann, M.

    1986-01-01

    The role of the mathematical model is to relate the individual processes to environmental conditions and the behavior of the whole plant. Using the controlled-environment facilities of the phytotron at North Carolina State University for experimentation at the whole-plant level and methods for handling complex models, researchers developed a plant growth model to describe the relationships between hierarchial levels of the crop production system. The fundamental processes that are considered are: (1) interception of photosynthetically active radiation by leaves, (2) absorption of photosynthetically active radiation, (3) photosynthetic transformation of absorbed radiation into chemical energy of carbon bonding in solube carbohydrates in the leaves, (4) translocation between carbohydrate pools in leaves, stems, and roots, (5) flow of energy from carbohydrate pools for respiration, (6) flow from carbohydrate pools for growth, and (7) aging of tissues. These processes are described at the level of organ structure and of elementary function processes. The driving variables of incident photosynthetically active radiation and ambient temperature as inputs pertain to characterization at the whole-plant level. The output of the model is accumulated dry matter partitioned among leaves, stems, and roots; thus, the elementary processes clearly operate under the constraints of the plant structure which is itself the output of the model.

  7. Simulated coal gas MCFC power plant system verification. Final report

    SciTech Connect

    1998-07-30

    The objective of the main project is to identify the current developmental status of MCFC systems and address those technical issues that need to be resolved to move the technology from its current status to the demonstration stage in the shortest possible time. The specific objectives are separated into five major tasks as follows: Stack research; Power plant development; Test facilities development; Manufacturing facilities development; and Commercialization. This Final Report discusses the M-C power Corporation effort which is part of a general program for the development of commercial MCFC systems. This final report covers the entire subject of the Unocal 250-cell stack. Certain project activities have been funded by organizations other than DOE and are included in this report to provide a comprehensive overview of the work accomplished.

  8. A graphical user interface for design, simulation and analysis of power plant electrical auxiliary systems

    SciTech Connect

    Yu, D.C.; Jamal, N.; Wang, W.; Zhang, X.G. ); Brandt, J.R. )

    1994-06-01

    An interactive Graphical User Interface (GUI) package for the design, simulation and analysis of a power plant electrical auxiliary system is presented in this paper. The purpose of this package is to assist the engineer in performing non real-time, what-if, analysis in an interactive and intuitive environment. The package, AUXSYS, is capable of performing load flow and motor starting simulations. It provides a graphical interface for designing the one-line diagram of the plant and analyzing the output of the simulations. It is currently used for modeling Wisconsin Electric Power Company's (WEPCO) power plant electrical auxiliary systems and is implemented for use on PC's.

  9. LWR (Light Water Reactor) power plant simulations using the AD10 and AD100 systems

    SciTech Connect

    Wulff, W.; Cheng, H.S.; Chien, C.J.; Jang, J.Y.; Lin, H.C.; Mallen, A.N.; Wang, S.J.; Institute of Nuclear Energy Research, Lung-Tan; Tawian Power Co., Taipei; Brookhaven National Lab., Upton, NY; Institute of Nuclear Energy Research, Lung-Tan )

    1989-01-01

    Boiling (BWR) and Pressurized (PWR) Water Reactor Power Plants are being simulated at BNL with the AD10 and AD100 Peripheral Processor Systems. The AD10 system has been used for BWR simulations since 1984 for safety analyses, emergency training and optimization studies. BWR simulation capabilities have been implemented recently on the AD100 system and PWR simulation capabilities are currently being developed under the auspices of international cooperation. Modeling and simulation methods are presented with emphasis on the simulation of the Nuclear Steam Supply System. Results are presented for BWR simulation and performance characteristics are compared of the AD10 and AD100 systems. It will be shown that the AD100 simulates two times faster than two AD10 processors operating in parallel and that the computing capacity of one AD100 (with FMU processor) is twice as large as that of two AD10 processors. 9 refs., 5 figs., 1 tab.

  10. Simulated coal gas MCFC power plant system verification

    SciTech Connect

    1998-01-01

    This technical progress report summarizes the objectives and progress on the following tasks associated with the project: Commercialization; Power plant development; Manufacturing facilities development; Testing facility development; Stack research; and Advanced research and technology development. The project will demonstrate a 250 kW molten carbonate fuel cell power plant based on the IMHEX stack design concept.

  11. SIMULATED COAL GAS MCFC POWER PLANT SYSTEM VERIFICATION

    SciTech Connect

    J.A. Scroppo

    1998-07-01

    This is the Technical Progress Report covering June 1998. All tasks have been completed, except for those discussed on the following pages. Unocal estimated the costs of dismantling and packaging the test facility for storage and shipment. The scope of work for the contract has been modified to accommodate the dismantling and packaging of the plant. An amendment to Sub-Contract No. MCP-9-UNO between M-C Power and Unocal has been executed which includes the Scope of Work in Unocal's cost estimate.

  12. SIMULATED COAL GAS MCFC POWER PLANT SYSTEM VERIFICATION

    SciTech Connect

    1998-10-31

    This is the Technical Progress Report covering October 1998. All tasks have been completed, except for those discussed on the following pages. Unocal estimated the costs of dismantling and packaging the test facility for storage and shipment. The scope of work for the contract has been modified to accommodate the dismantling and packaging of the plant. An amendment to Sub-Contract No. MCP-9-UNO between M-C Power and Unocal has been executed which includes the Scope of Work in Unocal's cost estimate.

  13. System Simulation of Nuclear Power Plant by Coupling RELAP5 and Matlab/Simulink

    SciTech Connect

    Meng Lin; Dong Hou; Zhihong Xu; Yanhua Yang; Ronghua Zhang

    2006-07-01

    Since RELAP5 code has general and advanced features in thermal-hydraulic computation, it has been widely used in transient and accident safety analysis, experiment planning analysis, and system simulation, etc. So we wish to design, analyze, verify a new Instrumentation And Control (I and C) system of Nuclear Power Plant (NPP) based on the best-estimated code, and even develop our engineering simulator. But because of limited function of simulating control and protection system in RELAP5, it is necessary to expand the function for high efficient, accurate, flexible design and simulation of I and C system. Matlab/Simulink, a scientific computation software, just can compensate the limitation, which is a powerful tool in research and simulation of plant process control. The software is selected as I and C part to be coupled with RELAP5 code to realize system simulation of NPPs. There are two key techniques to be solved. One is the dynamic data exchange, by which Matlab/Simulink receives plant parameters and returns control results. Database is used to communicate the two codes. Accordingly, Dynamic Link Library (DLL) is applied to link database in RELAP5, while DLL and S-Function is applied in Matlab/Simulink. The other problem is synchronization between the two codes for ensuring consistency in global simulation time. Because Matlab/Simulink always computes faster than RELAP5, the simulation time is sent by RELAP5 and received by Matlab/Simulink. A time control subroutine is added into the simulation procedure of Matlab/Simulink to control its simulation advancement. Through these ways, Matlab/Simulink is dynamically coupled with RELAP5. Thus, in Matlab/Simulink, we can freely design control and protection logic of NPPs and test it with best-estimated plant model feedback. A test will be shown to illuminate that results of coupling calculation are nearly the same with one of single RELAP5 with control logic. In practice, a real Pressurized Water Reactor (PWR) is

  14. Pellet plant energy simulator

    NASA Astrophysics Data System (ADS)

    Bordeasu, D.; Vasquez Pulido, T.; Nielsen, C.

    2016-02-01

    The Pellet Plant energy simulator is a software based on advanced algorithms which has the main purpose to see the response of a pellet plant regarding certain location conditions. It combines energy provided by a combined heat and power, and/or by a combustion chamber with the energy consumption of the pellet factory and information regarding weather conditions in order to predict the biomass consumption of the pellet factory together with the combined heat and power, and/or with the biomass consumption of the combustion chamber. The user of the software will not only be able to plan smart the biomass acquisition and estimate its cost, but also to plan smart the preventive maintenance (charcoal cleaning in case of a gasification plant) and use the pellet plant at the maximum output regarding weather conditions and biomass moisture. The software can also be used in order to execute a more precise feasibility study for a pellet plant in a certain location. The paper outlines the algorithm that supports the Pellet Plant Energy Simulator idea and presents preliminary tests results that supports the discussion and implementation of the system

  15. Generation of a modeling and simulation system for a semi-closed plant growth chamber

    NASA Technical Reports Server (NTRS)

    Blackwell, A. L.; Maa, S.; Kliss, M.; Blackwell, C. C.

    1993-01-01

    The fluid and thermal dynamics of the environment of plants in a small controlled-environment system have been modeled. The results of the simulation under two scenarios have been compared to measurements taken during tests on the actual system. The motivation for the modeling effort and the status of the modeling exercise and system scenario studies are described. An evaluation of the model and a discussion of future studies are included.

  16. Design, simulation, analysis and optimization of transportation system for a biomass to ethanol conversion plant

    NASA Astrophysics Data System (ADS)

    Ravula, Poorna P.

    The US Department of Energy has set an ambitious goal of replacing 30% of current petroleum consumption with biomass and its products by the year 2030. To achieve this goal, various systems capable of handling biomass at this magnitude have to be designed and built. The transportation system for a cotton gin was studied and modeled with the current management policy (FIFO) used by the gin to gain understanding of a logistic system where the processing plant (gin) pays for the transportation of the feedstock. Alternate management policies for transporting cotton modules showed significant time savings of 24% in days-to-haul. To design a logistics system and management strategy that will minimize the cost of biomass delivery (round bales of switchgrass), a seven-county region in southern Piedmont region of Virginia was selected as the location for a 50 Mg/h bioprocessing plant which operates 24 h/day, 7 days/week. Some of the equipment are not be commercially available and need to be developed. The transport equipment (trucks, loaders and unloaders) was defined and the operational parameters estimated. One hundred and fifty-five secondary storage locations (SSLs) along with a 3.2-km procurement area for each SSL were determined for the region. The travel time from each SSL to the plant was calculated based on a network flow analysis. Seven different policies (strategies) for scheduling loaders were studied. The two key variables were maximum number of trucks required and the maximum at-plant inventory. Five policies were based on "Shortest Travel Time - Longest Travel Time" allocation and two policies were based on "Sector-based" allocation. Policies generating schedules with minimum truck requirement and at-plant storage were simulated. A discrete event simulation model for the logistic system was constructed and the productive operating times for system equipment and inventory was computed. Lowest delivered cost was 14.68/Mg with truck cost averaging 8.44/Mg and

  17. Simulation of the flue gas cleaning system of an RDF incineration power plant.

    PubMed

    Jannelli, E; Minutillo, M

    2007-01-01

    Because of the stringent pollutant emission standards introduced with the European Union guidelines for waste incineration, it is very important to optimize the flue gas cleaning systems which are able to result in a low environmental impact according to the emission limits. In this paper a thermochemical model has been proposed for the simulation of the flue gas cleaning system of an RDF incineration plant. The model simulates the operation of the flue-gas treatment section and the combustion section by using a simplified approach. The combustion includes the grate incinerator and the post-combustion chamber, while the cleaning section includes the NO(x) reduction process (urea injection) and the scrubbing of SO(2) and HCl (Ca(OH)(2) as sorbent). The modelling has been conducted by means of ASPEN PLUS code. The simulation results have been validated with the operating data. The model proposed by the authors can be a useful tool in both evaluating the efficiency of the gas cleaning system by verifying the environmental pollution of an incinerator power plant in nominal operating conditions and in forecasting the efficiency of the cleaning system in off-design operating conditions. PMID:16750619

  18. Governor stability simulations of Svartisen power plant verified by the installed monitoring system on site

    NASA Astrophysics Data System (ADS)

    Nielsen, T. K.; Kjeldsen, M.

    2010-08-01

    Many Norwegian hydro power plants have complex lay-out with several reservoirs, broke intakes, surge shafts and even air cushion chambers. There are kilometers of excavated tunnels as well as long tail water systems. The stations are often equipped by multiple of turbines, both in series and parallel. A number of operation modes are therefore possible. Doing transient simulations and simulations of governor stability in the design phase, the problem is to find the worst case scenario regarding these operating modes. Svartisen power plant has been of particular interest these days. The power plant is originally designed for two 350 MW Francis turbines, however, only one turbine was installed. When designed, governor stability was regarded as problematic due to the long penstock. A long penstock will give a too high time constant for the hydraulic inertia. The main problem here is, however, the water hammer frequency that interferes with the governor performance. The frequency is in the same range as the cross frequency. Therefore the governor will react on these water hammer waves, which in its nature is notoriously unstable. The common solution is to build an air cushion and thereby increase the water hammer frequency above the cross frequency. The expenses were, however, deemed too high, and it was necessary to seek for other solutions. A pressure feedback on the governor was introduced in order to have stable operation at least for two turbines. With only one turbine installed, the pressure feedback has not been activated because, based on the simulations, it was regarded unnecessary. Even if the original simulations shows good stability margins when only one turbine is running, there has been some indications that the aggregate has suffered from instability. In 2004 Svartisen Power Plant was equipped with a comprehensive monitoring system. Both the turbine and the generator performance have been observed. This gives valuable information on how the hydropower

  19. Assessment of solar options for small power systems applications. Volume V. SOLSTEP: a computer model for solar plant system simulations

    SciTech Connect

    Bird, S.P.

    1980-09-01

    The simulation code, SOLSTEP, was developed at the Pacific Northwest Laboratory to facilitate the evaluation of proposed designs for solar thermal power plants. It allows the user to analyze the thermodynamic and economic performance of a conceptual design for several field size-storage capacity configurations. This feature makes it possible to study the levelized energy cost of a proposed concept over a range of plant capacity factors. The thermodynamic performance is analyzed on a time step basis using actual recorded meteorological and insolation data for specific geographic locations. The flexibility of the model enables the user to analyze both central and distributed generation concepts using either thermal or electric storage systems. The thermodynamic and economic analyses view the plant in a macroscopic manner as a combination of component subsystems. In the thermodynamic simulation, concentrator optical performance is modeled as a function of solar position; other aspects of collector performance can optionally be treated as functions of ambient air temperature, wind speed, and component power level. The power conversion model accounts for the effects of ambient air temperature, partial load operation, auxiliary power demands, and plant standby and startup energy requirements. The code was designed in a modular fashion to provide efficient evaluations of the collector system, total plant, and system economics. SOLSTEP has been used to analyze a variety of solar thermal generic concepts involving several collector types and energy conversion and storage subsystems. The code's straightforward models and modular nature facilitated simple and inexpensive parametric studies of solar thermal power plant performance.

  20. GCFR plant control system

    SciTech Connect

    Estrine, E.A.; Greiner, H.G.

    1980-05-01

    A plant control system is being designed for a gas-cooled fast breeder reactor (GCFR) demonstration plant. Control analysis is being performed as an integral part of the plant design process to ensure that control requirements are satisfied as the plant design evolves. The load control portion of the plant control system provides stable automatic (closed-loop) control of the plant over the 25% to 100% load range. Simulation results are presented to demonstrate load control system performance. The results show that the plant is controllable at full load with the control system structure selected, but gain scheduling is required to achieve desired performance over the load range.

  1. A simulation methodology to evaluate BIG-STIG systems in sugar and alcohol plants

    SciTech Connect

    Walter, A.C.; Bajay, S.V.; Nogueira, L.A.H.

    1994-12-31

    This paper describes a simulation procedure to assess BIG-STIG -- Biomass Integrated Gasifier/Steam Injected Gas Turbine -- systems in sugar-cane mills. Two configurations are considered: one in which the conventional steam cycle is the bottoming part of a combined cycle and another one in which the gas turbine is used as the only power machine. Both the operation during the harvest season and the operation between such seasons -- when the steam injection in the gas turbines occurs -- are simulated. The four main modules of a BIG-STIG system are simulated here: the gas turbine -- GT, the heat recovery steam generator -- HRSG, the biomass gasification plant and the conventional back-pressure steam turbine cogeneration unit. Three gas turbines of different capacities were studied and the corresponding results compared to those available in some references. The modelling allows the analysis of the process steam requirements, the blast air extractions and the main HRSG operational constraints, like the minimum pinch-point temperature at the HRSG and the minimum HRSG stack gas value.

  2. Dynamic Simulation Nuclear Power Plants

    Energy Science and Technology Software Center (ESTSC)

    1992-03-03

    DSNP (Dynamic Simulator for Nuclear Power-Plants) is a system of programs and data files by which a nuclear power plant, or part thereof, can be simulated. The acronym DSNP is used interchangeably for the DSNP language, the DSNP libraries, the DSNP precompiler, and the DSNP document generator. The DSNP language is a special-purpose, block-oriented, digital-simulation language developed to facilitate the preparation of dynamic simulations of a large variety of nuclear power plants. It is amore » user-oriented language that permits the user to prepare simulation programs directly from power plant block diagrams and flow charts by recognizing the symbolic DSNP statements for the appropriate physical components and listing these statements in a logical sequence according to the flow of physical properties in the simulated power plant. Physical components of nuclear power plants are represented by functional blocks, or modules. Many of the more complex components are represented by several modules. The nuclear reactor, for example, has a kinetic module, a power distribution module, a feedback module, a thermodynamic module, a hydraulic module, and a radioactive heat decay module. These modules are stored in DSNP libraries in the form of a DSNP subroutine or function, a block of statements, a macro, or a combination of the above. Basic functional blocks such as integrators, pipes, function generators, connectors, and many auxiliary functions representing properties of materials used in nuclear power plants are also available. The DSNP precompiler analyzes the DSNP simulation program, performs the appropriate translations, inserts the requested modules from the library, links these modules together, searches necessary data files, and produces a simulation program in FORTRAN.« less

  3. Development of the simulation system {open_quotes}IMPACT{close_quotes} for analysis of nuclear power plant severe accidents

    SciTech Connect

    Naitoh, Masanori; Ujita, Hiroshi; Nagumo, Hiroichi

    1997-07-01

    The Nuclear Power Engineering Corporation (NUPEC) has initiated a long-term program to develop the simulation system {open_quotes}IMPACT{close_quotes} for analysis of hypothetical severe accidents in nuclear power plants. IMPACT employs advanced methods of physical modeling and numerical computation, and can simulate a wide spectrum of senarios ranging from normal operation to hypothetical, beyond-design-basis-accident events. Designed as a large-scale system of interconnected, hierarchical modules, IMPACT`s distinguishing features include mechanistic models based on first principles and high speed simulation on parallel processing computers. The present plan is a ten-year program starting from 1993, consisting of the initial one-year of preparatory work followed by three technical phases: Phase-1 for development of a prototype system; Phase-2 for completion of the simulation system, incorporating new achievements from basic studies; and Phase-3 for refinement through extensive verification and validation against test results and available real plant data.

  4. Coal Preparation Plant Simulation

    Energy Science and Technology Software Center (ESTSC)

    1992-02-25

    COALPREP assesses the degree of cleaning obtained with different coal feeds for a given plant configuration and mode of operation. It allows the user to simulate coal preparation plants to determine an optimum plant configuration for a given degree of cleaning. The user can compare the performance of alternative plant configurations as well as determine the impact of various modes of operation for a proposed configuration. The devices that can be modelled include froth flotationmore » devices, washers, dewatering equipment, thermal dryers, rotary breakers, roll crushers, classifiers, screens, blenders and splitters, and gravity thickeners. The user must specify the plant configuration and operating conditions and a description of the coal feed. COALPREP then determines the flowrates within the plant and a description of each flow stream (i.e. the weight distribution, percent ash, pyritic sulfur and total sulfur, moisture, BTU content, recoveries, and specific gravity of separation). COALPREP also includes a capability for calculating the cleaning cost per ton of coal.« less

  5. Coal Preparation Plant Simulation

    Energy Science and Technology Software Center (ESTSC)

    1992-02-25

    COALPREP assesses the degree of cleaning obtained with different coal feeds for a given plant configuration and mode of operation. It allows the user to simulate coal preparation plants to determine an optimum plant configuration for a given degree of cleaning. The user can compare the performance of alternative plant configurations as well as determine the impact of various modes of operation for a proposed configuration. The devices that can be modelled include froth flotationmore » devices, washers, dewatering equipment, thermal dryers, rotary breakers, roll crushers, classifiers, screens, blenders and splitters, and gravity thickeners. The user must specify the plant configuration and operating conditions and a description of the coal feed. COALPREP then determines the flowrates within the plant and a description of each flow stream (i.e. the weight distribution, percent ash, pyritic sulfur and total sulfur, moisture, BTU content, recoveries, and specific gravity of separation). COALPREP also includes a capability for calculating the cleaning cost per ton of coal. The IBM PC version contains two auxiliary programs, DATAPREP and FORLIST. DATAPREP is an interactive preprocessor for creating and editing COALPREP input data. FORLIST converts carriage-control characters in FORTRAN output data to ASCII line-feed (X''0A'') characters.« less

  6. Partial automation of database processing of simulation outputs from L-systems models of plant morphogenesis.

    PubMed

    Chen, Yi- Ping Phoebe; Hanan, Jim

    2002-01-01

    Models of plant architecture allow us to explore how genotype environment interactions effect the development of plant phenotypes. Such models generate masses of data organised in complex hierarchies. This paper presents a generic system for creating and automatically populating a relational database from data generated by the widely used L-system approach to modelling plant morphogenesis. Techniques from compiler technology are applied to generate attributes (new fields) in the database, to simplify query development for the recursively-structured branching relationship. Use of biological terminology in an interactive query builder contributes towards making the system biologist-friendly. PMID:12069728

  7. Simulated coal gas MCFC power plant systems verification. Technical progress report

    SciTech Connect

    1998-04-01

    The following tasks are included in this project: Commercialization; Power plant development; Manufacturing facilities development; Test facility development; Stack research; and Advanced research and technology development. This report briefly describes the subtasks still to be completed: Power plant system test with reformed natural gas; Upgrading of existing, US government-owned, test facilities; and Advanced MCFC component research.

  8. Some Sensitivity Studies of Chemical Transport Simulated in Models of the Soil-Plant-Litter System

    SciTech Connect

    Begovich, C.L.

    2002-10-28

    Fifteen parameters in a set of five coupled models describing carbon, water, and chemical dynamics in the soil-plant-litter system were varied in a sensitivity analysis of model response. Results are presented for chemical distribution in the components of soil, plants, and litter along with selected responses of biomass, internal chemical transport (xylem and phloem pathways), and chemical uptake. Response and sensitivity coefficients are presented for up to 102 model outputs in an appendix. Two soil properties (chemical distribution coefficient and chemical solubility) and three plant properties (leaf chemical permeability, cuticle thickness, and root chemical conductivity) had the greatest influence on chemical transport in the soil-plant-litter system under the conditions examined. Pollutant gas uptake (SO{sub 2}) increased with change in plant properties that increased plant growth. Heavy metal dynamics in litter responded to plant properties (phloem resistance, respiration characteristics) which induced changes in the chemical cycling to the litter system. Some of the SO{sub 2} and heavy metal responses were not expected but became apparent through the modeling analysis.

  9. Development of a computer-simulation model for a plant-nematode system.

    PubMed

    Ferris, H

    1976-07-01

    A computer-simulation model (MELSIM) of a Meloidogyne-grapevine system is developed. The objective is to attempt a holistic approach to the study of nematode population dynamics by using experimental data from controlled environmental conditions. A simulator with predictive ability would be useful in considering pest management alternatives and in teaching. Rates of flow and interaction between the components of the system are governed by environmental conditions. Equations for these rates are determined by fitting curves to data from controlled environment studies. Development of the model and trial simulations have revealed deficiencies in understanding of the system and identified areas where further research is necessary. PMID:19308232

  10. Development of a Computer-Simulation Model for a Plant-Nematode System

    PubMed Central

    Ferris, H.

    1976-01-01

    A computer-simulation model (MELSIM) of a Meloidogyne-grapevine system is developed. The objective is to attempt a holistic approach to the study of nematode population dynamics by using experimental data from controlled environmental conditions. A simulator with predictive ability would be useful in considering pest management alternatives and in teaching. Rates of flow and interaction between the components of the system are governed by environmental conditions. Equations for these rates are determined by fitting curves to data from controlled environment studies. Development of the model and trial simulations have revealed deficiencies in understanding of the system and identified areas where further research is necessary. PMID:19308232

  11. L-Py: An L-System Simulation Framework for Modeling Plant Architecture Development Based on a Dynamic Language

    PubMed Central

    Boudon, Frédéric; Pradal, Christophe; Cokelaer, Thomas; Prusinkiewicz, Przemyslaw; Godin, Christophe

    2012-01-01

    The study of plant development requires increasingly powerful modeling tools to help understand and simulate the growth and functioning of plants. In the last decade, the formalism of L-systems has emerged as a major paradigm for modeling plant development. Previous implementations of this formalism were made based on static languages, i.e., languages that require explicit definition of variable types before using them. These languages are often efficient but involve quite a lot of syntactic overhead, thus restricting the flexibility of use for modelers. In this work, we present an adaptation of L-systems to the Python language, a popular and powerful open-license dynamic language. We show that the use of dynamic language properties makes it possible to enhance the development of plant growth models: (i) by keeping a simple syntax while allowing for high-level programming constructs, (ii) by making code execution easy and avoiding compilation overhead, (iii) by allowing a high-level of model reusability and the building of complex modular models, and (iv) by providing powerful solutions to integrate MTG data-structures (that are a common way to represent plants at several scales) into L-systems and thus enabling to use a wide spectrum of computer tools based on MTGs developed for plant architecture. We then illustrate the use of L-Py in real applications to build complex models or to teach plant modeling in the classroom. PMID:22670147

  12. L-py: an L-system simulation framework for modeling plant architecture development based on a dynamic language.

    PubMed

    Boudon, Frédéric; Pradal, Christophe; Cokelaer, Thomas; Prusinkiewicz, Przemyslaw; Godin, Christophe

    2012-01-01

    The study of plant development requires increasingly powerful modeling tools to help understand and simulate the growth and functioning of plants. In the last decade, the formalism of L-systems has emerged as a major paradigm for modeling plant development. Previous implementations of this formalism were made based on static languages, i.e., languages that require explicit definition of variable types before using them. These languages are often efficient but involve quite a lot of syntactic overhead, thus restricting the flexibility of use for modelers. In this work, we present an adaptation of L-systems to the Python language, a popular and powerful open-license dynamic language. We show that the use of dynamic language properties makes it possible to enhance the development of plant growth models: (i) by keeping a simple syntax while allowing for high-level programming constructs, (ii) by making code execution easy and avoiding compilation overhead, (iii) by allowing a high-level of model reusability and the building of complex modular models, and (iv) by providing powerful solutions to integrate MTG data-structures (that are a common way to represent plants at several scales) into L-systems and thus enabling to use a wide spectrum of computer tools based on MTGs developed for plant architecture. We then illustrate the use of L-Py in real applications to build complex models or to teach plant modeling in the classroom. PMID:22670147

  13. Modification of a computer simulation model for a plant-nematode system.

    PubMed

    Ferris, H

    1978-04-01

    New data on egg development and death rates, and refinements of logic concerning interaction of the nematode and host, were incorporated into a simulation model of a Meloidogyne arenaria and grapevine system. Simulations of field data improved but other areas of weakness in the model were discovered. Two peaks in the egg population curve suggested that the nematode was able to complete two life cycles before host dormancy and declining temperatures limited physiological activity. PMID:19305839

  14. Modification of a Computer Simulation Model for a Plant-Nematode System

    PubMed Central

    Ferris, H.

    1978-01-01

    New data on egg development and death rates, and refinements of logic concerning interaction of the nematode and host, were incorporated into a simulation model of a Meloidogyne arenaria and grapevine system. Simulations of field data improved but other areas of weakness in the model were discovered. Two peaks in the egg population curve suggested that the nematode was able to complete two life cycles before host dormancy and declining temperatures limited physiological activity. PMID:19305839

  15. Simulation and system analysis of an ethanol fuel processor/PEM fuel cell power plant

    SciTech Connect

    Amphlett, J.C.; Leclerc, S.; Mann, R.F.; Peppley, B.A.; Roberge, P.R.

    1998-07-01

    Proton-exchange membrane (PEM) fuel cell systems offer a potential power source for utility and mobile applications. Currently, practical fuel cell systems use fuel processors for the production of a hydrogen-rich gas for the fuel cell anode. Liquid fuels such as ethanol, which can be produced from renewable feed stocks, are attractive options as feeds to a fuel processor. The generation of hydrogen gas for fuel cells, in most cases, becomes the crucial design issue with respect to weight and volume in these applications. Furthermore, these fuel processors require a gas clean-up system to ensure that the fuel quality meets the demands of the cell anode. The endothermic nature of the reformer will have a significant effect on the overall system efficiency. The gas clean-up system may also significantly affect the overall heat balance. A model of a methanol steam reformer that was previously developed has been used as the basis for a model for an ethanol steam reformer. Similarly, a steady-state electrochemical fuel cell model (SSEM) that was previously developed was used. A palladium diffuser purifier simulation was used for gas clean-up. The ethanol fuel processor model and the SSEM have been incorporated into a process simulation and system analysis of an ethanol-fueled reformer/fuel cell system. The performance of this complete system has been investigated for a variety of operating conditions. Assuming that ethanol reforming could be done at 400 C, a net electrical efficiency based on the LHV of ethanol of approximately 54% was calculated. The efficiency, however, is very sensitive to reforming temperature and drops rapidly as the reformer temperature increases. The fractional recovery of hydrogen by the gas clean-up system is also an important factor. The net thermal efficiency passes through a maximum at the point when the heating value in the retentate from the purifier just meets the endothermic heating requirements of the reformer.

  16. Nuclear Power Plant Simulation Game.

    ERIC Educational Resources Information Center

    Weiss, Fran

    1979-01-01

    Presents a nuclear power plant simulation game which is designed to involve a class of 30 junior or senior high school students. Scientific, ecological, and social issues covered in the game are also presented. (HM)

  17. Geographical information systems and air pollution simulation for Megalopolis' electric power plant in Peloponnese, Greece.

    PubMed

    Theophanides, Mike; Anastassopoulou, Jane; Theophanides, Theophile

    2014-01-01

    The growth and sophistication of geographic information systems (GIS) have propelled us into a new era of environmental analyses. Air pollution is a growing concern in populated areas as many recent studies have associated high levels of pollution with increased illnesses and mortality. The study will focus on the toxicity levels incurred by radioactive lignite-burning Power Generation facilities located in Megalopolis, Greece. An estimate of pollution emissions followed by dispersion simulations for various atmospheric conditions will be given. The exercise will be integrated with a Geographical Information System (GIS) for defining the emission sources and visualizing the dispersion of pollutants over the geographical terrain. Data samples were collected from vegetation in the surrounding areas and analyzed for radioactivity. High energy levels (up to 4-5 times higher than recommended standards, (UNCEAR, 1982) were found in several samples containing (226)Ra, (232)Th, (234)Th, (40)K and (238)U. The study concludes that air quality and vegetation of the neighbouring areas is adversely affected by industrial waste. Greater pollution controls and air quality monitoring should be applied for the benefit and health of its citizens. Radioactivity in food and water and inhaled air become very dangerous for public health thus, the levels of radioactivity should be kept within UNCEAR 1982 limits. PMID:24798903

  18. Dynamic simulator for PEFC propulsion plant

    SciTech Connect

    Hiraide, Masataka; Kaneda, Eiichi; Sato, Takao

    1996-12-31

    This report covers part of a joint study on a PEFC propulsion system for surface ships, summarized in a presentation to this Seminar, entitled {open_quote}Study on a Polymer Electrolyte Fuel Cell (PEFC) Propulsion System for Surface Ships{close_quotes}, and which envisages application to a 1,500 DWT cargo vessel. The work presented here focuses on a simulation study on PEFC propulsion plant performance, and particularly on the system response to changes in load. Using a dynamic simulator composed of system components including fuel cell, various simulations were executed, to examine the performance of the system as a whole and of the individual system components under quick and large load changes such as occasioned by maneuvering operations and by racing when the propeller emerges above water in heavy sea.

  19. Plant Phenotype Characterization System

    SciTech Connect

    Daniel W McDonald; Ronald B Michaels

    2005-09-09

    This report is the final scientific report for the DOE Inventions and Innovations Project: Plant Phenotype Characterization System, DE-FG36-04GO14334. The period of performance was September 30, 2004 through July 15, 2005. The project objective is to demonstrate the viability of a new scientific instrument concept for the study of plant root systems. The root systems of plants are thought to be important in plant yield and thus important to DOE goals in renewable energy sources. The scientific study and understanding of plant root systems is hampered by the difficulty in observing root activity and the inadequacy of existing root study instrumentation options. We have demonstrated a high throughput, non-invasive, high resolution technique for visualizing plant root systems in-situ. Our approach is based upon low-energy x-ray radiography and the use of containers and substrates (artificial soil) which are virtually transparent to x-rays. The system allows us to germinate and grow plant specimens in our containers and substrates and to generate x-ray images of the developing root system over time. The same plant can be imaged at different times in its development. The system can be used for root studies in plant physiology, plant morphology, plant breeding, plant functional genomics and plant genotype screening.

  20. Impact of herbivore-induced plant volatiles on parasitoid foraging success: a spatial simulation of the Cotesia rubecula, Pieris rapae, and Brassica oleracea system.

    PubMed

    Puente, Molly; Magori, Krisztian; Kennedy, George G; Gould, Fred

    2008-07-01

    Many parasitoids are known to use herbivore-induced plant volatiles as cues to locate hosts. However, data are lacking on how much of an advantage a parasitoid can gain from following these plant cues and which factors can limit the value of these cues to the parasitoid. In this study, we simulate the Cotesia rubecula-Pieris rapae-Brassica oleracea system, and ask how many more hosts can a parasitoid attack in a single day of foraging by following plant signals versus randomly foraging. We vary herbivore density, plant response time, parasitoid flight distance, and available host stages to see under which conditions parasitoids benefit from herbivore-induced plant cues. In most of the parameter combinations studied, parasitoids that responded to cues attacked more hosts than those that foraged randomly. Parasitoids following plant cues attacked up to ten times more hosts when they were able to successfully attack herbivores older than first instar; however, if parasitoids were limited to first instar hosts, those following plant cues were at a disadvantage when plants took longer than a day to respond to herbivory. At low herbivore densities, only parasitoids with a larger foraging radius could take advantage of plant cues. Although preference for herbivore-induced volatiles was not always beneficial for a parasitoid, under the most likely natural conditions, the model predicts that C. rubecula gains fitness from following plant cues. PMID:18438615

  1. Growth of plant tissue cultures in simulated lunar soil: Implications for a lunar base Controlled Ecological Life Support System (CELSS)

    NASA Technical Reports Server (NTRS)

    Venketeswaran, S.

    1987-01-01

    Experiments to determine whether plant tissue cultures can be grown in the presence of simulated lunar soil (SLS) and the effect of simulated lunar soil on the growth and morphogenesis of such cultures, as well as the effect upon the germination of seeds and the development of seedlings were carried out . Preliminary results on seed germination and seedling growth of rice and calli growth of winged bean and soybean indicate that there is no toxicity or inhibition caused by SLS. SLS can be used as a support medium with supplements of certain major and micro elements.

  2. Power Plant Systems Analysis

    NASA Technical Reports Server (NTRS)

    Williams, J. R.; Yang, Y. Y.

    1973-01-01

    Three basic thermodynamic cycles of advanced nuclear MHD power plant systems are studied. The effect of reactor exit temperature and space radiator temperature on the overall thermal efficiency of a regenerative turbine compressor power plant system is shown. The effect of MHD pressure ratio on plant efficiency is also described, along with the dependence of MHD power output, compressor power requirement, turbine power output, mass flow rate of H2, and overall plant efficiency on the reactor exit temperature for a specific configuration.

  3. Plant Systems Biology (editorial)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In June 2003, Plant Physiology published an Arabidopsis special issue devoted to plant systems biology. The intention of Natasha Raikhel and Gloria Coruzzi, the two editors of this first-of-its-kind issue, was ‘‘to help nucleate this new effort within the plant community’’ as they considered that ‘‘...

  4. Growth of plant tissue cultures in simulated lunar soil: Implications for a lunar base CELSS (Controlled Ecological Life Support System)

    NASA Technical Reports Server (NTRS)

    Venketeswaran, S.

    1988-01-01

    Experiments were carried out on plant tissue cultures, seed germination, seedling development and plants grown on Simulated Lunar Soil to evaluate the potential of future development of lunar based agriculture. The studies done to determine the effect of the placement of SLS on tissue cultures showed no adverse effect of SLS on tissue cultures. Although statistically insignificant, SLS in suspension showed a comparatively higher growth rate. Observations indicate the SLS, itself cannot support calli growth but was able to show a positive effect on growth rate of calli when supplemented with MS salts. This positive effect related to nutritive value of the SLS was found to have improved at high pH levels, than at the recommended low pH levels for standard media. Results from seed germination indicated that there is neither inhibitory, toxicity nor stimulatory effect of SLS, even though SLS contains high amounts of aluminum compounds compared to earth soil. Analysis of seeding development and growth data showed significant reduction in growth rate indicating that, SLS was a poor growth medium for plant life. This was confirmed by the studies done with embryos and direct plant growth on SLS. Further observations attributed this poor quality of SLS is due to it's lack of essential mineral elements needed for plant growth. By changing the pH of the soil, to more basic conditions, the quality of SLS for plant growth could be improved up to a significant level. Also it was found that the quality of SLS could be improved by almost twice, by external supply of major mineral elements, directly to SLS.

  5. Distribution system simulator

    NASA Technical Reports Server (NTRS)

    Bahrami, K. A.; Kirkham, H.; Rahman, S.

    1986-01-01

    In a series of tests performed under the Department of Energy auspices, power line carrier propagation was observed to be anomalous under certain circumstances. To investigate the cause, a distribution system simulator was constructed. The simulator was a physical simulator that accurately represented the distribution system from below power frequency to above 50 kHz. Effects such as phase-to-phase coupling and skin effect were modeled. Construction details of the simulator, and experimental results from its use are presented.

  6. Threat radar system simulations

    NASA Astrophysics Data System (ADS)

    Miller, L.

    The capabilities, requirements, and goals of radar emitter simulators are discussed. Simulators are used to evaluate competing receiver designs, to quantify the performance envelope of a radar system, and to model the characteristics of a transmitted signal waveform. A database of candidate threat systems is developed and, in concert with intelligence data on a given weapons system, permits upgrading simulators to new projected threat capabilities. Four currently available simulation techniques are summarized, noting the usefulness of developing modular software for fast controlled-cost upgrades of simulation capabilities.

  7. Designing Simulation Systems

    ERIC Educational Resources Information Center

    Twelker, Paul A.

    1969-01-01

    "The purpose of this paper is to outline the approach to designing instructional simulation systems developed at Teaching Research. The 13 phases of simulation design will be summarized, and an effort will be made to expose the vital decision points that confront the designer as he develops simulation experiences. (Author)

  8. Dynamic simulation of chemical industry wastewater treatment plants.

    PubMed

    Bury, S J; Groot, C K; Huth, C; Hardt, N

    2002-01-01

    High variability, stringent effluent permits, and often extreme operating conditions define the practice of wastewater treatment in the chemical industry. This paper reviews the benefits and challenges of applying dynamic simulation to chemical-industry wastewater treatment plants by describing case studies at full-scale wastewater treatment plants (WWTP). The applications range from process troubleshooting to optimization and control. The applications have been valuable and useful in developing a deeper understanding of the plants as integrated systems. However there still remains substantial work to implement the dynamic simulations for daily real-time use by plant engineers and operators. This opportunity to improve plant operations is still largely untapped and will remain so until dynamic state estimation and data reconciliation are incorporated into simulation packages for use in developing the on-line simulations. PMID:11936653

  9. Instrumented Architectural Simulation System

    NASA Technical Reports Server (NTRS)

    Delagi, B. A.; Saraiya, N.; Nishimura, S.; Byrd, G.

    1987-01-01

    Simulation of systems at an architectural level can offer an effective way to study critical design choices if (1) the performance of the simulator is adequate to examine designs executing significant code bodies, not just toy problems or small application fragements, (2) the details of the simulation include the critical details of the design, (3) the view of the design presented by the simulator instrumentation leads to useful insights on the problems with the design, and (4) there is enough flexibility in the simulation system so that the asking of unplanned questions is not suppressed by the weight of the mechanics involved in making changes either in the design or its measurement. A simulation system with these goals is described together with the approach to its implementation. Its application to the study of a particular class of multiprocessor hardware system architectures is illustrated.

  10. Nuclear Plant Analyzer: an interactive TRAC/RELAP Power-Plant Simulation Program

    SciTech Connect

    Steinke, R.; Booker, C.; Giguere, P.; Liles, D.; Mahaffy, J.; Turner, M.; Wiley, R.

    1984-01-01

    The Nuclear Plant Analyzer (NPA) is a computer-software interface for executing the TRAC or RELAP5 power-plant systems codes. The NPA is designed to use advanced supercomputers, long-distance data communications, and a remote workstation terminal with interactive computer graphics to analyze power-plant thermal-hydraulic behavior. The NPA interface simplifies the running of these codes through automated procedures and dialog interaction. User understanding of simulated-plant behavior is enhanced through graphics displays of calculational results. These results are displayed concurrently with the calculation. The user has the capability to override the plant's modeled control system with hardware adjustment commands. This gives the NPA the utility of a simulator, and at the same time, the accuracy of an advanced, best-estimate, power-plant systems code for plant operation and safety analysis.

  11. Los Alamos Nuclear Plant Analyzer: an interactive power-plant simulation program

    SciTech Connect

    Steinke, R.; Booker, C.; Giguere, P.; Liles, D.R.; Mahaffy, J.H.; Turner, M.R.

    1984-01-01

    The Nuclear Plant Analyzer (NPA) is a computer-software interface for executing the TRAC or RELAP5 power-plant systems codes. The NPA is designed to use advanced supercomputers, long-distance data communications, and a remote workstation terminal with interactive computer graphics to analyze power-plant thermal-hydraulic behavior. The NPA interface simplifies the running of these codes through automated procedures and dialog interaction. User understanding of simulated-plant behavior is enhanced through graphics displays of calculational results. These results are displayed concurrently with the calculation. The user has the capability to override the plant's modeled control system with hardware-adjustment commands. This gives the NPA the utility of a simulator, and at the same time, the accuracy of an advanced, best-estimate, power-plant systems code for plant operation and safety analysis.

  12. Spiral Growth in Plants: Models and Simulations

    ERIC Educational Resources Information Center

    Allen, Bradford D.

    2004-01-01

    The analysis and simulation of spiral growth in plants integrates algebra and trigonometry in a botanical setting. When the ideas presented here are used in a mathematics classroom/computer lab, students can better understand how basic assumptions about plant growth lead to the golden ratio and how the use of circular functions leads to accurate…

  13. Numeric Simulation of Plant Signaling Networks1

    PubMed Central

    Genoud, Thierry; Trevino Santa Cruz, Marcela B.; Métraux, Jean-Pierre

    2001-01-01

    Plants have evolved an intricate signaling apparatus that integrates relevant information and allows an optimal response to environmental conditions. For instance, the coordination of defense responses against pathogens involves sophisticated molecular detection and communication systems. Multiple protection strategies may be deployed differentially by the plant according to the nature of the invading organism. These responses are also influenced by the environment, metabolism, and developmental stage of the plant. Though the cellular signaling processes traditionally have been described as linear sequences of events, it is now evident that they may be represented more accurately as network-like structures. The emerging paradigm can be represented readily with the use of Boolean language. This digital (numeric) formalism allows an accurate qualitative description of the signal transduction processes, and a dynamic representation through computer simulation. Moreover, it provides the required power to process the increasing amount of information emerging from the fields of genomics and proteomics, and from the use of new technologies such as microarray analysis. In this review, we have used the Boolean language to represent and analyze part of the signaling network of disease resistance in Arabidopsis. PMID:11500542

  14. Numeric simulation of plant signaling networks.

    PubMed

    Genoud, T; Trevino Santa Cruz, M B; Métraux, J P

    2001-08-01

    Plants have evolved an intricate signaling apparatus that integrates relevant information and allows an optimal response to environmental conditions. For instance, the coordination of defense responses against pathogens involves sophisticated molecular detection and communication systems. Multiple protection strategies may be deployed differentially by the plant according to the nature of the invading organism. These responses are also influenced by the environment, metabolism, and developmental stage of the plant. Though the cellular signaling processes traditionally have been described as linear sequences of events, it is now evident that they may be represented more accurately as network-like structures. The emerging paradigm can be represented readily with the use of Boolean language. This digital (numeric) formalism allows an accurate qualitative description of the signal transduction processes, and a dynamic representation through computer simulation. Moreover, it provides the required power to process the increasing amount of information emerging from the fields of genomics and proteomics, and from the use of new technologies such as microarray analysis. In this review, we have used the Boolean language to represent and analyze part of the signaling network of disease resistance in Arabidopsis. PMID:11500542

  15. Observing System Simulation Experiments

    NASA Technical Reports Server (NTRS)

    Prive, Nikki

    2015-01-01

    This presentation gives an overview of Observing System Simulation Experiments (OSSEs). The components of an OSSE are described, along with discussion of the process for validating, calibrating, and performing experiments. a.

  16. Simulation study supporting wastewater treatment plant upgrading.

    PubMed

    Hvala, N; Vrecko, D; Burica, O; Strazar, M; Levstek, M

    2002-01-01

    The paper presents a study where upgrading of an existing wastewater treatment plant was supported by simulation. The aim of the work was to decide between two technologies to improve nitrogen removal: a conventional activated sludge process (ASP) and a moving bed biofilm reactor (MBBR). To perform simulations, the mathematical models of both processes were designed. The models were calibrated based on data from ASP and MBBR pilot plants operating in parallel on the existing plant. Only two kinetic parameters needed to be adjusted to represent the real plant behaviour. Steady-state analyses have shown a similar efficiency of both processes in relation to carbon removal, but improved performance of MBBR in relation to nitrogen removal. Better performance of MBBR can be expected especially at low temperatures. Simulations have not confirmed the expected less volume required for the MBBR process. Finally, the MBBR was chosen for plant upgrading. The developed process model will be further used to evaluate the final plant configuration and to optimise the plant operating parameters. PMID:12361028

  17. Estimating solar radiation for plant simulation models

    NASA Technical Reports Server (NTRS)

    Hodges, T.; French, V.; Leduc, S.

    1985-01-01

    Five algorithms producing daily solar radiation surrogates using daily temperatures and rainfall were evaluated using measured solar radiation data for seven U.S. locations. The algorithms were compared both in terms of accuracy of daily solar radiation estimates and terms of response when used in a plant growth simulation model (CERES-wheat). Requirements for accuracy of solar radiation for plant growth simulation models are discussed. One algorithm is recommended as being best suited for use in these models when neither measured nor satellite estimated solar radiation values are available.

  18. Numerical Propulsion System Simulation

    NASA Technical Reports Server (NTRS)

    Naiman, Cynthia

    2006-01-01

    The NASA Glenn Research Center, in partnership with the aerospace industry, other government agencies, and academia, is leading the effort to develop an advanced multidisciplinary analysis environment for aerospace propulsion systems called the Numerical Propulsion System Simulation (NPSS). NPSS is a framework for performing analysis of complex systems. The initial development of NPSS focused on the analysis and design of airbreathing aircraft engines, but the resulting NPSS framework may be applied to any system, for example: aerospace, rockets, hypersonics, power and propulsion, fuel cells, ground based power, and even human system modeling. NPSS provides increased flexibility for the user, which reduces the total development time and cost. It is currently being extended to support the NASA Aeronautics Research Mission Directorate Fundamental Aeronautics Program and the Advanced Virtual Engine Test Cell (AVETeC). NPSS focuses on the integration of multiple disciplines such as aerodynamics, structure, and heat transfer with numerical zooming on component codes. Zooming is the coupling of analyses at various levels of detail. NPSS development includes capabilities to facilitate collaborative engineering. The NPSS will provide improved tools to develop custom components and to use capability for zooming to higher fidelity codes, coupling to multidiscipline codes, transmitting secure data, and distributing simulations across different platforms. These powerful capabilities extend NPSS from a zero-dimensional simulation tool to a multi-fidelity, multidiscipline system-level simulation tool for the full development life cycle.

  19. Software simulator for multiple computer simulation system

    NASA Technical Reports Server (NTRS)

    Ogrady, E. P.

    1983-01-01

    A description is given of the structure and use of a computer program that simulates the operation of a parallel processor simulation system. The program is part of an investigation to determine algorithms that are suitable for simulating continous systems on a parallel processor configuration. The simulator is designed to accurately simulate the problem-solving phase of a simulation study. Care has been taken to ensure the integrity and correctness of data exchanges and to correctly sequence periods of computation and periods of data exchange. It is pointed out that the functions performed during a problem-setup phase or a reset phase are not simulated. In particular, there is no attempt to simulate the downloading process that loads object code into the local, transfer, and mapping memories of processing elements or the memories of the run control processor and the system control processor. The main program of the simulator carries out some problem-setup functions of the system control processor in that it requests the user to enter values for simulation system parameters and problem parameters. The method by which these values are transferred to the other processors, however, is not simulated.

  20. Virtual Simulation of Vision 21 Energy Plants

    SciTech Connect

    Syamlal, Madhava; Felix, Paul E.; Osawe, Maxwell O.; Fiveland, Woodrow A.; Sloan, David G.; Zitney, Stephen E.; Joop, Frank; Cleetus, Joseph; Lapshin, Igor B.

    2001-11-06

    The Vision 21 Energy plants will be designed by combining several individual power, chemical, and fuel-conversion technologies. These independently developed technologies or technology modules can be interchanged and combined to form the complete Vision 21 plant that achieves the needed level of efficiency and environmental performance at affordable costs. The knowledge about each technology module must be captured in computer models so that the models can be linked together to simulate the entire Vision 21 power plant in a Virtual Simulation environment. Eventually the Virtual Simulation will find application in conceptual design, final design, plant operation and control, and operator training. In this project we take the first step towards developing such a Vision 21 Simulator. There are two main knowledge domains of a plant--the process domain (what is in the pipes), and the physical domain (the pipes and equipment that make up the plant). Over the past few decades, commercial software tools have been developed for each of these functions. However, there are three main problems that inhibit the design and operation of power plants: (1) Many of these tools, largely developed for chemicals and refining, have not been widely adopted in the power industry. (2) Tools are not integrated across functions. For example, the knowledge represented by computational fluid dynamics (CFD) models of equipment is not used in process-level simulations. (3) No tool exists for readily integrating the design and behavioral knowledge about components. These problems must be overcome to develop the Vision 21 Simulator. In this project our major objective is to achieve a seamless integration of equipment-level and process-level models and apply the integrated software to power plant simulations. Specifically we are developing user-friendly tools for linking process models (Aspen Plus) with detailed equipment models (FLUENT CFD and other proprietary models). Such integration will

  1. Data Systems Dynamic Simulator

    NASA Technical Reports Server (NTRS)

    Rouff, Christopher; Clark, Melana; Davenport, Bill; Message, Philip

    1993-01-01

    The Data System Dynamic Simulator (DSDS) is a discrete event simulation tool. It was developed for NASA for the specific purpose of evaluating candidate architectures for data systems of the Space Station era. DSDS provides three methods for meeting this requirement. First, the user has access to a library of standard pre-programmed elements. These elements represent tailorable components of NASA data systems and can be connected in any logical manner. Secondly, DSDS supports the development of additional elements. This allows the more sophisticated DSDS user the option of extending the standard element set. Thirdly, DSDS supports the use of data streams simulation. Data streams is the name given to a technique that ignores packet boundaries, but is sensitive to rate changes. Because rate changes are rare compared to packet arrivals in a typical NASA data system, data stream simulations require a fraction of the CPU run time. Additionally, the data stream technique is considerably more accurate than another commonly-used optimization technique.

  2. Simulated coal-gas fueled carbonate fuel cell power plant system verification. Final report, September 1990--June 1995

    SciTech Connect

    1995-03-01

    This report summarizes work performed under U.S. Department of Energy, Morgantown Energy Technology Center (DOE/METC) Contract DE-AC-90MC27168 for September 1990 through March 1995. Energy Research Corporation (ERC), with support from DOE, EPRI, and utilities, has been developing a carbonate fuel cell technology. ERC`s design is a unique direct fuel cell (DFC) which does not need an external fuel reformer. An alliance was formed with a representative group of utilities and, with their input, a commercial entry product was chosen. The first 2 MW demonstration unit was planned and construction begun at Santa Clara, CA. A conceptual design of a 10OMW-Class dual fuel power plant was developed; economics of natural gas versus coal gas use were analyzed. A facility was set up to manufacture 2 MW/yr of carbonate fuel cell stacks. A 100kW-Class subscale power plant was built and several stacks were tested. This power plant has achieved an efficiency of {approximately}50% (LHV) from pipeline natural gas to direct current electricity conversion. Over 6,000 hours of operation including 5,000 cumulative hours of stack operation were demonstrated. One stack was operated on natural gas at 130 kW, which is the highest carbonate fuel cell power produced to date, at 74% fuel utilization, with excellent performance distribution across the stack. In parallel, carbonate fuel cell performance has been improved, component materials have been proven stable with lifetimes projected to 40,000 hours. Matrix strength, electrolyte distribution, and cell decay rate have been improved. Major progress has been achieved in lowering stack cost.

  3. Recovery of mineral salts and potable water from desalting plant effluents by evaporation. Part II. Proposed simulation system for salt recovery

    SciTech Connect

    Abdel-Aal, H.K.; Ba-Lubaid, K.M.; Shaikh, A.A.; Al-Harbi, D.K. )

    1990-04-01

    Salt recovery from rejected brines of the Al-Khobar Water Desalination Plant, Saudi Arabia, is studied through the simulation of a modified MSF system. Two phases of concentrations are planned: Phase I will concentrate the main effluent from 6.4 wt% total salt to 28.8%, while Phase II will use the effluents from Phase I as a feed to undergo further evaporation and cooling. NaCl and water are produced throughout this phase, while the end residue product will be essentially MgCl{sub 2}, since it is the most soluble. A mathematical model is developed and used to perform stage-to-stage material and heat balance calculations. Concentrations of NaCl and MgCl{sub 2} in the streams entering and leaving a stage are determined by using the solubility correlation developed in Part I. Simulation results show that by using 5,210 tons/h brine as a feed for Phase I, they can recover 4,430 tons/h fresh water, 277 tons/h NaCl, and 502 tons/h bittern (in which the ratio of MgCl{sub 2}/NaCl is increased to 12) as the very final products of the integrated scheme. This bittern provides 30 tons/h MgCl{sub 2} as an end product.

  4. Parallel system simulation

    SciTech Connect

    Tai, H.M.; Saeks, R.

    1984-03-01

    A relaxation algorithm for solving large-scale system simulation problems in parallel is proposed. The algorithm, which is composed of both a time-step parallel algorithm and a component-wise parallel algorithm, is described. The interconnected nature of the system, which is characterized by the component connection model, is fully exploited by this approach. A technique for finding an optimal number of the time steps is also described. Finally, this algorithm is illustrated via several examples in which the possible trade-offs between the speed-up ratio, efficiency, and waiting time are analyzed.

  5. Simulation model for the closed plant experiment facility of CEEF.

    PubMed

    Abe, Koichi; Ishikawa, Yoshio; Kibe, Seishiro; Nitta, Keiji

    2005-01-01

    The Closed Ecology Experiment Facilities (CEEF) is a testbed for Controlled Ecological Life Support Systems (CELSS) investigations. CEEF including the physico-chemical material regenerative system has been constructed for the experiments of material circulation among plants, breeding animals and crew of CEEF. Because CEEF is a complex system, an appropriate schedule for the operation must be prepared in advance. The CEEF behavioral Prediction System, CPS, that will help to confirm the operation schedule, is under development. CPS will simulate CEEFs behavior with data (conditions of equipments, quantity of materials in tanks, etc.) of CEEF and an operation schedule that will be made by the operation team everyday, before the schedule will be carried out. The result of the simulation will show whether the operation schedule is appropriate or not. In order to realize CPS, models of the simulation program that is installed in CPS must mirror the real facilities of CEEF. For the first step of development, a flexible algorithm of the simulation program was investigated. The next step was development of a replicate simulation model of the material circulation system for the Closed Plant Experiment Facility (CPEF) that is a part of CEEF. All the parts of a real material circulation system for CPEF are connected together and work as a complex mechanism. In the simulation model, the system was separated into 38 units according to its operational segmentation. In order to develop each model for its corresponding unit, specifications for the model were fixed based on the specifications of the real part. These models were put into a simulation model for the system. PMID:16175692

  6. Simulation model for the closed plant experiment facility of CEEF

    NASA Astrophysics Data System (ADS)

    Abe, Koichi; Ishikawa, Yoshio; Kibe, Seishiro; Nitta, Keiji

    The Closed Ecology Experiment Facilities (CEEF) is a testbed for Controlled Ecological Life Support Systems (CELSS) investigations. CEEF including the physico-chemical material regenerative system has been constructed for the experiments of material circulation among plants, breeding animals and crew of CEEF. Because CEEF is a complex system, an appropriate schedule for the operation must be prepared in advance. The CEEF behavioral Prediction System, CPS, that will help to confirm the operation schedule, is under development. CPS will simulate CEEFs behavior with data (conditions of equipments, quantity of materials in tanks, etc.) of CEEF and an operation schedule that will be made by the operation team everyday, before the schedule will be carried out. The result of the simulation will show whether the operation schedule is appropriate or not. In order to realize CPS, models of the simulation program that is installed in CPS must mirror the real facilities of CEEF. For the first step of development, a flexible algorithm of the simulation program was investigated. The next step was development of a replicate simulation model of the material circulation system for the Closed Plant Experiment Facility (CPEF) that is a part of CEEF. All the parts of a real material circulation system for CPEF are connected together and work as a complex mechanism. In the simulation model, the system was separated into 38 units according to its operational segmentation. In order to develop each model for its corresponding unit, specifications for the model were fixed based on the specifications of the real part. These models were put into a simulation model for the system.

  7. A numerical method for power plant simulations

    SciTech Connect

    Carcasci, C.; Facchini, B.

    1996-03-01

    This paper describes a highly flexible computerized method of calculating operating data in a power cycle. The computerized method presented here permits the study of steam, gas and combined plants. Its flexibility is not restricted by any defined cycle scheme. A power plant consists of simple elements (turbine, compressor, combustor chamber, pump, etc.). Each power plant component is represented by its typical equations relating to fundamental mechanical and thermodynamic laws, so a power plant system is represented by algebraic equations, which are the typical equations of components, continuity equations, and data concerning plant conditions. This equation system is not linear, but can be reduced to a linear equation system with variable coefficients. The solution is simultaneous for each component and it is determined by an iterative process. An example of a simple gas turbine cycle demonstrates the applied technique. This paper also presents the user interface based on MS-Windows. The input data, the results, and any characteristic parameters of a complex cycle scheme are also shown.

  8. Simulation model for the Closed Plant Experimental Facilities of CEEF

    NASA Astrophysics Data System (ADS)

    Abe, K.; Ishikawa, Y.; Kibe, S.; Nitta, K.

    The Closed Ecology Experiment Facilities (CEEF) is a testbed for CELSS investigations. CEEF including the physico-chemical material regenerative system has been constructed for the experiments of material circulation among plants, breeding animals, humans (crew of the CEEF). Because CEEF is a complex system, an appropriate schedule for the operation must be prepared in advance. The CEEF behavioral Prediction System, CPS, that will help to confirm the operation schedule, is under development. CPS will simulate CEEF's behavior with data (conditions of equipments, quantity of materials in tanks, etc.) of CEEF and an operation schedule that will be made by the operation team everyday, before the schedule will be carried out. The result of the simulation will show whether the operation schedule is appropriate or not. In order to realize CPS, models of the simulation program that is installed in CPS must mirror the real facilities of CEEF. A flexible algorithm for the first step of development of the simulation program was already investigated. The next step was development of a replicate simulation model of the material circulation system for the Closed Plant Experimental Facilities (CPEF) that is a part of CEEF. All the parts of real material circulation system for CPEF are connected together and work as a complex mechanism. In the simulation model, the system was separated into 38 units according to its operational segmentation. In order to develop each model for its corresponding unit, specifications for the model were fixed based on the specifications of the real part. These models were put into a simulation model for the system.

  9. Characterization of Minnesota lunar simulant for plant growth

    NASA Technical Reports Server (NTRS)

    Oglesby, James P.; Lindsay, Willard L.; Sadeh, Willy Z.

    1993-01-01

    Processing of lunar regolith into a plant growth medium is crucial in the development of a regenerative life support system for a lunar base. Plants, which are the core of such a system, produce food and oxygen for humans and, at the same time, consume carbon dioxide. Because of the scarcity of lunar regolith, simulants must be used to infer its properties and to develop procedures for weathering and chemical analyses. The Minnesota Lunar Simulant (MLS) has been identified to date as the best available simulant for lunar regolith. Results of the dissolution studies reveal that appropriately fertilized MLS can be a suitable medium for plant growth. The techniques used in conducting these studies can be extended to investigate the suitability of actual lunar regolith as a plant growth medium. Dissolution experiments were conducted using the MLS to determine its nutritional and toxicity characteristics for plant growth and to develop weathering and chemical analysis techniques. Two weathering regimes, one with water and one with dilute organic acids simulating the root rhizosphere microenvironment, were investigated. Elemental concentrations were measured using inductively-coupled-plasma (ICP) emission spectrometry and ion chromatography (IC). The geochemical speciation model, MINTEQA2, was used to determine the major solution species and the minerals controlling them. Acidification was found to be a useful method for increasing cation concentrations to meaningful levels. Initial results indicate that MLS weathers to give neutral to slightly basic solutions which contain acceptable amounts of the essential elements required for plant nutrition (i.e., potassium, calcium, magnesium, sulfur, zinc, sodium, silicon, manganese, copper, chlorine, boron, molybdenum, and cobalt). Elements that need to be supplemented include carbon, nitrogen, and perhaps phosphorus and iron. Trace metals in solution were present at nontoxic levels.

  10. A Study on Structured Simulation Framework for Design and Evaluation of Human-Machine Interface System -Application for On-line Risk Monitoring for PWR Nuclear Power Plant-

    SciTech Connect

    Zhan, J.; Yang, M.; Li, S.C.; Peng, M.J.; Yan, S.Y.; Zhang, Z.J.

    2006-07-01

    The operators in the main control room of Nuclear Power Plant (NPP) need to monitor plant condition through operation panels and understand the system problems by their experiences and skills. It is a very hard work because even a single fault will cause a large number of plant parameters abnormal and operators are required to perform trouble-shooting actions in a short time interval. It will bring potential risks if operators misunderstand the system problems or make a commission error to manipulate an irrelevant switch with their current operation. This study aims at developing an on-line risk monitoring technique based on Multilevel Flow Models (MFM) for monitoring and predicting potential risks in current plant condition by calculating plant reliability. The proposed technique can be also used for navigating operators by estimating the influence of their operations on plant condition before they take an action that will be necessary in plant operation, and therefore, can reduce human errors. This paper describes the risk monitoring technique and illustrates its application by a Steam Generator Tube Rupture (SGTR) accident in a 2-loop Pressurized Water Reactor (PWR) Marine Nuclear Power Plant (MNPP). (authors)

  11. Gas Centrifuge Enrichment Plant Safeguards System Modeling

    SciTech Connect

    Elayat, H A; O'Connell, W J; Boyer, B D

    2006-06-05

    The U.S. Department of Energy (DOE) is interested in developing tools and methods for potential U.S. use in designing and evaluating safeguards systems used in enrichment facilities. This research focuses on analyzing the effectiveness of the safeguards in protecting against the range of safeguards concerns for enrichment plants, including diversion of attractive material and unauthorized modes of use. We developed an Extend simulation model for a generic medium-sized centrifuge enrichment plant. We modeled the material flow in normal operation, plant operational upset modes, and selected diversion scenarios, for selected safeguards systems. Simulation modeling is used to analyze both authorized and unauthorized use of a plant and the flow of safeguards information. Simulation tracks the movement of materials and isotopes, identifies the signatures of unauthorized use, tracks the flow and compilation of safeguards data, and evaluates the effectiveness of the safeguards system in detecting misuse signatures. The simulation model developed could be of use to the International Atomic Energy Agency IAEA, enabling the IAEA to observe and draw conclusions that uranium enrichment facilities are being used only within authorized limits for peaceful uses of nuclear energy. It will evaluate improved approaches to nonproliferation concerns, facilitating deployment of enhanced and cost-effective safeguards systems for an important part of the nuclear power fuel cycle.

  12. Coupling expert systems and simulation

    NASA Technical Reports Server (NTRS)

    Kawamura, K.; Beale, G.; Padalkar, S.; Rodriguez-Moscoso, J.; Hsieh, B. J.; Vinz, F.; Fernandez, K. R.

    1988-01-01

    A prototype coupled system called NESS (NASA Expert Simulation System) is described. NESS assists the user in running digital simulations of dynamic systems, interprets the output data to performance specifications, and recommends a suitable series compensator to be added to the simulation model.

  13. A COMPUTATIONAL WORKBENCH ENVIRONMENT FOR VIRTUAL POWER PLANT SIMULATION

    SciTech Connect

    Mike Bockelie; Dave Swensen; Martin Denison; Adel Sarofim; Connie Senior

    2004-12-22

    In this report is described the work effort to develop and demonstrate a software framework to support advanced process simulations to evaluate the performance of advanced power systems. Integrated into the framework are a broad range of models, analysis tools, and visualization methods that can be used for the plant evaluation. The framework provides a tightly integrated problem-solving environment, with plug-and-play functionality, and includes a hierarchy of models, ranging from fast running process models to detailed reacting CFD models. The framework places no inherent limitations on the type of physics that can be modeled, numerical techniques, or programming languages used to implement the equipment models, or the type or amount of data that can be exchanged between models. Tools are provided to analyze simulation results at multiple levels of detail, ranging from simple tabular outputs to advanced solution visualization methods. All models and tools communicate in a seamless manner. The framework can be coupled to other software frameworks that provide different modeling capabilities. Three software frameworks were developed during the course of the project. The first framework focused on simulating the performance of the DOE Low Emissions Boiler System Proof of Concept facility, an advanced pulverized-coal combustion-based power plant. The second framework targeted simulating the performance of an Integrated coal Gasification Combined Cycle - Fuel Cell Turbine (IGCC-FCT) plant configuration. The coal gasifier models included both CFD and process models for the commercially dominant systems. Interfacing models to the framework was performed using VES-Open, and tests were performed to demonstrate interfacing CAPE-Open compliant models to the framework. The IGCC-FCT framework was subsequently extended to support Virtual Engineering concepts in which plant configurations can be constructed and interrogated in a three-dimensional, user-centered, interactive

  14. Transportation Anslysis Simulation System

    SciTech Connect

    2004-08-23

    TRANSIMS version 3.1 is an integrated set of analytical and simulation models and supporting databases. The system is designed to create a virtual metropolitan region with representation of each of the region’s individuals, their activities and the transportation infrastructure they use. TRANSIMS puts into practice a new, disaggregate approach to travel demand modeling using agent-based micro-simulation technology. TRANSIMS methodology creates a virtual metropolitan region with representation of the transportation infrastructure and the population, at the level of households and individual travelers. Trips a planned to satisfy the population’s activity pattems at the individual traveler level. TRANSIMS then simulates the movement of travelers and vehicles across the transportation network using multiple modes, including car, transit, bike and walk, on a second-by-second basis. Metropolitan planners must plan growth of their cities according to the stringent transportation system planning requirements of the Interniodal Surface Transportation Efficiency Act of 1991, the Clean Air Act Amendments of 1990 and other similar laws and regulations. These require each state and its metropotitan regions to work together to develop short and long term transportation improvement plans. The plans must (1) estimate the future transportation needs for travelers and goods movements, (2) evaluate ways to manage and reduce congestion, (3) examine the effectiveness of building new roads and transit systems, and (4) limit the environmental impact of the various strategies. The needed consistent and accurate transportation improvement plans require an analytical capability that properly accounts for travel demand, human behavior, traffic and transit operations, major investments, and environmental effects. Other existing planning tools use aggregated information and representative behavior to predict average response and average use of transportation facilities. They do not account

  15. Transportation Anslysis Simulation System

    Energy Science and Technology Software Center (ESTSC)

    2004-08-23

    TRANSIMS version 3.1 is an integrated set of analytical and simulation models and supporting databases. The system is designed to create a virtual metropolitan region with representation of each of the region’s individuals, their activities and the transportation infrastructure they use. TRANSIMS puts into practice a new, disaggregate approach to travel demand modeling using agent-based micro-simulation technology. TRANSIMS methodology creates a virtual metropolitan region with representation of the transportation infrastructure and the population, at themore » level of households and individual travelers. Trips a planned to satisfy the population’s activity pattems at the individual traveler level. TRANSIMS then simulates the movement of travelers and vehicles across the transportation network using multiple modes, including car, transit, bike and walk, on a second-by-second basis. Metropolitan planners must plan growth of their cities according to the stringent transportation system planning requirements of the Interniodal Surface Transportation Efficiency Act of 1991, the Clean Air Act Amendments of 1990 and other similar laws and regulations. These require each state and its metropotitan regions to work together to develop short and long term transportation improvement plans. The plans must (1) estimate the future transportation needs for travelers and goods movements, (2) evaluate ways to manage and reduce congestion, (3) examine the effectiveness of building new roads and transit systems, and (4) limit the environmental impact of the various strategies. The needed consistent and accurate transportation improvement plans require an analytical capability that properly accounts for travel demand, human behavior, traffic and transit operations, major investments, and environmental effects. Other existing planning tools use aggregated information and representative behavior to predict average response and average use of transportation facilities. They do not

  16. Simulation of wastewater treatment plant within integrated urban wastewater models.

    PubMed

    Heusch, S; Kamradt, B; Ostrowski, M

    2010-01-01

    In the federal state of Hesse in Germany the application of an integrated software modelling framework is becoming part of the planning process to attain legal approval for the operation of combined sewer systems. The software allows for parallel simulation of flow and water quality routing in the sewer system and in receiving rivers. It combines existing pollution load model approaches with a simplified version of the River Water Quality Model No. 1 (RWQM1). Comprehensive simulation of the wastewater treatment plant (WWTP) is not considered yet. The paper analyses alternatives for the implementation of a WWTP module to model activated sludge plants. For both primary and secondary clarifiers as well as for the activated sludge process concepts for the integration into the existing software framework were developed. The activated sludge concept which uses a linearized version of the well known ASM1 model is presented in detail. PMID:20453339

  17. Simulating neural systems with Xyce.

    SciTech Connect

    Schiek, Richard Louis; Thornquist, Heidi K.; Mei, Ting; Warrender, Christina E.; Aimone, James Bradley; Teeter, Corinne; Duda, Alex M.

    2012-12-01

    Sandia's parallel circuit simulator, Xyce, can address large scale neuron simulations in a new way extending the range within which one can perform high-fidelity, multi-compartment neuron simulations. This report documents the implementation of neuron devices in Xyce, their use in simulation and analysis of neuron systems.

  18. Designing a SCADA system simulator for fast breeder reactor

    NASA Astrophysics Data System (ADS)

    Nugraha, E.; Abdullah, A. G.; Hakim, D. L.

    2016-04-01

    SCADA (Supervisory Control and Data Acquisition) system simulator is a Human Machine Interface-based software that is able to visualize the process of a plant. This study describes the results of the process of designing a SCADA system simulator that aims to facilitate the operator in monitoring, controlling, handling the alarm, accessing historical data and historical trend in Nuclear Power Plant (NPP) type Fast Breeder Reactor (FBR). This research used simulation to simulate NPP type FBR Kalpakkam in India. This simulator was developed using Wonderware Intouch software 10 and is equipped with main menu, plant overview, area graphics, control display, set point display, alarm system, real-time trending, historical trending and security system. This simulator can properly simulate the principle of energy flow and energy conversion process on NPP type FBR. This SCADA system simulator can be used as training media for NPP type FBR prospective operators.

  19. [Signal systems of plant immunity].

    PubMed

    Dmitriev, A P

    2002-01-01

    Plants can recognise the penetrating pathogen and respond to the attack with an array of defense reactions. Signal transduction from receptor in plasma membrane to genome is necessary to activate these reactions. Plant cell signaling systems which take part in signal transduction were discovered and identified recently. The obtained results suggest that plant cells have complex and well coordinated signal network which regulates their immune potential. PMID:12187855

  20. Simulation of variation potential in higher plant cells.

    PubMed

    Sukhov, Vladimir; Akinchits, Elena; Katicheva, Lyubov; Vodeneev, Vladimir

    2013-04-01

    Variation potential (VP), a propagating electrical signal unique to plants, induces a number of changes in many physiological processes. However, the mechanisms of its generation and propagation are still under discussion and require experimental and theoretical analysis, including VP simulations. The mathematical model for VP formation in plants has been worked out and is based on our previous description of electrophysiological processes in higher plant cells, including plasma membrane ion transport systems (K(+), Cl(-) and Ca(2+) channels, H(+) and Ca(2+)-ATPase, 2H(+)/Cl(-) symporter and H(+)/K(+) antiporter) and their regulation, ion concentration changes in cells and extracellular spaces and buffers in cytoplasm and apoplast. In addition, the VP model takes into account wound substance diffusion, which is described by a one-dimensional diffusion equation, and ligand-gated Ca(2+) channels, which are activated by this substance. The VP model simulates the experimental dependence of amplitude, velocity and shape of VP on the distance from the wounding site and describes the influence of metabolic inhibitors, divalent cation chelators and anion channel blockers on the generation of this electrical reaction, as shown in experiments. Thus, our model favorably simulates VP in plants and theoretically supports the role of wound substance diffusion and Ca(2+) influx in VP development. PMID:23417063

  1. Bioaccumulation and Aquatic System Simulator

    EPA Science Inventory

    BASS (Bioaccumulation and Aquatic )System Simulator) is a Fortran 95 simulation program that predicts the population and bioaccumulation dynamics of age-structured fish assemblages that are exposed to hydrophobic organic pollutants and class B and bord...

  2. Priming in Systemic Plant Immunity

    SciTech Connect

    Jung, Ho Won; Tschaplinski, Timothy J; Wang, Lin; Glazebrook, Jane; Greenberg, Jean T.

    2009-01-01

    Upon local infection, plants possess inducible systemic defense responses against their natural enemies. Bacterial infection results in the accumulation to high levels of the mobile metabolite C9-dicarboxylic acid azelaic acid in the vascular sap of Arabidopsis. Azelaic acid confers local and systemic resistance against Pseudomonas syringae. The compound primes plants to strongly accumulate salicylic acid (SA), a known defense signal, upon infection. Mutation of a gene induced by azelaic acid (AZI1) results in the specific loss in plants of systemic immunity triggered by pathogen or azelaic acid and of the priming of SA induction. AZI1, a predicted secreted protein, is also important for generating vascular sap that confers disease resistance. Thus, azelaic acid and AZI1 comprise novel components of plant systemic immunity involved in priming defenses.

  3. Fossil power plant systems description

    SciTech Connect

    Not Available

    1984-01-01

    This single-volume, looseleaf text presents the functions and relationships between each major component and its auxiliaries within a system. The text also describes the relationships between systems. All major components are addressed, and system boundaries are defined for a generic fossil power plant.

  4. A COMPUTATIONAL WORKBENCH ENVIRONMENT FOR VIRTUAL POWER PLANT SIMULATION

    SciTech Connect

    Mike Bockelie; Dave Swensen; Martin Denison; Connie Senior; Adel Sarofim; Bene Risio

    2002-07-28

    This is the seventh Quarterly Technical Report for DOE Cooperative Agreement No.: DE-FC26-00NT41047. The goal of the project is to develop and demonstrate a computational workbench for simulating the performance of Vision 21 Power Plant Systems. Within the last quarter, good progress has been made on the development of the IGCC workbench. A series of parametric CFD simulations for single stage and two stage generic gasifier configurations have been performed. An advanced flowing slag model has been implemented into the CFD based gasifier model. A literature review has been performed on published gasification kinetics. Reactor models have been developed and implemented into the workbench for the majority of the heat exchangers, gas clean up system and power generation system for the Vision 21 reference configuration. Modifications to the software infrastructure of the workbench have been commenced to allow interfacing to the workbench reactor models that utilize the CAPE{_}Open software interface protocol.

  5. A COMPUTATIONAL WORKBENCH ENVIRONMENT FOR VIRTUAL POWER PLANT SIMULATION

    SciTech Connect

    Mike Bockelie; Dave Swensen; Martin Denison; Connie Senior; Zumao Chen; Temi Linjewile; Adel Sarofim; Bene Risio

    2003-04-25

    This is the tenth Quarterly Technical Report for DOE Cooperative Agreement No: DE-FC26-00NT41047. The goal of the project is to develop and demonstrate a computational workbench for simulating the performance of Vision 21 Power Plant Systems. Within the last quarter, good progress has been made on all aspects of the project. Calculations for a full Vision 21 plant configuration have been performed for two gasifier types. An improved process model for simulating entrained flow gasifiers has been implemented into the workbench. Model development has focused on: a pre-processor module to compute global gasification parameters from standard fuel properties and intrinsic rate information; a membrane based water gas shift; and reactors to oxidize fuel cell exhaust gas. The data visualization capabilities of the workbench have been extended by implementing the VTK visualization software that supports advanced visualization methods, including inexpensive Virtual Reality techniques. The ease-of-use, functionality and plug-and-play features of the workbench were highlighted through demonstrations of the workbench at a DOE sponsored coal utilization conference. A white paper has been completed that contains recommendations on the use of component architectures, model interface protocols and software frameworks for developing a Vision 21 plant simulator.

  6. Digital Full-Scope Simulation of a Conventional Nuclear Power Plant Control Room, Phase 2: Installation of a Reconfigurable Simulator to Support Nuclear Plant Sustainability

    SciTech Connect

    Ronald L. Boring; Vivek Agarwal; Kirk Fitzgerald; Jacques Hugo; Bruce Hallbert

    2013-03-01

    The U.S. Department of Energy’s Light Water Reactor Sustainability program has developed a control room simulator in support of control room modernization at nuclear power plants in the U.S. This report highlights the recent completion of this reconfigurable, full-scale, full-scope control room simulator buildout at the Idaho National Laboratory. The simulator is fully reconfigurable, meaning it supports multiple plant models developed by different simulator vendors. The simulator is full-scale, using glasstop virtual panels to display the analog control boards found at current plants. The present installation features 15 glasstop panels, uniquely achieving a complete control room representation. The simulator is also full-scope, meaning it uses the same plant models used for training simulators at actual plants. Unlike in the plant training simulators, the deployment on glasstop panels allows a high degree of customization of the panels, allowing the simulator to be used for research on the design of new digital control systems for control room modernization. This report includes separate sections discussing the glasstop panels, their layout to mimic control rooms at actual plants, technical details on creating a multi-plant and multi-vendor reconfigurable simulator, and current efforts to support control room modernization at U.S. utilities. The glasstop simulator provides an ideal testbed for prototyping and validating new control room concepts. Equally importantly, it is helping create a standardized and vetted human factors engineering process that can be used across the nuclear industry to ensure control room upgrades maintain and even improve current reliability and safety.

  7. Block Oriented Simulation System (BOSS)

    NASA Technical Reports Server (NTRS)

    Ratcliffe, Jaimie

    1988-01-01

    Computer simulation is assuming greater importance as a flexible and expedient approach to modeling system and subsystem behavior. Simulation has played a key role in the growth of complex, multiple access space communications such as those used by the space shuttle and the TRW-built Tracking and Data Relay Satellites (TDRS). A powerful new simulator for use in designing and modeling the communication system of NASA's planned Space Station is being developed. Progress to date on the Block (Diagram) Oriented Simulation System (BOSS) is described.

  8. System time-domain simulation

    NASA Technical Reports Server (NTRS)

    Dawson, C. T.; Eggleston, T. W.; Goris, A. C.; Fashano, M.; Paynter, D.; Tranter, W. H.

    1980-01-01

    Complex systems are simulated by engineers without extensive computer experience. Analyst uses free-form engineering-oriented language to input "black box" description. System Time Domain (SYSTID) Simulation Program generates appropriate algorithms and proceeds with simulation. Program is easily linked to postprocessing routines. SYSTID program is written in FORTRAN IV for batch execution and has been implemented on UNIVAC 1110 under control of EXEC 8, Level 31.

  9. Simulating The SSF Information System

    NASA Technical Reports Server (NTRS)

    Deshpande, Govind K.; Kleine, Henry; Younger, Joseph C.; Sanders, Felicia A.; Smith, Jeffrey L.; Aster, Robert W.; Olivieri, Jerry M.; Paul, Lori L.

    1993-01-01

    Freedom Operations Simulation Test (FROST) computer program simulates operation of SSF information system, tracking every packet of data from generation to destination, for both uplinks and downlinks. Collects various statistics concerning operation of system and provides reports of statistics at intervals specified by user. FROST also incorporates graphical-display capability to enhance interpretation of these statistics. Written in SIMSCRIPT 11.5.

  10. Water balance measurements and simulations of maize plants on lysimeters

    NASA Astrophysics Data System (ADS)

    Heinlein, Florian; Biernath, Christian; Klein, Christian; Thieme, Christoph; Priesack, Eckart

    2016-04-01

    simulated leaf area indexes (LAIs) at the beginning of the analyzed period. At the end of the measurement period, green LAI decreases and thus Tpot gets lower. At daily time steps transpiration simulated by SPASS agrees well with the measurements while CERES simulations overestimate Tact. Differences in ETact simulations compared to the lysimeter measurements mainly occur due to the different choice of ETpot-models. In conclusion, with the help of canopy models the water balance of the lysimeter system can be reasonably well simulated. However, the applied crop models oversimplify plant water transport and thus may not describe the water uptake and hence crop growth dynamics well enough for application of expected future climate scenarios.

  11. Plant-wide dynamic simulation of an IGCC plant with CO2 capture

    SciTech Connect

    Bhattacharyya, D.; Turton, R.; Zitney, S.

    2009-01-01

    To eliminate the harmful effects of greenhouse gases, especially that of CO2, future coalfired power plants need to consider the option for CO2 capture. The loss in efficiency for CO2 capture is less in an Integrated Gasification Combined Cycle (IGCC) plant compared to other conventional coal combustion processes. However, no IGCC plant with CO2 capture currently exists in the world. Therefore, it is important to consider the operability and controllability issues of such a plant before it is commercially built. With this objective in mind, a detailed plant-wide dynamic simulation of an IGCC plant with CO2 capture has been developed. The plant considers a General Electric Energy (GEE)-type downflow radiant-only gasifier followed by a quench section. A two-stage water gas shift (WGS) reaction is considered for conversion of about 96 mol% of CO to CO2. A two-stage acid gas removal (AGR) process based on a physical solvent is simulated for selective capture of H2S and CO2. The clean syngas is sent to a gas turbine (GT) followed by a heat recovery steam generator (HRSG). The steady state results are validated with data from a commercial gasifier. A 5 % ramp increase in the flowrate of coal is introduced to study the system dynamics. To control the conversion of CO at a desired level in the WGS reactors, the steam/CO ratio is manipulated. This strategy is found to be efficient for this operating condition. In the absence of an efficient control strategy in the AGR process, the environmental emissions exceeded the limits by a great extent.

  12. A COMPUTATIONAL WORKBENCH ENVIRONMENT FOR VIRTUAL POWER PLANT SIMULATION

    SciTech Connect

    Mike Bockelie; Dave Swensen; Martin Denison; Connie Senior; Zumao Chen; Temi Linjewile; Adel Sarofim; Bene Risio

    2003-01-25

    This is the eighth Quarterly Technical Report for DOE Cooperative Agreement No: DE-FC26-00NT41047. The goal of the project is to develop and demonstrate a computational workbench for simulating the performance of Vision 21 Power Plant Systems. Within the last quarter, good progress has been made on all aspects of the project. Calculations for a full Vision 21 plant configuration have been performed for two coal types and two gasifier types. Good agreement with DOE computed values has been obtained for the Vision 21 configuration under ''baseline'' conditions. Additional model verification has been performed for the flowing slag model that has been implemented into the CFD based gasifier model. Comparisons for the slag, wall and syngas conditions predicted by our model versus values from predictive models that have been published by other researchers show good agreement. The software infrastructure of the Vision 21 workbench has been modified to use a recently released, upgraded version of SCIRun.

  13. Healthcare system simulation using Witness

    NASA Astrophysics Data System (ADS)

    Khakdaman, Masoud; Zeinahvazi, Milad; Zohoori, Bahareh; Nasiri, Fardokht; Yew Wong, Kuan

    2013-02-01

    Simulation techniques have a proven track record in manufacturing industry as well as other areas such as healthcare system improvement. In this study, simulation model of a health center in Malaysia is developed through the application of WITNESS simulation software which has shown its flexibility and capability in manufacturing industry. Modelling procedure is started through process mapping and data collection and continued with model development, verification, validation and experimentation. At the end, final results and possible future improvements are demonstrated.

  14. A COMPUTATIONAL WORKBENCH ENVIRONMENT FOR VIRTUAL POWER PLANT SIMULATION

    SciTech Connect

    Mike Bockelie; Dave Swensen; Martin Denison

    2002-01-31

    This is the fifth Quarterly Technical Report for DOE Cooperative Agreement No: DE-FC26-00NT41047. The goal of the project is to develop and demonstrate a computational workbench for simulating the performance of Vision 21 Power Plant Systems. Within the last quarter, our efforts have become focused on developing an improved workbench for simulating a gasifier based Vision 21 energyplex. To provide for interoperability of models developed under Vision 21 and other DOE programs, discussions have been held with DOE and other organizations developing plant simulator tools to review the possibility of establishing a common software interface or protocol to use when developing component models. A component model that employs the CCA protocol has successfully been interfaced to our CCA enabled workbench. To investigate the software protocol issue, DOE has selected a gasifier based Vision 21 energyplex configuration for use in testing and evaluating the impacts of different software interface methods. A Memo of Understanding with the Cooperative Research Centre for Coal in Sustainable Development (CCSD) in Australia has been completed that will enable collaborative research efforts on gasification issues. Preliminary results have been obtained for a CFD model of a pilot scale, entrained flow gasifier. A paper was presented at the Vision 21 Program Review Meeting at NETL (Morgantown) that summarized our accomplishments for Year One and plans for Year Two and Year Three.

  15. A multiprocessor operating system simulator

    SciTech Connect

    Johnston, G.M.; Campbell, R.H. . Dept. of Computer Science)

    1988-01-01

    This paper describes a multiprocessor operating system simulator that was developed by the authors in the Fall of 1987. The simulator was built in response to the need to provide students with an environment in which to build and test operating system concepts as part of the coursework of a third-year undergraduate operating systems course. Written in C++, the simulator uses the co-routine style task package that is distributed with the AT and T C++ Translator to provide a hierarchy of classes that represents a broad range of operating system software and hardware components. The class hierarchy closely follows that of the Choices family of operating systems for loosely and tightly coupled multiprocessors. During an operating system course, these classes are refined and specialized by students in homework assignments to facilitate experimentation with different aspects of operating system design and policy decisions. The current implementation runs on the IBM RT PC under 4.3bsd UNIX.

  16. A Multiprocessor Operating System Simulator

    NASA Technical Reports Server (NTRS)

    Johnston, Gary M.; Campbell, Roy H.

    1988-01-01

    This paper describes a multiprocessor operating system simulator that was developed by the authors in the Fall semester of 1987. The simulator was built in response to the need to provide students with an environment in which to build and test operating system concepts as part of the coursework of a third-year undergraduate operating systems course. Written in C++, the simulator uses the co-routine style task package that is distributed with the AT&T C++ Translator to provide a hierarchy of classes that represents a broad range of operating system software and hardware components. The class hierarchy closely follows that of the 'Choices' family of operating systems for loosely- and tightly-coupled multiprocessors. During an operating system course, these classes are refined and specialized by students in homework assignments to facilitate experimentation with different aspects of operating system design and policy decisions. The current implementation runs on the IBM RT PC under 4.3bsd UNIX.

  17. Using a data-assimilation system to assess the influence of fire on simulated carbon fluxes and plant traits for the Australian continent

    NASA Astrophysics Data System (ADS)

    Exbrayat, Jean-François; Smallman, T. Luke; Bloom, A. Anthony; Williams, Mathew

    2015-04-01

    Natural disturbances, such as fire, play an important role in the carbon balance of terrestrial ecosystems. Both burned emissions and the impact of fire on plant growth must be considered to quantify the magnitude of the current and future terrestrial carbon sink. However, fire is rarely represented in Earth System Models, and the usual classification of ecosystems in a limited number of global plant functional types does not take into account local adaptations to fire regimes that enable resilience of ecosystems. We show the importance of these mechanisms with a terrestrial model-data fusion scheme applied to the fire-prone Australian continent. We use the CARbon DAta-MOdel fraMework (CARDAMOM) to assimilate time series of MODIS LAI and GFED burned area and use the Harmonized World Soil Database and remote-sensing based estimates of Above-Ground Biomass as prior knowledge for initial conditions. In each pixel, a Markov Chain Monte-Carlo algorithm is used to optimise parameters according to observations. Meanwhile, ecological and dynamical constraints representative of real world processes constrain parameter inter-dependencies and long-term pool dynamics. CARDAMOM outputs maps of ecosystem carbon fluxes and parameters as well as their uncertainty sampled from the posterior distribution provided by the MCMC. We perform two data-assimilations over Australia. The first experiment is a control run that includes fire drivers while the second experiment does not consider the occurrence of fires. Results of the first experiment are comparable to previous estimates and show that Australian ecosystems have most likely been acting as a carbon sink since the year 2000 with a large fire-driven inter-annual variability (best estimate of 264 ± 172 Tg C yr-1). However, our results indicate that the most intense fire seasons may temporarily turn the continent into a net source of carbon offsetting the natural carbon sink of the same year. Comparing the parameter maps generated

  18. Developing Higher Plant Systems in Space

    NASA Technical Reports Server (NTRS)

    Krikorian, A. D.

    1983-01-01

    The effects of hypogravity and microgravity environments on plant cells are discussed. Experiments on embryos of carrots are discussed. Simulation and spacecraft environments were used in experiments.

  19. IMPROVING TACONITE PROCESSING PLANT EFFICIENCY BY COMPUTER SIMULATION, Final Report

    SciTech Connect

    William M. Bond; Salih Ersayin

    2007-03-30

    This project involved industrial scale testing of a mineral processing simulator to improve the efficiency of a taconite processing plant, namely the Minorca mine. The Concentrator Modeling Center at the Coleraine Minerals Research Laboratory, University of Minnesota Duluth, enhanced the capabilities of available software, Usim Pac, by developing mathematical models needed for accurate simulation of taconite plants. This project provided funding for this technology to prove itself in the industrial environment. As the first step, data representing existing plant conditions were collected by sampling and sample analysis. Data were then balanced and provided a basis for assessing the efficiency of individual devices and the plant, and also for performing simulations aimed at improving plant efficiency. Performance evaluation served as a guide in developing alternative process strategies for more efficient production. A large number of computer simulations were then performed to quantify the benefits and effects of implementing these alternative schemes. Modification of makeup ball size was selected as the most feasible option for the target performance improvement. This was combined with replacement of existing hydrocyclones with more efficient ones. After plant implementation of these modifications, plant sampling surveys were carried out to validate findings of the simulation-based study. Plant data showed very good agreement with the simulated data, confirming results of simulation. After the implementation of modifications in the plant, several upstream bottlenecks became visible. Despite these bottlenecks limiting full capacity, concentrator energy improvement of 7% was obtained. Further improvements in energy efficiency are expected in the near future. The success of this project demonstrated the feasibility of a simulation-based approach. Currently, the Center provides simulation-based service to all the iron ore mining companies operating in northern

  20. High-speed simulation of transients in nuclear power plants

    SciTech Connect

    Wulff, W.; Cheng, H.S.; Lekach, S.V.; Mallen, A.N.

    1984-01-01

    A combination of advanced modeling techniques and modern, special-purpose peripheral minicomputer technology is presented which affords realistic predictions of plant transient and severe off-normal events in LWR power plants through on-line simulations at a speed ten times greater than actual process speeds. Results are shown for a BWR plant simulation. Results are shown to demonstrate computing capacity, accuracy, and speed. Simulation speeds have been achieved which are 110 times larger than those of a CDC-7600 mainframe computer or ten times greater than real-time speed.

  1. A model for plant lighting system selection

    NASA Technical Reports Server (NTRS)

    Ciolkosz, D. E.; Albright, L. D.; Sager, J. C.; Langhans, R. W.

    2002-01-01

    A decision model is presented that compares lighting systems for a plant growth scenario and chooses the most appropriate system from a given set of possible choices. The model utilizes a Multiple Attribute Utility Theory approach, and incorporates expert input and performance simulations to calculate a utility value for each lighting system being considered. The system with the highest utility is deemed the most appropriate system. The model was applied to a greenhouse scenario, and analyses were conducted to test the model's output for validity. Parameter variation indicates that the model performed as expected. Analysis of model output indicates that differences in utility among the candidate lighting systems were sufficiently large to give confidence that the model's order of selection was valid.

  2. Solar power plant performance evaluation: simulation and experimental validation

    NASA Astrophysics Data System (ADS)

    Natsheh, E. M.; Albarbar, A.

    2012-05-01

    In this work the performance of solar power plant is evaluated based on a developed model comprise photovoltaic array, battery storage, controller and converters. The model is implemented using MATLAB/SIMULINK software package. Perturb and observe (P&O) algorithm is used for maximizing the generated power based on maximum power point tracker (MPPT) implementation. The outcome of the developed model are validated and supported by a case study carried out using operational 28.8kW grid-connected solar power plant located in central Manchester. Measurements were taken over 21 month's period; using hourly average irradiance and cell temperature. It was found that system degradation could be clearly monitored by determining the residual (the difference) between the output power predicted by the model and the actual measured power parameters. It was found that the residual exceeded the healthy threshold, 1.7kW, due to heavy snow in Manchester last winter. More important, the developed performance evaluation technique could be adopted to detect any other reasons that may degrade the performance of the P V panels such as shading and dirt. Repeatability and reliability of the developed system performance were validated during this period. Good agreement was achieved between the theoretical simulation and the real time measurement taken the online grid connected solar power plant.

  3. [Simulation of bacteria-plant coevolution in the mutualistic symbiosis].

    PubMed

    Provorov, N A; Vorob'ev, N I

    2009-05-01

    We present the mathematical model for coevolution of root nodule bacteria (rhizobia) and leguminous plants which is based on the partners' positive feedbacks resulted from their metabolic integration. The model parameters were introduced which determine: 1) coordinated changes in plant and bacterial population structures; 2) increase of fitness (reproductive potentials) in both partners as dependent on the symbiotic efficiency determined by proportion of N2-fixing rhizobia strain in root nodules. Computer experiments demonstrated that microevolution of the simulated system may follow either oscillatory or quasi-monotonous regime as dependent of frequency-dependent selection (FDS) in plant population. Negative FDS occurring in the bacterial population during competition for nodulation in combination with the positive partners' feedback may lead to anchoring the bacterial mutations which lead either to acquisition of mutualistic traits or to changes in specificity of their expression. Anchoring of the mutualistic strains occurs most successfully in the quasi-monotonous regime and results in the improvement of genetic stability in symbiotic system. PMID:19534417

  4. DSC: software tool for simulation-based design of control strategies applied to wastewater treatment plants.

    PubMed

    Ruano, M V; Ribes, J; Seco, A; Ferrer, J

    2011-01-01

    This paper presents a computer tool called DSC (Simulation based Controllers Design) that enables an easy design of control systems and strategies applied to wastewater treatment plants. Although the control systems are developed and evaluated by simulation, this tool aims to facilitate the direct implementation of the designed control system to the PC of the full-scale WWTP (wastewater treatment plants). The designed control system can be programmed in a dedicated control application and can be connected to either the simulation software or the SCADA of the plant. To this end, the developed DSC incorporates an OPC server (OLE for process control) which facilitates an open-standard communication protocol for different industrial process applications. The potential capabilities of the DSC tool are illustrated through the example of a full-scale application. An aeration control system applied to a nutrient removing WWTP was designed, tuned and evaluated with the DSC tool before its implementation in the full scale plant. The control parameters obtained by simulation were suitable for the full scale plant with only few modifications to improve the control performance. With the DSC tool, the control systems performance can be easily evaluated by simulation. Once developed and tuned by simulation, the control systems can be directly applied to the full-scale WWTP. PMID:21330730

  5. Simulation of existing gas-fuelled conventional steam power plant using Cycle Tempo

    NASA Astrophysics Data System (ADS)

    Jamel, M. S.; Abd Rahman, A.; Shamsuddin, A. H.

    2013-06-01

    Simulation of a 200 MW gas-fuelled conventional steam power plant located in Basra, Iraq was carried out. The thermodynamic performance of the considered power plant is estimated by a system simulation. A flow-sheet computer program, "Cycle-Tempo" is used for the study. The plant components and piping systems were considered and described in detail. The simulation results were verified against data gathered from the log sheet obtained from the station during its operation hours and good results were obtained. Operational factors like the stack exhaust temperature and excess air percentage were studied and discussed, as were environmental factors, such as ambient air temperature and water inlet temperature. In addition, detailed exergy losses were illustrated and describe the temperature profiles for the main plant components. The results prompted many suggestions for improvement of the plant performance.

  6. Large-Eddy Simulation of Wind-Plant Aerodynamics

    SciTech Connect

    Churchfield, M. J.; Lee, S.; Moriarty, P. J.; Martinez, L. A.; Leonardi, S.; Vijayakumar, G.; Brasseur, J. G.

    2012-01-01

    In this work, we present results of a large-eddy simulation of the 48 multi-megawatt turbines composing the Lillgrund wind plant. Turbulent inflow wind is created by performing an atmospheric boundary layer precursor simulation, and turbines are modeled using a rotating, variable-speed actuator line representation. The motivation for this work is that few others have done large-eddy simulations of wind plants with a substantial number of turbines, and the methods for carrying out the simulations are varied. We wish to draw upon the strengths of the existing simulations and our growing atmospheric large-eddy simulation capability to create a sound methodology for performing this type of simulation. We used the OpenFOAM CFD toolbox to create our solver. The simulated time-averaged power production of the turbines in the plant agrees well with field observations, except with the sixth turbine and beyond in each wind-aligned. The power produced by each of those turbines is overpredicted by 25-40%. A direct comparison between simulated and field data is difficult because we simulate one wind direction with a speed and turbulence intensity characteristic of Lillgrund, but the field observations were taken over a year of varying conditions. The simulation shows the significant 60-70% decrease in the performance of the turbines behind the front row in this plant that has a spacing of 4.3 rotor diameters in this direction. The overall plant efficiency is well predicted. This work shows the importance of using local grid refinement to simultaneously capture the meter-scale details of the turbine wake and the kilometer-scale turbulent atmospheric structures. Although this work illustrates the power of large-eddy simulation in producing a time-accurate solution, it required about one million processor-hours, showing the significant cost of large-eddy simulation.

  7. Simulation-based biagnostics and control for nuclar power plants

    SciTech Connect

    Lee, J.C.

    1993-01-01

    Advanced simulation-based diagnostics and control guidance systems for the identification and management of off-normal transient events in nuclear power plants is currently under investigation. To date a great deal of progress has been made in effectively and efficiently combining information obtained through fuzzy pattern recognition and macroscopic mass and energy inventory analysis for use in multiple failure diagnostics. Work has also begun on the unique problem of diagnostics and surveillance methodologies for advanced passively-safe reactors systems utilizing both statistical and fuzzy information. Plans are also being formulated for the development of deterministic optimal control algorithms combined with Monte Carlo incremental learning algorithms to be used for the flexible and efficient control of reactor transients.

  8. Large-Eddy Simulation of Wind-Plant Aerodynamics: Preprint

    SciTech Connect

    Churchfield, M. J.; Lee, S.; Moriarty, P. J.; Martinez, L. A.; Leonardi, S.; Vijayakumar, G.; Brasseur, J. G.

    2012-01-01

    In this work, we present results of a large-eddy simulation of the 48 multi-megawatt turbines composing the Lillgrund wind plant. Turbulent inflow wind is created by performing an atmospheric boundary layer precursor simulation and turbines are modeled using a rotating, variable-speed actuator line representation. The motivation for this work is that few others have done wind plant large-eddy simulations with a substantial number of turbines, and the methods for carrying out the simulations are varied. We wish to draw upon the strengths of the existing simulations and our growing atmospheric large-eddy simulation capability to create a sound methodology for performing this type of simulation. We have used the OpenFOAM CFD toolbox to create our solver.

  9. Simulating Groundwater-Plant-Atmosphere Interactions in a Semiarid Savanna

    NASA Astrophysics Data System (ADS)

    Gou, S.; Miller, G. R.

    2013-12-01

    Groundwater serves as one of the main water sources for deep rooted phreatophytic vegetation. Such vegetation acts as the linkage between groundwater, land surface and atmosphere. Through plant groundwater uptake and hydraulic redistribution (HR), the dynamics of relatively deep groundwater can influence ET and soil moisture of top soil layers. In this work, we first developed a plant scale model to simulate groundwater uptake and HR driven by the potential gradients along the groundwater-soil-plant-atmosphere continuum (GSPAC). The model included a new plant water stress function based on the 'vulnerability curve' theory in order to integrate the influences of both soil water and groundwater on transpiration. The model was calibrated and validated with measured ET, soil moisture, and leaf water potential data and was able to capture both energy and water dynamics along the GSPAC. We then coupled this plant scale model into a spatial distributed groundwater-land surface model (ParFlow.CLM). The revisions to ParFlow.CLM allow it to explicitly describe root water uptake and HR of different species, allowing for the study of how plant groundwater use and HR influence regional water budget and climate. This new uptake formulation was applied to simulate a heterogeneous savanna system at an AmeriFlux site in California. The site is dominated by blue oaks which can access both soil water and groundwater and grasses which only depend on soil water. The results match previous field measurements indicating that the oaks use most soil water during wet season and switch to groundwater use in dry season to buffer the impacts of drought. Therefore, the water and energy dynamics at this site showed the soil moisture controlled pattern in wet season, and the vegetation and groundwater controlled pattern in dry season. With HR, the rainfall is distributed into deeper soil in wet season by hydraulic descent. Such water will be lifted into shallower soil to promote transpiration in

  10. MCFC and microturbine power plant simulation

    NASA Astrophysics Data System (ADS)

    Orecchini, F.; Bocci, E.; Di Carlo, A.

    The consistent problem of the CO 2 emissions and the necessity to find new energy sources, are motivating the scientific research to use high efficiency electric energy production's technologies that could exploit renewable energy sources too. The molten carbonate fuel cell (MCFC) due to its high efficiencies and low emissions seems a valid alternative to the traditional plant. Moreover, the high operating temperature and pressure give the possibility to use a turbine at the bottom of the cells to produce further energy, increasing therefore the plant's efficiencies. The basic idea using this two kind of technologies (MCFC and microturbine), is to recover, via the microturbine, the necessary power for the compressor, that otherwise would remove a consistent part of the MCFC power generated. The purpose of this work is to develop the necessary models to analyze different plant configurations. In particular, it was studied a plant composed of a MCFC 500 kW Ansaldo at the top of a microturbine 100 kW Turbec. To study this plant it was necessary to develop: (i) MCFC mathematical model, that starting from the geometrical and thermofluidodynamic parameter of the cell, analyze the electrochemical reaction and shift reaction that take part in it; (ii) plate reformer model, a particular compact reformer that exploit the heat obtained by a catalytic combustion of the anode and part of cathode exhausts to reform methane and steam; and (iii) microturbine-compressor model that describe the efficiency and pressure ratio of the two machines as a function of the mass flow and rotational regime. The models developed was developed in Fortran language and interfaced in Chemcad © to analyze the power plant thermodynamic behavior. The results show a possible plant configuration with high electrical and global efficiency (over 50 and 74%).

  11. The Airspace Concepts Evaluation System Architecture and System Plant

    NASA Technical Reports Server (NTRS)

    Windhorst, Robert; Meyn, Larry; Manikonda, Vikram; Carlos, Patrick; Capozzi, Brian

    2006-01-01

    The Airspace Concepts Evaluation System is a simulation of the National Airspace System. It includes models of flights, airports, airspaces, air traffic controls, traffic flow managements, and airline operation centers operating throughout the United States. It is used to predict system delays in response to future capacity and demand scenarios and perform benefits assessments of current and future airspace technologies and operational concepts. Facilitation of these studies requires that the simulation architecture supports plug and play of different air traffic control, traffic flow management, and airline operation center models and multi-fidelity modeling of flights, airports, and airspaces. The simulation is divided into two parts that are named, borrowing from classical control theory terminology, control and plant. The control consists of air traffic control, traffic flow management, and airline operation center models, and the plant consists of flight, airport, and airspace models. The plant can run open loop, in the absence of the control. However, undesired affects, such as conflicts and over congestions in the airspaces and airports, can occur. Different controls are applied, "plug and played", to the plant. A particular control is evaluated by analyzing how well it managed conflicts and congestions. Furthermore, the terminal area plants consist of models of airports and terminal airspaces. Each model consists of a set of nodes and links which are connected by the user to form a network. Nodes model runways, fixes, taxi intersections, gates, and/or other points of interest, and links model taxiways, departure paths, and arrival paths. Metering, flow distribution, and sequencing functions can be applied at nodes. Different fidelity model of how a flight transits are can be used by links. The fidelity of the model can be adjusted by the user by either changing the complexity of the node/link network-or the way that the link models how the flights transit

  12. "Orpheus" cardiopulmonary bypass simulation system.

    PubMed

    Morris, Richard W; Pybus, David A

    2007-12-01

    In this paper we describe a high-fidelity perfusion simulation system intended for use in the training and continuing education of perfusionists. The system comprises a hydraulic simulator, an electronic interface unit and a controlling computer with associated real-time computer models. It is designed for use within an actual operating theatre, or within a specialized simulation facility. The hydraulic simulator can be positioned on an operating table and physically connected to the circuit of the institutional heart-lung machine. The institutional monitoring system is used to display the arterial and central venous pressures, the ECG and the nasopharyngeal temperature using appropriate connections. The simulator is able to reproduce the full spectrum of normal and abnormal events that may present during the course of cardiopulmonary bypass. The system incorporates a sophisticated blood gas model that accurately predicts the behavior of a modern, hollow-fiber oxygenator. Output from this model is displayed in the manner of an in-line blood gas electrode and is updated every 500 msecs. The perfusionist is able to administer a wide variety of drugs during a simulation session including: vasoconstrictors (metaraminol, epinephrine and phenylephrine), a vasodilator (sodium nitroprusside), chronotropes (epinephrine and atropine), an inotrope (epinephrine) and modifiers of coagulation (heparin and protamine). Each drug has a pharmacokinetic profile based on a three-compartment model plus an effect compartment. The simulation system has potential roles in the skill training of perfusionists, the development of crisis management protocols, the certification and accreditation of perfusionists and the evaluation of new perfusion equipment and/or techniques. PMID:18293807

  13. LED Systems Target Plant Growth

    NASA Technical Reports Server (NTRS)

    2010-01-01

    To help develop technologies for growing edible biomass (food crops) in space, Kennedy Space Center partnered with Orbital Technologies Corporation (ORBITEC), of Madison, Wisconsin, through the Small Business Innovation Research (SBIR) program. One result of this research was the High Efficiency Lighting with Integrated Adaptive Control (HELIAC) system, components of which have been incorporated into a variety of agricultural greenhouse and consumer aquarium lighting features. The new lighting systems can be adapted to a specific plant species during a specific growth stage, allowing maximum efficiency in light absorption by all available photosynthetic tissues.

  14. Current Water Deficit Stress Simulations in Selected Agricultural System Simulation Models

    Technology Transfer Automated Retrieval System (TEKTRAN)

    System models, which adequately simulate plant water stress effects, are valuable tools for developing management practices with improved water use efficiency in agriculture. Plants experience water stress when its supply in the soil fails to meet the demand. Although it is easy to define the conc...

  15. Systems Engineering Simulator (SES) Simulator Planning Guide

    NASA Technical Reports Server (NTRS)

    McFarlane, Michael

    2011-01-01

    The simulation process, milestones and inputs are unknowns to first-time users of the SES. The Simulator Planning Guide aids in establishing expectations for both NASA and non-NASA facility customers. The potential audience for this guide includes both internal and commercial spaceflight hardware/software developers. It is intended to assist their engineering personnel in simulation planning and execution. Material covered includes a roadmap of the simulation process, roles and responsibilities of facility and user, major milestones, facility capabilities, and inputs required by the facility. Samples of deliverables, facility interfaces, and inputs necessary to define scope, cost, and schedule are included as an appendix to the guide.

  16. Plant Reaction on the Influence of Antistress Substances in Simulated Microgravity

    NASA Astrophysics Data System (ADS)

    Mishchenko, L. T.; Reshetnyk, G. V.; Koreneva, A. A.

    2008-06-01

    On conditions of the simulated microgravity investigated influence of growth regulated matters - phenol-containing agent of natural origin - dublin and oxide of peat on the decline of stress at plants. Found out positive influence of phenol-containing preparations on the increase of firmness of wheat plants to stress conditions of clinorotation. Thereby, alternations of virus-host-plant system in wheat plants take place and reactions of adaptation are formed under microgravity conditions. Just these reactions lead to reduction of reproduction of wheat streak mosaic virus. The phenomenon may be used for the treatment of medicinal plants against viral infections.

  17. Chitosan Effects on Plant Systems

    PubMed Central

    Malerba, Massimo; Cerana, Raffaella

    2016-01-01

    Chitosan (CHT) is a natural, safe, and cheap product of chitin deacetylation, widely used by several industries because of its interesting features. The availability of industrial quantities of CHT in the late 1980s enabled it to be tested in agriculture. CHT has been proven to stimulate plant growth, to protect the safety of edible products, and to induce abiotic and biotic stress tolerance in various horticultural commodities. The stimulating effect of different enzyme activities to detoxify reactive oxygen species suggests the involvement of hydrogen peroxide and nitric oxide in CHT signaling. CHT could also interact with chromatin and directly affect gene expression. Recent innovative uses of CHT include synthesis of CHT nanoparticles as a valuable delivery system for fertilizers, herbicides, pesticides, and micronutrients for crop growth promotion by a balanced and sustained nutrition. In addition, CHT nanoparticles can safely deliver genetic material for plant transformation. This review presents an overview on the status of the use of CHT in plant systems. Attention was given to the research that suggested the use of CHT for sustainable crop productivity. PMID:27347928

  18. Chitosan Effects on Plant Systems.

    PubMed

    Malerba, Massimo; Cerana, Raffaella

    2016-01-01

    Chitosan (CHT) is a natural, safe, and cheap product of chitin deacetylation, widely used by several industries because of its interesting features. The availability of industrial quantities of CHT in the late 1980s enabled it to be tested in agriculture. CHT has been proven to stimulate plant growth, to protect the safety of edible products, and to induce abiotic and biotic stress tolerance in various horticultural commodities. The stimulating effect of different enzyme activities to detoxify reactive oxygen species suggests the involvement of hydrogen peroxide and nitric oxide in CHT signaling. CHT could also interact with chromatin and directly affect gene expression. Recent innovative uses of CHT include synthesis of CHT nanoparticles as a valuable delivery system for fertilizers, herbicides, pesticides, and micronutrients for crop growth promotion by a balanced and sustained nutrition. In addition, CHT nanoparticles can safely deliver genetic material for plant transformation. This review presents an overview on the status of the use of CHT in plant systems. Attention was given to the research that suggested the use of CHT for sustainable crop productivity. PMID:27347928

  19. Plant Closings and Capital Flight: A Computer-Assisted Simulation.

    ERIC Educational Resources Information Center

    Warner, Stanley; Breitbart, Myrna M.

    1989-01-01

    A course at Hampshire College was designed to simulate the decision-making environment in which constituencies in a medium-sized city would respond to the closing and relocation of a major corporate plant. The project, constructed as a role simulation with a computer component, is described. (MLW)

  20. Simulating Leaf Area of Corn Plants at Contrasting Water Status

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An exponential decay function was fitted with literature data to describe the decrease in leaf expansion rate as leaf water potential decreases. The fitted function was then applied to modify an existing leaf area simulation module in a soil-plant-atmosphere continuum model in order to simulate leaf...

  1. Total simulation of operator team behavior in emergencies at nuclear power plants.

    PubMed

    Takano, K; Sunaoshi, W; Suzuki, K

    2000-09-01

    In a large and complex system (i.e., a space aeronautics and nuclear power plant) it would be valuable to conduct operator training and support to demonstrate standard operators' behavior in coping with an anomaly caused by multiple malfunctions in which procedures would not have been stipulated previously. A system simulating operator team behavior including individual operator's cognitive behavior, his operations and physical behavior, and even verbal communication among team members, has been developed for a typical commercial nuclear power plant. This simulation model is not a scenario-based system but a complete knowledge-based system, based on the mental model that was envisaged by detailed analyses of experimental results obtained in the full-scope plant simulator. This mental model is composed of a set of knowledge bases and rules able to generate both diagnosis and prognosis depending on the observed situation even for multiple malfunctions. Simulation results of operator team behavior and plant dynamics were compared with corresponding experiments in several anomalies of multiple malfunctions. The comparison showed a reasonable agreement, so the simulation conditions were varied on cognitive task processing speed of individual operators, on team role sharing scheme, and on human machine interface (1st generation to 2nd generation control panel) to assess the sensitivity of this simulation model. Finally, it was shown that this simulation model has applications for the use of training standards and computer aided operator support systems. PMID:10993327

  2. A COMPUTATIONAL WORKBENCH ENVIRONMENT FOR VIRTUAL POWER PLANT SIMULATION

    SciTech Connect

    Mike Bockelie; Dave Swensen; Martin Denison

    2002-04-30

    This is the sixth Quarterly Technical Report for DOE Cooperative Agreement No: DE-FC26-00NT41047. The goal of the project is to develop and demonstrate a computational workbench for simulating the performance of Vision 21 Power Plant Systems. Within the last quarter, good progress has been made on the development of our IGCC workbench. Preliminary CFD simulations for single stage and two stage ''generic'' gasifiers using firing conditions based on the Vision 21 reference configuration have been performed. Work is continuing on implementing an advanced slagging model into the CFD based gasifier model. An investigation into published gasification kinetics has highlighted a wide variance in predicted performance due to the choice of kinetic parameters. A plan has been outlined for developing the reactor models required to simulate the heat transfer and gas clean up equipment downstream of the gasifier. Three models that utilize the CCA software protocol have been integrated into a version of the IGCC workbench. Tests of a CCA implementation of our CFD code into the workbench demonstrated that the CCA CFD module can execute on a geographically remote PC (linked via the Internet) in a manner that is transparent to the user. Software tools to create ''walk-through'' visualizations of the flow field within a gasifier have been demonstrated.

  3. Dynamic simulation of a direct carbonate fuel cell power plant

    SciTech Connect

    Ernest, J.B.; Ghezel-Ayagh, H.; Kush, A.K.

    1996-12-31

    Fuel Cell Engineering Corporation (FCE) is commercializing a 2.85 MW Direct carbonate Fuel Cell (DFC) power plant. The commercialization sequence has already progressed through construction and operation of the first commercial-scale DFC power plant on a U.S. electric utility, the 2 MW Santa Clara Demonstration Project (SCDP), and the completion of the early phases of a Commercial Plant design. A 400 kW fuel cell stack Test Facility is being built at Energy Research Corporation (ERC), FCE`s parent company, which will be capable of testing commercial-sized fuel cell stacks in an integrated plant configuration. Fluor Daniel, Inc. provided engineering, procurement, and construction services for SCDP and has jointly developed the Commercial Plant design with FCE, focusing on the balance-of-plant (BOP) equipment outside of the fuel cell modules. This paper provides a brief orientation to the dynamic simulation of a fuel cell power plant and the benefits offered.

  4. Simulation of solar chimney power plant with an external heat source

    NASA Astrophysics Data System (ADS)

    Islamuddin, Azeemuddin; Al-Kayiem, Hussain H.; Gilani, Syed I.

    2013-06-01

    Solar chimney power plant is a sustainable source of power production. The key parameter to increase the system power output is to increase its size but the plant cannot operate during night hours. This study deals with simulation work to validate results of pilot plant at Manzanares and include the effects of waste heat from a gas turbine power plant in the system. The effects show continuous night operation, a 38.8 percent increase in power at 1000 W/m2 global solar irradiation at daytime and 1.14 percent increase in overall efficiency.

  5. Real time digital propulsion system simulation for manned flight simulators

    NASA Technical Reports Server (NTRS)

    Mihaloew, J. R.; Hart, C. E.

    1978-01-01

    A real time digital simulation of a STOL propulsion system was developed which generates significant dynamics and internal variables needed to evaluate system performance and aircraft interactions using manned flight simulators. The simulation ran at a real-to-execution time ratio of 8.8. The model was used in a piloted NASA flight simulator program to evaluate the simulation technique and the propulsion system digital control. The simulation is described and results shown. Limited results of the flight simulation program are also presented.

  6. Systems simulations supporting NASA telerobotics

    NASA Technical Reports Server (NTRS)

    Harrison, F. W., Jr.; Pennington, J. E.

    1987-01-01

    Two simulation and analysis environments have been developed to support telerobotics research at the Langley Research Center. One is a high-fidelity, nonreal-time, interactive model called ROBSIM, which combines user-generated models of workspace environment, robots, and loads into a working system and simulates the interaction among the system components. Models include user-specified actuator, sensor, and control parameters, as well as kinematic and dynamic characteristics. Kinematic, dynamic, and response analyses can be selected, with system configuration, task trajectories, and arm states displayed using computer graphics. The second environment is a real-time, manned Telerobotic Systems Simulation (TRSS) which uses the facilities of the Intelligent Systems Research Laboratory (ISRL). It utilizes a hierarchical structure of functionally distributed computers communicating over both parallel and high-speed serial data paths to enable studies of advanced telerobotic systems. Multiple processes perform motion planning, operator communications, forward and inverse kinematics, control/sensor fusion, and I/O processing while communicating via common memory. Both ROBSIM and TRSS, including their capability, status, and future plans are discussed. Also described is the architecture of ISRL and recent telerobotic system studies in ISRL.

  7. The ISOPHOT Mapping Simulation System

    NASA Astrophysics Data System (ADS)

    Gabriel, C.; Hur, M.

    2002-12-01

    From version 9.0 onwards, the ISOPHOT Interactive Anal- ysis (PIA) package offers its users an integrated mapping simu- lation system, capable of generating sky images including sev- eral point / extended sources on a flat / gradient background, simulating what ISOPHOT would have recorded under certain instrument and spacecraft raster configurations. While the ben- efits of performing simulations for accessing the efficiency, ac- curacy, confusion level, etc., on different mapping algorithms and deconvolution techniques in and outside PIA are mostly of interest to calibrators and instrument specialists, it is also very important for a general observer because this highly user friendly system provides the possibility of simulating his / her observation by matching the selected observing mode.

  8. A Computational Workbench Environment For Virtual Power Plant Simulation

    SciTech Connect

    Bockelie, Michael J.; Swensen, David A.; Denison, Martin K.; Sarofim, Adel F.

    2001-11-06

    In this paper we describe our progress toward creating a computational workbench for performing virtual simulations of Vision 21 power plants. The workbench provides a framework for incorporating a full complement of models, ranging from simple heat/mass balance reactor models that run in minutes to detailed models that can require several hours to execute. The workbench is being developed using the SCIRun software system. To leverage a broad range of visualization tools the OpenDX visualization package has been interfaced to the workbench. In Year One our efforts have focused on developing a prototype workbench for a conventional pulverized coal fired power plant. The prototype workbench uses a CFD model for the radiant furnace box and reactor models for downstream equipment. In Year Two and Year Three, the focus of the project will be on creating models for gasifier based systems and implementing these models into an improved workbench. In this paper we describe our work effort for Year One and outline our plans for future work. We discuss the models included in the prototype workbench and the software design issues that have been addressed to incorporate such a diverse range of models into a single software environment. In addition, we highlight our plans for developing the energyplex based workbench that will be developed in Year Two and Year Three.

  9. Towards the Integration of APECS and VE-Suite for Virtual Power Plant Co-Simulation

    SciTech Connect

    Zitney, S.E.; McCorkle, D.; Yang, C.; Jordan, T.; Swensen, D.; Bryden, M.

    2007-05-01

    Process modeling and simulation tools are widely used for the design and operation of advanced power generation systems. These tools enable engineers to solve the critical process systems engineering problems that arise throughout the lifecycle of a power plant, such as designing a new process, troubleshooting a process unit or optimizing operations of the full process. To analyze the impact of complex thermal and fluid flow phenomena on overall power plant performance, the Department of Energy’s (DOE) National Energy Technology Laboratory (NETL) has developed the Advanced Process Engineering Co-Simulator (APECS). The APECS system is an integrated software suite that combines process simulation (e.g., Aspen Plus) and high-fidelity equipment simulations such as those based on computational fluid dynamics (CFD), together with advanced analysis capabilities including case studies, sensitivity analysis, stochastic simulation for risk/uncertainty analysis, and multi-objective optimization. In this paper we discuss the initial phases of the integration of the APECS system with the immersive and interactive virtual engineering software, VE-Suite, developed at Iowa State University and Ames Laboratory. VE-Suite uses the ActiveX (OLE Automation) controls in the Aspen Plus process simulator wrapped by the CASI library developed by Reaction Engineering International to run process/CFD co-simulations and query for results. This integration represents a necessary step in the development of virtual power plant co-simulations that will ultimately reduce the time, cost, and technical risk of developing advanced power generation systems.

  10. Collecting in Central Asia: National Plant Germplasm System Plant Explorations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA-ARS National Plant Germplasm System is charged with the preservation of economically important crop plants and their wild relatives. Curators in the System strive to develop collections capturing the genetic diversity of each species. One mechanism for filling gaps in collections is through...

  11. Aided targeting system simulation evaluation

    NASA Technical Reports Server (NTRS)

    Demaio, Joe; Becker, Curtis

    1994-01-01

    Simulation research was conducted at the Crew Station Research and Development Facility on the effectiveness and ease of use of three targeting systems. A manual system required the aviator to scan a target array area with a simulated second generation forward looking infrared (FLIR) sensor, locate and categorize targets, and construct a target hand-off list. The interface between the aviator and the system was like that of an advanced scout helicopter (manual mode). Two aided systems detected and categorized targets automatically. One system used only the FLIR sensor and the second used FLIR fused with Longbow radar. The interface for both was like that of an advanced scout helicopter aided mode. Exposure time while performing the task was reduced substantially with the aided systems, with no loss of target hand-off list accuracy. The fused sensor system showed lower time to construct the target hand-off list and a slightly lower false alarm rate than the other systems. A number of issues regarding system sensitivity and criterion, and operator interface design are discussed.

  12. Software Framework for Advanced Power Plant Simulations

    SciTech Connect

    John Widmann; Sorin Munteanu; Aseem Jain; Pankaj Gupta; Mark Moales; Erik Ferguson; Lewis Collins; David Sloan; Woodrow Fiveland; Yi-dong Lang; Larry Biegler; Michael Locke; Simon Lingard; Jay Yun

    2010-08-01

    This report summarizes the work accomplished during the Phase II development effort of the Advanced Process Engineering Co-Simulator (APECS). The objective of the project is to develop the tools to efficiently combine high-fidelity computational fluid dynamics (CFD) models with process modeling software. During the course of the project, a robust integration controller was developed that can be used in any CAPE-OPEN compliant process modeling environment. The controller mediates the exchange of information between the process modeling software and the CFD software. Several approaches to reducing the time disparity between CFD simulations and process modeling have been investigated and implemented. These include enabling the CFD models to be run on a remote cluster and enabling multiple CFD models to be run simultaneously. Furthermore, computationally fast reduced-order models (ROMs) have been developed that can be 'trained' using the results from CFD simulations and then used directly within flowsheets. Unit operation models (both CFD and ROMs) can be uploaded to a model database and shared between multiple users.

  13. Numerical Propulsion System Simulation Architecture

    NASA Technical Reports Server (NTRS)

    Naiman, Cynthia G.

    2004-01-01

    The Numerical Propulsion System Simulation (NPSS) is a framework for performing analysis of complex systems. Because the NPSS was developed using the object-oriented paradigm, the resulting architecture is an extensible and flexible framework that is currently being used by a diverse set of participants in government, academia, and the aerospace industry. NPSS is being used by over 15 different institutions to support rockets, hypersonics, power and propulsion, fuel cells, ground based power, and aerospace. Full system-level simulations as well as subsystems may be modeled using NPSS. The NPSS architecture enables the coupling of analyses at various levels of detail, which is called numerical zooming. The middleware used to enable zooming and distributed simulations is the Common Object Request Broker Architecture (CORBA). The NPSS Developer's Kit offers tools for the developer to generate CORBA-based components and wrap codes. The Developer's Kit enables distributed multi-fidelity and multi-discipline simulations, preserves proprietary and legacy codes, and facilitates addition of customized codes. The platforms supported are PC, Linux, HP, Sun, and SGI.

  14. An intelligent simulation training system

    NASA Technical Reports Server (NTRS)

    Biegel, John E.

    1990-01-01

    The Department of Industrial Engineering at the University of Central Florida, Embry-Riddle Aeronautical University and General Electric (SCSD) have been funded by the State of Florida to build an Intelligent Simulation Training System. The objective was and is to make the system generic except for the domain expertise. Researchers accomplished this objective in their prototype. The system is modularized and therefore it is easy to make any corrections, expansions or adaptations. The funding by the state of Florida has exceeded $3 million over the past three years and through the 1990 fiscal year. UCF has expended in excess of 15 work years on the project. The project effort has been broken into three major tasks. General Electric provides the simulation. Embry-Riddle Aeronautical University provides the domain expertise. The University of Central Florida has constructed the generic part of the system which is comprised of several modules that perform the tutoring, evaluation, communication, status, etc. The generic parts of the Intelligent Simulation Training Systems (ISTS) are described.

  15. Calculational limitations in PWR system simulation

    SciTech Connect

    Abramson, P.B.; Kennedy, M.F.; Speis, T.P.

    1982-01-01

    Engineering transient analysis codes, which are in general more accurate than the present generation of simulator software, can be expected to yield reasonably accurate results (+-20% or so on system pressure) if carefully utilized and if the two-phase and transient flow conditions are not severe. As the severity of the transient increases, the confidence that one may have in the results decreases. None of the existing engineering analysis codes is well assessed or verified for transient analysis, but all give qualitatively the same results lending credence to their results. Recent comparisons to transients in LOFT and SEMISCALE are encouraging as are various comparisons to actual plant data.

  16. Simulator verification techniques study. Integrated simulator self test system concepts

    NASA Technical Reports Server (NTRS)

    Montoya, G.; Wenglinski, T. H.

    1974-01-01

    Software and hardware requirements for implementing hardware self tests are presented in support of the development of training and procedures development simulators for the space shuttle program. Self test techniques for simulation hardware and the validation of simulation performance are stipulated. The requirements of an integrated simulator self system are analyzed. Readiness tests, fault isolation tests, and incipient fault detection tests are covered.

  17. Simulation and experimental research of 1MWe solar tower power plant in China

    NASA Astrophysics Data System (ADS)

    Yu, Qiang; Wang, Zhifeng; Xu, Ershu

    2016-05-01

    The establishment of a reliable simulation system for a solar tower power plant can greatly increase the economic and safety performance of the whole system. In this paper, a dynamic model of the 1MWe Solar Tower Power Plant at Badaling in Beijing is developed based on the "STAR-90" simulation platform, including the heliostat field, the central receiver system (water/steam), etc. The dynamic behavior of the global CSP plant can be simulated. In order to verify the validity of simulation system, a complete experimental process was synchronously simulated by repeating the same operating steps based on the simulation platform, including the locations and number of heliostats, the mass flow of the feed water, etc. According to the simulation and experimental results, some important parameters are taken out to make a deep comparison. The results show that there is good alignment between the simulations and the experimental results and that the error range can be acceptable considering the error of the models. In the end, a comprehensive and deep analysis on the error source is carried out according to the comparative results.

  18. Stochastic simulation in systems biology

    PubMed Central

    Székely, Tamás; Burrage, Kevin

    2014-01-01

    Natural systems are, almost by definition, heterogeneous: this can be either a boon or an obstacle to be overcome, depending on the situation. Traditionally, when constructing mathematical models of these systems, heterogeneity has typically been ignored, despite its critical role. However, in recent years, stochastic computational methods have become commonplace in science. They are able to appropriately account for heterogeneity; indeed, they are based around the premise that systems inherently contain at least one source of heterogeneity (namely, intrinsic heterogeneity). In this mini-review, we give a brief introduction to theoretical modelling and simulation in systems biology and discuss the three different sources of heterogeneity in natural systems. Our main topic is an overview of stochastic simulation methods in systems biology. There are many different types of stochastic methods. We focus on one group that has become especially popular in systems biology, biochemistry, chemistry and physics. These discrete-state stochastic methods do not follow individuals over time; rather they track only total populations. They also assume that the volume of interest is spatially homogeneous. We give an overview of these methods, with a discussion of the advantages and disadvantages of each, and suggest when each is more appropriate to use. We also include references to software implementations of them, so that beginners can quickly start using stochastic methods for practical problems of interest. PMID:25505503

  19. Gasification CFD Modeling for Advanced Power Plant Simulations

    SciTech Connect

    Zitney, S.E.; Guenther, C.P.

    2005-09-01

    In this paper we have described recent progress on developing CFD models for two commercial-scale gasifiers, including a two-stage, coal slurry-fed, oxygen-blown, pressurized, entrained-flow gasifier and a scaled-up design of the PSDF transport gasifier. Also highlighted was NETL’s Advanced Process Engineering Co-Simulator for coupling high-fidelity equipment models with process simulation for the design, analysis, and optimization of advanced power plants. Using APECS, we have coupled the entrained-flow gasifier CFD model into a coal-fired, gasification-based FutureGen power and hydrogen production plant. The results for the FutureGen co-simulation illustrate how the APECS technology can help engineers better understand and optimize gasifier fluid dynamics and related phenomena that impact overall power plant performance.

  20. Modeling, simulation, and control of an extraterrestrial oxygen production plant

    NASA Technical Reports Server (NTRS)

    Schooley, L.; Cellier, F.; Zeigler, B.; Doser, A.; Farrenkopf, G.

    1991-01-01

    The immediate objective is the development of a new methodology for simulation of process plants used to produce oxygen and/or other useful materials from local planetary resources. Computer communication, artificial intelligence, smart sensors, and distributed control algorithms are being developed and implemented so that the simulation or an actual plant can be controlled from a remote location. The ultimate result of this research will provide the capability for teleoperation of such process plants which may be located on Mars, Luna, an asteroid, or other objects in space. A very useful near-term result will be the creation of an interactive design tool, which can be used to create and optimize the process/plant design and the control strategy. This will also provide a vivid, graphic demonstration mechanism to convey the results of other researchers to the sponsor.

  1. New data on the effects of simulated microgravity on viral infection development in wheat plants

    NASA Astrophysics Data System (ADS)

    Mishchenko, Lidiya

    The aim of research was to identify the effects of simulated microgravity on plant relations with the most widespread and damageful viruses of important agricultural crops, particularly wheat with wheat streak mosaic virus (WSMV). The experiments were carried out in autumn of 2007. The object of research were spring wheat plants of the Apogee variety (third reproduction) grown by us under clinorotation in 2002 - 2003 and multiplied in 2005 in the hothouse of the biological faculty of Kyiv National Taras Shevchenko University and the wheat streak mosaic virus. Microgravity was simulated using KG - 8 and "Cycle- 2" clinostats with horizontal and vertical clinorotation (HC and VC). In the first variant the axis of plant growth is placed horizontally and coincides with the axis of container rotation; in the second variant the axis is placed vertically and perpendicular to the axis of rotation. Virus identification in plants and quantitative determination of antigens were carried out using ELISA procedure and electron microscopy. Under the action of simulated microgravity, in KG -8 the lowering of height of infected plants as compared with healthy did not exceed this parameter in plants grown in motionless containers, as the percent of lowering in both variants with WSMV infection was the same - about 15 It was detected, that "WSMV - host plant" system was endowed with a certain gravisensitivity, and the action of simulated microgravity on this system was connected with the formation of reactions in host plant, which limit the reproduction of viruses in the cells. Longterm influence of simulated microgravity lowered the activity of viral pathogens in the system "virus - host" even in the third reproduction. Te influence of simulated microgravity caused the stress in wheat plants but its intensity was not threshold and plants could adapt themselves to the action of stress agent. This proves the possibility of the growth and development of plants under conditions of

  2. Using cellzilla for plant growth simulations at the cellular level

    PubMed Central

    Shapiro, Bruce E.; Meyerowitz, Elliot M.; Mjolsness, Eric

    2013-01-01

    Cellzilla is a two-dimensional tissue simulation platform for plant modeling utilizing Cellerator arrows. Cellerator describes biochemical interactions with a simplified arrow-based notation; all interactions are input as reactions and are automatically translated to the appropriate differential equations using a computer algebra system. Cells are represented by a polygonal mesh of well-mixed compartments. Cell constituents can interact intercellularly via Cellerator reactions utilizing diffusion, transport, and action at a distance, as well as amongst themselves within a cell. The mesh data structure consists of vertices, edges (vertex pairs), and cells (and optional intercellular wall compartments) as ordered collections of edges. Simulations may be either static, in which cell constituents change with time but cell size and shape remain fixed; or dynamic, where cells can also grow. Growth is controlled by Hookean springs associated with each mesh edge and an outward pointing pressure force. Spring rest length grows at a rate proportional to the extension beyond equilibrium. Cell division occurs when a specified constituent (or cell mass) passes a (random, normally distributed) threshold. The orientation of new cell walls is determined either by Errera's rule, or by a potential model that weighs contributions due to equalizing daughter areas, minimizing wall length, alignment perpendicular to cell extension, and alignment perpendicular to actual growth direction. PMID:24137172

  3. Propulsion System Modeling and Simulation

    NASA Technical Reports Server (NTRS)

    Tai, Jimmy C. M.; McClure, Erin K.; Mavris, Dimitri N.; Burg, Cecile

    2002-01-01

    The Aerospace Systems Design Laboratory at the School of Aerospace Engineering in Georgia Institute of Technology has developed a core competency that enables propulsion technology managers to make technology investment decisions substantiated by propulsion and airframe technology system studies. This method assists the designer/manager in selecting appropriate technology concepts while accounting for the presence of risk and uncertainty as well as interactions between disciplines. This capability is incorporated into a single design simulation system that is described in this paper. This propulsion system design environment is created with a commercially available software called iSIGHT, which is a generic computational framework, and with analysis programs for engine cycle, engine flowpath, mission, and economic analyses. iSIGHT is used to integrate these analysis tools within a single computer platform and facilitate information transfer amongst the various codes. The resulting modeling and simulation (M&S) environment in conjunction with the response surface method provides the designer/decision-maker an analytical means to examine the entire design space from either a subsystem and/or system perspective. The results of this paper will enable managers to analytically play what-if games to gain insight in to the benefits (and/or degradation) of changing engine cycle design parameters. Furthermore, the propulsion design space will be explored probabilistically to show the feasibility and viability of the propulsion system integrated with a vehicle.

  4. Simulation: A tool for steam plant dynamic analysis

    NASA Astrophysics Data System (ADS)

    Anneveld, H.

    Stringent requirements of combined cycles makes design and operation of process plants increasingly complex. The behavior of the complete controlled process is studied by way of simulation. By utilizing this method, process conditions can be optimized with reduced risk. This will lead to greater financial benefits. There is a large range of simulation programs which make it possible to study realistically the dynamic behavior of a wide range of complex process conditions and problematic interactions. The steam generation and distribution, the pressure limitation controls, and the dynamic behavior of a steam plant are discussed.

  5. MERTIS: system theory and simulation

    NASA Astrophysics Data System (ADS)

    Paproth, Carsten; Säuberlich, Thomas; Jahn, Herbert; Helbert, Jörn

    2010-09-01

    The deep-space ESA mission BepiColombo to planet Mercury will contain the advanced infrared remote sensing instrument MERTIS (MErcury Radiometer and Thermal infrared Imaging Spectrometer). The mission has the goal to explore the planets inner and surface structure and its environment. With MERTIS investigations of Mercury's surface layer within a spectral range of 7-14μm shall be conducted to specify and map Mercury's mineralogical composition with a spatial resolution of 500m. Due to the limited mass and power budget the used micro-bolometer detector array will only have a temperature-stabilization and will not be cooled. The theoretical description of the instrument is necessary to estimate the performance of the instrument especially the signal to noise ratio. For that purpose theoretical models are derived from system theory. For a better evaluation and understanding of the instrument performance simulations are performed to compute the passage of the radiation of a hypothetical mineralogical surface composition through the optical system, the influence of the inner instrument radiation and the conversion of the overall radiation into a detector voltage and digital output signal. The results of the simulation can support the optimization process of the instrument parameters and could also assist the analysis of gathered scientific data. The simulation tool can be used as well for performance estimations of MERTIS-like systems for future projects.

  6. A Nonlinear Propulsion System Simulation Technique for Piloted Simulators

    NASA Technical Reports Server (NTRS)

    Mihaloew, J. R.

    1981-01-01

    In the past, propulsion system simulations used in flight simulators have been extremely simple. This resulted in a loss of simulation realism since significant engine and aircraft interactions were neglected and important internal engine parameters were not computed. More detailed propulsion system simulators are needed to permit evaluations of modern aircraft propulsion systems in a simulated flight environment. A real time digital simulation technique has been developed which provides the capabilities needed to evaluate propulsion system performance and aircraft system interaction on manned flight simulators. A parameter correlation technique is used with real and pseudo dynamics in a stable integration convergence loop. The technique has been applied to a multivariable propulsion system for use in a piloted NASA flight simulator program. Cycle time is 2.0 ms on a Univac 1110 computer and 5.7 ms on the simulator computer, a Xerox Sigma 8. The model is stable and accurate with time steps up to 50 ms. The program evaluated the simulation technique and the propulsion system digital control. The simulation technique and model used in that program are described and results from the simulation are presented.

  7. Building simulation models of developing plant organs using VirtualLeaf.

    PubMed

    Merks, Roeland M H; Guravage, Michael A

    2013-01-01

    Cell-based computational modeling and simulation are becoming invaluable tools in analyzing plant -development. In a cell-based simulation model, the inputs are behaviors and dynamics of individual cells and the rules describe responses to signals from adjacent cells. The outputs are the growing tissues, shapes and cell-differentiation patterns that emerge from the local, chemical and biomechanical cell-cell interactions. Here, we present a step-by-step, practical tutorial for building cell-based simulations of plant development with VirtualLeaf, a freely available, open-source software framework for modeling plant development. We show how to build a model of a growing tissue, a reaction-diffusion system on a growing domain, and an auxin transport model. The aim of VirtualLeaf is to make computational modeling better accessible to experimental plant biologists with relatively little computational background. PMID:23299687

  8. Simulation-based disassembly systems design

    NASA Astrophysics Data System (ADS)

    Ohlendorf, Martin; Herrmann, Christoph; Hesselbach, Juergen

    2004-02-01

    Recycling of Waste of Electrical and Electronic Equipment (WEEE) is a matter of actual concern, driven by economic, ecological and legislative reasons. Here, disassembly as the first step of the treatment process plays a key role. To achieve sustainable progress in WEEE disassembly, the key is not to limit analysis and planning to merely disassembly processes in a narrow sense, but to consider entire disassembly plants including additional aspects such as internal logistics, storage, sorting etc. as well. In this regard, the paper presents ways of designing, dimensioning, structuring and modeling different disassembly systems. Goal is to achieve efficient and economic disassembly systems that allow recycling processes complying with legal requirements. Moreover, advantages of applying simulation software tools that are widespread and successfully utilized in conventional industry sectors are addressed. They support systematic disassembly planning by means of simulation experiments including consecutive efficiency evaluation. Consequently, anticipatory recycling planning considering various scenarios is enabled and decisions about which types of disassembly systems evidence appropriateness for specific circumstances such as product spectrum, throughput, disassembly depth etc. is supported. Furthermore, integration of simulation based disassembly planning in a holistic concept with configuration of interfaces and data utilization including cost aspects is described.

  9. Simulation and optimization of an experimental membrane wastewater treatment plant using computational intelligence methods.

    PubMed

    Ludwig, T; Kern, P; Bongards, M; Wolf, C

    2011-01-01

    The optimization of relaxation and filtration times of submerged microfiltration flat modules in membrane bioreactors used for municipal wastewater treatment is essential for efficient plant operation. However, the optimization and control of such plants and their filtration processes is a challenging problem due to the underlying highly nonlinear and complex processes. This paper presents the use of genetic algorithms for this optimization problem in conjunction with a fully calibrated simulation model, as computational intelligence methods are perfectly suited to the nonconvex multi-objective nature of the optimization problems posed by these complex systems. The simulation model is developed and calibrated using membrane modules from the wastewater simulation software GPS-X based on the Activated Sludge Model No.1 (ASM1). Simulation results have been validated at a technical reference plant. They clearly show that filtration process costs for cleaning and energy can be reduced significantly by intelligent process optimization. PMID:21977647

  10. Plant health sensing system for determining nitrogen status in plants

    NASA Astrophysics Data System (ADS)

    Thomasson, J. A.; Sui, Ruixiu; Read, John J.; Reddy, K. R.

    2004-03-01

    A plant health sensing system was developed for determining nitrogen status in plants. The system consists of a multi-spectral optical sensor and a data-acquisition and processing unit. The optical sensor"s light source provides modulated panchromatic illumination of a plant canopy with light-emitting diodes, and the sensor measures spectral reflectance through optical filters that partition the energy into blue, green, red, and near-infrared wavebands. Spectral reflectance of plants is detected in situ, at the four wavebands, in real time. The data-acquisition and processing unit is based on a single board computer that collects data from the multi-spectral sensor and spatial information from a global positioning system receiver. Spectral reflectance at the selected wavebands is analyzed, with algorithms developed during preliminary work, to determine nitrogen status in plants. The plant health sensing system has been tested primarily in the laboratory and field so far, and promising results have been obtained. This article describes the development, theory of operation, and test results of the plant health sensing system.

  11. AVPROG. MC Simulation of System Availability

    SciTech Connect

    McGrady, P.W.; Reynolds, L.D.

    1985-07-25

    AVPROG is a large-scale simulation program used to estimate steady-state availability of a system, typically a large production unit. The system is modeled as a success logic flow block diagram of equipment affecting the production output. AVPROG simulates system operation over a specified time period using Monte Carlo techniques. System components are failed and restarted using numerous types of distributions that are available. Among the distributions available are the exponential and the lognormal. AVPROG computes availability based on averages from a number of simulation cases (batches) for the specified production time interval. It also ranks unavailability contributors to permit investigation of design modifications that have the greatest impact on availability. Input to AVPROG consists of system geometry (as defined on logic diagrams), mean time between failures (MTBF), mean time to restore (MTTR), and mean plant delta (MPD) for each logic block. MTTR is defined to include access time, equipment preparation time, actual replace time, cleanup time, and time to restore the equipment and associated subsystem to normal operation. MPD is defined as additional time to restore full production after the equipment in the logic block has been restored. AVPROG is unique in its ability to handle MPD in a parallel logic configuration. AVPROG can handle K-out-of-N parallel configurations where the components are not identical. It can also handle weighted and normalized parallel configurations. In considering parallel configurations in the logic diagram, all components are assumed to be operating normally and not on standby. The output shows not only the system availability, but also the contribution of each block to system unavailability, ranked in order of size of the contribution.

  12. Simulation of linear mechanical systems

    NASA Technical Reports Server (NTRS)

    Sirlin, S. W.

    1993-01-01

    A dynamics and controls analyst is typically presented with a structural dynamics model and must perform various input/output tests and design control laws. The required time/frequency simulations need to be done many times as models change and control designs evolve. This paper examines some simple ways that open and closed loop frequency and time domain simulations can be done using the special structure of the system equations usually available. Routines were developed to run under Pro-Matlab in a mixture of the Pro-Matlab interpreter and FORTRAN (using the .mex facility). These routines are often orders of magnitude faster than trying the typical 'brute force' approach of using built-in Pro-Matlab routines such as bode. This makes the analyst's job easier since not only does an individual run take less time, but much larger models can be attacked, often allowing the whole model reduction step to be eliminated.

  13. The application of simulation modeling to the cost and performance ranking of solar thermal power plants

    NASA Technical Reports Server (NTRS)

    Rosenberg, L. S.; Revere, W. R.; Selcuk, M. K.

    1981-01-01

    A computer simulation code was employed to evaluate several generic types of solar power systems (up to 10 MWe). Details of the simulation methodology, and the solar plant concepts are given along with cost and performance results. The Solar Energy Simulation computer code (SESII) was used, which optimizes the size of the collector field and energy storage subsystem for given engine-generator and energy-transport characteristics. Nine plant types were examined which employed combinations of different technology options, such as: distributed or central receivers with one- or two-axis tracking or no tracking; point- or line-focusing concentrator; central or distributed power conversion; Rankin, Brayton, or Stirling thermodynamic cycles; and thermal or electrical storage. Optimal cost curves were plotted as a function of levelized busbar energy cost and annualized plant capacity. Point-focusing distributed receiver systems were found to be most efficient (17-26 percent).

  14. Modeling of an industrial alcohol fermentation and simulation of the plant by a process simulator

    SciTech Connect

    Pascal, F.; Corriou, J.P.; Pons, M.N.; Dagot, C.; Engasser, J.M.; Pingaud, H.

    1995-05-05

    The aim of the present study was the development of a general simulation module for fermentation within the framework of existing chemical process simulators. This module has been applied to an industrial plant which produces ethanol from beet molasses and fresh beet juice by Saccharomyces cerevisiae. An unstructured mechanistic model has been developed with kinetic laws that are based on a chemically defined reaction scheme which satisfies stoichiometric constraints. This model can be applied to different culture conditions and takes into account secondary byproducts such as higher alcohols. These byproducts are of prime importance and need to be correctly estimated because a sequence of distillation columns follow the fermentor in the plant. Important measurement campaigns have been performed on the plant to validate the model. Plant operation has been successfully simulated using the same kinetic model for both continuous and fed-batch modes of production.

  15. OXYGEN UTILIZATION IN ACTIVATED SLUDGE PLANTS: SIMULATION AND MODEL CALIBRATION

    EPA Science Inventory

    The objective of the research described in the report is to apply recent advances in activated sludge process modeling to the simulation of oxygen utilization rates in full scale activated sludge treatment plants. This is accomplished by calibrating the International Association ...

  16. Plant morphological characteristics and resistance to simulated trampling

    NASA Astrophysics Data System (ADS)

    Sun, Dan; Liddle, Michael J.

    1993-07-01

    The relationship between responses of plants to trampling and their morphological characteristics was studied in a glasshouse experiment. Thirteen species with four different growth forms were used in this experiment. They were five tussock species. Chloris gayana, Eragrostis tenuifolia, Lolium perenne, Panicum maximum, and Sporobolus elongatus; three prostate grasses, Axonopus compressus, Cynodon dactylon, and Trifolium repens, two herbaceous species, Daucus glochidiatus and Hypochoeris radicata; and three woody species, Acacia macradenia, Acrotriche aggregata, and Sida rhombifolia. These species were subjected to three levels of simulated trampling. For each species, measurements were taken of aboveground biomass, root biomass, leaf length, leaf width, leaf thickness, leaf number, broken leaf number and plant height. Overall, these measurements were greatest in the control plants, moderate in the level of light trampling, and the lowest in the level of heavy trampling. Biomass was used as a basis of the assessment of plant resistance to trampling. Three tussock species, Eragrostis tenuifolia, Lolium perenne, and Sporobolus elongatus had a high resistance. Woody and erect herbaceous plants were more intolerant to trampling. There appear to be two processes involved in the reduction of the plant parameters: direct physical damage with portions of the plants detached, and physiological changes, which slow down vegetative growth rates. Plant height was found to be the most sensitive indicator of trampling damage.

  17. Dynamics of a plant-herbivore-predator system with plant-toxicity

    USGS Publications Warehouse

    Feng, Zhilan; Qiu, Zhipeng; Liu, Rongsong; DeAngelis, Donald L.

    2011-01-01

    A system of ordinary differential equations is considered that models the interactions of two plant species populations, an herbivore population, and a predator population. We use a toxin-determined functional response to describe the interactions between plant species and herbivores and use a Holling Type II functional response to model the interactions between herbivores and predators. In order to study how the predators impact the succession of vegetation, we derive invasion conditions under which a plant species can invade into an environment in which another plant species is co-existing with a herbivore population with or without a predator population. These conditions provide threshold quantities for several parameters that may play a key role in the dynamics of the system. Numerical simulations are conducted to reinforce the analytical results. This model can be applied to a boreal ecosystem trophic chain to examine the possible cascading effects of predator-control actions when plant species differ in their levels of toxic defense.

  18. Requirements for advanced simulation of nuclear reactor and chemicalseparation plants.

    SciTech Connect

    Palmiotti, G.; Cahalan, J.; Pfeiffer, P.; Sofu, T.; Taiwo, T.; Wei,T.; Yacout, A.; Yang, W.; Siegel, A.; Insepov, Z.; Anitescu, M.; Hovland,P.; Pereira, C.; Regalbuto, M.; Copple, J.; Willamson, M.

    2006-12-11

    This report presents requirements for advanced simulation of nuclear reactor and chemical processing plants that are of interest to the Global Nuclear Energy Partnership (GNEP) initiative. Justification for advanced simulation and some examples of grand challenges that will benefit from it are provided. An integrated software tool that has its main components, whenever possible based on first principles, is proposed as possible future approach for dealing with the complex problems linked to the simulation of nuclear reactor and chemical processing plants. The main benefits that are associated with a better integrated simulation have been identified as: a reduction of design margins, a decrease of the number of experiments in support of the design process, a shortening of the developmental design cycle, and a better understanding of the physical phenomena and the related underlying fundamental processes. For each component of the proposed integrated software tool, background information, functional requirements, current tools and approach, and proposed future approaches have been provided. Whenever possible, current uncertainties have been quoted and existing limitations have been presented. Desired target accuracies with associated benefits to the different aspects of the nuclear reactor and chemical processing plants were also given. In many cases the possible gains associated with a better simulation have been identified, quantified, and translated into economical benefits.

  19. Accuracy analysis of distributed simulation systems

    NASA Astrophysics Data System (ADS)

    Lin, Qi; Guo, Jing

    2010-08-01

    Existed simulation works always emphasize on procedural verification, which put too much focus on the simulation models instead of simulation itself. As a result, researches on improving simulation accuracy are always limited in individual aspects. As accuracy is the key in simulation credibility assessment and fidelity study, it is important to give an all-round discussion of the accuracy of distributed simulation systems themselves. First, the major elements of distributed simulation systems are summarized, which can be used as the specific basis of definition, classification and description of accuracy of distributed simulation systems. In Part 2, the framework of accuracy of distributed simulation systems is presented in a comprehensive way, which makes it more sensible to analyze and assess the uncertainty of distributed simulation systems. The concept of accuracy of distributed simulation systems is divided into 4 other factors and analyzed respectively further more in Part 3. In Part 4, based on the formalized description of framework of accuracy analysis in distributed simulation systems, the practical approach are put forward, which can be applied to study unexpected or inaccurate simulation results. Following this, a real distributed simulation system based on HLA is taken as an example to verify the usefulness of the approach proposed. The results show that the method works well and is applicable in accuracy analysis of distributed simulation systems.

  20. Simulated climate-vegetation interaction in semi-arid regions affected by plant diversity

    NASA Astrophysics Data System (ADS)

    Claussen, M.; Bathiany, S.; Brovkin, V.; Kleinen, T.

    2013-11-01

    The end of the African Humid Period between 6,000 and 4,000 years ago was associated with large changes in precipitation and vegetation cover. Sediment records from Lake Yoa, Chad, show a gradual decline in precipitation and fluctuation in vegetation over this interval, and have been suggested to demonstrate a weak interaction between climate and vegetation. However, interpretation of these data has neglected the potential effects of plant diversity on the stability of the climate-vegetation system. Here we use a conceptual model that represents plant diversity in terms of moisture requirement. Some of the plant types simulated are sensitive to changes in precipitation, which alone would lead to an unstable system with the possibility of abrupt changes. Other plants are more resilient, resulting in a stable system that changes gradually. We demonstrate that plant diversity tends to attenuate the instability of the interaction between climate and sensitive plant types, whereas it reduces the stability of the interaction between climate and less-sensitive plant types. Hence, despite large sensitivities of individual plant types to precipitation, a gradual decline in precipitation and shift in mean vegetation cover can occur. However, we suggest that the system could become unstable if some plant types were removed or introduced, leading to an abrupt regime shift.

  1. 3D simulation of plant and living tissue superficial lesions

    NASA Astrophysics Data System (ADS)

    Bratchenko, Ivan A.; Sindyaeva, Alexandra R.; Zakharov, Valery P.

    2008-06-01

    The analytic schemes of calculated absorbed and scattered radiation spatial distribution in multilayer plant and living tissues and diagnostic of their physical state are presented. The correct realization of these tasks was obtained with 3D Monte Carlo simulation of optical radiation propagation through multiple scattering medium in TracePro environment. Analysis of simulation data was made by differential backscattering method, which allows to investigate general backscattered radiation dependences on optical and geometrical parameters of living tissue. It was shown that obtained results formed the basis for developing an algorithm of optical superficial inhomogeneous registration and spatial localization. Such diagnosis can be executed in tissues of any arbitrary surface structure. Designed scheme is intended to utilize in contactless macro diagnostics device. The same approach was used for simulation of optical spectra of healthy and diseased virtual leaves for plant tissue pathological changes revealing.

  2. Design of virtual SCADA simulation system for pressurized water reactor

    NASA Astrophysics Data System (ADS)

    Wijaksono, Umar; Abdullah, Ade Gafar; Hakim, Dadang Lukman

    2016-02-01

    The Virtual SCADA system is a software-based Human-Machine Interface that can visualize the process of a plant. This paper described the results of the virtual SCADA system design that aims to recognize the principle of the Nuclear Power Plant type Pressurized Water Reactor. This simulation uses technical data of the Nuclear Power Plant Unit Olkiluoto 3 in Finland. This device was developed using Wonderware Intouch, which is equipped with manual books for each component, animation links, alarm systems, real time and historical trending, and security system. The results showed that in general this device can demonstrate clearly the principles of energy flow and energy conversion processes in Pressurized Water Reactors. This virtual SCADA simulation system can be used as instructional media to recognize the principle of Pressurized Water Reactor.

  3. Power plant entrainment simulation utilizing a condenser tube simulator. Final report 1 Dec 77-29 May 81

    SciTech Connect

    Poje, G.V.; Riordan, S.A.; O'Connor, J.M.

    1981-09-01

    The impact of entrainment within a power plant condenser tube was examined with a multipurpose simulation device. The lethal and sublethal effects of the three most important stressors were examined. Thermal stress was applied along the length of the condenser tube as is the case in power plants and exposures typical of power plants were recreated. Chlorine biocide was applied to the system prior to condenser transit. Fluid/mechanical stresses such as velocity shear, mechanical buffeting and hydrostatic pressure change were simulated to approximate entrainment events. The lethal and sublethal responses to condenser tube passage of six representative important species are presented in detail; these include the early life history stages of striped bass (Morone saxatilis) and carp (Cyprinus carpio) and various macrozooplankton.

  4. Reactor Subsystem Simulation for Nuclear Hybrid Energy Systems

    SciTech Connect

    Shannon Bragg-Sitton; J. Michael Doster; Alan Rominger

    2012-09-01

    Preliminary system models have been developed by Idaho National Laboratory researchers and are currently being enhanced to assess integrated system performance given multiple sources (e.g., nuclear + wind) and multiple applications (i.e., electricity + process heat). Initial efforts to integrate a Fortran-based simulation of a small modular reactor (SMR) with the balance of plant model have been completed in FY12. This initial effort takes advantage of an existing SMR model developed at North Carolina State University to provide initial integrated system simulation for a relatively low cost. The SMR subsystem simulation details are discussed in this report.

  5. The SAM software system for modeling severe accidents at nuclear power plants equipped with VVER reactors on full-scale and analytic training simulators

    NASA Astrophysics Data System (ADS)

    Osadchaya, D. Yu.; Fuks, R. L.

    2014-04-01

    The architecture of the SAM software package intended for modeling beyond-design-basis accidents at nuclear power plants equipped with VVER reactors evolving into a severe stage with core melting and failure of the reactor pressure vessel is presented. By using the SAM software package it is possible to perform comprehensive modeling of the entire emergency process from the failure initiating event to the stage of severe accident involving meltdown of nuclear fuel, failure of the reactor pressure vessel, and escape of corium onto the concrete basement or into the corium catcher with retention of molten products in it.

  6. Efficient solution techniques for simulation nutrient uptake by plant roots

    NASA Astrophysics Data System (ADS)

    Abesha, Betiglu; Vanderborght, Jan; Javaux, Mathieu; Schnepf, Andrea; Vereecken, Harry

    2015-04-01

    Water and nutrient transfer to plant roots is determined by processes occurring from the single root to the entire root system. A mechanistic spatially distributed description of these processes would require a sub mm discretization which is computationally not feasible. In this contribution, we present efficient solution techniques to represent accurate nutrient uptake by plant roots. The first solution technique describes nutrient transport towards a single root segment using a 1-D radially axisymmetric model (Barber and Cushman 1981). Transport to the entire root system is represented by a network of connected cylindrical models around the roots. This network of cylinders was coupled to a 3-D regular grid that was used to solve the flow and transport equations in the soil at the root system scale (Javaux et al. 2008). The second technique was a modified time compression approximation (TCA), which can be a simple and reasonably accurate semi-analytical method for predicting cumulative nutrient uptake when the convection flux and diffusion coefficient change over time due to for instance soil drying. The analytical approach presented by Roose et al. (2001) to calculate solute cumulative uptake provides means to analyze cumulative nutrient uptake at a changing diffusive-convective flux over time but with constant convection and diffusion coefficient. This analytical solution was used in TCA framework to predict uptake when convection and diffusion coefficient change over time. We compared cumulative nutrient uptake by the 1D / 3D coupled model with results obtained by spatially highly resolved 3-D model and the approximate analytical solution of Roose et al. (2001). The good agreement between both model approaches allows the use of the 1D/3D coupling approach to simulate water and nutrient transport at the a root system scale with minimal computational cost and good accuracy. This approach also accounts for the effect of transpiration and soil drying on nutrient

  7. Simulation System Fidelity Assessment at the Vertical Motion Simulator

    NASA Technical Reports Server (NTRS)

    Beard, Steven D.; Reardon, Scott E.; Tobias, Eric L.; Aponso, Bimal L.

    2013-01-01

    Fidelity is a word that is often used but rarely understood when talking about groundbased simulation. Assessing the cueing fidelity of a ground based flight simulator requires a comparison to actual flight data either directly or indirectly. Two experiments were conducted at the Vertical Motion Simulator using the GenHel UH-60A Black Hawk helicopter math model that was directly compared to flight data. Prior to the experiment the simulator s motion and visual system frequency responses were measured, the aircraft math model was adjusted to account for the simulator motion system delays, and the motion system gains and washouts were tuned for the individual tasks. The tuned motion system fidelity was then assessed against the modified Sinacori criteria. The first experiments showed similar handling qualities ratings (HQRs) to actual flight for a bob-up and sidestep maneuvers. The second experiment showed equivalent HQRs between flight and simulation for the ADS33 slalom maneuver for the two pilot participants. The ADS33 vertical maneuver HQRs were mixed with one pilot rating the flight and simulation the same while the second pilot rated the simulation worse. In addition to recording HQRs on the second experiment, an experimental Simulation Fidelity Rating (SFR) scale developed by the University of Liverpool was tested for applicability to engineering simulators. A discussion of the SFR scale for use on the Vertical Motion Simulator is included in this paper.

  8. A model framework to represent plant-physiology and rhizosphere processes in soil profile simulation models

    NASA Astrophysics Data System (ADS)

    Vanderborght, J.; Javaux, M.; Couvreur, V.; Schröder, N.; Huber, K.; Abesha, B.; Schnepf, A.; Vereecken, H.

    2013-12-01

    Plant roots play a crucial role in several key processes in soils. Besides their impact on biogeochemical cycles and processes, they also have an important influence on physical processes such as water flow and transport of dissolved substances in soils. Interaction between plant roots and soil processes takes place at different scales and ranges from the scale of an individual root and its directly surrounding soil or rhizosphere over the scale of a root system of an individual plant in a soil profile to the scale of vegetation patterns in landscapes. Simulation models that are used to predict water flow and solute transport in soil-plant systems mainly focus on the individual plant root system scale, parameterize single-root scale phenomena, and aggregate the root system scale to the vegetation scale. In this presentation, we will focus on the transition from the single root to the root system scale. Using high resolution non-invasive imaging techniques and methods, gradients in soil properties and states around roots and their difference from the bulk soil properties could be demonstrated. Recent developments in plant sciences provide new insights in the mechanisms that control water fluxes in plants and in the adaptation of root properties or root plasticity to changing soil conditions. However, since currently used approaches to simulate root water uptake neither resolve these small scale processes nor represent processes and controls within the root system, transferring this information to the whole soil-plant system scale is a challenge. Using a simulation model that describes flow and transport processes in the soil, resolves flow and transport towards individual roots, and describes flow and transport within the root system, such a transfer could be achieved. We present a few examples that illustrate: (i) the impact of changed rhizosphere hydraulic properties, (ii) the effect of root hydraulic properties and root system architecture, (iii) the regulation

  9. Root Zone Respiration on Hydroponically Grown Wheat Plant Systems

    NASA Technical Reports Server (NTRS)

    Soler-Crespo, R. A.; Monje, O. A.

    2010-01-01

    Root respiration is a biological phenomenon that controls plant growth and physiological development during a plant's lifespan. This process is dependent on the availability of oxygen in the system where the plant is located. In hydroponic systems, where plants are submerged in a solution containing vital nutrients but no type of soil, the availability of oxygen arises from the dissolved oxygen concentration in the solution. This oxygen concentration is dependent on the , gas-liquid interface formed on the upper surface of the liquid, as given by Henry's Law, depending on pressure and temperature conditions. Respiration rates of the plants rise as biomass and root zone increase with age. The respiration rate of Apogee wheat plants (Triticum aestivum) was measured as a function of light intensity (catalytic for photosynthesis) and CO2 concentration to determine their effect on respiration rates. To determine their effects on respiration rate and plant growth microbial communities were introduced into the system, by Innoculum. Surfactants were introduced, simulating gray-water usage in space, as another factor to determine their effect on chemical oxygen demand of microbials and on respiration rates of the plants. It is expected to see small effects from changes in CO2 concentration or light levels, and to see root respiration decrease in an exponential manner with plant age and microbial activity.

  10. Electrical aspects of photovoltaic-system simulation

    NASA Astrophysics Data System (ADS)

    Hart, G. W.; Raghuraman, P.

    1982-06-01

    A TRNSYS simulation was developed to simulate the performance of utility interactive residential photovoltaic energy systems. The PV system is divided into major functional components, which are individually described with computer models. The results of simulation and actual measured data are compared. The electrical influences on the design of such photovoltaic energy systems are given particular attention.

  11. AVESTAR Center: Dynamic simulation-based collaboration toward achieving opertional excellence for IGCC plants with crbon capture

    SciTech Connect

    Zitney, Strphen E.; Liese, Eric A.; Mahapatra, Priyadarshi; Turton, Richard; Bhattacharyya, Debangsu; Provost, Graham

    2012-01-01

    To address challenges in attaining operational excellence for clean energy plants, the National Energy Technology Laboratory has launched a world-class facility for Advanced Virtual Energy Simulation Training And Research (AVESTAR(TM)). The AVESTAR Center brings together state-of-the-art, real-time, high-fidelity dynamic simulators with operator training systems and 3D virtual immersive training systems into an integrated energy plant and control room environment. This paper will highlight the AVESTAR Center simulators, facilities, and comprehensive training, education, and research programs focused on the operation and control of an integrated gasification combined cycle power plant (IGCC) with carbon dioxide capture.

  12. Simulation of centrifugal compressor transient performance for process plant applications

    SciTech Connect

    MacDougal, I.; Elder, R.L.

    1983-01-01

    The development of a theoretical model capable of simulating centrifugal compressor transient performance (including compressor surge) is detailed. Simulation results from a Fortran computer program are compared with measured compressor transient data. Good simulation of compressor transients between stable operating points, and compressor presurge flow oscillations has been obtained. General application criteria are presented for the geometric distribution of model elements within a compressor system. Model applications and future work are outlined.

  13. Generalized Fluid System Simulation Program

    NASA Technical Reports Server (NTRS)

    Majumdar, Alok Kumar (Inventor); Bailey, John W. (Inventor); Schallhorn, Paul Alan (Inventor); Steadman, Todd E. (Inventor)

    2004-01-01

    A general purpose program implemented on a computer analyzes steady state and transient flow in a complex fluid network, modeling phase changes, compressibility, mixture thermodynamics and external body forces such as gravity and centrifugal force. A preprocessor provides for the inter- active development of a fluid network simulation having nodes and branches. Mass, energy, and specie conservation equations are solved at the nodes, and momentum conservation equations are solved in the branches. Contained herein are subroutines for computing "real fluid" thermodynamic and thermophysical properties for 12 fluids, and a number of different source options are provided for model- ing momentum sources or sinks in the branches. The system of equations describing the fluid network is solved by a hybrid numerical method that is a combination of the Newton-Raphson and successive substitution methods. Application and verification of this invention are provided through an example problem, which demonstrates that the predictions of the present invention compare most reasonably with test data.

  14. Parallel and Distributed System Simulation

    NASA Technical Reports Server (NTRS)

    Dongarra, Jack

    1998-01-01

    This exploratory study initiated our research into the software infrastructure necessary to support the modeling and simulation techniques that are most appropriate for the Information Power Grid. Such computational power grids will use high-performance networking to connect hardware, software, instruments, databases, and people into a seamless web that supports a new generation of computation-rich problem solving environments for scientists and engineers. In this context we looked at evaluating the NetSolve software environment for network computing that leverages the potential of such systems while addressing their complexities. NetSolve's main purpose is to enable the creation of complex applications that harness the immense power of the grid, yet are simple to use and easy to deploy. NetSolve uses a modular, client-agent-server architecture to create a system that is very easy to use. Moreover, it is designed to be highly composable in that it readily permits new resources to be added by anyone willing to do so. In these respects NetSolve is to the Grid what the World Wide Web is to the Internet. But like the Web, the design that makes these wonderful features possible can also impose significant limitations on the performance and robustness of a NetSolve system. This project explored the design innovations that push the performance and robustness of the NetSolve paradigm as far as possible without sacrificing the Web-like ease of use and composability that make it so powerful.

  15. A dynamic simulation model for power plants with atmospheric and pressurized circulating fluidized bed combustion -- Interactions of plant components and design studies

    SciTech Connect

    Glasmacher-Remberg, C.; Fett, F.N.

    1999-07-01

    Power plants with atmospheric or pressurized circulating fluidized bed combustion are complex technical systems. The operation characteristics of these power plants depend on the behavior of the single components and their interactions. The theoretical understanding of power plant processes of this kind as well as the design, the reliability and the practical operation can be enhanced by the application of mathematical models for the complete process. A dynamic simulation model for power plants with atmospheric circulating fluidized bed combustion (ACFBC) and pressurized circulating fluidized bed combustion (PCFBC) consisting of comprehensive submodels for the subsystems gas turbine, circulating fluidized bed combustor and water/steam cycle is presented. Apart from the investigation of the complete power plant, the simulation program enables the analysis of the three mentioned subsystems separately. Each subsystem is described by a set of unsteady-state differential and algebraic equations solved by an implicit Euler-method using a modified Newton-Raphson method. With the aid of the dynamic simulation program for a selected power plant, the effect of changes in plant operation will be examined for full and part load as well as the transient response of the system due to the carried out operation. Emphasis is laid on the characterization of the interactions between the subsystems. The dynamic simulation program can be used for design studies and it is investigated how changes of the plant design influence the operation characteristics of the example plant.

  16. Simulation models of the interactions between herbivore foraging strategies, social behavior, and plant community dynamics.

    PubMed

    Seabloom, E W; Reichman, O J

    2001-01-01

    Herbivory often operates through a feedback in which herbivores affect the success and location of plants, which in turn affects the foraging behavior of animals. Factors other than food, such as social behavior, may influence the interactions between herbivores and the plants they consume. We used a simulation model to compare the effects of foraging and social behavior on plant distribution and foraging efficiency by gophers (Thomomys bottae) in a system characteristic of California grasslands. In this system, annual forbs are the preferred food items, and their abundance increases in areas disturbed by gopher burrowing. In addition, gopher social interactions generate buffer zones between adjacent burrows. During the first year of the simulations, before gophers affected the plant community, feeding efficiency declined with increased gopher density. However, after 40 yr, annual plant abundance increased with increasing gopher density, yielding higher maximum gopher density and per capita foraging efficiency. Conversely, increased width of the buffer zones lowered maximum gopher density and annual plant abundance resulting in lower feeding efficiency. In addition, the compact burrow structure of gophers employing an area-restricted search strategy allowed a higher density of gophers to coexist, resulting in higher annual plant abundance and higher per capita food-capture rates. PMID:18707237

  17. Water uptake efficiency of a maize plant - A simulation case study

    NASA Astrophysics Data System (ADS)

    Meunier, Félicien; Leitner, Daniel; Bodner, Gernot; Javaux, Mathieu; Schnepf, Andrea

    2014-05-01

    Water uptake by plant roots is a complex mechanism controlled by biological and physical properties of the soil-plant-atmosphere system and affects a major component of the water cycle, transpiration. This uptake of water by plants is one of the major factors of plant development. Since water uptake occurs at the roots, root architecture and hydraulic properties both play a crucial role in plant productivity. A fundamental understanding of the main processes of water uptake will enable better breeding of drought resistant plants and the improvement of irrigation strategies. In this work we analyzed the differences of root water uptake between idealized genotypes of a plant using mathematical modelling The numerical simulations were performed by the R-SWMS software (Javaux et al., 2008). The model describes 3-D water movement in soil by solving Richard's equation with a sink term representing root uptake. Water flow within the root xylem network and between soil and root is modelled based on water pressure gradients and calculated according to Doussan's model. The sink term is calculated by integration of local uptakes within rooted representative elementary volumes of soil. The plant water demand is described by a boundary condition at the base of the shoot. We compare the water uptake efficiency of three types of root system architectures of a maize plant. Two are actual architectures from genotypes showing significant differences regarding the internodal distance, the root growth rate and the insertion angle of their primary roots. The third one is an ideotype according to Lynch of the maize plant designed to perform better in one dry environment. We generated with RootBox five repetitions of these three root systems with the same total root volume and simulated two drought scenarios at the flowering stage (lack of water at the top or at the bottom of the soil domain). We did these simulations for two distinct distributions of local conductivities of root

  18. Implementation of a wastewater treatment plant operation support tool based on on-line simulation.

    PubMed

    Jumar, U; Tschepetzki, R

    2002-01-01

    The operators of modern wastewater treatment plants (WWTPs) are faced with increasing demands. Beyond the requirement to consistently meet discharge limits for pollutant loads, the cost efficiency of plant operation is becoming more and more important. This results in new challenges for automatic control and human control action. On-line simulation opens up interesting perspectives to provide comprehensive process information, serving as a base for optimised operation of WWTPs. This paper describes the development and application of a computer analysis and support tool for the large-scale municipal WWTP of the city of Magdeburg, Germany. It will show that by linking a simulation server to the Distributed Control System (DCS) relevant additional features for plant control arise. A good cost-benefit ratio of the system is achieved by using web techniques for implementing the software. PMID:11936673

  19. DDS: The Dental Diagnostic Simulation System.

    ERIC Educational Resources Information Center

    Tira, Daniel E.

    The Dental Diagnostic Simulation (DDS) System provides an alternative to simulation systems which represent diagnostic case studies of relatively limited scope. It may be used to generate simulated case studies in all of the dental specialty areas with case materials progressing through the gamut of the diagnostic process. The generation of a…

  20. Advanced virtual energy simulation training and research: IGCC with CO2 capture power plant

    SciTech Connect

    Zitney, S.; Liese, E.; Mahapatra, P.; Bhattacharyya, D.; Provost, G.

    2011-01-01

    In this presentation, we highlight the deployment of a real-time dynamic simulator of an integrated gasification combined cycle (IGCC) power plant with CO{sub 2} capture at the Department of Energy's (DOE) National Energy Technology Laboratory's (NETL) Advanced Virtual Energy Simulation Training and Research (AVESTARTM) Center. The Center was established as part of the DOE's accelerating initiative to advance new clean coal technology for power generation. IGCC systems are an attractive technology option, generating low-cost electricity by converting coal and/or other fuels into a clean synthesis gas mixture in a process that is efficient and environmentally superior to conventional power plants. The IGCC dynamic simulator builds on, and reaches beyond, conventional power plant simulators to merge, for the first time, a 'gasification with CO{sub 2} capture' process simulator with a 'combined-cycle' power simulator. Fueled with coal, petroleum coke, and/or biomass, the gasification island of the simulated IGCC plant consists of two oxygen-blown, downward-fired, entrained-flow, slagging gasifiers with radiant syngas coolers and two-stage sour shift reactors, followed by a dual-stage acid gas removal process for CO{sub 2} capture. The combined cycle island consists of two F-class gas turbines, steam turbine, and a heat recovery steam generator with three-pressure levels. The dynamic simulator can be used for normal base-load operation, as well as plant start-up and shut down. The real-time dynamic simulator also responds satisfactorily to process disturbances, feedstock blending and switchovers, fluctuations in ambient conditions, and power demand load shedding. In addition, the full-scope simulator handles a wide range of abnormal situations, including equipment malfunctions and failures, together with changes initiated through actions from plant field operators. By providing a comprehensive IGCC operator training system, the AVESTAR Center is poised to develop a

  1. Seismic monitoring system replacement at Temelin plant

    SciTech Connect

    Baltus, R.; Palusamy, S.S.

    1996-12-01

    The VVER-1000 plants under construction at Temelin (Czech Republic) were designed with an automatic reactor trip system triggered on seismic peak accelerations. Within the plant I and C upgrade, Westinghouse designed a digital Seismic Monitoring System to be integrated in an Artificial Intelligence based Diagnostic and Monitoring System. The system meets the requirements of the emerging standards prepared by the US NRC on the basis of EPRI studies, which recommend a detailed data evaluation and a pre-shutdown plant inspection before orderly shutdown, if required, rather than immediate emergency shutdown. The paper presents the arguments about automatic trip, as discussed in an IAEA meeting attended by expert consultants from Japan, Russia, US and Eastern and Western Europe. It describes the system installed at Temelin, including the plant specific criteria for OBE exceedance. Finally it presents the capabilities and limitations of the integration into an overall Diagnostic and Monitoring System.

  2. Space shuttle visual simulation system design study

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A recommendation and a specification for the visual simulation system design for the space shuttle mission simulator are presented. A recommended visual system is described which most nearly meets the visual design requirements. The cost analysis of the recommended system covering design, development, manufacturing, and installation is reported. Four alternate systems are analyzed.

  3. SARDA HITL Simulations: System Performance Results

    NASA Technical Reports Server (NTRS)

    Gupta, Gautam

    2012-01-01

    This presentation gives an overview of the 2012 SARDA human-in-the-loop simulation, and presents a summary of system performance results from the simulation, including delay, throughput and fuel consumption

  4. Computer simulation of coal preparation plants. Part 2. User's manual. Final report

    SciTech Connect

    Gottfried, B.S.; Tierney, J.W.

    1985-12-01

    This report describes a comprehensive computer program that allows the user to simulate the performance of realistic coal preparation plants. The program is very flexible in the sense that it can accommodate any particular plant configuration that may be of interest. This allows the user to compare the performance of different plant configurations and to determine the impact of various modes of operation with the same configuration. In addition, the program can be used to assess the degree of cleaning obtained with different coal feeds for a given plant configuration and a given mode of operation. Use of the simulator requires that the user specify the appearance of the plant configuration, the plant operating conditions, and a description of the coal feed. The simulator will then determine the flowrates within the plant, and a description of each flowrate (i.e., the weight distribution, percent ash, pyritic sulfur and total sulfur, moisture, and Btu content). The simulation program has been written in modular form using the Fortran language. It can be implemented on a great many different types of computers, ranging from large scientific mainframes to IBM-type personal computers with a fixed disk. Some customization may be required, however, to ensure compatibility with the features of Fortran available on a particular computer. Part I of this report contains a general description of the methods used to carry out the simulation. Each of the major types of units is described separately, in addition to a description of the overall system analysis. Part II is intended as a user's manual. It contains a listing of the mainframe version of the program, instructions for its use (on both a mainframe and a microcomputer), and output for a representative sample problem.

  5. Simulation system of airborne FLIR searcher

    NASA Astrophysics Data System (ADS)

    Sun, Kefeng; Li, Yu; Gao, Jiaobo; Wang, Jun; Wang, Jilong; Xie, Junhu; Ding, Na; Sun, Dandan

    2014-11-01

    Airborne Forward looking infra-red (FLIR) searcher simulation system can provide multi-mode simulated test environment that almost actual field environment, and can simulate integrated performance and external interface of airborne FLIR simulation system. Furthermore, the airborne FLIR searcher simulation system can support the algorithm optimization of image processing, and support the test and evaluation of electro-optical system, and also support the line test of software and evaluate the performance of the avionics system. The detailed design structure and information cross-linking relationship of each component are given in this paper. The simulation system is composed of the simulation center, the FLIR actuator, the FLIR emulator, and the display control terminal. The simulation center can generate the simulated target and aircraft flying data in the operation state of the airborne FLIR Searcher. The FLIR actuator can provide simulation scene. It can generate the infrared target and landform based scanning scene, response to the commands from simulation center and the FLIR actuator and operation control unit. The infrared image generated by the FLIR actuator can be processed by the FLIR emulator using PowerPC hardware framework and processing software based on VxWorks system. It can detect multi-target and output the DVI video and the multi-target detection information which corresponds to the working state of the FLIR searcher. Display control terminal can display the multi-target detection information in two-dimension situation format, and realize human-computer interaction function.

  6. Improving pumping system efficiency at coal plants

    SciTech Connect

    Livoti, W.C.; McCandless, S.; Poltorak, R.

    2009-03-15

    The industry must employ ultramodern technologies when building or upgrading power plant pumping systems thereby using fuels more efficiently. The article discusses the uses and efficiencies of positive displacement pumps, centrifugal pumps and multiple screw pumps. 1 ref., 4 figs.

  7. Improvements to information management systems simulator

    NASA Technical Reports Server (NTRS)

    Bilek, R. W.

    1972-01-01

    The performance of personnel in the augmentation and improvement of the interactive IMSIM information management simulation model is summarized. With this augmented model, NASA now has even greater capabilities for the simulation of computer system configurations, data processing loads imposed on these configurations, and executive software to control system operations. Through these simulations, NASA has an extremely cost effective capability for the design and analysis of computer-based data management systems.

  8. Residential photovoltaic system simulation: Thermal aspects

    NASA Astrophysics Data System (ADS)

    Hart, G. W.; Raghuraman, P.

    1982-04-01

    A TRNSYS simulation was developed to simulate the performance of utility interactive residential photovoltaic energy systems. The PV system is divided into its major functional components, which are individually described with computer models. These models are described in detail. The results of simulation and actual measured data obtained a MIT Lincoln Laboratory's Northeast Residential Station are compared. The thermal influences on the design of such photovoltaic energy systems are given particular attention.

  9. Nuclear power plant human computer interface design incorporating console simulation, operations personnel, and formal evaluation techniques

    SciTech Connect

    Chavez, C.; Edwards, R.M.; Goldberg, J.H.

    1993-12-31

    New CRT-based information displays which enhance the human machine interface are playing a very important role and are being increasingly used in control rooms since they present a higher degree of flexibility compared to conventional hardwired instrumentation. To prototype a new console configuration and information display system at the Experimental Breeder Reactor II (EBR-II), an iterative process of console simulation and evaluation involving operations personnel is being pursued. Entire panels including selector switches and information displays are simulated and driven by plant dynamical simulations with realistic responses that reproduce the actual cognitive and physical environment. Careful analysis and formal evaluation of operator interaction while using the simulated console will be conducted to determine underlying principles for effective control console design for this particular group of operation personnel. Additional iterations of design, simulation, and evaluation will then be conducted as necessary.

  10. Relativistic positioning systems: Numerical simulations

    NASA Astrophysics Data System (ADS)

    Puchades Colmenero, Neus

    The position of users located on the Earth's surface or near it may be found with the classic positioning systems (CPS). Certain information broadcast by satellites of global navigation systems, as GPS and GALILEO, may be used for positioning. The CPS are based on the Newtonian formalism, although relativistic post-Newtonian corrections are done when they are necessary. This thesis contributes to the development of a different positioning approach, which is fully relativistic from the beginning. In the relativistic positioning systems (RPS), the space-time position of any user (ship, spacecraft, and so on) can be calculated with the help of four satellites, which broadcast their proper times by means of codified electromagnetic signals. In this thesis, we have simulated satellite 4-tuples of the GPS and GALILEO constellations. If a user receives the signals from four satellites simultaneously, the emission proper times read -after decoding- are the user "emission coordinates". In order to find the user "positioning coordinates", in an appropriate almost inertial reference system, there are two possibilities: (a) the explicit relation between positioning and emission coordinates (broadcast by the satellites) is analytically found or (b) numerical codes are designed to calculate the positioning coordinates from the emission ones. Method (a) is only viable in simple ideal cases, whereas (b) allows us to consider realistic situations. In this thesis, we have designed numerical codes with the essential aim of studying two appropriate RPS, which may be generalized. Sometimes, there are two real users placed in different positions, which receive the same proper times from the same satellites; then, we say that there is bifurcation, and additional data are needed to choose the real user position. In this thesis, bifurcation is studied in detail. We have analyzed in depth two RPS models; in both, it is considered that the satellites move in the Schwarzschild's space

  11. Computer models and simulations of IGCC power plants with Canadian coals

    SciTech Connect

    Zheng, L.; Furimsky, E.

    1999-07-01

    In this paper, three steady state computer models for simulation of IGCC power plants with Shell, Texaco and BGL (British Gas Lurgi) gasifiers will be presented. All models were based on a study by Bechtel for Nova Scotia Power Corporation. They were built by using Advanced System for Process Engineering (ASPEN) steady state simulation software together with Fortran programs developed in house. Each model was integrated from several sections which can be simulated independently, such as coal preparation, gasification, gas cooling, acid gas removing, sulfur recovery, gas turbine, heat recovery steam generation, and steam cycle. A general description of each process, model's overall structure, capability, testing results, and background reference will be given. The performance of some Canadian coals on these models will be discussed as well. The authors also built a computer model of IGCC power plant with Kellogg-Rust-Westinghouse gasifier, however, due to limitation of paper length, it is not presented here.

  12. Review of Methods Related to Assessing Human Performance in Nuclear Power Plant Control Room Simulations

    SciTech Connect

    Katya L Le Blanc; Ronald L Boring; David I Gertman

    2001-11-01

    With the increased use of digital systems in Nuclear Power Plant (NPP) control rooms comes a need to thoroughly understand the human performance issues associated with digital systems. A common way to evaluate human performance is to test operators and crews in NPP control room simulators. However, it is often challenging to characterize human performance in meaningful ways when measuring performance in NPP control room simulations. A review of the literature in NPP simulator studies reveals a variety of ways to measure human performance in NPP control room simulations including direct observation, automated computer logging, recordings from physiological equipment, self-report techniques, protocol analysis and structured debriefs, and application of model-based evaluation. These methods and the particular measures used are summarized and evaluated.

  13. Knowledge-based simulation for aerospace systems

    NASA Technical Reports Server (NTRS)

    Will, Ralph W.; Sliwa, Nancy E.; Harrison, F. Wallace, Jr.

    1988-01-01

    Knowledge-based techniques, which offer many features that are desirable in the simulation and development of aerospace vehicle operations, exhibit many similarities to traditional simulation packages. The eventual solution of these systems' current symbolic processing/numeric processing interface problem will lead to continuous and discrete-event simulation capabilities in a single language, such as TS-PROLOG. Qualitative, totally-symbolic simulation methods are noted to possess several intrinsic characteristics that are especially revelatory of the system being simulated, and capable of insuring that all possible behaviors are considered.

  14. The Development of A Human Systems Simulation Laboratory: Strategic Direction

    SciTech Connect

    Jacques Hugo; Katya le Blanc; David Gertman

    2012-07-01

    The Human System Simulation Laboratory (HSSL) at the Idaho National Laboratory is one of few facilities of its kind that allows human factors researchers to evaluate various aspects of human performance and human system interaction for proposed reactor designs and upgrades. A basic system architecture, physical configuration and simulation capability were established to enable human factors researchers to support multiple, simultaneous simulations and also different power plant technologies. Although still evolving in terms of its technical and functional architecture, the HSSL is already proving its worth in supporting current and future nuclear industry needs for light water reactor sustainability and small modular reactors. The evolution of the HSSL is focused on continual physical and functional refinement to make it a fully equipped, reconfigurable facility where advanced research, testing and validation studies can be conducted on a wider range of reactor technologies. This requires the implementation of additional plant models to produce empirical research data on human performance with emerging human-system interaction technologies. Additional beneficiaries of this information include system designers and HRA practitioners. To ensure that results of control room crew studies will be generalizable to the existing and evolving fleet of US reactors, future expansion of the HSSL may also include other SMR plant models, plant-specific simulators and a generic plant model aligned to the current generation of pressurized water reactors (PWRs) and future advanced reactor designs. Collaboration with industry partners is also proving to be a vital component of the facility as this helps to establish a formal basis for current and future human performance experiments to support nuclear industry objectives. A long-range Program Plan has been developed for the HSSL to ensure that the facility will support not only the Department of Energy’s Light Water Reactor

  15. Method for simulating discontinuous physical systems

    DOEpatents

    Baty, Roy S.; Vaughn, Mark R.

    2001-01-01

    The mathematical foundations of conventional numerical simulation of physical systems provide no consistent description of the behavior of such systems when subjected to discontinuous physical influences. As a result, the numerical simulation of such problems requires ad hoc encoding of specific experimental results in order to address the behavior of such discontinuous physical systems. In the present invention, these foundations are replaced by a new combination of generalized function theory and nonstandard analysis. The result is a class of new approaches to the numerical simulation of physical systems which allows the accurate and well-behaved simulation of discontinuous and other difficult physical systems, as well as simpler physical systems. Applications of this new class of numerical simulation techniques to process control, robotics, and apparatus design are outlined.

  16. DKIST Adaptive Optics System: Simulation Results

    NASA Astrophysics Data System (ADS)

    Marino, Jose; Schmidt, Dirk

    2016-05-01

    The 4 m class Daniel K. Inouye Solar Telescope (DKIST), currently under construction, will be equipped with an ultra high order solar adaptive optics (AO) system. The requirements and capabilities of such a solar AO system are beyond those of any other solar AO system currently in operation. We must rely on solar AO simulations to estimate and quantify its performance.We present performance estimation results of the DKIST AO system obtained with a new solar AO simulation tool. This simulation tool is a flexible and fast end-to-end solar AO simulator which produces accurate solar AO simulations while taking advantage of current multi-core computer technology. It relies on full imaging simulations of the extended field Shack-Hartmann wavefront sensor (WFS), which directly includes important secondary effects such as field dependent distortions and varying contrast of the WFS sub-aperture images.

  17. Database system support for simulation data

    SciTech Connect

    Murphy, M.C.

    1989-07-01

    This report addresses database system issues arising in the design, implementation and execution of queuing simulation experiments. The primary goal is to identify new features for inclusion in a custom database system implemented using an extensible database system. Simulation data is first identified as a distinct subset of scientific data. An overview of the experimental process is then presented along with a survey of related simulation environments. A queuing simulation paradigm is described in detail in order to identify the distinguishing characteristics of queuing simulation data and the modes of manipulation. This is the basis for a traditional ER/Relational implementation, which in turn serves as the focus of a complete simulation environment. Difficulties encountered in the use of traditional implementation tools motivate the custom database system extensions. 37 refs., 5 figs., 2 tabs.

  18. Operational development of small plant growth systems

    NASA Technical Reports Server (NTRS)

    Scheld, H. W.; Magnuson, J. W.; Sauer, R. L.

    1986-01-01

    The results of a study undertaken on the first phase of an empricial effort in the development of small plant growth chambers for production of salad type vegetables on space shuttle or space station are discussed. The overall effort is visualized as providing the underpinning of practical experience in handling of plant systems in space which will provide major support for future efforts in planning, design, and construction of plant-based (phytomechanical) systems for support of human habitation in space. The assumptions underlying the effort hold that large scale phytomechanical habitability support systems for future space stations must evolve from the simple to the complex. The highly complex final systems will be developed from the accumulated experience and data gathered from repetitive tests and trials of fragments or subsystems of the whole in an operational mode. These developing system components will, meanwhile, serve a useful operational function in providing psychological support and diversion for the crews.

  19. Integrating Existing Simulation Components into a Cohesive Simulation System

    NASA Technical Reports Server (NTRS)

    McLaughlin, Brian J.; Barrett, Larry K.

    2012-01-01

    A tradition of leveraging the re-use of components to help manage costs has evolved in the development of complex system. This tradition continues on in the Joint Polar Satellite System (JPSS) Program with the cloning of the Suomi National Polar-orbiting Partnership (NPP) satellite for the JPSS-1 mission, including the instrument complement. One benefit of re-use on a mission is the availability of existing simulation assets from the systems that were previously built. An issue arises in the continual shift of technology over a long mission, or multi-mission, lifecycle. As the missions mature, the requirements for the observatory simulations evolve. The challenge in this environment becomes re-using the existing components in that ever-changing landscape. To meet this challenge, the system must: establish an operational architecture that minimizes impacts on the implementation of individual components, consolidate the satisfaction of new high-impact requirements into system-level infrastructure, and build in a long-term view of system adaptation that spans the full lifecycle of the simulation system. The Flight Vehicle Test Suite (FVTS) within the JPSS Program is defining and executing this approach to ensure a robust simulation capability for the JPSS multi-mission environment

  20. Optimization of a biological wastewater treatment process at a petrochemical plant using process simulation

    SciTech Connect

    Jones, R.M.; Dold, P.L.; Baker, A.J.; Briggs, T.

    1996-12-31

    A research study was conducted on the activated sludge process treating the wastewater from a petrochemical manufacturing facility in Ontario, Canada. The objective of the study was to improve the level of understanding of the process and to evaluate the use of model-based simulation tools as an aid in the optimization of the wastewater treatment facility. Models such as the IAWQ Activated Sludge Model No. 1 (ASM1) have previously been developed and applied to assist in designing new systems and to assist in the optimization of existing systems for the treatment of municipal wastewaters, However, due to significant differences between the characteristics of the petrochemical plant wastewater and municipal wastewaters, this study required the development of a mechanistic model specifically to describe the behavior of the activated sludge treatment of the petrochemical wastewater. This paper outlines the development of the mechanistic model and gives examples of how plant performance issues were investigated through process simulation.

  1. Simulation and comparison of different operational strategies for storage utilization in concentrated solar power plants

    NASA Astrophysics Data System (ADS)

    García-Barberena, Javier; Erdocia, Ioseba

    2016-05-01

    The increase of electric power demand and the wish to protect the environment are leading to a change in the energy sources. Conventional energy plants are losing strength against the renewable energy plants and, in particular, solar energy plants have a huge potential to provide clean energy supply for the increasing world's energy demand. Among the existing solar technologies, Concentrating Solar Power (CSP) is one of the most promising technologies. One of the major advantages of CSP plants is the technically feasible and cost-effective integration of Thermal Energy Storage (TES) systems. To increase the plant dispatchability, it is possible to create different operational strategies defining how such TES system is used. In this work, different strategies with different overall goals have been simulated over a complete year and the results are presented and compared here to demonstrate the capabilities of the operational strategies towards an increased dispatchability and plant economic effectiveness. The analysis shows that different strategies may lead to significant differences in the plant annual production, expected economic incomes, number of power block stops, mean efficiency, etc. Specifically, it has been found that the economic incomes of a plant can be increased (+1.3%) even with a decreased total energy production (-1.5%) if the production is scheduled to follow a demand/price curve. Also, dramatic reduction in the number of turbine stops (-67%) can be achieved if the plant is operated towards this objective. The strategies presented in this study have not been optimized towards any specific objective, but only created to show the potential of well designed operational strategies in CSP plants. Therefore, many other strategies as well as optimized versions of the strategies explained below are possible and will be analyzed in future works.

  2. Plants and the central nervous system.

    PubMed

    Carlini, E A

    2003-06-01

    This review article draws the attention to the many species of plants possessing activity on the central nervous system (CNS). In fact, they cover the whole spectrum of central activity such as psychoanaleptic, psycholeptic and psychodysleptic effects, and several of these plants are currently used in therapeutics to treat human ailments. Among the psychoanaleptic (stimulant) plants, those utilized by human beings to reduce body weight [Ephedra spp. (Ma Huang), Paullinia spp. (guaraná), Catha edulis Forssk. (khat)] and plants used to improve general health conditions (plant adaptogens) were scrutinized. Many species of hallucinogenic (psychodysleptic) plants are used by humans throughout the world to achieve states of mind distortions; among those, a few have been used for therapeutic purposes, such as Cannabis sativa L., Tabernanthe iboga Baill. and the mixture of Psychotria viridis Ruiz and Pav. and Banisteriopsis caapi (Spruce ex Griseb.) C.V. Morton. Plants showing central psycholeptic activities, such as analgesic or anxiolytic actions (Passiflora incarnata L., Valeriana spp. and Piper methysticum G. Forst.), were also analysed.Finally, the use of crude or semipurified extracts of such plants instead of the active substances seemingly responsible for their therapeutic effect is discussed. PMID:12895668

  3. Analysis of the use of industrial control systems in simulators: state of the art and basic guidelines.

    PubMed

    Carrasco, Juan A; Dormido, Sebastián

    2006-04-01

    The use of industrial control systems in simulators facilitates the execution of engineering activities related with the installation and the optimization of the control systems in real plants. "Industrial control system" intends to be a valid term that would represent all the control systems which can be installed in an industrial plant, ranging from complex distributed control systems and SCADA packages to small single control devices. This paper summarizes the current alternatives for the development of simulators of industrial plants and presents an analysis of the process of integrating an industrial control system into a simulator, with the aim of helping in the installation of real control systems in simulators. PMID:16649572

  4. The renewable electric plant information system

    SciTech Connect

    Sinclair, K.

    1995-12-01

    This report explains the procedures used for creating the Renewable Electric Plant Information System (REPiS) database, describes the database fields, and summarizes the data. The REPiS database contains comprehensive information on grid-connected renewable electric generation plants in the United States. Originally designed in 1987 and updated in 1990, the database includes information through 1994. The report also illustrates ways of using the data for analysis is and describes how researchers validated the data.

  5. Computer simulation of engine systems

    NASA Technical Reports Server (NTRS)

    Fishbach, L. H.

    1980-01-01

    The use of computerized simulations of the steady state and transient performance of jet engines throughout the flight regime is discussed. In addition, installation effects on thrust and specific fuel consumption is accounted for as well as engine weight, dimensions and cost. The availability throughout the government and industry of analytical methods for calculating these quantities are pointed out.

  6. Interoperability Standards for Medical Simulation Systems

    NASA Technical Reports Server (NTRS)

    Tolk, Andreas; Diallo, Saikou Y.; Padilla, Jose J.

    2012-01-01

    The Modeling and Simulation Community successfully developed and applied interoperability standards like the Distributed Interactive Simulation (DIS) protocol (IEEE 1278) and the High Level Architecture (HLA) (IEEE 1516). These standards were applied for world-wide distributed simulation events for several years. However, this paper shows that some of the assumptions and constraints underlying the philosophy of these current standards are not valid for Medical Simulation Systems. This paper describes the standards, the philosophy and the limits for medical applications and recommends necessary extensions of the standards to support medical simulation.

  7. Simulation Of Combat With An Expert System

    NASA Technical Reports Server (NTRS)

    Provenzano, J. P.

    1989-01-01

    Proposed expert system predicts outcomes of combat situations. Called "COBRA", combat outcome based on rules for attrition, system selects rules for mathematical modeling of losses and discrete events in combat according to previous experiences. Used with another software module known as the "Game". Game/COBRA software system, consisting of Game and COBRA modules, provides for both quantitative aspects and qualitative aspects in simulations of battles. COBRA intended for simulation of large-scale military exercises, concepts embodied in it have much broader applicability. In industrial research, knowledge-based system enables qualitative as well as quantitative simulations.

  8. Design of penicillin fermentation process simulation system

    NASA Astrophysics Data System (ADS)

    Qi, Xiaoyu; Yuan, Zhonghu; Qi, Xiaoxuan; Zhang, Wenqi

    2011-10-01

    Real-time monitoring for batch process attracts increasing attention. It can ensure safety and provide products with consistent quality. The design of simulation system of batch process fault diagnosis is of great significance. In this paper, penicillin fermentation, a typical non-linear, dynamic, multi-stage batch production process, is taken as the research object. A visual human-machine interactive simulation software system based on Windows operation system is developed. The simulation system can provide an effective platform for the research of batch process fault diagnosis.

  9. The application of simulation modeling to the cost and performance ranking of solar thermal power plants

    NASA Technical Reports Server (NTRS)

    Rosenberg, L. S.; Revere, W. R.; Selcuk, M. K.

    1981-01-01

    Small solar thermal power systems (up to 10 MWe in size) were tested. The solar thermal power plant ranking study was performed to aid in experiment activity and support decisions for the selection of the most appropriate technological approach. The cost and performance were determined for insolation conditions by utilizing the Solar Energy Simulation computer code (SESII). This model optimizes the size of the collector field and energy storage subsystem for given engine generator and energy transport characteristics. The development of the simulation tool, its operation, and the results achieved from the analysis are discussed.

  10. The influence of simulated low-gravity environments on growth, development and metabolism of plants.

    PubMed

    Dedolph, R R

    1967-01-01

    Low-gravity environments may be simulated through appropriate horizontal clinostat rotation. This simulation is accomplished through a biological nullification of the directional component of gravitational force. Measuring biologically effective gravity force by organ response, it is readily demonstrated that biologically active gravitational force may be treated as a two-dimensional vector. Though the magnitude dimension of this vector remains virtually constant anywhere on earth, the biologically effective direction dimension may be quantitatively altered by clinostat rotation, provided appropriate angular velocities and angles of inclination of clinostat axes are employed. Using oat seedlings, a rotation rate of 2 rpm, and a horizontal axis clinostat, a 'zero g' environment may be simulated. This simulated 'zero g' condition is attested by the inability of plants to perceive unidirectional gravitational force of sufficient magnitude to elicit directional growth. Under such conditions, plants will grow in the direction imparted by the initial orientation of the plants in the system. Geotropic curvature responses to subsequent geostimulation are, however, greater in seedlings grown under these conditions, nullifying the direction dimension of gravitational force, than in seedlings grown with rotation but with normal unidirectional gravity loads. Root growth under simulated 'zero' gravity conditions is likewise enhanced as compared to plants grown with rotation but normal unidirectional gravity. These differences in magnitude of growth and response to subsequent geostimulation are inexplicable on bases of modified auxin economy or production. Respiration rates are, however, materially enhanced by the simulated 'zero g' environments. This enhancement of respiration, as well as growth, quantitatively diminishes as the unidirectional gravity load is increased. These results imply that the primary effect of low-gravity environments is likely that of modifying the

  11. Gas Reactor Plant Analyzer and Simulator for Hydrogen Production

    Energy Science and Technology Software Center (ESTSC)

    2004-01-01

    This software is used to study and analyze various configurations of plant equipment for gas cooled nuclear reactor applications. The user of this software would likely be interested in optimizing the economic, safety, and operating performance of this type of reactor. The code provides the capability for the user through his input to configure networks of nuclear reactor components. The components available include turbine, compressor, heat exchanger, reactor core, coolers, bypass valves, and control systems.

  12. Power electronics system modeling and simulation

    SciTech Connect

    Lai, Jih-Sheng

    1994-12-31

    This paper introduces control system design based softwares, SIMNON and MATLAB/SIMULINK, for power electronics system simulation. A complete power electronics system typically consists of a rectifier bridge along with its smoothing capacitor, an inverter, and a motor. The system components, featuring discrete or continuous, linear or nonlinear, are modeled in mathematical equations. Inverter control methods,such as pulse-width-modulation and hysteresis current control, are expressed in either computer algorithms or digital circuits. After describing component models and control methods, computer programs are then developed for complete systems simulation. Simulation results are mainly used for studying system performances, such as input and output current harmonics, torque ripples, and speed responses. Key computer programs and simulation results are demonstrated for educational purposes.

  13. Resilient Plant Monitoring System: Design, Analysis, and Performance Evaluation

    SciTech Connect

    Humberto E. Garcia; Wen-Chiao Lin; Semyon M. Meerkov; Maruthi T. Ravichandran

    2013-12-01

    Resilient monitoring systems are sensor networks that degrade gracefully under malicious attacks on their sensors, causing them to project misleading information. The goal of this paper is to design, analyze, and evaluate the performance of a resilient monitoring system intended to monitor plant conditions (normal or anomalous). The architecture developed consists of four layers: data quality assessment, process variable assessment, plant condition assessment, and sensor network adaptation. Each of these layers is analyzed by either analytical or numerical tools, and the performance of the overall system is evaluated using simulations. The measure of resiliency of the resulting system is evaluated using Kullback Leibler divergence, and is shown to be sufficiently high in all scenarios considered.

  14. Global Positioning System Simulator Field Operational Procedures

    NASA Technical Reports Server (NTRS)

    Kizhner, Semion; Quinn, David A.; Day, John H. (Technical Monitor)

    2002-01-01

    Global Positioning System (GPS) simulation is an important activity in the development or qualification of GPS signal receivers for space flight. Because a GPS simulator is a critical resource it is highly desirable to develop a set of field operational procedures to supplement the basic procedures provided by most simulator vendors. Validated field procedures allow better utilization of the GPS simulator in the development of new test scenarios and simulation operations. These procedures expedite simulation scenario development while resulting in scenarios that are more representative of the true design, as well as enabling construction of more complex simulations than previously possible, for example, spacecraft maneuvers. One difficulty in the development of a simulation scenario is specifying various modes of test vehicle motion and associated maneuvers requiring that a user specify some (but not all) of a few closely related simulation parameters. Currently this can only be done by trial and error. A stand-alone procedure that implements the simulator maneuver motion equations and solves for the motion profile transient times, jerk and acceleration would be of considerable value. Another procedure would permit the specification of some configuration parameters that would determine the simulated GPS signal composition. The resulting signal navigation message, for example, would force the receiver under test to use only the intended C-code component of the simulated GPS signal. A representative class of GPS simulation-related field operational procedures is described in this paper. These procedures were developed and used in support of GPS integration and testing for many successful spacecraft missions such as SAC-A, EO-1, AMSAT, VCL, SeaStar, sounding rockets, and by using the industry standard Spirent Global Simulation Systems Incorporated (GSSI) STR series simulators.

  15. Simulation, Design Abstraction, and SystemC

    ERIC Educational Resources Information Center

    Harcourt, Ed

    2007-01-01

    SystemC is a system-level design and simulation language based on C++. We've been using SystemC for computer organization and design projects for the past several years. Because SystemC is embedded in C++ it contains the powerful abstraction mechanisms of C++ not found in traditional hardware description languages, such as support for…

  16. Simulating Rain Fade In A Communication System

    NASA Technical Reports Server (NTRS)

    Shalkhauser, Kurt A.; Nagy, Lawrence A.; Svoboda, James K.

    1994-01-01

    Automated, computer-controlled assembly of electronic equipment developed for use in simulation testing of downlink portion of Earth/satellite microwave digital communication system. Designed to show effects upon performance of system of rain-induced fading in received signal and increases in transmitted power meant to compensate for rain-induced fading. Design of communication system improved iteratively in response to results of simulations, leading eventually to design ensuring clear, uninterrupted transmission of digital signals.

  17. Characteristics of flight simulator visual systems

    NASA Technical Reports Server (NTRS)

    Statler, I. C. (Editor)

    1981-01-01

    The physical parameters of the flight simulator visual system that characterize the system and determine its fidelity are identified and defined. The characteristics of visual simulation systems are discussed in terms of the basic categories of spatial, energy, and temporal properties corresponding to the three fundamental quantities of length, mass, and time. Each of these parameters are further addressed in relation to its effect, its appropriate units or descriptors, methods of measurement, and its use or importance to image quality.

  18. Diffuse-Illumination Systems for Growing Plants

    NASA Technical Reports Server (NTRS)

    May, George; Ryan, Robert

    2010-01-01

    Agriculture in both terrestrial and space-controlled environments relies heavily on artificial illumination for efficient photosynthesis. Plant-growth illumination systems require high photon flux in the spectral range corresponding with plant photosynthetic active radiation (PAR) (400 700 nm), high spatial uniformity to promote uniform growth, and high energy efficiency to minimize electricity usage. The proposed plant-growth system takes advantage of the highly diffuse reflective surfaces on the interior of a sphere, hemisphere, or other nearly enclosed structure that is coated with highly reflective materials. This type of surface and structure uniformly mixes discrete light sources to produce highly uniform illumination. Multiple reflections from within the domelike structures are exploited to obtain diffuse illumination, which promotes the efficient reuse of photons that have not yet been absorbed by plants. The highly reflective surfaces encourage only the plant tissue (placed inside the sphere or enclosure) to absorb the light. Discrete light sources, such as light emitting diodes (LEDs), are typically used because of their high efficiency, wavelength selection, and electronically dimmable properties. The light sources are arranged to minimize shadowing and to improve uniformity. Different wavelengths of LEDs (typically blue, green, and red) are used for photosynthesis. Wavelengths outside the PAR range can be added for plant diagnostics or for growth regulation

  19. Computer simulation of breathing systems for divers

    SciTech Connect

    Sexton, P.G.; Nuckols, M.L.

    1983-02-01

    A powerful new tool for the analysis and design of underwater breathing gas systems is being developed. A versatile computer simulator is described which makes possible the modular ''construction'' of any conceivable breathing gas system from computer memory-resident components. The analysis of a typical breathing gas system is demonstrated using this simulation technique, and the effects of system modifications on performance of the breathing system are shown. This modeling technique will ultimately serve as the foundation for a proposed breathing system simulator under development by the Navy. The marriage of this computer modeling technique with an interactive graphics system will provide the designer with an efficient, cost-effective tool for the development of new and improved diving systems.

  20. Air Storage System Energy Transfer (ASSET) plants

    NASA Astrophysics Data System (ADS)

    Stys, Z. S.

    1983-09-01

    The design features and performance capabilities of Air Storage System Energy Transfer (ASSET) plants for transferring off-peak utility electricity to on-peak hours are described. The plant operations involve compressing ambient air with an axial flow compressor and depositing it in an underground reservoir at 70 bar pressure. Released during a peaking cycle, the pressure is reduced to 43 bar, the air is heated to 550 C, passed through an expander after a turbine, and passed through a low pressure combustion chamber to be heated to 850 C. A West German plant built in 1978 to supply over 300 MW continuous power for up to two hours is detailed, noting its availability factor of nearly 98 percent and power delivery cost of $230/kW installed. A plant being constructed in Illinois will use limestone caverns as the air storage tank.

  1. Solar simulator for concentrator photovoltaic systems.

    PubMed

    Domínguez, César; Antón, Ignacio; Sala, Gabriel

    2008-09-15

    A solar simulator for measuring performance of large area concentrator photovoltaic (CPV) modules is presented. Its illumination system is based on a Xenon flash light and a large area collimator mirror, which simulates natural sun light. Quality requirements imposed by the CPV systems have been characterized: irradiance level and uniformity at the receiver, light collimation and spectral distribution. The simulator allows indoor fast and cost-effective performance characterization and classification of CPV systems at the production line as well as module rating carried out by laboratories. PMID:18795026

  2. An interactive beam position monitor system simulator

    SciTech Connect

    Ryan, W.A.; Shea, T.J.

    1993-03-01

    A system simulator has been implemented to aid the development of the RHIC position monitor system. Based on the LabVIEW software package by National Instruments, this simulator allows engineers and technicians to interactively explore the parameter space of a system during the design phase. Adjustable parameters are divided into three categories: beam, pickup, and electronics. The simulator uses these parameters in simple formulas to produce results in both time-domain and frequencydomain. During the prototyping phase, these simulated results can be compared to test data acquired with the same software package. The RHIC position monitor system is presented as an example, but the software is applicable to several other systems as well.

  3. ROBOSIM, a simulator for robotic systems

    NASA Technical Reports Server (NTRS)

    Hinman, Elaine M.; Fernandez, Ken; Cook, George E.

    1991-01-01

    ROBOSIM, a simulator for robotic systems, was developed by NASA to aid in the rapid prototyping of automation. ROBOSIM has allowed the development of improved robotic systems concepts for both earth-based and proposed on-orbit applications while significantly reducing development costs. In a cooperative effort with an area university, ROBOSIM was further developed for use in the classroom as a safe and cost-effective way of allowing students to study robotic systems. Students have used ROBOSIM to study existing robotic systems and systems which they have designed in the classroom. Since an advanced simulator/trainer of this type is beneficial not only to NASA projects and programs but industry and academia as well, NASA is in the process of developing this technology for wider public use. An update on the simulators's new application areas, the improvements made to the simulator's design, and current efforts to ensure the timely transfer of this technology are presented.

  4. Simulation of large systems with neural networks

    SciTech Connect

    Paez, T.L.

    1994-09-01

    Artificial neural networks (ANNs) have been shown capable of simulating the behavior of complex, nonlinear, systems, including structural systems. Under certain circumstances, it is desirable to simulate structures that are analyzed with the finite element method. For example, when we perform a probabilistic analysis with the Monte Carlo method, we usually perform numerous (hundreds or thousands of) repetitions of a response simulation with different input and system parameters to estimate the chance of specific response behaviors. In such applications, efficiency in computation of response is critical, and response simulation with ANNs can be valuable. However, finite element analyses of complex systems involve the use of models with tens or hundreds of thousands of degrees of freedom, and ANNs are practically limited to simulations that involve far fewer variables. This paper develops a technique for reducing the amount of information required to characterize the response of a general structure. We show how the reduced information can be used to train a recurrent ANN. Then the trained ANN can be used to simulate the reduced behavior of the original system, and the reduction transformation can be inverted to provide a simulation of the original system. A numerical example is presented.

  5. Dynamic system simulation of small satellite projects

    NASA Astrophysics Data System (ADS)

    Raif, Matthias; Walter, Ulrich; Bouwmeester, Jasper

    2010-11-01

    A prerequisite to accomplish a system simulation is to have a system model holding all necessary project information in a centralized repository that can be accessed and edited by all parties involved. At the Institute of Astronautics of the Technische Universitaet Muenchen a modular approach for modeling and dynamic simulation of satellite systems has been developed called dynamic system simulation (DySyS). DySyS is based on the platform independent description language SysML to model a small satellite project with respect to the system composition and dynamic behavior. A library of specific building blocks and possible relations between these blocks have been developed. From this library a system model of the satellite of interest can be created. A mapping into a C++ simulation allows the creation of an executable system model with which simulations are performed to observe the dynamic behavior of the satellite. In this paper DySyS is used to model and simulate the dynamic behavior of small satellites, because small satellite projects can act as a precursor to demonstrate the feasibility of a system model since they are less complex compared to a large scale satellite project.

  6. RNA trafficking in parasitic plant systems.

    PubMed

    Leblanc, Megan; Kim, Gunjune; Westwood, James H

    2012-01-01

    RNA trafficking in plants contributes to local and long-distance coordination of plant development and response to the environment. However, investigations of mobile RNA identity and function are hindered by the inherent difficulty of tracing a given molecule of RNA from its cell of origin to its destination. Several methods have been used to address this problem, but all are limited to some extent by constraints associated with accurately sampling phloem sap or detecting trafficked RNA. Certain parasitic plant species form symplastic connections to their hosts and thereby provide an additional system for studying RNA trafficking. The haustorial connections of Cuscuta and Phelipanche species are similar to graft junctions in that they are able to transmit mRNAs, viral RNAs, siRNAs, and proteins from the host plants to the parasite. In contrast to other graft systems, these parasites form connections with host species that span a wide phylogenetic range, such that a high degree of nucleotide sequence divergence may exist between host and parasites and allow confident identification of most host RNAs in the parasite system. The ability to identify host RNAs in parasites, and vice versa, will facilitate genomics approaches to understanding RNA trafficking. This review discusses the nature of host-parasite connections and the potential significance of host RNAs for the parasite. Additional research on host-parasite interactions is needed to interpret results of RNA trafficking studies, but parasitic plants may provide a fascinating new perspective on RNA trafficking. PMID:22936942

  7. Process simulation and economical evaluation of enzymatic biodiesel production plant.

    PubMed

    Sotoft, Lene Fjerbaek; Rong, Ben-Guang; Christensen, Knud V; Norddahl, Birgir

    2010-07-01

    Process simulation and economical evaluation of an enzymatic biodiesel production plant has been carried out. Enzymatic biodiesel production from high quality rapeseed oil and methanol has been investigated for solvent free and cosolvent production processes. Several scenarios have been investigated with different production scales (8 and 200 mio. kg biodiesel/year) and enzyme price. The cosolvent production process is found to be most expensive and is not a viable choice, while the solvent free process is viable for the larger scale production of 200 mio. kg biodiesel/year with the current enzyme price. With the suggested enzyme price of the future, both the small and large scale solvent free production proved viable. The product price was estimated to be 0.73-1.49 euro/kg biodiesel with the current enzyme price and 0.05-0.75 euro/kg with the enzyme price of the future for solvent free process. PMID:20171880

  8. Multivariable Robust Control of a Simulated Hybrid Solid Oxide Fuel Cell Gas Turbine Plant

    SciTech Connect

    Tsai, Alex; Banta, Larry; Tucker, D.A.; Gemmen, R.S.

    2008-06-01

    This paper presents a systematic approach to the multivariable robust control of a hybrid fuel cell gas turbine plant. The hybrid configuration under investigation comprises a physical simulation of a 300kW fuel cell coupled to a 120kW auxiliary power unit single spool gas turbine. The facility provides for the testing and simulation of different fuel cell models that in turn help identify the key issues encountered in the transient operation of such systems. An empirical model of the facility consisting of a simulated fuel cell cathode volume and balance of plant components is derived via frequency response data. Through the modulation of various airflow bypass valves within the hybrid configuration, Bode plots are used to derive key input/output interactions in Transfer Function format. A multivariate system is then built from individual transfer functions, creating a matrix that serves as the nominal plant in an H-Infinity robust control algorithm. The controller’s main objective is to track and maintain hybrid operational constraints in the fuel cell’s cathode airflow, and the turbo machinery states of temperature and speed, under transient disturbances. This algorithm is then tested on a Simulink/MatLab platform for various perturbations of load and fuel cell heat effluence.

  9. Particle simulation of plasmas and stellar systems

    SciTech Connect

    Tajima, T.; Clark, A.; Craddock, G.G.; Gilden, D.L.; Leung, W.K.; Li, Y.M.; Robertson, J.A.; Saltzman, B.J.

    1985-04-01

    A computational technique is introduced which allows the student and researcher an opportunity to observe the physical behavior of a class of many-body systems. A series of examples is offered which illustrates the diversity of problems that may be studied using particle simulation. These simulations were in fact assigned as homework in a course on computational physics.

  10. Instructional Simulation of a Commercial Banking System.

    ERIC Educational Resources Information Center

    Hester, Donald D.

    1991-01-01

    Describes an instructional simulation of a commercial banking system. Identifies the teaching of portfolio theory, market robustness, and the subtleties of institutional constraints and decision making under uncertainty as the project's goals. Discusses the results of applying the simulation in an environment of local and national markets and a…

  11. Crop Simulation Models and Decision Support Systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The first computer simulation models for agricultural systems were developed in the 1970s. These early models simulated potential production for major crops as a function of weather conditions, especially temperature and solar radiation. At a later stage, the water component was added to be able to ...

  12. The Canadian Hospital Executive Simulation System (CHESS).

    PubMed

    Pink, G H; Knotts, U A; Parrish, L G; Shields, C A

    1991-01-01

    The Canadian Hospital Executive Simulation System (CHESS) is a computer-based management decision-making game designed specifically for Canadian hospital managers. The paper begins with an introduction on the development of business and health services industry-specific simulation games. An overview of CHESS is provided, along with a description of its development and a discussion of its educational benefits. PMID:10109530

  13. Using Expert Systems To Build Cognitive Simulations.

    ERIC Educational Resources Information Center

    Jonassen, David H.; Wang, Sherwood

    2003-01-01

    Cognitive simulations are runnable computer programs for modeling human cognitive activities. A case study is reported where expert systems were used as a formalism for modeling metacognitive processes in a seminar. Building cognitive simulations engages intensive introspection, ownership and meaning making in learners who build them. (Author/AEF)

  14. Optimum spaceborne computer system design by simulation

    NASA Technical Reports Server (NTRS)

    Williams, T.; Kerner, H.; Weatherbee, J. E.; Taylor, D. S.; Hodges, B.

    1973-01-01

    A deterministic simulator is described which models the Automatically Reconfigurable Modular Multiprocessor System (ARMMS), a candidate computer system for future manned and unmanned space missions. Its use as a tool to study and determine the minimum computer system configuration necessary to satisfy the on-board computational requirements of a typical mission is presented. The paper describes how the computer system configuration is determined in order to satisfy the data processing demand of the various shuttle booster subsytems. The configuration which is developed as a result of studies with the simulator is optimal with respect to the efficient use of computer system resources.

  15. Optimum spaceborne computer system design by simulation

    NASA Technical Reports Server (NTRS)

    Williams, T.; Weatherbee, J. E.; Taylor, D. S.

    1972-01-01

    A deterministic digital simulation model is described which models the Automatically Reconfigurable Modular Multiprocessor System (ARMMS), a candidate computer system for future manned and unmanned space missions. Use of the model as a tool in configuring a minimum computer system for a typical mission is demonstrated. The configuration which is developed as a result of studies with the simulator is optimal with respect to the efficient use of computer system resources, i.e., the configuration derived is a minimal one. Other considerations such as increased reliability through the use of standby spares would be taken into account in the definition of a practical system for a given mission.

  16. Simulation of cooling-water discharges from power plants.

    PubMed

    Wu, J; Buchak, E M; Edinger, J E; Kolluru, V S

    2001-01-01

    Accurate simulation of the temperature distribution in a cooling lake or reservoir is often required for feasibility studies of engineering options that increase the cooling capacity of the waterbody. A three-dimensional hydrodynamic and temperature model has been developed and applied to several cooling lakes in the south-eastern United States. In this paper, the details of the modeling system are presented, along with the application to the Flint Creek Lake. PMID:11381460

  17. Simulation study of the dynamic performance of a MRC plant with refrigerant charged or leaked

    NASA Astrophysics Data System (ADS)

    Sun, Heng; Shu, Dan; Jiang, Zhihua

    2012-01-01

    The running condition of a MRC plant is affected by the charge or leakage of the refrigerant. It is significant for the design and operation of the plant. A new model which is established based on the process simulation, mass conservation and characteristics of the system was employed to study the dynamic performance in these cases. The results show that the light composition mainly affects the pressure and the heavy composition affects the liquid level of vessel more obviously. This is due to the fact that the light composition mainly stays in the vapor phase and the heavies stay in the liquid phase mostly. The case when leakages occur at different location was also studied. The results can provide useful information for the adjustment of mixture refrigerant and operation of a MRC plant.

  18. An Automated and Continuous Plant Weight Measurement System for Plant Factory.

    PubMed

    Chen, Wei-Tai; Yeh, Yu-Hui F; Liu, Ting-Yu; Lin, Ta-Te

    2016-01-01

    In plant factories, plants are usually cultivated in nutrient solution under a controllable environment. Plant quality and growth are closely monitored and precisely controlled. For plant growth evaluation, plant weight is an important and commonly used indicator. Traditional plant weight measurements are destructive and laborious. In order to measure and record the plant weight during plant growth, an automated measurement system was designed and developed herein. The weight measurement system comprises a weight measurement device and an imaging system. The weight measurement device consists of a top disk, a bottom disk, a plant holder and a load cell. The load cell with a resolution of 0.1 g converts the plant weight on the plant holder disk to an analog electrical signal for a precise measurement. The top disk and bottom disk are designed to be durable for different plant sizes, so plant weight can be measured continuously throughout the whole growth period, without hindering plant growth. The results show that plant weights measured by the weight measurement device are highly correlated with the weights estimated by the stereo-vision imaging system; hence, plant weight can be measured by either method. The weight growth of selected vegetables growing in the National Taiwan University plant factory were monitored and measured using our automated plant growth weight measurement system. The experimental results demonstrate the functionality, stability and durability of this system. The information gathered by this weight system can be valuable and beneficial for hydroponic plants monitoring research and agricultural research applications. PMID:27066040

  19. An Automated and Continuous Plant Weight Measurement System for Plant Factory

    PubMed Central

    Chen, Wei-Tai; Yeh, Yu-Hui F.; Liu, Ting-Yu; Lin, Ta-Te

    2016-01-01

    In plant factories, plants are usually cultivated in nutrient solution under a controllable environment. Plant quality and growth are closely monitored and precisely controlled. For plant growth evaluation, plant weight is an important and commonly used indicator. Traditional plant weight measurements are destructive and laborious. In order to measure and record the plant weight during plant growth, an automated measurement system was designed and developed herein. The weight measurement system comprises a weight measurement device and an imaging system. The weight measurement device consists of a top disk, a bottom disk, a plant holder and a load cell. The load cell with a resolution of 0.1 g converts the plant weight on the plant holder disk to an analog electrical signal for a precise measurement. The top disk and bottom disk are designed to be durable for different plant sizes, so plant weight can be measured continuously throughout the whole growth period, without hindering plant growth. The results show that plant weights measured by the weight measurement device are highly correlated with the weights estimated by the stereo-vision imaging system; hence, plant weight can be measured by either method. The weight growth of selected vegetables growing in the National Taiwan University plant factory were monitored and measured using our automated plant growth weight measurement system. The experimental results demonstrate the functionality, stability and durability of this system. The information gathered by this weight system can be valuable and beneficial for hydroponic plants monitoring research and agricultural research applications. PMID:27066040

  20. Mechanical compaction of Waste Isolation Pilot Plant simulated waste

    SciTech Connect

    Butcher, B.M. ); Thompson, T.W.; VanBuskirk, R.G.; Patti, N.C. )

    1991-06-01

    The investigation described in this report acquired experimental information about how materials simulating transuranic (TRU) waste compact under axial compressive stress, and used these data to define a model for use in the Waste Isolation Pilot Plant (WIPP) disposal room analyses. The first step was to determine compaction curves for various simultant materials characteristic of TRU waste. Stress-volume compaction curves for various combinations of these materials were than derived to represent the combustible, metallic, and sludge waste categories. Prediction of compaction response in this manner is considered essential for the WIPP program because of the difficulties inherent in working with real (radioactive) waste. Next, full-sized 55-gallon drums of simulated combustible, metallic, and sludge waste were axially compacted. These results provided data that can be directly applied to room consolidation and data for comparison with the predictions obtained in Part 1 of the investigation. Compaction curves, which represent the combustible, metallic, and sludge waste categories, were determined, and a curve for the averaged waste inventory of the entire repository was derived. 9 refs., 31 figs., 12 tabs.

  1. Digital simulation of stiff linear dynamic systems.

    NASA Technical Reports Server (NTRS)

    Holland, L. D.; Walsh, J. R., Jr.; Kerr, J. H.

    1972-01-01

    A method is derived for digital computer simulation of linear time-invariant systems when the insignificant eigenvalues involved in such systems are eliminated by an ALSAP root removal technique. The method is applied to a thirteenth-order dynamic system representing a passive RLC network.

  2. Teaching Environmental Systems Modelling Using Computer Simulation.

    ERIC Educational Resources Information Center

    Moffatt, Ian

    1986-01-01

    A computer modeling course in environmental systems and dynamics is presented. The course teaches senior undergraduates to analyze a system of interest, construct a system flow chart, and write computer programs to simulate real world environmental processes. An example is presented along with a course evaluation, figures, tables, and references.…

  3. A dynamic model of plants' blossom based on L-system

    NASA Astrophysics Data System (ADS)

    Zhang, Ruoran; Zhang, Wenhui; Zhu, Ying; Wang, Huijao

    2010-11-01

    The article study L-system theory to modeling a visualization system which can expresses plants' growth and blossom by the Delphi language. This is according to growth process in the topology evolution and fractal geometry shape of plant, which extracts plant's growth rules to establish blossom models. The simulation is aim at modeling dynamic procedures, which can produces the lifelike plant images and demonstrates animations of growth processes. This new model emphasizes various parts of plant between space's and time's relationships. This mathematical models use biology to produce plant compartments of blossoms on growth of plants with correct images which ranges from time to time, and provides the lifelike continual growth sequence and through the natural principles to imitates and controls plants' blossoms and plant's diseases.

  4. Numerical propulsion system simulation - An interdisciplinary approach

    NASA Technical Reports Server (NTRS)

    Nichols, Lester D.; Chamis, Christos C.

    1991-01-01

    The tremendous progress being made in computational engineering and the rapid growth in computing power that is resulting from parallel processing now make it feasible to consider the use of computer simulations to gain insights into the complex interactions in aerospace propulsion systems and to evaluate new concepts early in the design process before a commitment to hardware is made. Described here is a NASA initiative to develop a Numerical Propulsion System Simulation (NPSS) capability.

  5. Numerical propulsion system simulation: An interdisciplinary approach

    NASA Technical Reports Server (NTRS)

    Nichols, Lester D.; Chamis, Christos C.

    1991-01-01

    The tremendous progress being made in computational engineering and the rapid growth in computing power that is resulting from parallel processing now make it feasible to consider the use of computer simulations to gain insights into the complex interactions in aerospace propulsion systems and to evaluate new concepts early in the design process before a commitment to hardware is made. Described here is a NASA initiative to develop a Numerical Propulsion System Simulation (NPSS) capability.

  6. Colorimetric calibration of coupled infrared simulation system

    NASA Astrophysics Data System (ADS)

    Zhang, Ying; Fei, Jindong; Gao, Yang; Du, Jian

    2015-10-01

    In order to test 2-color infrared sensors, a coupled infrared simulation system can generate radiometric outputs with wavelengths that range from less than 3 microns to more than 12 microns. There are two channels in the coupled simulation system, optically combined by a diachronic beam combiner. Each channel has an infrared blackbody, a filter, a diaphragm, and diaphragm-motors. The system is projected to the sensor under testing by a collimator. This makes it difficult to calibrate the system with only one-band thermal imager. Errors will be caused in the radiance levels measured by the narrow band thermal imager. This paper describes colorimetric temperature measurement techniques that have been developed to perform radiometric calibrations of these infrared simulation systems above. The calibration system consists of two infrared thermal imagers; one is operated at the wavelength range of MW-IR, and the other at the range of LW-IR.

  7. Computer simulator for a mobile telephone system

    NASA Technical Reports Server (NTRS)

    Schilling, D. L.

    1981-01-01

    A software simulator was developed to assist NASA in the design of the land mobile satellite service. Structured programming techniques were used by developing the algorithm using an ALCOL-like pseudo language and then encoding the algorithm into FORTRAN 4. The basic input data to the system is a sine wave signal although future plans call for actual sampled voice as the input signal. The simulator is capable of studying all the possible combinations of types and modes of calls through the use of five communication scenarios: single hop systems; double hop, signal gateway system; double hop, double gateway system; mobile to wireline system; and wireline to mobile system. The transmitter, fading channel, and interference source simulation are also discussed.

  8. Development of a dynamic simulator for a natural gas combined cycle (NGCC) power plant with post-combustion carbon capture

    SciTech Connect

    Liese, E.; Zitney, S.

    2012-01-01

    The AVESTAR Center located at the U.S. Department of Energy’s National Energy Technology Laboratory and West Virginia University is a world-class research and training environment dedicated to using dynamic process simulation as a tool for advancing the safe, efficient and reliable operation of clean energy plants with CO{sub 2} capture. The AVESTAR Center was launched with a high-fidelity dynamic simulator for an Integrated Gasification Combined Cycle (IGCC) power plant with pre-combustion carbon capture. The IGCC dynamic simulator offers full-scope Operator Training Simulator (OTS) Human Machine Interface (HMI) graphics for realistic, real-time control room operation and is integrated with a 3D virtual Immersive Training Simulator (ITS), thus allowing joint control room and field operator training. The IGCC OTS/ITS solution combines a “gasification with CO{sub 2} capture” process simulator with a “combined cycle” power simulator into a single high-performance dynamic simulation framework. This presentation will describe progress on the development of a natural gas combined cycle (NGCC) dynamic simulator based on the syngas-fired combined cycle portion of AVESTAR’s IGCC dynamic simulator. The 574 MW gross NGCC power plant design consisting of two advanced F-class gas turbines, two heat recovery steam generators (HRSGs), and a steam turbine in a multi-shaft 2x2x1 configuration will be reviewed. Plans for integrating a post-combustion carbon capture system will also be discussed.

  9. Towards Flexible Exascale Stream Processing System Simulation

    SciTech Connect

    Li, Cheng-Hong; Nair, Ravi; Ohba, Noboyuki; Shvadron, Uzi; Zaks, Ayal; Schenfeld, Eugen

    2012-01-01

    Stream processing is an important emerging computational model for performing complex operations on and across multi-source, high-volume, unpredictable dataflows. We present Flow, a platform for parallel and distributed stream processing system simulation that provides a flexible modeling environment for analyzing stream processing applications. The Flow stream processing system simulator is a high-performance, scalable simulator that automatically parallelizes chunks of the model space and incurs near-zero synchronization overhead for acyclic stream application graphs. We show promising parallel and distributed event rates exceeding 149 million events per second on a cluster with 512 processor cores.

  10. Plant cell transformation with Agrobacterium tumefaciens under simulated microgravity

    NASA Astrophysics Data System (ADS)

    Sarnatska, Veresa; Gladun, Hanna; Padalko, Svetlana

    To investigate simulated microgravity (clinorotation) effect on plant cell transformation with Agrobacterium tumefaciens and crown gall formation, the culture of primary explants of potato and Jerusalem artichoke tubers was used. It is found that the efficiency of tumor formation and development in clinorotated explants are considerably reduced. When using the explants isolated from potato tubers clinorotated for 3, 5 and 19 days, drastic reduction of formation and development of crown gall tumors was observed. Conversely, the tumor number and their development increased when potato tubers were clinorotated for one day. As was estimated by us previously, cells of Jerusalem artichoke explants are the most sensitive to agrobacteria on 4-5 h of in vitro culturing and this time corresponds to the certain period of G1-stage of the cell cycle. We have also estimated that this period is characterized by the increase of binding of acridine orange by nuclear chromatin and increase in activity of RNA-polymerase I and II. Inoculation of explants with agrobacteria in this period was the most optimal for transformation and crown gall induction. We estimated that at four - hour clinorotation of explants the intensity of acridine orange binding to nuclei was considerably lower than on 4h in the control. At one-day clinorotation of potato tubers, a considerable increase in template accessibility of chromatin and in activity of RNA-polymerase I and II occurred. These results may serve as an evidence for the ability of plant dormant tissues to respond to microgravity. Another demonstration of dormant tissue response to changed gravity we obtained when investigating pathogenesis-related proteins (PR-proteins). PR-proteins were subjected to nondenaturing PAGE.and we have not found any effect of microgravity on PR-proteins of potato explants with normal or tumorous growth. We may suggest that such response derives from the common effects of two stress factors - wounding and changed