Problem Solving Environements

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Problem Solving Environements

• WebPDELab
• Online Problem Solving Environment for
  Partial Differential Equations Applications a
  Web Server for the PELLPACK PSE
• GasTurbnLab
• Multidisciplinary Agent-based Problem Solving
  Environment for the Distributed Network
  Simulation of Gas Turbine Engines

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PELLPACKA Problem Solving Environment for PDE
Applications

• Sophisticated, comprehensive system for modeling
  physical objects described by Partial
  Differential Equations
• Used by hundreds of students and faculty at
  Purdue University, nationally and internationally
  over the past decade
• Applications include physics, liquid crystal
  droplets, proton flux propagation, thermal field
  analysis, fluid dynamics, semiconductors,
  geophysical research, electromagnetic field
  analysis, thermo-elasticity, structural analysis,
  and many other scientific and engineering areas

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PELLPACK The Layered Structure
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PELLPACK The Complexity of System Installation
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WebPDELabOnline PELLPACK Problem Solving
Environment

• Complete Internet-based support for sequential
  parallel PDE computing from any Java-enabled
  browser
• Backed by 16 CPU Intel cluster connected through
  an Intel Express510t switch with Intel Ether
  Express Pro 100NICs at 100MB
• Users define, solve and analyze PDE problems
  supported by an interactive GUI for problem
  definition visualization, with full access to
  the PELLPACK libraries of PDE solvers
• Implemented using VNC remote display for the
  PELLPACK X-windows programs compiled on an i86pc
  SunOS 5.6 machine

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WebPDELab Usage Statistics for Server Access
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WebPDELab Implementation of an Online PDE PSE
WebPDELab Manager
USER
Java enabled browser
CGI
VNC viewer
HTTP
WebPDELab - VNC interface
Server Security Wrapper
Two 16 CPU i86pc Clusters
VNC Server
PELLPACK Security Wrapper
PELLPACK
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WebPDELab The Network Scenario
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Gas Turbine Engine Simulation
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GasTurbnLab

• Multi-disciplinary Problem Solving Environment
• Geometric decomposition of target simulation
  object defines a network of PDE problems
• Specialized PDE solvers (legacy code) model the
  physics on each geometric domain
• Domain interfaces are handled by mediators
• Goal generalize framework templates for an
  agent-based distributed network implementation
  of an MPSE

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GasTurbnLab The Network Scenario
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GasTurbnLabThe Agent-based Infrastructure
ModelingAgent
Graphical User Interface
Simulation ControlAgent
VisualizerAgent
Iris Explorer Platform
Grasshopper Platform
LegacyAgent
LegacyAgent
LegacyAgent
LegacyAgent
LegacyAgent
LegacyAgent
ResourceAgent
DatabaseAgent
MediatorAgent
MediatorAgent
MediatorAgent
MediatorAgent
MediatorAgent
Computational Agents
Service Agents
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GasTurbnLabPrototype Results from the
VisualizerAgent
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GasTurbnLabFramework for Implementing the
LegacyAgent
Fortran Legacy Code
Java data object to/from network simulation contr
oller
Java Agent Wrapper
C data
Fortran --- C I/O Transfer
C Wrapper
across JNI interface
Java-C data transfer for mediated data
Fortran-C data transfer for mediated data
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GasTurbnLabTemplate for the Java Agent Wrapper

• // TEMPLATE Java Agent Wrapper for C-wrapped
  Legacy Code
• public class LegacyAgent extends MobileAgent
  implements ILegacyAgent
• int startup, ret, render
• SerialData sData
• // Load library containing legacy code, C
  wrapper, legacy-wrapper data interface
• static System.loadLibrary(LegacyWrapper)
  )
• public native int LegacyWrapper(int startup,
  int render, ltlegacy specific parametersgt)
• // IO iteration Java-To-C interface
• public SerialData requestConfirmation( int
  domain, SerialData sd, int Render,
• ltlegacy specific parametersgt) throws
  agentException
• int startup1 ret1 Render0
• if (startup gt 1) copyData (sd)
  // create Java data object at every IO iteration
• retLegacyWrapper(startup,Render, ltlegacy
  specific parametersgt) // call C wrapper
• dp while (ret1) startup
• public void CopyData( SerialData sd)
  ltlegacy code specificgt // C data -gt Java
  object

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GasTurbnLabC Wrapper Template for the Legacy Code

• // TEMPLATE C Wrapper for Legacy Code
• struct int wrapperSleep int legacySleep
  // execution control
• struct ltlegacy code specificgt
  // legacy mediator data
• static void CopyData(jenv, this, start, type,
  render) // C struct to Java object at return
  to agent
• ltlegacy code specificgt
  // Java object to C struct on
  return from agent
• JNIEXPORT jint JNICALL Java_LegacyAgent_LegacyWrap
  per
• (JNIEnv env, jobject this, jint startup, jint
  render, ltlegacy code specificgt)
• int i, ret
• thread_t thr
• if (startup 1)
• if ( ret thr_create( NULL, 0, thread,
  NULL, THR_DETACHED, thr)) ! 0) // start
  legacy thread
• exit(1)
• else CopyData(jenv, this JavaToC )
  // copy mediated data from Java to C
• control.wrapperSleep1 control.legacySleep0
  // wrapper sleeps while legacy code
  executes
• while (control.wrapperSleep) (sleep(1))
• CopyData (jenv, this, startup, CToJava,
  render) // copy mediated data from C to
  Java and

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GasTurbnLabTemplate for the Data Transfer
Fortran C

• // TEMPLATE C code for transfer of I/O data from
  Fortran to C
• extern struct int wrapperSleep int
  legacySleep // execution control
• extern struct ltlegacy code specificgt
  // legacy mediator data
• / called from inside Fortran legacy code at I/O
  iteration location
• where mediated data is needed /
• void legacyDataIO (ltlegacy code specificgt)
• CopyFortran2C (ltlegacy code specificgt)
  // copy Fortran data to C struct
• control.legacySleep1 control.wrapperSleep0
  // wake wrapper and
• while (control.legacySleep) sleep(1)
  // resume at return from agent
• CopyC2Fortran (ltlegacy code specificgt)
  // copy C struct to Fortran

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GasTurbnLabTemplate for Legacy Code Modifications

• ?From a Fortran executable
• The Fortran main is changed to a subroutine
  with arguments passed as parameters
• This subroutine is started as a thread from the
  C wrapper
• A call to the I/O data transfer routine is
  inserted into the Fortran iteration loop
• The Fortran code, C routine for I/O transfer, and
  the C wrapper are compiled together as a library
  loaded into the Java agent
• ?To a C-wrapped Legacy Code Library

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GasTurbnLabAgents and the MPSE Simulation

• Completed AleAgent for simulating rotor and
  stator domains, KivaAgent for simulating
  combustor domain two MediatorAgents for
  interface data interpolation of rotor-stator and
  stator-combustor
• Completed SCA to control total simulation
  process for any number and type of domains
  VisualizerAgent to view intermediate and final
  results
• Verified mediated stator-rotor simulation,
  mediated stator-combustor simulation