public WaferAreaSim(string wc, string eptParameterFile, string inputDirectory, string outputDirectory, DateTime initialDateTime, Optimiser optimiser, bool useInitialLots = false)
{
this.wc = wc;
this.inputDirectory = inputDirectory;
this.outputDirectory = outputDirectory;
this.initialDateTime = initialDateTime;
this.optimiser = optimiser;
this.useInitialLots = useInitialLots;
#region WaferFab settings
waferFabSettings = Deserializer.DeserializeWaferFabSettings(Path.Combine(inputDirectory, "SerializedFiles", $"WaferFabSettings_{wc}_WithLotStarts.dat"));
distributionReader = new EPTDistributionReader(Path.Combine(inputDirectory, "CSVs"), waferFabSettings.WorkCenters, waferFabSettings.LotStepsPerWorkStation);
// Get initial parameters
waferFabSettings.WCServiceTimeDistributions = distributionReader.GetServiceTimeDistributions(eptParameterFile);
EPTDistribution initialDist = (EPTDistribution)waferFabSettings.WCServiceTimeDistributions[wc];
InitialParameters = new Dictionary <string, Distribution> {
{ wc, optimiser.CheckInitialDistBounds(initialDist) }
};
waferFabSettings.WCOvertakingDistributions = distributionReader.GetOvertakingDistributions();
#endregion
if (useInitialLots)
{
initialLots = optimiser.GetInitialLots(wc, inputDirectory, outputDirectory, initialDateTime, waferFabSettings);
}
}
static void Main(string[] args)
{
string inputDirectory = @"C:\CSSLWaferFab\Input\WSC2021paper";
string outputDirectory = @"C:\CSSLWaferFab\Output\WaferAreaOptimiser";
ReaderWriter readerWriter = new ReaderWriter(inputDirectory, outputDirectory);
Dictionary <string, Tuple <double, double> > realQueueLengths = readerWriter.GetRealQueueLengths();
List <string> workCenters = realQueueLengths.Keys.ToList(); // All work centers
workCenters = new List <string>() // Remove to evaluate all work centers
{
"PHOTOLITH", "DRY ETCH"
};
foreach (string workCenter in workCenters)
{
#region Parameters
// Model parameters
string wc = workCenter;
DateTime initialDateTime = new DateTime(2019, 6, 1);
string eptParameterFile = @"FittedEPTParameters - 2019-06-01.csv";
bool useInitialLots = true;
Settings.WriteOutput = false;
// Simulated annealing parameters
double temp = 25;
double cooldown = 0.993; //0.995 = 1102 solutions, 0.996 = 1378 solutions, 0.997 = 1834 solutions
double meanObj = realQueueLengths[wc].Item1;
double stdObj = realQueueLengths[wc].Item2;
// Dictionary with parameters to optimise and optional weights
Dictionary <string, Parameter> parameterConfiguration = new Dictionary <string, Parameter>()
{
{ "LBWIP", new Parameter("LBWIP", false) },
{ "UBWIP", new Parameter("UBWIP", false) },
{ "Tmin", new Parameter("Tmin", false) },
{ "Tmax", new Parameter("Tmax", true) },
{ "Tdecay", new Parameter("Tdecay", true) },
{ "Cmin", new Parameter("Cmin", true) },
{ "Cmax", new Parameter("Cmax", true) },
{ "Cdecay", new Parameter("Cdecay", true) }
};
#endregion
#region Variables and instances
Optimiser optimiser = new Optimiser(wc, temp, parameterConfiguration);
optimiser.SetBounds(inputDirectory);
WaferAreaSim waferAreaSim = new WaferAreaSim(wc, eptParameterFile, inputDirectory, outputDirectory, initialDateTime, optimiser, useInitialLots);
Dictionary <string, Distribution> currentPar, nextPar, bestPar;
Tuple <double, double> currentRes, nextRes, bestRes;
double currentCost, nextCost, bestCost, deltaCost;
Dictionary <WIPDepDistParameters, Tuple <double, double> > results = new Dictionary <WIPDepDistParameters, Tuple <double, double> >(); // Save all solutions
UniformDistribution uDist = new UniformDistribution(0, 1);
#endregion
#region Simulated annealing algorithm
// Initial model parameters and results
currentPar = waferAreaSim.InitialParameters;
bestPar = optimiser.CopyParameters(currentPar);
currentRes = waferAreaSim.RunSim(currentPar);
bestRes = optimiser.CopyResults(currentRes);
currentCost = Math.Abs(currentRes.Item1 - meanObj) + 0.5 * Math.Abs(currentRes.Item2 - stdObj);
bestCost = currentCost;
optimiser.AddResult(results, currentPar, currentRes);
// Iterate and evaluate solutions until sufficiently cooled down
int i = 0;
while (temp > 0.1 && currentCost > Math.Min(1, 0.1 * (meanObj + stdObj))) // If a good solution is found, stop searching
{
nextPar = optimiser.GenerateNeighbour(currentPar, temp);
nextRes = waferAreaSim.RunSim(nextPar);
nextCost = Math.Abs(nextRes.Item1 - meanObj) + 0.5 * Math.Abs(nextRes.Item2 - stdObj);
optimiser.AddResult(results, nextPar, nextRes);
if (nextCost < currentCost) // New solution is better than current, accept new solution
{
currentPar = optimiser.CopyParameters(nextPar);
currentRes = optimiser.CopyResults(nextRes);
currentCost = nextCost;
if (nextCost < bestCost) // New solution is better best, accept new best solution
{
bestPar = optimiser.CopyParameters(nextPar);
bestRes = optimiser.CopyResults(nextRes);
bestCost = nextCost;
}
}
else
{
deltaCost = nextCost - currentCost;
if (uDist.Next() < Math.Pow(Math.E, -deltaCost / temp)) // Accept solution if u ~ U[0,1] < e^-(dC/T)
{
currentPar = optimiser.CopyParameters(nextPar);
currentRes = optimiser.CopyResults(nextRes);
currentCost = nextCost;
}
}
temp = temp * cooldown; // Reduce temperature
i++;
Console.WriteLine("\nResults for area {0}.", wc);
Console.WriteLine("Iteration: {0}. Temperature {1}", i, temp);
Console.WriteLine("Evaluated solution: {0}, {1}", nextRes.Item1, nextRes.Item2);
Console.WriteLine("Current solution: {0}, {1}", currentRes.Item1, currentRes.Item2);
Console.WriteLine("Best solution: {0}, {1}\n", bestRes.Item1, bestRes.Item2);
}
#endregion
#region Write results to file
// Write all results to a text file
readerWriter.WriteAllSolutions(results, wc);
// Write the best and current solution to a text file
readerWriter.WriteFinalSolutions(currentPar, currentRes, bestPar, bestRes, wc);
#endregion
}
}