How to invoke your Dll using relative path

public Form1()
{
InitializeComponent();
Assembly a = Assembly.LoadFile(@"F:\by Ratno\Final Skripsi\UML Studio Project\NeutralNotation\bin\Debug\NeutralNotation.dll");
Module m = a.GetModule("NeutralNotation.dll");
Type typen = null;
foreach (Type t in m.GetTypes())
{
if (t.Name.Trim().Equals("Neutral"))
{
typen = t;
}
}

ConstructorInfo[] ci;
ci = typen.GetConstructors();
d=(AbstractDiagram.IDiagram) ci[0].Invoke(null);
toolStrip1.Items.AddRange(d.GetNotationCollection()); 

}