i have written this code
dt.StartBoundary = DateTime.Today + TimeSpan.FromHours(23);
dt.Repetition.Interval = TimeSpan.FromHours(3);
dt.StartBoundary = DateTime.Today + TimeSpan.FromHours(23);
dt.Repetition.Interval = TimeSpan.FromHours(3);
dt.Repetition.Duration = TimeSpan.FromHours(4);