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Table 1 Synthetic deviations introduced - parameter, magnitude, and detection result

From: A model for preemptive maintenance of medical linear accelerators—predictive maintenance

No. PARAMETER ERROR DESCRIPTION ERROR LEVEL DETECTION
1 PFN High Voltage Power Supply Current (A) 5 % based on operating ranges 1.05 YES
2 PFN Actual Voltage (KV) 5 % based on operating ranges 1.05 YES
3 RF Driver Voltage (V) 1STD 0.5 YES
4 RF Forward Power (W) 1STD 0.11 YES
5 AFC Error (V) 1STD 0.03 YES
6 Gun Current (A) No change—add 0 N/A
7 Gun High Voltage (V) 1STD 559 YES
8 Gun Grid Voltage (V) 1STD 7.94 YES
9 Gun Filament Step Voltage (V) Half of minor fault change 0.1 YES
10 Gun Filament Voltage (V) Half of minor fault change 0.1 YES
11 Bend Magnet Current (A) 1 % change 1.01 YES
12 Bend Magnet Voltage (V) 5 % change 1.05 YES
13 Accelerator Solenoid Current (A) 1STD 1 YES
14 Klystron Solenoid Current (A) .100 A change 0.1 YES
15 Radial Symmetry (%) 0.5 % added 0.5 YES
16 Transverse Symmetry (%) 0.5 % added 0.5 YES
17 Target Current (nC) 1STD 11 YES
18 Buncher Radial Current (A) 1STD 0.13 YES
19 Buncher Transverse Current (A) 1STD 0.1 YES
20 Angle Radial Current (A) Shift/add 0.2 A 0.2 YES
21 Angle Transverse Current (A) Shift/add 0.2 A 0.2 YES
22 Position Radial Current (A) Shift/add 0.2 A 0.2 NO
23 Position Transverse Current (A) Shift/add 0.2 A 0.2 YES
24 Trim: (A) 1STD 0.055 YES
25 Accelerator Vacion Current (uA) Add .1 % of Vac2 fault value 0.007 YES
26 Positive 5 V dc Shift/add 0.1 V 0.1 YES
27 Positive 24 V dc Shift/add 0.1 V 0.1 NO
28 Analog Negative 5 V dc Shift/add 0.1 V 0.1 YES
29 Analog Positive 5 V dc Shift/add 0.1 V 0.1 YES
30 Negative 12 V dc Shift/add 0.1 V 0.1 YES
31 Positive 3 V dc Shift/add 0.1 V 0.1 YES
32 Node Power Supply Voltage (V) Shift/add 0.1 V 0.1 YES
33 Water Level No change—add 0 N/A
34 Internal Water Supply Temperature (deg C) 1 degree change 1 YES
35 Gas Pressure (PSI) 1 psi 1 YES
36 Y1 Add 0.2 cm 0.2 YES
37 Y2 Add 0.2 cm 0.2 YES
38 X1 Add 0.2 cm 0.2 YES
39 X2 Add 0.2 cm 0.2 YES
40 Carriage A Add 0.2 cm 0.2 YES
41 Carriage B Add 0.2 cm 0.2 YES
42 Gantry—Speed 1, Speed 2 Add 0.2 deg/sec 0.2 YES
43 Gantry—cross-correlation max value Shift 10 snapshots 0.2 deg YES
44 Gantry—location of cross-correlation max value Shift 10 snapshots 0.2 deg NO
45 MLC Bank A (60 leaves)—each leaf: Speed 1, Speed 2 Add 0.1 cm/sec 0.1 YES
46 MLC Bank B (60 leaves)—each leaf: Speed 1, Speed 2 Add 0.1 cm/sec 0.1 YES
47 MLC Bank A (60 leaves)—each leaf: cross-correlation max value Shift 2 snapshots 1 mm NO
48 MLC Bank A (60 leaves)—each leaf: location of cross-correlation max value Shift 2 snapshots 1 mm YES
49 MLC Bank B (60 leaves)—each leaf: cross-correlation max value Shift 2 snapshots 1 mm NO
50 MLC Bank B (60 leaves)—each leaf: location of cross-correlation max value Shift 2 snapshots 1 mm YES