Figure 1
FRIENDS system architecture: (a) Device placement on ENDS; (b) user interaction with sensors; (c) graphical interface; (d) extended POSIX timestamp file; (e) converted timestamp file; (f) extracted event data; (g) graph of collected data, including EM detections, touches and temperature readings.
Table 1
Formatting of original and converted timestamp.
| EXTENDED POSIX TIMESTAMP | EVENT CODE | STANDARD POSIX IN HEX | FRACTIONAL PART | EVENT | CONVERTED TIMESTAMP |
|---|---|---|---|---|---|
| 100065CA42C88D44 | 1000 | 65CA42C8 | 8D44 | PUFF ON | PUFF_ON 2024-02-12 10:09:44.551819 |
| 200065CA42C9AAE0 | 2000 | 65CA42C9 | AAE0 | PUFF OFF | PUFF_OFF 2024-02-12 10:09:45.667480 |
| 50000000000001F9 | 5000 | – | – | TEMPERATURE ON | TEMPERATURE_ON 505 |
| 6000000000000104 | 6000 | – | – | TEMPERATURE OFF | TEMPERATURE_OFF 260 |
| 300065CA42CE04A0 | 3000 | 65CA42CE | 04A0 | TOUCH ON | TOUCH_ON 2024-02-12 10:09:50.018066 |
| 400065CA42D007CD | 4000 | 65CA42D0 | 07CD | TOUCH OFF | TOUCH_OFF 2024-02-12 10:09:52.030472 |
Figure 2
The main window of the FRIENDS GUI.
Figure 3
Flow Diagram of FRIENDS GUI.
Table 2
Comparison of actual and software-analyzed data for puff quantity and duration.
| NUMBER OF PUFFS | TOTAL PUFFING DURATION (SEC) | MISSING DURATION | |||||
|---|---|---|---|---|---|---|---|
| ACTUAL | RECORDED IN DEVICE (RAW) | RECORDED IN DEVICE (1.0S FILTER) | ACTUAL | RECORDED IN DEVICE (RAW) | RECORDED IN DEVICE (1.0S FILTER) | ||
| Midnight | 18 | 20 | 18 | 59.09 | 56.77 | 56.77 | 3.92% |
| Morning | 18 | 19 | 18 | 57.85 | 59.06 | 59.06 | –2.09% |
| Afternoon | 18 | 19 | 18 | 57.80 | 57.69 | 57.69 | 0.19% |
| Evening | 18 | 31 | 18 | 57.27 | 58.54 | 57.24 | 0.05% |
| Total | 72 | 89 | 72 | 232.01 | 232.06 | 230.76 | 0.54% |
Table 3
Assessment of Time Tracking, Conversion and Timing Discrepancies.
| SESSION | INTENDED DURATION (S) | DURATION (S) FROM VAPE DISPLAY | FROM WEBSITE (ACTUAL TIME) | FROM GUI (PROCESSED TIME) | APPROX. AVERAGE TIME DISCREPANCY (A-A’) OR (B-B’) | ||
|---|---|---|---|---|---|---|---|
| PUFF_ON TIME (A) | PUFF_OFF TIME(B) | PUFF_ON TIME (A’) | PUFF_OFF TIME (B’) | ||||
| Midnight | 2.0 | 2.28 | 01:37:02.13 | 01:37:04.50 | 01:37:01.18 | 01:37:03.37 | 1.0s |
| 3.0 | 3.19 | 01:40:31.96 | 01:40:35.13 | 01:40:30.61 | 01:40:34.11 | ||
| 4.0 | 4.34 | 01:44:37.26 | 01:44:41.60 | 01:44:36.98 | 01:44:40.36 | ||
| Morning | 2.0 | 2.24 | 08:33:34.70 | 08:33:36.98 | 08:33:31.25 | 08:33:33.43 | 4.0s |
| 3.0 | 3.09 | 08:37:07.79 | 08:37:10.91 | 08:37:04.29 | 08:37:07.36 | ||
| 4.0 | 4.20 | 08:40:38.78 | 08:40:42.94 | 08:40:35.19 | 08:40:39.37 | ||
| Afternoon | 2.0 | 2.21 | 16:47:01.76 | 16:47:04.01 | 16:46:56.18 | 16:46:58.34 | 6.0s |
| 3.0 | 3.12 | 16:50:05.20 | 16:50:08.29 | 16:49:59.43 | 16:50:02.52 | ||
| 4.0 | 4.12 | 16:54:05.75 | 16:54:10.16 | 16:54:00.28 | 16:54:04.42 | ||
| Evening | 2.0 | 2.41 | 21:04:31.45 | 21:04:33.92 | 21:04:25.17 | 21:04:27.33 | 7.0s |
| 3.0 | 3.16 | 21:17:01.90 | 21:17:04.99 | 21:16:55.26 | 21:16:58.41 | ||
| 4.0 | 4.19 | 21:20:45.24 | 21:20:49.48 | 21:20:38.47 | 21:20:42.61 | ||
Figure 4
Graphical representation of puffing and touching events from the conducted experiment, recorded while the thermistor was turned off.
