# Real-Time Anomaly Detection in Cold Chain Transportation Using IoT Technology
## 2 Literature Review
### Iot Monitoring Systems
[70] evaluated the implementation of IoT technologies to monitor fruit and vegetables according to different environmental parameters (temperature, relative humidity, light intensity, and concentration of gas). The system implemented in this study sends a notification to personnel for timely necessary action. Despite this, the prototype system is in a fixed cold store, not moving transport. [PERSON] et al. [7] monitored the temperature, humidity and light intensity of meat and seafood products. The authors discussed implementing an alert system based on thresholds in their study, yet no technical information was presented on how alerting criteria was configured or how it was implemented, leaving it unclear if the proposed alerting system was device, application, or platform specific. [PERSON] et al. [62] discussed a theoretical framework for alerting based on a fog-computing architecture to handle the computation; however, the framework was not implemented in the research. [PERSON] et al. [45, 63] studied the transport conditions of holly and peach. According to the authors, the system provides an early warning for the need to take effective proactive measures and prevent unexpected quality loss, improve the quality control and transparency of fruit export chain. However, no further details as to how it was configured were provided. The novelty of this work is a trip detection system, of which one of its main benefits is to increase the sensors' battery lifespan. However, some studies have made efforts to ensure the battery consumption of the IoT system is kept to a minimum. [PERSON] et al. [67] discussed the development of a \"time-synchronizing\" algorithm to reduce the slot time that the slave nodes are connected to the Wi-Fi network. However, this conceptual framework \begin{table}
\begin{tabular}{l l l l l l l l} \hline \hline
**Authors** & **Year** & **Product** & **Parameters Monitored** & **Communication** & **Real-Time** & **Alerting** & **Tip** \\  & & & & & **Monitoring App** & **System** & **Detection** \\ \hline [PERSON] et al. [43] & 2020 & Shellfish & T, RH, O\({}_{2}\), CO\({}_{2}\) & Zigbee and GPRS & ✓ & ✗ & ✗ \\ [PERSON] et al. [60] & 2020 & Sweet Cherry & T, RH, O\({}_{2}\), CO\({}_{2}\), C\({}_{2}\)H\({}_{4}\) & USB & ✗ & ✗ & ✗ \\ [PERSON] et al. [67] & 2020 & Lattices & T & Wifi and GPRS & ✗ & ✗ & ✗ \\ [PERSON] et al. [68] & 2020 & Pumpkin and organges & T, RH & RFID, 3G/4G, WiFi, LoRa, NB-IoT & ✗ & ✗ & ✗ \\ [PERSON] et al. [69] & 2020 & Mast & T & Bluetooth & ✓ & ✗ & ✗ \\ [PERSON] et al. [70] & 2021 & Fruit and Vegetables & T, RH, LI, VOC, V & WiFi & ✓ & ✓ & ✗ \\ [PERSON] et al. [71] & 2021 & Garite scape & T, RH, VOC, V & 4G & ✓ & ✗ & ✗ \\ [PERSON] [72] & 2021 & Frits and vegetables & T, CFS & SG & ✗ & ✗ & ✗ \\ [PERSON] et al. & 2023 & Perishable and frozen products & T, RH, GPS & LTE-M & ✓ & ✓ & ✓ \\ \hline \hline \end{tabular}  
* T, Temperature; H, Humidity; V, Velocity; GPS, Global Positioning System; RH, Relative Humidity; CO\({}_{2}\), Carbon Dioxide; VOC, Volatile Organic Compound; LI, Light; O\({}_{2}\), Oxygen; C\({}_{2}\)H\({}_{4}\), Ethylene.  
\end{table} 
Table 1: _Cont._was not applied to real-world problems. [PERSON] et al. [69] also discussed the frequency of parameter recordings in their study to optimise battery life. According to the authors, if a constraint encoding a maximum allowed temperature for a specific delivery stage has been exceeded, the device will enter \"alert\" mode and the measurement frequency is increased. If four consecutive readings exceed this threshold, an event is logged to mark the current delivery stage as non-compliant, and the readings demonstrating this non-compliance are also stored. The battery-saving benefits trip detection delivers is due to the reduced monitoring recordings while the food products are not in a trip, which in turn extends the battery lifespan and reduces their respective environmental impacts. However, detecting vehicle motion also allows for the production of intelligent alerts.