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@article{188387,
        author = {Prince Rhomel V. Pillagara and Leo M. Ramos and Noel T. Florencondia},
        title = {Development of an IoT-Based Monitoring System Utilizing Macro- and Micro-Environmental Parameters in Onion Cold Storage},
        journal = {International Journal of Innovative Research in Technology},
        year = {2025},
        volume = {12},
        number = {7},
        pages = {3018-3023},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=188387},
        abstract = {Onion (Allium cepa L.) is a high-value crop in Nueva Ecija, Philippines, yet farmers continue to incur substantial postharvest losses due to inadequate storage monitoring. Conventional cold storage facilities typically measure only macro-environmental conditions, overlooking micro-environmental variations within onion stacks that can accelerate deterioration. This study developed and field-tested an Internet of Things (IoT)-based monitoring system for onion cold storage that simultaneously measures macro- and micro-environmental temperature and relative humidity.
A quantitative, descriptive–developmental design was employed, using the Rapid Prototyping model of the Systems Development Life Cycle (SDLC). The prototype comprised an ESP32 microcontroller, three DHT22 temperature–humidity sensors, a 5 V power supply, and an enclosure, with data acquisition, transmission, and visualization implemented via the Arduino IoT Cloud platform. Field testing was conducted in an operational cold storage facility in Nueva Ecija over three days, with measurements taken every 30 minutes. System readings were paired with industrial-grade reference instrument readings, and data were analyzed using SPSS, employing independent-samples t-tests at a 0.05 level of significance.
Results showed that the system provided stable real-time monitoring for both chamber-level and in-stack conditions. Statistical analysis indicated no significant difference between system and manual measurements for temperature and relative humidity, demonstrating the reliability of the prototype. Additionally, onions stored at temperatures below 0 °C exhibited visible freezing injury, consistent with postharvest literature. The findings suggest that the developed IoT-based system can support more precise environmental control, reduce postharvest losses, and potentially improve the profitability and resilience of onion farmers in Nueva Ecija.},
        keywords = {Internet of Things, onion cold storage, macro-environment, micro-environment, temperature, relative humidity, postharvest losses},
        month = {December},
        }