In the food industry, confusion stemming from expiration and date labels contributes to unnecessary food waste, underscoring the growing need for innovative food freshness sensors. This study presents a novel, cost-effective, and environmentally friendly dual-mode ammonia sensor tailored for real-time quality monitoring of protein-rich food products. Utilizing naturally occurring anthocyanin extracted from Clitoria ternatea (CT) and reinforced with polyvinyl alcohol (PVA) in a paper-based colorimetric system, the sensor demonstrates heightened sensitivity to ammonia gas, a key indicator of spoilage in protein-rich foods. Integration of a graphene nanoplatelets (GNPs) layer enables additional resistive gas sensing capabilities. The practicality and versatility of the fabricated sensor are enhanced by integrating near-field communication (NFC) technology, which facilitates batteryless and wireless sensing response transmission. The fabrication process of the sensor involves a straightforward, low-temperature solution route utilizing dip-coating and brush-coating methods. The incorporation of PVA significantly amplifies the colorimetric response, evidenced by a 44% increase in total color change compared to non-PVA reinforced sensors. This augmentation results in a more pronounced color change, which is readily discernible to the naked eye. The developed dual-mode sensor, equipped with NFC, is successfully applied to monitor shrimp freshness, demonstrating distinct color changes and NFC tag readability in response to ammonia release during spoilage. With its attributes of cost-effectiveness, environmental friendliness, simplicity, and wireless capabilities, this sensor offers a promising solution for widespread adoption in the food industry. This work contributes to advancing sensor technology, providing a versatile tool to ensure the quality and safety of perishable goods.
{"title":"Dual-Mode Batteryless Ammonia Sensor Using Polyvinyl Alcohol-Reinforced Clitoria ternatea Anthocyanin With Graphene Nanoplatelets for Enhanced Food Quality Monitoring","authors":"Thiresamary Kurian;Chun-Hui Tan;Pei-Song Chee;Vinod Ganesan","doi":"10.1109/JSEN.2024.3392954","DOIUrl":"10.1109/JSEN.2024.3392954","url":null,"abstract":"In the food industry, confusion stemming from expiration and date labels contributes to unnecessary food waste, underscoring the growing need for innovative food freshness sensors. This study presents a novel, cost-effective, and environmentally friendly dual-mode ammonia sensor tailored for real-time quality monitoring of protein-rich food products. Utilizing naturally occurring anthocyanin extracted from Clitoria ternatea (CT) and reinforced with polyvinyl alcohol (PVA) in a paper-based colorimetric system, the sensor demonstrates heightened sensitivity to ammonia gas, a key indicator of spoilage in protein-rich foods. Integration of a graphene nanoplatelets (GNPs) layer enables additional resistive gas sensing capabilities. The practicality and versatility of the fabricated sensor are enhanced by integrating near-field communication (NFC) technology, which facilitates batteryless and wireless sensing response transmission. The fabrication process of the sensor involves a straightforward, low-temperature solution route utilizing dip-coating and brush-coating methods. The incorporation of PVA significantly amplifies the colorimetric response, evidenced by a 44% increase in total color change compared to non-PVA reinforced sensors. This augmentation results in a more pronounced color change, which is readily discernible to the naked eye. The developed dual-mode sensor, equipped with NFC, is successfully applied to monitor shrimp freshness, demonstrating distinct color changes and NFC tag readability in response to ammonia release during spoilage. With its attributes of cost-effectiveness, environmental friendliness, simplicity, and wireless capabilities, this sensor offers a promising solution for widespread adoption in the food industry. This work contributes to advancing sensor technology, providing a versatile tool to ensure the quality and safety of perishable goods.","PeriodicalId":447,"journal":{"name":"IEEE Sensors Journal","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140827715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
To enhance the accuracy of object detection with event-based neuromorphic vision sensors, a novel event-based detector named spatiotemporal aggregation transformer (STAT) is proposed. First, in order to collect sufficient event information to estimate the problem considered, STAT uses a density-based adaptive sampling (DAS) module to sample continuous event stream into multiple groups adaptively. This module can determine the sampling termination condition by quantifying the velocity and size of objects. Second, STAT integrates a sparse event tensor (SET) to establish compatibility between event stream and traditional vision algorithms. SET maps events to a dense representation by end-to-end fitting the optimal mapping function, mitigating the loss of spatiotemporal information within the event stream. Finally, in order to enhance the features of slowly moving objects, a lightweight and efficient triaxial vision transformer (TVT) is designed for modeling global features and integrating historical motion information. Experimental evaluations on two benchmark datasets show that the performance of STAT achieves a mean average precision (mAP) of 68.2% and 49.9% on the Neuromorphic-Caltech101 (N-Caltech101) dataset and the Gen1 dataset, respectively. These results demonstrate that the detection accuracy of STAT outperforms the state-of-the-art methods by 2.0% on the Gen1 dataset. The code of this project is available at https://github.com/TJU-guozhaoxuan/STAT