{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:14:58Z","timestamp":1760145298890,"version":"build-2065373602"},"reference-count":58,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2024,6,30]],"date-time":"2024-06-30T00:00:00Z","timestamp":1719705600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT\/MCTES","award":["UIDB\/50008\/2020"],"award-info":[{"award-number":["UIDB\/50008\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Applied Sciences"],"abstract":"<jats:p>Food waste has gained increasing attention and debate, given its economic, environmental, social, and nutritional implications. One-third of food intended for human consumption is wasted. Although it is present at all stages of the food supply chain, it is in the final stages of consumption, such as households and food services, that the problem becomes most evident. This work builds on a previous study by the same authors, which identified computer vision as a suitable technology for identifying and quantifying food waste in institutional canteens. Based on this result, this paper describes the proposal and implementation process of a prototype demonstration. It is based on a Raspberry Pi 4 platform, a ResNet-50 model adapted with the Faster Region-Convolutional Neural Network (Faster R-CNN) model, and an algorithm for feature extracting. A specially built dataset was used to meet the challenge of detecting soup bowls and classifying waste in their consumption. A web application was developed to visualize the data collected, supporting decision making for more efficient food waste management. The prototype was subjected to validation and functional tests, and proved to be a viable, low-cost solution.<\/jats:p>","DOI":"10.3390\/app14135729","type":"journal-article","created":{"date-parts":[[2024,7,2]],"date-time":"2024-07-02T11:33:53Z","timestamp":1719920033000},"page":"5729","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Development of a Prototype Solution for Reducing Soup Waste in an Institutional Canteen"],"prefix":"10.3390","volume":"14","author":[{"given":"Ana","family":"Correia","sequence":"first","affiliation":[{"name":"Polytechnic Institute of Castelo Branco, Pedro Alvares Cabral Avenue, No. 12, 6000-084 Castelo Branco, Portugal"}]},{"given":"Clara","family":"Aidos","sequence":"additional","affiliation":[{"name":"Polytechnic Institute of Castelo Branco, Pedro Alvares Cabral Avenue, No. 12, 6000-084 Castelo Branco, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5830-3790","authenticated-orcid":false,"given":"Jo\u00e3o M. L. P.","family":"Caldeira","sequence":"additional","affiliation":[{"name":"Polytechnic Institute of Castelo Branco, Pedro Alvares Cabral Avenue, No. 12, 6000-084 Castelo Branco, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, Rua Marqu\u00eas d\u2019\u00c1vila e Bolama, 6201-001 Covilh\u00e3, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8057-5474","authenticated-orcid":false,"given":"Vasco N. G. J.","family":"Soares","sequence":"additional","affiliation":[{"name":"Polytechnic Institute of Castelo Branco, Pedro Alvares Cabral Avenue, No. 12, 6000-084 Castelo Branco, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, Rua Marqu\u00eas d\u2019\u00c1vila e Bolama, 6201-001 Covilh\u00e3, Portugal"},{"name":"AMA\u2014Ag\u00eancia para a Moderniza\u00e7\u00e3o Administrativa, Rua de Santa Marta, No. 55, 1150-294 Lisbon, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,30]]},"reference":[{"key":"ref_1","unstructured":"Gustavsson, J., Cederberg, C., Sonesson, U., van Otterdijk, R., and Meybeck, A. (2011). Global Food Losses and Food Waste: Extent, Causes and Prevention, Food and Agriculture Organisation of the United Nations."},{"key":"ref_2","unstructured":"Instituto Nacional de Estat\u00edstica (2022). Desperd\u00edcio Alimentar-Resultados e Perspetivas, Instituto Nacional de Estat\u00edstica."},{"key":"ref_3","unstructured":"Tribunal de Contas Europeu (2016). Relat\u00f3rio Especial-Luta Contra o Desperd\u00edcio Alimentar: Uma Oportunidade para a UE Melhorar a Efici\u00eancia dos Recursos na Cadeia de Abastecimento Alimentar, Tribunal de Contas Europeu."},{"key":"ref_4","unstructured":"United Nations (2023, October 05). Ensure Sustainable Consumption and Production Patterns. Available online: https:\/\/sdgs.un.org\/goals\/goal12."},{"key":"ref_5","unstructured":"Correia, A., Aidos, C., Caldeia, J.M.L.P., and Soares, V.N.G.J. Using Computer Vision for Reducing Food Waste in an Institutional Canteen, Waste, Submitted, pending review."},{"key":"ref_6","unstructured":"Raspberry Pi (2024, May 21). Available online: https:\/\/www.raspberrypi.com\/."},{"key":"ref_7","unstructured":"(2024, May 21). Enterprise Open Source and Linux|Ubuntu. Available online: https:\/\/ubuntu.com\/."},{"key":"ref_8","unstructured":"(2024, May 21). MySQL. Available online: https:\/\/www.mysql.com\/."},{"key":"ref_9","unstructured":"(2024, May 17). Docker Desktop: The #1 Containerization Tool for Developers|Docker. Available online: https:\/\/www.docker.com\/products\/docker-desktop\/."},{"key":"ref_10","unstructured":"(2024, May 21). Microsservi\u00e7os e o Impacto na Escalabilidade de Aplica\u00e7\u00f5es. Available online: https:\/\/imaginedone.com.br\/artigos\/inovacao-e-tecnologia\/microsservicos\/."},{"key":"ref_11","unstructured":"(2024, May 18). Canvas Select Plus microSD Card, A1, Class 10 UHS-I, 64GB to 512GB-Kingston Technology. Available online: https:\/\/www.kingston.com\/en\/memory-cards\/canvas-select-plus-microsd-card."},{"key":"ref_12","unstructured":"(2024, May 18). Buy a Raspberry Pi Camera Module 3\u2013Raspberry Pi. Available online: https:\/\/www.raspberrypi.com\/products\/camera-module-3\/."},{"key":"ref_13","unstructured":"(2024, May 18). Infrared Reflective Sensor-Waveshare Wiki. Available online: https:\/\/www.waveshare.com\/wiki\/Infrared_Reflective_Sensor."},{"key":"ref_14","unstructured":"(2024, May 09). Camera-Raspberry Pi Documentation. Available online: https:\/\/www.raspberrypi.com\/documentation\/accessories\/camera.html."},{"key":"ref_15","unstructured":"(2024, May 18). How to Use Dual Cameras on the Raspberry Pi 5|Tom\u2019s Hardware. Available online: https:\/\/www.tomshardware.com\/raspberry-pi\/how-to-use-dual-cameras-on-the-raspberry-pi-5."},{"key":"ref_16","unstructured":"(2024, May 18). Raspberry Pi hardware-Raspberry Pi Documentation. Available online: https:\/\/www.raspberrypi.com\/documentation\/computers\/raspberry-pi.html."},{"key":"ref_17","unstructured":"(2024, May 18). Raspberry Pi 5-gpiod vs. RPi.GPIO-Raspberry Pi Forums. Available online: https:\/\/forums.raspberrypi.com\/viewtopic.php?t=359742."},{"key":"ref_18","unstructured":"(2024, May 09). Using a IR Reflective Sensor-Raspberry Pi Forums. Available online: https:\/\/forums.raspberrypi.com\/viewtopic.php?t=181544."},{"key":"ref_19","unstructured":"(2024, May 18). 2. Basic Recipes\u2014Gpiozero 2.0.1 Documentation. Available online: https:\/\/gpiozero.readthedocs.io\/en\/stable\/recipes.html#pin-numbering."},{"key":"ref_20","unstructured":"(2024, May 18). Oracle VM VirtualBox. Available online: https:\/\/www.virtualbox.org\/."},{"key":"ref_21","unstructured":"Instituto Polit\u00e9cnico de Castelo Branco (2024, May 21). Available online: https:\/\/www.ipcb.pt\/."},{"key":"ref_22","unstructured":"(2024, May 15). Roboflow: Computer Vision Tools for Developers and Enterprises. Available online: https:\/\/roboflow.com\/."},{"key":"ref_23","unstructured":"(2024, June 04). Soup-Bowl-Dataset Dataset > Overview. Available online: https:\/\/universe.roboflow.com\/sopa\/soup-bowl-dataset."},{"key":"ref_24","unstructured":"G\u00e9ron, A. (2022). Hands-On Machine Learning with Scikit-Learn, Keras and TensorFlow: Concepts, Tools, and Techniques to Build Intelligent Systems, O\u2019Reilly Media. [3rd ed.]."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1186\/s40537-021-00444-8","article-title":"Review of deep learning: Concepts, CNN architectures, challenges, applications, future directions","volume":"8","author":"Alzubaidi","year":"2021","journal-title":"J. Big Data"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Maur\u00edcio, J., Domingues, I., and Bernardino, J. (2023). Comparing Vision Transformers and Convolutional Neural Networks for Image Classification: A Literature Review. Appl. Sci., 13.","DOI":"10.3390\/app13095521"},{"key":"ref_27","unstructured":"Ren, S., He, K., Girshick, R., and Sun, J. (2015). Faster R-CNN: Towards Real-Time Object Detection with Region Proposal Networks. arXiv, Available online: http:\/\/arxiv.org\/abs\/1506.01497."},{"key":"ref_28","unstructured":"Google Colab (2024, May 09). Available online: https:\/\/colab.research.google.com\/drive\/1thXa8nF65Iywbcbm4LaZ_KDD1bkIvi9O?usp=sharing."},{"key":"ref_29","unstructured":"(2024, May 09). sovit-123\/fasterrcnn-pytorch-training-pipeline: PyTorch Faster R-CNN Object Detection on Custom Dataset. Available online: https:\/\/github.com\/sovit-123\/fasterrcnn-pytorch-training-pipeline."},{"key":"ref_30","unstructured":"(2024, May 24). Personal Cloud Storage & File Sharing Platform-Google. Available online: https:\/\/www.google.com\/drive\/."},{"key":"ref_31","unstructured":"(2024, May 24). GitHub: Let\u2019s Build from Here \u00b7 GitHub. Available online: https:\/\/github.com\/."},{"key":"ref_32","unstructured":"(2024, May 21). Overfitting and Underfitting in Machine Learning|SuperAnnotate. Available online: https:\/\/www.superannotate.com\/blog\/overfitting-and-underfitting-in-machine-learning."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"022022","DOI":"10.1088\/1742-6596\/1168\/2\/022022","article-title":"An Overview of Overfitting and its Solutions","volume":"1168","author":"Ying","year":"2019","journal-title":"J. Phys. Conf. Ser."},{"key":"ref_34","unstructured":"(2024, May 21). What Is Average Precision in Object Detection & Localization Algorithms and How to Calculate It?|by Aqeel Anwar|Towards Data Science. Available online: https:\/\/towardsdatascience.com\/what-is-average-precision-in-object-detection-localization-algorithms-and-how-to-calculate-it-3f330efe697b."},{"key":"ref_35","unstructured":"(2024, May 21). mAP (Mean Average Precision) for Object Detection|by Jonathan Hui|Medium. Available online: https:\/\/jonathan-hui.medium.com\/map-mean-average-precision-for-object-detection-45c121a31173."},{"key":"ref_36","unstructured":"Mudivedu, V. (2024, January 18). What Is the Difference between Training Loss Validation Loss and Evaluation Loss. Medium. Available online: https:\/\/medium.com\/@penpencil.blr\/what-is-the-difference-between-training-loss-validation-loss-and-evaluation-loss-c169ddeccd59."},{"key":"ref_37","unstructured":"(2024, May 09). Raspberry Pi OS\u2013Raspberry Pi. Available online: https:\/\/www.raspberrypi.com\/software\/."},{"key":"ref_38","unstructured":"(2024, May 17). How to Use Picamera2 to Take Photos with Raspberry Pi|Tom\u2019s Hardware. Available online: https:\/\/www.tomshardware.com\/how-to\/use-picamera2-take-photos-with-raspberry-pi."},{"key":"ref_39","unstructured":"(2024, May 09). rpi-gpio-example\/example.c at master \u00b7 krinkinmu\/rpi-gpio-example. Available online: https:\/\/github.com\/krinkinmu\/rpi-gpio-example\/blob\/master\/example.c."},{"key":"ref_40","unstructured":"(2024, May 09). Paramiko-How to SSH and Transfer Files with Python|by Mokgadi Rasekgala|Medium. Available online: https:\/\/medium.com\/@keagileageek\/paramiko-how-to-ssh-and-file-transfers-with-python-75766179de73."},{"key":"ref_41","unstructured":"(2024, May 09). Python-How to Transfer a File to ssh Server in an ssh-Connection Made by Paramiko?-Stack Overflow. Available online: https:\/\/stackoverflow.com\/questions\/11499507\/how-to-transfer-a-file-to-ssh-server-in-an-ssh-connection-made-by-paramiko."},{"key":"ref_42","unstructured":"(2024, May 17). Python: Event Monitoring with Watchdogs|by Pravash|Medium. Available online: https:\/\/pravash-techie.medium.com\/python-event-monitoring-with-watchdogs-86125f946da6."},{"key":"ref_43","unstructured":"PyTorch (2023, December 29). PyTorch 2.1 Documentation. Available online: https:\/\/pytorch.org\/docs\/stable\/index.html."},{"key":"ref_44","unstructured":"(2024, May 17). NumPy-. Available online: https:\/\/numpy.org\/."},{"key":"ref_45","unstructured":"(2024, May 17). CV2-Master Guide OpenCV Made for Python Developers. Available online: https:\/\/konfuzio.com\/en\/cv2\/."},{"key":"ref_46","unstructured":"(2024, May 17). os\u2014Miscellaneous Operating System Interfaces\u2014Python 3.12.3 Documentation. Available online: https:\/\/docs.python.org\/3\/library\/os.html."},{"key":"ref_47","unstructured":"(2024, May 17). The Official YAML Web Site. Available online: https:\/\/yaml.org\/."},{"key":"ref_48","unstructured":"(2024, May 17). Matplotlib\u2014Visualization with Python. Available online: https:\/\/matplotlib.org\/."},{"key":"ref_49","unstructured":"(2024, May 17). Copy\u2014Shallow and Deep Copy Operations\u2014Python 3.12.3 Documentation. Available online: https:\/\/docs.python.org\/3\/library\/copy.html."},{"key":"ref_50","unstructured":"(2024, May 17). Math\u2014Mathematical Functions\u2014Python 3.12.3 Documentation. Available online: https:\/\/docs.python.org\/3\/library\/math.html."},{"key":"ref_51","unstructured":"(2024, May 21). Coding Gaussian Blur Operation in Python from Scratch|by Rohit Krishna|Medium|Medium. Available online: https:\/\/medium.com\/@rohit-krishna\/coding-gaussian-blur-operation-from-scratch-in-python-f5a9af0a0c0f."},{"key":"ref_52","unstructured":"(2024, May 21). Implementing the Hough Transform from Scratch|by Alberto Formaggio|Medium. Available online: https:\/\/medium.com\/@alb.formaggio\/implementing-the-hough-transform-from-scratch-09a56ba7316b."},{"key":"ref_53","unstructured":"(2024, May 17). Truncated Cone Volume Calculator. Available online: https:\/\/www.omnicalculator.com\/math\/truncated-cone-volume."},{"key":"ref_54","unstructured":"(2024, May 17). mysql-Official Image|Docker Hub. Available online: https:\/\/hub.docker.com\/_\/mysql."},{"key":"ref_55","unstructured":"(2024, May 21). Docker Hub Container Image Library|App Containerization. Available online: https:\/\/hub.docker.com\/."},{"key":"ref_56","unstructured":"(2024, May 21). Java|Oracle. Available online: https:\/\/www.java.com\/en\/."},{"key":"ref_57","unstructured":"(2024, May 17). Spring Boot. Available online: https:\/\/spring.io\/projects\/spring-boot."},{"key":"ref_58","unstructured":"(2024, May 17). 2. Service Discovery: Eureka Server. Available online: https:\/\/cloud.spring.io\/spring-cloud-netflix\/multi\/multi_spring-cloud-eureka-server.html."}],"container-title":["Applied Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-3417\/14\/13\/5729\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T15:08:23Z","timestamp":1760108903000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-3417\/14\/13\/5729"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,6,30]]},"references-count":58,"journal-issue":{"issue":"13","published-online":{"date-parts":[[2024,7]]}},"alternative-id":["app14135729"],"URL":"https:\/\/doi.org\/10.3390\/app14135729","relation":{},"ISSN":["2076-3417"],"issn-type":[{"type":"electronic","value":"2076-3417"}],"subject":[],"published":{"date-parts":[[2024,6,30]]}}}