[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"doc-detail-124473-en":3,"doc-seo-124473-105":30,"detail-sidebar-cat-0-en-105":91},{"code":4,"msg":5,"data":6},0,"success",{"doc_id":7,"user_id":8,"nickname":9,"user_avatar":10,"doc_module":4,"category_id":11,"category_name":12,"doc_title":13,"doc_description":14,"doc_content":15,"file_id":16,"file_url":17,"file_type":18,"file_size":19,"view_count":4,"is_deleted":4,"is_public":20,"is_downloadable":20,"audit_status":20,"page_count":21,"language":22,"language_code":23,"site_id":24,"html_lang":23,"table_of_contents":25,"faqs":26,"seo_title":27,"seo_description":14,"update_tm":28,"read_time":29},124473,1099514068365,"Aurelia","https://ap-avatar.wpscdn.com/avatar/10000253d8d9f28188e?_k=1776742907772140068",8,"Research & Report","Long-term Continuous Monitoring of Dissolved Oxygen Concentration Based on Multispectral Sensors and Machine Learning","Dissolved oxygen is a key indicator of water quality that requires continuous observation across aquaculture, wastewater treatment, and environmental monitoring. Optical DO sensors are accurate but face practical barriers for long-term, large-scale use, including high deployment costs and periodic replacement of sensing probes due to degradation. This study proposes a non-contact system combining a low-cost multispectral sensor with an optimized machine learning pipeline. A compact spectroscopic unit collects absorbance over 18 wavebands (410–940 nm) and model-and waveband selection strategies identify four best bands (460, 585, 680, 760 nm) for neural network regression.","Long-term Continuous Monitoring of Dissolved Oxygen Concentration Based on Multispectral Sensors and Machine Learning  \nNhut-Thanh Tran1*, Chanh-Nghiem Nguyen1, Quoc-Hung Pham2,3, Chi-Ngon Nguyen1  \n1 Faculty of Automation Engineering, College of Engineering,  \nCan Tho University, Can Tho city, 94000, VIETNAM  \n2 Department of Computer Engineering, University of Information Technology, Ho Chi Minh city, 720400, VIETNAM  \n3 Vietnam National University, Ho Chi Minh city, 720400, VIETNAM  \n*[Corresponding Author: nhutthanh@ctu.edu.vn](Corresponding Author: nhutthanh@ctu.edu.vn)[ ](Corresponding Author: nhutthanh@ctu.edu.vn)DOI: [https://doi.org/10.30880/ijie.2025.17.09.006](https://doi.org/10.30880/ijie.2025.17.09.006)  \n\n| Article Info | Abstract |\n| --- | --- |\n| Received: 3 May 2025 | Dissolved oxygen (DO) is a crucial indicator of water quality and |\n| Accepted: 5 December 2025\u003Cbr>Available online: 31 December 2025 | requires continuous monitoring across various applications. Although optical sensors are widely used for DO measurement, their large-scale deployment for long-term monitoring remains challenging due to high |\n| Keywords\u003Cbr>Dissolved oxygen monitoring, multispectral sensor, machine learning, visible and near infrared spectroscopy | costs and the need for periodic replacement of sensing probes. This study presents a novel non-contact DO monitoring system that integrates a low-cost multispectral sensor with an optimized machine learning framework, offering a practical solution for long-term, continuous monitoring. A compact spectroscopic sensing unit was developed to continuously acquire absorbance data from water samples across 18 wavebands ranging from 410 to 940 nm. Multiple machine learning models were trained under different configurations, and several waveband selection algorithms were applied to identify the optimal predictive model. The neural network regression model utilizing four wavebands (460, 585, 680, and 760 nm) achieved the best result with a coefficient of determination and a root mean square error of 0.99 and 0.22 mg/L, respectively. These findings demonstrate the high accuracy and practical potential of the proposed system for longterm DO monitoring in aquaculture and environmental applications. |\n\n1. Introduction  \nDissolved oxygen (DO) is one of the important water quality indicators in many fields such as aquaculture, wastewater treatment, and environmental monitoring. For example, in aquaculture, changes in oxygen concentration in water can be achieved through major processes such as photosynthesis of aquatic plants, respiration of fish, shrimp, and other organisms, and diffusion of oxygen at the water surface [1] . The DO concentration must reach a suitable threshold for organisms to survive in an aquatic environment. Particularly, a DO concentration of 5 mg/L or higher is considered ideal. DO concentrations below 2 mg/L cause difficulties in development and even the risk of mass mortality [2]. Therefore, continuous monitoring and timely detection of DO deficiencies are essential for maintaining stable oxygen conditions and preventing adverse impacts [3].  \nThree main methods are commonly used to measure DO concentration: iodometric titration, electrochemical, and optical methods. Among these methods, iodometric titration is considered the most accurate and reliable [4] .  \nHowever, this is a complex and time-consuming chemical analysis method that is typically performed in a laboratory. This makes the iodometric titration method difficult to apply for continuous DO measurements in the field [4, 5]. The electrochemical method is widely used for many practical applications because of its fast, simple operation, and low cost. The main disadvantage of the electrochemical method is that the measurement device must be maintained and calibrated regularly. In addition, the measurement process of this method consumes oxygen from the measured water [4]. Therefore, this method is only suitable for ins","cbCaivHLHqfKXckV","https://ap.wps.com/l/cbCaivHLHqfKXckV","pdf",1059795,1,14,"English","en",105,"# Introduction\n## Importance of dissolved oxygen monitoring\n## Common DO measurement methods\n## Limitations for continuous long-term use\n## Motivation for non-contact absorption spectroscopy + machine learning","[{\"question\":\"Why is continuous dissolved oxygen monitoring important?\",\"answer\":\"Dissolved oxygen levels directly affect survival and growth of aquatic organisms. Monitoring helps detect deficiencies early and prevents adverse outcomes such as impaired development and mass mortality risks.\"},{\"question\":\"What challenges limit long-term deployment of optical dissolved oxygen sensors?\",\"answer\":\"Optical sensors can be costly and their probes typically require periodic replacement because the luminescent dye degrades over time, reducing measurement sensitivity.\"},{\"question\":\"How does the proposed system enable long-term non-contact DO monitoring?\",\"answer\":\"It uses a compact multispectral spectroscopic unit to acquire water absorbance across multiple wavebands without immersing sensing probes, then applies machine learning to predict DO.\"}]","Long-term Continuous Monitoring of Dissolved Oxygen Concentration Based on Multispectral Sensors and Machine Learning | PDF",1785822646,35,{"code":4,"msg":31,"data":32},"ok",{"site_id":24,"language":23,"slug":33,"title":13,"keywords":34,"description":14,"schema_data":35,"social_meta":86,"head_meta":88,"extra_data":90,"updated_unix":28},"long-term-continuous-monitoring-of-dissolved-oxygen-concentration-based-on-multispectral-sensors-and-machine-learning","",{"@graph":36,"@context":85},[37,54,68],{"@type":38,"itemListElement":39},"BreadcrumbList",[40,44,48,51],{"item":41,"name":42,"@type":43,"position":20},"https://docshare.wps.com","Home","ListItem",{"item":45,"name":46,"@type":43,"position":47},"https://docshare.wps.com/document/","Document",2,{"item":49,"name":12,"@type":43,"position":50},"https://docshare.wps.com/document/research-report/",3,{"item":52,"name":13,"@type":43,"position":53},"https://docshare.wps.com/document/long-term-continuous-monitoring-of-dissolved-oxygen-concentration-based-on-multispectral-sensors-and-machine-learning/124473/",4,{"url":52,"name":13,"@type":55,"author":56,"headline":13,"publisher":58,"fileFormat":61,"inLanguage":23,"description":14,"dateModified":62,"datePublished":62,"encodingFormat":61,"isAccessibleForFree":63,"interactionStatistic":64},"DigitalDocument",{"name":9,"@type":57},"Person",{"url":41,"name":59,"@type":60},"DocShare","Organization","application/pdf","2026-08-04",true,{"@type":65,"interactionType":66,"userInteractionCount":4},"InteractionCounter",{"@type":67},"ViewAction",{"@type":69,"mainEntity":70},"FAQPage",[71,77,81],{"name":72,"@type":73,"acceptedAnswer":74},"Why is continuous dissolved oxygen monitoring important?","Question",{"text":75,"@type":76},"Dissolved oxygen levels directly affect survival and growth of aquatic organisms. Monitoring helps detect deficiencies early and prevents adverse outcomes such as impaired development and mass mortality risks.","Answer",{"name":78,"@type":73,"acceptedAnswer":79},"What challenges limit long-term deployment of optical dissolved oxygen sensors?",{"text":80,"@type":76},"Optical sensors can be costly and their probes typically require periodic replacement because the luminescent dye degrades over time, reducing measurement sensitivity.",{"name":82,"@type":73,"acceptedAnswer":83},"How does the proposed system enable long-term non-contact DO monitoring?",{"text":84,"@type":76},"It uses a compact multispectral spectroscopic unit to acquire water absorbance across multiple wavebands without immersing sensing probes, then applies machine learning to predict DO.","https://schema.org",{"og:url":52,"og:type":87,"og:title":13,"og:site_name":59,"og:description":14},"article",{"robots":89,"canonical":52},"index,follow",{"doc_id":7,"site_id":24},{"code":4,"msg":5,"data":92},[93,97,101,105,110,115,120,123,128,131,135],{"id":20,"doc_module":4,"doc_module_name":46,"category_name":94,"show_sort_weight":95,"slug":96},"Story & Novel",90,"story-novel",{"id":47,"doc_module":4,"doc_module_name":46,"category_name":98,"show_sort_weight":99,"slug":100},"Literature",80,"literature",{"id":53,"doc_module":4,"doc_module_name":46,"category_name":102,"show_sort_weight":103,"slug":104},"Exam",70,"exam",{"id":106,"doc_module":4,"doc_module_name":46,"category_name":107,"show_sort_weight":108,"slug":109},5,"Comic",60,"comic",{"id":111,"doc_module":4,"doc_module_name":46,"category_name":112,"show_sort_weight":113,"slug":114},6,"Technology",50,"technology",{"id":116,"doc_module":4,"doc_module_name":46,"category_name":117,"show_sort_weight":118,"slug":119},7,"Healthcare",40,"healthcare",{"id":11,"doc_module":4,"doc_module_name":46,"category_name":12,"show_sort_weight":121,"slug":122},30,"research-report",{"id":124,"doc_module":4,"doc_module_name":46,"category_name":125,"show_sort_weight":126,"slug":127},9,"Religion & Spirituality",20,"religion-spirituality",{"id":126,"doc_module":4,"doc_module_name":46,"category_name":129,"show_sort_weight":126,"slug":130},"World Cup","world-cup",{"id":132,"doc_module":4,"doc_module_name":46,"category_name":133,"show_sort_weight":132,"slug":134},10,"Lifestyle","lifestyle",{"id":136,"doc_module":4,"doc_module_name":46,"category_name":137,"show_sort_weight":106,"slug":138},19,"General","general"]