{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,13]],"date-time":"2026-02-13T04:25:36Z","timestamp":1770956736325,"version":"3.50.1"},"reference-count":17,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,8,28]],"date-time":"2025-08-28T00:00:00Z","timestamp":1756339200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Portuguese Foundation for Science and Technology (FCT)","award":["SFRH\/BD\/149527\/2019"],"award-info":[{"award-number":["SFRH\/BD\/149527\/2019"]}]},{"name":"Portuguese Foundation for Science and Technology (FCT)","award":["ref: 7113"],"award-info":[{"award-number":["ref: 7113"]}]},{"name":"European Social Fund","award":["SFRH\/BD\/149527\/2019"],"award-info":[{"award-number":["SFRH\/BD\/149527\/2019"]}]},{"name":"European Social Fund","award":["ref: 7113"],"award-info":[{"award-number":["ref: 7113"]}]},{"name":"State Budget of the Portuguese Ministry of Education and Science","award":["SFRH\/BD\/149527\/2019"],"award-info":[{"award-number":["SFRH\/BD\/149527\/2019"]}]},{"name":"State Budget of the Portuguese Ministry of Education and Science","award":["ref: 7113"],"award-info":[{"award-number":["ref: 7113"]}]},{"name":"European Funds Next Generation EU","award":["SFRH\/BD\/149527\/2019"],"award-info":[{"award-number":["SFRH\/BD\/149527\/2019"]}]},{"name":"European Funds Next Generation EU","award":["ref: 7113"],"award-info":[{"award-number":["ref: 7113"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Cognitive Odor Source Localization (OSL) strategies are reliable search strategies for turbulent environments, where chemical cues are sparse and intermittent. These methods estimate a probabilistic belief over the source location using Bayesian inference and guide the searching movement by evaluating expected entropy reduction at candidate new positions. By maximizing expected information gain, agents make informed decisions rather than simply reacting to sensor readings. However, computing entropy reductions is computationally expensive, making real-time implementation challenging for resource-constrained platforms. Interestingly, search trajectories produced by cognitive algorithms often resemble those of small insects, suggesting that informative movement patterns might be replicated using simpler, bio-inspired searching strategies. This work investigates that possibility by analysing spatial distribution of entropy reductions across the entire search area. Rather than focusing on searching algorithms and local decisions, the analysis maps information gain over the full environment, identifying consistent high-gain regions that may serve as navigational cues. Results show that these regions often emerge near the source and along plume borders and that expected entropy reduction is strongly influenced by prior belief shape and sensor observations. This global perspective enables identification of spatial patterns and high-gain regions that remain hidden when analysis is restricted to local neighborhoods. These insights enable synthesis of hybrid search strategies that preserve cognitive effectiveness while significantly reducing computational cost.<\/jats:p>","DOI":"10.3390\/e27090909","type":"journal-article","created":{"date-parts":[[2025,8,28]],"date-time":"2025-08-28T10:29:18Z","timestamp":1756376958000},"page":"909","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Entropy Reduction Across Odor Fields"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0355-8662","authenticated-orcid":false,"given":"Hugo","family":"Magalh\u00e3es","sequence":"first","affiliation":[{"name":"Department of Electrical and Computer Engineering, Institute of Systems and Robotics, University of Coimbra, 3030-290 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9396-986X","authenticated-orcid":false,"given":"Lino","family":"Marques","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, Institute of Systems and Robotics, University of Coimbra, 3030-290 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Manjanna, S., Li, A.Q., Smith, R.N., Rekleitis, I., and Dudek, G. 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