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  <front>
    <journal-meta>
      <journal-title-group><journal-title>Energy Catalyst</journal-title></journal-title-group>
      <issn pub-type="epub">3103-9952</issn>
      <publisher><publisher-name>Caravel Press</publisher-name></publisher>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="doi">10.61552/EC.2025.003</article-id>
      <article-id pub-id-type="publisher-id">2025.003</article-id>
      <title-group><article-title>Machine Learning-Based Predictive Models for Indoor Air Quality and Thermal Comfort: Bridging Sensor Data and Human Perception in Healthcare Facilities</article-title></title-group>
    <contrib-group>
      <contrib contrib-type="author" corresp="yes">
        <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-6389-8108</contrib-id>
        <name><surname>Razak</surname><given-names>Tajul Rosli</given-names></name>
        <xref ref-type="aff" rid="aff1"/>
        <email>tajulrosli@uitm.edu.my</email>
      </contrib>
      <contrib contrib-type="author">
        <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-5798-4926</contrib-id>
        <name><surname>Ismail</surname><given-names>Mohammad Hafiz</given-names></name>
        <xref ref-type="aff" rid="aff2"/>
      </contrib>
      <contrib contrib-type="author">
        <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-0921-3283</contrib-id>
        <name><surname>Jarimi</surname><given-names>Hasila</given-names></name>
        <xref ref-type="aff" rid="aff3"/>
      </contrib>
      <contrib contrib-type="author">
        <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-0925-3998</contrib-id>
        <name><surname>Nadzir</surname><given-names>Mohd Shahrul Mohd</given-names></name>
        <xref ref-type="aff" rid="aff4"/>
      </contrib>
      <contrib contrib-type="author">
        <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-7761-8939</contrib-id>
        <name><surname>Zheng</surname><given-names>Tianhong</given-names></name>
        <xref ref-type="aff" rid="aff5"/>
      </contrib>
      <contrib contrib-type="author">
        <name><surname>Yanan</surname><given-names>Zhang</given-names></name>
        <xref ref-type="aff" rid="aff5"/>
      </contrib>
      <contrib contrib-type="author">
        <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-9100-3116</contrib-id>
        <name><surname>Ahmad</surname><given-names>Emy Zairah</given-names></name>
        <xref ref-type="aff" rid="aff6"/>
      </contrib>
      <contrib contrib-type="author">
        <name><surname>Syafiq</surname><given-names>Ubaidah</given-names></name>
        <xref ref-type="aff" rid="aff7"/>
      </contrib>
      <contrib contrib-type="author">
        <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-0097-9477</contrib-id>
        <name><surname>Ludin</surname><given-names>Norasikin Ahmad</given-names></name>
        <xref ref-type="aff" rid="aff7"/>
      </contrib>
      <contrib contrib-type="author">
        <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-1202-3651</contrib-id>
        <name><surname>Rahman</surname><given-names>Noor Muhamad Abd.</given-names></name>
        <xref ref-type="aff" rid="aff8"/>
      </contrib>
      <contrib contrib-type="author">
        <name><surname>Jamaludin</surname><given-names>Mohd Haikal</given-names></name>
        <xref ref-type="aff" rid="aff8"/>
      </contrib>
      <contrib contrib-type="author">
        <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-3911-0851</contrib-id>
        <name><surname>Riffat</surname><given-names>Saffa</given-names></name>
        <xref ref-type="aff" rid="aff5"/>
      </contrib>
      <aff id="aff1">Faculty of Computer and Mathematical Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Malaysia; Department of Architecture and Built Environment, The University of Nottingham, University Park, Nottingham, NG7 2RD, United Kingdom</aff>
      <aff id="aff2">Faculty of Computer and Mathematical Sciences, Universiti Teknologi MARA, 02600 Arau, Malaysia</aff>
      <aff id="aff3">Solar Energy Research Institute. The National University of Malaysia, 43600 Bangi Selangor, Malaysia; Department of Architecture and Built Environment, The University of Nottingham, University Park, Nottingham, NG7 2RD, United Kingdom</aff>
      <aff id="aff4">Department of Earth Sciences and Environment, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia</aff>
      <aff id="aff5">Department of Architecture and Built Environment, The University of Nottingham, University Park, Nottingham, NG7 2RD, United Kingdom</aff>
      <aff id="aff6">Faculty of Electrical Technology and Engineering, Universiti Teknikal Malaysia Melaka, Hang Tuah Jaya, 76100 Durian Tunggal Melaka, Malaysia</aff>
      <aff id="aff7">Solar Energy Research Institute. The National University of Malaysia, 43600 Bangi Selangor, Malaysia</aff>
      <aff id="aff8">Engineering Services Division, Ministry of Health Malaysia, 62590, Putrajaya, Malaysia</aff>
    </contrib-group>
      <pub-date publication-format="electronic" date-type="pub"><day>16</day><month>05</month><year>2025</year></pub-date>
      <volume>1</volume>
      <fpage>35</fpage>
      <lpage>53</lpage>
      <self-uri xlink:href="https://caravelpress.com/journals/ec/articles/2025.003"/>
      <history>
        <date date-type="received"><string-date>16 May 2025</string-date></date>
        <date date-type="rev-recd"><string-date>6 April 2025</string-date></date>
        <date date-type="accepted"><string-date>16 May 2025</string-date></date>
      </history>
      <permissions>
        <copyright-statement>© 2025 The Author(s). Published by Caravel Press.</copyright-statement>
        <copyright-year>2025</copyright-year>
        <license license-type="open-access" xlink:href="https://creativecommons.org/licenses/by/4.0/">
          <license-p>This is an open access article under the CC BY 4.0 licence.</license-p>
        </license>
      </permissions>
      <abstract><p>Poor indoor air quality (IAQ) and inadequate thermal comfort continue to challenge healthcare facilities in Malaysia, especially in rural areas where poor ventilation and high humidity are prevalent. These environmental stressors negatively impact patient outcomes, staff well-being, and operational efficiency. Existing solutions often overlook the integration of subjective human perception with objective sensor data, resulting in limited adaptability and responsiveness. This study introduces a datadriven, human-centric framework that combines environmental sensor measurements with user-reported comfort feedback to develop predictive models for IAQ and thermal comfort. A comprehensive machine learning pipeline was implemented using four algorithms—Random Forest (RF), XGBoost, Artificial Neural Network (ANN), and Support Vector Machine (SVM)—to model both continuous IAQ indicators and categorical thermal preferences. Experimental results show that Random Forest achieved the best overall performance, with the lowest root mean squared error (RMSE = 14.35) in regression and the highest classification accuracy (87.5%) in predicting thermal preference. Statistical validation confirmed that Random Forest and XGBoost performed similarly in regression, while Random Forest and SVM showed no significant differences in classification accuracy. These findings validate Random Forest as a robust and consistent model across both tasks. This study contributes a validated, AI-enhanced framework for intelligent environmental monitoring in healthcare settings, emphasizing the integration of subjective and objective data streams. The approach supports personalized, data-driven interventions and offers practical insights for facility managers, clinicians, and policymakers aiming to optimize indoor conditions. Future work will focus on scaling the dataset across diverse facilities and climates, enabling real-time deployment, and incorporating explainable AI techniques to enhance model transparency and stakeholder trust.</p></abstract>
      <kwd-group kwd-group-type="author">
        <kwd>Indoor air quality</kwd>
        <kwd>Thermal comfort</kwd>
        <kwd>Machine learning</kwd>
        <kwd>Predictive model</kwd>
        <kwd>Artificial intelligence</kwd>
      </kwd-group>
    </article-meta>
  </front>
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