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            <front>

                <journal-meta>
                                                                <journal-id>dubi̇ted</journal-id>
            <journal-title-group>
                                                                                    <journal-title>Duzce University Journal of Science and Technology</journal-title>
            </journal-title-group>
                                        <issn pub-type="epub">2148-2446</issn>
                                                                                            <publisher>
                    <publisher-name>Duzce University</publisher-name>
                </publisher>
                    </journal-meta>
                <article-meta>
                                        <article-id pub-id-type="doi">10.29130/dubited.1819498</article-id>
                                                                <article-categories>
                                            <subj-group  xml:lang="en">
                                                            <subject>Machine Learning Algorithms</subject>
                                                    </subj-group>
                                            <subj-group  xml:lang="tr">
                                                            <subject>Makine Öğrenmesi Algoritmaları</subject>
                                                    </subj-group>
                                    </article-categories>
                                                                                                                                                        <title-group>
                                                                                                                        <trans-title-group xml:lang="tr">
                                    <trans-title>Yüksek Yoğunluklu ve Çoklu Cihaz Ortamlarında Regresyon Tabanlı Koordinat Tahmini ile Wi-Fi İç Mekan Konumlandırmasının Performans Değerlendirmesi</trans-title>
                                </trans-title-group>
                                                                                                                                                                                                <article-title>Performance Evaluation of Wi-Fi Indoor Positioning by Regression-Based Coordinate Estimation in High-Density and Multi-Device Environments</article-title>
                                                                                                    </title-group>
            
                                                    <contrib-group content-type="authors">
                                                                        <contrib contrib-type="author">
                                                                    <contrib-id contrib-id-type="orcid">
                                        https://orcid.org/0000-0003-0541-0765</contrib-id>
                                                                <name>
                                    <surname>Üstebay</surname>
                                    <given-names>Serpil</given-names>
                                </name>
                                                                    <aff>ISTANBUL UNIVERSITY-CERRAHPASA</aff>
                                                            </contrib>
                                                                                </contrib-group>
                        
                                        <pub-date pub-type="pub" iso-8601-date="20260419">
                    <day>04</day>
                    <month>19</month>
                    <year>2026</year>
                </pub-date>
                                        <volume>14</volume>
                                        <issue>2</issue>
                                        <fpage>605</fpage>
                                        <lpage>616</lpage>
                        
                        <history>
                                    <date date-type="received" iso-8601-date="20251111">
                        <day>11</day>
                        <month>11</month>
                        <year>2025</year>
                    </date>
                                                    <date date-type="accepted" iso-8601-date="20260313">
                        <day>03</day>
                        <month>13</month>
                        <year>2026</year>
                    </date>
                            </history>
                                        <permissions>
                    <copyright-statement>Copyright © 2013, Duzce University Journal of Science and Technology</copyright-statement>
                    <copyright-year>2013</copyright-year>
                    <copyright-holder>Duzce University Journal of Science and Technology</copyright-holder>
                </permissions>
            
                                                                                                <trans-abstract xml:lang="tr">
                            <p>Günümüzde, kapalı bir alanda hareket eden nesnelerin konumunu belirlemek kritik bir ihtiyaç haline gelmiştir. Bu, hastanelerde hayati önem taşırken, müzelerde kültürel etkileşimi daha keyifli hale getirebilir. Hastaneler, alışveriş merkezleri, müzeler ve havaalanları dahil olmak üzere çeşitli kullanım senaryolarına hizmet eder. İnternetin ortaya çıkmasıyla birlikte, neredeyse her binada bulunan Wi-Fi erişim noktalarıyla konum tahmini en yaygın çözümlerden biri haline gelmiştir. Bu çalışma, Wi-Fi ve regresyon tabanlı yöntemlerin iç mekan konum problemlerindeki performansını incelemektedir. Gerçek bir test ortamında gerçekleştirilen deneylerde, XGBoost regresyonu hareketli nesnelerin konumlarını ortalama 1,4 m hata ile belirlemiştir. Ayrıca, test ortamındaki mobil cihazların donanım yapılarından kaynaklanan gürültülü sinyal ölçümlerinin konum sistemlerini nasıl etkileyebileceği incelenmiştir.</p></trans-abstract>
                                                                                                                                    <abstract><p>Determining the location of moving objects in indoor environments has become a crucial requirement for many application domains. While this could be vital in hospitals, it can also enhance cultural interaction in environments such as museums. It serves a variety of usage scenarios for shopping malls, museums, and airports. Fingerprinting-based location estimation, thanks to the widespread availability of Wi-Fi access points found in nearly every building, has become one of the most common solutions for indoor positioning. This study examines the performance of Wi-Fi RSSI–based regression methods for indoor localization. Using the TUJI1 multi-device dataset, six different regression models were evaluated under Euclidean distance–based performance metrics. Among these models, XGBoost regression determined the locations of moving objects with an average positioning error of 2.07 m on the test dataset and 2.04 m during training, outperforming other linear and nonlinear regression approaches. In addition, we investigated how noisy signal measurements originating from the hardware structures of different mobile devices in the test environment affect localization systems. To analyze device heterogeneity, multiple experimental scenarios were designed, including device-specific and unified models. The findings show that tree-based ensemble models provide robust and competitive performance without requiring complex deep learning architectures.</p></abstract>
                                                            
            
                                                                                        <kwd-group>
                                                    <kwd>Indoor positioning</kwd>
                                                    <kwd>  Wi-Fi RSSI fingerprinting</kwd>
                                                    <kwd>  Regression-based localization</kwd>
                                                    <kwd>  Device heterogeneity</kwd>
                                            </kwd-group>
                            
                                                <kwd-group xml:lang="tr">
                                                    <kwd>Kapalı alan konumlandırma</kwd>
                                                    <kwd>  Wi-Fi RSSI parmak izi</kwd>
                                                    <kwd>  Regresyon tabanlı konumlandırma</kwd>
                                            </kwd-group>
                                                                                                                                    <funding-group specific-use="FundRef">
                    <award-group>
                                                    <funding-source>
                                <named-content content-type="funder_name">This research received no external funding.</named-content>
                            </funding-source>
                                                                    </award-group>
                </funding-group>
                                </article-meta>
    </front>
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