Kıyı izleme, doğal kaynakların yönetimi, çevresel planlama ile ilgili konularda hayati bir rol oynamaktadır. Kıyı alanlarında kıyı erozyonu, sediman taşınımı ve kıyı morfodinamiğinin değişimi sadece doğal etkenlerden değil aynı zamanda insan kaynaklı da olabilmektedir. Gelişen teknoloji ile insansız hava araçları lokal alanlarda hızlı, güvenilir veri toplama araçları olarak kullanılmaya başlanmıştır. Sunulan çalışmada Terkos bölgesi "Sürdürülebilir Kıyı Bölgesi İzleme Modeli İçin İnsansız Hava Araçları Entegrasyonu-Üç Boyutlu Otomatik Kıyı Ekstraksiyonu ve Analizi" başlıklı "TÜBİTAK Projesi (Proje No: 115Y718)" kapsamında üretilen ortofoto görüntü kullanılmıştır. GNSS ölçüleri ve elle sayısallaştırma sonuçları karşılaştırılarak insansız hava araçlarının, uluslararası standartlar çerçevesinde kıyı çizgilerinin belirlenmesindeki kullanım olanakları araştırılmıştır.

To investigate theperformance of low-cost GNSS equipment in monitoring horizontal displacements ANN-MB-GNSS and A10 antenna were installed on Zeiss-BRT-006 reduktionstachymeter, which can move with mm sensitivity in the horizontal plane. Ten days of static data were recorded with U-Blox-ZED-F9P-02B-GNSS receiver and processed with CSRS-PPP online-service. Considering theobservation period(12,6,3,1h), nine horizontal displacement magnitude tests were performed.Inaddition, GNSS-PPPAR solution percentages, multipath and signal-to-noise ratio values were considered. The results reveal that 20mm displacement can be determined (6mmRMSE) using the PPP approach based on a 3-hour observation period with A10antenna and 30mm can be determined (15mmRMSE) with UBX antenna with a 6-hour observation.

Satellite-based positioning, which started being developed in the mid-1960s for military purposes, is now used in almost every area. For the studies single and/or double frequency receivers are used. The cost of a receiver and antenna couple that have capable of high coordinate accuracies ranges from $3000 to $15000. With the production of Original Equipment Manufacturer (OEM) receivers, the cost of satellite-based location determination decreases to approximately one in 10 for the civilian user compared to the operations performed with geodetic receivers and antennas. However, although these receivers collect data in multi-Global Navigation Satellite System (GNSS) and frequencies, the accuracy of the coordinate values estimated is not as high as geodetic receivers and antennas. Therefore, it is necessary to carry out an accuracy study to obtain information about which studies can be used in. In this study, measurements were made at the UZEL point located on the roof of the Yıldız Technical University Geomatics Engineering Department by using the ZED-F9P-02B OEM multi GNSS receiver and ANN-MB L1/L2 multi-band GNSS patch antenna. The performance of the test results has been examined by comparing the results from CSRS(Canadian Spatial Reference System)-PPP with the coordinates of the UZEL point. As a result of the comparison, the difference between the coordinate determined with collected 3.5 hr data and the coordinates of the UZEL point has been determined as – 1.4 cm, 2.8 cm, and 9.3 cm in the East, North, and Height directions, respectively

Accurate and reliable positioning is a fundamental requirement for marine applications, particularly in hydrographic surveying, where real-time data acquisition is essential. Despite recent advances in Global Navigation Satellite System (GNSS) technologies, the comparative performance of different real-time correction strategies under marine conditions remains insufficiently addressed. This study presents a comparative performance analysis of three real-time GNSS positioning solutions—Precise Point Positioning–Real-Time Kinematic (PPP-RTK), Network RTK (NRTK), and Single-Baseline RTK (SBL-RTK) with Post-Processed Kinematic (PPK) coordinates adopted as the reference. Performance was assessed using statistical accuracy metrics in accordance with the International Hydrographic Organization (IHO) S-44 standards. At the 95% confidence level, the Total Horizontal Uncertainty (THU) values were 5.6 cm for PPP-RTK and 4.5 cm for NRTK, while the Total Vertical Uncertainty (TVU) values were 3.6 cm and 6.8 cm, respectively. Both NRTK and PPP-RTK solutions met IHO S-44 standards. Under the test conditions considered in this study, the SBL-RTK solution exhibited lower performance than the other solutions, mainly due to the higher proportion of float and stand-alone solution epochs. The findings indicate that the NRTK solution is suitable for near-shore hydrographic surveys where cellular connectivity is available. PPP-RTK represents a reliable alternative for marine applications through satellite-based correction services. This study contributes to the evaluation and selection of appropriate GNSS-based positioning strategies for hydrographic surveying.

1. Hydrographic surveying deals with the configuration of the bottom and neighboring land areas of oceans, lakes, rivers, harbors, and other water forms on Earth. The principal aim of most hydrogra...