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Öğe Areal Change Detection and 3D Modeling of Mine Lakes Using High-Resolution Unmanned Aerial Vehicle Images(Springer Heidelberg, 2016) Yucel, Mehmet Ali; Turan, Recep YavuzThis study focuses on the Etili and Comakli open-pit coal mines, where mine lakes are most densely located within the Can Coal Basin (northwestern Turkey). The aim of our study was to create 3D terrain models of these mine lakes using high-resolution images from an unmanned aerial vehicle (UAV) and to quantify areal changes linked to anthropogenic and meteorological effects over the study period. In November 2014 and October 2015, a DJI F550 hexacopter was flown at elevations of 30-100 m, and images were acquired using a 12-megapixel camera. Nineteen flights were completed, with each flight acquiring between 109 and 554 images. 3D modeling of UAV images was carried out with Agisoft software, using the most common structure from motion algorithm. Its workflow, involving image matching, georeferencing, digital elevation modeling, orthomosaics, 3D point cloud, and 3D textured model creation, was used to generate our 3D terrain model for the mine lakes. Orthomosaics with 1-6 cm/pixel resolution were used to assess areal change in the mine lakes. Area was calculated using two different methods (digitization and classification) within the ArcGIS package; results of these two methods were compared. Our UAV study of open-pit mines rapidly and precisely determined changes in topography linked to anthropogenic and meteorological effects. It also proved to be an effective method of visualizing such effects over the short term.Öğe Change detection and visualization of acid mine lakes using time series satellite image data in geographic information systems (GIS): Can (Canakkale) County, NW Turkey(Springer, 2014) Yucel, Deniz Sanliyuksel; Yucel, Mehmet Ali; Baba, AlperCan, a county in the province of Canakkale, is one of the most prominent coal mining districts in Turkey. Many mining companies have been operating coal deposits for power generation and district heating in this region since 1980. Generally, small and medium-scale mining companies operate for short periods and abandon the operational land without providing any rehabilitation. Human intervention in the natural structure and topography of the earth surface causes large holes and deterioration in these areas. Artificial lakes occur because of surface discharge and underground leakage into abandoned open pit mines with high lignite sulfur content (0.21-14.36 wt %). Furthermore, these lakes gain acidic character due to acid generation from pyrite oxidation. Acid mine lakes are highly acidic (pH < 3.05) and have elevated concentrations of , Fe and some metals. The main objective of this study is to evaluate the environmental conditions and demonstrate the development of a monitoring system for their possible changes in the acid mine lakes of the open cast lignite mining area on a regional scale. For this purpose, the data received from remote sensing satellites were used. Areal change detection and perimeter changes of nine acid mine lakes caused by coal mining companies in Can from 1977 to 2011, were determined using Landsat, Quickbird and Worldview satellite images. As a case study, an area of 9 km(2) was chosen for the variety of acid mine lakes. Using GIS software, satellite images were analyzed in time series, borders of acid mine lakes were digitized and converted into vector data format. At this stage, prior to the digitization, in order to create contrast on the satellite images, stretch type and stretch values were changed. The areal and perimeter changes were computed and presented via tables and graphics. In addition, thematic maps of the acid mine lakes were created and visualized. The results show that the number of acid mine lakes increased and these caused environmental risks due to their hydrochemical properties and areal increments.Öğe Determining hydrochemical characteristics of mine lakes from abandoned coal mines and 3D modelling of them using unmanned aerial vehicle(Pamukkale Univ, 2017) Yucel, Deniz Sanliyuksel; Yucel, Mehmet AliThis study was undertaken with the aim of creating three dimensional (3D) models of mine lakes formed in abandoned coal mines of the Can coal basin using high resolution unmanned aerial vehicle (UAV) images, determining hydrochemical characterization and investigating environmental effects. In May 2014 a DJI F550 model hexacopter was flown at heights varying from 30-100 m above lakes and surroundings and images were obtained with a 12 mega pixel camera. During the image processing stage the Agisoft program was used and orthophoto of the lakes with resolution from 1-6 cm and 3D terrain models were created. The total area of the lakes calculated from UAV images was 298751 up Additionally water samples were taken from lakes and downstream rivers simultaneous to UAV studies. According to water pollution control regulation in Turkey, the mine lakes were very severely polluted with low pH and high concentrations of metals such as Al, Fe, Mn, Ni and Zn. The lakes were in the category of water not suitable for use under any circumstances. There is a very high possibility that if these lakes drain the water resources will be affected. As a result it is necessary to rehabilitate the mine lakes as soon as possible using the most appropriate method for the field.Öğe Displacement of the South Pole from 2006 to 2021: Role of sea ice and Antarctic surface temperature(Masaryk University, 2022) Pirti, Atınç; Yucel, Mehmet Ali; Hoşbaş, Ramazan GürselThe effect of global warming on the southern polar regions necessitates careful monitoring of glacier deformations and their movements, as well as an understanding of atmospheric physics. For this purpose, the yearly movements of UNAVCO stations-South Pole Station (AMU2) (winter-summer) and other stations in the South Pole region have been observed in this paper for about a fifteen-year period (2006–2021). In addition, the area differences of the Antarctic continent due to seasonal changes (winter-summer) between 1980 and 2021 were investigated in this study. Moreover, the height values of the stations on the Antarctic continent were observed seasonally. The subglacial lakes in the Antarctic continent cause the differences in the height values as a result of the seasonal changes. A decrease in sea ice of 0.91 million km2 for the winter season and 0.55 million km2 for the summer season during a 41-year period has been determined for four sectors of the Antarctic continent. The temperature changes on the Antarctic continent in the summer and winter seasons (2005–2022) were also evaluated in this paper. Air temperature increases was apparent especially in the Antarctic Peninsula, East Antarctic and West Antarctic coasts. The Weddell Sea and the Amundsen Sea regions have had the most sea ice loss, each with 1.24 million km2. On the other hand, it can be observed that the East Antarctic sector has expanded by 0.32 million km2 © 2022 EMUNI Press. All rights reserved.Öğe Examination of the Earthquake (Samos Island) in Izmir (30.10.2020) by Using Cors-Tr GNSS Observations and InSAR Data(Korean Society Of Civil Engineers-Ksce, 2023) Pirti, Atinc; Hosbas, Ramazan Gursel; Yucel, Mehmet AliIzmir, which is one of the biggest cities of Turkey and has the extensive tectonic features of the Western Anatolia region, has been struck in recent years due to its high seismic activity. In particular, the south of Izmir is one of the regions that has high seismic activity in the city, which is constrained by major fault zones. The earthquake of magnitude of a Mw 6.9 occurred 8 km north of Samos Island at a depth of 16 km on 30.10.2020, at 11:51:24 UTC (14:51:24 Local Time (LT)). It occurred on a 40-kilometer-long north-dipping normal fault zone in the Mediterranean between Greece's Samos Island and Turkey's Kusadasi Bay. Following the mainschock, a tsunami with a height of more than 1 meter occurred at Sigacik Bay, south of Izmir, and on the north side of Samos Island. This article focuses on the investigation of the Samos earthquake by utilizing both GNSS data and InSAR images, and the obtained results are given in this paper. GNSS data were processed by using CSRS-PPP Software as static and kinematic modes. After processing the GNSS data, the maximum displacements were observed at CESME and IZMIR CORS-TR points located in the north of the fault. Horizontal movements of 12 cm and 6 cm towards the north were obtained at CESME and IZMIR points, respectively. However, the amount of horizontal movements was less at DIDIM and AYDIN CORS-TR locations, which are located to the south of the fault. In addition to GNSS data, ESA Sentinel-1 SAR data was used in the InSAR procedure, and the displacements were clarified using the unwrapped interferogram. The interferogram revealed a 10 cm uplift in the west of the Island of Samos and a 10 cm subsidence in the Izmir region, on the north side of the fault, based on the InSAR data. The most striking feature of this study is that the earthquake that occurred near the island of Samos was reported by Gansas' study that the 3 GNSS points (SAMO, SAMU, and 093A) on the island of Samos are moving in a south direction and the largest displacement is about 36 centimetres south. However, in our study, the north direction is more prominent as the direction of movement at IZMIR and CESME points. The movement at the DIDIM point supports his work. In other words, the Samos Fault affected the points located in the north and south differently.Öğe Geophysical investigations at Agadere Cemetery, Gallipoli Peninsular, NW Turkey(Taylor & Francis Ltd, 2014) Buyuksarac, Aydin; Yalciner, Cahit Caglar; Ekinci, Yunus Levent; Demirci, Alper; Yucel, Mehmet AliHistorical cemeteries are challenging targets for geophysical prospection but some non-destructive imaging techniques may be successful for mapping buried cemeteries if applied appropriately. Ground-Penetrating-Radar (GPR) has generally been considered to be the only geophysical method for determining cemeteries; however, Electrical-Resistivity-Tomography (ERT) and Magnetic-Imaging (MI), may determine geophysical traces of such cemeteries. Thus, as a first attempt at applying geophysical methods in the cemetery area of the Gallipoli Peninsula, these techniques were used to explore the buried graves at Agadere Cemetery. In this study, measured apparent resistivity data were processed using a two-dimensional (2D) tomographic inversion scheme. Resultant resistivity depth slices and volumetric resistivity images clearly showed the anomaly zone, which may be attributed to anthropogenic burials. Additionally, three-dimensional (3D) visualization of GPR results indicated some anomalies, much like the resistivity anomalies in terms of location. MI data were processed using linear transformations and an analytic signal image map presented anomaly zones located in some parts of the area, which are in agreement with those obtained by ERT and GPR surveys. Results derived from data processing techniques showed that these methods are suitable for bordering the locations of other buried historical graves in areas that have the same geological environment in the Peninsula.Öğe Hydrochemistry and Environmental Impacts of Kestanbol Geothermal Fluid(Tmmob Jeoloji Muhendisleri Odasi, 2020) Marmara, Harika; Yucel, Deniz Sanliyuksel; Özden, Süha; Yucel, Mehmet AliKestanbol geothermal field, located in the ancient town of Alexandria Troas, is at the contact between plutonic intrusions and neighboring metamorphic rocks in the Biga Peninsula. This area is also controlled by an ENE-WSW striking right lateral strike-slip fault segment representing the extension of the southern branch of the North Anatolian Fault to the west and is one of the geothermal fields with highest temperature in the Biga Peninsula. Kestanbol geothermal fluid from a well is used to heat facilities for thermal tourism and balneological purposes. The geothermal fluid continuously seeps into the environment with low flow rate and additionally, wastewater from the facility is discharged into Ilica stream. This study was conducted to determine the hydrochemical characteristics of the well and springs located in Kestanbol geothermal field and to evaluate the environmental effects of geothermal fluids on the soil and stream sediment. The temperature, electrical conductivity (EC) and pH of Kestanbol geothermal fluids are 59.5-74.1 degrees C, 30.3-35.5 mS/cm, and 6.45-6.71, respectively. The geothermal fluids are NaCl water type, with mean NaCl concentration of 19511 mg/L. In addition to higher EC values, and total dissolved solid content, Na+, Cl-, B, Ba, Fe and Mn concentrations of the Kestanbol geothermal fluid are above the tolerance limit of TS 266. Moreover, the geothermal fluid is heavily polluted water (class IV) according to the Turkish Inland Water Quality Regulations in terms of EC, Na+, Cl-, B and Fe. There is a scaling problem in the Kestanbol geothermal field. XRD and SEM-EDX analyses identified the minerals causing scale as calcite, halite and siderite. Arsenic, Fe and Mn concentration of scale, soil and stream sediment samples are higher than the mean value of world continental crust. According to the enrichment factor and geoaccumulation index, the geothermal fluid with intense rock interaction enriches soil and stream sediment in terms of As and Mn metal(loid)s as a result of discharge. It is recommended that geothermal fluids and waste waters from the facility should not be discharged into the soil and Ilica stream.Öğe Investigation of the earthquake (Michoacan-Colima) in Mexica (19.09.2022) by using GNSS stations and INSAR observations(Inst Geology & Geography, 2024) Pirti, Atinc; Yucel, Mehmet AliThe North American Plate is subducted under the Cocos and Rivera plates, while the Pacific Plate divides from the North American Plate near the spreading centre of the Baja California Gulf, placing the Mexican Republic in a seismically active area of the world. The earthquake of a magnitude of Mw 7.6-7.7 occurred 37 km southeast of the town of Aquila (near the municipality of Coalcoman) at a depth of 15.1 km on 19.09.2022 at 18:05:06 UTC (13:05:06 local time (LT)). This study focuses on the use of GNSS (Global Navigation Satellite System) data to investigate the Mexican earthquake, and the results (using static-kinematic methods) are presented in this paper. The TNCC and COL2 IGS stations, which are situated to the north and northwest of the fault, recorded the largest displacements after GNSS data processing. At five points, 9-25 cm horizontal motions were obtained in the southwest, northwest, and west directions. The quantity of horizontal motions, however, was smaller in the south of the fault stations UCOE (approximately 9-10 cm) and PENA from the COMET-LiCSAR analysis showed that the GNSS and InSAR solution mirrors the pattern of earthquakes. The GNSS and InSAR data were aligned by standardizing to a common spatial and temporal grid, with corrections for atmospheric delays and noise. The mirroring of patterns was evaluated by using correlaconsidered to validate the alignment and highlight any discrepancies.Öğe Investigation of the Mw 7.3 earthquake in Tonga Islands, Pacific Ocean, 11 November 2022(Inst Geology & Geography, 2024) Pirti, Atinc; Yucel, Mehmet Ali; Hosbas, Ramazan GurselThe Mw 7.3 Tonga earthquake occurred on 11 November 2022 at 19 degrees.288 S and 172 degrees.147 W. It was caused by reverse faulting in the outer rise of the Pacific Plate, about 75 km east of the Tonga Trench. We studied the Tonga earthquake on 11 November 2022 in order to detect a violent eruption of the Tonga submarine volcano in the South Pacific. Submarine volcano eruptions can displace seawater in a number of different ways, potentially triggering tsunamis. The Tonga subduction zone has the highest rate of plate convergence on Earth. It is one of the places with the most earthquakes. However, the recorded thrust events that can be placed with certainty on the plate boundary haven't been stronger than M 8.0, and the area's history suggests that there isn't much seismic coupling along the arc. The modelling of this earthquake based on the assumption that the fault plane dips to the west give dimensions of about 50 x 35 km, with most of the distance down -dipping from the hypocenter. In our study, we used the CSRS-PPP software to process TONGA station data using static and kinematic methods. This study shows the horizontal coordinate differences of the TONGA station (static -kinematic), which range from a few millimetres to about 40 centimetres.Öğe Monitoring of Icelandic plate movement with GNSS method and GPS signal jamming effects in Iceland(Sciendo, 2023) Pirti, Atinc; Hosbas, Ramazan Gursel; Yucel, Mehmet AliJamming is electromagnetic radiation or reflection that impairs the function of electronic instruments and equipment or communication tools. Intentionally disrupting or interfering with GPS signals, which are used for positioning, navigation, and timing, known as GPS jamming, is accomplished using a radio frequency emitting device. On January 8, 2022 (the day of a NATO exercise), it was investigated how GPS signal jamming affected the position accuracy at three IGS points in Iceland. The obtained coordinate differences between kinematic processing and static processing reached values of about 0.5-10 meters for the MAYV, and HOFN stations in this study. In addition to GPS signal jamming effect in Iceland, horizontal and vertical velocity fields of the three IGS stations in Iceland covering a twenty-two year period (2000-2022) in this study. According to the obtained results, a motion of about 2cm-2.5cm per year (horizontal) and 0.1cm-2.1cm per year (vertical) was computed at the three IGS stations (HOFN, REYK, and MAYV) located in Iceland.Öğe Spatial multi-criteria decision analysis for site selection of wind power plants: a case study(Taylor & Francis Inc, 2024) Can, Gokhan; Kocabaldir, Canan; Yucel, Mehmet AliSite selection for wind power plant (WPP) installation is a complex process that includes not only technical requirements but also physical, economic, social, and environmental sanctions. This study was carried out to determine optimal sites for WPP installation within the borders of canakkale province using spatial multi-criteria decision analysis (MCDA). Within the scope of the study, sites with a high level of suitability where a WPP can be established were determined by the geographic information system (GIS) and the analytical hierarchy process (AHP). The results were examined in two ways: by excluding and not excluding forest areas. After creating the two separate suitability maps, the annual electrical power generation potential (GP) map of the study area was generated. The results show that for the case where the forest areas were excluded, 67.26% of the study area is restricted and 29.94% is highly suitable, and for the case where the forest areas were not excluded, 58.94% is restricted and 36.25% is highly suitable. The total GP value of the highly suitable sites is 104,061.61 GWh/year. When the locations of existing WPPs were examined for control purposes, it was seen that the majority of them were located inside the areas with high suitability and outside the non-installable areas, but some of them were established in forested areas.Öğe TESTING REAL TIME KINEMATIC GNSS (GPS AND GPS/GLONASS) METHODS IN OBSTRUCTED AND UNOBSTRUCTED SITES(Assoc Surveyors Slovenia, 2013) Pirti, Atinc; Yucel, Mehmet Ali; Gumus, KutalmisThis paper describes an experiment carried out with the GNSS RTK method to combine GPS and GLONASS measurements in obstructed and unobstructed sites. This study investigates the RTK achievable accuracy and repeatability under different satellite constellations and site conditions in Samatya (coastal area), Istanbul, Turkey. The RTK (GPS and GPS/GLONASS) measurement techniques are described and compared in terms of productivity and precision. Surveyed area, control and test points as well as the impact area of trees where the precision decreases are visualised using Autodesk LandXplorer Studio ProfessionalTM Software. These obtained results indicate that integrating RTK GPS system with GLONASS is favoured for surveying applications.Öğe TESTING THE EXCAVATOR PERFORMANCE (USING TOPCON 3D EXCAVATOR X63 SYSTEM) ESPECIALLY FOR NAVIGATION AND EARTHWORK(Vilnius Gediminas Technical University, 2023) Pirti, Atınç; Yazici, Muharrem; Yucel, Mehmet AliConstruction sites commonly utilize bulldozers, wheel loaders, excavators, scrapers, and graders. Among these, excavators are versatile hydraulic heavy-duty equipment operated by humans. They are employed for various tasks like digging, levelling the ground, transporting and dumping loads, as well as providing straight traction. However, certain hazardous environments, such as nuclear disasters or earthquakes, are not suitable for human on-site work. To enhance productivity, accuracy, and profitability in excavation projects, the adoption of 3D machine control is recommended. The Topcon 3D Excavator X63 System offers advanced and precise GNSS positioning technology, coupled with Hidromek with Assist and an intuitive software interface, to significantly improve excavation operations. In this study, the accuracy of the coordinates of the route followed by the Excavator was checked by using RTK GNSS method by using P1 reference point. While the differences obtained in horizontal coordinates are 2–2.5 cm and 4–6 cm in vertical coordinates. In addition, excavation calculations of the earthwork area were performed and checked with the number of bucket of the excavator. The differences obtained from the earthwork were calculated as 0.8 cubic meters for each bucket. © 2023 The Author(s). Published by Vilnius Gediminas Technical University.Öğe TRANSRAPID AND THE TRANSITION CURVE AS SINUSOID(Univ Osijek, Tech Fac, 2016) Pirti, Atinc; Yucel, Mehmet Ali; Ocalan, TaylanThe transition curves in the modern highway and railway construction are route elements equally crucial as alignment and curve (circular). In order to prevent a sudden change of the centrifugal force, the transition curve must be applied due to the impact of the motion in a sharp curve. Over the years the application of the clothoid has become widespread in many countries in the world. However, in this study, in order to eliminate the problems concerning the road dynamics, created by clothoid for vehicles at high speed, sinusoid is examined. The possibility of using sinusoid in defining transition curves during design of transportation facilities is analysed in this paper. Basic properties of sinusoid, their fundamental mathematical expression, calculation of point coordinates, driving-dynamic characteristics of sinusoid are described (especially for Transrapid using), and the function of change in curvature and lateral impact along the sinusoid is presented. Sinusoid is dealt with as ideal curvature diagram which has curve and superelevation ramp in the articles.
