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Öğe A GIS-based multi-criteria decision-making method for the selection of potential municipal solid waste disposal sites in Mersin, Turkey(Springer Science and Business Media Deutschland GmbH, 2022) Bilgilioğlu, Süleyman Sefa; Gezgin, Cemil; Orhan, Osman; Karakuş, PınarDue to rapid urbanization and the resulting rapid population increases, an important problem for cities today is the elimination of solid waste or finding suitable places for waste storage. Municipal solid waste disposal (MSWD) site selection is one of the most important steps in urban waste management. Many criteria political, economic, social, and technological should be considered in this process. Geographic information systems (GIS) and multi-criteria decision-making (MCDM) are tools that are superior to traditional methods in the planning phase of site selection studies. In this study, suitable MSWD sites were determined in Mersin (a Turkish province) based on GIS and the analytic hierarchy process, an MCDM method. Unsuitable areas in the study were removed at the beginning of the analysis. Eleven evaluation criteria were selected: elevation, slope, permeability, distance from lineaments, groundwater level, distance from rivers and water surfaces, distance from roads, distance from settlements, distance from protected areas, and land cover. Considering the evaluation and exclusion criteria, 19.12% of the study area was deemed suitable, and 80.88% was determined unsuitable for an MSWD site. An MSWD suitability map was created as a result of the study. The outcomes indicate that 80,377 ha and 83,022 ha of the study area were classified as high and very high suitability, respectively. Based on these results, we evaluate whether the locations of existing solid waste landfills are appropriate and propose alternative solid waste landfills for each district.Öğe A map Mash-Up application: Investigation the temporal effects of climate change on Salt Lake Basin(Copernicus Gesellschaft MBH, 2016) Kırtıloğlu, Osman Sami; Orhan, Osman; Ekercin, Semih; Halounova, L; Safar, V; Jiang, J; Olesovska, H; Dvoracek, P; Holland, D; Seredovich, VA; Muller, JP; Rao, EPR; Veenendaal, B; Mu, L; Zlatanova, S; Oberst, J; Yang, CP; Ban, Y; Stylianidis, S; Vozenlek, V; Vondrakova, A; Gartner, G; Remondino, F; Doytsher, Y; Percivall, G; Schreier, G; Dowman, I; Streilein, A; Ernst, JThe main purpose of this paper is to investigate climate change effects that have been occurred at the beginning of the twenty-first century at the Konya Closed Basin (KCB) located in the semi-arid central Anatolian region of Turkey and particularly in Salt Lake region where many major wetlands located in and situated in KCB and to share the analysis results online in a Web Geographical Information System (GIS) environment. 71 Landsat 5-TM, 7-ETM+ and 8-OLI images and meteorological data obtained from 10 meteorological stations have been used at the scope of this work. 56 of Landsat images have been used for extraction of Salt Lake surface area through multi-temporal Landsat imagery collected from 2000 to 2014 in Salt lake basin. 15 of Landsat images have been used to make thematic maps of Normalised Difference Vegetation Index (NDVI) in KCB, and 10 meteorological stations data has been used to generate the Standardized Precipitation Index (SPI), which was used in drought studies. For the purpose of visualizing and sharing the results, a Web GIS-like environment has been established by using Google Maps and its useful data storage and manipulating product Fusion Tables which are all Google's free of charge Web service elements. The infrastructure of web application includes HTML5, CSS3, JavaScript, Google Maps API V3 and Google Fusion Tables API technologies. These technologies make it possible to make effective "Map Mash-Ups" involving an embedded Google Map in a Web page, storing the spatial or tabular data in Fusion Tables and add this data as a map layer on embedded map. The analysing process and map mash-up application have been discussed in detail as the main sections of this paper.Öğe An Investigation of Volcanic Ground Deformation Using InSAR Observations at Tendürek Volcano (Turkey)(MDPI, 2023) Gündüz, Halil İbrahim; Yılmaztürk, Ferruh; Orhan, OsmanAlthough approximately one-tenth of the world’s population lives near volcanoes, most of the 1500 active volcanoes are not monitored by ground-based instruments because of the cost and difficulty of access. Since the development of interferometric synthetic aperture radar (InSAR) in the 1990s, recent advances have allowed the near-real-time detection of surface deformations, one of the earliest markers of volcanic activity. According to the Global Volcanism Program, Turkey’s most recent eruption (involving gas and ash) occurred in the Tendürek volcano in 1885. An explosion in the Tendürek volcano, which continues to actively output gas and steam, would be a critical issue for the life and property of the people living nearby. In this context, we processed the Sentinel-1 data collected by the European Space Agency using the Stanford Method for Persistent Scatterers, and the surface deformations of the Tendürek volcano were investigated. In addition, we applied two different atmospheric correction approaches (linear phase-based tropospheric correction and the Generic Atmospheric Correction Online Service for InSAR) to reduce atmospheric effects and found that the linear phase-based tropospheric correction model produced lower standard deviation values. Subsequently, the mean deformation velocity maps, displacement time series, and deformation components in the line-of-sight direction were calculated. The results showed that the most severe subsidence was ?11 mm/yr on the upper slopes of the Tendürek volcano. Although the lower slopes of the subsidence region have a lower settlement rate, the subsidence has a peak-caldera-centered location.Öğe Assessing and mapping landslide susceptibility using different machine learning methods(Taylor & Francis, 2022) Orhan, Osman; Bilgilioğlu, Süleyman Sefa; Kaya, Zehra; Özcan, Adem Kürşat; Bilgilioğlu, HacerThe main aim of the present study was to produce and compare landslide susceptibility maps by using five machine learning techniques, namely, artificial neural network (ANN), logistic regression (LR), support vector machine (SVM), random forest (RF) and, classification and regression tree (CART). The study area was determined as the Arhavi-Kabisre river basin, a region in which the most landslide incidents occur in Turkey. Firstly, a landslide inventory was produced by identifying a total of 252 landslides. Secondly, a total of 11 landslide conditioning factors were considered for the landslide susceptibility mapping. Subsequently, the five machine learning techniques were constructed with the help of the training dataset for the landslide susceptibility maps. Finally, the receiver operating characteristic (ROC), sensitivity, specificity, F-measure, accuracy and kappa index were applied to compare and validate the performance of the five machine learning techniques.Öğe Assessing and mapping landslide susceptibility using different machine learning methods(Taylor and Francis Ltd., 2020) Orhan, Osman; Bilgilioğlu, Süleyman Sefa; Kaya, Zehra; Özcan, Adem Kürşat; Bilgilioğlu, HacerThe main aim of the present study was to produce and compare landslide susceptibility maps by using five machine learning techniques, namely, artificial neural network (ANN), logistic regression (LR), support vector machine (SVM), random forest (RF) and, classification and regression tree (CART). The study area was determined as the Arhavi-Kabisre river basin, a region in which the most landslide incidents occur in Turkey. Firstly, a landslide inventory was produced by identifying a total of 252 landslides. Secondly, a total of 11 landslide conditioning factors were considered for the landslide susceptibility mapping. Subsequently, the five machine learning techniques were constructed with the help of the training dataset for the landslide susceptibility maps. Finally, the receiver operating characteristic (ROC), sensitivity, specificity, F-measure, accuracy and kappa index were applied to compare and validate the performance of the five machine learning techniques.Öğe Determination of recent tectonic deformations along the Tuz Gölü Fault Zone in Central Anatolia (Turkey) with GNSS observations(TUBITAK, 2022) Gezgin, Cemil; Ekercin, Semih; Tiryakioğlu, İbrahim; Aktuğ, Bahadır; Erdoğan, Hediye; Gürbüz, Esra; Orhan, Osman; Bilgilioğlu, Süleyman Sefa; Torun, Ahmet Tarık; Gündüz, Halil İbrahim; Oktar, Osman; Türkmen, Cezmi; Kaya, EfdalThe Tuz Gölü Fault Zone (TGFZ) is one of the most important active tectonic structures of Central Anatolia. The morphotectonic features of the TGFZ and the distribution of the epicenters of earthquakes over magnitude 5.0 show that this fault zone remains active today. In this study, the deformation of the TGFZ is determined with high sensitivity using geodetic measurements. To obtain accurate information about the deformation of the TGFZ, 24 GNSS sites and two continuously operating reference stations were constructed in the southern part of the TGFZ. Between 2018 and 2020, Global Navigation Satellite Systems (GNSS) measurements were made on this network. The data of the Turkish National Fundamental GPS Network (TNFGN) and the continuously operating reference stations-Turkey (CORS-TR) sites around the study area were also included in the study, and GNSS measurements were evaluated with the GAMIT/GLOBK software, and velocity fields of the region were determined. In addition, block modeling of the study area was calculated using the GeodSuit software. For the first time, slip rates provided by the geodetic network are established directly on the TGFZ segments, filling a significant deficiency in the literature, contributing to understanding the tectonics of the country and the region, and providing an important dataset for evaluating the degree of seismic activity of the fault zone. The slip rates obtained within the scope of this study are approximately 1.8 mm/yr strike-slip and 2 mm/yr dip-slip for the Acıpınar and Helvadere segments on that Aksaray city is built on. These results indicate that the active deformation in the TGFZ is greater than previously expressed compared to the slip rates calculated in previous studies.Öğe Investigation of Temporal Baseline Effect on DEMs Derived From COSMO Sky-Med Data(Murat YAKAR, 2021) Torun, Ahmet Tarık; Orhan, OsmanDigital elevation models (DEM) are indispensable elements of sensitive earth science studies. It is important the production and usage of DEMs. The science of remote sensing offers scientists an important source of data on this subject. Radar data, which is an active remote sensing system, has an important capacity in this regard. DEM production using InSAR data has been widely used in the literature in the last decade. The temporal baseline parameter, which is an important factor in data generation from InSAR pairs, also affects the final products. In this study, it is aimed to examine the usability of these data by producing short (4days), medium (84 days) and long (440 days) baseline DEMs using InSAR pairs of COSMO Sky-Med satellite. At the same time, photogrammetric DEMs were produced with unmanned aerial vehicles (UAV) in selected pilot areas. The DEMs produced were evaluated in 4 land surface types, namely plain-bare, agricultural, urban and rugged area. In addition, by performing statistical analyzes such as RMSE, MAE, the accuracy of the produced DEMs compared to the DEMs produced with UAV was examined. The results showed that short and medium baseline data give more accurate results than long baseline InSAR pairs. Increasing the temporal baseline, increases the amount of error in the DEMs produced. Also, the effect of land surface types on the produced DEMs was revealed in the results of the study.Öğe Konya Kapalı Havzası'nda uzaktan algılama ve CBS teknolojileri ile iklim değişikliği ve kuraklık analizi(Aksaray Üniversitesi Fen Bilimleri Enstitüsü, 2014) Orhan, Osman; Ekercin, SemihKonya Kapalı Havzası (KKH)'ndaki doğal kaynakların etkin ve sürdürülebilir bir şekilde kullanılmasını ve tarım faaliyetlerinde sürdürülebilirliği sağlamak amacıyla bu proje kapsamında; Landsat 5-TM görüntüleri yardımıyla 28 yıllık bir periyotta bölgenin yüzey sıcaklık, kuraklık haritaları oluşturulmuştur. Ek olarak havzadaki 10 adet meteorolojik istasyon ve yeraltı su seviye verileri kullanılarak Coğrafi Bilgi Sistemleri yardımıyla iklimsel değişimin bölgeye etkilerinin belirlenmesi amaçlanmıştır. Tez kapsamında 1984, 1989, 1998, 2003, 2007 ve 2011 yıllarına ait 29 adet Landsat-5 TM uydu görüntüsü temel veri kaynağı olarak kullanılmıştır. Bu uydu görüntüleri öncelikle geometrik ve radyometrik olarak düzeltilmiştir. Birbirleri ile karşılaştırılabilen hale gelen 5 tam çerçeve TM görüntüleri kullanılarak 6 yıla ait mozaik uydu görüntüleri elde edilmiştir. Daha sonra kuraklığın belirlenmesi için Arazi Yüzey Sıcaklığı (AYS), Sıcaklık-Bitki İndeksi (SBİ), Bitki Durum İndeksi (BDİ) Haritaları üretilmiş bunlara ek olarak Standart Yağış İndeks bilgileri de kullanılmıştır. Elde edilen sonuçlar, KKH'nda 1984 ve 2011 yılları arasında yüzey sıcaklık değerlerinin 2.00-3.00°C arasında yükseldiğini göstermektedir. BDİ'ne göre belli bölgelerde yaz kuraklığı etkisinde artış olmakta, SYİ'ne göre ise meteorolojik kuraklık belirli periyotlarla kendini göstermektedir. Bu olumsuz etkenlere ek olarak, bölgedeki yeraltı ve yerüstü su kaynaklarının plansız şekilde kullanımı ve bir yönetim planlamasının olmayışı, bölgenin en önemli problemi olarak görülmektedir.Öğe Use of Landsat land surface temperature and vegetation indices for monitoring drought in the Salt Lake Basin Area, Turkey(Hindawi Publishing Corporation, 2014) Orhan, Osman; Ekercin, Semih; Dadaşer Çelik, FilizThe main purpose of this paper is to investigate multitemporal land surface temperature (LST) changes by using satellite remote sensing data. The study included a real-time field work performed during the overpass of Landsat-5 satellite on 21/08/2011 over Salt Lake, Turkey. Normalized vegetation index (NDVI), vegetation condition index (VCI), and temperature vegetation index (TVX) were used for evaluating drought impact over the region between 1984 and 2011. In the image processing step, geometric and radiometric correction procedures were conducted to make satellite remote sensing data comparable with in situ measurements carried out using thermal infrared thermometer supported by hand-held GPS. The results showed that real-time ground and satellite remote sensing data were in good agreement with correlation coefficient (R-2) values of 0.90. The remotely sensed and treated satellite images and resulting thematic indices maps showed that dramatic land surface temperature changes occurred (about 2 degrees C) in the Salt Lake Basin area during the 28-year period (1984-2011). Analysis of air temperature data also showed increases at a rate of 1.5-2 degrees C during the same period. Intensification of irrigated agriculture particularly in the southern basin was also detected. The use of water supplies, especially groundwater, should be controlled considering particularly summer drought impacts on the basin.
