Using Satellite Image Data For Detecting forest Burn Severity And evaulating Post-fire Temporal Status: Mediterrenean Region Sample

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2015Thesis (M.Sc.) -- İstanbul Technical University, Instıtute of Science and Technology, 2015Orman; ağaç, bitki ve çalıların geniş bir çevreye yayılarak oluştukları topluluğa verilen isimdir. Ormanı oluşturan sonsuz sayıdaki tüm madde ve olaylar birbirleriyle karşılıklı ilişki ve etkileşim halindedirler. Ormanlar sunmuş olduğu yararlar ile en önemli doğal kaynaklar arasında gelmektedirler. Ayrıca sosyal ve çevresel dengenin sağlanması konularında tüm ekosistem için son derece önemli bir yere sahiptirler. Orman yangınları etkileri ve doğurduğu sonuçlar itibarıyla tüm dünyada en önemli doğal afetlerin başında gelmektedir. İstatistiki veriler incelendiğinde orman yangınlarının ülkemizde değişken bir yapıda olduğu fakat son yıllarda nüfus artışına paralel olarak yangın sayısında belirgin bir artış olduğu gözlemlenmektedir. Bu durum; erozyon, heyelan, çölleşme, kütle kaybı ve doğal döngünün bozulmasına neden olmaktadır. Ayrıca, yangınlardan sonra zarar gören ormanların ve bitki örtüsünün yenilenmesi de arazi yönetimi açısından büyük önem arz etmektedir. Orman yangınlarının oluşum ve davranış özeliklerinin tahmin edilmesi yangınla mücadele çalışmaları açısından son derece önemlidir. Bu kapsamda, uydu görüntüleri kullanılarak, geniş alanlarda yangından etkilenen alanları ve yanma şiddetini  tespit etmek büyük kolaylık sağlamaktadır. Bu çalışmada, ülkemizde farklı tarihlerde Akdeniz Bölgesi’nde meydana gelen üç büyük orman yangını ele alınmıştır. Farklı uydu görüntüleri ve mekânsal otokorelasyon teknikleri birlikte kullanılarak yanan alan ve yanma şiddeti tespiti yapılmış ve yangın sonrası süreçte OGM (Orman Genel Müdürlüğü) tarafından yapılan orman rehabilitasyon çalışmalarının ne derecede fayda sapladığı belirlenmiştir. Bu kapsamda, ülkemizde yapılan çalışmalarının yeterli seviyede olmadığı görülmüştür. Bu tez çalışmasının amacı, ülkemizde bundan sonraki süreçte meydana gelebilecek orman yangınlarında, yanan alan tespiti ve yanma şiddetini uydu görüntüleri yardımıyla hızlı bir şekilde belirlemek ve yapılacak olan orman rehabilitasyon çalışmalarında yeşerme sürecini belirlemektir. Bu amaç doğrultusunda, Antalya-Taşağıl, Mersin-Gülnar ve Hatay-Samandağ orman yangınlarına ait yangın öncesi ve yangın sonrası Landsat 7 ETM+ ve MODIS Mod 09A (Surface Reflectance) görüntüleri kullanılarak, yanan alan ve yanma şiddeti tespiti normalize edilmiş yanma şiddeti ve fark normalize edilmiş yanma şiddeti indisleri kullanılarak belirlenmiştir. Daha sonraki süreçte, yanan alanlara ait çok zamanalı normalize edilmiş fark bitki örtüsü indisi görüntüleri elde edilmiş ve yapılan rehabilitasyon çalışmaları zamansal olarak incelenmiştir. Çalışma sonucunda, Antalya-Taşağıl yangını için MODIS dNBR görüntüsü sonucu 20 479 ha, Landsat 7 ETM + dNBR görüntüsü sonucu 16 996 ha, Landsat 7 ETM + lokal Moran’s I tekniği sonucu 12 212 ha, Landsat 7 ETM + Getis-Ord lokal Gi tekniği sonucu 15 242 ha yanan alan tespiti yapılmıştır ve yapılan orman rehabilitasyon çalışmalarının bölgenin büyük çoğunluğunda başarı sağladığı gözlemlenmiştir. Mersin-Gülnar yangını için MODIS dNBR görüntüsü sonucu 7812 ha, Landsat 7 ETM + dNBR görüntüsü sonucu 5388 ha, Landsat 7 ETM + lokal Moran’s I tekniği sonucu 4262 ha, Landsat 7 ETM + Getis-Ord lokal Gi tekniği sonucu 5271 ha yanan alan tespiti yapılmıştır ve yapılan orman rehabilitasyon çalışmalarının istenen sonucu tam olarak veremedeği ve yeşermenin zayıf kaldığı tespit edilmiştir. Hatay-Samandağ yangını için MODIS dNBR görüntüsü sonucu 1690 ha, Landsat 7 ETM + dNBR görüntüsü sonucu 1162 ha, Landsat 7 ETM + lokal Moran’s I tekniği sonucu 1045ha, Landsat 7 ETM + Getis-Ord lokal Gi tekniği sonucu 1074 ha yanan alan tespiti yapılmıştırve yapılan orman rehabilitasyon çalışmalarının geçen iki yıllık süreçte kuzey ve güney bölümlerde fayda sağlamaya başladığı görülmüştürThe area consisting of various types of trees, bushes and plants is called forest. Forests are usually located near shores where they can meet their need of water more efficiently. Bringing numerous economic and social benefits, like a remedy to pollution, forests are a crucial natural resource. Forests are important for balancing our climate in general. Plants also play a crucial role in the purification of air. When breathing, they absorb carbon dioxide and release oxygen. They were the reason why life outside of water became possible in the first place. Plants and forests help to enrich our soil by recycling nutrients that are obtained from dead leaves and small animals on the forest floor. . Furthermore, they have a rather vital place in the ecosystem for the enviromental and social balance.  Effects of forest fires and implications are one of the most important natural disasters all over the world. There are three conditions that need to be present in order for a wildfire to burn, which firefighters refer to as the fire triangle: fuel, oxygen, and a heat source. Fuel is any flammable material surrounding a fire, including trees, grasses, brush, even homes.  The greater an area's fuel load, the more intense the fire. Air supplies the oxygen a fire needs to burn. Heat sources help spark the wildfire and bring fuel to temperatures hot enough to ignite. The prediction and forecasting of the fire caracteristics is fundamantel for fire fighting. When the statistical data analyzed it is observed that forest fires have shown variation, but in parallel to the population growth a number of forest fires has increased widely in recent years. This causes erosions, landslides, desertification and mass loss. In addition, after forest fires, renewal of forests and vegetation crucial for land management. Classical methods used for detection of burned area and burn severity require a long and challenging process in terms of time and cost factors. Thanks to the advanced techniques used in the field of Remote Sensing, burned area and burn severity can be determined with high accuracy. Remote Sensing techniques usually use various spectral indexes which emphasize changes induced by fire in vegetation spectral behaviour to determine fire charecteristics precisely. Remote Sensing data can assist fire management as three stages relative to fire occurence :  (i) before the fire which related to vegetation biomass, (ii) during the fire which realted to near-real time location of fires, (iii) after the fire which related to assesment of burned areas. In this study, the three massive forest fires that occured in the Mediterannean district of our country have been observed. The pre-fire and post-fire continuum were sighted with the help of satallite images. Within this scope, by using satallite images, the burn severity was detected. Furthermore, rehabilitation studies were observed. In Turkey, it has not occured to one to put on a study on fire damage detection and burnt severity determination by using satallite images. The main purpose of this thesis, is to accurately and quickly  detect the burn area and  the burnt severty with the help of satallite images. In addition, a healthy observation of the foliation process of the rehabilitaion studies was aimed. In accordance with this purpose, the pre-fire and post-fire Landsat7 ETM + and MODIS Mod 09A (Surface Reflectance) satellite images and spatial autocorrelation statistics such as local Moran’s I and Getis-Ord local Gi indexes belonging to Antalya-Taşağıl, Mersin-Gülnar and Hatay-Samandağ were used together to detect the burned area and the burn ratio with the help of NBR (Normalized Burn Ratio) and dNBR (Differenced Normalized Burn Ratio) index.  In this study, 34 Landsat 7 ETM+ images and 6 MODIS Mod09A images used for evaluation of three forest fire period. Images for the initial assessment are taken directly before the fire (pre-fire image) and after the fire (post- fire image) as possible. The difference between those two images will show how much vegetation there was before the fire and how much was left after the burn thereby analyzing all the vegetation that was burned. Burn severity classification categories were divided into seven classes according to USGS (United States Geological Survey) standarts. Local Moran’s I and Getis-Ord Local Gi wee calculated using dNBR as intensity. In the following process, the NDVI (Normalized Difference Vegetation Index) images were obtained and the rehabilitation studies were observed temporally. In this context, NDVI images taken just before the fire started (pre-fire image) and are compared other NDVI images taken  after the fire (post-fire image) season until the year 2014. The spatial distribution of post-fire NDVI is mainly influenced by vegetation regeneration.  Satellite images have been used as an important source for identification of fire damages and risks in fire management field. This study was performed using pre-fire and post-fire satellite images to determine burned area, burn severity and post-fire regeneration in Mediterranean Region, Turkey where serious forest fires reoccurred.  In the end of the study, for  Antalya -Taşağıl fire, with using MODIS dNBR image 20 479 ha, Landsat 7 ETM + dNBR image 16 996 ha, Landsat 7 ETM + local Moran’s I technique 12 212 ha, Landsat 7 ETM + Getis-Ord local Gi technique 15 242 ha burned area results were detected. These results showed that, using Getis-Ord local Gi technique’s result  is the closest result to the General Directorate of Frorestry (GDF) datas. Forest rehabilitation works applied after fires, has been observed succesful  in the majority of the area. For Mersin-Gülnar fire, with using MODIS dNBR image 7812 ha, Landsat 7 ETM + dNBR image 5388 ha, Landsat 7 ETM + local Moran’s I technique 4262 ha, Landsat 7 ETM + Getis-Ord local Gi technique 5271 ha burned areas results were detected. These results showed that, using Getis-Ord local Gi technique’s result  is the closest result to the GDF datas for this fire, too. However, for this fire, forest rehabilitation works applied after fires, has been observed poor  germination, and rehabilitation works results has been discovered worse than expected. For Hatay-Samandağ  fire, with using MODIS dNBR  image 1690 ha,  germination Landsat 7 ETM + dNBR image 1162 ha, Landsat 7 ETM + local Moran’s I technique 1074 ha, Landsat 7 ETM + Getis-Ord local Gi technique 15 242 ha burned areas results were detected. These results showed that, using Getis-Ord local Gi technique’ s result  is the closest result to the GDF datas for this fire, too. In the last two-year period, rehabilitation works applied has been observed benefits in the northern and southern sections of forest.Yüksek LisansM.Sc

Semi-Automatic Building Extraction from WorldView-2 Imagery Using Taguchi Optimization

Due to the complex spectral and spatial structures of remotely sensed images, the delineation of land use/land cover classes using conventional approaches is a challenging task. This article tackles the problem of seeking optimal parameters of multi-resolution segmentation for a classification task using WorldView-2 imagery. Taguchi optimization was applied to search optimal parameters using the plateau objective function (&lt;small&gt;POF&lt;/small&gt;) and quality rate (&lt;small&gt;Qr&lt;/small&gt;) as fitness criteria. Analysis of variance was also used to estimate the contributions of the parameters for POF and Qr, separately. The scale parameter was the most effective one, with contribution levels of 87.45% and 56.87% for POF and Qr, respectively. Linear regression and support-vector regression methods were used to predict the results of the experiment. Test results revealed that Taguchi optimization was more effective than linear regression and support-vector regression for predicting POF and Qr values.</jats:p

Solution processed glass/fluorine-doped tin oxide/aluminum-doped zinc oxide double layer thin films for transparent heater and near-infrared reflecting applications

Double layer glass/fluorine-doped tin oxide (FTO)/aluminum-doped zinc oxide (AZO) multifunctional thin films were achieved via ultrasonic spray pyrolysis (USP) method without employing a post-deposition annealing. Transparent heater and near-infrared heat reflection behaviors were investigated. The samples were characterized in terms of their structural, morphological, optical, and electrical properties. The top AZO layer exhibited a polycrystalline structure without any preferred orientation. The double layer structure showed very high average transmittance (87%, 400-700 nm) in the visible and reflectance (55%, 2500 nm) in the near-infrared, regions. In addition, the sheet resistance and resistivity of the film were measured as 14.85 (Omega sq(-1)) and 1.78 x 10(-3) (Omega cm), respectively. The saturation temperature, response time, surface temperature uniformity, areal power density, and thermal resistance values were found to be 111 degrees C, 174 s, 11.42%, 0.299 W/cm(2), and 282.8 degrees C cm(2) W-1 for a sample with an active area of 31.5 cm(2) and input voltage of 9 V. In addition, dry-ice cooled samples (-25 degrees C) showed impressive deicing performance depending on the input power. In case of 12 V, all ice was defrosted, and water droplets were evaporated within 2 min and 10 s. During this process, a heating rate of similar to 43 degrees C/min was achieved

Solution processed aluminum-doped ZnO thin films for transparent heater applications

A study was carried out to tailor the properties of ultrasonic spray pyrolysis deposited Al-doped ZnO (AZO) thin films suitable for transparent heater applications. For this purpose, the influences of solvent/precursor type and molarity, Al-doping concentration, nozzle to substrate distance, solution flow rate, carrier gas flow, substrate temperature, and post-deposition annealing on the microstructure, electrical, optical properties, and heating/ deicing behaviors of the films were investigated. The optimized heaters were produced on 50 x 75 mm(2) glass substrates at 400 degrees C with 750 nm thickness and annealed under forming gas for 90 min. This sample revealed a good sheet resistance value of 38.7 Omega/square and 83% transmittance in the visible region. Heating/deicing tests showed that the maximum achievable surface temperature was 76 degrees C under an applied potential of 12 V and all ice/water can be removed completely within 250 s. In addition, the AZO heater exhibited a very high thermal resistance value (409 degrees C cm(2)/Watts) with stable and reversible heating behavior

Acute Renal Failure Secondary to Malignant Hypertension Induced Thrombotic Microangiopathy

The thrombotic microangiopathy (TMA) represents a discreet group of disorders with common pathological features including fibrinoid necrosis, endothelial cell injury, and obstruction of vessels.1 The clinical presentation ofTMA includes microangiopathic hemolytic anemia, thrombocytopenia, and functional impairment of various organ systems. Hemolytic uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP) are among the common causes of TMA. Patients with malignant hypertension are prone to TMA

Transmission of Hepatitis C Virus Infection to Spouses of Patients Undergoing Chronic Hemodialysis

Sexual transmission of HCV is relatively rare [1]. However, that anti-HCV measurements were performed with the first-generation tests in previous years may have led to having less evidence HCV transmitted sexually [2]. On the other hand, the prevalence of HCV infection in HD patients is quite high and the transmission of this infection to the patients is generally by way of blood transfusion and nosocomial [3], and the prevalence of HCV infection in HD patients in Turkey is reported as 49.4% in a multicenter study [4]. In this study, we investigated whether anti-HCV-positive HD patients transmitted this infection to their spouses sexually

Transmission of Hepatitis C Virus Infection to Spouses of Patients Undergoing Chronic Hemodialysis

Sexual transmission of HCV is relatively rare [1]. However, that anti-HCV measurements were performed with the first-generation tests in previous years may have led to having less evidence HCV transmitted sexually [2]. On the other hand, the prevalence of HCV infection in HD patients is quite high and the transmission of this infection to the patients is generally by way of blood transfusion and nosocomial [3], and the prevalence of HCV infection in HD patients in Turkey is reported as 49.4% in a multicenter study [4]. In this study, we investigated whether anti-HCV-positive HD patients transmitted this infection to their spouses sexually