The aim of this study is to assess the applicability of shear wave elastography (SWE) in the diag... more The aim of this study is to assess the applicability of shear wave elastography (SWE) in the diagnosis of chronic autoimmune thyroiditis (CAT) patients. The study group consisted of 50 patients with first-diagnosed CAT and 40 control subjects (CS). In all patients with CAT and CS, sonoelastographic measurements were made in both thyroid lobes. Optimal cut-off values were chosen to maximize the sum of sensitivity and specificity. Positive predictive value (PPV), negative predictive value (NPV), and accuracy values were also calculated. Quantitative elastographic analysis evaluated by SWE in CAT patients (2.56 +/- 0.30 m/s) was significantly higher compared with CS (1.63 +/- 0.12 m/s) (p<0.001). The optimal cut-off value was 2.42 m/s. SWE had 77% sensitivity, 71% specificity, 92% PPV, 81% NPV, and 87% accuracy for the presence of CAT. Our data indicate that SWE correctly defines the elasticity of thyroid parenchyma, and this technique may assist in the diagnosis and treatment monit...
The objective of this study was to evaluate and predict land movement by integrating geodetic, ge... more The objective of this study was to evaluate and predict land movement by integrating geodetic, geophysical and meteorological data in a landslide area. Specifically, electrical resistivity tomography surveying, Global Navigation Satellite System and terrestrial laser scanning techniques were integrated to monitor a landslide. The study area lies to the southeast of the town of Taşkent in southern Turkey, close to Balcılar in the Central Taurus mountain chain. Landslides result in considerable damage to structures, farmland and the environment in this area; therefore, it is important to characterise the size, extent and timing of past land movements in order to mitigate damage from future landslides. Analysis presented in this paper shows that the greatest land movements in the region occur in spring, when average motions can be up to 1.5 m per month. It is demonstrated that integrated techniques provide a better means for monitoring landslide processes and gathering data for predictions of future movements. Mapping landslide movements by integrating geophysical and geodetic observations can provide a meaningful evaluation of a landslide and its dynamics.
2013 6th International Conference on Recent Advances in Space Technologies (RAST), 2013
ABSTRACT The advances in satellite technologies, image analysis techniques and computational powe... more ABSTRACT The advances in satellite technologies, image analysis techniques and computational power make possible processing huge amounts of high resolution images in real time. Acquiring high resolution images has a drawback, as the pixel resolution increases the surveyed area decreases. Multispectral scene is an image stack including numerous spectral bands from the electromagnetic wave spectrum, leading to richer spectral resolution. On the other hand, higher spatial resolution is included in the Panchromatic image. In order to have an image with higher spectral and spatial resolution, the applied merging process is called fusion. In this paper, fourteen different image fusion techniques were implemented. Serial implementations of all these approaches have longer execution time disadvantage compared to parallel approaches. To decrease execution time, the methods were modified with parallel computing approaches. This paper presents a comparison regarding speed performance of all fourteen methods&#39; serial and parallel implementations to increase pixel resolution and keep spatial resolution high by combining spectral and spatial information of high and low resolution images of the same co-registered region. Additionally, spectral quality assessments of methods are presented.
Konya Closed Basin that includes two depression blocks, Konya and Tuz Gölü, is the biggest endorh... more Konya Closed Basin that includes two depression blocks, Konya and Tuz Gölü, is the biggest endorheic basin in Turkey. A lowering in the ground levels of the depositional areas has been shown with respect to the surrounding mountains. In the past, this process was controlled by geological and hydrogeological phenomena; nowadays, it has gained a new dimension due to the excessive pumping of groundwater to the Earth's surface. The geodetic techniques such as Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) reveal a considerable land subsidence resulting in the rate of 1-4 cm/year in Konya sub-basin. It seems that the calculated amounts are responsible for changing environmental conditions like seasonality. Both GPS and differential InSAR techniques verify these relatively small fluctuations in the subsidence development. Target districts that should be observed primarily are agricultural zones where groundwater is overused for irrigation and regions where human population density is high. The geocoded interferogram and vegetation index map verify the spatial relation between the subsidence and green areas. In this study, a project dealing with the investigation of the land subsidence occurrences and of their possible causes and consequences within a specific part of Konya Closed Basin is introduced.
The Dereköy landslide threatening the town of Dereköy, Konya, Turkey is investigated in order to ... more The Dereköy landslide threatening the town of Dereköy, Konya, Turkey is investigated in order to assess and manage the associated risk. Dereköy town, located 12 km west of Konya city center, which is the second largest city in central Anatolia, has been extending due to the demand for new settlement places in Konya for the last decade. As most of the town is situated on the slopes of Meram river valley, on which the slope movements are observed, the risk of landslide has been increasing due to these new settlements. In this study, the landslide risk in Dereköy is assessed by following the socalled decision analytical procedure. The risk is defined by multiplication of hazard and consequences of the hazard. The hazard, which is the probability of slope failure, is computed by using the first-order second-moment (FOSM) method. The possible consequences of a landslide in Dereköy are analyzed and their costs are assessed relative to each other. A decision tree for choosing among the possible alternatives for reducing the risk is constructed in order to manage the risk.
IX ÖNSÖZ Devletin varlık nedenlerinden birisi toplumun asayiş ve güvenliğini sağlamaktır. Suçun h... more IX ÖNSÖZ Devletin varlık nedenlerinden birisi toplumun asayiş ve güvenliğini sağlamaktır. Suçun hiç olmadığı bir yer söz konusu olmamakla birlikte suçun en az oranda meydana geldiği yerler söz konusudur.
The aim of this study is to assess the applicability of shear wave elastography (SWE) in the diag... more The aim of this study is to assess the applicability of shear wave elastography (SWE) in the diagnosis of chronic autoimmune thyroiditis (CAT) patients. The study group consisted of 50 patients with first-diagnosed CAT and 40 control subjects (CS). In all patients with CAT and CS, sonoelastographic measurements were made in both thyroid lobes. Optimal cut-off values were chosen to maximize the sum of sensitivity and specificity. Positive predictive value (PPV), negative predictive value (NPV), and accuracy values were also calculated. Quantitative elastographic analysis evaluated by SWE in CAT patients (2.56 +/- 0.30 m/s) was significantly higher compared with CS (1.63 +/- 0.12 m/s) (p<0.001). The optimal cut-off value was 2.42 m/s. SWE had 77% sensitivity, 71% specificity, 92% PPV, 81% NPV, and 87% accuracy for the presence of CAT. Our data indicate that SWE correctly defines the elasticity of thyroid parenchyma, and this technique may assist in the diagnosis and treatment monit...
The objective of this study was to evaluate and predict land movement by integrating geodetic, ge... more The objective of this study was to evaluate and predict land movement by integrating geodetic, geophysical and meteorological data in a landslide area. Specifically, electrical resistivity tomography surveying, Global Navigation Satellite System and terrestrial laser scanning techniques were integrated to monitor a landslide. The study area lies to the southeast of the town of Taşkent in southern Turkey, close to Balcılar in the Central Taurus mountain chain. Landslides result in considerable damage to structures, farmland and the environment in this area; therefore, it is important to characterise the size, extent and timing of past land movements in order to mitigate damage from future landslides. Analysis presented in this paper shows that the greatest land movements in the region occur in spring, when average motions can be up to 1.5 m per month. It is demonstrated that integrated techniques provide a better means for monitoring landslide processes and gathering data for predictions of future movements. Mapping landslide movements by integrating geophysical and geodetic observations can provide a meaningful evaluation of a landslide and its dynamics.
2013 6th International Conference on Recent Advances in Space Technologies (RAST), 2013
ABSTRACT The advances in satellite technologies, image analysis techniques and computational powe... more ABSTRACT The advances in satellite technologies, image analysis techniques and computational power make possible processing huge amounts of high resolution images in real time. Acquiring high resolution images has a drawback, as the pixel resolution increases the surveyed area decreases. Multispectral scene is an image stack including numerous spectral bands from the electromagnetic wave spectrum, leading to richer spectral resolution. On the other hand, higher spatial resolution is included in the Panchromatic image. In order to have an image with higher spectral and spatial resolution, the applied merging process is called fusion. In this paper, fourteen different image fusion techniques were implemented. Serial implementations of all these approaches have longer execution time disadvantage compared to parallel approaches. To decrease execution time, the methods were modified with parallel computing approaches. This paper presents a comparison regarding speed performance of all fourteen methods&#39; serial and parallel implementations to increase pixel resolution and keep spatial resolution high by combining spectral and spatial information of high and low resolution images of the same co-registered region. Additionally, spectral quality assessments of methods are presented.
Konya Closed Basin that includes two depression blocks, Konya and Tuz Gölü, is the biggest endorh... more Konya Closed Basin that includes two depression blocks, Konya and Tuz Gölü, is the biggest endorheic basin in Turkey. A lowering in the ground levels of the depositional areas has been shown with respect to the surrounding mountains. In the past, this process was controlled by geological and hydrogeological phenomena; nowadays, it has gained a new dimension due to the excessive pumping of groundwater to the Earth's surface. The geodetic techniques such as Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) reveal a considerable land subsidence resulting in the rate of 1-4 cm/year in Konya sub-basin. It seems that the calculated amounts are responsible for changing environmental conditions like seasonality. Both GPS and differential InSAR techniques verify these relatively small fluctuations in the subsidence development. Target districts that should be observed primarily are agricultural zones where groundwater is overused for irrigation and regions where human population density is high. The geocoded interferogram and vegetation index map verify the spatial relation between the subsidence and green areas. In this study, a project dealing with the investigation of the land subsidence occurrences and of their possible causes and consequences within a specific part of Konya Closed Basin is introduced.
The Dereköy landslide threatening the town of Dereköy, Konya, Turkey is investigated in order to ... more The Dereköy landslide threatening the town of Dereköy, Konya, Turkey is investigated in order to assess and manage the associated risk. Dereköy town, located 12 km west of Konya city center, which is the second largest city in central Anatolia, has been extending due to the demand for new settlement places in Konya for the last decade. As most of the town is situated on the slopes of Meram river valley, on which the slope movements are observed, the risk of landslide has been increasing due to these new settlements. In this study, the landslide risk in Dereköy is assessed by following the socalled decision analytical procedure. The risk is defined by multiplication of hazard and consequences of the hazard. The hazard, which is the probability of slope failure, is computed by using the first-order second-moment (FOSM) method. The possible consequences of a landslide in Dereköy are analyzed and their costs are assessed relative to each other. A decision tree for choosing among the possible alternatives for reducing the risk is constructed in order to manage the risk.
IX ÖNSÖZ Devletin varlık nedenlerinden birisi toplumun asayiş ve güvenliğini sağlamaktır. Suçun h... more IX ÖNSÖZ Devletin varlık nedenlerinden birisi toplumun asayiş ve güvenliğini sağlamaktır. Suçun hiç olmadığı bir yer söz konusu olmamakla birlikte suçun en az oranda meydana geldiği yerler söz konusudur.
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