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Aksaray, Turkey

Aksaray University is a public higher educational institution established on March 17, 2006 in Aksaray, Central Anatolia in Turkey. Formerly it was a subunit of the Niğde University.The university has four faculties, two institutes, two colleges and five vocational colleges. Its campus is located on the highway to Adana. Wikipedia.

Yalcin A.,Aksaray University
Applied Clay Science | Year: 2011

In the Trabzon province at the Eastern Black Sea region in Turkey, there are small and large landslides, especially following heavy rainfall periods in every year. These landslides regularly result in the loss of lives and properties. In this study, an assessment on the geotechnical characteristics of the areas where the landslides occur and the immediate vicinity were compared with the characteristics of non-landslides areas. A total of 50 landslides occurring in different locations were studied. As a result of the geotechnical investigations, the average of liquid limit values were between 49% and 69%, and the average plasticity index of the units ranged from 9% to 19% in the overlying materials in the landslide areas. Heavy rainfall exceeding boundary saturation of soils plays a critical role in causing landslides. According to the Unified Soil Classification System, the soils were "silts of high plasticity and silts, silty or clayey fine sands of low plasticity". 80% of the total landslides occurred within very high and completely weathered units of basalt, andesite, or pyroclastics, and intercalations of sandstone, clayey limestone and siltstone. This study shows that the shear strength parameters decreased with increasing moisture content and that the number of landslides increased in relation to the particle size distribution of the clay. © 2011 Elsevier B.V. Source

Sari M.,Aksaray University
Engineering Geology | Year: 2012

In this study, a special fitting technique is proposed to apply the Hoek-Brown failure criterion to available laboratory strength data collected on samples of Ankara andesites. The original method of fitting the Hoek-Brown failure criterion using the spreadsheet and the fitting method utilized in the RocLab software are statistically compared with this new modified nonlinear fitting technique. The Hoek-Brown failure parameters obtained by a simple multiple regression technique, utilizing the solver function within an Excel spreadsheet and the revised least squares procedure significantly improved the fitness of the Hoek-Brown envelope especially within the tensile and high confining stresses. The Brazilian tensile strength is found to be a useful parameter to fix a rock failure criterion at low confining stresses, particularly, in the tensile region. If tensile, uniaxial and triaxial test results are available, when compared to two existing fitting methods the modified multiple regression method is found to predict more precise tensile and compressive strengths, and material constant m i for the Hoek-Brown failure criterion. © 2011 Elsevier B.V. Source

Yilmazturk F.,Aksaray University
Optics Express | Year: 2011

In photogrammetric applications, camera calibration and orientation procedures are a prerequisite for the extraction of precise and reliable 3D metric information from images. This study presents a method for full automatic calibration of color digital cameras using color targets. Software developed using Borland C + + Builder programming language is used to apply the method. With this software, the calibration process is carried out in 3 stages: firstly, at least four of six color targets (whose 3D object coordinates are known) on each image of the overall test field are detected and the approximate exterior orientation parameters are computed. Then, the remaining target points are measured using the approximate image locations, determined using these parameters and the 3D object point coordinates parameters. Finally, calibration parameters are determined using a self-calibration bundle adjustment technique. The colored targets within the test field are assigned labels corresponding to their color. For the detection of color targets and computation of approximate exterior orientation elements, HSV color space was used together with space resection computation method for all the possible color labels of targets. To test the proposed method, full automatic calibration was carried out using six different digital cameras. The calibration accuracies achieved in object space were within the range 0.006 to 0.030 mm; the accuracies achieved in image space were within the range 0.14 to 0.51 μm. © 2011 Optical Society of America. Source

Kaya M.,Aksaray University
Applied Soft Computing Journal | Year: 2011

In this study, two new crossover operators in genetic algorithm are proposed; sequential and random mixed crossover. In the first stage, existing and developed crossover operators were applied to two benchmark problems, namely the reinforced concrete beam problem and the space truss problem. In the second stage, the developed crossover operators were applied to a deep beam problem and, a concrete mix design problem. The fittest values obtained using developed crossover operators were higher than those were obtained with existing crossover operator after 30,000 generations. Moreover, in developed crossover operators, the random mixed crossover yields higher fitness values than the existing crossover operators. © 2010 Elsevier B.V. All rights reserved. Source

Bayram F.,Aksaray University
Cold Regions Science and Technology | Year: 2012

Natural stones are generally used as building materials for construction and decoration. Determining the deteriorations of stones after freeze-thaw cycles is important subject for natural building stones used in cold regions exposed excessive freezing and thawing during the year. Freeze-thaw test is conducted for determining the deteriorations of stones due to freeze-thaw cycling. The percentage loss in uniaxial compression strength is an important parameter indicating these deteriorations. However, it is extremely laborious and time consuming tests. Because of this, predicting the percentage loss values in uniaxial compression strengths from intact rock properties was the purpose of this paper. Freeze-thaw tests were applied on nine limestone samples selected from different cold regions of Turkey. All of them except two samples were found to be suitable for use in cold regions. A statistical model was developed for predicting the percentage loss values in uniaxial compression strength from intact tests of impact strength, modulus of elasticity and water absorption. This model equation is very reliable (R 2=0.95) and can be very useful for predetermination of uniaxial compression strengths of limestones after freeze-thaw test without testing. © 2012 Elsevier B.V. Source

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