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Gaziantep, Turkey

The Gaziantep University is a state research university located in Gaziantep, Southeastern Anatolia, Turkey. The university of Gaziantep has 10 faculties, containing a total of 22 academic departments, with a strong emphasis on scientific and technological research.Gaziantep is the largest trade and industrial center in the west of Southeastern Turkey. The University of Gaziantep was founded as a state university on 27 June 1987, but higher education on campus began in 1973 when the institute was an extension campus of the Middle East Technical University. The main campus is located at Gaziantep, which is close to the city centre, with its extension campuses situated in the neighbouring cities.The objectives of the university are:Cultural, scientific, technical, medical and vocational education and training,Fundamental and applied research,Technical, scientific and cultural exchanges with similar institutions at national and international levels,The University of Gaziantep enrolled 24,406 undergraduates, 482 postgraduate students, and employed 1,048 faculty members in the 2008/09 school year. The language of instruction at the Gaziantep University is English. Wikipedia.

Baysal E.,University of Gaziantep
European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery | Year: 2013

Chronic otitis media usually presents with a benign tumor-like lesion of the temporal bone known as a cholesteatoma. The role of oxidative stress in the pathogenesis of chronic otitis media and cholesteatoma has not yet been fully explored. Therefore, the aim of this study was to investigate the oxidative stress markers and antioxidant enzymes in patients with cholesteatomatous and noncholesteatomatous chronic otitis media and in healthy subjects. A prospective controlled trial was performed on cholesteatomatous and noncholesteatomatous chronic otitis media patients in a tertiary referral center in a university hospital. A total of 75 subjects, including 25 cholesteatomatous and 25 noncholesteatomatous chronic otitis media patients and 25 healthy subjects participated in this study. Serum total oxidant status (TOS) and oxidative stress index (OSI) levels were significantly increased in the patient groups with or without cholesteatoma compared with the control group. Serum total antioxidant status (TAS) levels and Paraoxonase and arylesterase activity were significantly lower in the patient groups with or without cholesteatoma compared with the control group. Serum TOS and OSI levels were lower in the noncholesteatomatous group, whereas serum TAS levels were higher compared with the cholesteatomatous group. Serum arylesterase activity was significantly lower in the noncholesteatomatous group compared with the control group. The results of this study reveal that in cholesteatoma cases, the oxidative stress and antioxidant enzyme imbalance were more significant than in cases of chronic otitis media without cholesteatoma.

Guneyisi E.M.,University of Gaziantep
Earthquake Engineering and Structural Dynamics | Year: 2012

The present paper investigates the seismic reliability of the application of buckling restrained braces (BRBs) for seismic retrofitting of steel moment resisting framed buildings through fragility analysis. Samples of regular three-storey and eight-storey steel moment resisting frames were designed with lateral stiffness insufficient to comply with the code drift limitations imposed for steel moment resisting frame systems in earthquake-prone regions. The frames were then retrofitted with concentrically chevron conventional braces and BRBs. To obtain robust estimators of the seismic reliability, a database including a wide range of natural earthquake ground motion records with markedly different characteristics was used in the fragility analysis. Nonlinear time history analyses were utilized to analyze the structures subjected to these earthquake records. The improvement of seismic reliability achieved through the use of conventional braces and BRBs was evaluated by comparing the fragility curves of the three-storey and eight-storey model frames before and after retrofits, considering the probabilities of four distinct damage states. Moreover, the feasibility of mitigating the seismic response of moment resisting steel structures by using conventional braces and BRBs was determined through seismic risk analysis. The results obtained indicate that both conventional braces and especially BRBs improve significantly the seismic behavior of the original building by increasing the median values of the structural fragility curves and reducing the probabilities of exceedance of each damage state. © 2011 John Wiley & Sons, Ltd.

Gullu H.,University of Gaziantep
Engineering Applications of Artificial Intelligence | Year: 2014

In order to understand the treatment of a marginal soil well, the underlying input-output relationship on the strength and elastic responses due to nonlinearity has always been a great importance in the stabilized mixtures for an optimal design. This paper employs a relatively new soft computing approach, genetic expression programming (GEP), to formulations for unconfined compressive strength (UCS) and elasticity modulus (Es) of clay stabilized with bottom ash, using a database obtained from the laboratory tests conducted in the study. The predictor variables included in the formulations are bottom ash dosage, dry unit weight, relative compaction, brittleness index and energy absorption capacity. The results demonstrate that the GEP-based formulas of UCS and Es are significantly able to predict the measured values to high degree of accuracy against the nonlinear behavior of soil (p<0.05, R>0.847). The GEP approach is found to have a better correlation performance as compared with the nonlinear regression as well. The sensitivity analysis for the parameter importance shows that the dominant influence on the predictions of UCS and Es is exerted by the variables of bottom ash dosage and energy absorption capacity. This study reveals that the GEP is a potential tool for establishing the functions and identifying the key variables for predicting the strength and elastic responses of the clay treated with bottom ash. Including a waste material in the proposed formulas can also serve to the environment for the development of recycling and sustainability. © 2014 Elsevier Ltd.

Peak ground acceleration (PGA) has still been considered one of the important factors that plays significant role on the earthquake-induced damage of structures. Thus, prediction of the PGA and selection of appropriate ground motion models often have become a valuable topic for seismic hazard assessments. This paper presents an application in order to predict the PGA by a relatively new prediction tool, genetic expression programming (GEP) and the conventional method of regression, and then aims to select the appropriate ground motion models derived by the GEP and regression methods. The selection was carried out by comparing the prediction performances through a ranking process using a new goodness-of-fit measure, likelihood estimation (LH), recently proposed by Scherbaum et al. (2004, on the use of response spectral reference data for the selection and ranking of ground-motion models for seismic hazard analysis in regions of moderate seismicity: the case of rock motion. Bulletin of the Seismological Society of America 94, 1-22). The Turkish earthquake data properly organized were used for deriving the candidate ground motion models of PGA attenuation equations. The validations of the LH method as well as the GEP and regression models were performed by the key attenuation characteristics, the attenuation equations for Turkey and the case records of Turkish strong ground motion data. The results indicate that majority of the PGA candidate models (GEP and regressions) that are ranked as good qualifications (class A and B) by the LH method generally pass the model validations, but the ones ranked as lower levels (class C) fail. This finding indicates that the LH method can be beneficial for the comparisons of the candidate ground motion models, and the selection of appropriate models for attenuation studies. Even though the GEP-based models that were found to be appropriate by the LH method need some improvements to obtain simple functional forms of PGA predictive relationships, their PGA predictions were reasonably consistent with the model validations. Thus, this study suggests that the GEP approach can be employed for predicting the PGAs in seismic hazard studies at least as a supplement to conventionally derived predictive relationships from the regressions. © 2012 Elsevier B.V.

Cevik A.,University of Gaziantep
Expert Systems with Applications | Year: 2011

This study presents the application of soft computing techniques namely as genetic programming (GP) and stepwise regression (SR), neuro-fuzzy (NF) and neural networks (NN) for modeling of strength enhancement of FRP (fiber-reinforced polymer) confined concrete cylinders. The proposed soft computing models are based on experimental results collected from literature. The accuracy of the proposed soft computing models are quite satisfactory as compared to experimental results. Moreover the results of proposed soft computing formulations are compared with 10 models existing in the literature proposed by various researchers so far and are found to be by far more accurate. © 2010 Elsevier Ltd. All rights reserved.

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