Sahinbey, Turkey

Hasan Kalyoncu University
Sahinbey, Turkey
Time filter
Source Type

Batmaz S.,Mersin State Hospital | Kaymak S.U.,Ankara Ataturk Training and Research Hospital | Ozalp E.,Ankara Oncology Training and Research Hospital | Turkcapar M.H.,Hasan Kalyoncu University
Comprehensive Psychiatry | Year: 2013

Background There is very limited data about the cognitive structure of bipolar depression when compared to unipolar depression. The aim of the study was to look into the differences between unipolar and bipolar depressed patients regarding their cognitive structure in view of Beck's cognitive theory. Methods In this study, 70 bipolar patients during a depressive episode, 189 unipolar depressed patients and 120 healthy subjects were recruited. The participants were interviewed by using a structured clinical diagnostic scale. To evaluate the cognitive structure differences, the Automatic Thoughts Questionnaire (ATQ) and the Dysfunctional Attitude Scale (DAS) were used. Results We found that on the mean ATQ total score, the unipolar depressed patients scored significantly higher (92.9 ± 22.7) than both the bipolar depressed patients (73.2 ± 24.7) and the healthy subjects (47.1 ± 19.6), even after controlling for all confounding factors, e.g. gender, marital status, depressive symptom severity (F = 157.872, p < 0.001). The bipolar depressed patients also scored significantly higher on the mean ATQ total score than the healthy controls. On the mean DAS total score, and on the mean score of its subscale of need for approval, the bipolar depressed patients scored (152.8 ± 21.2 and 48.2 ± 7.4, respectively) significantly higher than both the unipolar depressed patients (160.9 ± 29.0 and 51.9 ± 9.7, respectively) and the healthy subjects (127.9 ± 32.8 and 40.2 ± 12.2, respectively), even after controlling for any confounding factor (F = 45.803 [p < 0.001] and F = 43.206 [p < 0.001], respectively). On the mean score of the perfectionistic attitude subscale of the DAS, the depressed groups scored significantly higher than the healthy subjects, but they did not seem to separate from each other (F = 41.599, p < 0.001). Conclusions These results may help enhance the understanding of the potentially unique psychotherapeutic targets and the underlying cognitive theory of bipolar depression. © 2013 Elsevier Inc. All rights reserved.

Gorczyca T.W.,Western Michigan University | Hasoglu M.F.,Hasan Kalyoncu University | Manson S.T.,Georgia State University
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2012

It is demonstrated that the effect of a static cage potential on the photoionization of endohedrally enclosed atoms can be incorporated into standard R-matrix calculations using one of two independent methods. For photoionization processes occurring entirely within the fullerene, the outer-region solutions can be modified by the additional cage potential to yield phase-shifted Coulomb functions that are matched to the inner-region R matrix. Alternatively, if the cage potential is contained within the R-matrix "box," it can be directly incorporated into the formalism via simple one-electron integral contributions to the Hamiltonian, yielding a modified R matrix. Both methods are applied to the photoionization of Xe@C 60 in the vicinity of the giant 4d→εf shape resonance and are found to be in excellent agreement with each other. © 2012 American Physical Society.

Guneyisi E.M.,University of Gaziantep | D'Aniello M.,University of Naples Federico II | Landolfo R.,University of Naples Federico II | Mermerdas K.,Hasan Kalyoncu University
Journal of Constructional Steel Research | Year: 2013

The ductile design of steel structures is directly influenced by the flexural behaviour of steel beams, which should be sufficient to allow plastic hinges to rotate until the collapse mechanism is completely developed. To guarantee the achievement of such a performance, the beam flexural overstrength must be quantified to appropriately apply capacity design principles. To this aim, analytical formulations to predict the flexural overstrength factor (s) of steel beams with a wide range of cross-section typologies (I and H sections, square and rectangular hollow sections) were developed based on gene expression programming (GEP). An experimental database was gathered from the available literature and processed to obtain the training and testing databases for the derivation of the closed-form solution through GEP. The independent variables used for the development of the prediction models were the geometric properties of the sections, the mechanical properties of the material, and the shear length of the steel beams. The predictions of the proposed GEP-based models were compared with the results obtained using the existing analytical equations proposed in the current literature. Comparative analysis revealed that the proposed formulation provides a more accurate prediction of beam overstrength. © 2013 Elsevier Ltd.

D'Aniello M.,University of Naples Federico II | Guneyisi E.M.,University of Gaziantep | Landolfo R.,University of Naples Federico II | Mermerdas K.,Hasan Kalyoncu University
Thin-Walled Structures | Year: 2014

In this paper, a soft-computing based study aimed to estimate the available rotation capacity of cold-formed rectangular and square hollow section (RHS-SHS) steel beams is described and novel mathematical models based on neural network (NN) and genetic expression programming (GEP) are proposed. In order to develop the proposed formulations, a wide experimental database obtained from available studies in the literature has been considered. The data used in the NN and GEP models are arranged in a format of eight input parameters covering both geometrical and mechanical properties such as width, depth and wall thickness of cross section, inside corner radius, yield stress, ratio of modulus of elasticity to hardening modulus, ratio of the strain under initial hardening to yield strain and shear length. The accuracy of the proposed formulations is verified against the experimental data and the rates of efficiency and performance are compared with those provided by analytical semi-empirical formulation developed by some of the Authors in a previous study. The proposed prediction models proved that the NN and GEP methods have strong potential for predicting available rotation capacity of cold-formed RHS-SHS steel beams. © 2013 Elsevier Ltd.

Gesoglu M.,University of Gaziantep | Guneyisi E.,University of Gaziantep | Ali B.,University of Gaziantep | Mermerdas K.,Hasan Kalyoncu University
Construction and Building Materials | Year: 2013

In this paper, effect of steam and water curing on the compressive strength development and transport properties such as water sorptivity, rapid chloride ion permeability, and gas permeability of concretes containing various volumes of lightweight fly ash aggregate (LWA) were investigated. In production of concrete, a fixed amount of lightweight coarse (LWCA) aggregate plus varying amounts of lightweight fine aggregate (LWFA) were used. Utilization of LWFA was achieved by volumetric substitution of fine aggregate with five different replacement levels namely, 0%, 25%, 50%, 75%, and 100%. Therefore, five different concrete mixtures were produced for this experimental study. The produced concretes were divided into two parts one of which was initially steam cured while the other was directly exposed to water curing. After initial steam curing regime, the steam cured (SC) concretes were also transferred to water until testing Mechanical properties of concretes were monitored through compressive strength development over 56 days, while transport properties were measured by means of water sorptivity, gas permeability and rapid chloride permeability tests conducted at 28 and 56 days. © 2013 Published by Elsevier Ltd. All rights reserved.

Cabalar A.F.,University of Gaziantep | Mustafa W.S.,Hasan Kalyoncu University
Engineering Geology | Year: 2015

Fall cone tests were performed on clay-sand mixtures to investigate the variation of liquid limit with sand content and the link between undrained shear strength and water content for various sand contents in the mixtures. Five different particle gradations (4.75-0.075. mm, 4.75-2.0. mm, 1.18-0.6. mm, 0.6-0.075. mm, and 0.425-0.3. mm) of sands having distinct shapes (rounded and angular) were added to a low plasticity clay with mixture ratios of 0%, 10%, 20%, 30%, 40%, and 50%. Data of the clay-sand mixtures showed that the depth of cone penetration against water content relationship is about linear. The liquid limit estimates of the mixtures were measured to be slightly affected by the gradation and shape of the grains in the range of sand contents employed. The obtained results indicated a decrease of undrained shear strength with an increase in the amount of sand. The use of rounded sands in a clay matrix leads to the development of higher undrained shear strength values, on which gradation of the sands has no effect. © 2015 Published by Elsevier B.V.

Guneyisi E.,University of Gaziantep | Gesolu M.,University of Gaziantep | Booya E.,Salahaddin University Erbil | Mermerdas K.,Hasan Kalyoncu University
Construction and Building Materials | Year: 2015

This paper presents the results of an experimental study on the hardened characteristics of the self-compacting concretes made with cold bond fly ash lightweight aggregates. Binary and ternary use of fly ash (FA) and silica fume (SF) blends have been considered in the production of self-compacting cold bonded fly ash lightweight aggregate concretes (SCLWCs). For this, a total of 9 SCLWC mixtures were proportioned having constant water-binder ratio of 0.35 and the total binder content of 550 kg/m3. The control mixture contained only Portland cement (PC) as the binder while the remaining mixtures having binary and ternary blends of PC, FA, and SF. Properties that include compressive strength and ultrasonic pulse velocity, chloride ion penetration, gas permeability, water absorption by total immersion and by capillary absorption were investigated at two curing ages of 28 and 56 days. Test results have showed that incorporating the mineral admixtures enhanced significantly the permeability characteristics. Moreover, it was observed that the compressive strength of the SCLWCs with SF was much higher than those of the control concrete. © 2014 Elsevier Ltd. All rights reserved.

Nassani D.E.,Hasan Kalyoncu University
International Journal of Steel Structures | Year: 2014

This paper reports the results of a study conducted to investigate the behaviour of steel cap plate connections. In the analysis and design, connections are characterized as either rigid or pinned and between these two extremities lies the actual behaviour of steel frame connections, which is semi-rigid. This classification is characterized by the nonlinear moment-rotation relationship which must be incorporated in the analysis. A cap plate connection is widely used in industrial steel frames for its advantages over other types of building connections, but the response of such a connection has not sufficiently been experimentally determined. In this research, the behaviour of cap plate connections was studied by testing four full-scale connections. Experimental results obtained would add valuable information to the available test data concerning steel connections since sparse data is available in the literature for this type of connection. Mathematical and numerical models were used to analyze the cap plate connection and close correlations were found between these models and the experimental results. © 2014, Korean Society of Steel Construction and Springer-Verlag Berlin Heidelberg.

Abdul Hafez A.H.,Hasan Kalyoncu University
Control Engineering and Applied Informatics | Year: 2014

This paper presents a new stable hybrid visual servo controller to complete the task of robot arm positioning. Our method is generic hybrid method and superior to the state of the art. The objective function is designed to include the full but weighted 2D and 3D available information. The positioning task has been formulated as a minimization problem. Here, each of the 2D and 3D error functions is used to control the six degrees of freedom. The importance weights are computed to satisfy a set of constraints defined by the visual servoing process. Stability analysis is also presented for the proposed control law. The experimental evaluation is done in order to show the enhanced performance of the visual servoing process. Simulation results show that this method provides an efficient solution to the camera retreat and features visibility problems. Performance of the visual servoing system is evaluated by its ability to keep features visible in the image and the Cartesian trajectory within the robot workspace during the process.

Eskandari M.,Hasan Kalyoncu University | Toygar O.,Eastern Mediterranean University
Computer Vision and Image Understanding | Year: 2015

Abstract The focus of this paper is on proposing new schemes based on score level and feature level fusion to fuse face and iris modalities by employing several global and local feature extraction methods in order to effectively code face and iris modalities. The proposed schemes are examined using different techniques at matching score level and feature level fusion on CASIA Iris Distance database, Print Attack face database, Replay Attack face database and IIIT-Delhi Contact Lens iris database. The proposed schemes involve the consideration of Particle Swarm Optimization (PSO) and Backtracking Search Algorithm (BSA) in order to select optimized features and weights to achieve robust recognition system by reducing the number of features in feature level fusion of the multimodal biometric system and optimizing the weights assigned to the face-iris multimodal biometric system scores in score level fusion step. Additionally, in order to improve face and iris recognition systems and subsequently the recognition of multimodal face-iris biometric system, the proposed methods attempt to correct and align the location of both eyes by measuring the iris rotation angle. Demonstration of the results based on both identification and verification rates clarifies that the proposed fusion schemes obtain a significant improvement over unimodal and other multimodal methods implemented in this study. Furthermore, the robustness of the proposed multimodal schemes is demonstrated against spoof attacks on several face and iris spoofing datasets. © 2015 Elsevier Inc.

Loading Hasan Kalyoncu University collaborators
Loading Hasan Kalyoncu University collaborators