The Impact of Globalization on the Structural Unemployment: An Empirical Reappraisal

Giray Gozgor 한국국제경제학회 2017 International Economic Journal Vol.31 No.4

This paper analyzes the direct effects of various measures of globalization on the structural unemployment in 87 countries for the period from 1991 to 2014. The model specifications are based on the Ricardian Comparative Advantage and the Heckscher–Ohlin models. It is found that one standard deviation increase in the trade openness approximately leads to 0.6 percentage point lower structural unemployment rate. The effects of economic, social, and political aspects of globalization on the structural unemployment are also negative, but they are found as statistically insignificant. The paper also implements various robustness checks and argues potential implications.

Effect of Hemp Fiber Addition on Mechanical Properties of Acrylic Resin: Coupled Experimental and Theoretical Study

Giray Bolayır,Koray Soygun,Melek Kılıç Avşar,Ali Boztuğ,Savaş Kaya,Konstantin P. Katin 한국섬유공학회 2022 Fibers and polymers Vol.23 No.8

We present experimental and theoretical study of the fiber-matrix composites based on polymethyl methacrylate(PMMA) prosthetic material. Hemp fibers of different lengths and concentrations were added to PMMA. In total, ten groupsof composite samples were prepared. Flexural strength test was performed for each sample. We found that the addition ofhemp fibber significantly change the mechanical properties of pristine PMMA. The nature of the interaction between PMMAand hemp fiber were further investigated with scanning electronic microscopy, infrared spectrometry and density functionaltheory. This interaction were described atomistic level in terms of quantum descriptors of reactivity, such as chemicalpotential, electronegativity, chemical hardness and softness, electrophilicity, electrodonating and electroaccepting powers andelectrons transfer. We observed the formations of strong hydrogen bonds between the matrix and fibers, which explain theobserved improvement of mechanical properties.

Dynamic thiol/disulfide homeostasis as a novel indicator of oxidative stress in patients with urolithiasis

Mehmet Giray Sonmez,Betul Kozanhan,Çigdem Damla Deniz,Mehmet Sinan Iyisoy,Muzaffer Tansel Kilinc,Gokhan Ecer,Ahmet Ozturk,Salim Neselioglu,Ozcan Erel 대한비뇨의학회 2019 Investigative and Clinical Urology Vol.60 No.4

Purpose: A dynamic thiol/disulfide balance is pivotal in organizing anti-oxidant defense, detoxification, apoptosis, and enzyme activities, as well as transcription and cellular signal-transfer mechanisms. The connection between urolithiasis and oxidant/antioxidant status, which can be assessed through thiol-disulfide homeostasis (TDH), has not yet been examined. In this study, we evaluated the effects of TDH on the formation, size, and location of stones by examining the associations between TDH parameters and urolithiasis. Materials and Methods: Patients with urolithiasis and healthy controls were recruited. The patients were divided into subgroups in terms of stone size (>15 mm or ≤15 mm) and stone location (nephrolithiasis or ureterolithiasis). TDH parameters were measured using a novel automatic and spectrophotometric method and compared statistically. Results: TDH parameters were different between the urolithiasis and control groups. TDH tended towards the disulfide side in the urolithiasis group. Stone size increased an average 0.14 mm with a 1 µmol/L increase in disulfide level and decreased an average 0.058 mm with a 1 µmol/L increase in native thiol level. Disulfide and native thiol levels were found to be different across patients with stone size >15 mm, ≤15 mm, and controls (p<0.001 and p<0.001, respectively). However, the nephrolithiasis and ureterolithiasis groups were similar in respect of TDH parameters. Conclusions: In this study, it was found that patients with urolithiasis displayed oxidative stress characterized by a TDH tendency towards the disulfide side, and an inadequate antioxidant response identified by a lower level of native thiol as compared with healthy controls.

Mechanical and thermal properties of polyamide versus reinforced PMMA denture base materials

Ali Boztug,Giray Bolayir,Koray Soygun 대한치과보철학회 2013 The Journal of Advanced Prosthodontics Vol.5 No.2

PURPOSE This in vitro study intended to investigate the mechanical and thermal characteristics of Valplast, and of polymethyl methacrylate denture base resin in which different esthetic fibers (E-glass, nylon 6 or nylon 6.6) were added. MATERIALS AND METHODS Five groups were formed: control (PMMA), PMMA-E glass, PMMA-nylon 6, PMMA-nylon 6.6 and Valplast resin. For the transverse strength test the specimens were prepared in accordance with ANSI/ADA specification No.12, and for the impact test ASTM D-256 standard were used. With the intent to evaluate the properties of transverse strength, the three-point bending (n=7) test instrument (Lloyd NK5, Lloyd Instruments Ltd, Fareham Hampshire, UK) was used at 5 mm/min. A Dynatup 9250 HV (Instron, UK) device was employed for the impact strength (n=7). All of the resin samples were tested by using thermo-mechanical analysis (Shimadzu TMA 50, Shimadzu, Japan). The data were analyzed by Kruskal-Wallis and Tukey tests for pairwise comparisons of the groups at the 0.05 level of significance. RESULTS In all mechanical tests, the highest values were observed in Valplast group (transverse strength: 117.22 ± 37.80 MPa, maximum deflection: 27.55 ± 1.48 mm, impact strength: 0.76 ± 0.03 kN). Upon examining the thermo-mechanical analysis data, it was seen that the E value of the control sample was 8.08 MPa, higher than that of the all other samples. CONCLUSION Although Valplast denture material has good mechanical strength, its elastic modulus is not high enough to meet the standard of PMMA materials.

Calculating the collapse margin ratio of RC frames using soft computing models

Ali Sadeghpour,Giray Ozay 국제구조공학회 2022 Structural Engineering and Mechanics, An Int'l Jou Vol.83 No.3

The Collapse Margin Ratio (CMR) is a notable index used for seismic assessment of the structures. As proposed by FEMA P695, a set of analyses including the Nonlinear Static Analysis (NSA), Incremental Dynamic Analysis (IDA), together with Fragility Analysis, which are typically time-taking and computationally unaffordable, need to be conducted, so that the CMR could be obtained. To address this issue and to achieve a quick and efficient method to estimate the CMR, the Artificial Neural Network (ANN), Response Surface Method (RSM), and Adaptive Neuro-Fuzzy Inference System (ANFIS) will be introduced in the current research. Accordingly, using the NSA results, an attempt was made to find a fast and efficient approach to derive the CMR. To this end, 5016 IDA analyses based on FEMA P695 methodology on 114 various Reinforced Concrete (RC) frames with 1 to 12 stories have been carried out. In this respect, five parameters have been used as the independent and desired inputs of the systems. On the other hand, the CMR is regarded as the output of the systems. Accordingly, a double hidden layer neural network with Levenberg-Marquardt training and learning algorithm was taken into account. Moreover, in the RSM approach, the quadratic system incorporating 20 parameters was implemented. Correspondingly, the Analysis of Variance (ANOVA) has been employed to discuss the results taken from the developed model. Additionally, the essential parameters and interactions are extracted, and input parameters are sorted according to their importance. Moreover, the ANFIS using Takagi-Sugeno fuzzy system was employed. Finally, all methods were compared, and the effective parameters and associated relationships were extracted. In contrast to the other approaches, the ANFIS provided the best efficiency and high accuracy with the minimum desired errors. Comparatively, it was obtained that the ANN method is more effective than the RSM and has a higher regression coefficient and lower statistical errors.

Minimization of differential column shortening and sequential analysis of RC 3D-frames using ANN

Njomo, Wilfried W.,Ozay, Giray Techno-Press 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.51 No.6

In the preliminary design stage of an RC 3D-frame, repeated sequential analyses to determine optimal members' sizes and the investigation of the parameters required to minimize the differential column shortening are computational effort consuming, especially when considering various types of loads such as dead load, temperature action, time dependent effects, construction and live loads. Because the desired accuracy at this stage does not justify such luxury, two backpropagation feedforward artificial neural networks have been proposed in order to approximate this information. Instead of using a commercial software package, many references providing advanced principles have been considered to code a program and generate these neural networks. The first one predicts the typical amount of time between two phases, needed to achieve the minimum maximorum differential column shortening. The other network aims to prognosticate sequential analysis results from those of the simultaneous analysis. After the training stages, testing procedures have been carried out in order to ensure the generalization ability of these respective systems. Numerical cases are studied in order to find out how good these ANN match with the sequential finite element analysis. Comparison reveals an acceptable fit, enabling these systems to be safely used in the preliminary design stage.

Minimization of differential column shortening and sequential analysis of RC 3D-frames using ANN

Wilfried W. Njomo,Giray Ozay 국제구조공학회 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.51 No.6

In the preliminary design stage of an RC 3D-frame, repeated sequential analyses to determineoptimal members’ sizes and the investigation of the parameters required to minimize the differential columnshortening are computational effort consuming, especially when considering various types of loads such asdead load, temperature action, time dependent effects, construction and live loads. Because the desiredaccuracy at this stage does not justify such luxury, two backpropagation feedforward artificial neuralnetworks have been proposed in order to approximate this information. Instead of using a commercialsoftware package, many references providing advanced principles have been considered to code a programand generate these neural networks. The first one predicts the typical amount of time between two phases,needed to achieve the minimum maximorum differential column shortening. The other network aims toprognosticate sequential analysis results from those of the simultaneous analysis. After the training stages,testing procedures have been carried out in order to ensure the generalization ability of these respectivesystems. Numerical cases are studied in order to find out how good these ANN match with the sequentialfinite element analysis. Comparison reveals an acceptable fit, enabling these systems to be safely used in thepreliminary design stage.

Factors Affecting Long-Term Care Preferences in Turkey

Ozden Guduk,Hasan Giray Ankara 대한노인병학회 2022 Annals of geriatric medicine and research Vol.26 No.4

Background: This study aimed to identify the long-term care preferences and the factors affecting theses preferences in Turkish society, where long-term care may soon become an important issue. Methods: We applied data from the Family Structure Survey of Turkey conducted in 2016. Using data from 35,475 individuals, we performed descriptive analysis and logistic regressions to determine the preferences and determinants of individuals based on the Andersen Behavior Model. Results: Informal care was the main preference of individuals living in Turkey (37%). Men, individuals living in an extended family, and the young mostly favored informal care, while women, well-educated individuals, and urban individuals preferred institutional or formal care at home. Conclusion: Efforts should be made to raise individuals’ awareness regarding existing long-term care services. These services should be strengthened in line with society's preferences, considering regional differences.

Magnesite tailing as low-cost adsorbent for the removal of copper (II) ions from aqueous solution

İlker Kıpçak,Turgut Giray Isıyel 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.8

The removal of Cu(II) ions from aqueous solution using magnesite tailing was investigated. Batch kinetic and equilibrium experiments were conducted to study the effects of initial pH, adsorbent dosage, contact time, initial concentration and temperature. The pseudo-first-order, pseudo-second-order and intraparticle diffusion models were used to study the kinetic data. The experimental data were best fitted by the pseudo-second-order kinetic model. The linear Langmuir and Freundlich adsorption equations were applied to describe the equilibrium isotherms. The equilibrium data fit very well the Langmuir model, and the maximum adsorption capacity was estimated as 12.18mg/g at 45 oC. Thermodynamic parameters such as enthalpy change (ΔHo), free energy change (ΔGo) and entropy change (ΔSo) were calculated, and it was found that the adsorption process was spontaneous and endothermic. The results showed that magnesite tailing is a suitable adsorbent for the removal of Cu(II) ions from aqueous solutions.

Testicular Adrenal Rest Tumor in 11-Beta-Hydroxylase Deficiency Driven Congenital Adrenal Hyperplasia

Mehmet Kaynar,Mehmet Giray Sönmez,Yaşar Ünlü,Tuna Karatağ,Erdem Tekinarslan,Alpay Sümer 대한비뇨의학회 2014 Investigative and Clinical Urology Vol.55 No.4

Testicular adrenal rest tumors (TART) occur often as asymptomatic nodules in corticotropin-dependent lesions aberrant adrenal tissue in congenital adrenal hyperplasia(CAH) patients. The present manuscript is about an unusual case of a 16-year-old CAHpatient due to 11β-hydroxylase deficiency. He underwent testicle biopsy because of testicletumor suspicion and diagnosed with TART.