Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Dertli, Enes(116)
- Şahin, Engin(48)
- Kaya, Yunus(46)
- Özen, Soner(46)
- İspirli, Hümeyra(45)
- Pat, Suat(44)
- Şenay, Volkan(42)
- Korkmaz, Şadan(36)
- Yilmaz, Mustafa Tahsin(33)
- Kutlu, Naciye(32)
- Cuce, Erdem(31)
- Öner, Erdal(31)
- Artar, Musa(30)
- Ertugrul, Mehmet(29)
- Hasar, Ugur Cem(29)
- Mercan, Emin(28)
- Bayraktar, Bülent(27)
- Bayram, Sinan(27)
- Can, Zehra(25)
- Ecem Bayram, Nesrin(25)
- Çolak, Murat(23)
- Özdemir, Akın(23)
- Cuce, Pinar Mert(22)
- Sert, Durmuş(22)
- Ayata, Ümit(21)
- Bayram, Ozkan(21)
- Dirican, Ebubekir(20)
- Abdioglu, Murat(19)
- Ayazoglu, Rabil(19)
- Birinci, Ahmet(19)
- Kamiloğlu, Aybike(19)
- Gerçek, Yusuf Can(18)
- Taylan, Osman(18)
- Tozlu, Alperen(18)
- Gul, Volkan(15)
- Hasar, Ugur C.(15)
- Kadakal, Mahir(15)
- Sagdic, Osman(15)
- Ergün, Mustafa(14)
- Kadakal, Huriye(14)
Yayınlar
- MakaleAçık Erişim2014Scopus SJRQ3Antioxidant enzyme inhibitor role of phosphine metal complexes in lung and leukemia cell lines
Saygideʇer Demir, Burcu; Keleş, Tuʇba; Serindaʇ, Osman
Phosphine metal complexes have been recently evaluated in the field of cancer therapy. In this research, the cytotoxic effects of some metal phosphines { [PdCl2((CH2OH)CH2)CH3] (C1), [RuCl2(((CH2OH)CH2)CH3) (C2), [PtCl2((Ph2PCH2)CH3)(timin) (C3) } on K562 (human myelogenous leukemia cell line) and A549 (adenocarcinomic human alveolar basal epithelial cells) cells were investigated using the MTT test. C1 and C2 are water-soluble metal complexes, which may have some advantages in in vitro and in vivo studies. The effects of the above-mentioned metal complexes on thioredoxin reductase (TrxR) (EC: 1.8.1.9), glutathione peroxidase (GPx) (EC: 1.11.1.9), and catalase (Cat) (EC: 1.11.1.6) enzymes were also tested. The results of this research showed that all three metal complexes indicated dose-dependent cytotoxicity on A549 and K562 cell lines and that the complexes inhibited different percentages of the TrxR, GPx, and Cat enzymes of these tumor cells.
AtıfScopus7WoS6OpenAlex9
İncele - MakaleYalnız künye2014Scopus SJRQ2Effects of initial cooling conditions and measurement heights on the levitation performance of bulk MgB2 superconductor at different measurement temperatures
Erdem, O.; Ozturk, K.; Guner, S.B.; Celik, S.; Yanmaz, E.
The levitation properties of MgB2 prepared by hot press at 200 ° C and then pellet/closed tube method has been investigated. The vertical and lateral levitation forces (Fz and Fx) on a cylindrical NdFeB permanent magnet (PM) below a disk-shaped bulk MgB2 were measured during the vertical and lateral traverses of the PM in different cooling heights (CHs) and measurement heights (MHs) at temperatures of 20, 25 and 30 K to investigate the effect of the initial CH and MH on the levitation performance of MgB2. For temperatures below 30 K, it was observed that Fz increases with increasing CH. However, a minute variation in Fz and a big hysteresis loop are observed at 30 K. From the lateral traverses, it was obtained that the Fz with attractive character increases with decreasing MH and the hysteresis effect increases for small MHs due to the increment of the magnetic field intensity which the sample feels with decreasing MH. In addition, it was seen that the character of Fx varies depending on both MH and measurement temperature. The higher hysteresis obtained in Fx than in Fz during lateral traverses implies that the motion of the flux lines in MgB2 is especially in lateral rather than vertical direction. Finally in this study, it was shown that the levitation performance of MgB2 depends not only on the measurement temperature but also on the CH and MH conditions. These results can be useful for optimizing the levitation performance of MgB2 superconductors for potential applications.
AtıfScopus20WoS21OpenAlex21İncele - MakaleAçık Erişim2014Scopus SJRQ2FT-IR, FT-Raman, NMR, UV and quantum chemical studies on monomeric and dimeric conformations of 3,5-dimethyl-4-methoxybenzoic acid
Karabacak, Mehmet; Sinha, Leena; Prasad, Onkar; Asiri, Abdullah M.; Cinar, Mehmet; Shukla, Vikas K.
Extensive spectroscopic investigations along with theoretical quantum chemical studies on 3,5-dimethyl-4-methoxybenzoic acid (DMMBA) have been consummated. The fundamental vibrational transitions were addressed by experimental FT-IR (4000-400 cm-1) and FT-Raman (4000-10 cm -1) techniques and density functional calculations at B3LYP/6-311++G(d,p) and B3LYP/6-311++G(df,pd) levels of theory. The 1H, 13C and DEPT 135 NMR spectra of studied compound were recorded in deuterated dimethylsulfoxide (DMSO-d6), and compared with computed data obtained by using gauge including atomic orbital (GIAO) method. The electronic absorption spectra in methanol and ethanol solution were evaluated in the range of 200-400 nm, and TD-DFT method was chosen for computational study. The spectroscopic and theoretical results were compared to the corresponding properties for monomer and dimer structures for the most stable conformer. Stability of the molecule arising from hyperconjugative interactions and charge delocalization has been analyzed using natural bond orbital (NBO) analysis. Moreover, the thermodynamic and nonlinear optical (NLO) properties were evaluated.
AtıfScopus34WoS34
İncele - MakaleYalnız künye2014Scopus SJRQ1Power analysis of multilayer structures composed of conventional materials and bi-anisotropic metamaterial slabs
Hasar, Ugur Cem; Bute, Musa; Barroso, Joaquim J.; Sabah, Cumali; Kaya, Yunus; Ertugrul, Mehmet
In this paper, we analyze wave propagation properties (transmitted, reflected, and absorbed powers) of composite multilayer structures consisting of bi-anisotropic metamaterial (MM) slabs and conventional isotropic materials. We also separately investigate the propagation properties of bi-anisotropicMMslabs and conventional materials to better interpret the results. We consider two different bi-anisotropic MM slab structures composed of only splitring- resonators (SRRs) and composing SRRs and a rod. In the analysis, we apply the well-known transfer matrix method to obtain transmitted, reflected, and absorbed powers of the composite structures. From the analysis, we note the following three important results. First, while the transmitted powers from forward and backward directions of the multilayer structure are identical (reciprocal feature), reflected (and absorbed) powers from forward and backward directions of the multilayer structure are different. This difference arises from reflection asymmetric nature of the bi-anisotropic MM slabs. Second, whereas the conventional material loss influences propagation characteristics aside resonance frequencies of bi-anisotropic MM slabs, bi-anisotropic MM loss worsens propagation properties of the multilayer structure at resonance frequencies of these slabs. Third, variations in (or determination of) electromagnetic properties of low-loss thin conventional materials in between two bi-anisotropic MM slabs can be realized at frequencies in which conventional materials demonstrate thickness-resonance effect.
AtıfScopus11WoS11OpenAlex13İncele - MakaleYayıncıda açık erişim2014Scopus SJRQ2Continuous contact problem for two elastic layers resting on an elastic half-infinite plane
Öner, Erdal; Birinci, Ahmet
The continuous contact problem for two elastic layers resting on an elastic half-infinite plane and loaded by means of a rigid stamp is presented. The elastic layers have different heights and elastic constants. An external load is applied to the upper elastic layer by means of a rigid stamp. The problem is solved under the assumptions that all surfaces are frictionless, body forces of elastic layers are taken into account, and only compressive normal tractions can be transmitted through the interfaces. General expressions of stresses and displacements are obtained by using the fundamental equations of the theory of elasticity and the integral transform technique. Substituting the stress and the displacement expressions into the boundary conditions, the problem is reduced to a singular integral equation, in which the function of contact stresses under the rigid stamp is unknown. The integral equation is solved numerically by making use of the appropriate Gauss-Chebyshev integration formula for circular and rectangular stamp profiles. The contact stresses under the rigid stamp, contact areas, initial separation loads, and initial separation distances between the two elastic layers and the lower-layer elastic half-infinite plane are obtained numerically for various dimensionless quantities and shown in graphics and tables.
AtıfScopus24WoS25OpenAlex26İncele - MakaleAçık Erişim2014Scopus SJRQ2The spectroscopic (FT-IR, FT-Raman, UV and NMR) first order hyperpolarizability and HOMO-LUMO analysis of dansyl chloride
Karabacak, M.; Cinar, M.; Kurt, M.; Poiyamozhi, A.; Sundaraganesan, N.
The solid phase FT-IR and FT-Raman spectra of dansyl chloride (DC) have been recorded in the regions 400-4000 and 50-4000 cm-1, respectively. The spectra have been interpreted in terms of fundamentals modes, combination and overtone bands. The structure of the molecule has been optimized and the structural characteristics have been determined by density functional theory (B3LYP) method with 6-311++G(d,p) as basis set. The vibrational frequencies were calculated for most stable conformer and were compared with the experimental frequencies, which yield good agreement between observed and calculated frequencies. The infrared and Raman spectra have also been predicted from the calculated intensities. 1H and 13C NMR spectra were recorded and 1H and 13C nuclear magnetic resonance chemical shifts of the molecule were calculated using the gauge independent atomic orbital (GIAO) method. UV-Visible spectrum of the compound was recorded in the region 200-600 nm and the electronic properties HOMO and LUMO energies were measured by time-dependent TD-DFT approach. Nonlinear optical and thermodynamic properties were interpreted. All the calculated results were compared with the available experimental data of the title molecule.
AtıfScopus23WoS22OpenAlex29İncele - MakaleAçık Erişim2014Scopus SJRQ1Simultaneous separation and preconcentration of Ni(II) and Cu(II) ions by coprecipitation without any carrier element in some food and water samples
Duran, Celal; Tumay, Sureyya O.; Ozdes, Duygu; Serencam, Huseyin; Bektas, Hakan
A simple and highly sensitive separation and preconcentration procedure, which has minimal impact on the environment, has been developed. The procedure is based on the carrier element-free coprecipitation of Ni(II) and Cu(II) ions by using 2-{4-[2-(1H-Indol-3-yl)ethyl]-3-(4-chlorobenzyl)-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl}-N′-(pyrrol-2-ylmethyliden)acetohydrazide (ICOTPA), as an organic coprecipitant. The levels of analyte ions were determined by flame atomic absorption spectrometry. The detection limits for Ni(II) and Cu(II) ions were found to be 0.27 and 0.58 μg L-1, respectively, and the relative standard deviations for the analyte ions were lower than 4.0%. Spike tests and certified reference material analyses were performed to validate the method. The method was successfully applied for the determination of Ni(II) and Cu(II) ions levels in sea and stream water as liquid samples and red lentil and rice as solid samples.
AtıfScopus26WoS23OpenAlex26İncele - MakaleYalnız künye2014Scopus SJRQ4Fatty acid profile and quality specifications of chocolate spreads
Kara, Hasan Hüseyin; Çaǧlar, Abdullah; Mercan, Emin; Gök, Gökçen; Taşbaş, Sultan; Arslan, Merve
This study examined the characteristics of 13 samples from 10 different brands of chocolate spread that are sold in markets in Turkey. Humidity level, oil content, pH value, color values (L*, a*, b*), were determined, chocolate fat samples were tested for free fat acidity rate, peroxide value, iodine value and fat acids composition. The samples composed of 14 different fatty acids. Dominant fatty acids were palmitic acid (9.82-27.19 %), oleic acid (26.27-56.05 %) and linoleic acid (10.87-52.40 %). It was observed that saturated fatty acids (SFA) of the samples ranged between 17.01 and 32.03 %, monounsaturated fatty acids (MUFA) ranged between 19.74 and 57.00 % and polyunsaturated fatty acids (PUFA) ranged between 11.01 and 52.51 %. The analyses showed that contents of the samples complied with legal limits. The types of fatty acids used were determined to be remarkable due to their fatty acids composition.
AtıfScopus5WoS6İncele - MakaleAçık Erişim2014Scopus SJRQ2Identification of structural and spectral features of synthesized cyano-stilbene dye derivatives: A comparative experimental and DFT study
Karabacak, M.; Asiri, A.M.; Al-Youbi, A.O.; Qusti, A.H.; Cinar, M.
The synthesized three dye derivatives of cyano-stilbene monomer were identified by experimental spectroscopic techniques and density functional approach. The optimized geometrical structure, vibrational and electronic transitions along with the nonlinear optical (NLO) properties of those compounds were presented in this study. The vibrational spectra of investigated compounds were recorded in solid state with FT-IR and FT-Raman spectrometry in the range of 4000-400 cm-1 and 3600-50 cm-1, respectively. The theoretical ground state equilibrium conformations and vibrational wavenumbers were carried out by using density functional method with 6-311G(d,p) basis set. Assignments of the fundamental vibrational modes were examined on the basis of the measured data and total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. The UV absorption spectra of monomers were observed in the range of 200-600 nm in chloroform, acetonitrile and toluene, and time dependent DFT method was used to obtain the electronic properties. The linear polarizability and first hyperpolarizability of the studied molecules indicates that the title compounds can be used as a good nonlinear optical material. A detailed description of spectroscopic behaviors of compounds was given based on the comparison of experimental measurements and theoretical computations.
AtıfScopus22WoS21OpenAlex22İncele - MakaleYalnız künye2014Scopus SJRQ4Antagonistic effects of Satureja hortensis essential oil against AFB, on human lymphocytes in vitro
Ceker, S.; Agar, G.; Alpsoy, L.; Nardemir, G.; Kizil, H.E.
Satureja hortensis L. (Lamiaceae) has been used as a folk remedy to treat various such as cramps, muscle pains, nausea, indigestion, diarrhea, and infectious diseases. In this study, the antagonistic effects of essential oil of S. hortensis (SHE) were studied against aflatoxin B1 (AFB1) in human lymphocytes in vitro. The analysis of the essential oil was performed by using Gas chromatography-mass spectrometry (GC-MS). Anti-genotoxic effects of the SHEs was evaluated using sister chromatid exchange (SCE), micronuclei (MN) tests against AFB1. Also level of malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities used to determine the anti-oxidative effects of the SHEs. This result showed AFB1 (5 μM) increased the frequencies of SCE, MN and the level of MDA. AFB1 at the same concentration decreased the activities of SOD and GPx. However, different concentrations of SHE with AFB1 decreased the frequency of SCE and MN and level of MDA and also increased the activities of SOD and GPx significantly. Especially, the 1.0, 1.5, 2.0 μL dose of SHE are more effective than other doses. The results of this experiment have clearly shown that SHE has strong antioxidative and antigenotoxic effects, these biological activities of SHEs can be due to its component.
AtıfScopus6WoS6OpenAlex10İncele - MakaleYalnız künye2014Scopus SJRQ4Some Physicochemical Characteristics, Bioactive Content and Antioxidant Characteristics of Non-Sprayed Barberry (Berberis vulgaris L.) Fruits from Turkey; [Physikalisch-chemische Eigenschaften, bioaktive Inhaltsstoffe und antioxidative Eigenschaften von nicht mit Pflanzenschutzmitteln behandelten Früchten der Berberitze (Berberis vulgaris L.) aus der Türkei]
Yildiz, Hilal; Ercisli, Sezai; Sengul, Memnune; Topdas, Elif Feyza; Beyhan, Omer; Cakir, Ozlem; Narmanlioglu, Haluk Kemal; Orhan, Emine
Increasing consumer demands for indigenous, non-sprayed with pesticides and less-known or “forgotten” fruits necessitate knowledge on their breeding, cultivation, biochemical content, harvesting and marketing. Anatolia is rich for wild edible fruit species and barberry is abundant throughout Anatolia. The aim of this study was to determine some important physicochemical characteristics, bioactive content and antioxidant capacity of fruits from nineteen promising barberry (Berberis vulgaris L.) genotypes grown in the Coruh valley, Northeastern Anatolia. The results indicated genotype-specific differences for most of the physicochemical characteristics, antioxidant capacity and the content of some bioactive compounds. Fruit mass ranged from 0.073 (‘Coruh-7’) to 0.267 g (‘Coruh-11’). Total phenolic content ranged from 2532 (‘Coruh-’) to 3719 mg GAE per liter fruit juice (‘Coruh-11’). The genotype ‘Coruh-12’ had the highest total monomeric anthocyanin content (1004 mg per liter fruit juice) as cyanidin-3-glucoside. The highest total antioxidant capacity was observed in fruits of ‘Coruh-8’ and ‘Coruh-9’ genotypes with all three antioxidant-determining methods. We conclude that the barberry fruits represent a good source of bioactive phytochemicals because of their high phenolic and anthocyanin contents.
AtıfScopus34WoS26OpenAlex36İncele - MakaleAçık Erişim2014Scopus SJRQ1Steady, dynamic and creep rheological analysis as a novel approach to detect honey adulteration by fructose and saccharose syrups: Correlations with HPLC-RID results
Yilmaz, Mustafa Tahsin; Tatlisu, Nevruz Berna; Toker, Omer Said; Karaman, Safa; Dertli, Enes; Sagdic, Osman; Arici, Muhammet
In this study, natural honey was adulterated with the addition of adulterants, namely saccharose and fructose syrups at a ratio of 0%, 10%, 20%, 30%, 40% and 50% by weight. Steady, dynamic and creep tests were conducted, revealing that the changes in the flow, viscoelastic and creep behavior of natural honey were clear and remarkable. Syrup addition decreased viscosity (η), storage (G') and loss modulus (G″) values of the control honey samples. Deformation represented by the compliance (J(t)) values was more prominent in the adulterated honey samples. In addition, HPLC-RID analysis was conducted to determine major sugar composition of the adulterated samples. Pearson's correlation test indicated that there were significant (P<0.05; 0.01) correlations between sugar composition and rheology parameters, η (viscosity), K″, K* (intercepts for G″ and complex modulus (G*), respectively) and η0 (viscosity of Maxwell dashpot), suggesting that K', K″, K* and η0 could be prominent indicators for presence of saccharose or fructose syrups added in natural honey within the studied concentration levels. These results suggested that use of steady, dynamic and creep analysis would be a novel and potential approach to detect honey adulteration by fructose and saccharose syrups.
AtıfScopus81WoS72OpenAlex80İncele - MakaleAçık Erişim2014Scopus SJRQ3Free vibration analysis of a laminated composite beam with various boundary conditions
Balci, Murat; Nalbant, Mustafa Oǧuz; Kara, Ercan; Gündoǧdu, Ömer
This study presents a free vibration analysis of a laminated composite beam, based on the Euler-Bernoulli beam theory. A numerical model of the laminated composite beam was obtained for various boundary conditions based on different length-to-thickness ratios for a number of layers, using the finite element method. A planar beam bending element with two nodes, each having two degrees of freedom, was chosen according to Euler-Bernoulli beam theory. The natural frequencies of the laminated composite beam were obtained for each case, and presented in such a way as to display the effect of these changes on the natural frequencies. Eight natural frequencies of clamped-free, clamped-clamped (CC) and simple-simple (SS) composite beams were first obtained for different length-to-thickness ratios (Lx /h), numbers of layers, layer angles and for their different positions. It can be seen that natural frequencies decrease for all modes with increasing length-to-thickness ratio in all cases.
AtıfScopus19WoS11OpenAlex15İncele - MakaleAçık Erişim2014Scopus SJRQ1Microwave method for reference-plane-invariant and thickness-independent permittivity determination of liquid materials
Hasar, U.C.; Kaya, Y.; Bute, M.; Barroso, J.J.; Ertugrul, M.
An attractive transmission-reflection method based on reference-plane invariant and thickness-independent expressions has been proposed for accurate and unique retrieval of complex permittivity of dielectric liquid samples. The method uses both branch-index-independent expressions and a restricted solution set for determining unique and fast complex permittivities. A 2D graphical method has been applied to demonstrate the operation and validation of the proposed method. A uncertainty analysis has been performed to monitor how the accuracy of the proposed method can be improved by a correct selection of sample holder properties. Scattering parameter measurements of two tested reference liquids (distilled water and methanol) have been carried out for comparison of various techniques with the proposed one when the reference-planes and sample thickness are not precisely known. We note from the comparison that whereas other techniques are seriously affected by imprecise knowledge of both reference-planes and sample thickness, the proposed method removes this restriction.
AtıfScopus20WoS20OpenAlex21İncele - MakaleYalnız künye2014Scopus SJRQ1Purification and characterization of an alkaline pectin lyase produced by a newly isolated brevibacillus borstelensis (p35) and its applications in fruit juice and oil extraction
Demir, Nazan; Nadaroglu, Hayrunnisa; Demir, Yasar; Isik, Ceyhun; Taskin, Esen; Adiguzel, Ahmet; Gulluce, Medine
An alkaline pectin lyase (Pnl) (EC 4.2.2.10) secreted by Brevibacillus borstelensis P35 (genBank number: FJ417406) was purifed using ammonium sulfate fractionation, anion exchange chromatography on DEaE-cellulose and gel fltration chromatography on Sephadex g-150. The pH and temperature optima of the enzyme were found to be 8.0 and 60 °C. The enzyme does not loose activity up to 60 °C if exposed for 1 h. The values of Kmand Vmax of the enzyme were 0.625 mg/ml and 126.32 s-1, respectively. The molecular weight was found to be 36 ± 01 kDa. The presence of 10 mM concentration of Ca2+, Cu2+, Mn2+, Mg2+, Zn2+, Hg2+, Fe2+ and EDTa, L-cystein, ascorbic acid signifcantly enhanced the Pnl of the purifed enzyme. In the course of the laboratory trials, it was demonstrated that Pnl from B. borstelensis (P35) could be successfully applied to the production and clarif-cation of fruit juice and oil extraction.
AtıfScopus36WoS31OpenAlex35İncele - MakaleAçık Erişim2014Scopus SJRQ2Solution of a receding contact problem using an analytical method and a finite element method
Öner, Erdal; Yaylaci, Murat; Birinci, Ahmet
In this study, a receding contact problem for two elastic layers supported by a Winkler foundation is handled using two different methods such as an analytical method and a finite element method. Firstly, the problem is solved analytically using linear elasticity theory. Then, in order to solve the same problem in a different way, a finite element model of the problem is created by ANSYS software, and finite element analysis of the problem is performed. The contact stresses and the contact areas at the interfaces between punch-Layer 2 and Layer 1-Layer 2 are obtained for both solutions, and it is shown that the finite element method indicates a good agreement with the analytical method.
AtıfScopus36WoS37OpenAlex25İncele - MakaleYalnız künye2014Scopus SJRQ2Comparison of the dynamic responses of gülburnu highway bridge using single and triple concave friction pendulums
Yurdakul, Muhammet; Ates, Sevket; Altunisik, Ahmet Can
The main object of this study is to determine and compare the structural behavior of base isolated long span highway bridge, Gülburnu Highway Bridge, using single concave friction pendulum (SCFP) and triple concave friction pendulum (TCFP). The bridge is seismically isolated in the design phase to increase the main period and reduce the horizontal forces with moments using SCFP bearings. In the content of the paper, firstly three dimensional finite element model (FEM) of the bridge is constituted using project drawings by SAP2000 software. The dynamic characteristics such as natural frequencies and periods, and the structural response such as displacements, axial forces, shear forces and torsional moments are attained from the modal and dynamic analyses. After, FEM of the bridge is updated using TCFP and the analyses are performed. At the end of the study, the dynamic characteristics and internal forces are compared with each other to extract the TCFP effect. To emphasize the base isolation effect, the non-isolated structural analysis results are added to graphics. The predominant frequencies of bridge non-isolated, isolated with SCFP and isolated with TCFP conditions decreased from 0.849Hz to 0.497Hz and 0.338Hz, respectively. The maximum vertical displacements are obtained as 57cm, 54cm and 44cm for non-isolated, isolated with SCFP and isolated with TCFP conditions, respectively. The maximum vertical displacement reduction between isolated with TCFP bearing and isolated with SCFP bearing bridge is %23. Maximum axial forces are obtained as 60619kN, 18728kN and 7382kN, maximum shear forces are obtained as 23408kN, 17913kN and 16249kN and maximum torsional moments are obtained as 24020kNm, 7619kNm and 3840kNm for non-isolated, isolated with SCFP and isolated with TCFP conditions, respectively.
AtıfScopus5WoS4OpenAlex3İncele - MakaleAçık Erişim2014Scopus SJRQ1Nonlinear dynamic analysis of base isolated cable-stayed bridge under earthquake excitations
Atmaca, Barbaros; Yurdakul, Muhammet; Ateş, Şevket
In this paper, it is aimed to determine the earthquake effects on cable-stayed bridge isolated by single concave friction pendulum bearings (SCFP). In this context, Manavgat cable-stayed bridge is selected as a numerical application. The selected bridge has 202. m composite deck and 42. m steel tower. 3D finite element models (FEM) of the base isolated and non-isolated bridge are modeled by using SAP2000. Three different earthquakes which are 11 December 1999 Düzce, 23 November 2011 Van and 13 March 1992 Erzincan earthquakes are subjected to the 3D FEM models in order to determine the seismic behavior of the bridges. BOL-090 and BOL-000; ERCIS-EW and ERCIS-NS; ERZ-NS and ERZ-EW components of ground motions obtained from PEER and AFAD are applied to the bridges at the longitudinal and transverse directions, respectively. Nonlinear time history analysis is executed to determine the dynamic responses of the bridge. Comparison of dynamic behavior of isolated and non-isolated bridge with and without the SCFP bearings under three different earthquake motions has been conducted. The results obtained from analyses of 3D FEM of the bridge are presented by graphics and tables in detail. It is seen that using of isolation system reduces the destructive effects of earthquakes on the bridge.
AtıfScopus36WoS28OpenAlex36İncele - MakaleAçık Erişim2014Scopus SJRQ4Students' views on distance learning in Turkey: An example of Anadolu University open education faculty
Gurbuz, Fatih
The aim of the study is to reveal the students' views who are studying in different departments of distant education programs provided by Anadolu University in TURKEY. Qualitative research method was used in the study and purposeful sampling was followed. The research was conducted with 10 students who were working in different jobs and taking distance education courses in different departments. The interviews carried out face to face with the participants by the researcher were recorded by getting their consents. The interview data recorded were later transcribed. Then the texts were given to the participants and the recordings were verified for their accuracy and completeness, so the reliability of data was obtained. Content analysis method was used for the data analysis. When the findings obtained as a result of data analysis were examined, the students taking distance education courses in different departments stated that this education method was a great opportunity and chance for them. Moreover, it was determined that the participant students in the study had positive attitudes and views towards distance education, but they had some negative views such as lack of course materials.
AtıfScopus8WoS3OpenAlex44İncele - MakaleAçık Erişim2014Scopus SJRQ1A fuzzy DEMATEL-based solution approach for facility layout problem: A case study
Altuntas, Serkan; Selim, Hasan; Dereli, Turkay
Facility layout in production systems is a difficult activity since both qualitative and quantitative factors affect the location decision, and also influence and causal relationship between these factors should be determined for a better location. In this respect, it is demonstrated in this study that fuzzy decision-making trial and evaluation laboratory (fuzzy DEMATEL) method can effectively be used in handling facility layout problems in practice. The qualitative factors that described by linguistic terms can be taken into account through fuzzy structure of the method. Considering this, a fuzzy DEMATEL-based solution approach for facility layout problem is proposed in this study. The proposed approach takes into account both qualitative and quantitative location factors. To address the need in practice, six important location factors are considered in this study. These are material flow, information flow, personnel flow, equipment flow, environmental condition, and supervision of personnel. This study differs from the previous works in that it applies fuzzy DEMATEL method to facility layout problem. To explore the viability of the proposed approach, a real world problem in a machinery industry firm is handled.
AtıfScopus65WoS46OpenAlex59İncele