Koleksiyon/r/bayburt/10001

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Koleksiyondaki öğeler

  • MakaleYalnız künye2014Scopus SJRQ2
    Comparison 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.

    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    • SDG 11 · Sürdürülebilir Şehirler ve Topluluklar
    AtıfScopus5WoS4OpenAlex3
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2013Scopus SJRQ1
    Structure and biosynthesis of two exopolysaccharides produced by lactobacillus johnsonii FI9785

    Dertli, Enes; Colquhoun, Ian J.; Gunning, A. Patrick; Bongaerts, Roy J.; Le Gall, Gwénaëlle; Bonev, Boyan B.; Mayer, Melinda J.; Narbad, Arjan

    Exopolysaccharides were isolated and purified from Lactobacillus johnsonii FI9785, which has previously been shown to act as a competitive exclusion agent to control Clostridium perfringens in poultry. Structural analysis by NMR spectroscopy revealed that L. johnsonii FI9785 can produce two types of exopolysaccharide: EPS-1 is a branched dextran with the unusual feature that every backbone residue is substituted with a 2-linked glucose unit, and EPS-2 was shown to have a repeating unit with the following structure: -6)-α-Glcp-(1-3)-β-Glcp-(1-5)-β-Galf-(1-6)-α-Glcp-(1-4) -β-Gal p-(1-4)-β-Glcp-(1-. Sites on both polysaccharides were partially occupied by substituent groups: 1-phosphoglycerol and O-acetyl groups in EPS-1 and a single O-acetyl group in EPS-2. Analysis of a deletion mutant (δepsE) lacking the putative priming glycosyltransferase gene located within a predicted eps gene cluster revealed that the mutant could produce EPS-1 but not EPS-2, indicating that epsE is essential for the biosynthesis of EPS-2. Atomic force microscopy confirmed the localization of galactose residues on the exterior of wild type cells and their absence in the δepsE mutant. EPS2 was found to adopt a random coil structural conformation. Deletion of the entire 14-kb eps cluster resulted in an acapsular mutant phenotype that was not able to produce either EPS-2 or EPS-1. Alterations in the cell surface properties of the EPS-specific mutants were demonstrated by differences in binding of an anti-wild type L. johnsonii antibody. These findings provide insights into the biosynthesis and structures of novel exopolysaccharides produced by L. johnsonii FI9785, which are likely to play an important role in biofilm formation, protection against harsh environment of the gut, and colonization of the host.

    AtıfScopus131WoS120OpenAlex134
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  • MakaleAçık Erişim2015Scopus SJRQ2
    Direct and fast growth of GaAs thin films on glass and polyethylene terephthalate substrates using a thermionic vacuum arc

    Pat, Suat; Korkmaz, Şadan; Özen, Soner; Şenay, Volkan

    Using a thermionic vacuum arc, single‐crystal gallium arsenide (GaAs) layers of micron thickness were grown on PET and glass substrates in 2 min. We present a new deposition mechanism and parameters for GaAs thin films produced in a very short time. Crystal direction was found to be (111) plane for the GaAs/PET sample and (022) plane and (133) plane for the GaAs/glass sample, respectively. The average roughness values of the deposited thin films were determined to be approximately 30 nm for GaAs/PET and 60 nm for GaAs/glass. The structures can be seen clearly in field emission scanning electron microscopy and atomic force microscopy. The obtained optical band is nearly the same with literatures values of the GaAs. Although produced structures in different crystal formations, only aggregations dimensions and absorbance of the layers were changed. Obtained refractive index values are nearly same with database info.

    AtıfScopus16WoS18OpenAlex16
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  • MakaleYalnız künye2017Scopus SJRQ2
    The Al doping effect on the surface, optical, electrical and nanomechanical properties of the ZnO and AZO thin films prepared by RF sputtering technique

    Pat, Suat; Mohammadigharehbagh, Reza; Özen, Soner; Şenay, Volkan; Yudar, H. Hakan; Korkmaz, Şadan

    In this study, ZnO and aluminum doped ZnO (AZO) thin films were deposited at constant RF power of 100 W for the determine of the structural, surface, optical, electrical and nanomechanical properties. X–Ray diffraction (XRD), atomic force microscopy (AFM), nanoindentation technique and UV–Vis spectrophotometer were used. ZnO (100) and ZnO (004) orientations were detected in the ZnO and AZO films. The crystallite size values for the films were calculated as to be as 35 nm and 20 nm for ZnO and AZO thin films, respectively. It was found that the roughness values decreased to 3.15 nm from 5.15 nm for AZO and ZnO films, respectively. The hardness values of the ZnO and AZO thin films are measured as 7 GPa and 11 GPa. Young's modulus values were determined as 155 GPa and 95 GPa for ZnO and AZO films, respectively. The ZnO and AZO thin films have high transparency.

    AtıfScopus50WoS50OpenAlex57
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  • MakaleAçık Erişim2013Scopus SJRQ2
    Experimental research of dynamic instabilities in the presence of coiled wire inserts on two-phase flow

    Omeroglu, Gokhan; Comakli, Omer; Karagoz, Sendogan; Sahin, Bayram

    The aim of this study is to experimentally investigate the effect of the coiled wire insertions on dynamic instabilities and to compare the results with the smooth tube for forced convection boiling. The experiments were conducted in a circular tube, and water was used as the working fluid. Two different pitch ratios (H / D = 2.77 and 5.55) of coiled wire with circular cross-sections were utilised. The constant heat flux boundary condition was applied to the outer side of the test tube, and the constant exit restriction was used at the tube outlet. The mass flow rate changed from 110 to 20 g/s in order to obtain a detailed idea about the density wave and pressure drop oscillations, and the range of the inlet temperature was 15-35°C. The changes in pressure drop, inlet temperature, amplitude, and the period with mass flow rate are presented. For each configuration, it is seen that density wave and pressure drop oscillations occur at all inlet temperatures. Analyses show that the decrease in the mass flow rate and inlet temperature causes the amplitude and the period of the density wave and the pressure drop oscillations to decrease separately.

    AtıfScopus2WoS1OpenAlex4
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  • MakaleYalnız künye2018Scopus SJRQ2
    The interactions of cephalosporins on polyol pathway enzymes from sheep kidney

    Şengül, Bülent; Beydemir, Şükrü

    Context: Cephalosporins are derived from the fungus Acremonium. Due to their strong bactericidal ability, these drugs have to a wide usage in medicine. Objective: An investigation of the effects on sheep renal aldose reductase (AR) and sorbitol dehydrogenase (SDH) of cefoperazone, cefazolin, cefuroxime, ceftazidime and ceftriaxone as cephalosporin drugs was carried out in the present study. Methods: AR and SDH were purified from sheep kidney by ion exchange, gel filtration and affinity methods with approximately 219- and 484-fold, respectively. Some kinetic properties of the enzymes were determined such as optimal pH, optimal ionic strength, optimal temperature, stable pH, Km and Vmax. IC50 values of the drugs were found for each enzyme. Results: While the AR was inhibited by all drugs, SDH enzyme was inhibited by only CXM (IC50 8.10 mM). Interestingly, CZO activated SDH enzyme. This result was evaluated as important for the flow of the polyol reactions. Ki values and inhibition types were determined for AR. However, these values could not have determined for SDH, due to insufficient inhibition. Conclusions: From these results, it was concluded that cephalosporins may have an important effect on flow of the polyol metabolism.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus12WoS12OpenAlex13
    ScopusWeb of SciencePubMedİncele
  • MakaleAçık Erişim2018Scopus SJRQ3
    The anti-genotoxic effect of some lichenic acids

    Kizil, Hamit Emre; Ceker, Selcuk; Capik, Ozel; Agar, Guleray

    Four lichen secondary metabolites; diffractaic acid, lecanoric acid, lobaric acid and vulpinic acid were evaluated for the anti-genotoxic effects on human lymphocytes in vitro using single cell gel electrophoresis (SCGE) or comet assay. Carbon tetrachloride, a known mutagenic agent was used as the positive control in the comet test system. The results revealed that at all concentrations, the tested compounds mediated a significant decrease in total DNA damage (comet assay) as compared with positive controls (p > 0.05). The most effective doses of lichen acids were found to be 100 μgmL-1 of diffractic acid, lobaric acid and vulpinic acid, and 50 μgmL-1 of lecanoric acid. In addition, it was determined that the most effective among the tested compounds was vulpinic acid.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus4WoS2OpenAlex2
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  • Kitap BölümüYalnız künye2016
    Investigation of the effect of canola methyl ester on cyclic variation using wavelet analysis method

    Efe, Şükran; Ceviz, M.A.

    Diesel engines are the most commonly used internal combustion engine in transportation, power generation, and other industries. Combustion in the diesel engines takes place at high temperatures due to the high compression ratio, and therefore high energy is obtained when diesel fuel is used. But the most commonly used alternative fuel diesel engines is biodiesel today. The market share of biodiesel is on the rise because of the increasing damage of diesel and decreasing oil reserves to the environment. In this study, cyclic variation that occurred when canola biodiesel (canola methyl ester) that is produced by transesterification method was used as diesel fuel was investigated. Three different biodiesel ratios, B20, B50, and B100 were used in the study. In interpretation cyclic variations wavelet analysis method is used and all results are compared with diesel fuel. It is concluded that the use of biodiesel in diesel engines has positive effect on cyclic variation and this effect increases with the increasing ratio of biodiesel in the mixture.

    • SDG 7 · Erişilebilir ve Temiz Enerji
  • MakaleAçık Erişim2017Scopus SJRQ1
    Effect of high pressure homogenization (HPH) on microstructure and rheological properties of hazelnut milk

    Gul, Osman; Saricaoglu, Furkan Turker; Mortas, Mustafa; Atalar, Ilyas; Yazici, Fehmi

    The effect of high pressure homogenization (HPH) on microstructure and rheological properties of hazelnut milks was investigated. Hazelnut milk samples were produced from cold pressed hazelnut cake and homogenized up to 150 MPa pressure. Microstructural and rheological properties of products, except temperature sweep, were greatly affected by HPH treatments. Homogenized samples showed significant reduction in particle size, which turned from bimodal and poly-disperse to monodisperse distributions. HPH decreased the consistency of products from 91.82 to 0.51 Pa.sn and increased flow behavior index from 0.15 to 0.36. All samples showed higher values G′ than G″, which indicates that samples could be classified as soft-gel network, and hazelnut milk samples did not obey the Cox-Merz rule without multiplying angular frequency with shift factor. In conclusion, HPH can be used to reduce the consistency of samples and the friction loss, thus minimizing the amount of energy required to flow during processing and distribution. Industrial relevance. Vegetable based beverages are available at any supermarket as an alternative to dairy products with an increasing consumer acceptance. Between these beverages hazelnut milk samples are the most noteworthy products due to important role in human nutrition and health, and moreover due to well accepted and widely consumed product. Due to its composition, hazelnut milks have very high consistency, and therefore, the energy consumption for processing and handling is too high. In this research, the high pressure homogenization (HPH) technology was successfully proposed to be used for improving microstructural properties, and hence reducing its consistency. The energy consumption during processing and distribution can be minimized by reducing the consistency and friction losses of product.

    • SDG 2 · Açlığa Son
    AtıfScopus97WoS80OpenAlex100
    ScopusWeb of Scienceİncele
  • BildiriAçık Erişim2018Scopus SJRQ3
    Room temperature superplasticity in fine/ultrafine-grained Zn-Al alloys with different phase compositions

    Demirtas, Muhammet; Yanar, Harun; Saray, Onur; Purcek, Gencaga

    Three Zn-Al alloys, namely Zn-22Al, Zn-5Al and Zn-0.3Al, were subjected to equal-channel angular pressing (ECAP), and the effect of ECAP on their microstructure and room temperature (RT) superplastic behavior were investigated in detail referring to previous studies reported by the authors of the current study. ECAP remarkably refined the microstructures of three alloys as compared to their pre-processed conditions. While the lowest grain size was achieved in Zn-22Al alloy as 200 nm, the grain sizes of Zn-5Al and Zn-0.3Al alloys were ~540 nm and 2 µm, respectively, after ECAP. After the formation of fine/ultrafine-grained (F/UFG) microstructures, all Zn-Al alloys exhibited superplastic behavior at RT and high strain rates. The maximum superplastic elongations were 400%, 520% and 1000% for Zn-22Al, Zn-5Al and Zn-0.3Al alloys, respectively. It is interesting to point out that the highest RT superplastic elongation was obtained in Zn-0.3Al alloy with the largest grain size, while Zn-22Al alloy having the lowest grain size showed the minimum superplastic elongation. This paradox was attributed to the different phase compositions of these alloys. The formation of Al-rich α/α phase boundaries, where grain boundary sliding is minimum comparing to Zn-rich η/η and η/α phase boundaries of Zn-Al alloys, is the lowest level in Zn-0.3Al alloy among all the alloys. Therefore, it can be concluded that if it is desired to achieve high superplastic elongation in Zn-Al alloys at RT, keeping Al content at a possibly minimum level seems to be the most suitable way.

    AtıfScopus6OpenAlex5
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  • Derleme MakaleYalnız künye2016Scopus SJRQ1
    Renewable and sustainable energy saving strategies for greenhouse systems: A comprehensive review

    Cuce, Erdem; Harjunowibowo, Dewanto; Cuce, Pinar Mert

    In this study, a comprehensive review focusing on key strategies of energy saving and climate control technologies for greenhouses is presented. Following the brief and concise assessment of existing greenhouse systems in terms of their role in total energy consumption; cost-effective, energy-efficient and environmentally friendly technologies are analyzed in detail for potential utilization in greenhouses for notable reductions in energy consumption and emission levels. The technologies considered within the scope of this research are mainly renewable and sustainable based solutions such as photovoltaic (PV) modules, solar thermal (T) collectors, hybrid PV/T collectors and systems, phase change material (PCM) and underground based heat storage techniques, energy-efficient heat pumps, alternative facade materials for better thermal insulation and power generation (heat insulation solar glass, PV glazing, aerogel and vacuum insulation panel, polycarbonate sandwich panels), innovative ventilation technologies using pre-heating and cooling (high performance windcatchers) and efficient lighting systems. The findings from the research clearly reveal that up to 80% energy saving can be achieved through appropriate retrofit of conventional greenhouses with a payback period of 4-8 years depending on climatic conditions and crop type.

    • SDG 2 · Açlığa Son
    • SDG 7 · Erişilebilir ve Temiz Enerji
    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    • SDG 12 · Sorumlu Üretim ve Tüketim
    • SDG 13 · İklim Eylemi
    AtıfScopus354WoS302OpenAlex382
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2017Scopus SJRQ1
    Potential application of high pressure homogenization (HPH) for improving functional and rheological properties of mechanically deboned chicken meat (MDCM) proteins

    Saricaoglu, Furkan Turker; Gul, Osman; Tural, Serpil; Turhan, Sadettin

    The potential application of high pressure homogenization (HPH) for modifying the solubility, emulsifying and foaming properties, particle size distributions, zeta potential and rheological properties of mechanically deboned chicken meat (MDCM) proteins was evaluated. HPH decreased particle size, produced higher zeta potential and stronger electrostatic repulsion, and hence, improved water solubility, as well as emulsifying, foaming properties, flow ability and dynamic shear properties of protein suspensions. Steady and dynamic shear results indicated that samples had shear-thinning and soft-gel network behavior due to higher G′ than G″. Creep and recovery tests were explained with Burgers and exponential decay models, respectively, and led to a better understanding the internal structure, as well as elastic and viscous behavior. The final percentage recovery increased as homogenization pressure increased due to strengthened solid-like structure of protein suspensions. These results revealed that HPH can be a valuable process to improve functional and rheological properties of MDCM proteins.

    AtıfScopus53WoS51OpenAlex56
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2015Scopus SJRQ2
    MAC protocols for energy harvesting wireless sensor networks: Survey

    Kosunalp, Selahattin

    Energy harvesting (EH) technology in the field of wireless sensor networks (WSNs) is gaining increasing popularity through removing the burden of having to replace/recharge depleted energy sources by energy harvester devices. EH provides an alternative source of energy from the surrounding environment; therefore, by exploiting the EH process, WSNs can achieve a perpetual lifetime. In view of this, emphasis is being placed on the design of new medium access control (MAC) protocols that aim to maximize the lifetime of WSNs by using the maximum possible amount of harvested energy instead of saving any residual energy, given that the rate of energy harvested is greater than that which is consumed. Various MAC protocols with the objective of exploiting ambient energy have been proposed for energy-harvesting WSNs (EH-WSNs). In this paper, first, the fundamental properties of EH-WSN architecture are outlined. Then, several MAC protocols proposed for EH-WSNs are presented, describing their operating principles and underlying features. To give an insight into future research directions, open research issues (key ideas) with respect to design trade-offs are discussed at the end of this paper.

    • SDG 7 · Erişilebilir ve Temiz Enerji
    AtıfScopus56WoS45OpenAlex57
    ScopusWeb of Scienceİncele
  • BildiriAçık Erişim2017
    The speed control of DC motor under the load condition using PI and PID controllers

    Corapsiz, Muhammed Reşit; Kahveci, Hakan

    In this study, it was aimed to compare PI (Proportional-Integral) and PID (Proportional-Integral-Derivative) controllers for speed control of Permanent Magnet Direct Current (PMDC) motor under both load and without load. For this purpose, firstly, the mathematical model was obtained from the dynamic equations of the PMDC motor and the obtained mathematical model was transferred to the simulation environment and modeled using Matlab/SIMULINK. Following the modeling process, PI and PID controller structures were formed, respectively. Secondly, after these structures were formed, the PMDC motor was run without any controller. Then, the control of the PMDC motor with no load was provided by using PI and PID controllers. Finally, the PMDC motor were loaded under the constant load (TL = 3 N.m.) for each condition and selected time period (t = 3 s). The obtained result for each control operations was comparatively given by observing effects of loading process on systems. When the obtained results were evaluated for each condition, it was observed that PID controller have the best performance with respect to PI controller.

    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    AtıfScopus3OpenAlex4
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2014Scopus SJRQ1
    Nonlinear 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.

    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    • SDG 11 · Sürdürülebilir Şehirler ve Topluluklar
    AtıfScopus36WoS28OpenAlex36
    ScopusWeb of Scienceİncele
  • BildiriYalnız künye2017
    Antiproliferative and apoptotic effects of diffractaic acid in A549 and AGS cancer cells

    Klzll, Hamit Emre; Aǧar, Güleray

    In this study, we determined the antiproliferative and apoptotic effects of diffractaic acid by measuring the gene expression changes of topo II α, caspase-3 and p53 on A549 and AGS cancer cells. Real time PCR assay was used to measure the change folds. It was determined that concentrations of 12,5, 50 and 100μg / ml were antiproliferative and apoptotic for the A549 cancer cell line and 50μg / ml for the AGS cell line.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus2WoS1OpenAlex2
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2018Scopus SJRQ2
    Chemical characterization of 64 propolis samples from hakkari, Turkey

    Bayram, Nesrin Ecem; Sorkun, Kadriye; Öz, Gül Cevahir; Salih, Bekir; Topçu, Gülaçtı

    Propolis is a resinous substance produced by honey bees from various plants they visit. Sixty-four propolis samples were collected from different localities of four districts (Merkez, Yüksekova, Şemdinli, and Çukurca) in Hakkari territory. Ethanol extracts of the propolis samples were prepared, and their chemical contents were determined by gas chromatography–mass spectroscopy (GC–MS). Flavonoids were generally found in a high concentration in Şemdinli samples of Turkey. Twenty-seven coumarins were identified in the 28 propolis samples among studied 64 ones. Except suberosin, the coumarins were never reported before in any propolis sample with Turkish origin. The propolis samples belonging to Yüksekova were found to be richer in coumarins than the others, and the most richest one among the Yüksekova apiaries, was found to be Akocak sample (Y2) with 41.99% total yield, followed by Akçalı sample (Y5) (30.86%). This is a first comprehensive and original report about the chemical profile of propolis samples from Hakkari. The propolis samples from Hakkari exhibited a chemical content rich in flavonoids including coumarins and furocoumarins.

    AtıfScopus16WoS14OpenAlex23
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  • MakaleAçık Erişim2014Scopus SJRQ4
    Students' 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.

    • SDG 4 · Nitelikli Eğitim
    AtıfScopus8WoS3OpenAlex44
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2013Scopus SJRQ2
    Determination of conformational and spectroscopic features of ethyl trans-alfa-cyano-3-indole-acrylate compound: An experimental and quantum chemical study

    Cinar, Mehmet; Karabacak, Mehmet

    The optimized geometrical structure, vibrational and electronic transitions, chemical shifts and non-linear optical properties of ethyl trans-alfa-cyano-3-indole-acrylate (C14H12N 2O2) compound were presented in this study. The ground state geometrical structure and vibrational wavenumbers were carried out by using density functional (DFT/B3LYP) method with 6-311++G(d,p) as basis set. The vibrational spectra of title compound were recorded in solid state with FT-IR and FT-Raman in the range of 4000-400 cm-1 and 4000-10 cm -1, respectively. The fundamental assignments were done on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. The 1H, 13C and DEPT NMR spectra were recorded in DMSO solution, and gauge-invariant atomic orbitals (GIAO) method was used to predict the isotropic chemical shifts. The UV-Vis absorption spectra of the compound were recorded in the range of 200-800 nm in various solvents of different polarity (acetone, benzene, chlorobenzene, chloroform, DMSO, ethanol, methanol and toluene). Solvent effects were calculated using TD-DFT and CIS method. To investigate the non-linear optical properties, the polarizability, anisotropy of polarizability and molecular first hyperpolarizability were computed. A detailed description of spectroscopic behaviors of compound was given based on the comparison of experimental measurements and theoretical computations.

    AtıfScopus12WoS11
    ScopusWeb of SciencePubMedİncele
  • Kitap BölümüYalnız künye2017
    Analysis of structures by total potential optimization using meta-heuristic algorithms (TPO/MA)

    Toklu, Y.C.; Toklu, N.E.

    Use of meta-heuristic algorithms in analysis of structures is much more recent than their use in design of structures. Effectively, while design optimization makes use of genetic algorithms, simulated annealing, swarm optimization, etc. since about half a century with an increasing interest, these techniques are being used in structural analysis since a decade only. Total Potential Optimization using Meta-heuristic Algorithms (TPO/MA), though being an emerging method at the moment, has proved to be very efficient in solving nonlinear problems, involving both material and geometric nonlinearities. The capabilities of the method in treating under-constrained problems and problems with non-unique solutions are much more advanced than the classical methods including the well-known Finite Element Method.