Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Bulut, Mesut(4)
- Demir, Nazan(4)
- Demir, Yasar(4)
- Birinci, Ahmet(3)
- Bute, Musa(3)
- Ertugrul, Mehmet(3)
- Hasar, Ugur Cem(3)
- Kaya, Yunus(3)
- Öner, Erdal(3)
- Adiguzel, Ahmet(2)
- Agar, Guleray(2)
- Altuntas, Serkan(2)
- Anar, Mustafa(2)
- Barroso, J.J.(2)
- Barroso, Joaquim José(2)
- Beydemir, Şükrü(2)
- Bute, M.(2)
- Cinar, M.(2)
- Cinar, Mehmet(2)
- Duran, Celal(2)
- Erdem, O.(2)
- Ertugrul, M.(2)
- Gulluce, Medine(2)
- Hasar, U.C.(2)
- Isik, Ceyhun(2)
- Kaban, Guzin(2)
- Kamiloglu, Aybike(2)
- Karabacak, M.(2)
- Karabacak, Mehmet(2)
- Kaya, Mukerrem(2)
- Kaya, Y.(2)
- Kizil, Hamit Emre(2)
- Laborda, JC(2)
- Maasoglu, Y(2)
- Nadaroglu, Hayrunnisa(2)
- Ozdamli, F(2)
- Ozdes, Duygu(2)
- Ozturk, K.(2)
- Sayin, Bilge(2)
- Serencam, Huseyin(2)
Yayınlar
- 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.
AtıfScopus19WoS11OpenAlex15
İncele - 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.
AtıfScopus20WoS20OpenAlex21
İncele - 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 - MakaleAçık Erişim2014Scopus SJRQ3Comparison of Levitation Forces of Bulk MgB2 Superconductors Produced by Nano Boron and Carbon-Doped Nano Boron
Duz, I.; Guner, S. B.; Erdem, O.; Demir, I.; Kapucu, V.; Çelik, S.; Ozturk, K.; Hossain, S.; Gencer, A.; Yanmaz, E.
MgB2 bulk superconductors were prepared by hot press plus furnace heating method. Two types of boron powders were used, one is amorphous nano boron and the other is C-doped boron. Characteristics of superconductors were determined by XRD and resistance measurements. Systematic levitation force measurements were performed by using a modular system at low temperatures. These bulk superconductors showed around 9 N repulsive and 4 N attractive forces in the z-axis at 20 K at closest point to the cryostat lid which contains the MgB2 superconductor. These values slightly decreased by increasing temperature to 24 and 28 K for both samples. Comparing two samples, nano boron MgB2 showed slightly higher levitation force than C-doped MgB2 although C-doped MgB2 has higher attractive force value at the closest point. This situation points out that C-doped MgB2 is much proper for attractive force applications (as guidance force) while the nanoboron MgB2 sample is much appropriate for repulsive force (as levitation).
AtıfScopus13WoS13OpenAlex17İncele