Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Yildiz, Salih(5)
- Karsli, Orhan(4)
- Uk, Zuhal Cilingir(4)
- Adanur, Süleyman(3)
- Bayraktar, Alemdar(3)
- Dokuz, Abdurrahman(3)
- Kandemir, Raif(3)
- Kucuk, Haydar(3)
- Küçük, Haydar(3)
- Uysal, Ibrahim(3)
- Wijbrans, Jan(3)
- Ayaydin, Hasan(2)
- Aydin, Faruk(2)
- Bahar, Bilge(2)
- Bayram, Bahri(2)
- Bilici, Ahmet(2)
- Cengiz, Ekrem(2)
- Chen, Bin(2)
- Gedikli, Hasan(2)
- Gumus, Mahmut(2)
- Kantekin, Halit(2)
- Kaya, Elif Celenk(2)
- Kefeli, Umut(2)
- Kurtuldu, Hüseyin Sabri(2)
- Merdan, Mehmet(2)
- Nazir, Bayram(2)
- Oncel, Mustafa(2)
- Sadiklar, M. Burhan(2)
- Salepci, Taflan(2)
- Sipahi, Ferkan(2)
- Topal, Umut(2)
- Uzman, Ümit(2)
- Yetgin, Şükrü(2)
- Yildirim, Emre(2)
- Yildirim, Mehmet(2)
- Çavdar, Ahmet(2)
- Çavdar, Özlem(2)
- Özbek, Mehmet Ferhat(2)
- Özdemir, Atilla(2)
- Akbulut, Omer(1)
Yayınlar
- MakaleYalnız künye2010Investigation of abrasion resistance of cement mortar with different pozzolanic compositions and subjected to sulfated medium
Çavdar, Ahmet; Yetgin, Şükrü
The durability phenomenon for concrete, or cement mortar, has gained attention recently as one of the important mechanical properties. It can be described as concrete's resistance to the destructive influences of a medium containing acid, sulfate and/or various chemicals and mechanical effects, like abrasion. Most of the studies attempted to improve these individual properties in concrete. However, concrete can be subjected to two or more of these effects simultaneously. In this study, the mortars produced with cement samples having seven different compositions and varied with an air-entraining agent were subjected to the influence of sulfate and abrasive effects simultaneously. In this study, several examples were evaluated using samples cured for six different periods throughout one year. This study is supported by thin section and XRPD investigations, in addition to being subjected to the basic tests, such as compression, flexure and abrasion. If the most important findings obtained from the study are summarized, it is seen that a compact cement matrix is more effective against both sulfate and abrasive effects than mineral additives. The mortars subjected to coupled (sulfate and abrasive) effects show less durability if compared to ones cured in water and later abraded.
- MakaleAçık Erişim2010Effect of rectangular/circular cutouts on thermal buckling load optimization of angle-ply laminated thin plates
Topal, Umut; Uzman, Ümit
This paper deals with thermal buckling load optimization of symmetrically laminated angle-ply thin plates with centrally located different cutouts subjected to a uniform temperature load rise. The optimum results are given for maximum buckling temperature and the fibre orientation is adopted as design variable. The results are obtained for the various cutout geometries such as rectangle and circle. The modified feasible direction (MFD) method is used for the optimization routine. Therefore a program based on FORTRAN is used. Finally, the effects of cutout areas, plate aspect ratios and boundary conditions on the optimum results are demonstrated.
- MakaleYalnız künye2010Comparison of stepped and smooth spillway effects on stream reaeration
Aras, Egemen; Berkun, Mehmet
The oxygen transfer at a hydraulic structure happens by self-aeration through the spillway and by flow aeration in the hydraulic jump downstream of the hydraulic structure. Spillways with their water-air controlling mechanisms are important not only for their structural properties but also for their effects on stream ecology. Spillway types also affect the efficiency of aeration. Decisions on the types of spillway should be made by taking the environmental conditions and flow rates into consideration. This paper compares the aeration efficiency of stepped and smooth spillways. Empirical correlations predicting length of the non-aerated flow region and aeration efficiency are developed. Smooth and stepped spillways cause increased dissolved oxygen (DO) concentrations at the downstream part of the channel. DO concentration changes are shown to depend on the flow types, discharge rates, tail-water depth and travelling times.
- MakaleYalnız künye2010Stochastic finite element analysis of a cable-stayed bridge system with varying material properties
Çavdar, Özlem; Bayraktar, Alemdar; Adanur, Süleyman
Stochastic seismic finite element analysis of a cable-stayed bridge whose material properties are described by random fields is presented in this paper. The stochastic perturbation technique and Monte Carlo simulation (MCS) method are used in the analyses. A summary of MCS and perturbation based stochastic finite element dynamic analysis formulation of structural system is given. The Jindo Bridge, constructed in South Korea, is chosen as a numerical example. The Kocaeli earthquake in 1999 is considered as a ground motion. During the stochastic analysis, displacements and internal forces of the considered bridge are obtained from perturbation based stochastic finite element method (SFEM) and MCS method by changing elastic modulus and mass density as random variable. The efficiency and accuracy of the proposed SFEM algorithm are evaluated by comparison with results of MCS method. The results imply that perturbation based SFEM method gives close results to MCS method and it can be used instead of MCS method, especially, if computational cost is taken into consideration.
- MakaleYalnız künye2010Sources and petrogenesis of Jurassic granitoids in the Yusufeli area, Northeastern Turkey: Implications for pre- and post-collisional lithospheric thinning of the eastern Pontides
Dokuz, Abdurrahman; Karsli, Orhan; Chen, Bin; Uysal, Ibrahim
Small granitoids emplaced into the early Jurassic volcani-clastic succession in the Yusufeli area, northeastern Turkey, can be temporally and geochemically classified into two groups: early Jurassic low-K and late Jurassic high-K. 40Ar-39Ar hornblende analyses yielded 188.0 ± 4.3 Ma for the Dutlupi{dotless}nar intrusion, dating the subduction related rifting in the region. It comprises metaluminous to weakly peraluminous (ASI = 0.94-1.11) granodiorite and, to a lesser extent, tonalite whose K2O-poor (< 2.04 wt.%) nature and weak negative Eu anomalies (Eu/Eu* = 0.9-0.7) preclude derivation by fractional crystallization from a K-rich melt. Sr, Nd and Pb isotopic data reveal derivation by partial melting from an already cooled tholeiitic basic rocks which had mantle-like isotope signature. The Sumbated intrusion formed in the late Jurassic (153.0 ± 3.4 Ma) and consists chiefly of metaluminous (ASI = 0.84-0.99) quartz monzodiorite. Medium to high-K2O, relatively high MgO and Sr contents, flat HREE patterns without prominent Eu anomalies, slightly positive εNd(t) values (+ 1.5 to + 2.5) and low ISr ratios (0.7046-0.7056) are consistent with an origin by dehydration melting of a juvenile source, above the garnet stability field, dominated by likely K-amphibole bearing calc-alkaline mafic rocks. Geochemical data show that fractional crystallization from a Sumbated-like quartz monzodioritic magma is the fundamental process responsible for the evolved compositional range of the Keçikaya intrusion. The geochemical and geochronological data presented here indicate that the late Jurassic magmatism occurred in a post-collisional setting. Slab-breakoff, which was followed by shortly after collision, seems to be the most plausible mechanism for the generation of medium to high-K calc-alkaline rocks of the Sumbated and the Keçikaya intrusions, indicating a switch in the geodynamic setting, e.g., from pre-collision to post-collision in the middle Jurassic in the eastern Pontides.
- BildiriAçık Erişim2010Assessment of Turkish and class teacher candidate's attitudes towards children's literature and children's literature lesson
Ulaş, A. Halim; Kolaç, Emine; Topal, Yakup; Sevim, Oǧuzhan; Keser, H; Ozcinar, Z; Kanbul, S
Purpose of this research is to reveal class and Turkish teacher candidates' attitudes towards children's literature lesson, and works of children's literature. Study group of this research is comprised of students from Classroom Teaching and Turkish Teaching Departments of Faculty of Education of Atatürk University. Answers were sought for the level of classroom teaching and preschool teacher candidates' towards children's literature lesson, and works of children's literature, and whether there is any significant difference is seen in classroom teaching and pre-school teacher candidates' towards children's literature lesson, and works of children's literature in terms gender, and departments. Having the research conducted according to survey method (2007), "Attitude Scale towards Children's Literature, and Children's Literature Lesson", having been developed by ..., and comprised of 35 articles, was made use of. At the end of the research, it was concluded that teacher candidates had developed a positive attitude towards children's literature, and children's literature lesson, and neither gender, nor field differences had significantly affected that attitude.
- MakaleAçık Erişim2010Meibomian carcinoma of the eyelid in a Simmental cow
Gokhan, Nezihe; Sozmen, Mahmut; Ozba, Burhan; Gungor, Emine
Objective: To describe the clinical and pathomorphological features of meibomian carcinoma (MC) diagnosed in a Simmental cow. Material and methods: A 7-year-old Simmental cow was admitted to the Veterinary Surgery Clinics of Faculty of Veterinary Medicine, University of Kafkas, Kars, Turkey. The signalment and anatomical distribution were summarized and focused on pathomorphological description. Results: Macroscopically, a papillary mass, 5 × 3.5 × 7 cm in size, arising from the left lower eyelid with local spread to the upper eyelid and covering the entire globe was observed. The mass was ulcerated and hemorrhagic and applied pressure to the globe. Following sedation and local anesthesia, the mass and globe were excised. Histopathological examination revealed an MC. Conclusions: The diagnosis of MC is infrequent in veterinary literature. Complete surgical excision could be curative and histopathology is crucial for the diagnosis of MC occurring in animals.
- MakaleYalnız künye2010Exergetic performance analysis of a recirculating aquaculture system
Kucuk, Haydar; Midilli, Adnan; Özdemir, Atilla; Çakmak, Eyüp; Dincer, Ibrahim
This paper examines exergetic aspects of a Recirculation Aquaculture System (RAS) for Black Sea trout (Salmo trutta labrax) fingerling rearing at the Trabzon Central Fisheries Research Institute, Turkey. In its thermodynamic analysis, each component of the RAS is treated as a steady-state steady flow system and its exergetic efficiencies are studied. In addition, the following parameters are measured and recorded in experiments: the mass flow rates, inlet and outlet temperatures and of the system components, surrounding temperatures, and electrical work utilized by the components in the RAS. Based on these experimental data, inlet and outlet exergy values, exergy losses, and exergetic efficiencies of each component in the system are determined to assess their performance. Moreover, the overall system exergy efficiency is determined. The results show that exergy efficiencies of the system components are highly affected by varying input exergy flows as a function of the surrounding temperature and chiller's operating period.