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Koleksiyondaki öğeler
- BildiriYayıncıda açık erişim2016Scopus SJRQ1Determination of antigenotoxic, proliferative and cytotoxic properties of ellagic acid
Ceker, S.; Agar, G.; Anar, M.; Kizil, H. E.
- MakaleYalnız künye2010Scopus SJRQ2DETERMINATION OF ALKALI-SILICA REACTION EFFECTS OF ZEOLITIC TUFF ADDITION ON THE DIFFERENT AGGREGATES
Gökçe, H. Suleyman; Taban, Saniye; Simsek, Osman
The aim of this study is to determine the alkali-silica reaction (ASR) related characteristics of crushed stones that are produced from rocks of perlite, andesite and limestone when zeolitic tuff (ZT) is used in the mortar mix as cement replacement in different ratios. Accelerated mortar bar experiments in accordance with ASTM C 1260 were carried out on crushed stone aggregate samples to determine the ASR. CEM I 42.5 R type cement was replaced by ZT material in the following ratios: 0, 10, 20, 30 and 40%; in order to investigate the effects of replacement on the ASR pertaining to the aggregate types, 45 mortar bar pieces were produced. The length change values of the samples were measured on the 3, 7, 14, 28, 42, 56 days according to the accelerated mortar bar method. Measured length changes for the control samples on 14(th) day were found to be 0.570% at the level of potentially harmful for perlite, 0.101% at the level of critic for andesite and 0.061% at the level of harmless for limestone. Length changes at the harmful levels were taken under control for perlite at 30 and 40%, for andesite at 20, 30 and 40% ZT replacement ratios. Length change values of all samples decrease as ZT replacement increases. As a result, ZT replacement is effective to suppress the ASR of reactive aggregates.
AtıfWoS5
İncele - MakaleYalnız künye2015DAMAGE DETECTION IN SIMULATED SPACE FRAMES USING GENETIC ALGORITHMS
Artar, Musa; Daloglu, Ayse T.
Genetic algorithms (GA) based finite element model updating are applied to predict damage location and severity in space frames. The changes in natural frequencies are used as dynamic indicators to describe damaged members. Objective functions including dynamic data provide minimization of dynamic differences between numerical model and simulated damaged model. The presence of damages in structural elements is identified by stiffness reduction as a reduction in modulus of elasticity. Reproduction, double-point crossover and mutation operators are used in GA optimization procedures. In this paper, different simulated examples having various damage scenarios are modelled in SAP2000 software to obtain the experimental dynamic data. In the last example, noise effect is taken into account in simulated damaged data. A program is developed in MATLAB software for numerical model updating based on all genetic algorithm procedures. Thus, the size and extent of simulated damages are determined by updated numerical model. Results obtained from examples show that GA optimization is a convenient method for damage identification.
AtıfWoS2İncele - BildiriYalnız künye2015SOLID STATE BATTERY MANUFACTURING WITH THERMIONIC VACUUM ARC AND RF SPUTTERING
Pat, Suat; Özen, Soner; Senay, Volkan; Korkmaz, Sadan; Pat, Zerrin
AtıfWoS1İncele - MakaleAçık Erişim2026Statistical and qualitative analysis of ChatGPT and human raters in preservice teachers' writing assessment
Gülden, Bahadir; Bilge, Huzeyfe; Uysal, Pinar Kanik
Teachers spend a significant amount of time providing feedback. This study compared expert and ChatGPT assessments and feedback on written texts to determine the suitability of AI for writing skill assessments that are time-consuming to assess and provide feedback. Three experts and ChatGPT graded 14 Turkish undergraduate students' assignments using rubric that included content, language use, vocabulary, organization, and mechanics, and justified their decisions. The study involved document review and triangulation, a qualitative design. In addition, an intraclass correlation coefficient was used to assess the consistency of the ChatGPT and the experts' scores. All feedback was qualitatively analyzed to identify the strengths and weaknesses of the experts and their similarities with ChatGPT. Experts and ChatGPT had moderate to weak consistency in the writing subscales, while good reliability was found in the total score. Experts excelled in 'explanatory feedback', 'interpretation' and 'experience', while ChatGPT excelled in 'automation and continuity' and 'data processing capacity'. Experts' weaknesses included 'limited time and energy' and 'comparison bias', while ChatGPT's weaknesses were 'ambiguous expressions' and 'repetition'. The study also found that experts and ChatGPT preferred to provide constructive and supportive feedback.
AtıfWoS1OpenAlex2
İncele - MakaleYalnız künye2017Scopus SJRQ1Active Earth Thrust Theory for Horizontal Granular Backfill on a Cantilever Wall with a Short Heel
Kamiloglu, Hakan Alper; Sadoglu, Erol
Cantilever retaining walls are earth-retaining structures commonly used in construction. Conventional methods used to determine the active earth thrust acting on a wall often neglect friction between the soil and wall. This study presents an analytical solution for determining the active earth thrusts acting on a cantilever retaining wall with a short heel and a shear key that supports granular backfill. Three different earth thrusts were considered to be acting on three different parts of the rear face of the wall; the thrusts were derived using the limit equilibrium method. The active earth thrust formulas were also simplified in terms of earth thrust coefficients, unit weight, and wall height. An algorithm was developed to obtain earth thrust coefficients depending on various wall dimensions and internal friction angles and to prepare graphs representing earth thrust coefficients and failure surface angles. The effects of wall dimensions and internal friction angles on the earth thrusts and failure surface angles were determined. Finally, the proposed method of determining earth thrust coefficients was compared with other approaches.
AtıfWoS21OpenAlex20İncele - BildiriYalnız künye2012SYSTEM COMPONENTS AND OPERATION CHARACTERISTICS OF ISTANBUL BRT
Yurdagül, Erman; Gerçek, Haluk
With a population over 13 million Istanbul is the largest city in Europe. Traffic congestion is by far the most important problem that lessens the quality of life of the residents. Currently 1.8 million automobiles choke its roads daily. The rapid increase in motor vehicles, more than eightfold since 1980, has coincided with a dramatic population and economic growth. As a result, Istanbul is now overwhelmed by a flood of people and vehicles, an inadequate road network and a public transport system that has been slow to develop. This paper presents an overall evaluation of the Bus Rapid Transit (BRT) System in Istanbul of which the first phase was opened in 2007 as a relatively high-speed, high-capacity public transport mode along one of the most congested traffic arterials in the city. Presently it carries about 600,000 passengers daily over a 44 km-long alignment with 33 stations. The paper focuses on system components and presents a comparison with some major BRT systems in the world. Moreover, operational characteristics of travel patterns and ridership are analyzed with the data collected from the surveys and operator of the system; Istanbul Electricity, Tramway and Tunnel General Management (IETT). This study concludes that although the Istanbul BRT System has some drawbacks regarding the running way, access to stations, fare structure and overloaded buses, it has resulted in considerable savings in commuters' travel time and CO2 emissions. Finally, some suggestions for solving the important problems of the system are presented.
- MakaleYalnız künye2015Scopus SJRQ4The Optimization of Multi-Storey Composite Steel Frames with Genetic Algorithm Including Dynamic Constraints
Artar, Musa; Daloglu, Ayse
Optimum design of the structures, in other words designing the structures with minimum weight is one of the major research areas in structural engineering. The priority during optimization process is to ensure whether the necessary conditions are satisfied or not. In this study, the optimization of steel frame systems is carried out for traditional and dynamic constraints by using a genetic algorithm that mimics the biological processes. The stress constraints are determined according to TS648-Turkish code for design and construction of steel structures. Furthermore, displacement constrains are considered in the optimization procedure. In addition, natural frequencies are incorporated as dynamic constraints. Optimum design of multi-story plane frames is obtained and comparisons with the results of previous studies are made. The same design processes are repeated for the case of frames with composite beams. A program is coded in MATLAB to carry out all these applications. Results obtained in the study for the frame systems are also verified by SAP2000. It is concluded that the weight of the frames with composite beams are fewer and the dynamic constraints affect the design.
AtıfWoS6İncele - MakaleAçık Erişim2017Scopus SJRQ2Microalgae production and biofuel from microalgae
Elcik, Harun; Çakmakci, Mehmet
Fossil fuel reserves which supplying a major portion of energy needs, are depleting rapidly, and its environmental damages increases day by day. Therefore, like all developed and developing countries, our country have focused on the use of renewable energy sources. Within this scope in the our country, it was aimed gain of renewable energy sources to economy, promotion of sustainable energy production, and protection of environmental. Recently, one of the growing importance of renewable energy sources is the biomass energy. As an biomass energy source, all vegetable and animal organic substances which the main components are comprising carbohydrate compounds can be used. In these energy sources, microalgae seem promising for biofuel production due to their many advantages such as they have high photosynthetic efficiency, high biomass production, and they grow quickly. From microalgae, by using biochemical methods electricity, ethanol, hydrogen, methane and biodiesel and thermochemical methods syngas, biochar, biodiesel and electricity can be produced. In this review article, isolation of microalgae, microalgal biomass production, the methods used to biomass harvesting, and the availability of microalgae as a source of raw materials for renewable biofuels were viewed.
AtıfWoS13OpenAlex11İncele - MakaleAçık Erişim2025Does Lrig1 expression have a relationship with ERBB1 and ERBB2 expression in schizophrenia?
Uzunçakmak, Sevgi Karabulut; Özcan, Halil; Aydin, Pelin; Halici, Zekai
Purpose: This study aims to investigate Lrig1 expression and to reveal the possible relationship between Lrig1, ERBB1 and ERBB2 in schizophrenia. Materials and Methods: In this study, peripheral blood samples of 70 schizophrenia patients and 60 healthy controls were used. Real Time PCR was applied for Lrig1, ERBB1 and ERBB2 gene expression analysis. Results: The level of Lrig1 mRNA was lower in the patients when compared to healthy controls. Expression levels of ERBB1 and ERBB2 were decreased in the patients versus in the healthy controls. According to the receiver operating characteristic curve analysis, the three genes had the power to discriminate the patients from the ERBB1 and ERBB2 expressions in the patients. in schizophrenia.
- MakaleYalnız künye2017Optimization of Pectin Extraction from Orange Pulp and Characterization of Compositional and Steady Shear Properties
Yilmaz, Mustafa Tahsin; Muslu, Asli; Karasu, Salih; Bozkurt, Fatih; Dertli, Enes
Pectin, which is one of the most important wastes of fruit juice industry, was extracted from orange pulp at optimum conditions (pH, time and temperature) and modified using pectinase. The effect of modification on the structural properties of pectin was monitored using Fourier transformed infrared spectroscopy (FTIR) and high performance liquid chromatography (HPLC) analyses. The bands at 1600-1800 cm(-1) which indicate the specific region and quality of pectin were detected using FTIR while galacturonic acid content was determined using HPLC. The results showed that the galacturonic acid content of pectin from orange pulp was determined to be 406.44 mg/g powder pectin while that of the modified pectin from the orange pulp was determined to be 465,34 mg/g powder pectin. In addition, flow properties of the pectin samples were determined using rheological analysis. The viscosity and viscoelastic properties of the modified pectin samples were revealed to be different from those of non-modified pectin samples. The consistency index values of unmodified and modified pectin samples were determined to be 0.0559 Pa.s(n) and 0.0046 Pa.s(n), respectively.
AtıfWoS3İncele - MakaleYalnız künye2018THE GENERAL SOLUTION OF A LAYERED MEDIUM RESTING ON A RIGID FOUNDATION
Adiyaman, Gokhan; Öner, Erdal; Birinci, Ahmet
In this study, the general solution of a receding contact problem of layered medium resting on rigid foundation is considered. The layered medium consists of N homogeneous layer with varying material properties and heights. The contact surfaces can be receding or attached. The problem may include M receding contact surfaces. The layered medium is loaded with n concentrated loads transmitted by circular stamps and r distributed loads. The problem is reduced to integral equation system using elasticity theory and Fourier integral transform. The numerical solution of the system is done by using Matlab. A program is written to solve the problem given by the user with any geometry and loading. The program is tested with two studies from the literature and it was shown that the results are compatible.
AtıfWoS3İncele - MakaleAçık Erişim2024Investigation of Some Tree Bark Extracts and Essential Oils for Antioxidant, Antimicrobial and Anti-Quorum Sensing Activities
Yilmaz, Bilge; Tabbouche, Sana; Deniz, Ilhan; Kiliç, Ali Osman; Can, Zehra
Aim of study: The objective of this research is to uncover the bioactive characteristics of ethanol extracts and essential oils from 15 different tree barks (Thuja plicata, Sequoia sempervirens, Eucalyptus globulus, Pinus nigra, Platanus orientalis, Fagus orientalis, Populus tremula, Castanea sativa, Pinus sylvestris, Pinus pinaster, Picea orientalis, Populus nigra, Cryptomeria japonica, Abies nordmanniana, Quercus robur). Material and method: In this study, the bioactive properties of 15 different tree barks were investigated. Ethanol extracts were analyzed for their polyphenolic content, antioxidant activity, and antimicrobial properties. Additionally, the essential oils were evaluated for their anti-quorum sensing capabilities. Main results: Several barks demonstrated high potential as sources of polyphenolic compounds, tannins, and antioxidant activity, indicating their potential as bioactive resources for the forestry and pharmaceutical industries. Research highlights: The ethanol extracts of Eucalyptus globulus, Castanea sativa, and Quercus robur barks showed remarkable results regarding total polyphenolic content, antioxidant activity, and antimicrobial properties. Essential oils from the barks of Populus nigra, Populus tremula, and Platanus orientalis exhibited positive anti-quorum sensing activity. Moreover, both Quercus robur and Eucalyptus globulus displayed high bioactive potential.
AtıfWoS1OpenAlex1İncele - MakaleAçık Erişim2016Scopus SJRQ2Surface, Nanomechanical, and Optical Properties of Mo-Doped GeGaAs Thin Film Deposited by Thermionic Vacuum Arc
Pat, Suat; Senay, Volkan; Özen, Soner; Korkmaz, Sadan
Mo-doped and undoped GeGaAs layers have been deposited by the thermionic vacuum arc (TVA) method, an alternative, fast plasma deposition technique. The thicknesses of the deposited layers were identical. The surface, mechanical, and optical properties of the deposited layers were studied to determine the influence of Mo doping on GeGaAs. The transparency of GeGaAs was shifted towards the near-infrared region by Mo doping. Bandgap values shifted by approximately 0.3 eV. In other words, the bandgap value of Mo-doped GeGaAs was nearly equal to that of GaAs materials. The average roughness and grain size of the Mo-doped material were smaller than for the GeGaAs layer. The particle distributions of the Mo-doped and undoped GeGaAs were almost perfect Gaussians. However, the mean height of the Mo-doped GeGaAs grains was six times that for undoped GeGaAs. The surface was homogeneous. The Mo-doped layer showed greater absorbance than the GeGaAs material. The produced Mo-doped sample showed hybrid properties.
AtıfWoS1OpenAlex1İncele - MakaleAçık Erişim2019Scopus SJRQ1Experimental and Theoretical Investigation of Short- and Long-Heel Cases of Cantilever Retaining Walls in Active State
Kamiloglu, Hakan Alper; Sadoglu, Erol
Failure surfaces are very effective in active lateral earth thrusts acting on cantilever retaining walls. The intersection of failure surface and cantilever retaining wall should be taken into account for determination of active earth thrust. Calculations of lateral earth thrusts vary for two different cases, short heel or long heel, based on the intersection of cantilever wall and failure surface. However, the common methods are devoted to a particular case (long heel or short heel). This study intended to suggest a new lateral earth thrust method that is applicable to cantilever walls with a short heel or long heel using the limit-equilibrium approach. For this purpose, an earth thrust-maximization algorithm was prepared and coded by using Matlab Environment to determine active earth thrust coefficients and failure surface inclination angles occurring behind a cantilever wall in an active case. Also, the failure surfaces occurring behind model cantilever walls and the failure cases were examined experimentally by using particle image velocimetry (PIV) analysis. Consequently, long-heel and short-heel cases and the effective parameters on the cases were investigated analytically and experimentally. (C) 2019 American Society of Civil Engineers.
AtıfWoS23OpenAlex24İncele - MakaleAçık Erişim2025Secondary School Students' Opinions on Teaching the Structure of the Atom with Augmented Reality Application
Gürbüz, Fatih; Sarioglan, Ayberk Bostan
This study is aimed at developing an achievement test on quadrilaterals for seventh-grade students. The concept of the atom can be visualized in different ways in the mind due to its structure, which the naked eye cannot see. Augmented reality (AR) is one of the applications that can be used to teach such concepts. This study aimed to investigate students' views on the use of AR applications in teaching. Phenomenological design, one of the qualitative research designs, was used in the study. The study group consisted of 26 -graders in a public secondary school. AR application was organized to teach the structure of the atom. Within the scope of the study, an interview form consisting of four open-ended questions prepared by the researchers and submitted to expert opinion for content validity was used as a data collection tool. When the students' answers to the questions were examined, it was determined that they had positive opinions that AR application could be used in other courses and different subjects, that this application was more instructive because it concretized the subject, that it caused a better understanding of the subject it was used in, and that it increased participation in the lesson due to the possibilities of providing three-dimensional images. Suggestions were made based on the results.
- MakaleAçık Erişim2026Scopus SJRQ4MORTUARY CULT AND KÖR CEMETERY IN TURKISH CULTURE
Kabak, Turgay; Abali, Ismail
In Turkiye, the Yoruks, who have a nomadic lifestyle, migrate to a different region every season as part of their animal husbandry activities and bury their deceased relatives randomly anywhere during their migrations. This study focuses on the rare and interesting burial traditions of the Yoruks, as well as these cemeteries, which are called blind. In the article, the locations of these cemeteries were determined by field research method, the oral culture of the local people concerning these cemeteries was recorded and examined in the light of the mortuary cult that the Turks brought from the pre-Islamic period. With this examination, it has been observed that the Turks believe that the souls of dead people do not disappear and that the soul's connection with this world is not interrupted, and that they created an ancestor cult around this belief.
- MakaleAçık Erişim2017The Possibilities of Using Some Spice Essential Oils in Ice Cream Production
Macit, Emine; Çaglar, Abdullah; Bakirci, Ihsan
In present study, some physical, chemical, sensory and microbiological characteristics of ice cream samples produced by using 4 different essential oils (Coconut, lemon bark, clove and cinnamon) in 2 different levels (0.2% and 0.4%) were investigated. The findings indicated that although the addition of essential oil was not significantly effective on the physical and chemical properties of ice cream samples (P>0.05), the melting rates increased during storage. The sample with 0.2% coconut essential oil was the most favorite sample in sensory evaluations, while the sample with 0.4% clove essential oil was the least favorite sample. In general, samples with 0.2% essential oil were more appreciated than samples with 0.4%. It has been determined that ice cream samples conformed to TS 4265 Ice Cream Standard (Turkish Standard) in terms of microbiological properties. With this study, it was determined that some essential oils can be used as a natural aroma substance in the production of ice cream.
AtıfWoS6OpenAlex5TR Dizin3İncele - MakaleAçık Erişim2019Effects of Some Stabilizers on the Textural Properties of Set-Type Yogurt
Macit, Emine; Karaoglu, M. Murat; Bakirci, Ihsan
This study was conducted to investigate the effect of various stabilizers on textural properties of set yogurt. Yogurt samples were prepared by using seven various stabilizers such as sodium caseinate, gelatin, carrageenan, xanthan gum, guar gum, locust bean gum and native corn starch. Control group samples were produced without using stabilizer. Textural analyzes were made with a TA-XT2i texture analyzer. As a result of the statistical analysis, it was determined that stabilizer and storage time had a significant effect (p<0.01) on all texture parameters of yogurt samples, the relaxation force values were not affected by only storage period (p>0.05). In conclusion, Nacaseinate was the most suitable stabilizer for yogurt texture compared to all stabilizers. These findings may contribute to the selection of stabilizer material or preparation of stabilizer mixtures that can be used in the production of set type yogurt for developing different textural parameters.
AtıfWoS11OpenAlex6İncele - MakaleYalnız künye2024THE PLACE AND IMPORTANCE OF FOLK DANCES IN TURKISH FOLKLORE
Yildirim, Oguz; Inalkac, Oktay; Yildirim, Yavuz; Kiratli, Tuncay; Kara, Ahmet
The subject of the research was determined as the place and importance of folk dances in Turkish folklore. The aim of the research is to reveal the place and importance of folk dances and music, which are among the phenomena in Turkish folklore, in Turkish folklore. The method of the research is a descriptive study and the current situation was tried to be revealed by examining the scientific sources obtained through the scanning method. The importance of the research is considered important in terms of revealing the place and importance of folk dances and music, which are an important element of Turkish culture and civilization, in folklore. Folklore and culture are related to each other due to their similar nature. It constitutes traditional products (customs, traditions, language, religion, oral and written and architectural art, sports, literature, etc.) belonging to the national and spiritual elements of a society with a cultural history in a certain period. Folklore, on the other hand, is a science that researches, examines and compiles the cultural products produced in the past by delving into unknown historical depths to which society and which period they belong. Folk dances are also a culture-art phenomenon within folklore. Folk dances, which are among the Turkish folkloric elements, carry the cultural phenomena that the Turkish nation has revealed throughout its five thousand years of life, from its emergence on the stage of history to the present day. Turks have existed in many different geographies in the world and as a result, Turkish folklore has revealed the products of a very rich cultural accumulation. Among these products, folk dances have an important place. Folk dances are distributed in different types according to regions in Turkey. This distribution has brought great diversity to folk dances and contributed to Turkish folklore. As a result, folk dances, as an intangible cultural heritage, contribute to Turkish folklore by showing their presence in Turkey's geography with different types and diversity qualities, especially the rich accumulation that the Turks have acquired from the time period when they appeared on the stage of history until today. In this direction, the research tried to reveal the place and importance of folk dances in Turkish folklore, taking into account the contributions of our folk dances in Turkish folklore.
AtıfWoS1İncele
