Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Çullu, Mustafa(2)
- Akpinar, Muhammet Vefa(1)
- Aksut, Yavuz Selim(1)
- Altunoiv, Mustafa(1)
- Atar, Musa(1)
- Bal, Arzu(1)
- Dedeturk, Mutlu(1)
- Demírel, Ugur(1)
- Külekçi, Gokhan(1)
- Küçükosman, Ridvan(1)
- Seferoglu, Aysegul Gunes(1)
- Seferoglu, Mehmet Tevfik(1)
- Süküroglu, Ebru Emine(1)
- Süküroglu, Suleyman(1)
- Terhan, Meryem(1)
- Totik, Yapr(1)
- Yalcin, Numan(1)
- Yasar, Mehmet(1)
- Yasar, Sekip Sadiye(1)
- Yetgín, Sukru(1)
- Çam, Handan(1)
- Çelik, Muhammet(1)
Yayınlar
- MakaleAçık Erişim2026Formulation of mechanical properties of hybrid fiber alkali-activated concretes by data analysis
Aksut, Yavuz Selim; Yetgín, Sukru
In this study, ground blast furnace slag (GBFS) and waste volcanic rock dust (RD) produced in a natural stone processing plant were used as binders. The binders were activated with Sodium Hydroxide (NaOH) and Sodium Silicate (Na2SiO3) to produce two types of concrete: alkali-activated concrete without fibers (AAC) and alkali-activated concrete with fibers (FAAC). In the production of concrete, steel and polyester fibers were used separately and hybrid at 0.25%, 0.50%, 0.75% and 1.0% by volume and a total of 117 15x15x15 cm cube specimens were produced. The mechanical properties of the specimens were evaluated by concrete surface hardness, ultrasonic pulse velocity and concrete compressive strength tests at 3, 7 and 28 days. The results obtained using non-destructive test methods were matched with concrete compressive strength values using various empirical formulas. Calculated concrete compressive strength values and actual concrete compressive strength values were compared using data analysis method. As a result, it was observed that there was a very significant correlation between the experimental compressive strength and the combined method in which 7-day surface hardness and ultrasound transmission rate were used together to calculate the compressive strength.
- MakaleAçık Erişim2025Investigation of Fluctuations in Cryptocurrency Transactions with Sentiment Analysis
Demírel, Ugur; Çam, Handan
This study investigates public sentiment about popular cryptocurrencies listed on crypto exchanges in Turkey, using comments shared on social media platforms and online forums. The research seeks to enhance the existing body of knowledge by overcoming the shortcomings of sentiment analysis studies focused on Turkish texts. Data collected from social media and online forums were examined with sentiment analysis techniques. A total of 607,592 comments were analyzed, of which 89,986 were classified as negative, 72,655 as positive, and 444,951 as neutral. For binary classification, 89,986 negative and 72,655 positive examples were selected and machine-learning models were trained and tested on 162,641 examples. The study's methodology includes an in-depth examination of sentiment analysis results obtained using machine learning classifiers. The findings show how various cryptocurrencies are perceived on different social media platforms. For instance, BTC (Bitcoin) is generally perceived negatively on Investing.com and Telegram, while ETH (Ethereum) generally displays more negative views. These results help investors understand their perceptions and market expectations towards cryptocurrencies. This study deepens the role of social media sentiment analysis in cryptocurrency markets, contributing to the development of new methods and approaches for future research.
- BildiriAçık Erişim2023Solutions of Multiplicative Integral Equations via The Multiplicative Power Series Method
Bal, Arzu; Yalcin, Numan; Dedeturk, Mutlu
In this study, definitions of types of multiplicative integral equations are given. And solutions of different types of multiplicative integral equations are investigated using the multiplicative power series method. These are supported by numerical examples.
- MakaleAçık Erişim2021The investigation of mechanical properties of polypropylene fiber-reinforced composites produced with the use of alternative wastes
Külekçi, Gokhan; Çullu, Mustafa
Various studies on the disposal or storage of the wastes generated due to mining activities have been carried out until today. With the developing technology, the use of alternative products instead of aggregates in Composite and the effect of fiber addition were investigated. The most common of these studies is the bending strength tests on the beam sample. In this study, solid wastes generated by mining operations were used instead of aggregate used in Composite. Beam samples were poured with the dimensions of 40x40x160 mm by adding 4-6 kg/m(3) polypropylene fiber to the mixture obtained by using these solid wastes; then, its effects on ultrasonic pulse velocity test, tensile test, and compressive strength tests were conducted. According to the results of these tests, it was found that the fibers had a positive effect on compressive strength and bending strength. Also, it was found that water absorption rates and densities did not have an effect, while the ultrasonic pulse velocity decreased with increasing fiber content.
- MakaleYalnız künye2021Investigation of Effect of Dew Point Temperatures on Design of Condensing Heat Recovery Units According to Fuel Types
Terhan, Meryem
In this study, dew point temperatures of water and sulphuric acid vapour in flue gas are predicted as theoretical for fuels types such as coal, fuel oil, natural gas, LPG, wood with the different cities in Turkey. The factors like the excess air coefficient, relative humidity rate and the altitude of the city affected by the dew point temperatures and the mole ratios of water and sulphuric acid vapour in flue gas are studied. According to the results of the study, while the water dew point temperature changes for coal, wood, fuel oil, natural gas and LPG, over the range 30-40 degrees C, 40-50 degrees C, 37-50 degrees C, 44-60 degrees C and 41-56 degrees C, respectively; the acid dew point temperature waves to 125 degrees C from 140 degrees C for coal types and to 131 degrees C from 145 degrees C for fuel oil types in Turkey. To predict the condensing zone, a condensing economizer for a natural gas-fired boiler in a heating system is designed with Finite difference method. According to the results of the design, while the first 100 m of the heat exchanger tube is non-condensing zone, the only 10 m is the condensing zone.
- BildiriAçık Erişim2021Investigation of In-Vitro Properties of NiTi Alloy After Micro Arc Oxidation
Süküroglu, Suleyman; Totik, Yapr; Süküroglu, Ebru Emine; Küçükosman, Ridvan
As material science is integrated into medical science as in other fields, the variety, development and usage areas of biomaterials increase. One of the biomaterials in this variety is NiTi alloys. This study was focused on the coating of TiO2 layer by using the method of Micro Ark Oxidation with the aim of the improvement of surface and mechanical properties of Shapedmemory and bio material NiTi alloy. Structural properties of the coatings were analysed by of SEM and XRD. In vitro ability was investigated by soaking the coated NiTi samples in simulated body fluid (SBF) at temperature 37 degrees C for various time periods. After soaking, Ni+2 release was applied to the media where coated and uncoated shape-memory NiTi samples are available, and its control was made by means of ICP-MS device. The results also show that Toxic and carcinogenic effects of Ni+2 release is significantly reduced by the TiO2 coating. Thus, it is observed that the properties that limit the use of NiTi alloys has been substantially fixed by MAO coating. It was found that the bioactive properties of the TiO2 coated NiTi substrate increased by MAO method and at the end of the 72 hour, there was no statistically any cytotoxicity in cell viability compared to the NiTi substrate.
- MakaleYalnız künye2020Economic Analysis of the Use of Reclaimed Asphalt Pavement (RAP) Materials in Plant-Mix Base Courses
Seferoglu, Aysegul Gunes; Seferoglu, Mehmet Tevfik; Akpinar, Muhammet Vefa; Çelik, Muhammet
The aim of this study is to determine the financial benefits to be gained based on the percentages of reclaimed asphalt pavement (RAP) material suitable for use in plent-mix courses (PBCs) to be designed according to the specification of Turkey Department of Transportation. Cost analysis of all RAP mixtures were made considering the construction of the plant-mix base course and the transportation costs of the materials, it was researched that the use of RAP would be an economical application in terms of how far the RAP material was taken. As a result of the study, it has been determined that the use of 100% RAP material in PBC is possible with cement reinforcement and it provides a profit of more than 16% in terms of costs in case of using virgin aggregate (VA) instead. RAP material is an alternative to virgin aggregate and is a more economical material in terms of cost.
- MakaleAçık Erişim2019Some Physical and Mechanical Properties of Impregnated Chestnut Wood with Natural and Chemical Agent Exposed to Outdoor Conditions
Yasar, Mehmet; Altunoiv, Mustafa
Wood preservatives have been widely used to extend the service life of wood. The most objectionable environment for wood is outdoor conditions. In this study, test specimens prepared from chestnut wood (Castanea sativa Mill) were impregnated with natural and chemical impregnation agent. It was aimed to determine the effect of outdoor conditions on physical and mechanical properties of wood material by keeping them under these conditions for one year. As natural impregnation material pine tannin and acorn tannins, as chemical impregnation material imersol aqua and timbercare aqua were used. The retention amount, air-dried density, bending strength, modulus of elasticity, compression strength parallel to fibers, adhesion strength parallel to fibers, screw withdrawal strength were determined. As a result, it can be said that the physical and mechanical test values can compare wood impregnated with natural impregnation materials to wood impregnated with chemical impregnation materials after one year exposed to outdoor conditions.
- MakaleAçık Erişim2018The Effects of Wood Preservatives on the Combustion Characteristics of Sessile Oak (Quercus Petreae L.)
Yasar, Sekip Sadiye; Atar, Musa
This study carried out to determine the combustion properties of the sessile oak wood (Quercus petraea L.) which impregnated with wood preservative and subjected to surface treatments. For this purpose, the samples, which were prepared from sessile oak wood according to ASTM-E 160-50 combustion principles, impregnated with wolmanit-CB (WC) and tanalith-E (T) in accordance with ASTM-D 1413-76 and then synthetic (St) and Water-based (wb) varnishes were applied according to ASTM-D 3023. The combustion test was carried out in 3 stages, combustion with flame (CWF), self-combustion without flame source (CWOF) and ember combustion stage (ECP). It was aimed to determine the combustion temperature values in CWF, CWOF and ECP stage, weight loss, total combustion time and demolition time. As a result, impregnation applications have increased the total combustion time to between 15-18% and reduced the demolition period. The exact opposite results were obtained for the varnish types, the total combustion time was reduced by 19-21% and the demolition time increased by 10-22%. In CWF stage, the highest temperature was obtained in water-based varnished samples (490 degrees C), the lowest in non-varnished samples (458 degrees C); in CWOF stage the highest temperature in water-based varnished samples (572 degrees C), the lowest in synthetic varnished samples (544 degrees C); and in ECP stage the highest temperature in non-varnished samples (306.5 degrees C), the lowest in the samples with the synthetic varnished (262.7 degrees C).
- MakaleAçık Erişim2018Investigation Of Mechanical And Physical Properties of Concrete Produced to Lead-Zinc Mining Waste Rocks
Çullu, Mustafa
The purpose of this study is to investigate the physical and mechanical properties of concrete produced from lead-zinc mine waste (tallow) products. In this context, the physical chemical, mineralogical and petrography characteristics of rocks obtained from zinc-lead mine were analyzed first. Concrete strength classes of C16/20, C25/30 and C35/45 5 replaced with 25%, 50% and 75% rates of limestone were prepared with lead mine waste. The physical and mechanical properties of the prepared concrete samples were determined. As a result, when lead-zinc mine waste is used as concrete aggregate, while the porosity and the water absorption of prepared samples were decreased, the physical density were increased as compared to limestone. As the result of the positive effect of physical properties, compressive and tensile strength were increased.
- DergiJOURNAL OF POLYTECHNIC-POLITEKNIK DERGISI