05. Fakülteler

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Citation - WoS: 11
Citation - Scopus: 15
Accuracy Assessment of Dems Derived From Multiple Sar Data Using the Insar Technique
(SPRINGER HEIDELBERG, 2021) Karabörk, Hakan; Makineci, Hasan Bilgehan; Orhan, Osman; Karakuş, Pınar
In this study, digital elevation models (DEMs) derived from AlosPalsar data (Japanese Space Agency-JAXA), Sentinel-1A data, and Envisat ASAR data (European Space Agency-ESA) were compared by using a global navigation satellite system (GNSS). In addition, AW3D30, SRTM, and ASTER GDEM (open-access DEMs) data were also included in the accuracy evaluation. The DEM accuracies were investigated in three different terrain types, namely a plain area, mountainous area and agricultural area, and compared at elevation values on a pixel-based. The accuracy obtained from the ALOS PALSAR satellite data was found to be more reliable for all three terrain types. The standard deviation and root mean square values were calculated and compared to each other. The results of the accuracy assessments showed that the best result for the plain area was obtained with the Sentinel-1A and SRTM data, for the mountainous area was obtained with the SRTM data and for agricultural area was obtained with the ALOS PALSAR and SRTM data.
Citation - WoS: 24
Citation - Scopus: 40
An Adaptive Method for Traffic Signal Control Based on Fuzzy Logic With Webster and Modified Webster Formula Using Sumo Traffic Simulator
(IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2021) Ali, Muzamil Eltejani Mohammed; Durdu, Akif; Çeltek, Seyit Alperen; Yılmaz, Alper
In the past, the Webster optimal cycle time formula was limited to calculate the optimal cycle from historical data for fixed-time traffic signal control. This paper focuses on the design of an adaptive traffic signal control based on fuzzy logic with Webster and modified Webster's formula. These formulas are used to calculate the optimal cycle time depending on the current traffic situation which applying in the next cycle. The alternation of the traffic condition between two successive cycles is monitored and handled through the fuzzy logic system to compensate the fluctuation. The obtained optimal cycle time is used to determine adaptively the effective phase green times i.e. is used to determine adaptively the maximum allowable extension limit of the green phase in the next cycle. The SUMO traffic simulator is used to compare the results of the proposed adaptive control methods with fuzzy logic-based traffic control, and fixed-time Webster and modified Webster-based traffic control methods. The proposed methods are tested on an isolated intersection. In this study, real field-collected data obtained from three, four, and five approaches intersections in Kilis/Turkey are used to test the performance of the proposed methods. In addition, to examine the efficiency of the proposed techniques at heavy demands, the arbitrary demands are generated by SUMO for a four approaches intersection. The obtained simulation results indicate that the proposed methods overperform the fixed time and fuzzy logic-based traffic control methods in terms of average vehicular delay, speed, and travel time.
Citation - WoS: 9
Citation - Scopus: 11
Adrenal Tumor Segmentation Method for Mr Images
(ELSEVIER IRELAND LTD, 2018) Barstuğan, Mücahid; Ceylan, Rahime; Asoğlu, Semih; Cebeci, Hakan; Koplay, Mustafa
Background and objective: Adrenal tumors, which occur on adrenal glands, are incidentally determined. The liver, spleen, spinal cord, and kidney surround the adrenal glands. Therefore, tumors on the adrenal glands can be adherent to other organs. This is a problem in adrenal tumor segmentation. In addition, low contrast, non-standardized shape and size, homogeneity, and heterogeneity of the tumors are considered as problems in segmentation. Methods: This study proposes a computer-aided diagnosis (CAD) system to segment adrenal tumors by eliminating the above problems. The proposed hybrid method incorporates many image processing methods, which include active contour, adaptive thresholding, contrast limited adaptive histogram equalization (CLAHE), image erosion, and region growing. Results: The performance of the proposed method was assessed on 113 Magnetic Resonance (MR) images using seven metrics: sensitivity, specificity, accuracy, precision, Dice Coefficient, Jaccard Rate, and structural similarity index (SSIM). The proposed method eliminates some of the discussed problems with success rates of 74.84%, 99.99%, 99.84%, 93.49%, 82.09%, 71.24%, 99.48% for the metrics, respectively. Conclusions: This study presents a new method for adrenal tumor segmentation, and avoids some of the problems preventing accurate segmentation, especially for cyst-based tumors. (C) 2018 Elsevier B.V. All rights reserved.
Citation - WoS: 42
Citation - Scopus: 49
Adsorption of Malachite Green and Methyl Violet 2b by Halloysite Nanotube: Batch Adsorption Experiments and Box-Behnken Experimental Design
(Elsevier Ltd, 2022) Altun, Türkan; Ecevit, Hüseyin
Dyes constitute a significant part of the pollutants in industrial wastewater. In this study, halloysite nanotube (HNT) was used for adsorption of malachite green and methyl violet 2B dyes from the solution. Using batch adsorption experiments and response surface method, parameters affecting adsorption have been optimized. As a consequence of the batch experiments, after 60 min, the adsorption equilibrium state was achieved at 3 g L?1 HNT dosage, 125 mg L?1 dye concentration and natural solution pH. Temperature did not significantly affect the adsorption. The adsorption equilibrium data can be said to have fitted the Langmuir, Freundlich, Dubinin-Radushkevich and Temkin isotherms well for the both dyes. The Langmuir maximum monolayer malachite green and methyl violet 2B adsorption capacities (As) of HNT are 74.95 mg g?1 and 67.87 mg g?1, respectively. Adsorption processes are more consistent with the pseudo-second-order kinetic model. In addition, both intra-particle diffusion and film diffusion are effective as rate-determining steps in adsorption. Thermodynamic calculations showed that the adsorption is exothermic and spontaneous. The regeneration of HNT after adsorption was confirmed in five cycles. By using the Box-Behnken response surface method, the parameters affecting the adsorption process were modeled, the effects of these parameters on the adsorption efficiency were expressed mathematically and the optimum operating parameters were determined. © 2022
Citation - WoS: 50
Citation - Scopus: 55
Advanced Oxidation of Landfill Leachate: Removal of Micropollutants and Identification of By-Products
(ELSEVIER, 2021) Ateş, Havva; Argun, Mehmet Emin
Landfill leachate contains several macropollutants and micropollutants that cannot be removed efficiently by conventional treatment processes. Therefore, an advanced oxidation process is a promising step in post or pre-treatment of leachate. In this study, the effects of Fenton and ozone oxidation on the removal of 16 emerging micropollutants including polycyclic aromatic hydrocarbons (PAHs), phthalates, alkylphenols and pesticides were investigated. The Fenton and ozone oxidation of the leachate were performed with four (reaction time: 20-90 min, Fe(II) dose: 0.51-2.55 g/L, H2O2 dose: 5.1-25.5 g/L and pH: 3-5) and two (ozonation time: 10-130 min and pH: 4-10) independent variables, respectively. Among these operating conditions, reaction time played more significant role (p-value < 0.05) in eliminating di-(2-Ethylhexyl) phthalate, 4-nonylphenol and 4-tert-octylphenol for both processes. The results showed that Fenton and ozone oxidation processes had a high degradation potential for micropollutants except for the PAHs including four and more rings. Removal efficiencies of micropollutants by ozone and Fenton oxidation were determined in the range of 5-100%. Although the removal efficiencies of chemical oxygen demand (COD) and some micropollutants such as phthalates were found much higher in the Fenton process than ozonation, the degradation products occurred during the Fenton oxidation were a higher molecular weight. Moreover, the oxidation intermediates for the both processes were found as mainly benzaldehyde, pentanoic acid and hydro cinnamic acid as well as derivatives of naphthalenone and naphthalenediol. Also, acid ester with higher molecular weight, naphthalene-based and phenolic compounds were detected in the Fenton oxidation.
Citation - WoS: 8
Citation - Scopus: 12
The Aerodynamic Effects of Blade Pitch Angle on Small Horizontal Axis Wind Turbines
(Emerald Group Publishing Ltd, 2022) Kaya, Mehmet Numan; Uzol, Oguz; Ingham, Derek; Köse, Faruk; Büyükzeren, Rıza
Purpose The purpose of this paper is to thoroughly investigate the aerodynamic effects of blade pitch angle on small scaled horizontal axis wind turbines (HAWTs) using computational fluid dynamics (CFD) method to find out the sophisticated effects on the flow phenomena and power performance. Design/methodology/approach A small HAWT is used as a reference to validate the model and examine the aerodynamic effects. The blade pitch angle was varied between +2 and -6 degrees, angles which are critical for the reference wind turbine in terms of performance, and the CFD simulations were performed at different tip speed ratio values, lambda = 2, 3, 4, 5, 6, 7, 9 and 10.5 to cover the effects in various conditions. Results are examined in two different aspects, namely, general performance and the flow physics. Findings The power performance varies significantly according to the tip speed ratio; the power coefficient increases up to a certain pitch angle at the design tip speed ratio (lambda = 6); however, between lambda = 2 and 4, the more the blade is pitched downwards, the larger is the power coefficient, the smaller is the thrust coefficient. Similarly, for tip speed ratios higher than lambda = 8, the positive effect of the low pitch angles on the power coefficient at lambda = 6 reverses. The flow separation location moves close to the leading edge at low tip speed ratios when the blade is pitched upwards and the also tip vortices become more intense. In conclusion, the pitch control can significantly contribute to the performance of small HAWTs depending on different conditions. Originality/value In the literature, only very little attention has been paid to the aerodynamic effects of pitch angle on HAWTs, and no such study is available about the effects on small HAWTs. The change of blade pitch angle was maintained at only one degree each time to capture even the smallest aerodynamic effects, and the results are presented in terms of the power performance and flow physics.
Citation - WoS: 25
Citation - Scopus: 29
Aerogels as Promising Materials for Antibacterial Applications: a Mini-Review
(ROYAL SOC CHEMISTRY, 2021) Kaya Güzel, Gülcihan; Aznar, Elena; Deveci, Hüseyin; Martinez-Manez, Ramon
The increasing cases of bacterial infections originating from resistant bacteria are a serious problem globally and many approaches have been developed for different purposes to treat bacterial infections. Aerogels are a novel class of smart porous materials composed of three-dimensional networks. Recently, aerogels with the advantages of ultra-low density, high porosity, tunable particle and pore sizes, and biocompatibility have been regarded as promising carriers for the design of delivery systems. Recently, aerogels have also been provided with antibacterial activity through loading of antibacterial agents, incorporation of metal/metal oxides and via surface functionalization and coating with various functional groups. In this mini-review, the synthesis of aerogels from both conventional and low-cost precursors is reported and examples of aerogels displaying antibacterial properties are summarized. As a result, it is clear that the encouraging antibacterial performance of aerogels promotes their use in many antibacterial applications, especially in the food industry, pharmaceutics and medicine.
Citation - WoS: 29
Citation - Scopus: 54
Alexnet Architecture Variations With Transfer Learning for Classification of Wound Images
(Elsevier B.V., 2023) Eldem, H.; Ülker, E.; Işıklı, O.Y.
In medical world, wound care and follow-up is one of the issues that are gaining importance to work on day by day. Accurate and early recognition of wounds can reduce treatment costs. In the field of computer vision, deep learning architectures have received great attention recently. The achievements of existing pre-trained architectures for describing (classifying) data belonging to many image sets in the real world are primarily addressed. However, to increase the success of these architectures in a certain area, some improvements and enhancements can be made on the architecture. In this paper, the classification of pressure and diabetic wound images was performed with high accuracy. The six different new AlexNet architecture variations (3Conv_Softmax, 3Conv_SVM, 4Conv_Softmax, 4Conv_SVM, 6Conv_Softmax, 6Conv_SVM) were created with a different number of implementations of Convolution, Pooling, and Rectified Linear Activation (ReLU) layers. Classification performances of the proposed models are investigated by using Softmax classifier and SVM classifier separately. A new original Wound Image Database are created for performance measures. According to the experimental results obtained for the Database, the model with 6 Convolution layers (6Conv_SVM) was the most successful method among the proposed methods with 98.85% accuracy, 98.86% sensitivity, and 99.42% specificity. The 6Conv_SVM model was also tested on diabetic and pressure wound images in the public medetec dataset, and 95.33% accuracy, 95.33% sensitivity, and 97.66% specificity values were obtained. The proposed method provides high performance compared to the pre-trained AlexNet architecture and other state-of-the-art models in the literature. The results showed that the proposed 6Conv_SVM architecture can be used by the relevant departments in the medical world with good performance in medical tasks such as examining and classifying wound images and following up the wound process. © 2023 Karabuk University
Citation - WoS: 14
Citation - Scopus: 14
All-Dry Synthesis of Poly(2-Ethylhexyl Acrylate) Nanocoatings Using Initiated Chemical Vapor Deposition Method
(ELSEVIER SCIENCE SA, 2019) Şakalak, Hüseyin; Karaman, Mustafa
In this study, Poly(2-ethylhexyl acrylate) (PEHA) thin films were deposited on different substrates by initiated chemical vapor deposition (iCVD) technique. Being a long alkyl chain acrylate with a suitably low glass transition temperature, PEHA is an important member of acrylates family, which is used extensively in adhesives, paints, and coating applications. In iCVD, use of the tert-butyl peroxide as an initiator allowed a deposition rate of 155 nm/min at a filament temperature of 280 degrees C. Precursor flow ratios, filament and substrate temperatures were found to be important parameters that effect the deposition rates. The negative relation between substrate temperature and deposition rates implied an adsorption limited kinetics. FTIR and XPS analyses of the deposited films confirmed that the chemical functionality of the EHA monomer preserved well after iCVD. It was also revealed that the as-deposited films are smooth, uniform and optically transparent. PEHA film deposited by iCVD on glass improved the optical transmittance of glass, by acting as an anti-reflection coating due to its suitable refractive index of 1.45.
Citation - WoS: 17
Citation - Scopus: 19
Analysis of Electrospinning and Additive Effect on ? Phase Content of Electrospun Pvdf Nanofiber Mats for Piezoelectric Energy Harvester Nanogenerators
(Institute of Physics, 2022) Oflaz, Kamil; Özaytekin, İlkay
Harvesting energy with piezoelectric nanoparticles enables the development of self-powered devices. Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF) has been widely used in a variety of fields due to its superior piezoelectric properties. PVDF’s piezoelectric performance is affected by the presence of polar phase in the crystalline structure. The electrospinning process was used in this study to achieve high ? phase ratios in the PVDF crystalline structure using various additives (graphene, boron nitride, and quartz (SiO2)). The Taguchi experimental design method was used to determine the most significant parameters affecting ? phase content from seven factors, as well as the optimal levels of the significant factors. The Fourier transform infrared, x-ray diffraction, scanning electron microscopy, energy-dispersive x-ray and differential scanning calorimetry analyses were used to characterize the composite PVDF nanofiber mats produced under optimal conditions, and the output voltage was measured using an oscilloscope. The composite PVDF nanofiber mat with the highest ? phase concentration demonstrated a maximum output voltage of 8.68 V under optimal conditions, indicating that it outperformed than pure PVDF under equal electrospinning conditions. © 2022 IOP Publishing Ltd.
Citation - WoS: 37
Citation - Scopus: 46
Analysis of the Cp Structure of the Yukawa Coupling Between the Higgs Boson and Tau Leptons in Proton-Proton Collisions at Root S=13 Tev
(Springer, 2022) Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Bergauer, T.; Chatterjee, S.; Dragicevic, M.; Güler, Yalçın; The CMS Collaboration
The first measurement of the CP structure of the Yukawa coupling between the Higgs boson and tau leptons is presented. The measurement is based on data collected in proton-proton collisions at root s = 13 TeV by the CMS detector at the LHC, corresponding to an integrated luminosity of 137 fb(-1). The analysis uses the angular correlation between the decay planes of tau leptons produced in Higgs boson decays. The effective mixing angle between CP-even and CP-odd tau Yukawa couplings is found to be -1 +/- 19 degrees, compared to an expected value of 0 +/- 21 degrees at the 68.3% confidence level. The data disfavour the pure CP-odd scenario at 3.0 standard deviations. The results are compatible with predictions for the standard model Higgs boson.
Citation - WoS: 8
Citation - Scopus: 8
Ancient Isaura Quarries in and Around Zengibar Castle (bozkir, Konya), Central Anatolia, Turkey
(SPRINGER HEIDELBERG, 2020) Gökçe, Mehmedi Vehbi; İnce, İsmail; Okuyucu, Cengiz; Doğanay, Osman; Fener, Mustafa
Zengibar Castle was built by the Isaurian during antique ages on the summit of Mount Asar, approximately 20 km west of the town of Bozkir, Konya, Turkey. The aims of this study are to determine the lithological, petrographic, and mechanical characteristics of the building stones that were used to construct the walls and buildings in Zengibar Castle in order to determine the quarrying techniques of these stones and to determine which structures they were used in. A number of antique quarries of various sizes were located in Isaura, four of which produced a significantly higher volume of building stones. These antique quarries were mostly located on hillsides in carbonate rock of the Late Triassic Dutdere formation located in the Bolkardagi Units and were run phase by phase. The porosity range of the rocks was found to be between 0.85 and 0.90% and the dry density and uniaxial compressive strength were found to range from 2.67 to 2.68 g/cm(3)and 83.10 to 96.60 MPa, respectively. The results of this study suggest that the stones that were quarried in these quarries were used as the main building material or flooring material in various constructions in Zengibar Castle, including religious buildings such as temples and chapels, social buildings such as dwellings, theaters, baths, fountains, and cemeteries, defense and security structures such as watchtowers, fortification walls, and city gates, in monumental tombs, and in stones in which reliefs and inscriptions were carved.
Citation - WoS: 8
Citation - Scopus: 7
Ann Estimation Model for Photogrammetry-Based Uav Flight Planning Optimisation
(TAYLOR & FRANCIS LTD, 2022) Makineci, Hasan Bilgehan; Karabörk, H.; Durdu, A.
Artificial intelligence (AI) is undergoing a ground-breaking period. Recently, AI affects almost every part of human life. Using AI in path planning for Unmanned Aerial Vehicle (UAV) attracts attention as a novel need. The inputs that form the base of UAV use in photogrammetry are UAV Type (UT), Ground Sampling Distance (GSD), Overlap Rates (OR), and Atmospheric Conditions (AC). Input parameters directly impact the UAV's Flight Time (FT) and Battery Status (BS). Weighting and optimizing these parameters are the main ideas of this study. The effects of input values (GSD, OR, UT, AC) on the outputs (BS and FT) were optimized using Artificial Neural Networks (ANN) in this study. For the analysis, results have been produced in which different training algorithms are preferred (Gradient Descent - GD - and Levenberg-Marquardt - LM). The GD algorithm has reached 77.65% accuracy in FT estimation and 80.91% estimation accuracy on normalized data on the BS. Then, the correlation between the produced model and the input parameters and the output parameters was determined, and the weights of the inputs were revealed. As a result, it was determined that the AC parameter has the most significant effect on BS and FT. Also, it has been identified that the normalization process has a considerable impact on optimization.
Citation - WoS: 18
Citation - Scopus: 19
Antibacterial Activity of Linezolid Against Gram-Negative Bacteria: Utilization of Epsilon-Poly Capped Silica Xerogel as an Activating Carrier
(MDPI, 2020) Kaya Güzel, Gülcihan; Medaglia, Serena; Candela-Noguera, Vicente; Tormo-Mas, Maria Angeles; Marcos, Maria Dolores; Aznar, Elena; Martinez-Manez, Ramon
In recent times, many approaches have been developed against drug resistant Gram-negative bacteria. However, low-cost high effective materials which could broaden the spectrum of antibiotics are still needed. In this study, enhancement of linezolid spectrum, normally active against Gram-positive bacteria, was aimed for Gram-negative bacteria growth inhibition. For this purpose, a silica xerogel prepared from a low-cost precursor is used as a drug carrier owing to the advantages of its mesoporous structure, suitable pore and particle size and ultralow density. The silica xerogel is loaded with linezolid and capped with epsilon-poly-l-lysine. The developed nano-formulation shows a marked antibacterial activity against to Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. In comparison to free linezolid and epsilon-poly-l-lysine, the material demonstrates a synergistic effect on killing for the three tested bacteria. The results show that silica xerogels can be used as a potential drug carrier and activity enhancer. This strategy could provide the improvement of antibacterial activity spectrum of antibacterial agents like linezolid and could represent a powerful alternative to overcome antibiotic resistance in a near future.
Citation - WoS: 42
Citation - Scopus: 46
Apricot Kernel Shell Waste Treated With Phosphoric Acid Used as a Green, Metal-Free Catalyst for Hydrogen Generation From Hydrolysis of Sodium Borohydride
(PERGAMON-ELSEVIER SCIENCE LTD, 2020) Fangaj, Enis; Ceyhan, Ayhan Abdullah
In this study, grinded apricot kernel shell (GAKS) biobased waste was used for the first time as a cost-effective, efficient, green and metal-free catalyst for hydrogen generation from the hydrolysis reaction of sodium borohydride (NaBH4). For the hydrogen production by NaBH4 hydrolysis reaction, GAKS was treated with various acids (HCl, HNO3, CH3COOH, H3PO4), salt (ZnCl2) and base (KOH). As a result, the phosphoric acid (H3PO4) demonstrated better catalytic activity than other chemical agents. The hydrolysis of NaBH4 with the GAKS-catalyst (GAKS(cat)) was studied depending on different parameters such as acid concentration, furnace burning temperature and time, catalyst amount, NaBH4 concentration and hydrolysis reaction temperature. The obtained GAKS(cat) was characterized by ICP-MS, elemental analysis, TGA, XRD, FT-IR, Boehm, TEM and SEM analyses and was evaluated for its catalytic activity in the hydrogen production from the hydrolysis reaction of NaBH4. According to the results, the optimal H3PO4 percentage was found as 15%. The maximum hydrogen generation rate from the hydrolysis of NaBH4 with the GAKS(cat) was calculated as 20,199 mL min(-1) g(cat)(-1) As a result, it can be said that GAKS treated with 15% H3PO4 as a catalyst for hydrogen production is an effective alternative due to its high hydrogen production rate. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
Citation - WoS: 72
Citation - Scopus: 78
Article Info Keywords: Cfrp Reinforced Concrete T-Beams Strengthening Analytical Analysis Anchorage Building Codes Damage Analysis
(Elsevier Science Inc, 2022) Yazman, Şakir; Aksoylu, Ceyhun; Gemi, Lokman; Arslan, Musa Hakan; Hamad, Ahmed Abed; Özkılıç, Yasin Onuralp
Strengthening of shear deficient T-beams is not as easy as rectangular beams due to the presence of slabs. In this study, externally bonded reinforcement (EBR) such type of reinforced concrete shear deficient T-beams with and without anchorage in different CFRP configurations was experimentally and analytically investigated. Pursuant to this goal, nine half-scale T-beams were produced and tested with monotonic loading under four points. Seven of these T-beams are strengthened with partial CFRP strip and one is strengthened with full CFRP wrapped in the shear span. The failures of strengthened beams are initiated with the debonding failure of FRP sheets followed by brittle shear failure. In order to prevent this failure, two specimens with partial CFRP strip are fixed to the beam by using anchors at different angles of 45 and 90. The experimental results indicated that the contribution of EBR to the shear capacity is significant and depends on different variables such as anchorage angle, strengthening type. Moreover, the strengthening method that gives the most effective results in strengthening T-beams are full wrapping CFRP and partial CFRP with a 45-degree anchorage type. The anchorage application increased the shear capacity by 42.6%-53.8% compared to the reference specimens. In addition, the anchors with angle of 45 increased stiffness by 37%. In terms of ductility, the best result was given by the type of strengthening where the slabs were broken and the beam was completely wrapped. This method contributed 42%-80% more to ductility than other methods. The obtained experimental results were also compared with the empirical correlations given by ACI 440.2R-17, TBEC-2019 and FIB-2010 and recommendations are given. Especially in fully wrapped beams, the estimation of ACI was determined to be 96%. The estimations of the other codes are far from meeting the experimental results; therefore, essential improvements should be applied to the codes, especially with regard to CFRP deformation and approaches for anchored connections.
Citation - WoS: 1
Citation - Scopus: 2
Artificial Intelligence Based High Voltage Cable Bonding To Prevent Cable Termination Faults
(ELSEVIER SCIENCE SA, 2020) Akbal, Bahadır
Cable termination fault (CTF) is a major problem for high voltage cable lines (HVCL). Increasing of the sheath voltage (SV), zero sequence current (ZC) and current harmonic distortion (THDI) on metallic sheath (MS) of HVC are major factors for CTF. MS is grounded according to IEEE 575-1988 standard to reduce SV. However, these methods are not sufficient to prevent CTF based on ZC and THDI. The aims of this paper are minimization of SV, ZC and THDI to prevent CTF based on ZC and THDI. Thus, LSSB method is developed as a new bonding method. Also, LSSB parameters should be optimized to make the most economical and practical bonding. GA, DEA, PSO and iPSO are used optimization methods for optimization of LSSB. SV and THDI should be known for optimization of LSSB, so the forecasting methods (FM) are used as fitness function of optimization methods in LSSB optimization. The regression and hybrid artificial neural network methods are compared to determine the most suitable FM. When the optimized LSSB is used for bonding of long HVCL, SV reduces approximately 90%, ZC reduces approximately 93%, and THDI reduces approximately 70%. Thus CTF risk is minimized by using the optimized LSSB in HVCL.
Citation - WoS: 14
Citation - Scopus: 15
Assessing the Structural Behavior of Reinforced Concrete Beams Produced With Macro Synthetic Fiber Reinforced Self-Compacting Concrete
(Elsevier Science Inc, 2022) Ünal, Alptuğ; Uğur, Ahmet Emin
This study was carried out to investigate the effect of polypropylene-based structural macro synthetic fiber (PPF) reinforcement on the behavior of reinforced concrete beams produced with self-compacting concrete (SCC). For this purpose, it was aimed to spread the PPFs homogeneously in the concrete by making use of the fluid form of SCC. The variation of non-fibrous-low-medium-high PPF ratios and stirrup ratios in specimens produced with SCC are the variables of the study. In this study, the shear span/effective depth ratio (a/d) was taken as the limit value of 2.5 in terms of shear and bending, and the behavior of reinforced concrete beams at this critical value was investigated. Within the scope of the study, 16 large-scale specimens were tested under monotonic loads in a 4-point bending setup. Load-displacement, stiffness and energy consumption graphs of the tested specimens were drawn, ductility values were determined, crack distributions were examined and failure modes were determined. The graphs and the determined values were interpreted in detail. In addition, numerical models of the tested specimens were created and analyzed using a finite element program. Experimental study results were compatible with numerical analysis results and similar results were obtained. According to the results obtained, it was observed that the specimens produced with SCC and using PPF reinforcements at appropriate ratios (5 kg/ m3 and 10 kg/m3) exhibited bending failure even if stirrups were not used.
Citation - WoS: 26
Citation - Scopus: 25
An Assessment of Deterioration in Cultural Heritage: the Unique Case of Eflatunpinar Hittite Water Monument in Konya, Turkey
(SPRINGER HEIDELBERG, 2020) Bozdağ, Ali; İnce, İsmail; Bozdağ, Ayla; Hatır, M. Ergün; Tosunlar, M. Bahadır; Korkanç, Mustafa
Stone monuments are important symbols of cultural heritage of countries. However, many environmental factors negatively affect these monuments. The increasing damage on the stone monuments and the danger of irreversible loss of cultural heritage have resulted in growing efforts for the preservation of the monuments. Eflatunpinar Hittite Water Monument in Beysehir, Konya, Turkey, is a unique Hittite cultural monument that has survived for nearly 3200 years even though it has been exposed to many environmental effects. In this study, non-destructive testing (NDT) was used to detect the degradation on the building stones of the Eflatunpinar Hittite Water Monument and change-deterioration maps were prepared subsequently. It was also investigated whether the chemistry of the Eflatunpinar spring water may cause deterioration. Additionally, the petrographic, chemical, and physico-mechanical properties of the rocks taken from the ancient stone quarry were determined in order to compare with the properties of the monument's building stones. Based on the physico-chemical characteristics of the Eflatunpinar spring water and XRD results of crusts in building stone surface of the monument, it was identified that water can be effective on the formation of calcite and gypsum crusts especially in the lower parts of the monument. However, applied NDT methods and change-deterioration maps indicated that the deterioration as well as neglect and abandonment in the monument are mostly associated with the capillary effect of the flowing water through the structure and the deterioration effect is more apparent in contact points between the building stone and the flowing water. Additionally, in the building stones above the capillary front, the conservation condition is significantly better.
Citation - WoS: 9
Citation - Scopus: 8
Atmospheric and Anthropogenic Deterioration of the Ivriz Rock Monument: Eregli-Konya, Central Anatolia, Turkey
(SPRINGER HEIDELBERG, 2021) Korkanç, Mustafa; İnce, İsmail; Hatır, Mehmet Ergün; Tosunlar, Mehmet Bahadır
The aim of this study is to determine the extent of deterioration of the limestone on which the Ivriz rock monument is engraved. This monument is near Aydinkent (Ivriz) village and located 12 km from the Eregli district of Konya. The height of the Ivriz Hittite monument is 4.20 m and its width is 2.40 m. It dates back to the second-half of the eighth century BC. The rocks on which the reliefs are engraved are limestone; the lower parts are brecciated with open cracks, and the upper parts show fewer cracks with smaller gaps. To enable the identification of the characteristics of the rocks on which the figures are located, non-destructive methods were used. Surface humidity, P wave velocity, thermal imaging, and Schmidt hardness measurement were applied to the wall surface of the monument, and mapping studies were conducted. Surface humidity varied between 26 and 58% with the highest values measured in the sections where the cracks are densest. The P wave velocity measured at the rock monument varied between 1.6 and 5.8 km/s, with the lowest values found in the sections where cracks were denser. Schmidt rebound values varied between 18 and 42, with higher values obtained in those sections with fewer effects of deterioration. According to the detailed observations and data obtained from non-destructive techniques (NDT) and laboratory data, the most significant deterioration has resulted from atmospheric conditions and damage by humans. The most common effects of degradation in this area are erosion by water, granular disintegration, cracks, microkarst, black crust, biodegradation (lichen, algae, and higher plants), and vandalism.

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