Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Çolak, Murat(8)
- Bayram, Sinan(5)
- Öner, Erdal(5)
- Can, Zehra(4)
- Ecem Bayram, Nesrin(4)
- Kolaylı, Sevgi(4)
- Turan, Muhittin(4)
- Demirtaş, Betül(3)
- Dispinar, Derya(3)
- Erbayrak, Engin(3)
- Gumus, Beril Eker(3)
- Kamiloğlu, Aybike(3)
- Türker, Temel(3)
- Yanik, Yusuf(3)
- Yuncuoglu, Ercument Ugur(3)
- Özdemir, Akın(3)
- Şahin, Engin(3)
- Aymelek, Abdullah(2)
- Birinci, Ahmet(2)
- Dertli, Enes(2)
- Ergün, Mustafa(2)
- Eryılmaz Türkkan, Gökçen(2)
- Gerçek, Yusuf Can(2)
- Gul, Volkan(2)
- Gıdık, Betül(2)
- Kahraman, Yusuf(2)
- Kamiloglu, Aybike(2)
- Kara, Yakup(2)
- Keskin, Merve(2)
- Kul, S.(2)
- Malgaca, Levent(2)
- Nabiyev, Vasif(2)
- Oktay, Mine Gül(2)
- Sefaoglu, Firat(2)
- Turhal, Uğur(2)
- Uslu, Emin(2)
- Uyar, Mehmet(2)
- Uzun Yaylacı, Ecren(2)
- Yaylacı, Murat(2)
- Özkök, Aslı(2)
Yayınlar
- MakaleAçık Erişim2025Scopus SJRQ2Detailed investigation of the spectroscopic features of nicardipine hydrochloride using experimental and quantum chemical methods
Can, Sumeyra; Cinar, Mehmet; Baris, Ozlem
Context: The structural and spectroscopic properties of drug groups can be determined using spectroscopic techniques and quantum chemical calculations. In this study, the structural and spectroscopic properties of nicardipine, a potent calcium channel blocker belonging to the dihydropyridine drug group, were investigated. For this purpose, FT-IR, Raman, NMR, and UV–Vis spectra of nicardipine hydrochloride were recorded. The ground state geometry optimization performed under vacuum conditions showed excellent agreement with X-ray diffraction (XRD) data, with root-mean-square deviations of bond lengths and bond angles calculated as 0.017 Å and 2.2°, respectively. Vibrational spectrum analysis revealed all characteristic modes, and theoretical B3LYP predictions largely agreed with experimental data. NMR spectra recorded in chloroform solvent confirmed the molecular structure of nicardipine. A comparison with previously reported data revealed significant differences in the proton NMR results, while the carbon NMR data showed consistency. The gauge-invariant atomic orbital (GIAO) method, commonly used for NMR spectrum prediction, yielded results within an acceptable error range despite minor inconsistencies arising from differences between experimental and computational conditions. In the UV–Vis spectrum of nicardipine HCl, an absorption peak corresponding to π-π* excitation was observed at 238 nm. Method: The geometric optimizations and vibration spectra of the nicardipine drug molecule were performed using the Gaussian 09 program with the B3LYP functional and the 6–311 + + G(d,p) basis set. Visualizations were performed using the GaussView 5.0 interface program. NMR spectra were recorded in chloroform solvent using the GIAO method. Molecular electrostatic potential (MEP) maps and Mulliken atomic charges were analyzed to gain deeper insight into the electronic properties.
AtıfScopus1WoS1OpenAlex1
İncele - MakaleAçık Erişim2025Scopus SJRQ2Investigation of the Effects of Filling Speed, Casting Temperature and Metallurgical Quality on Fluidity of Lamellar Graphite Cast Iron at Different Section Thicknesses
Köse, Sami; Çolak, Murat; Şüküroğlu, Ebru Emine
In this study, the fluidity properties of the alloy were investigated at different casting temperatures, different section thicknesses, and varying casting parameters of lamellar graphite cast iron materials. To achieve our goal, we utilized sand molds that were created with specific parameters including pouring temperature, metallurgical quality, section thickness, and fluidity test model. These molds were used for casting. Thus, the effect of fluidity properties in changing casting conditions and liquid metal advance distances at determined section thicknesses was investigated. Modeling was carried out with FlowCast casting simulation software by determining the liquid metal advance distance depending on the section thickness in the castings made in sand molds under changing casting conditions. The fluidity and advance distance of the liquid metal was determined comparatively with experimental and modeling techniques under the changing casting conditions in the parameters determined in this study. When the outcomes were examined; it was observed that different liquid metal advance distances occur at different cross-section thicknesses depending on the changing conditions.
AtıfScopus8WoS8OpenAlex7İncele - MakaleYalnız künye2025Scopus SJRQ2Semi-analytical analysis of orthotropic-isotropic contact in layered media with consideration of body forces
Öner, Erdal; Oktay, Mine Gül
Contact mechanics is a key field that involves theoretical, computational, and experimental methods essential for tribology and designing components across various industries. It plays a crucial role in solving boundary value problems in civil engineering, mechanical engineering, and medicine. This study investigates the continuous contact problem of an orthotropic layer positioned on an isotropic half-plane, utilizing a semi-analytical approach based on elasticity theory. The solution considers the body force generated within the orthotropic layer when subjected to frictionless loading by a rigid cylindrical punch. The research presents dimensionless results for key parameters, including contact length, contact stress, critical separation distance, and critical separation load, while examining the effects of different dimensionless variables and the characteristics of the orthotropic materials. The novelty of this study lies in its simultaneous analysis of isotropic and orthotropic material behavior in a contact mechanics problem, along with the incorporation of body forces—a combination that has not been previously explored for this specific geometry in the literature. The study offers a more comprehensive understanding of the contact mechanics involved by addressing the often-overlooked influence of body forces, which play a crucial role in stress distribution and material deformation, particularly in large-scale structures. This inclusion allows for more accurate predictions of material behavior in real-world engineering applications where gravitational loads are significant factors.
AtıfScopus4WoS4OpenAlex4İncele - MakaleAçık Erişim2025Scopus SJRQ2The effect of training given to patients who underwent ureteroscopy with double-J stent placement on anxiety before and after surgery and readiness for discharge
Toraman, Muazzez Merve; Gürçayır, Dilek
Patient education is effective in reducing the level of anxiety before and after surgery and increasing the level of readiness for discharge. Patient education provided by nurses can be planned and applied individually. Therefore, this study aims to determine the effect of the education in whom a double J stent after ureteroscopy on their pre- and postoperative anxiety and levels of readiness for discharge. This research study is a randomized controlled trial with control and intervention groups, pre- and posttests. This study was conducted between November 2021 and May 2022 in a university hospital in Turkey. The patients were divided at random into two groups, control (n = 61) and intervention (n = 61). The Personal Information Form, State-Trait Anxiety Inventory (STAI-I, STAI-II), Surgery-Specific Anxiety Scale (SSAS), Readiness for Hospital Discharge Scale for Adult Patients-Short Form (RHDS/SF) and Readiness for Hospital Discharge Scale- Adult-Nurse Assesment Short Form (RN-RHDS/SF) were used to collect the data. The mean SSAS and STAI-I scores on the morning of surgery and before discharge were found to be significantly lower in the intervention group than the control group. The mean RHDS/SF and RN-RHDS/SF scores on the before discharge were found to be significantly higher in the intervention group than the control group. It was concluded that the education provided to the patients in whom a double J stent after ureteroscopy reduced pre- and postoperative anxiety and increased the level of readiness for discharge.
AtıfScopus5WoS3OpenAlex6İncele - MakaleAçık Erişim2025Scopus SJRQ2Contact mechanics of functionally graded orthotropic layer under normal traction and gravity: an analytical perspective
Öner, Erdal; Al-Qado, Ahmed Wasfi Hasan
Contact mechanics is a complex and advanced field of engineering, with continuous research dedicated to modeling and examining contact problems in multilayered and multibody systems. Given that fatigue and fracture failures often result from contact loads, precise determination of subsurface stresses is crucial for the design of mechanical components. This study provides an exact analytical solution for the frictionless indentation of a functionally graded (FG) orthotropic layer by a rigid cylindrical punch. The FG orthotropic layer, which rests on a rigid, non-adhesive substrate, is treated as a nonhomogeneous medium with an orthotropic stress–strain relationship. Part of its top surface experiences normal tractions, while the rest remains traction-free. The analysis also incorporates the gravitational force affecting the FG orthotropic layer. Five distinct real orthotropic materials are used, each with individually graded stiffness constants in their principal directions, to define the FG orthotropic behavior of the material. The governing equations are formulated using the singular integral equation method and transformed into algebraic systems via the Gauss–Chebyshev integration technique. A comprehensive parametric study examines how variations in dimensionless punch radius, compressive force, inhomogeneity parameters, and body force influence contact widths, contact pressures, normal and shear stresses, critical load factor, and the initial point of interface separation.
AtıfScopus9WoS9İncele - MakaleAçık Erişim2025Scopus SJRQ2Tri-method analysis of contact mechanics in orthotropic-isotropic materials
Öner, Erdal; Oktay, Mine Gül; Uzun Yaylacı, Ecren; Yaylacı, Murat; Mirzaloğlu, İrem
This study examines the contact mechanics of a homogeneous orthotropic layer resting on a homogeneous isotropic half-space without being bonded, subjected to loading by a rigid cylindrical punch. The effect of the orthotropic layer’s body force has been taken into account in the study. The study is conducted in three phases. In the first phase, the contact problem is analytically tackled using advanced methods such as elasticity theory, integral transform techniques, and Gauss–Chebyshev integration. The second phase utilizes finite element analysis through ANSYS software, accurately modeling the system. In the final phase, an artificial neural network is employed, allowing the system to learn and recognize intricate patterns in the data. The standout feature of this study is its thorough comparison of these three distinct methodologies, offering a comprehensive understanding of the contact mechanics between isotropic and orthotropic materials. The results reveal key insights into contact length, maximum contact stress, critical separation load, and separation distance, all as functions of critical dimensionless parameters. This study is significant in today’s advancing field of contact mechanics as it not only explores the combined impact of body forces and the interaction between orthotropic and isotropic materials but also uniquely compares the results using three distinct methods, offering comprehensive insights that address both theoretical and practical challenges.
AtıfScopus27WoS27OpenAlex22İncele - MakaleAçık Erişim2025Scopus SJRQ2Bending and Buckling Analysis of Porous 2D Functionally Graded Beams with Exponential Material Property Variation
Adiyaman, Gökhan; Turan, Muhittin
The bending and buckling analysis of porous two-directional (2D) functionally graded (FG) beams was conducted using a higher-order shear deformation theory. The introduction of exponential functions to depict changes in material properties is a novel approach in the static analysis of 2D FG beams. Three distinct porosity distribution functions were taken into account. The governing equations were formulated through the application of Lagrange’s principle. During the numerical analysis, a finite element comprising two nodes and eight degrees of freedom was utilized. This choice facilitated accurate and efficient solutions, even for shorter beams, without the need for a shear correction factor. Notably, the obtained shear stresses aligned with actual values, registering as zero at both the top and bottom of the beam. The obtained results of the study were validated against findings reported in the literature. A parametric study was carried out to investigate the effects of porosity, porosity distributions, gradation parameters, slenderness, and boundary conditions on the non-dimensional deflections, stresses, critical buckling loads, and buckling mode shapes. It was found that both porosity and the distribution of porosity have noticeable effects on the static analysis of the beams.
AtıfScopus18OpenAlex13İncele - BildiriAçık Erişim2025Scopus SJRQ4Lightweight Hybrid CNN Model for Face Presentation Attack Detection
Turhal, Uğur; Yilmaz, Asuman Günay; Nabiyev, Vasif; Mammadova, G.; Aliev, T.; Aida-zade, K.
Today, face recognition systems are widely used in many areas that require biometric-based verification, especially because they are contactless and require low user cooperation. Despite their ease of implementation, these systems are vulnerable to attacks. Especially the increasing use of social media, makes it easier to spoof face recognition systems. Therefore, it is very important to develop new methods for Face Presentation Attack (FPA) detection. In this study, FPA detection performances of the lightweight Convolutional Neural Network (CNN) models -MobileNetV3-Small, ShuffleNet, SqueezeNet- and lightweight hybrid CNN models designed with combinations of these networks were investigated. In the experiments, the change in FPA detection performance was examined by giving the cropped face regions and the whole images as input to the networks. Using the whole image instead of the cropped face region significantly improved the FPA detection performance of the CNN models. These results showed that non-facial areas carry important information in FPA detection. Also, the FPA detection performance of the proposed lightweight hybrid CNN models were better than the single use of the networks for both inputs. 0.17% HTER performance was achieved with the hybrid CNN model built from the combination of ShuffleNet + SqueezeNet on the Replay-Attack dataset.
- MakaleAçık Erişim2025Scopus SJRQ2Investigation of the Effect of Vanadium Addition on Mechanical Properties in A356 Aluminum Casting Alloys
Çeker, Merve; Çolak, Murat
The superior properties of aluminum alloys are further improved by the addition of different elements and gain new qualities. In the aluminum casting industry, vanadium (V) addition plays an important role to improve the mechanical and physical properties of these alloys. In this study, different amounts of V (0.03%, 0.06% and 0.1%) were added to A356 alloy, and its effects on mechanical properties and microstructure were investigated experimentally. The liquid metal degassing process was applied in all experiments in order not to affect the results of gases and inclusions in the liquid metal before casting. In the study, degassing was assessed by the Reduced Pressure Test (RPT). Tensile and hardness test specimens were performed with specimens obtained from mechanical test molds. When the results were examined, the elongation amount, which was 2.7% in A356 casting without addition, increased with the addition of V and reached a maximum value of 7.6% with 0.1% V addition. Tensile stress values were 137 MPa in A356 castings without addition, 159 MPa with 0.03% V addition, 168 MPa with 0.06% V addition and increased up to 185 MPa with 0.1% V addition.
AtıfScopus5WoS5OpenAlex5İncele - MakaleYalnız künye2024Synergistic Strategies for Overcoming Salt Stress in Strawberry Farming: The Use of Organic Fertilizers and Plant Growth Promoting Rhizobacteria (PGPR)
Yavuz, Aysegul; Erdogan, Ummugulsum; Turan, Metin; Argın, Sanem; Kocaman, Ayhan
The study was carried out under salt-stress conditions, and three non-microbial commercial organic fertilizers purchased from Humintech GmbH (Grevenbroich, Germany) were applied to the soil for strawberry plants. The three promoters were Fulvagra®, based on fulvic acid, Liqhumus®, based on humic acid, and Microsense Root®, also based on humic acid. Treatment with Fulvagra® resulted in a remarkable 69.90% increase in average fruit weight and a 39.52% increase in yield in strawberry plants. These improvements remained significant when combined with plant growth promoting rhizobacteria (PGPR), resulting in a 61.81% increase in fruit weight and a 45.21% increase in yield. Liqhumus® treatment resulted in a significant 49.95% increase in fruit weight and a 39.30% increase in fruit yield. The introduction of PGPR further enhanced these effects by increasing fruit weight by 87.70% and yield by 63.84%. The Microsense Root® treatment showed 31.07 and 61.87% improvements for the respective parameters. In conjunction with this treatment, the use of PGPR produced the most significant results, with increases of 121.14 and 65.37% for respective parameters. These results indicate that the combined use of non-microbial commercial organic fertilizers with PGPR leads to higher efficiency and is promising for sustainable agricultural practices, particularly in improving the resistance of strawberry plants to salt-induced stress.
AtıfScopus4WoS5OpenAlex5İncele - MakaleYalnız künye2024Scopus SJRQ2A comparative anatomical study on leaf and scape of Androsace taxa (Primulaceae): contribution to Androsace taxonomy
Ulcay, Sibel; Sefali, Abdurahman; Yapar, Yakup; Demir, İbrahim; Gıdık, Betül
In the present study, the leaf and scape anatomical features of ten Androsace taxa distributed in Türkiye were defined to contribute to plant identification. Hand sections from both the scape and leaf examined 43 anatomical characters. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were performed for the first time for Androsace. The results show that there are differences as well as similarities between Androsace species. It is noteworthy that Androsace artvinensis forms a separate main group with HCA. In addition, the fact that two of the five basic components are represented by a single variable according to the PCA results suggests that the anatomical characters examined are determinative for Androsace taxa.). In PCA, eigenvalues of PC1 (2.435), PC2 (1.749), PC3 (1.369), PC4 (1.223), and PC5 (1.006) were greater than 1.0. Cortex width, aerenchyma, arrangement of vascular bundles, and four-branched non-glandular hairs are among the important anatomical characteristics of the scape. Leaf cross-sectional shape, epidermis dimensions, glandular hair types, presence of five branched non-glandular hairs, stoma sizes, presence of crystals in the mesophyll, and types are among the qualitative and quantitative anatomical characteristics that attract attention in the leaf. This study examined almost all taxa of the genus Androsace distributed in Türkiye. The results will be important in finding new species among the examined taxa and revealing the anatomical features of the taxa for the first time. They will contribute to other studies on the genus.
AtıfScopus1İncele - MakaleYalnız künye2024Scopus SJRQ2Effect of different carbon sources on exopolysaccharide production of Lactiplantibacillus pentosus KS27 and optimization of production conditions using Box-Behnken designing
Bekar, Fevzi; Kamiloglu, Aybike
This study aimed to determine the exopolysaccharide (EPS) production of Lactiplantibacillus pentosus KS27 depending on temperature, incubation time, and medium composition and to determine the optimum conditions. Characterization was carried out for the exopolysaccharide produced under optimum conditions. In the study, three different conditions (25 °C, 35 °C, 45 °C) were used for temperature, glycerol, and sucrose as media, and three different periods (24 h, 36 h, and 48 h) were used. It was determined that the solubility of EPS produced under optimal conditions had the highest water content (98 ± 0.01%), while the water binding capacity was also found to be as high as 1970 ± 0.01% and complied with common EPS characteristics. Differential scanning calorimeter analysis showed a gradual deterioration up to 191.88 °C and a slow decline up to 400 °C. FTIR analysis deciphered peak values between 3289 and 517 cm−1, and functional groups were detected. When the nuclear magnetic resonance (NMR) spectrum was examined, a heterogeneous structure appropriate to the structure of EPS was found by defining the peak entities in three separate regions.
AtıfScopus5WoS5OpenAlex6İncele - MakaleAçık Erişim2024Scopus SJRQ3Teachers’ Attitudes Towards Inclusive Education: a Cross-National Exploration
Charitaki, Garyfalia; Kourti, Isidora; Gregory, Jess L.; Ozturk, Mesut; Ismail, Zaleha; Alevriadou, Anastasia; Soulis, Spyridon-Georgios; Sakici, Şehnaz; Demirel, Can
The study aims to suggest a model for attitudes towards inclusive education that will yield a good fit across different countries. Moreover, we aim to explore the effect of years of teaching experience, educational work level of teachers, and the highest degree completed by teachers on teachers’ attitudes towards inclusion across different countries. A demographic scale and the ATTAS-mm were applied to 908 teachers employed in schools of general education or who offered parallel support and/or resources in five different countries (Greece, the UK, the USA, Malaysia, and Turkey). CFA suggested a 4-factor solution, which included the cognitive, affective, and behavioral factors that have been previously introduced by Gregory and Noto (2012), and a fourth factor, labeled overall attitudes towards teaching all students. In the cognitive factor, the UK had the most positive attitudes. TU, MA, and GR enrolled in the same cluster, and the USA had the least positive attitudes. In the affective factor, GR had the most positive attitude. MA and the USA enrolled in the same cluster and TU and the UK had the least positive attitudes. A similar pattern is observed for the behavioral factor with GR having the most positive attitude. TU and MA enrolled in the same cluster, and the USA and the UK had the least positive attitudes. Finally, years of teaching experience, educational work level, and the highest degree completed have a significant effect on teachers’ attitudes towards inclusion in all countries. Providing feedback for future research is the focal point of the discussion part.
AtıfScopus52OpenAlex54İncele - MakaleAçık Erişim2024Scopus SJRQ2Mixed series solution for vibration and stability of porous bi-directional functionally graded beams
Turan, Muhittin
A new analytical solution based on the Ritz method is presented in this paper for analyzing the free vibration and buckling behavior of porous bi-directional functionally graded (2D-FG) beams under various boundary conditions. The solution is based on first-order shear deformation theory (FSDT). The selection of solution functions used in Ritz methods distinguishes the methods from each other and determines the accuracy of the analytical solution. To accurately capture the system's behavior and achieve the desired results, these functions have been carefully selected as a combination of polynomial and trigonometric expressions tailored as mixed series functions for each boundary condition. The study considers three types of porosity, namely PFG-1, PFG-2, and PFG-3. The equations of motion are derived using Lagrange's principle, taking into account the power-law variation of the beam material components throughout the volume. The non-dimensional fundamental frequencies and critical buckling loads are calculated for different boundary conditions, gradation exponents in the x and z directions (px, pz), slenderness (L/h), porosity coefficient (e), and porosity types. Initially, the accuracy of the mixed series functions is investigated for non-porous bi-directional functionally graded beams, and the numerical results are compared with existing literature to validate the proposed solution. Subsequently, the paper focuses on analyzing the influence of porosity on the free vibration and buckling behavior of bi-directional functionally graded beams using the developed solution method.
AtıfScopus21WoS22OpenAlex18İncele - MakaleAçık Erişim2024Scopus SJRQ1Determination of phenolic content and bioactive characterization of Anatolian propolis
Can, Zehra; Birinci, Ceren; Kara, Yakup; Esertaş, Ülkü Zeynep Üreyen; Kolaylı, Sevgi
In this study, propolis referred to as of Türkiye Anatolian propolis was utilized. This work was aim to prepare a 70% ethanolic extract of propolis and subsequently determine certain biochemical parameters, total phenolic content (TPC), total flavonoid content (TFC), phenolic and flavonoid composition, inhibitory effects on certain enzymes [acetylcholinesterase (AChE), urease, and alpha-amylase], along with assessments of antiviral activity against Vero cells, lung cancer cells (A549), and breast cancer cells (MDA-MB-231). The richness of phenolic content in Anatolian propolis clearly indicates a high inhibitory effect on these enzymes. Additionally, it was observed to exert significant effects on cancer cells and demonstrated effective antiviral activity. It can be contemplated that the Anatolian propolis might serve as a potential source for novel drugs, and the isolation of its compounds could offer opportunities for utilization in traditional medicine.
AtıfScopus9WoS10OpenAlex11İncele - MakaleAçık Erişim2024Olive Oil Production Forecasts for a Macro Perspective during 2024–2027
Kurtoğlu, Seval; Uzundumlu, Ahmet Semih; Gövez, Elif
Olive oil, which is part of the Mediterranean diet, is one of the most important foods for a healthy diet. The number of countries that produce these important foods has not increased significantly over the years. However, the number of exporting countries tripled in the same period. This study aimed to predict the countries that will lead olive oil production globally between 2024 and 2027 by using the production data from the period 1961–2023. The data were analyzed using the ARMA model in the statistical program SAS. According to the results for the 10-year period of 1961–1970, there were 25–26 olive-oil-producing countries in the world. Approximately 31.26% of olive oil production was in Italy, 28.32% in Spain, 13.14% in Greece, 7.80% in Turkey, and 5.74% in Portugal. According to the average production for the period 2024–2027, it is estimated that 34 and 35 countries will produce olive oil, with 29.93%, 9.08%, 9.06%, 9.00%, and 8.90% of the world’s production provided by Spain, Greece, Turkey, Morocco, and Italy, respectively. These five countries account for 65.96% of the world’s production level. The estimation results of this study found that there are many exporting countries other than the leading producer countries thus showing that the producer countries do not have a forceful marketing concept, and therefore intermediaries emerge. For this reason, producer countries such as Turkey, Tunisia, and Morocco, which are not very competent in marketing, will have more say in the market by using their resources more effectively and making more effective strategies with an improved production and marketing approach.
AtıfScopus27WoS28OpenAlex30İncele - MakaleYalnız künye2024Scopus SJRQ2A new face presentation attack detection method based on face-weighted multi-color multi-level texture features
Turhal, Uğur; Günay Yılmaz, Asuman; Nabiyev, Vasif
Biometric data (facial, voice, fingerprint, and retinal scans, for example) are widely used in identification due to their unique and irreversible nature. Facial recognition technologies are employed in a wide range of applications due to their contactless nature and convenience. However, technological advancements and the availability of access to personal information have rendered these biometric systems susceptible to attacks utilizing fake faces. As a result, the issue of anti-spoofing has emerged as a critical one in the field of facial recognition. This study proposes a joint face presentation attack (FPA) detection method based on face-weighted multi-color multi-level LBP features extracted from the combination of device-dependent HSV and device-independent L*a*b* color spaces. The facial images were converted to HSV and L*a*b* color spaces. Three levels of regional LBP features were extracted from each color channel and then concatenated. Finally, a Multi-Color Multi-Level LBP (MCML_LBP) feature vector was obtained. In addition, the Face Weighted MCML_LBP feature vector was produced (FW_MCML_LBP) by adding the LBP histogram extracted from the central region of the normalized image. The feature vectors are used to train an SVM classifier after reducing their size using PCA. Twenty-five different test scenarios were subjected to experimentation on the CASIA and Replay-Attack databases. 2.11% EER and 0.19% HTER were achieved on CASIA (Overall) and Replay-Attack (Grandtest) databases, respectively, using the L*a*b color space and the proposed feature extraction method. The results of the study showed that the proposed method was successful in FPA detection compared to the state-of-the-art methods.
AtıfScopus11WoS10OpenAlex10İncele - MakaleYalnız künye2024Scopus SJRQ2Optimization, Characterization, and Carbon Footprint Analysis of Alkali Activated Waste Tuff and Fly Ash Mixtures for Deep Mixed Columns
Kamiloğlu, Hakan Alper; Yilmaz, Fatih
Deep soil mixing (DSM) applications are one of the widely known soil stabilization techniques which can be applied to a wide range of soil types. Cement and lime are the major materials used as binders for DSM applications. However, as conventional binders lead to emit a large amount of CO2 during production, eco-friendly binders suitable for DSM applications have become prominent. Alkali-activated materials are good alternatives to conventional binders. This study was intended to investigate the usability of zeolite rich tuff wastes as an alkali-activated binder in DSM columns. Within this scope, the waste tuff and C-type fly ash mixture were used as an alkali-activated binder, and 10 M NaOH solution was used as an activator. Response surface methodology (RSM) was employed in experimental design to determine optimum components to obtain maximum unconfined compression strength and investigate the interaction between stabilization agents. From the RSM analysis the optimum ratios of activator (X1), waste tuff (X2), and precursor (X3) were determined as; X1 = 0.251, X2 = 0.548, and X3 = 0.538 for maximum UCS. UCS, mineralogical and microstructural characterization (XRF, XRD, SEM, EDX, FTIR) was performed for the DSM samples prepared considering the optimized components. It was determined that the UCS values of the 3, 7, and 28-day cured samples stabilized by considering the optimum values gave UCS values approximately 3 to 5 times higher than the lower limit values recommended by FHWA. As a result of mineralogical and microstructural investigation, the reason for the strength increase in the samples can be attributed to the formation of geopolymeric gel between the soil particles by tuff waste and fly ash activated with alkaline activator. Carbon footprint analyses were performed for 1m3 DSM columns produced with alkali-activated binders and ordinary Portland cement (OPC). From the analyses it was seen that the carbon footprint of the DSM column produced using alkali activated binders is lower than that of the DSM column obtained with OPC. After the general evaluation of the study, it is seen that the hypothesis that waste tuff can be used as environmentally safe alkali-activated binders instead of traditional binders is supported.
AtıfScopus6OpenAlex6İncele - MakaleYayıncıda açık erişim2024Scopus SJRQ2Generalized strongly n-polynomial convex functions and related inequalities
Özcan, Serap; Kadakal, Mahir; İşcan, İmdat; Kadakal, Huriye
This paper focuses on introducing and examining the class of generalized strongly n-polynomial convex functions. Relationships between these functions and other types of convex functions are explored. The Hermite–Hadamard inequality is established for generalized strongly n-polynomial convex functions. Additionally, new integral inequalities of Hermite–Hadamard type are derived for this class of functions using the Hölder–İşcan integral inequality. The results obtained in this paper are compared with those known in the literature, demonstrating the superiority of the new results. Finally, some applications for special means are provided.
AtıfScopus5WoS5OpenAlex6İncele - MakaleYalnız künye2024A Comparative Study on the Bioactivity and Mineral Content of Different Grapevine (Vitis vinifera L.) Leaves Cultivated in Türkiye
Yildiz, Hilal; Cakir, Ozlem; Cakiroglu, Kubra; Karatas, Neva
The mineral composition, total phenolic content, radical scavenging, and antibacterial activity of 17 Vitis vinifera L. leaves obtained from vineyards in northeast Türkiye were investigated in this study. The antibacterial activities of grapevine leaf extracts were investigated by the disk diffusion method against five bacterial strains, and all leaf extracts showed inhibitory activity on both Bacillus cereus and Staphylococcus aureus. The radical scavenging activity of grapevine leaf extracts was evaluated using the DPPH (2,2-diphenyl-1-picryl hydrazyl) and ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid) assays. The ‘Gineş’ cultivar had the highest level of radical scavenging activity, while the ‘Ciklap’ cultivar had the lowest. The total phenolic content of leaf extracts was in the range of 172.66–483.33 µg GAE/mg DW. Grapevine leaf extracts were examined in terms of 15 different elements. The most abundant element in varieties of grapevine leaves was potassium, and its concentration varied between 5208.83 and 13,586.49 mg/kg. The results indicated that V. vinifera L. leaves had strong antioxidant and antibacterial activity, and the varieties of grapevine had a significant impact on these parameters (p < 0.001). Mineral and trace element contents were also significantly affected by cultivars (p < 0.05).
AtıfScopus6WoS5OpenAlex6İncele