Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Gul, Muhammet(102)
- Güler, Ömer(69)
- Akkurt, Nevzat(68)
- Tekin, H.O.(52)
- ALMisned, Ghada(49)
- Yucesan, Melih(49)
- Celik, Erkan(45)
- Zengin, Gokhan(40)
- Serdar, Osman(39)
- Kocabaş, Mehmet(37)
- Aslan, Naim(31)
- Baskonus, Haci Mehmet(31)
- Bulut, Hasan(31)
- Mete, Suleyman(31)
- Paksoy, Mehmet Yavuz(30)
- Kök, Mediha(27)
- Ince, Muharrem(26)
- Yildirim, Ozal(26)
- Özkul, İskender(26)
- Sulaiman, Tukur Abdulkadir(25)
- Topal, Murat(25)
- Guler, Omer(24)
- Serin, Faruk(23)
- Benzer, Fulya(22)
- Erten, Fusun(22)
- Alataş, Mevlüt(21)
- Güler, Seval Hale(21)
- Baykal, Duygu Sen(20)
- Taşgın, Yahya(20)
- Kutlu, Banu(19)
- Onat, Onur(19)
- Sahin, Kazim(19)
- Tanyol, Mehtap(19)
- Torğut, Gülben(19)
- Yildirim, Numan(19)
- Kahraman, Gökhan(18)
- Orhan, Cemal(18)
- Say, Yakup(18)
- Susam, Selim Orhun(18)
- Utku, Anıl(18)
Yayınlar
- MakaleAçık Erişim2025Scopus SJRQ2Innovative image encryption approach based on bitwise XOR high nonlinear S-boxes and random permutation
Artuğer, Fırat
With today's developing technologies, the need for new image encryption algorithms to encrypt images is inevitable. In this study, an innovative image encryption algorithm is proposed. The proposed algorithm first XORs each layer of the image with a unique and strong new key. Each layer is then subjected to a random permutation process. Each of the encrypted layers obtained here is finally passed through a new s-box structure with a high nonlinearity value. After these processes, all layers are combined to obtain an encrypted image. Thus, XOR and s-box confusion meet the criteria, while random permutation meets the diffusion criteria. In this study, both key and s-box structures were originally obtained with a chaotic Gaussian map. The outputs of the chaotic map were converted into bit sequences and five different sequences with a length of 1 million were obtained. All these arrays have successfully passed all NIST SP 800-22 tests. On the other hand, the proposed s-box structures surpassed many studies with nonlinearity values of 108, 108.5, and 108.75. The images were successfully encrypted with the proposed algorithm, and the encrypted images successfully completed tests such as NPCR-UACI, information entropy, histogram analysis, and correlation analysis. It is thought that this study will make many contributions to the fields of s-box development, random number generation, and image encryption.
AtıfScopus3OpenAlex3
İncele - MakaleAçık Erişim2025Scopus SJRQ2A Novel CuAlMnFe/CeO2 Composite Alloy: Investigating the Wear and Corrosion Features
Doğan, Fatih; Duru, Erhan
Shape memory alloys (SMAs) are known for their exceptional mechanical properties, particularly their superior wear resistance compared to conventional alloys with similar surface hardness. Rare earth oxides are often used as additives to further improve these characteristics. This study investigates the effects of different CeO2 (cerium dioxide) concentrations (0.01 wt.%, 0.1 wt.%, 0.5 wt.%, and 1.0 wt.%) on the properties of CuAlMnFe alloys produced via powder metallurgy (PM). Various analyses were performed, including scanning electron microscopy (SEM), Energy Dispersive Spectroscopy (EDS), X-ray diffraction (XRD), as well as hardness, wear, and corrosion tests. The increase in wear rate is closely related to the formation of precipitates from CeO2 addition. Improvements in wear resistance and hardness are attributed to the effects of grain refinement and solid solution strengthening due to CeO2. Specifically, the wear rate increased from 1.5 × 10−3 mm3/(Nm) to 3.4 × 10−3 mm3/(Nm) with higher CeO2 content. Additionally, the friction coefficient of the CuAlMnFe alloy was reduced with CeO2 addition, indicating enhanced frictional properties. The optimal CeO2 concentration of 0.5% was found to improve grain uniformity, resulting in better wear resistance. Incorporating CeO2 particles into CuAlMnFe alloy enhances hardness and reduces wear rate when used in appropriate amounts. Additionally, it exhibits superior corrosion resistance, as evidenced by a positive shift in corrosion potential in Tafel measurements in solutions and a decrease in corrosion current density. The C0.5 specimen showed the highest corrosion potential (Ecorr, −588 V) and the lowest corrosion current density (icorr, 6.17 μA/cm2) during electrochemical corrosion in 3.5 wt.% NaCl solution.
AtıfScopus2WoS2OpenAlex2
İncele - MakaleAçık Erişim2024Scopus SJRQ1Mechanical, wear and thermal properties of natural fiber-reinforced epoxy composite: cotton, sisal, coir and wool fibers
Tasgin, Yahya; Demircan, Gokhan; Kandemir, Seckin; Acikgoz, Abuzer
Natural fiber-reinforced epoxy composites (NFRCs) have gained significant attention in recent years due to their potential as environmentally friendly and sustainable materials. These composites combine natural fibers, derived from plants, with epoxy resins to create a material with enhanced properties. The objective of this study is to investigate the mechanical, wear and thermal properties of NFRCs incorporating cotton, sisal, coir and wool fibers. The vacuum-assisted resin transfer molding (VARTM) technique was employed to produce composite plates, followed by conducting tests on tensile, wear and thermal properties. The cotton composite showcased the highest tensile strength, reaching 52.81 MPa, while the coir composite exhibited the lowest, measuring 15.34 MPa. Sisal composite exhibited a moderate wear rate (1.423 mm3/Nm) and a lower coefficient of friction (0.233), implying smoother relative motion. Coir composite presented the highest wear rate (4.615 mm3/Nm), attributed to its coarse fiber nature. Thermal conductivity is highest at cotton composite (1.017 W/mK) and is lowest at coir composite (0.187 W/mK). Additionally, the highest specific heat was observed in the coir composite (26.313 MJ/m3K). Cotton demonstrated potential for efficient heat transfer, while wool outperformed in insulation. Sisal displayed versatility for structural applications. Coir emerged as an effective insulator with energy-saving applications.
AtıfScopus101WoS83OpenAlex102İncele - MakaleYalnız künye2024Scopus SJRQ2Deep learning-assisted Hubble parameter analysis
Salti, Mehmet; Kangal, Evrim Ersin; Zengin, Bilgin
We turn our attention on evaluating the most recent Hubble parameter data measured via the differential evolution of cosmic-chronometers from a deep learning perspective. To achieve this goal, we start our investigation by introducing the selected theoretical setup and compiling the most recent statistical data obtained in cosmology experiments. Then we implement a tuned version of the long-short term memory (LSTM) architecture and run it to predict possible values of the Cosmic Hubble parameter for different red-shift states. Since we observe a good correlation between the observed and predicted datasets of the Hubble parameter, we conclude that the machine learning approaches can play important roles in the future cosmology investigations.
AtıfScopus2WoS2OpenAlex2İncele - MakaleYalnız künye2024Scopus SJRQ1The effect of high entropy oxide on radiation shielding parameters of erbium oxide doped glasses
Kanca, M. Sait; Taşgın, Yahya; Yılmaz, Demet; Pathman, Abdul Fatah; Güler, Ömer
High-entropy materials are one of the most studied topics in recent years due to the extraordinary properties they exhibit. High entropy oxide (HEO) is a group of materials that have been studied for different applications. However, the effects of HEOs on the radiation properties of glasses are not well known. In this study, the structural, radiation and neutron shielding properties of SiO2 glass systems doped erbium oxide reinforced with refractory high entropy oxide (RHEO) with the formula TiMoNbTaWZrO11 were investigated. RHEAs used in the study were produced and characterized in our laboratory. Then, they were added to the glass samples at different rates together with Erbium oxide. As a result of SEM-EDS and XRD analyses, it was determined that the additives were distributed very homogeneously on the glass. The composition of glass systems is [95SiO2+(5-x)Er2O3+x TiMoNbTaWZrO11], where (x = 0, 0.5, 1 and 2 %, mol). The linear and mass attenuation coefficients (LAC and MAC), mean free path (MFP), half-value layer (HVL) and effective atomic numbers (Zeff) and effective electron density (Nel) of the glass structures were experimentally measured at the energy region of 53.16–661.62 keV. Also, the equivalent dose rates due to fast neutrons absorption were measured by using an 241Am–Be fast neutron source. Exposure buildup factor (EBF) and fast neutron removal cross section (ΣR) were theoretically determined. The proton and alpha shielding parameters of glasses were calculated. It is observed that glasses containing higher amounts of refractory high entropy oxide, within the SiO2–Er2O3 composition, demonstrated enhanced capabilities for shielding against radiation and neutrons.
AtıfScopus15WoS15OpenAlex17İncele - MakaleYalnız künye2024Scopus SJRQ1Nutrification and fat reduction of deep-fried protein isolates
Erol, Nida Demirtas; Cakli, Sukran; Szymczak, Mariusz; Shen, Cangliang; Matak, Kristen E.; Jaczynski, Jacek
Deep-fried (DF) foods are considered nutritionally-inferior due to increased fat content, although they are popular with consumers due to desirable sensory characteristics. This study attempted to reduce fat of DF surimi, DF fish-protein-isolate (FPI), and DF chicken-protein-isolate (CPI) by pre-baking or pre-roasting. Surimi, FPI, and CPI were also nutrified with ω-3-rich oil, fiber, and KCl-based salt substitute. Pre-baking decreased (p < 0.05) fat content, while pre-roasting increased (p < 0.05) it. Pre-baking resulted in less (p < 0.05) changes to cook loss, moisture loss, expressible moisture, water-holding-capacity, whiteness, and texture when compared to pre-roasting. Pre-baking also better maintained ω-3 PUFAs concentration than pre-roasting, resulting in higher (p < 0.05) concentration of α-linolenic (ALA, 18:3ω3), eicosapentaenoic (EPA, 20:5ω3), and docosahexaenoic (DHA, 22:6ω3) FAs as well as unsaturated FAs and total ω-3 FAs in DF surimi, DF FPI, and DF CPI. Pre-baking in combination with nutrification using ω-3 PUFAs improved nutritional value of DF foods, while causing minimal quality changes.
AtıfScopus3WoS3OpenAlex3
İncele - BildiriYalnız künye2024Exploring Triboelectric Properties in Sputtered Si(100)/SiO2/Cr/ZnO Thin Films - Ag/FEP Using Contact Speration Technique for Renewable Energy Harvesting
Yüzüak, Gizem Durak; Benhala, B.; Raihani, A.; Qbadou, M.
Currently, there is an ongoing inquiry into triboelectric nanogenerators (TENG), which use the triboelectric phenomenon to capture electrical energy from mechanical vibrations. The work aims to figure out the magnetron sputtered Cr/ZnO-based films on SiO2/Si(100) substrates with the construction of a Cr/ZnO-Ag/FEP tribo-based nanogenerator (TENG) and a specific emphasis on measuring TENG properties. The structural investigation of these films was conducted using X-ray diffraction (XRD) photoluminescence (PL), attenuated total reflectance fourier-transform infrared spectroscopy (AT-FTIR), and current - voltage (I-V) analysis in contact-separation mode (CSM). The Cr/ZnO-Ag/FEP TENG has a notable instantaneous maximum output voltage of around 63 V and a current density of 7 μA/cm2 when compared to other nanogenerators based on semiconductors, as determined by a comparative analysis. The results of this study provide useful information on the possible application of optimized magnetron sputtered Cr/ZnO-based films in triboelectric and energy harvesting systems, which might contribute to the progress of sustainable and renewable energy technologies.
- MakaleAçık Erişim2024Scopus SJRQ2Effects of Ga, Nb, V, Zr, and Cr on the crystal structures and thermal behavior of CuAlMn shape memory alloys
Özkul, İskender; Karaduman, Oktay; Canbay, Canan Aksu
CuAlMn alloys are cheaper and more promising alloy types compared to NiTi alloys. In this study, based on CuAlMn shape memory alloy, thermodynamic and structural characteristics of some new alloys containing four elements were investigated in detail. In this study, five new quaternary shape memory alloys, each containing a CuAlMn base alloy and a different fourth additive element (Ga, Nb, V, Zr, and Cr), were produced. The properties of the obtained alloys were characterized using a series of analysis methods such as X-ray diffraction (XRD), optical microscopy, differential scanning calorimetry (DSC), and differential thermal analysis (DTA). The results showed the effects of different elements on the crystal structures of the alloys and how different elements could change the thermal behavior of the alloys.
AtıfScopus4WoS3OpenAlex6İncele - MakaleAçık Erişim2024Scopus SJRQ2Is Cladophora fracta an efficient tool of accumulating critical raw materials from wastewater and there a potential health risk of use of algae as organic fertilizer?
Arslan Topal, E. Işıl; Öbek, Erdal; Topal, Murat
In this study investigation of accumulations of critical raw materials (cobalt (Co), antimony (Sb), vanadium (V), lanthanum (La) and tungsten (W)) from wastewater by using C. fracta were aimed. Besides, assessment of the potential health risks in terms of the use of organic fertilizer obtained from the macroalga to be harvested from the treatment were also aimed. Highest Co, Sb, V, La and W accumulations by algae in reactor were 125±6.2%, 201.25±10%, 318.18±15%, 357.97±18%, and 500±25%, respectively. When compared with control, Co, Sb, V, La and W in algae increased 2.25, 3.01, 4.18, 4.58, and 6 times, respectively. The algae was very high bioaccumulative for Co and La. Highest MPI was calculated as 3.94. Non-carcinogenic risk of CRMs according to different exposure types (ingestion, inhalation, and dermal) were calculated for man, woman and child. There is not any non-carcinogenic risk from the investigated exposure ways of algae as organic fertilizer.
AtıfScopus2WoS2OpenAlex2İncele - MakaleYalnız künye2024Scopus SJRQ2Synthesis and characterization of TiNbZrMo medium-entropy bio-composites: Microstructure, mechanical properties, and in vitro degradation
Say, Yakup
This study reports the synthesis and characterization of hydroxyapatite (HA)-based bio-composites reinforced with varying amounts (by weight, 1–15 wt.%) of bio-medium entropy alloy (BioMEA) for load-bearing implant applications. BioMEA powders consisting of Ti, Nb, Zr, and Mo were mechanically alloyed for 100 h and subsequently added to HA using powder metallurgy techniques. To show the effect of BioMEA, the microstructure, density, and mechanical tests have been conducted and the synthesized BioMEA was characterized by scanning electron microscope (SEM), x-ray diffractometer (XRD), and Fourier-transform infrared spectroscopy (FTIR) analysis. In addition, in vitro degradation behavior and bioactivity analyses of bio-composites have been conducted. XRD analysis revealed the formation of BioMEA after 20 h of mechanical alloying. The highest density value of 2.47 g/cm3 was found in 15 wt.% BioMEA-reinforced bio-composite. The addition of BioMEA reinforcement led to a significant increase in hardness and tensile strength values, with the highest values observed at 15 wt.% reinforcement. Compression tests demonstrated a significant increase in compressive strength and deformation capability of the bio-composites with the highest values observed at 15 wt.% BioMEA addition. The highest toughness of 7.68 kJ/m2 was measured in 10 wt.% MEA-reinforced bio-composites. The produced bio-composite materials have an elastic modulus between 3.5–5.5 GPa, which may provide a solution to the stress shielding problems caused by the high elastic modulus of metallic implant materials. The most severe degradation occurred in 15 wt.% MEA-reinforced bio-composites, and the effect of degradation caused a decrease in Ca and an increase in Ti-Ni-Zr-Mo in all bio-composites. These findings suggest that HA/BioMEA bio-composites have the potential to be developed as advanced biomaterials with moderate mechanical and biological properties for load-bearing implant applications.
AtıfScopus2WoS1OpenAlex3İncele - MakaleAçık Erişim2024Scopus SJRQ2Modeling the growth behavior of Salmonella spp. in grated carrots inoculated with different inoculum levels stored at various temperatures
Omac, Basri
The consumption of fresh and fresh-cut fruits and vegetables, such as carrots, has increased for the last decades for a healthy life and an adequate diet, but concerns regarding the microbial safety of them have been raised. The present study was conducted to develop predictive models for Salmonella spp. in grated carrots. The results showed that Salmonella spp. did not display growth at 5°C, but it grew in grated carrots at other temperatures (10, 15, 20, 25, and 37°C) for both inoculum levels. Also, the inoculum levels affected the growth of this pathogen in grated carrots when the storage temperatures ranged from 15 to 25°C. The theoretical minimum temperatures calculated using the Huang model were 3.48 and 5.79°C for inoculum levels of 101 and 102 CFU/g, respectively. The primary and secondary models performed well in terms of agreement between experimental and estimated values. Furthermore, compared to the Ratkowsky model, the theoretical minimum temperature was given a more reasonable value using the Huang model. The models developed in the present study will be a useful input for future quantitative microbial risk assessment to appraise the proliferation of Salmonella spp. in grated carrots throughout the production process, storage, and distribution.
AtıfScopus4WoS4OpenAlex5İncele - MakaleAçık Erişim2024Scopus SJRQ1The nation’s happiness, women’s altruism and the affective politics of self-blame: Generating a ‘mood of commitment’
Gülçiçek, Demet
This article contributes to the growing interest in affect and emotions in sociological research, with a specific focus on ‘mood’, developing the concept ‘mood of commitment’. It approaches political commitment as a mood, an affective lens, a dedication to a greater cause, asking how political commitments might be a low intensity affective relationship, and also a heightening, high intensity rhythm at the same time. I conceptualise ‘mood of commitment’ as an object of analysis that can be engaged to critically understand a wide range of political commitments. This article focuses on the case of Ottoman Muslim women’s movements in the early 20th century, amid the turmoil of nationalist movements and ‘modernisation’ processes. It firstly analyses objects of desires that are circulated to be persuasive in the political movements, and attunement of women’s movements with already existing nationalist movements. It secondly unpacks the kind of work involved in claiming to be in the ‘right’ mood of commitment, emphasising the production of hegemonic positions.
AtıfScopus2WoS2OpenAlex2İncele - MakaleAçık Erişim2024Scopus SJRQ2THE SPECTRUM AND PRINCIPAL FUNCTIONS OF A NONSELF-ADJOINT STURM-LIOUVILLE OPERATOR WITH DISCONTINUITY CONDITIONS
Kosar, N.P.; Akcay, O.
This paper deals with the nonself-adjoint Sturm-Liouville operator (or one-dimensional time-independent Schrödinger operator) with discontinuity conditions on the positive half line. In this study, the spectral singularities and the eigenvalues are investigated and it is proved that this problem has a finite number of spectral singularities and eigenvalues with finite multiplicities under two additional conditions. Moreover, we determine the principal functions with respect to the eigenvalues and the spectral singularities of this operator.
- MakaleYalnız künye2024Scopus SJRQ2Investigation of thermal, crystal and magnetic behavior of addition of Nd rare earth element effect on CuAlMn shape memory alloy
Kanca, Muhammed Sait
In this study, CuAlMn alloys, a popular Cu-based shape memory alloy, were chosen because they exhibit superior shape memory properties and improved ductility compared to other Cu-based SMAs. The rare earth element Nd (neodymium) was added to CuAlMn alloy at the specified atomic percentages in the composition Cu70-xAl24Mn6Ndx(x = 0,2,4,8) and their thermal behavior, crystal structure, surface morphology and magnetic properties were investigated after fabrication. As a result of the thermal analysis measurements, it was observed that for low Nd ratios, the austenite phase transformation initial temperature of the CuAlMn alloy was increased, while at high Nd ratios, a decrease in the shape memory property was detected. Martensitic phase and precipitate phase α phase were observed in the crystal structure properties of CuAlMn alloys without and with Nd doping. These results were also detected in surface morphology observations. In addition, the crystal size decreased from 135 to 105 nm with Nd doping. As a result of magnetic measurements, CuAlMn ternary shape memory alloy was found to be paramagnetic at room temperature. Magnetic susceptibility values of the alloys showing paramagnetic magnetic properties were calculated as 11.5 × 10–6, 12.5 × 10–6, 9.15 × 10–6 and 6.15 × 10–6 emu.Oe−1.g−1, respectively. According to these results, the magnetic susceptibility value decreased with increasing Nd ratio.
AtıfScopus3WoS3OpenAlex3İncele - MakaleAçık Erişim2024Scopus SJRQ4Ginkgo biloba L. extract and flunixin meglumine attenuate sepsis– associated liver injury, oxidative stress, inflammation and apoptosis in rats; [El extracto de Ginkgo biloba L. y la flunixina meglumina atenúan la lesión hepática, el estrés oxidativo, la inflamación y la apoptosis asociados a la sepsis en ratas]
Ak, Tuba Parlak; Gul, Burcu; Yaman, Mine; Seven, Ismail; Dagoglu, Gurdal; Gul, Huseyin Fatih
Lipopolysaccharide (LPS), known as a stimulant of inflammation, causes acute liver injury by inducing the production of inflammatory mediators and oxidative stress. The purpose of this study is to determine whether of a nonsteroidal anti–inflammatory drug (NSAID) Flunixin meglumine (FM) and herbal an medicine Ginkgo biloba L. extract (GBE) show antioxidative, anti–inflammatory or antiapoptotic effects in liver tissue in LPS–induced hepatotoxicity. Animals were separated to 6 groups as control, sepsis (1 mg·kg-1, 7th day single dose, intraperitoneal (ip)), sepsis + FM (1 mg·kg-1, 7th day single dose, ip + 2.2 mg·kg-1 day, ip), sepsis + GBE (1 mg·kg-1, 7th day single dose, ip + 50 mg·kg-1 day, gavage), FM and GBE and the study continued for 7 days. Liver tissues taken from rats sacrificed were analyzed biochemically, histologically and immunohistochemically. Accordingly, LPS caused liver function markers alteration, inflammation, oxidative stress, and apoptosis, as well as histopathological changes in liver tissue. However, it was observed that LPS–induced changes were regulated by FM and GBE application. FM and GBE was demonstrated to have antioxidant, antiinflammatory and anti–apoptotic properties in LPS– induced hepatotoxicity.
- MakaleAçık Erişim2024Scopus SJRQ2Genotypic diversity and antagonistic activities of enterococci isolated from pastırma
Ertekin, Özlem; Kaban, Güzin; Kaya, Mükerrem
The biodiversity of enterococci from pastırma (a traditional Turkish dry-cured meat product) by genotypic identification and the antagonistic activities of strains were investigated. Pastırma samples taken from 20 different small-scale factories were subjected to microbiological and physicochemical analysis. A hundred enterococci isolates were identified by 16S rRNA gene sequence analysis. To determine antagonistic activity of strains, Listeria monocytogenes and Staphylococcus aureus were used. The lactic acid bacteria and Micrococcus/Staphylococcus counts were ≥ 6 log cfu/g in 55% of the samples and 75% of the samples, respectively. Enterobacteriaceae was generally below the detectable level (< 2 log cfu/g). The enterococci count was higher than 6 log cfu/g in 30–35% of the samples, depending on the medium used. The enterococci isolates (100 isolates) were identified as E. faecium (80 strains), E. faecalis (19 strains) and E. hirae (1 strain) in genotypic identification. The nine E. faecium strains showed antagonistic activity against L. monocytogenes in the well diffusion test. In contrast, in the same antagonistic activity test, all of the strains had no antagonistic activity against S. aureus. Further studies could be planned to characterize E. faecium strains that show antagonistic activity against L. monocytogenes.
AtıfScopus2WoS2OpenAlex1İncele - MakaleAçık Erişim2024Scopus SJRQ1Ensemble Learning Framework for DDoS Detection in SDN-Based SCADA Systems
Oyucu, Saadin; Polat, Onur; Türkoğlu, Muammer; Polat, Hüseyin; Aksöz, Ahmet; Ağdaş, Mehmet Tevfik
Supervisory Control and Data Acquisition (SCADA) systems play a crucial role in overseeing and controlling renewable energy sources like solar, wind, hydro, and geothermal resources. Nevertheless, with the expansion of conventional SCADA network infrastructures, there arise significant challenges in managing and scaling due to increased size, complexity, and device diversity. Using Software Defined Networking (SDN) technology in traditional SCADA network infrastructure offers management, scaling and flexibility benefits. However, as the integration of SDN-based SCADA systems with modern technologies such as the Internet of Things, cloud computing, and big data analytics increases, cybersecurity becomes a major concern for these systems. Therefore, cyber-physical energy systems (CPES) should be considered together with all energy systems. One of the most dangerous types of cyber-attacks against SDN-based SCADA systems is Distributed Denial of Service (DDoS) attacks. DDoS attacks disrupt the management of energy resources, causing service interruptions and increasing operational costs. Therefore, the first step to protect against DDoS attacks in SDN-based SCADA systems is to develop an effective intrusion detection system. This paper proposes a Decision Tree-based Ensemble Learning technique to detect DDoS attacks in SDN-based SCADA systems by accurately distinguishing between normal and DDoS attack traffic. For training and testing the ensemble learning models, normal and DDoS attack traffic data are obtained over a specific simulated experimental network topology. Techniques based on feature selection and hyperparameter tuning are used to optimize the performance of the decision tree ensemble models. Experimental results show that feature selection, combination of different decision tree ensemble models, and hyperparameter tuning can lead to a more accurate machine learning model with better performance detecting DDoS attacks against SDN-based SCADA systems.
AtıfScopus36OpenAlex27İncele - MakaleAçık Erişim2024Scopus SJRQ1Delamination Magmatism in Eastern Anatolia: A Geochemical Perspective
Aktağ, Alican; Sayit, Kaan; Furman, Tanya; Peters, Bradley J.
The Sr-Nd-Hf-Pb isotope geochemistry of the Late Miocene Tunceli Volcanics suggests that they are the products of mixed asthenospheric and lithospheric mantle melts. The combined elemental and mineral chemistry data additionally indicate that a pyroxenite component of lithospheric origin is involved in their genesis. Calculations favor melting depths of ∼2 GPa for the Tunceli lavas, that is, deeper than the current lithosphere-asthenosphere boundary beneath Eastern Anatolia. Geochemical data suggest that during regional Neo-Tethyan subduction, dense (i.e., pyroxenite-bearing) domains formed by progressive melt intrusion into the lower lithosphere resulted in gravitational instabilities. This unstable density configuration eventually led to the foundering of the eastern Anatolian lithosphere in the Late Miocene, resulting in progressive melting of fusible pyroxenite-bearing domains at asthenospheric depths. We demonstrate that these pyroxenitic melts mixed with ambient asthenospheric melts and generated the Tunceli lavas.
AtıfScopus7OpenAlex9İncele - MakaleAçık Erişim2024Scopus SJRQ2Regional Climate Change and Drought Dynamics in Tunceli, Turkey: Insights from Drought Indices
Korkmaz, Meral; Kuriqi, Alban
Global warming and climate change are causing temperatures to rise, which is having a negative impact on water resources. Climate change is a worldwide problem that affects and will continue to affect the frequency and intensity of natural disasters in many regions of the world. Tunceli region in Turkey, which until 10 years ago was known as an environmentally friendly city with abundant water resources and frequent rainfall, is experiencing a decrease in precipitation during the snowy winter season. This situation has made the investigation of climate change impacts an important issue in the region. Therefore, effective climate change adaptation strategies need to be developed. To determine these strategies, in this study, we assessed long-term drought conditions using multiple drought indices such as Standardized Precipitation Index (SPI), Reconnaissance Drought Index (RDI), Normal Precipitation Index (PNI), and Aridity Index (AI). The SPI and RDI analyses were performed in annual reference periods on a time scale of 3, 6, 9, and 12 months using temperature, precipitation, and evaporation data. Consequently, the SPI and RDI results were compared, and both indices show similar behavior in dry, wet, and normal seasons. Nevertheless, RDI shows less variation between different time scales, which is an advantage over SPI and is probably due to the inclusion of potential evapotranspiration in RDI. The variations in PNI between humid and dry sub-humid categorizations throughout the years, combined with the AI results, indicate that the Tunceli region predominantly experiences a climate ranging from dry sub-humid to semi-arid. This study could help decision-makers take effective measures to become more resilient to climate change in temperate climate regions and take important steps toward sustainable water resources management.
AtıfScopus17WoS15OpenAlex20İncele - MakaleYalnız künye2024Scopus SJRQ2Mechanical and thermal properties of short banana fiber reinforced polyoxymethylene composite materials dependent on alkali treatment
Doğan, Akar; Güneş, Çağdaş
The present study aimed to develop a recyclable composite material based on a natural product, namely banana fiber, instead of synthetic reinforcement elements such as glass fiber or carbon fiber in thermoplastic matrix composites employed in many aspects of daily life. Polyoxymethylene (POM) thermoplastic was used as the matrix material. 3 %, 6 %, and 9 % by weight short natural banana fiber was used as reinforcement. Furthermore, the study improved the mechanical and thermal properties of the composite material with chemical improvements based on alkali treatment of banana fiber. Banana fiber and POM was initially mixed mechanically and then extruded at temperatures between 170 and 190 °C to obtain a homogeneous mixture. The mixture obtained by extrusion was initially cooled in the cooling pool and then passed through the crusher to obtain granules. These granules were pressed in plastic injection molds to obtain standard test samples. The ratio of reinforcement material and the variations in mechanical and thermal properties of the composites induced by the alkali treatment are presented in figures and tables. Furthermore, the changes in cross-sectional material images were examined with electron microscopy scans. The tensile and flexural strength of the material improved with alkali treatment.
AtıfScopus21WoS19OpenAlex20İncele