Sürdürülebilir Kalkınma Amaçları

Yazarlar

  • MakaleAçık Erişim2021Scopus SJRQ4
    Automatic Classification of COVID-19 using CT-Scan Images

    Reis, Hatice Catal

    Medicine and engineering sciences have been working in close contact for common purposes. Machine learning algorithms are used in the medical field for early diagnosis prediction. The major aim of this study is to evaluate machine learning algorithms and deep learning algorithms using computed tomography scan (CT-scan) images for automated detection of the coronavirus disease 2019 (COVID-19) patients. We obtained seven hundred and fifty-seven (757) CT-scan images from a public platform. We applied four automated traditional classification methods to predict COVID-19 using deep learning and machine learning. These algorithms are SVM, AdaBoost, NASNetMobile, and InceptionV3. Comparative analyses are presented among the four models by considering metric performance factors to find the best model. The results show that the InceptionV3 model achieves better performance in terms of accuracy, precision, recall, Cohen’s kappa, F1-score, root mean squared error (RMSE), and receiver operating characteristic-area under the curve (ROC-AUC), in comparison with the other Covid-19 classifiers. Accordingly, the InceptionV3 approach is recommended for the automatic diagnosis of Covid-19 and assessments. This research can present a second point of view to medical experts and it can save time for researchers as the performance of standard machine learning methods in detecting COVID-19 is evaluated.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus1WoS1OpenAlex1
    ScopusWeb of Scienceİncele
  • BildiriYalnız künye2021
    Stability estimates for a third order of accuracy difference scheme elliptic overdetermined multi-point problem

    Ashyralyyev, Charyyar; Akyuz, Gulzipa; Cakalli, H.; Kocinac, L.D.R.; Ashyralyev, A.; Harte, R.; Dik, M.; Canak, I.; Kandemir, H.S.; Tez, M.

    In this work, we discuss a third order of accuracy difference scheme for approximate solution of the elliptic overdetermined multi-point problem in the Hilbert space. Functional operator approach is used to study existence and uniqueness of solution of difference problem. Stability, almost coercive stability and coercive stability estimates for solution of difference scheme are established.

  • MakaleAçık Erişim2021Scopus SJRQ4
    Evaluation of added sugar and sugar-sweetened beverage consumption by university students

    Meric, Çağdaş Salih; Ayhan, Nurcan Yabanci; Yilmaz, Hacı Ömer

    Today, increased intake of sugar and sugar-sweetened beverages is seen as an important factor in the growing prevalence of chronic diseases, such as obesity, obesity-related diabetes, and coronary heart diseases. This study involved 214 Ankara University students from the Department of Nutrition and Dietetics, which was intended to evaluate the consumption of sugar and sugar-sweetened beverages. The frequency of student consumption of beverages and the quantities and amounts of sugar taken with beverages were questioned. The average total amount of sugar added to drinks by the students was 4.69 ± 6.35 gram, while the average total amount of sugar taken with sugar-sweetened beverages was 11.34 ± 15.32 gram. Female students relative to male students, students in grade 4 compared to grades 2 and 3, and students who had daily breakfast compared to those who did not had lower average sugar consumption (p-value < 0.05). As class grades increase, the amount of sugar added to beverages and fruit juice and sweetened soft drinks and carbonated beverages decreased (p-value < 0.05). The consumption of herbal teas and dietary beverages increased and the eating habits of students generally changed positively (p-value > 0.05). It is important to educate university students about the reduction in sugar intake and sugar-containing food in order to avoid many chronic diseases that may be seen in older ages.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus6WoS5OpenAlex7
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  • MakaleAçık Erişim2021Scopus SJRQ2
    Investigation of class 1 integrons with antibiotic resistance genes in multidrug-resistant acinetobacter baumannii strains and determination of plant extract effects on multidrug-resistant isolates

    Saral, Ayşegül; Cinemre, Sedanur; Okumuş, Funda; Akar, Zeynep; Çiçek, Ayşegül Çopur; Düzgün, Azer Özad

    This study aimed to investigate the presence of resistance genes in multidrug-resistant A. baumannii isolates as well as to determine the antibacterial activity of selected plant extracts against isolates. 41 strains were isolated from various clinical samples. PCR tests were performed using the primers. Methanol was used as solvent for the preparation of the plant extracts. MIC values of the plant extracts were determined by the broth microdilution method. The blaOXA-23, blaCTX-M-1, blaCTX-M-2, blaGES genes and Class 1 integrons were detected in five isolated strains. The lowest MIC value (2.25 mg/mL) was determined for the Echinacea purpurea extract, while the highest MIC value (50 mg/mL) was determined for the Morus alba extract. Determination of the antibacterial effect of plants extracts used in the study against A. baumannii isolates shows the importance of screening the antibacterial activity of plants in the fight against antibiotic resistance.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus1WoS1OpenAlex3
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  • MakaleYalnız künye2021Scopus SJRQ2
    Crustal Contamination of Tertiary Volcanic Rocks: Evidence from K, U, Th and Radiogenic Heat Production Data in Eastern Pontides (NE Turkey)

    Maden, Nafiz; Akaryalı, Enver; Aydınçakır, Emre

    Herein, we present new 238U, 232Th, and 40K radionuclide concentrations, density and radiogenic heat production (RHP) data on the Tertiary volcanic rocks outcropping in Borçka, Gumushane and Trabzon regions within the Eastern Pontide Orogenic Belt (EPOB). The mean K values for Trabzon, Borçka and Gümüşhane regions were 2.19 ± 0.87%, 0.90 ± 0.70% and 0.59 ± 0.25%, respectively, the mean U values for Trabzon, Borçka and Gümüşhane regions were 2.12 ± 0.76 ppm and 1.29 ± 0.68 ppm and 0.90 ± 0.32 ppm, and the average Th values were calculated as 6.54 ± 2.32 ppm, 2.49 ± 1.93 ppm and 1.33 ± 0.60 ppm for Trabzon, Borçka and Gümüşhane regions, respectively. The average Th/U values are 3.38 ± 1.48 for the Trabzon region, 2.01 ± 1.22 for the Borçka region, and 1.69 ± 1.09 for the Gümüşhane region. Average U/Th values were calculated as 0.35 ± 0.14, 0.71 ± 0.52 and 0.89 ± 0.72 for the Trabzon, Borçka and Gümüşhane regions, respectively. The RHP values were determined as 1.16 ± 0.35 μW m - 3, 0.58 ± 0.33 μW m - 3 and 0.37 ± 0.10 μW m - 3 for Trabzon, Borçka and Gümüşhane regions, respectively. The Tertiary aged rocks in the EPOB that we have examined within this study scope have been derived from an enriched mantle, previously metasomatized by fluids derived from subducted slab. The parental magma of Eocene basaltic rocks was contaminated with crustal material during the ascension of the magma through the crust or in the shallow-level crustal magma chambers.

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  • MakaleAçık Erişim2021Scopus SJRQ4
    Evaluation of Load-Transfer Efficiency of Steel Mesh Reinforced Contraction Joints in Concrete Pavement: Accelerated Pavement Test and FE Analysis

    Celik, Muhammet; Seferoglu, Mehmet Tevfik; Akpinar, Muhammet Vefa; Nasery, Mohammad Manzoor; Seferoglu, Aysegul Gunes

    Transverse contraction joints are by far the most common type of joint in jointed plain concrete pavements. Early loading of contraction joints can create a weakened vertical plane and later grow as a full-depth crack. In this study, load transfer efficiency (LTE) of steel mesh reinforced transverse contraction joints were studied at accelerated pavement tests (APT). 3D finite element (FE) model of jointed plain concrete pavement (JPCP) was developed to study deflections and crack propagation in just under the joint of the concrete pavement. The APT tests were focused on the LTE values before and after the crack initiation under the contraction joint region. Experiments were performed on three slabs in which two of these slabs were prepared without reinforcement and one of them was reinforced with steel mesh. Data generated by APT was used for verification of crack propagation modeling in the finite element analysis. Steel mesh reinforced slab gave the lowest vertical deflections (51μm) and highest LTE (91.56%). The LTE value in the reinforced slab after 25,000 passes was 13.63% higher than the average of unreinforced slabs. The findings suggest that the load transfer efficiency was found to be a complex parameter and should be interpreted together with average displacement values when contraction joints are evaluated at early traffic loadings.

    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    AtıfScopus3WoS2OpenAlex2TR Dizin1
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  • MakaleYalnız künye2021Scopus SJRQ2
    Design of series tuned mass dampers for seismic control of structures using simulated annealing algorithm

    Araz, Onur; Kahya, Volkan

    The effectiveness of the series tuned mass dampers (STMDs) in reducing the dynamic vibrations of the structures under the ground motion is investigated, and their optimum parameters are obtained based on the simulated annealing (SA) optimization. The STMD is one of the most well-known passive control devices which consists of two TMD units arranged in series. However, only a few studies are available on the control performance and optimum parameters of the STMDs for structural systems subjected to ground motion. Thus, the goal of this study is to carry out a thorough optimization analysis based on the SA algorithm for the structures equipped with an STMD under the effect of ground motion. The objective function is selected as the reduction of the displacement response of the structure. It is proved that the optimum STMD has better effectiveness than the optimum TMD in suppressing the maximum story displacement of the structure. Further, the effect of the frequency shift on the effectiveness of the optimally designed STMD is investigated.

    AtıfScopus38WoS32OpenAlex37
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  • MakaleYalnız künye2021Scopus SJRQ2
    Investigating the historical development of accuracy and precision of Galileo by means of relative GNSS analysis technique

    Yalvac, Sefa

    Galileo navigation system has significantly expanded satellite constellation over the last few years and now serves with 22 satellites in three orbital planes. The development of the Galileo is not only limited to the number of satellites in the space segment, but also the quality of the IGS MGEX products produced by different Analysis Centers has increased gradually and brought up the topic of investigation of the accuracy and precision of the Galileo-only positioning. However, almost all of the studies on Galileo-only positioning in the literature have been performed with Precise Point Positioning method and comprehensive studies with the relative positioning technique are quite a few. In this study, the development of the accuracy and precision of the Galileo from 2016 to the end of 2019 (4 years) has been investigated for the first time by means of relative positioning technique. For this purpose, data of eight GNSS stations selected from the IGS MGEX network were obtained and analyzed with GAMIT/GLOBK software as GPS-only and Galileo-only, separately. Using the daily solutions obtained from both navigation systems, time series were produced and the differences between them were compared in order to reveal the Galileo accuracy. According to the results, the accuracy of the Galileo was variable during the experiment and it could be examined in three periods. The averages of 3D positioning error in the first period (2016-2017) is 14.92 mm and improved by 56%, and decreased to 6.55 mm in the second period (2017-2018), and then improvement at 23% in the third period (2018 to the end of 2019) and decrescent to level of 5.13 mm on average for all stations. Similarly, standard deviations obtained from Galileo increased during the experiment and during the 3rd period it was closed to a few mm with GPS. It was concluded that the accuracy and precision of the Galileo showed parallel development and the development was directly related to the number of satellites in the Galileo constellation, and as a result, nowadays, Galileo-derived coordinates are close to the coordinates obtained from the GPS by a few mm.

    AtıfScopus10WoS10
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  • MakaleAçık Erişim2021Scopus SJRQ1
    Analysis of salt lake volume dynamics using sentinel-1 based SBAS measurements: A case study of lake Tuz, Turkey

    Bilgilioğlu, Burhan Baha; Erten, Esra; Musaoğlu, Nebiye

    As one of the largest hypersaline lakes, Lake Tuz, located in the middle of Turkey, is a key waterbird habitat and is classified as a Special Environmental Protection Area in the country. It is a dynamic lake, highly affected by evaporation due to its wide expanse and shallowness (water depth <40 cm), in addition to being externally exploited by salt companies. Monitoring the dynamics of its changes in volume, which cause ecological problems, is required to protect its saline lake functions. In this context, a spatially homogeneous distributed gauge could be critical for monitoring and rapid response; however, the number of gauge stations and their vicinity is insufficient for the entire lake. The present study focuses on assessing the feasibility of a time-series interferometric technique, namely the small baseline subset (SBAS), for monitoring volume dynamics, based on freely available Sentinel-1 data. A levelling observation was also performed to quantify the accuracy of the SBAS results. Regression analysis between water levels, which is one of the most important volume dynamics, derived by SBAS and levelling in February, April, July and October was 67%, 80%, 84%, and 95% respectively, for correlation in the range of 10–40 cm in water level, and was in line with levelling. Salt lake components such as water, vegetation, moist soil, dry soil, and salt, were also classified with Sentinel-2 multispectral images over time to understand the reliability of the SBAS measurements based on interferometric coherence over different surface types. The findings indicate that the SBAS method with Sentinel-1 is a good alternative for measuring lake volume dynamics, including the monitoring of water level and salt movement, especially for the dry season. Even though the number of coherent, measurable, samples (excluding water) decrease during the wet season, there are always sufficient coherent samples (>0.45) over the lake.

    • SDG 6 · Temiz Su ve Sanitasyon
    AtıfScopus4WoS5OpenAlex6
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  • MakaleYalnız künye2021Scopus SJRQ2
    A copula approach for sea level anomaly prediction: a case study for the Black Sea

    Yavuzdoğan, Ahmet; Tanır Kayıkçı, Emine

    Forecasting future sea levels is of great importance in terms of the conservation of coastal areas, monitoring and forecasting coastal ecosystems, and the maintenance and planning of coastal structures. In addition, highly accurate sea level forecasts allow adequate water management policies and coastal infrastructures to be developed. Today, many methods, such as harmonic analyses, artificial neural networks and support vector machines, are used to predict sea level anomalies. In this study, a novel approach based on Copula functions is presented for the prediction of sea level anomalies. The primary purpose of this study is to examine the applicability and capability of Copula-based prediction models in predicting short-term variations in the sea level. The minimum 95% correlations and minimum 22 mm RMSE values in sea level anomaly predictions during the testing period indicate that the Copula approach can be a powerful tool in the prediction of sea level anomalies.

    • SDG 13 · İklim Eylemi
    AtıfScopus12WoS10OpenAlex10
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  • MakaleAçık Erişim2021Scopus SJRQ1
    Investigation of the Effect of the Dataset Size and Type in the Earthquake-Triggered Landslides Mapping: A Case Study for the 2018 Hokkaido Iburu Landslides

    Comert, Resul

    Rapid mapping of landslides that occur after an earthquake is important for rapid crisis management. In this study, experimental research was conducted on the size of the model area and the data types used in developing classifiers for the supervised classification approaches used in rapid landslide mapping. The Hokkaido Iburu earthquake zone that occurred on September 6, 2018, was selected as the study area. PlanetScope pre-event and post-event images and ALOS-PALSAR Digital Elevation Model (DEM) were used in the analysis processes. In this context, five model areas with different sizes and one test area were determined. Object-based image analysis (OBIA) was used as a landslide mapping approach. Random Forest classifier, which is a supervised classification algorithm, was performed in the mapping of image objects produced by the segmentation stage of OBIA. Two different data sets were created for landslide mapping: change-based dataset and post-event dataset. The change-based dataset is generated from change data such as the difference of normalized difference vegetation index (δNDVI), change detection Image (CDI), princiable component analysis (PCA), and Independent component analysis (ICA) which are used in change detection applications. The post-event dataset was created from data generated from post-event image bands. When the obtained results were examined, higher accuracy results were obtained with the post-event dataset. Increasing the size of the model area, in other words, increasing the training data slightly increases the accuracy of landslide mapping. However, a model area that represents the region to be mapped in small sizes to make rapid decisions provides a 94% F-measure accuracy for earthquake-triggered landslide detection.

    • SDG 11 · Sürdürülebilir Şehirler ve Topluluklar
    AtıfScopus13WoS12OpenAlex13
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  • MakaleYalnız künye2021Scopus SJRQ2
    Neuro sliding mode control of quadrotor UAVs carrying suspended payload

    Bingöl, Ö.; Güzey, H.M.

    In this paper, a neuro-sliding mode controller (SMC) has been designed for a quadrotor transporting a suspended payload. SMCs are very efficient under uncertain conditions. However, if the uncertain dynamics change over time, SMC gains need to be updated to maintain the tracking performance. This study proposes a neuro-SMC to control a quadrotor UAV carrying a suspended payload in the existence of time-varying uncertain dynamics. Once the accuracy of the proposed controller is demonstrated theoretically using the Lyapunov stability criterion, the effectiveness of the proposed controller is shown in simulation, which confirms the theoretical claims.

    AtıfScopus26WoS22OpenAlex28
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  • MakaleAçık Erişim2021
    Phytic acid content and in-vitro digestibility of several cereal and legume types treated with different processes

    Bektaş, Müberra; Ertop, Müge Hendek

    Introduction. The present study aims to determine the relationship between phytic acid (PA) content/digestibility rate of the grains, which are widely consumed in daily diet, and the methods often used in preparing food for consumption. Materials and methods. In this study, the dephytinization effect of soaking (for 12 h), boiling (at 100 °C for 1 h), autoclaving (at 121°C for 15 min), fermentation (at 25-27 ℃), and germination processes on several grains were studied. PA contents, Mineral Digestibility (MD, %), and Protein Digestibility (PD, %) were determined, and their effects comparatively evaluated before and after processes. Results and discussion. There were decreases in PA contents in legumes and cereals for all the methods applied. Fermentation (<800 mg/100 g) of the flour and germination for the other samples (<700 mg/100 g) were found to yield more effective results to PA degradation. Between 20-70% reduction by fermentation and 50-80% reduction by germination of PA contents in the samples were found. Moreover, MD level in cereals, which was especially low before germination, increased up to 2 times after the germination. PD, %, was found to increase with the effect of the processes, except for boiling and soaking. Especially germination process was more effective in tems of PD. Increasing rate of PD for ten bean samples was up to 200%. Wheras the PA contents in the cereal flour samples after their spontaneous fermentation were decreased, their digestibility values were increased statistically (p<0.05). Conclusions. All processes applied such as soaking, fermentation, or heat treatments, which are widely used to preparation of the grains, provide an advantage in dephytinization at different rate. Combined use of techniques such as soaking, and boiling which are used in the preparation of various cereal and legume products for consumption, is also be effective in terms of nutritional quality and their combinations were proposed.

    • SDG 2 · Açlığa Son
    AtıfScopus7WoS5OpenAlex5
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  • MakaleYalnız künye2021Scopus SJRQ1
    Determination of START triage skill and knowledge levels of Prehospital Emergency Medical Staff: A cross sectional study

    Aslan, Ramazan; Şahinöz, Saime; Şahinöz, Turgut

    Background: Emergency medical staff working in pre-hospital (PH-staff) may encounter mass casualty incident (MCI) events. In these events these medical personnel should perform triage. The objective of this study is to determine the skill and knowledge levels of PH-staff about Simple Triage and Rapid Treatment (START) triage. Methods: With this cross-sectional, observational study we analyzed data from 127 PH-staff. Data was collected with the survey tool (response rate = 74.7%). Kruskal-Wallis H Test, Mann-Whitney U Test, and Spearman's Correlation analyzes were used in the data analysis by means of SPSS Software. Results: Of the participants, 63% were men, the median age was 24 years, 88 PH-staff (69.3%) intervened in MCI events, and 37 PH-staff (29.1%) applied START triage. The skill score was 60% and the knowledge score was 72.5%. There was a weak positive correlation between knowledge and skill scores (r = 0.337, p < 0.01). The knowledge level of the emergency medical technicians (EMTs) and paramedics was higher than those from the other professions. Conclusions: The triage knowledge and skill levels of the PH-staff were not low contrary to the expectations. The triage knowledge and skill levels of professions that did not have pre-hospital training such as paramedics and EMTs were low.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus7WoS6OpenAlex15
    ScopusWeb of SciencePubMedİncele
  • MakaleYalnız künye2021Scopus SJRQ2
    Exopolysaccharide of Anoxybacillus pushchinoensis G11 has antitumor and antibiofilm activities

    Genc, Berna; Taskin, Mesut; Adiguzel, Ahmet

    Exopolysaccharides (EPS/EPSs) possess several various applications in the food and pharmaceutical industries. This study was performed to investigate the biological (antibiofilm and antitumor), rheological (temperature, shear rate, and density) and chemical (solubility, carbohydrate and protein content, composition, molecular weight, functional group analysis, thermal analysis, X-ray diffraction pattern and scanning electron microscopy) properties of the EPS, which was purified from the locally isolated thermophilic bacterium Anoxybacillus pushchinoensis G11 (MN720646). EPS was found to have antibiofilm and antitumor [lung (A-549) and colon (Caco-2 and HT-29) cancer] activities. The viscosity of EPS showing Newtonian flow was temperature dependent. As chemical properties, the EPS was found to be a heteropolysaccharide containing arabinose (57%), fructose (26%), glucose (12%), and galactose (5%). EPS contained 93% carbohydrates and 1.08% protein. The molecular weight of EPS was determined as 75.5 kDa. The FTIR analysis confirmed the presence of sulfate ester (band at 1217 cm−1), an indication of the antitumor effect. The EPS was semi-crystalline. It could maintain 36% of its weight at 800 °C and crystallization and melting temperatures were 221 and 255.6 °C. This is the first report on the EPS production potential and the biological activity of A. pushchinoensis.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus22WoS21OpenAlex25
    ScopusWeb of SciencePubMedİncele
  • MakaleYayıncıda açık erişim2021Scopus SJRQ3
    A contribution to the biogeography and taxonomy of two anatolian mountain brook newts, neurergus barani and n. Strauchii (amphibia: Salamandridae) using ecological niche modeling

    Kurnaz, Muammer; Şahin, Mehmet Kürşat

    The Anatolian newt, Neurergus strauchii, is an endemic Anatolian species. Until recently, N. strauchii was represented by three subspecies. It has been discussed within a recent phylogenetic study in which the subspecies N. s. barani is recommended to be evaluated as a cryptic but distinct species. To address this subject, we aimed to discuss the niche differentiation between N. barani and N. strauchii using geographical and bioclimatic aspects. All georeferenced data of N. barani and N. strauchii were used to estimate the potential distributions of these species in the Anatolian Peninsula. To evaluate their ecological niche differentiation, point-based analysis and niche similarity tests were done. Ecological niche modeling outcomes demonstrated a significant niche differentiation between N. barani and N. strauchii. Moreover, since these species are distributed in the east and west of the Euphrates Basin, this river might be considered as a geographic barrier that can cause isolation for these species. Lastly, we demonstrated their potential distributions for future with several scenarios. Our findings strengthened the results of the recent phylogenetic study and indicated the necessity of handling “barani” taxa at the species level. Moreover, these results contribute, as a piece of evidence, to the biodiversity of Anatolia where another endemic species lives.

    • SDG 15 · Karasal Yaşam
    AtıfScopus12WoS12OpenAlex7
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  • MakaleYalnız künye2021Scopus SJRQ2
    Effect of working pressure and post-annealing on structural, optical and electrical properties of p-type NiO thin films produced by RF magnetron sputtering technique

    Şenaslan, Fatih; Taşdemir, Muharrem; Çelik, Ayhan

    Nickel oxide (NiO) films were deposited on glass and silicon substrates using a Ni target by radio-frequency (RF) sputtering at various working pressure ranging from 5 to 20 mTorr. The films were annealed for 2 h at 400 °C in the air ambient. The effect of working pressure on structural, optical and electrical properties of NiO films was investigated in detail. The deposition rate of the films gradually increased with decreasing working pressure. The X-ray diffraction (XRD) presented that the crystal quality and the average crystallite size of annealed films increased with decreasing working pressure. The X-ray photoelectron spectroscopy (XPS) confirmed the presence of Ni2+ and Ni3+ ions along with the main peak and satellite peaks in the NiO films. Raman spectroscopy exhibited the one-phonon and two-phonon vibrations modes corresponding to Ni–O bond. UV–Visible analyses showed that annealed NiO thin films have higher transmittance than deposited ones. The band gap of the films increased from 3.33 to 3.52 eV with decreasing working pressure and further increased after the annealing process. The electrical properties were affected by the varying crystallinity and lattice defects depending on the deposition condition. All annealed NiO films exhibited p-type conductivity. The lowest resistivity (4.2 Ω.cm) was obtained from the annealed film after deposition at 5 mTorr.

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  • MakaleYalnız künye2021Scopus SJRQ4
    Relationship between certain biochemical parameters and maximal aerobic speed of elite soccer players

    Cebi, Mehmet; Ceviker, Abdulkerim; Ozlu, Kurtulus; Elioz, Murat; Yamak, Bade; Kusan, Osman; Agaoglu, Seydi Ahmet; Dogan, Erol; Ceylan, Levent

    Study Objectives: In this study, it was aimed to evaluate the relationship between vitamin D and lipid profiles of athletes playing football professionally during the season and some metabolic parameters and maximal rate. Methods: 52 male elite soccer players performing in Super League, TFF 2nd League, and TFF 3rd League whose mean age 22.86±3.55 years, participated in our study. The sport age of the soccer players was 12.2±1.70 years. The participants attended in at least five 80-minute training periods and performed at least one official competition weekly (through 11 months). In November, blood samplings of the athletes and other parameters were obtained between 09:00 and 10:00 a. m. leading a 12-hour fasting period. The Maximal Aerobic Speed (MAS) measurement developed by Buchheit (2008) to evaluate aerobic power and capacity was used to carry out the study. In order to determine the relationship between the variables of individuals, Pearson Correlation Test was used as the data showed normal distribution. Results: Albumin, Alp, Alt, Ast, B12 vitamin, Ca, Phosphorus, Creatinine, Mg, Free T3, Sodium, Tsh, Ferritin, Folic Acid, Potassium Triglyceride, Glucose, Total Cholesterol, and Free T4 values were found within normal limits. It can be said that athletes had low vitamin D values. It was observed that the participants had low LDL cholesterol values. Variables don’t have any significant effects on running time, peak velocity, true vift and VO2max of biochemical parameters (p>0,05). Conclusion: As a result, it can be concluded that despite the positive relationship between the maximal aerobic velocity test parameters of the footballers and their pre-test biochemical results, it wasn’t statistically a meaningful relationship.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus2WoS3OpenAlex1
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  • MakaleYalnız künye2021Scopus SJRQ2
    Effects of graphene oxide addition on wear behaviour of composite coatings fabricated by plasma electrolytic oxidation (PEO) on AZ91 magnesium alloy

    Kucukosman, Rıdvan; Sukuroglu, Ebru Emine; Totik, Yasar; Sukuroglu, Suleyman

    Graphene oxide (GO) integrated composite coatings were deposited on AZ91 magnesium alloys by the PEO (Plasma Electrolytic Oxidation) and the treatment which has a post-PEO hydrothermal process. For the first group samples, PEO was performed in the silicate/phosphate-based electrolyte including 5–10 µm in size the GO particles synthesized using the Tour Method. For the second group samples, after PEO treatment, the post-PEO hydrothermal process was carried out in the oven in the GO-distilled water mixture containing GO produced with the same protocol. The effects of GO on wear behavior, structural and morphological features of composite coatings were examined with a pin-on-disc tribometer, X-ray diffraction (XRD), scanning electron microscopy (SEM) and Raman spectroscopy, respectively. The results showed that the addition of GO improved significantly the adhesion to the substrate material of composite coatings, increased the coating thickness and hardness. Post-PEO hydrothermal process resulted in the formation of partial a thin solid lubricant GO film on the surface of composite coatings and thus exhibited the best wear and friction resistance.

    AtıfScopus26WoS24OpenAlex24
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  • MakaleAçık Erişim2021Scopus SJRQ3
    Wong-Zakai Method for Stochastic Differential Equations in Engineering

    Sengul, Suleyman; Bekiryazici, Zafer; Merdan, Mehmet

    In this paper, Wong-Zakai approximation methods are presented for some stochastic differential equations in engineering sciences. Wong-Zakai approximate solutions of the equations are analyzed and the numerical results are compared with results from popular approximation schemes for stochastic differential equations such as Euler-Maruyama and Milstein methods. Several differential equations from engineering problems containing stochastic noise are investigated as numerical examples. Results show that Wong-Zakai method is a reliable tool for studying stochastic differential equations and can be used as an alternative for the known approximation techniques for stochastic models.

    AtıfScopus4WoS4OpenAlex5
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