Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Uzun, Sevda(64)
- Merdan, Mehmet(47)
- Baltaci, Cemalettin(35)
- Kulakaç, Nurşen(28)
- Duran, Celal(27)
- Ozdes, Duygu(24)
- Turan, Ibrahim(24)
- Demir, Selim(23)
- Türkkan, Tuğba(22)
- Bayrakdaroglu, Serdar(21)
- Topal, Fevzi(21)
- Öztürk, Serkan(21)
- Ürkek, Bayram(21)
- Gücer, Mehmet Ali(20)
- Akar, Zeynep(19)
- Kaygusuz, Abdullah(19)
- Topal, Meryem(19)
- Anaç, Halil(18)
- Aydin, Aydanur(18)
- Batan, Nevzat(18)
- Erata, Hüseyin(18)
- Tuncer, Metin(18)
- Akyürek, Suat(17)
- Baltacı, Cemalettin(17)
- Karimullah, Suud Sarim(17)
- Acet, Tuba(16)
- Akar, Bülent(16)
- Ashyralyyev, Charyyar(16)
- Düzgün, Azer Özad(16)
- Hintistan, Sevilay(16)
- Yılmaz, Coşkun(16)
- Aliyazicioglu, Yuksel(15)
- Kaya, Hacer(15)
- Kurnaz, Muammer(15)
- Kurt, Kemal(15)
- Ozden, Talat(15)
- Yilmaz, Coskun(15)
- Yuksel, Ferhat(15)
- Yücel, Cem(15)
- Öz, Mehmet(15)
Yayınlar
- MakaleAçık Erişim2021Scopus SJRQ4Automatic 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.
AtıfScopus1WoS1OpenAlex1
İncele - MakaleAçık Erişim2021Scopus SJRQ4Evaluation 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.
AtıfScopus6WoS5OpenAlex7İncele - MakaleAçık Erişim2021Scopus SJRQ2Investigation 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.
AtıfScopus1WoS1OpenAlex3İncele - MakaleAçık Erişim2021Scopus SJRQ4Evaluation 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.
AtıfScopus3WoS2OpenAlex2TR Dizin1
İncele - MakaleAçık Erişim2021Temporal monitoring of land use/land cover change in Kahramanmaraş city center
Aliyazicioglu, Kubra; Beker, Fatmanur; Topaloglu, Raziye Hale; Bilgilioglu, Burhan Baha; Comert, Resul
Irregular urbanization causes problems such as decrease in fertile agricultural areas, irregular industrialization and urbanization. To provide a healthier life opportunity for future generations without disturbing nature, it is essential to determine the temporal changes in land use and to make land management plans accordingly. In this study, land use/land cover (LULC) change occurred in Kahramanmaras province within 30 years was investigated by remote sensing and integration of Geographic Information Systems. Landsat satellite images of 1988-1998-2008-2018 were obtained for the production of LULC maps. Each image was classified according to supervised classification approach using the support vector machines (SVMs) algorithms. The confusion matrix was created for each year to examine the accuracy of the LULC maps. The overall accuracy of the thematic maps was obtained as 91.76%, 93.56%, 86.89% and 88.29%, respectively. Also, Kappa values of thematic maps for each year were obtained as 0.88, 0.91, 0.81 and 0.84, respectively. When the results were examined, the development of industry in the city area and the construction of the airport contributed to the development of the social and economic structure of the city. The increase in the number of housing in the related regions has led to an increase in the amount of urban areas and a decrease in agricultural areas.
AtıfScopus9OpenAlex13TR Dizin4İncele - BildiriAçık Erişim2021GIS-BASED OPTIMUM SITE SELECTION for SOLAR ELECTRIC VEHICLE CHARGING STATION: ANKARA-ISTANBUL HIGHWAY CASE
Hisoglu, Seyit; Comert, R.; Karas, I.R.; Ben Ahmed, M.; Boudhir, A.A.; Ane, B.K.
Energy sources are divided into renewable and non-renewable sources. It can be seen that non-renewable energy resources are not adequately meeting the increased demands of worldwide technological developments, increasing population, and global consumption. Therefore, the demand for renewable resources is increasing day by day. When it comes to the use of non-renewable carbon-based fossil fuels, one of the first areas that come to mind is undoubtedly the Automotive sector. Today, it is realized that one of the main reasons for the lack of electric motor cars compared to petroleum fuelled cars, is the scarcity of electric vehicle charging stations and the difficulty of their accessibility. In this study; an analysis of solar-powered electric charging stations site selection was carried out for electric vehicles. The Ankara-Istanbul highway, which has a high traffic density, was chosen as the sample route for the study. Within the scope of the study, the areas where stations can be installed on the highway were carried out using the Multi-Criteria Decision Making Method with the help of Geographic Information System. Solar radiation, slope, aspect, land use/land cover, traffic volume and proximity to the road, criteria of the route, and site selection analysis were determined as input data. The maps of the determined criteria were arranged according to the study area and prepared for analysis. The criteria maps obtained were reclassified according to the above-mentioned criteria and scoring system. After the reclassification process, the weighting of each criteria which affect the analysis was determined by the researched literature and an overlapping process was carried out. According to the results map produced as a result of the overlay analysis, the appropriate area has been determined for the electric charging stations working with solar energy. On the defined route within the scope of the study, a proposal has been made for a total of 13 stations, 8 in Ankara, 3 in Bolu, 1 in Kocaeli, and 1 in Istanbul. This study, it is aimed to encourage automobile users to make greater use of electric motor vehicles, which would be a more environmentally friendly and sustainable choice, and ultimately more economical.
AtıfScopus6OpenAlex3İncele - MakaleAçık Erişim2021Scopus SJRQ1Analysis 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.
AtıfScopus4WoS5OpenAlex6İncele - MakaleAçık Erişim2021Scopus SJRQ1Investigation 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.
AtıfScopus13WoS12OpenAlex13İncele - MakaleAçık Erişim2021Fuzzy inverse logic: part-1. introduction and bases; [Bulanık ters mantık: kısım-1. giriş ve temeller]
Öztekin, Ertekin
In almost all deterministic and artificial intelligence techniques, for the solution of the scientific problems such as design and control problems, the output estimations are performed depending on manuplations on the values of input variables. With the other words, lots of different values derived from input parameters are tried in order to obtain desired output(s). Contrary to these conventional estimation methods, this study consists of two parts in which a new artificial intelligence method called fuzzy inverse logic(FIL) is developed to determine or estimate the value of the input parameters that give the targeted problem output. In the first part of this study, after providing a brief overview about the method of classical fuzzy logic(FL), the solution approaches and calculation details about FIL are given. In the second part of the study, fuzzy inverse logic method was used to solve one simple mathematical problem and one simple civil engineering problem. After the validity of the developed method was demonstrated by graphics and tables. some evaluations were made about the method.
AtıfScopus2OpenAlex3TR Dizin1İncele - MakaleAçık Erişim2021Phytic 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.
AtıfScopus7WoS5OpenAlex5İncele - MakaleAçık Erişim2021Scopus SJRQ3Wong-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.
AtıfScopus4WoS4OpenAlex5İncele - MakaleAçık Erişim2021Scopus SJRQ2In vitro glycemic index, antioxidant capacity and some physicochemical characteristics of deep-fried sorghum based gluten free chips
Kaplan, Mahmut; Yüksel, Ferhat; Karaman, Kevser
In this study, deep fried gluten free chips were manufactured using sorghum flour at different concentrations (5, 20, 35 and 50 g/100 g) and in vitro glycemic index, total antioxidant capacity and some physicochemical characteristics (dry matter, ash, oil, protein and color) and overall acceptability of the samples were investigated. Protein, oil and total dietary fiber levels of the samples ranged between 5.39–8.28, 23.58–29.10 and 5.59–6.60 g/100 g, respectively and increase in sorghum flour level resulted in an increase in these studied quality parameters of the chips samples. Ferric reducing antioxidant activity and DPPH radical scavenging performance were affected positively by the addition of sorghum flour. Total starch hydrolysis index and estimated glycemic index values were affected by the sorghum flour addition negatively due to the increased total dietary fiber content of the chips samples. All chips samples enriched with sorghum flour showed similar overall acceptability and increased sorghum concentration decreased the preference scores slightly. All these results could be considered for the manufacturing of the gluten free deep fried sorghum based chips samples.
AtıfScopus11WoS9OpenAlex11
İncele - MakaleAçık Erişim2021Scopus SJRQ1Influence of Mg addition and T6 heat treatment on microstructure, mechanical and tribological properties of Al–12Si–3Cu based alloy
BEDER, M.; ALEMDAG, Y.
The aim of the present study was to investigate the influence of Mg addition and T6 heat treatment on microstructure, mechanical and tribological properties of the Al–Si–Cu–Mg alloys. In this context, a series of Al–12Si–3Cu–(0.5–2.5)Mg (wt.%) alloys were produced by permanent mould casting, and then subjected to T6 treatment. Their microstructure and mechanical properties were investigated using OM, XRD, SEM, EDS along with hardness, tension, compression and Charpy impact tests. Dry sliding friction and wear properties of the alloys were studied using a ball-on-disk type tester. It was observed that the microstructure of as-cast Al–12Si–3Cu–Mg alloys consisted of α(Al), Si, θ-CuAl2, β-Mg2Si, Q-Al5Mg8Cu2Si6 and π-Al8Mg3FeSi6 phases. T6 heat treatment gave rise to nearly spherodization of eutectic Si particles, formation of finer θ-CuAl2 and β-Mg2Si precipitates and elimination of Chinese script morphology of β-Mg2Si phase. The addition of Mg up to 2.5 wt.% decreased the hardness, tensile and compressive strengths, tensile elongation and impact toughness of the as-cast and T6-treated alloys and increased their friction coefficient and volume loss. T6 treatment, on the other hand, led to a significant increase in mechanical properties and wear resistance of as-cast alloys.
AtıfScopus35WoS34OpenAlex36İncele - MakaleAçık Erişim2021Scopus SJRQ3Statistical behaviours of earthquake occurrences in the Central Anatolian Region of Turkey: region-time-magnitude analyses
Öztürk, Serkan
The main objective of this work is to make detailed region-time-magnitude analyses by describ-ing the statistical behaviours of earthquakes in the Central Anatolian Region of Turkey. In this scope, several seismic and tectonic parameters such as Mcomp, b-value, Dc-value, Z-value, recurrence times and annual probabilities were evaluated. For the analyses, a homogeneous catalogue including 10,146 earthquakes with 1.0 ≤ Md ≤ 5.7 between 30 July 1975 and 29 December 2018 was used and spatio-temporal changes of earthquake behaviours were mapped for the beginning of 2019. Earthquake magnitudes varied from 1.9 to 3.0 on average, and hence Mcomp was considered to be 2.6. The b-value was calculated as 1.26 ± 0.07, and this relatively large value indicates that small-magnitude events are dominant. The Dc-value was computed as 1.31 ± 0.03. This small value means that distances between epicentres approach the diameter of the cluster, and seismic activity is more clustered at smaller scales or in larger regions. The spatio-temporal analyses of recurrence times suggest that the Central Anatolian Region has an intermediate/long-term earthquake hazard in comparison to occurrences of strong earthquakes in the short term. Several anomaly regions of a small b-value and a large Z-value were found in and around the Tuzgölü Fault Zone, Central Anatolian Fault Zone, Salanda fault and Niğde fault at the beginning of 2019. Thus, a combination of the regions with a lower b-value, a higher Z-value and also moderate recurrence times may give significant clues for the future possible earthquakes, and detected regions may be thought to be the most likely areas for strong/large events in the Central Anatolian Region.
AtıfScopus2WoS1OpenAlex3İncele - MakaleAçık Erişim2021Scopus SJRQ1Effect of cellulose nanofiber-based coating with chitosan and trans-cinnamaldehyde on the microbiological safety and quality of cantaloupe rind and fresh-cut pulp. Part 2: Quality attributes
Ozturk, Samet; Zhang, Jin; Singh, Rakesh K.; Kong, Fanbin
The quality characteristics of fruits and vegetables can be protected with coatings. The presented study aimed to evaluate the effect of cellulose nanofiber (CNF) based coatings with chitosan (CHI) and trans-cinnamaldehyde (TC) on the quality attributes, including weight loss, total soluble solid (TSS) content, firmness, and color of whole and fresh-cut cantaloupe during storage at 22 °C and 4 °C, respectively. Results showed that CNF-based coating was effective in protecting whole cantaloupes from firmness reduction and color change in redness/greenness (a*) and yellowness/blueness (b*) during room-temperature storage for up to 11 days. Coating containing only CNF was not able to prevent the quality changes of fresh-cut cantaloupe during the cold storage, but CNF + CHI/CNF + CHI + TC significantly decreased the weight loss, decelerated the firmness increase and maintained the lightness (L*) of fresh-cut cantaloupe for up to 7 days. The incorporation of chitosan (1%, w/w) improved the protection effect of CNF-based coatings against quality changes during storage for both whole and fresh-cut cantaloupes, but TC (1%, w/w) did not show significant enhancement on the protection effects of coatings for most quality attributes. This study indicates that the CNF-based coatings have the potential to maintain quality attributes of whole and fresh-cut fruits during storage and distribution.
AtıfScopus12WoS8OpenAlex9İncele - MakaleAçık Erişim2021Scopus SJRQ1An Investigation of the Effect of COVID-19 on OCD in Youth in the Context of Emotional Reactivity, Experiential Avoidance, Depression and Anxiety
Seçer, İsmail; Ulaş, Sümeyye
In addition to the serious physical and medical effects on individuals, the COVID-19 pandemic is likely to have short- and long-term psycho-social consequences, especially for young people. Nowadays, with psychological problems becoming more widely recognized in adolescents, it is possible that the fear and anxiety caused by the pandemic will trigger various anxiety disorders, OCD and similar negative outcomes. Considering that psychological qualities such as emotional reactivity and experiential avoidance observed in adolescents may increase the risk of such psycho-social disorders, in this study the relationship between fear of COVID-19 and OCD was investigated in a Turkish sample of 598 adolescents, and the mediating role of emotional reactivity, experiential avoidance and depression-anxiety in this relationship was examined. The data collection was performed online rather than in person because of the COVID-19 threat. A structural equation model was used to determine the direct and indirect predictive effects between variables in data analysis. The results of the study show that the effect of COVID-19 fear on OCD is mediated by emotional reactivity, experiential avoidance and depression-anxiety.
AtıfScopus97WoS98OpenAlex142İncele - MakaleAçık Erişim2021Estimation of ground types in different districts of Gümüşhane province based on the ambient vibrations H/V measurements
Öztürk, Serkan; Beker, Yasemin; Sari, Mahmut; Pehlıvan, Levent
In this study, an attempt was made to estimate the ground types for Torul, Kürtün, Kelkit, Şiran and Köse districts of Gümüşhane, Turkey, by analyzing the predominant frequency and H/V ratio from microtremor data through the single station microtremor H/V ratio of Nakamura technique. For all districts, predominant frequencies show a general distribution between 1.36 and 9.84 Hz, H/V ratios between 1.01 and 9.58. According to these variations, three transient zones can be suggested as i) Z1, stiff rock composed of gravel, sand and other soils mainly consisting of tertiary or older layers with period of 0.1 to 0.2s, ii) Z2, sandy gravel, stiff sandy clay, loam or sandy alluvial deposits whose depths are 5m or greater with period of 0.2 to 0.4s, and iii) Z3, standard grounds other than type Z1, Z2 or Z4 (alluvial deposits whose depths are 5m or greater) with period of 0.4 to 0.8s. These r esults s uggest that p redominant period obtained from predominant frequency shows significant changes based on the soil formation, and H/V ratio highly corresponds to these subsurface properties. Soil-structure interaction can also be evaluated by considering these results and possible resonance risk can be investigated for building resonant frequency in these residential districts in the next. Thus, this type of application and evaluation of microtremor data may provide primary and useful information for other geophysical, geological and geotechnical studies such as planning the seismic resistant infrastructure, detecting the small-scale seismic risks and making a suitable and reliable seismic hazard microzonation in Gümüşhane. Copyright 2021, Yıldız Technical University.
AtıfScopus7WoS4OpenAlex4İncele - MakaleAçık Erişim2021Scopus SJRQ1Effect of heat treatment on mechanical and wear properties of Zn–40Al–2Cu–2Si alloy
SAVAŞKAN, Temel; AZAKLI, Zeki; HEKÌMOĞLU, Ali Paşa
In order to determine the effect of heat treatment on the mechanical and wear properties of Zn–40Al– 2Cu–2Si alloy, different heat treatments including homogenization followed by air-cooling (H1), homogenization followed by furnace-cooling (H2), stabilization (T5) and quench–aging (T6 and T7) were applied. The effects of these heat treatments on the mechanical and tribological properties of the alloy were studied by metallography and, mechanical and wear tests in comparison with SAE 65 bronze. The wear tests were performed using a block on cylinder type test apparatus. The hardness, tensile strength and compressive strength of the alloy increase by the application of H1 and T6 heat treatments, and all the heat treatments except T6, increase its elongation to fracture. H1, T5 and T6 heat treatments cause a reduction in friction coefficient and wear volume of the alloy. However, this alloy exhibits the lowest friction coefficient and wear volume after T6 heat treatment. Therefore, T6 heat treatment appears to be the best process for the lubricated tribological applications of this alloy at a pressure of 14 MPa. However, Zn–40Al–2Cu–2Si alloy in the as-cast and heat-treated conditions shows lower wear loss or higher wear resistance than the bronze.
AtıfScopus17WoS14OpenAlex18İncele - MakaleAçık Erişim2021The Effects of Economic Recessions on Divorce Rates: A Research on Turkey; [Ekonomik Resesyonların Boşanma Oranları Üzerindeki Etkileri: Türkiye Üzerine Bir Araştırma]
Koç, Pınar; Kutlar, Aziz
This study analyses the relationship between short-and long-term relationships between divorce rates and economic recession in Turkey. The asymmetric and time-varying asymmetric causality tests are used to analyse the short-term relationship, the Maki cointegration test is used to analyse the long-term relationship. The dependent variable of the model is the divorce rate. Labour force participation rate of women, unemployment rate, GDP per capita, legal regulations, and economic crises are independent variables. According to the estimation results, unemployment, national income, legal regulations, and economic crises positively affect divorce rates. The time-ric causality test results also indicate a temporary causality relationship between positive income and unemployment shocks.
AtıfScopus2WoS4OpenAlex4TR Dizin3İncele - MakaleAçık Erişim2021A determination of the relationship between the symptoms, hospital anxiety and depression levels, and quality of life patients diagnosed with Covid-19
Sayilan, Samet; Aydin Sayilan, Aylin; Demir Doğan, Melike; Çetinkaya, Emel; Olcayturk, Nuray
Introduction: The worldwide spread of coronavirus over the last 20 years has resulted in its becoming a major threat to health. The virus is thought to be a zoonotic disease spread by means of direct and contact transmission. The purpose of this study was to investigate the symptoms, anxiety-depression levels, and quality of life of patients with Covid-19. Material and methods: This descriptive, cross-sectional research was conducted in an education and research hospital between August and November 2020. An information form, the Hospital Anxiety and Depression Scale, and the Quality of Life Scale were employed as data collection tools. The study was completed with 103 individuals. Results: The mean age of the patients enrolled in the study was 37.77±10.92 years, and 67% were women. Higher anxiety levels were determined in women compared to men (p=0.001) and in married participants compared to unmarried individuals (p=0.010). Significant negative correlation was determined between anxiety and the Quality of Life Scale sub-parameters of general health, physical health, psychological health, and environment. Positive correlation was found between Covid-19 severity and anxiety, and negative correlation between Covid-19 severity and physical health (p<0.001). Conclusion: Higher anxiety was determined among women and married patients in this study, and quality of life (in the four sub-parameters) decreased as anxiety increased. Physical health decreased, while anxiety increased, with the severity of Covid.