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- MakaleYalnız künye2022Scopus SJRQ1Performance comparison of deep learning and machine learning methods in determining wetland water areas using EuroSAT dataset
Günen, Mehmet Akif
Wetlands are critical to the ecology because they maintain biodiversity and provide home for a variety of species. Researching, mapping, and conservation of wetlands is a challenging and time-consuming process. Because they produce temporal and geographical information, remote sensing and photogrammetric approaches are useful tools for analyzing and managing wetlands. In this study, the water areas of five different wetlands obtained with Sentinel-2 images in Turkey were classified. Although obtaining large amounts of high-dimensional dataset labeled for various land types is costly, it is a significant advantage to use it after model training in a wide range of applications. In this paper, the EuroSAT dataset was used in the validation process. Proposed deep learning–based 1D convolutional neural networks (CNN) and traditional machine learning methods (i.e., support vector machine, linear discriminant analysis, K-nearest neighborhood, canonical correlation forests, and AdaBoost.M1) were compared quantitatively (i.e., accuracy, recall, precision, specificity, F-score, and image quality assessment metrics) and qualitatively. Finally, pairwise comparison was made with chi-square-based McNemar’s test. There is a statistical difference between 1D CNN and machine learning method (except the support vector machine vs linear discriminant analysis in Test 1 area). CNN models outperform machine learning algorithms in terms of non-linear function approximation and the ability to extract and articulate data features. Since 1D CNNs can process data in a highly complex and unique feature space, they are very successful in segmenting strongly related and highly correlated discrete signals. It also has advantages over machine learning methods for water body extraction in that it can be integrated with sophisticated image pre-processing and standardization tools, is less susceptible to low-level random noise, and provides shift in variations and contrast-invariant image local transforms.
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İncele - MakaleAçık Erişim2020Scopus SJRQ3Effects of elevation on the aboveground biomass and carbon stock in the oriental beech (Fagus orientalis lipsky) forests of the Sinop region, Turkey
Kahyaoğlu, N.; Kara, Ö.; Güvendi, E.
In this study it was our aim to assess the amount of aboveground biomass and carbon stock of beech stands based on elevation. To achieve this, in the research area, 55 trial sites were chosen by selective sampling method depending on elevation climatic zones (400–600 m, 600–800 m, 800–1000 m). In these trial areas, 55 trees were cut down and the weights of their bark, leaves, stem and branches were determined. The carbon content of each component was calculated. The results of the study showed that, in all elevation zones, the stem wood had the highest average biomass and carbon stock values of all the tree components (for the 400–600 m, biomass was 199.19 kg and carbon stock was 95.82 kg; for the 600–800 m, biomass was 378.75 kg and carbon stock was 182.49 kg; for the 800–1000 m, biomass was 372.56 kg and carbon stock was 183.39 kg). This was followed by the branches, bark and leaves in descending order. The aboveground biomass in the single tree components of leaves, branches, stem and total biomass, all except the biomass of their bark varied with elevation in oriental beech stands, which are economically significant species in Turkey.
AtıfScopus4WoS3OpenAlex8İncele - MakaleAçık Erişim2019Scopus SJRQ2Frictionless Contact Problem for a Functionally Graded Layer Loaded Through Two Rigid Punches Using Finite Element Method
Polat, A.; Kaya, Y.; Bendine, K.; Özşahin, T.Ş.
In this study, continuous contact problem in the functionally graded (FG) layer loaded with two rigid flat blocks resting on the elastic semi-infinite plane was analyzed by the finite element method. The two-dimensional numerical model of the FG layer was made with the software added to the ANSYS program. This software can be adapted to all contact problem types by making minor changes. The accuracy check of the program was performed by comparing with the analytical solution of the problem by homogeneous layer and its solution by the finite element method. So, fast and practical solutions can be obtained by the developed finite element method on many applications such as; automotive, aviation and space industry applications. The comparisons made showed that the proposed solution gave good results at acceptable levels. In the problem, it was thought that all surfaces were frictionless. The external loads P and Q were transmitted to the FG layer via two flat rigid blocks. Normal stresses between the FG layer and the elastic plane, initial separation loads, initial separation distances and contact stresses under the blocks were investigated for various dimensionless quantities.
AtıfScopus14WoS14OpenAlex11İncele - Kitap BölümüYalnız künye2020Exchange rate pass-through to inflation: The case of Turkey
Koç, Pinar
The exchange rate volatility affects to domestic price level via production costs in countries where production level depends largely on import inputs. Turkey is also one of the countries whose production level depends largely on import inputs. Thereby intermediate good import accounts for about of 76 % total import. It is expected that the exchange rate pass-through to inflation is high in Turkey. In this context, in this study, the validity and stability of the pass through effect hypothesis was analyzed in Turkey for the period 1990:01-2019:01. According to the results of the study, the pass-through effect hypothesis is valid in Turkey.
- MakaleYalnız künye2020Scopus SJRQ2Effects of voltage on the components of surface integrity of Al2O3 ceramic coatings on AA2024 by plasma electrolytic oxidation
Matin, Reza; Totik, Yasar; Sukuroglu, Ebru Emine; Efeoglu, Ihsan; Santos, Telmo G.
It is said that plasma electrolytic oxidation (PEO) is considered as an effective technique to boost the surface properties of light materials by means of forming ceramic films on their surfaces. In this study, three different voltage values were applied to the PEO process to AA2024 so that Al2O3 ceramic coatings were directly supplied for AA 2024 substrates by PEO and it is focused on the adhesion of interface between coating and substrate. All of the cases such as microstructure, phase composition, thickness, roughness and hardness of Al2O3 ceramic coatings were assayed by X-ray diffraction (XRD), scanning electron microscopy (SEM), Atomic-force microscopy (AFM), Eddy Current Non-destructive testing and microhardness test, respectively. The results showed that roughness, hardness and thickness of the coatings were increased as we increased the voltage. Therefore, it could be claimed that the voltage parameters have an important role in the unified coating on the metal surface as it is directly connected with the morphologies of the PEO coating.
AtıfScopus10WoS8OpenAlex12İncele - MakaleYalnız künye2020Scopus SJRQ2Source Identification Problem for a Parabolic Equation with Multipoint Nonlocal Boundary Condition
Ashyralyyev, Charyyar; Akkan, Pinar
We study a source identification problem for a parabolic equation with multipoint nonlocal boundary condition. Stability estimates for the solution of abstract source identification problem are established. In application, stability estimates for the solution of the overdetermined mixed boundary value problem for multidimensional parabolic equation are obtained. The first and second order of accuracy difference schemes for the approximate solution of this problem are constructed. Stability estimates for solutions of these difference schemes are proved. Numerical illustration for a simple test problem is presented.
AtıfScopus7WoS6OpenAlex7İncele - MakaleYalnız künye2020Scopus SJRQ2Series tuned mass dampers in vibration control of continuous railway bridges
Araz, Onur; Kahya, Volkan
This paper presents the applicability of series tuned mass dampers (STMDs) to reduce the multiple resonant responses of continuous railway bridges under high-speed train. The bridge is modeled by two-span Bernoulli-Euler beam with uniform cross-section, and a STMD device consisting of two TMD units installed on the bridge to reduce its multiple resonant vibrations. The system is assumed to be under the action of a high-speed train passage which is modeled as a series of moving forces. Sequential Programming Technique (SQP) is carried out to find the optimal parameters of the STMD that minimizes the maximum peak responses of the bridge. Comparisons with the results available in the literature are presented to demonstrate the effectiveness and robustness of STMD system in reducing the multiple resonant responses of the continuous railway bridges under high-speed trains.
AtıfScopus26WoS25OpenAlex14İncele - MakaleAçık Erişim2020Scopus SJRQ3Single production of composite electrons at future sppc-based lepton–hadron colliders
Caliskan, A.
We consider the production of excited electrons with spin-1/2 at future SPPC-based electron–proton colliders with center-of-mass energies of 8.4, 11.6, 26.6, and 36.8 TeV. These exotic particles are predicted in the composite models. We calculate the production cross sections and concentrate on the photon decay channel of the excited electrons with the process of ep → e*X → eγX. The pseudo rapidity and transverse momentum distributions of the electrons and photons in the final state have been plotted to determine the kinematical cutoffs best suited for discovery of the excited electrons. By applying these cutoffs we compute 2σ, 3σ, and 5σ contour plots of the statistical significance of the expected signal in the parameter space (L, m*), where L denotes the integrated luminosity of the collider and m* is the mass of the composite electrons.
AtıfScopus2WoS2OpenAlex3İncele - KitapYalnız künye2021Understanding Environmental Policy After Covid-19
Uğur, Ömer; Cengiz, Emre
Environmental and climate problems have gained a global dimension and constitute one of the important issues of world politics and economies. The necessity of all states to act together on these problems, which threaten the present and future of humanity, and find the solution has revealed the “global” character of the process. The interdependence created by economic development and environmental problems brought a new meaning and dimension to both national and international politics. Especially the recent pandemic has made the global nature of environmental issues more understandable. In this context, it seems necessary to create a work that deals with current debates in the field, which will help identify the problems in the field and find solutions to them.
AtıfOpenAlex1İncele - MakaleAçık Erişim2021Scopus SJRQ3Security system with RFID control using E-KTP and internet of things
Çetin, Gökhan; Fadali, M. Sami
This paper presents an optimal bandwidth allocation method for a networked control system (NCS) which includes time-driven sensor, event-driven controller and random channels. A hidden markov model (HMM) with a discretized state space is formulated for the random traffic to predict the network states using a suitable data window. Network bandwidth is allocated based on the predicted traffic state subject to bounds on the deterministic traffic that guarantee acceptable NCS performance and do not exceed hardware limitations. Bandwidth allocation uses l1 minimization of unmet bandwidth demand. A stability condition is derived for a variable but bounded sampling period interval. Computer simulation results show the effect of varying the number of discrete states for the HMM and the window width on bandwidth allocation. The results compare favorably with a published approach based on fuzzy logic.
AtıfScopus1OpenAlex2İncele - Kitap BölümüYalnız künye2020Working Capital Management and Firm Performance of Turkish Companies
Erdoğan, Mahmut
- MakaleAçık Erişim2021Scopus SJRQ3Tarragon (Artemisia dracunculus l.) could alleviate negative effects of stocking density in laying hens
Kaya, H.; Karaalp, M.; Kaynar, Ö.; Tekçe, E.; Aksakal, A.; Bayram, B.
The study was conducted to determine the effects of stocking density (SD, 5 or 7 layers/cage) and tarragon (Artemisia dracunculus L.) diet supplementation at four levels (0, 1.2, 6 and 12 g/kg feed) on performance, certain egg characteristics, serum, liver, egg yolk and small intestine bacteria parameters in laying hens. The experiment was carried out over a period of 8 weeks, with 192 Lohman Brown commercial hybrids at 50-w-age. The results showed that an increased SD reduced feed intake (FI; p<0.01) and egg production (p<0.05), but had no effect on the weight gain, feed conversion ratio, damaged egg ratio, egg weight and egg quality (p>0.05) parameters. The supplementation of tarragon to the diet reduced the FI and damaged egg ratio (p<0.01), and improved egg production and FCR (p<0.01). While an increased SD reduced serum total antioxidants (p<0.05), it elevated corticosterone (CORT) and total oxidant serum (TOS) (p<0.05). Tarragon was found to enhance total immunoglobulin (p<0.05), but to decreased the CORT and TOS of the serum (p<0.05). An increased SD raised the malondialdehyde (MDA) in the serum (p<0.001), liver (p<0.05) and yolk (p<0.001). Tarragon supplementation reduced MDA of the serum (p<0.05), liver (p<0.001) and yolk (p<0.001). E. coli and total Mesophilic Aerobic Bacteria counts in the small intestine were raised (p<0.001) with increased SD. Tarragon decreased (p<0.05) mesophilic aerobic bacteria. It was thus found that, tarragon supplementation can be considered generally effective in improving performance parameters, alleviating stress-induced negativities, reducing lipid peroxidation, regulating the immune system and controlling some intestinal microorganisms.
AtıfScopus11WoS10OpenAlex10İncele - MakaleAçık Erişim2019Region-Time-Magnitude Analyses of the Seismicity in and around the Central Anatolian Region and Current Earthquake Potential; [Orta Anadolu Bölgesi ve Civarındaki Depremselliğin Bölge-Zaman-Magnitüd Analizleri ve Güncel Deprem Potansiyeli]
Öztürk, Serkan
The purpose of this study is to make detailed statistical analyses of earthquake occurrences in and around the Central Anatolian Region of Turkey and to forecast the possible earthquake regions in the future. In this scope, by performing the region-time-magnitude analyses of seismotectonic variables such as Mc-value, b-value, Dc-value, Z-value, the current/future earthquake potential was defined. b-value was computed as 1.26±0.07 by taking Mc=2.6 and this large value indicates that the earthquakes with small magnitude are dominant. Dc-value was calculated as 1.31±0.03 and this relatively small value shows that distance between the epicenters approaches the diameter of cluster, and earthquake activity is more clustered in larger regions/at smaller scales. Anomaly regions with low b-value and large Z-value at the beginning of 2019 were found in and around Tuz Gölü Fault Zone, Central Anatolian Fault Zone, Salanda and Niğde faults. As an important result, these regions may be considered as the most likely regions for strong/large earthquakes in the future.
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İncele - MakaleYalnız künye2020Scopus SJRQ2Determination of the environmental natural radioactivity and mapping of natural background radioactivity of the Gumushane province, Turkey
Kaya, Selim; Kaya, Ali; Çelik, Necati; Kara, Rasim Taylan; Taşkın, Halim; Koz, Bahadır
The aim of the study is to determine the ambient radiation level in Gumushane province. With this aim, the gamma dose ratios absorbed in the air were surveyed by a portable gamma detector. The activity concentrations of 226Ra, 232Th, 40K, and 137Cs in soil samples have been measured by the gamma spectrometric analysis system. The gross alpha and beta activity concentrations in drinking water were also determined by the alpha and beta counting system. By considering the geological structure, the soil samples have been obtained from 62 different spots. In addition, 77 samples of natural and tap water have been collected from different points of the province. The samples were analyzed at the Cekmece Nuclear Research and Training Center in Turkey. Absorbed gamma dose rates in the air were measured in 338 different points in the studied area.
AtıfScopus5WoS4OpenAlex7İncele - Kitap BölümüYalnız künye2020The European ombudsman: A tool for the institutionalization of democracy at the union level
Dogan, Kadir Caner
- MakaleAçık Erişim2021Global stability of Susceptible Diabetes Complication (SDC) model in discrete time
Şi̇Şman, Şeyma; Merdan, Mehmet
In this study, the mathematical model (DC) of diabetes disease is discussed. This model divides people into (D) uncomplicated and (C) complex diabetics two. In addition, diabetes is a disease known to be caused by genetic and environmental factors, and this factor is one of the main causes of genetic disorder at birth. Considering these two factors, the diabetes complication (SDC) model, which is sensitive from the diabetes complication (DC) model, is being developed. In this model, the responsive diabetes complication (SDC) model of a nonlinear system of differential equations is transformed into a discrete-time system of equations. The positivity and limitation of Model solutions were examined R0 the basic increment number is calculated. If R0 < 1, it has a global asymptotically stable balance for the situation where there is no genetic disorder at birth, and for R0 < 1, the system has an unstable balance. In addition, random behavior of the discrete model was examined for different probability distributions.
AtıfScopus2WoS2OpenAlex4İncele - BildiriYalnız künye2022Scopus SJRQ4Assessment of Rapid Urbanization Effects with Remote Sensing Techniques
Yagmur, Nur; Dervisoglu, Adalet; Bilgilioglu, B. Baha
Istanbul is the most populous city in Turkey. The population, which was approximately 5.5 million in 1985, has reached 15.5 million in 2020. Population growth is the most important factor behind human activities that put pressure on the environment. An increasing population means depletion of limited resources, increasing environmental problems, and rapid urbanization. In parallel with the increase in population and urbanization, there has also been an increase in demand for housing, leading to new residential areas in almost every district of Istanbul. This study examined the transformation from vegetation areas to residential areas between 1985 and 2020 in a selected region in Buyukcekmece, one of the 39 districts of Istanbul. The relationship between land use and land cover (LULC) change in the area and Land Surface Temperature (LST) change caused by urbanization was analyzed. It is seen that the built-up area has increased from 57.1 ha to 781.4 ha in 35 years. In every five years, an increase in surface temperatures was determined in parallel with increasing urbanization, and this increase was determined as about 5.4℃ from 1985 to 2020. Also, when the temperature data of the Buyukcekmece Meteorological station is analyzed, it is seen that there has been an increase of approximately 2 ºC in air temperatures in the last five years. In addition, movements were observed in the stability of structures in rapid urbanization areas after analyzing with the PSI time series InSAR method. The main causes were determined as construction sites around the buildings and geological conditions of the ground, which are triggered by urbanization.
AtıfScopus1OpenAlex2İncele - Kitap BölümüYalnız künye2019The effectiveness of city councils in local politics in Turkey: The case of Gümüshane city council
Kalkisim, Hasan Mahmut
- MakaleYalnız künye2020Scopus SJRQ1A novel billing approach for fair and effective demand side management: Appliance level billing (AppLeBill)
Çakmak, Recep; Altaş, İsmail Hakkı
Demand side management (DSM) is an important part of smart electrical grid studies due to high energy efficiency it provides. Effective DSM techniques are hinged on participation level of the customers and control manner of their loads so if there is no fair and appropriate management, customers will not embrace demand side management applications. Besides, the customers might not participate to the demand response process willingly if their comforts are not considered. Therefore, the DSM systems must consider fairness and customer's comfort as well as distribution system objectives. Multifarious DSM systems have been proposed in the literature, however, the fair billing has not included as a parameter in most of these studies. This paper introduces a novel billing approach based upon appliance level billing (AppLeBill) for fair and effective demand side management. The proposed AppLeBill idea offers a billing strategy such that time-shiftable appliances (TSAs) in a residence may have a separate billing rate rather than a single billing rate for total electricity usage. The proposed AppLeBill concept includes three different schemes which are explained and simulated in order to compare each other in terms of their potential benefits.
AtıfScopus28WoS20OpenAlex25İncele - MakaleYalnız künye2021Scopus SJRQ2Enological properties of red wine produced from native Kösetevek grapes (Vitis vinifera L.) cultivated in Eastern Anatolia
Arpa Zemzemoglu, Tuba Eda; Darıcı, Merve; Cabaroglu, Turgut
The aim of this study was to determine the potential of red wine production from the Kösetevek grape variety (Vitis Vinifera L.) cultivated in Elazig province of Turkey and to define the characteristics of Kösetevek wines. To determine the grapes for wine production quality, the general composition, phenolic compounds, aroma compounds and sensory analysis of the wines were carried out. Aroma compounds were performed by solid-phase extraction (SPE) and then analyzed by gas chromatography (GC) along with gas chromatography/mass spectrometry (GC/MS). Results showed that the red wines obtained from Kösetevek grapes consisted of 50 aroma compounds for 2014 vintages and 49 aroma compounds for 2015 vintages. Esters were the main components contributing to the Kösetevek wine aroma along with ethyl hydrogen succinate and ethyl–4–hydroxy butanoate. The amount of total phenolic compounds, total anthocyanin, and the tannin in Kösetevek wines were found to be between 3705.45 and 3015.63 mg/L, 554.25–502.35 mg/L, and 4.5–3.95 g/L at 2014–2015 vintages, respectively. As to sensory evaluation, Kösetevek wines were characterized as a deep purple color, middle to high body, and rich in red fruit (cherries, plums), and dried fruit odors. This study has provided enological properties and aroma characterization of Kösetevek wines. The results of the study showed that Kösetevek wines could be considered as an alternative to other wines obtained from native grape varieties of the region.
AtıfScopus4WoS4OpenAlex4İncele
