Sürdürülebilir Kalkınma Amaçları

Yazarlar

  • BildiriAçık Erişim2018
    OBJECT BASED BUILDING EXTRACTION and BUILDING PERIOD ESTIMATION from UNMANNED AERIAL VEHICLE DATA

    Comert, Resul; Kaplan, Onur; Honkavaara, E.; Komp, K.; Stilla, U.; Jiang, J.; Zhang, H.; Peled, A.; Soergel, U.; Scaioni, M.

    The aim of this study is to examine whether it is possible to estimate the building periods with respect to the building heights in the urban scale seismic performance assessment studies by using the building height retrieved from the unmanned aerial vehicle (UAV) data. For this purpose, a small area, which includes eight residential reinforced concrete buildings, was selected in Eskisehir (Turkey) city center. In this paper, the possibilities of obtaining the building heights that are used in the estimation of building periods from UAV based data, have been investigated. The investigations were carried out in 3 stages; (i) Building boundary extraction with Object Based Image Analysis (OBIA), (ii) height calculation for buildings of interest from nDSM and accuracy assessment with the terrestrial survey. (iii) Estimation of building period using height information. The average difference between the periods estimated according to the heights obtained from field measurements and from the UAV data is 2.86 % and the maximum difference is 13.2 %. Results of this study have shown that the building heights retrieved from the UAV data can be used in the building period estimation in the urban scale vulnerability assessments.

    • SDG 11 · Sürdürülebilir Şehirler ve Topluluklar
    AtıfScopus9OpenAlex10
    Scopusİncele
  • MakaleYalnız künye2018Scopus SJRQ1
    Geometric optimization of an ejector for a 4 kW SOFC system with anode off-gas recycle

    Genc, Omer; Toros, Serkan; Timurkutluk, Bora

    One of the important energy saving tools used in solid oxide fuel cell (SOFC) system is the anode off-gas recycling (AGR) via an ejector which allows the recirculation of the unused fuels in the anode exhaust gas including hot steam which is essential for the elimination of the carbon deposition and the initiation of the reactions in the reformer. In an ejector system developed for the SOFCs, the steam to carbon ratio (STCR) and entrainment ratio are the crucial parameters for the determination of the ejector performance. These parameters can be engineered by modifying the geometric dimensions and operation conditions. This study focuses on the determination of the maximum STCR value and entrainment ratio via numerical geometric analyses for a micro combined heat and power (μ-CHP) system based on 4 kW SOFC, utilizing methane. A detailed numerical procedure for designing an ejector is provided and the ejector performance is investigated for different critical dimensions (throat diameter, nozzle exit angle and nozzle position etc.). The results show that the nozzle position and the nozzle exit angle significantly affect STCR and the entrainment ratio. When the nozzle position increases and nozzle exit angle decreases, the entrainment ratio and STCR is found to increase. The entrainment ratio and STCR are determined as around 7.3 and 2.7, respectively for a specific design created in the study.

    • SDG 7 · Erişilebilir ve Temiz Enerji
    AtıfScopus26WoS23OpenAlex24
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2018Scopus SJRQ4
    Volume calculation of brain structures in migraine disease by using mristudio

    Palancı, Özgür; Kalaycıoğlu, Ahmet; Acer, Niyazi; Eyüpoğlu, İlker; Çakmak, Vildan A.

    Migraine is a neurological disorder that is known as headache and accompanies attacks of neurological and gastrointestinal symptoms and prevents daily life activities of the person. In the literature, the volume changes of many structures in the brain have been investigated using brain magnetic resonance images (MRI) of migraine patients, but it has not yet been investigated whether there is a comprehensive and detailed volume change involving all the structures of the brain. The purpose of this study is to examine the brain structures in a wide range and to determine in which regions the volume changes. In this study, 25 healthy subjects and 25 migraine patients were included in the study. SPSS 15.0 program was used for statistical analysis. The Mristudio was used in our study when we examined the volumes of migraine patients and brain structures of healthy individuals. Statistically significant volume changes were found in the volumes of structures found in the brain frontal, parietal, occipital, temporal lobes. Volumetric changes were assessed in terms of duration of illness and frequency of attacks. In conclusion, our study is compatible with migraine pathophysiology. Structural changes in the brain are thought to be a risk factor for migraine. The evidence on the relationship of regional gray matter volumetric change detected in migraine is unclear. We believe that this ambiguity is caused by the method used.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus2OpenAlex2
    Scopusİncele
  • MakaleYalnız künye2018Scopus SJRQ3
    Automated Model Updating Effect on the Linear and Nonlinear Dynamic Responses of Historical Masonry Structures

    Altunişik, A.C.; Okur, F.Y.; Genç, A.F.; Günaydin, M.; Karahasan, O.

    Finite element models supply the simulation of the problems to obtain the structural behaviors under different loading conditions. The updating processes based on changing the uncertain parameters such as material properties, boundary conditions, meshing size etc. are made to create actual finite element models in order to represent the real conditions of the problems. This procedure can be made using two methods, namely manual model updating and global/local automatic model updating. The global/local automatic model updating procedures are very popular owing to the applicability to all kind of engineering structures, minimizing the differences nearly to zero, availability of damage localization and structural health monitoring. In this paper a historical masonry armory building selected as an application and its finite element analyses, experimental measurements and automated model updating processes are carried out. The finite element model of the structures was developed with ANSYS software and first three natural frequencies are attained. The experimental dynamic characteristics such as natural frequencies, damping ratios and mode shapes are obtained using ambient vibration method. The differences between experimental and numerical frequencies are minimized up to the range of 0–1%, by using local updating procedure. The linear and nonlinear seismic analyses of the building are conducted on initial and updated models. At the end of the analyses, maximum displacements, principal stresses and strains are given with detail. In addition, crack distributions diagrams are attained to validate the stresses accumulation points. It can be seen that there is an increasing trend in the displacement, stress and strain values after finite element model updating both linear and nonlinear analysis. In addition, linear and nonlinear analysis results are compared with each other to evaluate the nonlinear analysis effect. It is concluded that the displacement and strain values are increased after nonlinear analysis. But, there is not any agreement in stress values.

    AtıfScopus17WoS15OpenAlex15
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  • MakaleYalnız künye2018Scopus SJRQ2
    An enhanced scanning-based MPPT approach for DMPPT systems

    Başoğlu, Mustafa Engin

    In this paper, an improved maximum power point tracking (MPPT) approach being low parameter dependency, simple structure and limited search interval has been presented for distributed MPPT photovoltaic (PV) systems. Basically, this approach is based on scanning of power–voltage (P-V) characteristic curve of PV modules in a limited duty ratio interval which makes tracking operation simple, fast and efficiently available in both uniform irradiance and partial shading conditions (PSCs). By limiting the scanning interval of maximum and minimum values of duty ratio via some analyses related to P-V characteristic for PSCs, global MPPT (GMPPT) is achieved in an efficient way. So as to validate performance of the proposed approach, a single-ended primary inductance converter has been used in both simulation and experimental studies. PV simulator has been used as a PV source to obtain different module characteristics with different number of bypass diodes and PV power levels. Both simulation and experimental results clarify that improved MPPT approach realises GMPPT effectively. Due to the high performance results, this approach can be an alternative technique in module-integrated converters, smart modules and PV power optimisers in which single module is used.

    AtıfScopus27WoS23
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2018Scopus SJRQ1
    Indoor and outdoor radon measurements at lung cancer patients’ homes in the dwellings of Rize Province in Turkey

    Özen, Songül Akbulut; Celik, Necati; Dursun, Emrehan; Taskın, Halim

    In this study, indoor and outdoor radon (222Rn) surveys were carried out in the summer and winter seasons in homes of one hundred lung cancer patients in the year 2013–2014. The aim was to investigate the relationship between radon and cancer patients. Lung cancer patients completed a questionnaire concerning their living environment, various physical parameters and living habits. Pearson correlation and t tests revealed no meaningful results between radon concentrations, on one hand, and environmental and personal living habits, on the other hand. Consequently, the BEIR VI model was adapted and 222Rn exposure was estimated to be responsible for about 12% of the lung cancer incidences in the winter season and around 5% in the summer season in the Rize Province. However, due to the limited number of data and numerous parameters that could lead to lung cancer, the estimations done with the model should be taken very lightly. The annual effective doses due to inhalation of indoor and outdoor 222Rn were estimated to be, respectively, 1.43 and 0.94 mSv y−1. The indoor and outdoor annual effective doses were, respectively, close and below the world annual effective dose (1.3 mSv y−1). At the district level, the indoor annual effective dose equivalent in the İyidere district was 4.52 mSv y−1, which was 3.5 times greater than the world average. The number of patients in the majority of the houses in this district was more than one.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus31WoS27OpenAlex33
    ScopusWeb of SciencePubMedİncele
  • MakaleYalnız künye2018Scopus SJRQ3
    Solving power transmission line routing problem using improved genetic and artificial bee colony algorithms

    Eroğlu, Hasan; Aydin, Musa

    In engineering studies, finding the best route from a start point to an end point on pixel-based weighted maps is a big problem for researchers. For this problem many methods and algorithms have been developed until now. The “cost distance” (CD) and “cost path” (CP) tools that are used by a modified Dijkstra’s algorithm and used by Environmental Systems Research Institute’s (ESRI) ArcGIS Desktop 10 software are very fast and most preferred solutions for route optimization problems. Despite the advantages of these tools, they have the disadvantage of making a lot of curves with big angles. Especially in some engineering studies like power transmission lines’ routing, the angle of the curves of the lines should not have big values. For overcoming this problem both genetic algorithm (GA) and artificial bee colony (ABC) algorithm that have been improved and adapted for the problem were used as powerful optimizers to find the best routes with fewer curves in those kinds of optimum route problems. New functions like smart direction sensing and improved random functions were developed for application of GA and ABC algorithms in power transmission lines routing studies. This study showed that the ABC algorithm’s performance is better than GA. The accuracy of the algorithms was proven by comparing the results with the CD–CP tools’ results. The experimental results showed that the improved algorithms gave better performance than Dijkstra’s algorithm.

    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    AtıfScopus15WoS12OpenAlex17
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2018Scopus SJRQ4
    Optimization of drying parameters for chestnut fruits using central composite design

    Koca, I.; Yilmaz, V.A.; Odabas, I.H.; Tekguler, B.

    The chestnut drying process was optimized by Response Surface Methodology (RSM). A central composite design with two numerical factors was selected for modelling the drying process. The numerical factors were air temperature from 40 to 60°C and air velocity from 0.75 to 1.75 m s-1. The investigated responses were color values, including lightness (L*), redness (a*), yellowness (b*), total color changes (ΔE) and browning index (BI). The study revealed that the drying temperature was significantly effective on lightness, redness, total color changes and browning index. However, none of the independent variables were significant on yellowness. The L*, a*, ΔE and BI of chestnuts during drying process were adequately described by RSM models. According to desirability function, the optimum drying conditions of chestnuts were 40°C and 0.75 m s-1 air. At optimum conditions, predicted L*, a*, ΔE and BI values were 76.34, -0.20, 7.45 and 17.00, respectively. Under optimized conditions the experimental values of L* (77.46), a* (-0.36), ΔE (6.31) and BI (16.88) agreed with the predicted values. RSM was not successful to develop a satisfactory model for b* values of chestnuts during drying process.

    • SDG 2 · Açlığa Son
    AtıfScopus2OpenAlex1
    Scopusİncele
  • MakaleAçık Erişim2018Scopus SJRQ2
    Purification and selected biochemical properties of peroxidase from cress (Lepidium sativum sub sp. sativum)

    Altay, Ahmet; Koktepe, Tubanur; Durmaz, Lokman; Topal, Fevzi; Gülçin, İlhami; Köksal, Ekrem

    Cress (Lepidium sativum) is an annual herb from Brassicaceae family, and in some regions. It is known as peppergrass, garden cress, garden pepper-cress, pepperwort, or poor man’s pepper. Cress is an important medicinal plant in some countries including Turkey. This plant has major scientific and therapeutic significance. Peroxidase (POD, E.C.1.11.1.7) is an oxidor-eductase enzyme produced by a number of organisms. In this study, POD enzyme was purified from cress by ammonium sulphate precipitation, gel filtration, and CM-Sephadex ion-exchange chromatographies. K m and V max values were calculated from the Lineweaver-Burk graph for H 2 O 2 and guaiacol substrates and the substrate specificity of POD was investigated. The results showed that substrate specificity of H 2 O 2 is better than substrate specificity of guaiacol for this enzyme. The inhibition effects of three cations (Al 3+ , Cu 2+ , and Cr 3+ ) and one organic compound of cetyl trimethylammonium bromide were performed and their inhibition types were determined. Finally, optimum pH, optimum temperature, optimum ionic strength, and stable pH were determined.

    AtıfScopus14WoS15
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  • MakaleYalnız künye2018Scopus SJRQ4
    Open source library-based 3D face point cloud generation

    Bayram, Bulent; Ozkan, Taskin; Reis, Hatice Catal; Bakirman, Tolga; Cetin, Ibrahim; Seker, Dursun Zafer

    Three dimensional (3D) face and body modeling is widely used in various fields such as plastic surgery, diagnosis of facial or body anomalies, 3D computer games and 3D simulation software. Since, commercial 3D face and body scanners are usually expensive, an alternative solution with lower cost is highly desirable. The objective of this study is to create 3D facial point cloud using Semi Global Image Matching method with minimum number of images utilizing a cost effective method. A non-metric Canon 600D camera with 18 megapixels resolution (3456 × 5184) and 60 mm macro lens have been used for face imaging that have been taken from a distance of 120 cm. Five faces have been modeled by the developed algorithm and scanned by David SLS-2 structured light system for accuracy assessment. Open source Cloud Compare software has been used for comparing the results of proposed method with the structured light system. The mean accuracy of five faces obtained as 90.5%. It has been observed that illumination conditions, uncontrolled movements of face or body, hair and eyebrow have negative impacts on the obtained results. The sufficiency of Semi global image matching method has been tested to create dense point cloud data from three stereo pairs for 3D facial modelling.

    AtıfScopus3WoS2
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2018Scopus SJRQ3
    Geochemistry of Çoruh River Bed Sediments in NE Turkey: Implications in Weathering-Sedimentary Cycle, Provenance, and Metal Pollution

    Eker, Ç.Saydam.; Kiliç, E. Demirkol

    This study defines the source area, sub-aerial weathering, and sedimentary cycle level, as well as heavy metal content and origin, of the Çoruh River bed sediments. The studied sediments are geochemically classified as litharenite based on the ratio of the major element contents. Relative to the Upper Continental Crust (UCC), trace elements Rb, Sr, Ba, Th, U, Zr, Hf, Y, Nb, and Pb are generally depleted; Co, Ni, Cu, Sc, and V are generally enriched; and Au is depleted in some places and enriched in other places. The rare earth element (REE) distributions of the samples exhibit a trend similar to that of the upper continental crust (UCC); however, low to moderate depletion occurs in the bed sediments in UCC. The analyzed samples exhibit low Chemical Index of Alteration (CIA) values, Plagioclase Index of Alteration (PIA) values (<50), CIA/WIP (Weathering Index ratios <1), and substantially high Index of Compositional Variability values (ICV) (>1). Thus, the samples are not chemically mature and are mainly derived from non-altered sources and were exposed the simple cycling history. REEs are depleted in the river bed sediments, unlike the world river average silt, world river average clay, and suspended sediment in world rivers. Minor enrichment of Zn, Sn, and Sc contents, low-to-moderate enrichment of Cu content, very severe enrichment of as content, and extremely severe enrichment of Ni content of the analyzed samples are observed. Consequently, stream bed sediments are derived from intermediate sources close to mid-continental crust rather than felsic sources Low-to-moderate degrees of chemical weathering of these sediments indicate increased tectonic activity, increased erosion, and rapid sedimentation in semiarid to arid conditions in the source regions over time. Thus, the sediments are chemically immature. These sediments are exposed to lithogenic and anthropogenic contamination.

    AtıfScopus19WoS17OpenAlex21
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2018Scopus SJRQ1
    The effect of energy resolution of detection instrument on mass attenuation coefficient

    Çelik, N.; Özen, S.A.; Demirtaş, Ö.F.; Çevik, U.

    The effect of energy resolution of two detection systems, HPGe and NaI(Tl), was determined by Monte Carlo (MC) calculation on mass attenuation coefficients of magnesium (Mg) and tungsten (W). In order to reveal the energy resolution effect, the detectors' collimator diameters were changed from 2 mm to 20 mm while sending collimated photon beams to the absorber material. It was observed that mass attenuation coefficients were increased with increasing collimator diameters. The performances of HPGe and NaI(Tl) detectors were quantified. The calculated results were compared with experimental results for Mg at energy of gamma rays 662 keV for different collimator diameters using both HPGe and NaI(Tl). It was observed that the MC calculation results were in a good agreement with the experimental data within the relative error from around 4% to 8%.

    AtıfScopus8WoS7OpenAlex7
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2018Scopus SJRQ2
    Differential scanning calorimetry (DSC) and Ni+2 release analysis of NiTi-shape-memory dental alloys coated by micro-arc oxidation (MAO) method

    Yeşildal, Ruhi; Karabudak, Filiz; Şüküroğlu, Ebru Emine; Şüküroğlu, Süleyman; Zamanlou, Hamid; Bayındır, Funda; Şen, Sadri; Totik, Yaşar

    This study aims to prevent the release of Ni+2 and increase the biocompatibility of NiTi-shape-memory dental alloys with the micro-arc oxidation (MAO) coating by preserving the shape-memory feature in the oral environment. The TiO2-ceramic coating and Ag-doped TiO2 coating have been grown on shape-memory, co-atoms’ dental NiTi alloys with the MAO method. Biocompatibility properties of the coating were determined by in-vitro tests. In-vitro tests have been made as retention tests in a simulated body fluid (SBF). Whether the grown surface coating impacts the shape-memory properties of the base material or not has been determined by differential scanning calorimetry (DSC) analysis. It was observed as a result of retention tests that bone-like apatite form occurred on the surface of TiO2-coated NiTi and Ag-doped TiO2-coated NiTi coating. It was determined as a result of retention tests in SBF that the Ni+2 release rate from the base material was below the limit of detection in coated samples. As a result of DSC analysis, it was not observed any significant changes in transformation temperature with the MAO coating. It was concluded that the thin-film coatings formed by MAO technique prevent the release of Ni in the oral environment and increase the biocompatibility by preserving shape memory properties of NiTi dental alloys.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus10WoS9OpenAlex10
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2018Scopus SJRQ1
    Carrier transport mechanism and bipolar resistive switching behavior of a nano-scale thin film TiO2 memristor

    Gul, Fatih

    A titanium dioxide (TiO2) based memristor device having an active layer thickness of 10 nm was fabricated using radio frequency (RF) reactive sputtering and its resistive switching characteristics and carrier transport mechanisms were investigated. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were used to confirm the structural properties of the device. Measurement of the time-dependent current-voltage (I-V-t) was used to characterize resistive switching and memristive behavior. The characteristic pinched hysteresis I-V loops of the memristor were apparent. Bipolar and homogeneous resistive switching characteristics and a forming voltage of 2 V were detected in the device. The retention time exceeded 103 s and the endurance test was reasonably acceptable. In addition, the carrier transport mechanism of the device was revealed. The linear region of the low electric field demonstrated ohmic behavior, whereas the non-linear high electric field region was dominated by a Schottky emission carrier transport mechanism. A Poole-Frenkel emission mechanism acted as a secondary conduction mechanism. It was proposed that the Poole-Frenkel and Schottky emission mechanisms were associated with oxygen vacancies in the TiO2.

    AtıfScopus69WoS69OpenAlex77
    ScopusWeb of Scienceİncele
  • BildiriYalnız künye2018
    Seasonal Variation of the Monthly Efficiencies of Thin Film PV Modules

    Özden, Talat; Turan, Raşit; Akmoǧlu, Bülent Gültekin; Zaz, Y.; Essaaidi, M.

    Outdoor testing of solar photovoltaic (PV) modules must be carried out at different climates as PV power plants nowadays are installed and continues to be installed in many countries. Present study is outdoor testing results and analyses of 5 thin film modules in Ankara, Turkey. The analyses are carried out using monthly efficiencies of the modules that are derived using the energy yield and input. The average efficiencies of the CIS, CIGS and μc-Si/a-Si thin film modules are. We present the monthly and average efficiencies and discuss their variations with the parameter: input, ambient temperature and relative humidity. We also carried out seasonal analyses using Pearson's correlation coefficient and find out that the efficiencies are differently dependent on the above mentioned parameters. This arose a new open question on differentiation of the strength of the effect of each parameter on the monthly efficiencies.

    • SDG 7 · Erişilebilir ve Temiz Enerji
    • SDG 13 · İklim Eylemi
    AtıfScopus1WoS1OpenAlex1
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2018Scopus SJRQ2
    Investigation of Antibacterial Susceptibility of Ag-Doped Oxide Coatings onto AZ91 Magnesium Alloy by Microarc Oxidation Method

    Sukuroglu, Ebru Emine

    This study is focused on enhancing surface characteristics of AZ91 alloy with the microarc oxidation (MAO) method and bringing in antibacterial susceptibility to it. It is aimed to bring in antibacterial effect of silver (Ag) to AZ91 magnesium base materials covered with the MAO method. The structural and chemical compositions of the coating were analysed by using XRD, SEM, and EDS. In order to analyse antibacterial susceptibilities and bacteria adhesions, bacteria are marked using crystal violet in antibacterial efficacy tests. Susceptibility of coatings to Staphylococcus aureus (S. aureus-ATCC 29213) bacteria having high adhesion is analysed. In the study, it is concluded that the silver-containing coatings have a lot poor bacterial susceptibility than silver-free coatings, and noncoated samples have very strong bacterial susceptibilities. When the antimicrobial activity of the samples coated on silver-containing electrolyte is evaluated (zone diameter ∼40 mm), it is found as sensitive. Antimicrobial activity of samples coated in silver-free electrolyte is found as medium-sensitive (zone diameter ∼15 mm), and uncoated samples are observed to form any zones against bacterial infection.

    AtıfScopus18WoS14OpenAlex19
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2018Scopus SJRQ3
    Textural, rheological and pasting properties of dough enriched with einkorn, cranberry bean and potato flours, using simplex lattice mixture design

    Yuksel, F.; Campanella, O.H.

    The aim of this study was to analyse the effects of the addition of einkorn, cranberry bean and potato flours on the pasting characteristics of the mixture as well as the rheological properties of the dough formed. An experimental design using a simplex lattice mixture design was employed. The pasting parameters of the samples increased with the addition of cranberry bean and einkorn flours due to their high protein content. The water absorption capacities of the doughs were significantly affected by the polar nature (e.g. potato flour) and protein content (e.g. cranberry bean) of the flours. The creep-recovery properties of the doughs were analysed using the Burger model. Results showed that doughs enriched with potato flour exhibited weak elastic properties and behaved as a highly viscous material. Textural profile analysis of the doughs showed that their structure became firmer with addition of einkorn, cranberry bean and potato flours. The determination coefficient for the samples was higher than 0.70 in the simplex lattice mixture design.

    • SDG 2 · Açlığa Son
    AtıfScopus7WoS7OpenAlex7
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2018Scopus SJRQ2
    Single production of the excited electrons in the future FCC-based lepton-hadron colliders

    Caliskan, A.; Kara, S.O.

    We study the composite electron production at the FCC-based three electron-proton colliders with the center-of-mass energies of 3.46, 10 and 31.6 TeV. For the signal process of ep → e→ X eγX, the production cross-sections and decay widths of the excited electrons have been calculated. The differences of some kinematical quantities of the final state particles between the signal and background have been analyzed. For this purpose, transverse momentum and pseudorapidity distributions of electron and photon have been obtained and the kinematical cuts for discovery of the excited electrons have been assigned. We have finally determined the mass limits of excited electrons for observation and discovery by applying these cuts. It is shown that the mass limit for discovery obtained from the collider with √s = 31.6 TeV (called PWFA-LC-FCC) is 22.3 TeV for the integrated luminosity Lint = 10fb-1.

    AtıfScopus7WoS6
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  • BildiriAçık Erişim2018
    Determining photovoltaic module performance and comparisons

    Karaveli, Abdullah Bugrahan; Ozden, Talat; Akinoglu, Bulent G.

    Knowing electricity production potential of a photovoltaic (PV) system prior to installation is very beneficial for the investor to see the feasibility of the investment. There are three procedures that can be followed to calculate the potential electricity production of any system under different conditions. These are installation of sample systems and gathering data over time, the use of some databases/software programs to reach the performances and developing new model/methodology to make these estimations. It is obvious that installation of PV systems everywhere is neither technically nor economically conceivable. On the other hand, global software programs may not reflect local conditions to calculations. Consequently, there is a need to develop methodology that is able to derive location specific equations and coefficients and make accurate estimations. Its accuracy can be controlled by validating the results for some locations with the measured values from already installed PV power plants (PV PP). So, in this study we initially develop a methodology to calculate efficiency and electricity production performance of some modules for Ankara and compare the results with the measured values owing to the system installed on the roof of the Middle East Technical University Solar Energy Research Center (METU GUNAM) in Ankara/Turkey. The methodology initially calculates solar irradiation falling on the modules that is the input. Then the performance of the module is calculated by using developed methodology. There are also some online software programs to calculate the performances, such as EU PVGIS and PV WATTS. We analyzed and used these software programs and compare their results with the results of newly developed methodology. As proven through mean-bias error (MBE), root-mean-square error (RMSE) and mean absolute error (MAE) statistical comparison methods, the methodology of this study has given the most accurate results.

    • SDG 7 · Erişilebilir ve Temiz Enerji
    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    • SDG 13 · İklim Eylemi
    AtıfScopus2OpenAlex4
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2018Scopus SJRQ2
    Earthquake hazard potential in the Eastern Anatolian Region of Turkey: seismotectonic b and Dc-values and precursory quiescence Z-value

    Öztürk, S.

    The Eastern Anatolian Region of Turkey is one of the most seismically and tectonically active regions due to the frequent occurrence of earthquakes. Thus, the main goal of this study is to analyze the regional and temporal characteristics of seismicity in the Eastern Anatolia in terms of the seismotectonic b-value, fractal dimension Dc-value, precursory seismic quiescence Z-value, and their interrelationships. This study also seeks to obtain a reliable empirical relation between b and Dc-values and to evaluate the temporal changes of these parameters as they relate to the earthquake potential of the region. A more up-to-date relation of Dc = 2:55–0:39*b is found with a very strong negative correlation coefficient (r =–0.95) by using the orthogonal regression method. The b-values less than 1.0 and the Dc-values greater than 2.2 are observed in the Northeast Anatolian Fault Zone, Aşkale, Erzurum, Iğdır and Çaldıran Faults, Doğubeyazıt Fault Zone, around the Genç Fault, the western part of the Bitlis-Zagros Thrust Zone, Pülümür and Karakoçan Faults, and the Sancak- Uzunpınar Fault Zone. In addition, the regions having small b-values and large Z-values are calculated around the Genç, Pülümür and Karakoçan Faults as well as the Sancak-Uzunpınar Fault Zone. Remarkably, the combinations of these seismotectonic parameters could reveal the earthquake hazard potential in the Eastern Anatolian Region of Turkey, thus creating an increased interest in these anomaly regions.

    AtıfScopus51WoS36OpenAlex53
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