Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Dertli, Enes(116)
- Şahin, Engin(48)
- Kaya, Yunus(46)
- Özen, Soner(46)
- İspirli, Hümeyra(45)
- Pat, Suat(44)
- Şenay, Volkan(42)
- Korkmaz, Şadan(36)
- Yilmaz, Mustafa Tahsin(33)
- Kutlu, Naciye(32)
- Cuce, Erdem(31)
- Öner, Erdal(31)
- Artar, Musa(30)
- Ertugrul, Mehmet(29)
- Hasar, Ugur Cem(29)
- Mercan, Emin(28)
- Bayraktar, Bülent(27)
- Bayram, Sinan(27)
- Can, Zehra(25)
- Ecem Bayram, Nesrin(25)
- Çolak, Murat(23)
- Özdemir, Akın(23)
- Cuce, Pinar Mert(22)
- Sert, Durmuş(22)
- Ayata, Ümit(21)
- Bayram, Ozkan(21)
- Dirican, Ebubekir(20)
- Abdioglu, Murat(19)
- Ayazoglu, Rabil(19)
- Birinci, Ahmet(19)
- Kamiloğlu, Aybike(19)
- Gerçek, Yusuf Can(18)
- Taylan, Osman(18)
- Tozlu, Alperen(18)
- Gul, Volkan(15)
- Hasar, Ugur C.(15)
- Kadakal, Mahir(15)
- Sagdic, Osman(15)
- Ergün, Mustafa(14)
- Kadakal, Huriye(14)
Yayınlar
- MakaleAçık Erişim2021Scopus SJRQ1The effect of sustainable development on economics complexity in oecd countries; [El efecto del desarrollo sostenible en la complejidad económica de los países de la ocde]
Yaprakli, Sevda; Özden, Erdemalp
Economic complexity showing a holistic measure of countries' economic productive power and characteristics has become a new tool for understanding the dynamics of the economy. Examining the relationship between sustainable development and this new tool is vital in determining new policies. By applying panel data of OECD countries covering different development levels from 1996 to 2017 to a data-driven dynamic econometric model, the research provides fresh insight between sustainable development and economic complexity. The results indicate that economic complexity is significantly affected by sustainable developments’ economic indicators such as GDP, FDI, R&D expenditure, social indicators such as human development, income inequality, and environmental indicators such as production-based CO2 emissions, renewable energy consumption, and greenhouse gas. The research, consequently, suggests that switching to technology and knowledge-based production processes, expanding qualified production factor capacity, raising social living standards, and making investments in the green economy will foster economic complexity while ensuring stable sustainability.
AtıfScopus8WoS3OpenAlex7
İncele - MakaleYalnız künye2021Scopus SJRQ2Vitamin, mineral, polyphenol, amino acid profile of bee pollen from Rhododendron ponticum (source of “mad honey”): nutritional and palynological approach
Ecem Bayram, Nesrin
In this study, it was aimed to characterize the pollen collected by bees from the Rhododenron ponticum plant, which is the source of mad honey, in terms of some parameters. In the first stage, the botanical origin of the sample was confirmed by palynological analysis supported by light microscopic images. Then, the chemical profile of Rhododenron ponticum bee pollen was examined in terms of 31 elements, 42 amino acids, 33 phenolics and vitamins A, B1, B2, B5, B6, B7, B12, C, E, K1 and K2. The total individual phenolic compound content of Rhododendron ponticum bee pollen was determined as 11928.23 µg/100 g, total element content as 13997.75 mg/kg, total free amino acid content as 149466.11 µg/g and total vitamin content as 20509.37 µg/100 g. In addition, it was characterized by a low content of vitamin A (retinol), B7, B12, K2, as well as a deficiency of vitamin K1. As a result of analysis with LC-MS-MS, it was found that it contains L-asparagine and myricetin in a significantly higher concentration compared to other amino acids and phenolic compounds. However, the presence of phenolic compounds (myricetin, epicatechin, tyrosol etc.) and amino acids (L-asparagine, gamma-aminobutyric acid, L- Tryptophan etc.) with significant biological activity indicates that this product is a bee product with high medicinal properties. Moreover, the significant presence of Mg, P, Fe and Ca, high K/Na ratio, vitamin C, B2, B5 and B6 content makes bee pollen collected from Rhododendron ponticum plant attractive for diets.
AtıfScopus36WoS27OpenAlex36İncele - MakaleYalnız künye2021Scopus SJRQ1The effects of Cephalaria syriaca flour on physical, rheological and textural properties of sunn pest (Eurygaster integriceps) damaged wheat dough and bread
Başar, Şule; Karaoğlu, Mehmet Murat
The aim of this study was to investigate the effects of Cephalaria syriaca flour (CSF; 0.5, 1.0 and 1.5%) on the physical, textural and rheological characteristics of dough and bread obtained from sunn pest-damaged wheat (SPDW; 5, 10 and 15%). An increased CSF level significantly decreased the stickiness and volume loss values of dough and the firmness and chewiness values of bread for all SPDW levels. The dough stickiness and bread firmness values were considerably increased by the addition of SPDW at the 15% level (1.05 N and 29.76 N), whereas these values were reduced by the addition of 1.5% CSF (0.6439 N and 22.56 N). In general, the stress relaxation, gas retention and gluten extensibility parameters of dough; and the specific volume, colour, cohesiveness, springiness and resilience values of bread significantly increased depending on the increasing level of CSF. Especially, the 1.5% CSF level significantly improved the quality of the dough and breads. The results of the present study revealed that CSF addition to SPDW flour positively affected the stickiness, gas retention and stress relaxation of dough and the specific volume and instrumental textural properties of bread.
AtıfScopus13WoS10İncele - MakaleYalnız künye2021Scopus SJRQ2Double-exponential current-voltage (I-V) behavior of bilayer graphene-based Schottky diode
Kutluoǧlu, Esra Efil; Orhan, Elif Oz; Tataroǧlu, Adem; Bayram, Ozkan
Researches on layered materials such as graphene have attracted lots of attention recently. It has been shown that these materials have make a junction with many semiconductor materials that behave like Schottky diodes and have rectifying characteristics. The comprehension of its fabrication process and properties are a critical need toward graphene-based integrated electronics. The purpose of this study is to find out the current-voltage (I-V) performance of Bilayer Graphene (BLGr) based heterostructure fabricated on Al2O3/p-Si, and the effect of BLGr on diode parameters. Graphene has been grown on copper (Cu) foil by Chemical Vapor Deposition (CVD) method and transferred onto Al2O3/p-Si by using the polymethyl methacrylate (PMMA) wet transfer method. Raman analysis has been performed to obtain supportive information about CVD synthesized graphene film. The I-V plot of the diode exhibited two linear regions named Region 1 (0.08-0.19 V) and Region 2 (0.21-0.40 V). The double-exponential I-V behavior of the diode has been analyzed. The diode characteristics such as barrier height (ΦB0), series resistance (Rs), and ideality factor (n) have been calculated by using thermionic emission (TE), Norde, and Cheung methods. Especially, the values of the barrier height were compared with one another. It was found that they are in good agreement. Additionally, current conduction mechanisms of the diode were investigated using the forward bias ln(I) versus ln (V) plot. At lower and higher forward bias regions, the conduction mechanisms were determined as ohmic behavior and trap charge limiting current mechanism (TCLC), respectively.
AtıfScopus3WoS3OpenAlex4İncele - MakaleYalnız künye2021Scopus SJRQ1Frictionless contact mechanics of an orthotropic coating/isotropic substrate system
Öner, Erdal
This study has been performed to investigate the receding contact problem of a homogeneous orthotropic coating that is not bonded to a homogeneous isotropic substrate without any interfacial defects. The isotropic substrate is supported on a Winkler foundation. The problem is solved assuming that the contact between the rigid punch and orthotropic coating, and that between the orthotropic coating and isotropic substrate, are frictionless. Additionally, the effect of the body forces is neglected, and only compressive normal tractions can be transmitted through the interfaces. The contact analysis of the orthotropic coating, which is subjected to a contact load using a rigid cylindrical punch, is performed under plane strain conditions. The governing equations are analytically found using the theory of elasticity and Fourier integral transformation techniques. Subsequently, the governing equations are reduced to a system of two singular equations, wherein the unknowns are the contact stresses and contact widths. To numerically solve the resulting singular integral equations, Gauss-Chebyshev integration formulas are employed. It is analyzed the influence of the following parameters on the contact stresses and contact widths: orthotropic-material properties, punch radius, load ratio, Winkler foundation stiffness.
AtıfScopus26WoS26OpenAlex10İncele - MakaleYalnız künye2021Scopus SJRQ1Investigation of continuous and discontinuous contact cases in the contact mechanics of graded materials using analytical method and FEM
Yaylacı, Murat; Adıyaman, Gökhan; Öner, Erdal; Birinci, Ahmet
The aim of this paper was to examine the continuous and discontinuous contact problems between the functionally graded (FG) layer pressed with a uniformly distributed load and homogeneous half plane using an analytical method and FEM. The FG layer is made of non-homogeneous material with an isotropic stress–strain law with exponentially varying properties. It is assumed that the contact at the FG layer-half plane interface is frictionless, and only the normal tractions can be transmitted along the contacted regions. The body force of the FG layer is considered in the study. The FG layer was positioned on the homogeneous half plane without any bonds. Thus, if the external load was smaller than a certain critical value, the contact between the FG layer and half plane would be continuous. However, when the external load exceeded the critical value, there was a separation between the FG layer and half plane on the finite region, as discontinuous contact. Therefore, there have been some steps taken in this study. Firstly, an analytical solution for continuous and discontinuous contact cases of the problem has been realized using the theory of elasticity and Fourier integral transform techniques. Then, the problem modeled and two-dimensional analysis was carried out by using ANSYS package program based on FEM. Numerical results for initial separation distance and contact stress distributions between the FG layer and homogeneous half plane for continuous contact case; the start and end points of separation and contact stress distributions between the FG layer and homogeneous half plane for discontinuous contact case were provided for various dimensionless quantities including material inhomogeneity, distributed load width, the shear module ratio and load factor for both methods. The results obtained using FEM were compared with the results found using analytical formulation. It was found that the results obtained from analytical formulation were in perfect agreement with the FEM study.
AtıfScopus78WoS78OpenAlex21İncele - MakaleAçık Erişim2021Scopus SJRQ2Production of bread from doughs composed of high-pressure homogenisation treated flour slurries: effects on physicochemical, crumb grain and textural characteristics
Sert, Durmuş; Mercan, Emin; Tongur, Aymelek; Kara, Ümmügülsüm
This study aimed to investigate the physicochemical and textural characteristics of bread produced from doughs composed of high-pressure homogenization (HPH) treated flour slurries. For this purpose, bread samples were produced from doughs composed of HPH treated flour slurries at 0 (control), 20, 30, 50, and 70 MPa. HPH treatment resulted in decreased particle size with more uniformity in flour slurries. A monomodal particle size distribution was determined in slurries. HPH obtained higher firmness, consistency, and cohesivity in slurries. In bread samples, HPH increased yellowness and lightness values. The bread samples prepared from HPH treatment had 1.09–1.25 times higher specific volumes than the control sample. HPH treatment provided decreased hardness and increased cohesiveness and springiness values. Image analysis results showed HPH treatment decreased total cell count, whereas increased mean cell area of bread samples. The findings revealed that HPH treatment results in higher quality bread compared to control.
AtıfScopus5WoS5OpenAlex6İncele - MakaleAçık Erişim2021Scopus SJRQ2Experimental and Numerical Investigation of Levitation Force Parameters of Novel Multisurface Halbach HTS-PMG Arrangement for Superconducting Maglev System
Ozturk, Kemal; Badia-Majos, Antonio; Abdioglu, Murat; Dilek, Durukan Burak; Gedikli, Hasan
We have designed multisurface Halbach high temperature superconductor-permanent magnetic guideway (HTS-PMG) arrangements for magnetically levitated transportation (Maglev) and investigated the static force parameters in addition to the dynamic response characteristics. Three different Halbach HTS-PMG arrangements were used with multisurface (6 HTS, 4 HTS) and single surface (2 HTS) configurations and static and dynamic measurements were carried out in three different field cooling heights (FCHs). The bigger vertical loading capacity and wider loading gap were obtained with multisurface Halbach HTS-PMG arrangements. In addition, nearly four times bigger guidance force values of multisurface arrangements than that of single surface one indicates that the side HTSs in multisurface arrangements make a significant contribution to the guidance force and thus lateral movement stability of Maglev systems. Both the vertical and lateral dynamic stiffness values increased with decreasing FCH and it can be also said that the dynamic stiffness properties of Maglev systems can be enhanced especially in lateral direction by using the multisurface Halbach HTS-PMG arrangements. Understanding of these experimental observations is supported by dedicated theoretical modelling through a 2-D approximation of the system. We show that by using a single material parameter (the critical current density J_bf c) for the whole superconducting set, one may satisfactorily predict the complete series of experiments. The static and dynamic parameters obtained from this study and the results of dedicated theoretical modeling for single-surface and multisurface HTS-PMG arrangements are thought to be helpful for the researchers working on static and dynamic performances of HTS Maglev systems.
AtıfScopus28WoS22OpenAlex26İncele - MakaleYalnız künye2021Scopus SJRQ4Examination of the Effects of Archery Exercises on Some Physical Parameters of University Students
Türkmen, Mutlu; Kul, Murat; Gönen, Mevlüt; Karataş, İsmail; Ceyhan, Mehmet Ali; Yildirim, Ümit; Türker, Üstün; Ustabulut, Mete Yusuf
The aim of this study was to examine the effect of eight-week modern archery training on some physical parameters of university students. In the study, one-group pretest-posttest design from the experimental research methods was used. The study group consisted of a total of 25 voluntary- students were chosen randomly 10 female and 15 male, undergraduate, and graduate levels during the fall semester of 2020-2021 academic year at Bayburt University, who have not received Olympic archery training before. The Wilcoxon Signed Ranks Test was applied to analyse the data of the study. Regarding female participants, within the scope of Wilcoxon Signed Ranks Test results; according to the analysis results of the variables “Index Finger”, “Middle Finger”, “Ring Finger”, statistically significant differences were found between the pretest and posttest values for each variable. Regarding male participants, within the scope of Wilcoxon Signed Ranks Test results; according to the analysis of the results of the participants’ “Back-Leg”, “Index Finger”, “Middle Finger” variables, statistically significant differences were found between the pretest and posttest values for each variable.
AtıfScopus2WoS2OpenAlex2İncele - MakaleAçık Erişim2021Scopus SJRQ1Municipal solid waste-based district heating and electricity production: A case study
Tozlu, Alperen; Abusoglu, Aysegul; Ozahi, Emrah; Anvari-Moghaddam, Amjad
In this paper, municipal solid waste (MSW) based electricity production and district heating (DH) potential of Turkey are considered. Three MSW based waste-to-energy (WtE) scenarios is developed: (i) Scenario-I, a DH system integrated into a gas turbine power plant (GTPP), (ii) Scenario-II, a DH system integrated into an organic Rankine cycle (ORC), and (iii) Scenario-III, which is based solely on a DH system. As a result of the thermodynamic and thermoeconomic analyzes of these developed scenarios using an existing MSW-based cogeneration facility's actual operating data, the system with the most extended payback period (about 5 years) is found as the GTPP-DH system developed in Scenario-I, which also has the highest investment cost. On the other hand, the system with the shortest payback period (about 2 years) is found as the DH system developed in Scenario-III, which also has the lowest investment cost. Overall exergy efficiencies of the GTTP-DH, ORC-DH, and DH systems are found to be 41.86%, 16.15%, and 31.87%, respectively. When the developed WtE scenarios adapted to the pilot provinces selected from each geographical region of Turkey, it is found that the GTPP system developed in Scenario-I can increase the power generation capacity of MSW plants for each province by about 20%.
AtıfScopus16WoS15OpenAlex16İncele - MakaleAçık Erişim2021Scopus SJRQ1Pb (II) biosorption from the aqueous solutions by raw and modified tea factory waste (TFW)
Nuhoğlu, Y.; Ekmekyapar Kul, Z.; Kul, S.; Nuhoğlu, Ç.; Ekmekyapar Torun, F.
The study is aimed to determine Pb (II) biosorption from synthetic wastewaters using natural and modified tea factory waste as biosorbent material. This process is carried out with this waste matter, which is found in large quantities, so cheap and has high metal adsorption ability. The sorption kinetic studies were determined as variations of initial pH value, particle size, initial Pb (II) and tea factory waste concentrations, stirring speed and temperature. Biosorption reached the equilibrium in 15 min. Zeta potential values of the biosorbent were defined in the range of pH 2 to 4. The adsorption isotherm models give the experimental values, and the thermodynamic characteristics of the patterns generally give insight about the sorption mechanism depending on the surface characteristics and affinity of the biosorbent. The biosorption mechanism was searched considering to Freundlich, Langmuir, BET and Temkin isotherm model, and the experimental adsorption values were conformed to Freundlich adsorption model. The optimum experimental conditions were investigated as pH 3.5, particle size of 0.125–0.25 mm, stirring speed of 200 rpm, biosorbent concentration of 7 g L−1 and 25 °C. In these conditions, the highest efficiency of biosorption was obtained as 94.07% and after the activating process the efficiency was reached to 97.73% at 70 mg L−1. The maximum Pb (II) removal capacity of raw tea factory waste was found to be 22.111 mg g−1 at 200 mg L−1. The biosorption kinetics has complied with the pseudo-second-order model. Thermodynamic studies stated that this biosorption phenomenon was an endothermic process.
AtıfScopus26WoS26OpenAlex27İncele - MakaleYalnız künye2021Scopus SJRQ1Learning trajectory of a student with learning disabilities for the concept of length: A teaching experiment
Güven Akdeniz, Dilşad; Argün, Ziya
This study aims to map the learning trajectory (LT) of a student with learning disabilities (LDs) regarding the unit concept in length measurement and the usage of rulers. The article draws on data from a teaching experiment with a 10-year-old student with LDs in Turkey. Data were analyzed in two stages, including microanalysis, where each successive teaching session was separately analyzed, and macroanalysis, where the teaching sessions regarding interrelated instructional goals were analyzed to construct the LT. The main findings of the study illustrate that this student with LDs eliminated her misconceptions about the unit concept and using a ruler, accomplished the determined instructional goals to a large extent, and reached a higher level of thinking with a 4-month teaching experiment designed based on her specific developmental capacity.
AtıfScopus9WoS2OpenAlex8İncele - MakaleYalnız künye2021Scopus SJRQ1Assessment of different solution methods for receding contact problems in functionally graded layered mediums
Yaylacı, Murat; Eyüboğlu, Ayşegül; Adıyaman, Gökhan; Yaylacı, Ecren Uzun; Öner, Erdal; Birinci, Ahmet
This paper presents a comparative study of different methods, such as the analytical method, finite element method (FEM), and multilayer perceptron (MLP) for analyzing a frictionless receding contact problem. The problem consists of two layers resting on a Winkler foundation. The top layer is functionally graded (FG) along the depth and pressed using a rigid cylindrical stamp, whereas the bottom layer is homogeneous. We assumed that the contact between the two layers, and that between the FG layer and the rigid cylindrical stamp are frictionless; additionally, compressive normal tractions can be transmitted through the interface. First, the problem was solved analytically using the theory of elasticity and integral transform techniques. Second, the finite element solution of the problem was obtained using ANSYS software. Finally, the problem was extended based on the MLP, which an artificial neural network used for different problem parameters. The results of this study showed that the variations in the contact lengths at the interface between the rigid cylindrical stamp and the FG layer, those between the homogeneous layer and the FG layer, and the maximum contact pressures at these interfaces depended on various dimensionless quantities such as the stamp radius, stiffness parameter, shear modulus ratio, and elastic spring constant ratio. We observed that the results obtained with the three different methods, namely the analytical method, FEM, and MLP, are extremely compatible with each other, thus proving the accuracy of these results.
AtıfScopus87WoS86OpenAlex40İncele - MakaleAçık Erişim2021Scopus SJRQ2A surveying of photon and particle radiation interaction characteristics of some perovskite materials
Şakar, Erdem; Alim, Bünyamin; Fırat Özpolat, Özgür; Ceviz Şakar, Betül; Baltakesmez, Ali; Akbaba, Uğur
In this study, we aimed to determinate of the photon and particle radiation interaction parameters of six different perovskites to help use perovskite materials in radiation applications. The parameters that are aimed to be investigated are MAC, HVL, MFP, Zeff, Neff, Ceff and EBF for photons, range values for charged particles, and FNRCS values for neutrons. The photon-interaction parameters the FNRCS values of the perovskites were calculated using Phy-X/PSD software in the energy range of 1 keV–100 GeV for photons and at 4.5 MeV energy for neutrons, respectively. Moreover, the range values of the perovskites were calculated using SRIM Monte Carlo software (for H+ and He++ particles) and ESTAR NIST software (for electrons) in the energy range from 0.01 MeV to 20 MeV. In order to make a notable assessment about the radiation interaction possibilities of the perovskites, the results obtained were compared with some standard shielding materials. According to the results obtained for all radiation types examined, it was determined that all calculated parameters were strongly dependent on both the type and energy of the radiation and the type of material. Additionally, it was observed that the order of preference of the examined materials as armor material in radiation applications varies according to the radiation type and energy. Consequently, it was determined that while the most suitable material in terms of photon shielding is P6 (Cs2SnI6) inorganic perovskite among the perovskites examined, this sample is not suitable material for neutron shielding applications.
AtıfScopus27WoS25OpenAlex26İncele - MakaleYalnız künye2021Scopus SJRQ1Students’ Well-Being and Academic Achievement: A Meta-Analysis Study
Kaya, Metin; Erdem, Cahit
A considerable amount of literature has been published on students’ well-being, but empirical research has yielded ambiguous results regarding the relationship between well-being and academic achievement. Meta-analysis studies on this issue are scarce, and the available studies focus on a single domain of well-being. Meta-analyses investigating students’ general well-being and academic achievement are needed. To this end, we carried out a meta-analysis study on the association between students’ general well-being and academic achievement based on data from correlational studies involving 54,426 participants in 81 independent samples. We report a significant and positive but small effect size based on this dataset. The effect sizes differ significantly in terms of the moderator variables of publication year, age, school level, and publication type, while the correlation is robust across well-being domains, academic areas, scale types, and development levels of countries. Results are discussed and implications are suggested in line with the literature.
AtıfScopus200WoS158OpenAlex225İncele - MakaleAçık Erişim2021Scopus SJRQ1Synthesis and characterization of cellobiose-derived oligosaccharides with Bifidogenic activity by glucansucrase E81
İspirli, Hümeyra; Bowman, Michael J.; Skory, Christopher D.; Dertli, Enes
Cellobiose-derived oligosaccharides were produced from acceptor reactions with glucansucrase E81 and their prebiotic potentials were determined in this study. The major product was a mixture of trisaccharides formed by the addition of an α-linked glucose to cellobiose at either the 2-O position of the reducing end (86%) glucose or the 6-O position of the non-reducing end glucose (11%) demonstrated by NMR spectroscopy and LC-MS-LTQ analysis. The purified DP 3 cellobiose-derived oligosaccharides were then tested for in vitro human gastric juice and α-amylase digestion and no digestion was observed during the 6 h digestion period. Importantly, DP 3 cellobiose-derived oligosaccharides promoted the growth of Bifidobacteria at high levels demonstrating a Bifidogenic effect and a mild level of proliferation was observed for Lactobacilli suggesting the prebiotic roles of cellobiose-derived oligosaccharides.
AtıfScopus7WoS5OpenAlex6İncele - MakaleAçık Erişim2021Scopus SJRQ1Thermoeconomic analysis of a hybrid cogeneration plant with use of near-surface geothermal sources in Turkey
Tozlu, Alperen; Gençaslan, Betül; Özcan, Hasan
In this study, thermodynamic and thermoeconomic analyses of systems that produce electricity and heat through the use and storage of solar energy and near-surface geothermal sources are carried out. Three different configurations, which are the organic Rankine cycle (ORC), cogeneration system (CGN) and hybrid system (HYB), are coupled to the parabolic trough collector (PTC) system. The systems are named PTC-ORC, PTC-CGN and PTC-HYB are conducted. The reference system called PTC-ORC only produces electrical energy with parabolic trough collectors and it does not have a thermal energy storage system, whereas in PTC-CGN, in addition to the cogeneration of electricity and heat, thermal energy storage is also available. Finally, thermodynamic and economic analyses are conducted in the PTC-HYB with the assistance of near-surface geothermal energy, which is widely available in Turkey. In this study, the actual data of Ankara Kızılcahamam near-surface geothermal fields are taken as the heat source for the hybrid system. These facilities, each producing 1 MW of electricity, are first optimized with the help of parametric studies, and exergoeconomic analysis is performed with respect to optimum thermal conditions. The electricity production costs of PTC-ORC, PTC-CGN and PTC-HYB are found to be 0.257 $/kWh, 0.448 $/kWh and 0.401 $/kWh, respectively. The study demonstrates that thermal energy storage brings extra costs, while near-surface geothermal sources may help decrease energy costs from renewables.
AtıfScopus15WoS13OpenAlex21İncele - MakaleAçık Erişim2021Scopus SJRQ3Comparing of the Magnetic Force Parameters of Superconducting Maglev System Using Horizontal and Vertical PMG Geometry in Multi-Surface HTS-PMG Arrangement
Ozturk, Kemal; Savaskan, Burcu; Abdioglu, Murat; Cansiz, Ahmet; Dilek, Durukan Burak; Karaahmet, Zekeriya
In this study, a detailed static and dynamic experimental studies were carried out in different cooling heights (CH) by using two different multi-surface HTS-PMG arrangements with horizontal (MS-H) and vertical (MS-V) geometries to determine the optimum magnetic force, static stiffness, dynamic response, and dynamic stiffness parameters of superconducting Maglev system. The maximum levitation force values (in CH = 25 mm) were obtained as 202 N and 84 N, respectively, with horizontal and vertical geometry HTS-PMG arrangements, while the maximum guidance force values (in CH = 5 mm) were obtained as −58 N and −22 N, respectively. Also, the vertical static (in CH = 25 mm) and dynamic stiffness (in CH = 5 mm) values were determined as 33.8 N/mm and 37.8 N/mm, respectively, for MS-H and 12.3 N/mm and 25.1 N/mm, respectively, for MS-V arrangements. The bigger levitation force, guidance force, and both static and dynamic magnetic stiffness values of MS-H arrangement with horizontal geometry than that of MS-V arrangement with vertical geometry indicate that the horizontal HTS-PMG geometry is more suitable for practical Maglev applications in terms of loading capacity and movement stability.
AtıfScopus5WoS4OpenAlex4İncele - MakaleAçık Erişim2021Scopus SJRQ1New formalism for characterization of simple non-reciprocal networks free from singularity-point problem
Hasar, Ugur Cem; Kaya, Yunus; Ozturk, Gokhan; Ozturk, Hamdullah; Izginli, Mucahit; Ertugrul, Mehmet
A method has been proposed for accurate characterization of non-reciprocal networks without enforcing the passivity principle. Thanks to the introduced different even and odd coefficients, our method has no singularity-point problem as compared with the conventional method. The proposed method is validated by scattering parameter measurements of a ferrite-loaded waveguide shifter. In addition, it is demonstrated by measurements that our method, as compared with the conventional one, is more resistant to random noise due to post-calibration effects.
AtıfScopus1WoS1OpenAlex1İncele - MakaleAçık Erişim2021Scopus SJRQ1A comparative thermoeconomic analysis and optimization of two different combined cycles by utilizing waste heat source of an MSWPP
Ozahi, Emrah; Abusoglu, Aysegul; Tozlu, Alperen
In this paper, thermodynamic and thermoeconomic analysis as well as genetic algorithm optimization of two combined cycles, a gas turbine-organic Rankine cycle (GT-ORC) and a gas turbine-Kalina cycle (GT-KAL) are carried out. The novelty of this study is that the cycles are adapted to an actual solid waste power plant to generate additional power from the exhaust gas. Thus, the power generation capacity of the actual power plant can be raised by using the combined cycle. Due to this reason, besides the thermodynamic analysis of the cycles, thermoeconomic analyses and optimizations are also very important in order to improve the actual system capacity. The net power output of GT-ORC and GT-KAL are found to be 1.51 MW and 1.59 MW, respectively. The results obtained are seen to be reasonable when compared to the net power output of the power plant (5.66 MW). Another originality of this study is that the thermoeconomic results are improved by utilizing a multi-objective optimization method namely non-dominated sorting genetic algorithm method (NSGA-II). Thus, the two objectives, total power output and the total cost rate, at the design stage of the cycles are optimized and enhanced. Due to the optimization results, it is found that the net power output of the GT-ORC and GT-KAL are increased by 11.34% and 0.99%, respectively, while the total cost rates are decreased by 18.59% and 1.31%, respectively. GT-ORC with the net power output of 1.70 MW is seen to be more efficient as compared to GT-KAL which produces a net power output of 1.61 MW. However, the total and the capital cost rates of GT-ORC are found to be higher than those of GT-KAL.
AtıfScopus7WoS5OpenAlex11İncele