Sürdürülebilir Kalkınma Amaçları

Yazarlar

  • MakaleYalnız künye2023Scopus SJRQ1
    Hydrodynamic performance evaluation of screening on the physical unit operations in wastewater treatment based on experimentally validated CFD computations

    Şahin, Nagehan; Şibil, Rahim

    This paper introduces an evaluation of the hydrodynamic performance of the flow in the screens used on the physical unit operations in a selected full-scale wastewater treatment plant (WWTP) based on Computational Fluid Dynamics (CFD) simulations. The numerical study was carried out with the ANSYS Fluent, CFD software by using the three-dimensional (3 D), steady, incompressible flow based on the Reynolds-Average Navier-Stokes equations with three different turbulence modeling. The hydrodynamic behavior of the screening facility, combined with head pond-upstream channel-bar screens was evaluated under different conditions of the mass flow rate and velocity fields. Also, the numerical study was validated against the experimental study, which implemented in-situ measurements by Acoustic Doppler Velocimeter (ADV), and consistent results were obtained between the numerical and experimental study. Interestingly, while the Realizable (real) k-ε turbulence model with the relative error of 9.31% gave the best predicting results in the head pond, the renormalization group (RNG) k-ɛ turbulence model with the relative error of 9.05% gave the best predicting results in the upstream channel and through bar screens. As a result of the experimental measurements and CFD analyses carried out in the full-scale WWTP, the function of the screening facility was found to be incomplete. Moreover, a hydraulically improved new geometry was presented to operate the existing WWTP efficiently.

    • SDG 6 · Temiz Su ve Sanitasyon
    AtıfScopus16WoS10OpenAlex15
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  • MakaleYalnız künye2023Scopus SJRQ1
    Microwave decontamination processing of tahini and process design considerations using a computational approach

    Topcam, Huseyin; Coskun, Eda; Son, Ezgi; Kutuk, Dilay; Aytac, S. Aykut; Mert, Behic; Ozturk, Samet; Erdogdu, Ferruh

    Tahini, as a low moisture food product, is linked to several outbreaks of Salmonella recently even though a high temperature roasting (of sesame seeds) through its production is involved. Therefore, a final decontamination approach might be required for safety. Considering its higher oil content and lower thermophysical properties, conventional approaches are not easy to apply while preserving the quality attributes. Therefore, microwave heating was used for decontamination purpose. For this purpose, a computational mathematical model was developed first to determine the temperature distribution of tahini during microwave heating, and microbial inactivation studies for Salmonella enteritidis (ATCC 13076) were carried out. Changes in color and peroxide values were evaluated, and the experimentally validated model was further used to design an industrial process to achieve a 5-log cycle reduction as an efficient decontamination processing. The target temperature over 80 °C within the sample was demonstrated to achieve such a process, and industrial scale process conditions were presented for 262 kg/h process capacity.

    • SDG 2 · Açlığa Son
    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus9WoS7OpenAlex10
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  • BildiriYalnız künye2023
    A Hybrid CNN-LSTM Framework for Unsupervised Anomaly Detection in Water Distribution Plant

    Sahin, Ali Kivanc; Cavdar, Bora; Dogan, Ramazan Ozgur; Ayas, Selen; Ozgenc, Busra; Ayas, Mustafa Sinasi

    To reduce potential threats to public health and economic losses, water distribution systems, which are critical parts of industrial control systems, require accurate and effective anomaly detection. The successful incorporation of machine learning models into anomaly detection procedures has been made possible by recent developments in computer science. In this research, a hybrid CNN-LSTM framework for anomaly detection in water distribution systems is presented using Python programming language in the JupyterLab environment. The performance of the proposed CNN-LSTM network model is carefully evaluated on the publicly available WADI dataset, which contains several types of attacks for a water distribution testbed, using a statistical window-based anomaly detection approach. The experimental results show acceptable precision, recall and F1 scores of 0.8619, 0.7041, and 0.775, respectively, demonstrating the efficiency of the framework in detecting anomalies in the water distribution system.

    • SDG 6 · Temiz Su ve Sanitasyon
    AtıfScopus13OpenAlex12
    Scopusİncele
  • MakaleYalnız künye2023Scopus SJRQ2
    Determination of shear behavior of magneto-rheological elastomers under harmonic loading

    Mazlum, Ugur; Celik, Ilhan

    Magneto-rheological (MR) materials can respond reversibly and quickly under the effect of an external magnetic field. MR materials contain micron-sized iron particles. These iron particles are typically dispersed in an elastomer or a liquid. These materials due to their properties constitute a kind of smart material in terms of engineering material. Such materials are used as isolators in various engineering applications, structures, and sound control subsystems. This study aimed to determine the mechanical properties for shear behavior of MR materials for under harmonic loading. Parameters such as matrix materials with different hardness values, powder types, magnetic field, frequency, and deformation were studied. The parameters related to the MR material itself were analyzed with the obtained data. The present study reveals that considering the sensitivity to magnetic field parameter, composite materials having the most suitable properties were produced with Shore 2 hardness value and SQ magnetic powder. It had been observed on increase about 200% at the rate of Shore A10 and A2 as a result of comparing the hardness scale. Also according to the powder rate while there was an increase on worth effect of relative MR, it is seen that the biggest increase had been in SQ powder with 199% worth. When looked some studies in literature, about comparing different hardness values such as matrix materials powder types etc. there aren’t any studies. The state of magnetic field thinks that features such as MR effect, Storage, and Loss modulus haven’t been examined yet.

    AtıfScopus3OpenAlex3
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  • MakaleYalnız künye2023Scopus SJRQ1
    Optimum tuned tandem mass dampers for suppressing seismic-induced vibrations considering soil-structure interaction

    Araz, Onur; Noroozinejad Farsangi, Ehsan

    In recent studies, it has been stated that tuned tandem mass dampers (TTMD) will be a practical mechanical solution to reduce the dynamic responses of structures under seismic excitations. However, since TTMD is tuned based on the dominant frequency of the superstructure, ignoring the soil-structure interaction (SSI), it may cause a notable deterioration in the control performance of the control devices. Thus, a methodology for the optimum design of TTMD positioned on the top story of a high-rise building due to near-fault pulse-like ground motions considering potential SSI effects has been investigated in this paper. Firstly, the TTMD is located on the top story of a well-known 40-story shear building, and the equations of motion for soil-structure-TTMD interaction are derived. Based on the sequential quadratic programming (SQP), the tuning parameters of TTMD are then found for different support conditions in the frequency domain. The efficiency of SQP is also compared with two meta-heuristic algorithms (i.e., simulated annealing and pattern search algorithms). The effectiveness of optimum TTMD is tested using 30 near-fault pulse-like ground motions using time-domain analyses. Numerical results showed that the optimum TTMD is more effective in suppressing the maximum displacement and inter-story drift of the building, considering SSI. It is also found that the frequency content of the earthquake, as well as the pulse period of the earthquake and soil type, has a significant effect on the control performance of the TTMD.

    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    • SDG 11 · Sürdürülebilir Şehirler ve Topluluklar
    AtıfScopus35WoS36OpenAlex34
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2023Scopus SJRQ2
    Tor topography in Giresun mountains, Türkiye

    Uzun, Ali; Aylar, Faruk; Zeybek, Halil İbrahim; Alemdağ, Selçuk

    Tors are mound-like rock landforms, resistant to erosion, that may sometimes reach the size of several storeys of house by volume. They may develop in different climate regions and different rock types, led by granitic rocks. In this study, tors developed in granitic rocks around Yaylalı village linked to Kürtün county in Gümüşhane were investigated. The study area is located in the eastern part of the Giresun mountain range in northeastern Turkey, 2000–2300 m above sea level. The aim of the study is to determine the natural environmental characteristics in tor formation and to reveal the effect of bedrock on tor formation. During field studies, 18 tors were selected by noting location, size and structural features, and dimensions were measured. Thin sections were first made from the rock samples taken from the tors and then the mineralogical composition was investigated by modal analysis method. As a result of this analysis, it was determined that the bedrock forming the tors is granite. During the field observations, it was determined that the intersecting vertical joints supported the formation of castle-like tors, while the horizontal joints supported the formation of pita pile-shaped tors. There are also pseudokarstic shapes resembling kamenitza and karst pavement. In conclusion, joint sets causing local resistance differences directed the formation of tors, while excess slope affected surface erosion and suitability of climate conditions-controlled weathering rate.

    AtıfScopus1WoS1OpenAlex3
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  • MakaleYayıncıda açık erişim2023Scopus SJRQ4
    Comparison of online and face-to-face exams conducted in Physics I course in higher education

    Ural, Mustafa Nuri; Takaoğlu, Zeynep Başkan

    The coronavirus pandemic has affected most fields, including education, and most lessons have had to be conducted as distance education. In this study, it is aimed to compare student success in face-to-face exams with that in distance exams in the Physics I course. The sample consisted of 167 students who took a multiple-choice exam in distance education in the 2020-2021 academic year and 155 students who took the multiple-choice exam in face-to-face education in the 2019-2020 academic year. In the first phase of the study, the questions asked in both types of exams were classified according to Bloom’s taxonomy, and then descriptive and comparative statistics were used. As a result, according to Bloom’s taxonomy, the majority of the questions asked were at the application level. In the statistical analysis, it was determined that the averages of both groups were close to 45 out of 100, and there was no significant difference between the group averages as a result of the t-test. Accordingly, it has been concluded that the use of online exams during the pandemic as an alternative to face-toface exams in normal processes will not make a significant difference.

    • SDG 4 · Nitelikli Eğitim
    AtıfScopus2OpenAlex3
    ScopusTR Dizinİncele
  • MakaleYalnız künye2023Scopus SJRQ1
    Correlation coefficients of simplified neutrosophic multiplicative sets and their applications in clustering analysis

    Köseoğlu, Ali; Şahin, Rıdvan

    The use of fuzzy sets, intuitionistic fuzzy sets and neutrosophic sets can often handle with real-life problems that contain incomplete and uncertain information. The 0–1 scale is used to deal with such information which is graded symmetrically and uniformly but, some problems consist of unsymmetrical and non-uniform information. Although intuitionistic multiplicative set (IMS) is a powerful tool to deal with this kind of problems, due to the dependence of hesitant information to the membership and non-membership functions in IMS, it brings a restriction to decision-makers while working on the real-life problems such as applications of correlation coefficients and clustering. In this study, we propose novel correlation coefficients (CCs) of simplified neutrosophic multiplicative sets (SNMSs) which is defined recently by removing the shortages of IMSs. Firstly, we give SNMS-based operations, fulfil the deficiencies in the theoretical background of IMS and establish a theoretical structure for the SNMS. Then, we propose novel correlation coefficients (CC) of SNMS and show some of their important properties. Finally, we apply the CCs to a clustering problem to confirm the efficiency of the proposed SNMS and its correlation coefficients.

    AtıfScopus5WoS4OpenAlex6
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  • MakaleYayıncıda açık erişim2023Scopus SJRQ3
    Chemical Content and Antimicrobial Activities of Essential Oils Obtained from Plant Parts of Juniperus excelsa M. Bieb.; [Kemijski sastav i antimikrobno djelovanje eteričnih ulja dobivenih iz dijelova biljke Juniperus excelsa M. Bieb.]

    Saruhan, Emrah; Öz, Mehmet

    This study was conducted to determine the chemical content, antibacterial, and antifungal properties of essential oil obtained from the parts of the plant called Juniperus excelsa M. Bieb. In this study, essential oils of cone, needle, and twig of J. excelsa plant, which is a naturally grown plant in Gümüşhane province, were obtained by hydrodistillation method in a Clevenger type device. Chemical composition of essential oils was determined thanks to the analysis conducted with GC-MS/FID device. Besides, antimicrobial activity tests of essential oils were decided in contrast to 23 different microorganisms with the disc diffusion method. As a result of the essential oil analysis of J. excelsa, the percentage of essential oil yield in cones, needles, and twigs was found as 5.88 %, 2.00 %, and 0.62 %, respectively. α-pinene was confirmed to be the most abundant main compound found in the essential oils of cones, needles, and twigs. As a result of the essential oil analysis of the cone, needle, and twig of J. excelsa species, it was revealed that monoterpenes were the most abundant chemical class in terms of percentage. In the antimicrobial activity test performed on the essential oils of J. excelsa plant parts, it was found that cones, needles, and twigs have a strong antimicrobial effect against Bacillus subtilis, Enterococcus faecalis, Escherichia coli, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella enteritidis, Salmonella typhimurium, Staphylococcus aureus, Candida albicans, Penicillum expansum, Saccharomyces cerevisiae bacteria, yeast, and molds.

    AtıfScopus3WoS2OpenAlex1
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  • MakaleYalnız künye2023Scopus SJRQ2
    Trend analysis of precipitation using innovative approaches in northwestern Turkey

    Körük, Ali Emre; Kankal, Murat; Yıldız, Mehmet Berkant; Akçay, Fatma; Şan, Murat; Nacar, Sinan

    Precipitation is highly sensitive to climate change, and monitoring its trends over time is essential for understanding the effects of global warming on the Earth's water cycle. This study investigates the effects of climate change on monthly precipitation in the Susurluk Basin located in northwestern Turkey, using innovative trend analysis methods. Innovative Polygon Trend Analysis (IPTA) using star graphics and Improved Visualization for Innovative Trend Analysis (IV-ITA) techniques were used to analyze precipitation data from nine stations in the basin over 50 years (1970–2019), and the findings were compared to classical Mann-Kendall (MK) results. According to the trend analysis results, the MK method detected significant trends in only two months in the decreasing direction. In these decreasing trends observed at Simav and Keles stations in November, z values were calculated as −2.38 and −2.05, respectively. IPTA method detected increasing trends in 54 months and decreasing trends in 40 months; this means there is a change of more than 5% between two half series. The IV-ITA method indicated an increase of more than 40% in the low values for January, March, August, and September. In addition, there was an increasing trend of more than 40% in the high values observed in September at all stations. It was observed that mean precipitation heights increased from September to December and then decreased throughout the basin. It is predicted that decreases in precipitation during dry seasons may put intense pressure on agricultural water use and affect water quality. In addition, the increase in precipitation in spring months may increase flood events. It was determined that graphical innovative trend analysis methods are more effective in trend identification than MK, and these methods' results have much higher visual inspection and linguistic interpretation possibilities. Innovative methods allow for more flexible and in-depth analysis using different statistical parameters.

    • SDG 6 · Temiz Su ve Sanitasyon
    • SDG 13 · İklim Eylemi
    AtıfScopus40WoS34OpenAlex43
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  • MakaleYayıncıda açık erişim2023Scopus SJRQ1
    DEVELOPMENT OF THE THIRST DISCOMFORT SCALE: A VALIDITY AND RELIABILITY STUDY

    Çiftçi, Bahar; Yıldız, Güzel Nur; Avşar, Gülçin; Köse, Sema; Aydın, Esra; Doǧan, Sevgi; Çelik, Şeymanur

    Background Thirst is a sensation associated with a dry mouth and the desire or craving to drink water. Surgical patients are among those hospitalized individuals who are at high risk of developing both osmotic and hypovo-lemic thirst. Objectives To develop a new measurement tool for evaluating the thirst-related discomfort of surgical patients and to assess its validity and reliability. Methods The study population consisted of patients admitted to the surgical clinics of a research hospital in Turkey between January and March 2022. The new measurement tool was developed in several stages: a pilot implementation phase with 51 patients and the main implementation phase with 198 patients. Data were col-lected by means of face-to-face interviews with patients. Exploratory factor and confirmatory factor analyses were performed using IBM SPSS Statistics, version 22, and IBM SPSS Amos. Results The final Thirst Discomfort Scale consisted of 12 items in 3 subdimensions. The Cronbach α values of the scale subdimensions ranged from 0.787 to 0.848, and the Cronbach α value for the scale as a whole was 0.886. The scale explained 66.237% of the total variance of the data. Conclusion The Thirst Discomfort Scale consisting of 12 items and 3 subdimensions is a valid and reliable measurement tool for evaluating thirst-related discomfort of surgical patients.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus8WoS10OpenAlex11
    ScopusWeb of SciencePubMedİncele
  • MakaleYalnız künye2023Scopus SJRQ1
    Investigating the environmental Kuznets curve hypothesis with recovered paper consumption, human development index, urbanization, and forest footprint

    Aydin, M.; Koc, P.; Tumay, M.

    The aim of this study, which covers the period from 1991 to 2017, is to analyze the relationships between recovered paper consumption, human development index, urbanization rate, and forest footprint in the framework of the Environmental Kuznets Curve (EKC) hypothesis in the 10 countries that consume the most recovered paper. Considering that wood is the raw material of paper, the study investigates whether the increase in the consumption of recovered paper has a positive effect on the forest footprint. Therefore, unlike other studies, the dependent variable of the EKC model is the forest footprint. The study is original in that it is the first to analyze the effects of recovered paper consumption on environmental degradation in the context of the EKC hypothesis. To analyze the relationships between the variables, we use panel cointegration tests based on AMG and CCE estimators, which allow analysis on both a country and group basis. According to the results, the EKC hypothesis is valid only in the Netherlands. While there is a statistically significant and negative relationship between recovered paper consumption and forest footprint in the Netherlands, there is a statistically significant and negative relationship between urbanization and forest footprint in Italy. Economic and ecological benefits and costs must be considered to measure the net benefit of waste management programs. In addition, to analyze how environmental impacts change over time, ecological footprint and gas emissions during waste generation or disposal should be measured similarly to carbon emissions.

    • SDG 12 · Sorumlu Üretim ve Tüketim
    • SDG 13 · İklim Eylemi
    • SDG 15 · Karasal Yaşam
    AtıfScopus14WoS14OpenAlex16
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  • MakaleYalnız künye2023Scopus SJRQ3
    A Numerical Study to Evaluate the Changes in Dynamic Properties of Various Steel Truss Types Under Fire Conditions

    Sibil, R.; Ozyurt, E.

    This study numerically examines the changes in dynamic properties of fire-damaged steel trusses made of square hollow sections subjected to uniform and non-uniform heating scenarios. After verifying the numerical models at both ambient and elevated temperatures, a vast number of the simulations were analysed using non-linear finite element software to evaluate the effects of fire scenarios, truss types, and fire-damaged levels on the fire dynamic characteristics of square hollow section Warren, Howe, and Pratt trusses. The results indicated that the natural frequency of steel trusses significantly decreased as the fire-damaged level increased. In the case of local fire, the natural frequencies of the trusses began to drop suddenly at temperatures above 550 °C. Whereas the drop in the natural frequency of the uniformly heated trusses started at even much lower temperature levels. Moreover, the decrease in the natural fundamental frequencies of the uniformly heated trusses was lower than the reduction rate of the modulus of elasticity at high temperatures due to the large non-linear deformations. Since the modification of the stiffness of the truss by simply the reduction factor of the elastic modulus of the steel may be inappropriate to calculate the fundamental frequency of the trusses in the local and global fires, a new method was introduced to calculate the fundamental frequency value of the steel trusses in the fire.

    AtıfScopus7WoS5OpenAlex6
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  • MakaleYalnız künye2023Scopus SJRQ1
    Examining the role of urban-industrial symbiosis in the circular economy: an approach based on N-Force field theory of change and N-ISM-Micmac

    Erol, Ismail; Peker, Iskender; Ar, Ilker Murat; Searcy, Cory

    The circular economy (CE) refers to a new industrial paradigm that contrasts with the linear supply chain structure based on a "take, make, use, dispose" pathway. Due to its potential contributions to improving the CE, industrial symbiosis (IS) has been recognized as a feasible way to advance it. Urban symbiosis is an extension of IS that involves a series of symbiotic relationships among enterprises within the urban area. Combining urban and industrial symbiosis (Ur-IS) is a step toward better resource efficiency in urban areas and industrial zones and urban areas. However, while there are several driving forces for Ur-IS adoption, there are also many inhibiting factors. A comprehensive decision framework is needed to address the principal drivers and challenges for Ur-IS initiatives. Türkiye, designated as a candidate for full EU membership in 1999, also places importance on environmental sustainability goals and effective resource management in its own move towards a CE. Our literature review concluded that there is only one quantitative study investigating the driving and (or) restraining forces for Ur-IS adoption in emerging and industrialized countries. The main purpose of this study is to investigate the potential of Ur-IS implementation in Türkiye through the proposed Neutrosphopic-Simple Additive Weighting Method-based force field theory of change and the Neutrosphopic–Interpretive Structured Modeling-Cross-Impact Matrix Multiplication Method. The findings suggest that lack of policies, lack of incentives and regulations, and vulnerability and supply uncertainty are the most significant restraining forces for Ur-IS implementation in Türkiye. The research findings can assist decision-makers in Türkiye in effectively implementing Ur-IS.

    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    • SDG 11 · Sürdürülebilir Şehirler ve Topluluklar
    • SDG 12 · Sorumlu Üretim ve Tüketim
    AtıfScopus9WoS8OpenAlex9
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2023Scopus SJRQ4
    Effect of detector crystal size on Compton suppression factors

    Kaya, Selim; Çelik, Necati; Gök, Abdulkadir; Çevik, Uğur

    The geometrical parameters which affect the suppression factor for an HPGe (High Purity Germanium)-NaI Compton suppression spectrometer were studied by a Monte Carlo simulation with the EGS4 system. The spectrums were crated for 5 energy values ranging from 200 keV to 2 MeV. Compton suppression factors (CSFs), the parameters characterizing the system performance, were calculated for different HPGe crystal parameters. It was observed that to obtain better Compton suppressed factors, a laboratory must choose as small HPGe crystal as possible for energy values up to 400 keV. However, for higher energies up to 2 MeV, larger HPGe crystals provide better Compton suppression systems. These findings suggest that the choice of HPGe crystal size can significantly impact the performance of a Compton suppression spectrometer and should be carefully considered in its design and optimization.

    AtıfScopus5WoS4OpenAlex6
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  • MakaleYalnız künye2023Scopus SJRQ1
    Immunogenic evaluation of multi-epitope peptide-loaded PCPP microparticles as a vaccine candidate against Toxoplasma Gondii

    Yilmaz-Ozturk, Rabia; Calik, Hilal; Yaman, Serkan; Ustun-Karatop, Eslin; Cakir-Koc, Rabia

    Toxoplasmosis is a major health problem and socioeconomic burden, affecting around 30–50% of the global population. Poly(dicarboxylatophenoxy)phosphazene (PCPP) polymer was chosen as adjuvant for the immunogenic peptide antigen. Peptide-loaded PCPP microparticles were synthesized via the coacervation method and the characterization studies of microparticles were conducted to determine their size, charge, morphology, encapsulation efficacy, and loading capacity. To evaluate in vivo efficacy of the vaccine candidate, Balb/c mice were immunized with the formulations. Brain and spleen tissues were isolated from animals to investigate cytokine levels, lymphocyte proliferation, and brain cyst formation. As a result, antibody and cytokine responses in groups immunized with peptide-loaded PCPP microparticles were found to be significantly higher when compared to the control group. In conclusion, our novel multi-epitope peptide-loaded PCPP microparticle-based vaccine formulation demonstrated considerable humoral and cellular immune responses against T. gondii and protected mice against T. gondii infection during Toxoplasmosis.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus3WoS2OpenAlex3
    ScopusWeb of SciencePubMedİncele
  • MakaleYalnız künye2023Scopus SJRQ2
    The effect of fabrication method on physical properties of different Y211 and 20% Ag2O added YBCO sample

    Duman, Şeyda; Çakır, Bakiye; Başoğlu, Mehmet; Küçükömeroğlu, Tayfur; Aydıner, Alev

    In this study, it is aimed to investigate the effects of production methods on the physical properties of 20% Ag2O and different ratios of Y211 added YBCO samples. In this context, the samples with Y123 + x % (x = 20, 25, 30) Y211 + 20%Ag2O compositions were fabricated by MPMG and TSMG methods in two groups to join YBCO main samples. XRD measurements were performed to determine the characteristic peaks. Trapped magnetic fields and vertical levitation forces between the bulk samples and a permanent magnet were measured using a computer-controlled system in ZFC at 77 K. From the XRD measurements, it was found that MPMG YBCO samples had a dominant superconducting structure and partially showed orientation peaks in the c-axis direction, while TSMG YBCO samples were single-crystal samples oriented along the c-axis. From the trapped magnetic field measurement results, the trapped magnetic field value of the Y123 + 25%Y211 + 20%Ag2O (TAg25) sample prepared by the TSMG method was higher than that of the other samples. Among the levitation force measurement results, the maximum repulsive force values of TAg25 and TAg30 (Y123 + 30%Y211 + 20%Ag2O) samples are the highest. At the same time, the hysteresis widths of these samples are also the highest, which proves that their flux-pinning potential is higher than that of the other samples.

    AtıfScopus5WoS3OpenAlex5
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  • MakaleYalnız künye2023Scopus SJRQ1
    Detection of forest fire using deep convolutional neural networks with transfer learning approach[Formula presented]

    Reis, Hatice Catal; Turk, Veysel

    Forest fires caused by natural causes such as climate change, temperature increase, lightning strikes, volcanic activity or human effects are among the world's most dangerous, deadly, and destructive disasters. Detection, prevention, and extinguishing forest fires is challenging. In addition, forest fires can cause habitat destruction that cannot be controlled in time and cause great material and moral losses. Therefore, fast and accurate Detection of forest fires is vital in emergency response. Here, in solving the problem, the transfer learning method from deep learning sub-topics can be used, which allows the application of pre-trained networks to a new problem. The Fire Luminosity Airborne-based Machine learning Evaluation dataset (consisting of forest fire images) obtained by Unmanned Aerial Vehicle was used in this study. In the Detection of forest fire images in the dataset, InceptionV3, DenseNet121, ResNet50V2, NASNetMobile, VGG-19 deep learning algorithms, transfer learning techniques that can produce more successful results than networks trained from scratch, and hybrid proposed with Support Vector Machine, Random Forest, Bidirectional Long Short-Term Memory, Gated Recurrent Unit algorithms methods have been applied. In the classification study with the Fire Luminosity Airborne-based Machine learning Evaluation dataset in performance measurement, 97.95% accuracy was obtained from the DenseNet121 model, which was started with random weights. In the transfer learning study using ImageNet weights, satisfactory results were obtained with 99.32% accuracy in the DenseNet121 model. We anticipate that working in forest fire detection and response can be entirely satisfactory.

    • SDG 15 · Karasal Yaşam
    AtıfScopus87WoS64OpenAlex92
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  • MakaleYayıncıda açık erişim2023Scopus SJRQ1
    MediNet: transfer learning approach with MediNet medical visual database

    Reis, Hatice Catal; Turk, Veysel; Khoshelham, Kourosh; Kaya, Serhat

    The rapid development of machine learning has increased interest in the use of deep learning methods in medical research. Deep learning in the medical field is used in disease detection and classification problems in the clinical decision-making process. Large amounts of labeled datasets are often required to train deep neural networks; however, in the medical field, the lack of a sufficient number of images in datasets and the difficulties encountered during data collection are among the main problems. In this study, we propose MediNet, a new 10-class visual dataset consisting of Rontgen (X-ray), Computed Tomography (CT), Magnetic Resonance Imaging (MRI), Ultrasound, and Histopathological images such as calcaneal normal, calcaneal tumor, colon benign colon adenocarcinoma, brain normal, brain tumor, breast benign, breast malignant, chest normal, chest pneumonia. AlexNet, VGG19-BN, Inception V3, DenseNet 121, ResNet 101, EfficientNet B0, Nested-LSTM + CNN, and proposed RdiNet deep learning algorithms are used in the transfer learning for pre-training and classification application. Transfer learning aims to apply previously learned knowledge in a new task. Seven algorithms were trained with the MediNet dataset, and the models obtained from these algorithms, namely feature vectors, were recorded. Pre-training models were used for classification studies on chest X-ray images, diabetic retinopathy, and Covid-19 datasets with the transfer learning technique. In performance measurement, an accuracy of 94.84% was obtained in the traditional classification study for the InceptionV3 model in the classification study performed on the Chest X-Ray Images dataset, and the accuracy was increased 98.71% after the transfer learning technique was applied. In the Covid-19 dataset, the classification success of the DenseNet121 model before pre-trained was 88%, while the performance after the transfer application with MediNet was 92%. In the Diabetic retinopathy dataset, the classification success of the Nested-LSTM + CNN model before pre-trained was 79.35%, while the classification success was 81.52% after the transfer application with MediNet. The comparison of results obtained from experimental studies observed that the proposed method produced more successful results. Graphical abstract: [Figure not available: see fulltext.]

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus16WoS14OpenAlex18
    ScopusWeb of SciencePubMedİncele
  • Kitap BölümüYalnız künye2023
    Long distance relationship with workplace: Remote work and workplace spirituality

    Demirbağ, Kübra Şimşek

    In this study, workplace spirituality is discussed in the context of remote work and the COVID-19 pandemic. First, the focus is on the changes in the meaning and function of employees in the organization during the evolutionary process of industrialization and management paradigms. Afterward, conceptual frameworks for spirituality and workplace spirituality are presented, and in the last section, academic studies that deal with workplace spirituality with distance or hybrid work arrangements are included. Early studies offer insights and recommendations on conceptualizing, developing, and managing workplace spirituality. They all emphasize that spirituality is necessary for remote work as a tool to overcome stress and mental health problems and increase employee well-being. Unfortunately, the remote work and workplace spirituality literature is relatively narrow and needs to be expanded.

    • SDG 8 · İnsana Yakışır İş ve Ekonomik Büyüme
    AtıfScopus2OpenAlex4
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