Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Dertli, Enes(114)
- Kaya, Yunus(48)
- Şahin, Engin(48)
- İspirli, Hümeyra(47)
- Özen, Soner(38)
- Şenay, Volkan(37)
- Pat, Suat(36)
- Kutlu, Naciye(32)
- Artar, Musa(31)
- Can, Zehra(31)
- Korkmaz, Şadan(31)
- Yilmaz, Mustafa Tahsin(31)
- Öner, Erdal(31)
- Bayram, Sinan(30)
- Cuce, Erdem(30)
- Ertugrul, Mehmet(29)
- Hasar, Ugur Cem(29)
- Ecem Bayram, Nesrin(28)
- Mercan, Emin(28)
- Ayata, Ümit(27)
- Bayraktar, Bülent(27)
- Çolak, Murat(23)
- Özdemir, Akın(23)
- Ayazoglu, Rabil(22)
- Cuce, Pinar Mert(22)
- Sert, Durmuş(22)
- Bayram, Ozkan(21)
- Kamiloğlu, Aybike(21)
- Dirican, Ebubekir(20)
- Kadakal, Mahir(20)
- Abdioglu, Murat(19)
- Birinci, Ahmet(19)
- Tozlu, Alperen(19)
- Gerçek, Yusuf Can(18)
- Taylan, Osman(18)
- Cinar, Mehmet(17)
- Gul, Volkan(16)
- Hasar, Ugur C.(16)
- Kadakal, Huriye(16)
- Kara, Yakup(16)
Yayınlar
- MakaleAçık Erişim2023Scopus SJRQ2Suberosin Alleviates Sepsis-Induced Lung Injury in A Rat Model of Cecal Ligation and Puncture
Karabulut Uzunçakmak, Sevgi; Halıcı, Zekai; Karakaya, Songül; Kutlu, Zerrin; Sağlam, Yavuz Selim; Bolat, İsmail; Aydın, Pelin; Kılıç, Ceyda Sibel
Background/aims: Sepsis is one of the major problems encountered in intensive care units, causing organ damage and increasing mortality. Suberosin (SBR) is a type of coumarin with antioxidant and anti-inflammatory activities. The goal of this study is to explore the protective effects of SBR on the lungs in a rat model of sepsis. Methods: Male Wistar rats were utilized in this study. A cecal ligation and puncture (CLP) model was applied to induce sepsis. Rats were separated into six groups with nine animals in each group, including healthy control, SBR, CLP, and CLP + SBR (5, 10, and 20 mg/kg) groups. Superoxide dismutase (SOD), glutathione (GSH) enzyme activities, and malondialdehyde (MDA) level were measured via enzyme-linked immunosorbent assay (ELISA). The messenger RNA (mRNA) expressions of tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β) were evaluated by real-time polymerase chain reaction (RT-PCR). Histopathological changes in the lungs were investigated with hematoxylin and eosin (H&E). Results: MDA levels and GSH and SOD enzyme activities were negatively affected in the CLP group, but SBR treatment ameliorated these oxidative stress parameters in the SBR1-3 groups (p< 0.05). The mRNA expressions of TNF-α and IL-1β were increased in the CLP group, and SBR treatment decreased those expression levels in a dose-dependent manner (p < 0.05). Organ damage and necrosis were seen in the CLP group and were alleviated in the SBR3 group. Immunohistochemical (IHC) analysis of lung tissues demonstrated decreased TNF-α and IL-1β immunopositivity in the SBR1-3 groups (p< 0.05). Conclusions: SBR ameliorated sepsis-related lung injury in a dose-dependent manner. This compound has significant potential as a future agent in the treatment of sepsis.
AtıfScopus15WoS11OpenAlex15
İncele - MakaleAçık Erişim2023Scopus SJRQ3A Study on YouTube Channels of Foreign Languages Teaching Foundation
Maden, Sedat; Kaya, Musa
This study was conducted to examine the YouTube channels of Yunus Emre Institute, British Council, Institut Français, Instituto Cervantes, Confucius Institute and Goethe Institut foundations having channels on YouTube, one of the largest video sharing platforms of the world. The channels in this study, were examined through the qualitative research method in terms of the upload date, the numbers of subscribers, the numbers of videos, the videos’ grouping status, the number of video views, and the features of the most watched videos. As a result of the study, it appears that Yunus Emre Institute created its YouTube channel in 2014, British Council in 2010, Institut Français in 2017, Instituto Cervantes in 2017, Confucius Institute (U.S.) in 2017 and Goethe Institute in 2007. Yunus Emre Institute, one of the channels on YouTube, has more than 64400 subscribers, British Council has 542000, Institut Français has 3650, Instituto Cervantes has 69100, Confucius Institute has 801, and Goethe Institute has 301000. It is found that Yunus Emre Institute has 925, British Council has 134, Institut Français has 463, Instituto Cervantes has 1115, Confucius Institute has 82, and Goethe Institute has 1152 videos on YouTube. It has been determined that YouTube channels belonging to institutions established to teach the world's most spoken languages were created adopting similar paradigms and after the year 2007.
AtıfScopus1OpenAlex1İncele - MakaleAçık Erişim2023Scopus SJRQ1Sustainability Ranking of Turkish Universities with Different Weighting Approaches and the TOPSIS Method
Akyol Özcan, Kübra
The concept of sustainability has become more important, especially as a result of the depletion of energy resources and increasing environmental concerns. UI GreenMetric ranks universities based on sustainability, environmental, and energy concerns, addressing issues of environmental pollution, food and water scarcity, and energy supply. By prioritizing sustainability on their campuses and campuses, universities are working to ensure a more sustainable future for humanity. This study evaluates university sustainability in energy and climate change using the UI GreenMetric ranking, focusing on Turkish universities’ sustainability ranking. It incorporates variables like infrastructure, energy, climate change, waste, water, public transportation, and educational research, using weighting approaches to reveal the most important variables for the country’s universities. The study utilized weighting techniques like CRITIC, entropy, standard deviation-based, and equal weighting approaches to obtain rankings for UI GreenMetric rankings. Entropy and equal weighting methods were found to be closest to the UI GreenMetric rankings. Universities’ rankings were analyzed using the TOPSIS method and four weighting techniques for 83 Turkish universities. For Turkish universities, the CRITIC method yielded the highest weight for energy and climate change variables, while water was identified as the most significant factor for entropy, installation infrastructure, and standard deviation-based weighting techniques.
AtıfScopus13WoS11OpenAlex15İncele - MakaleAçık Erişim2023Scopus SJRQ3Preventive and therapeutic effects of the peel powder of P. granatum in a rat sepsis model; [Preventivni i terapijski učinci praha kore pitomog šipka (P. Granatum) na modelu sepse u štakora]
Ülker, Ufuk; Demirel, Mürşide Ayşe; Bayraktar, Bülent; Alçıgır, Mehmet Eray; Aksoy, Adil
The aim of the present study was to evaluate the treatment potential of Punica granatum L. peel powder in an experimentally induced sepsis model in rats. Sepsis was induced in 10-week-old, male, Wistar Albino (n=24) rats. The animals were divided into four groups: Sham-operated (S) Group, Control (C) Group, Treatment-1 (T1) Group, and Treatment-2 (T2) Group. To induce the sepsis model, the cecal ligation and puncture procedure was performed. The P. granatum peel powder (200 mg/kg; per os) was applied one hour before (T1) and 10 hours after (T2) surgery in a volume of 2 mL. At the end of the experimental procedure, microbial and histopathological analyses were performed. The histopathological scores on the liver, lungs, heart, kidney, spleen, and pancreas were evaluated. Escherichia coli, Staphylococcus aureus and E. coli + S. aureus were isolated from blood cultures. Severe bacteria were detected in the blood of the group C animals. It was found that there were fewer bacteria in groups T1 (n=2) and T2 (n=4) compared with group C. There were no lesions in the pancreas tissues of any groups. Vascular changes, degeneration, and necrosis were common in the organs in all cases of group C compared to group S. The findings in group T1 were similar to those in group C, however, it was seen in fewer animals. It was determined that there was a general improvement in group T2, and in addition the existing lesions were moderate in severity. In conclusion, P. granatum L. peel powder prevented CLP-induced lung injury in experimental rats. Thus, P. granatum L. peel powder may be an alternative therapeutic agent against lung tissue injury induced by sepsis. The recovery from inflammation was better in group T2 than in the other groups. According to the results of the current study, P. granatum peel powder was found to be effective in the treatment of sepsis with antimicrobial and anti-inflammatory functions.
AtıfScopus1WoS1OpenAlex1İncele - MakaleAçık Erişim2023Scopus SJRQ3Synthesis of Arylsulfonyl Hydrazone Derivatives: Antioxidant Activity, Acetylcholinesterase Inhibition Properties, and Molecular Docking Study
Demirci, Yasin; Kalay, Erbay; Kara, Yakup; Güler, Halil İbrahim; Can, Zehra; Şahin, Engin
In this current paper, fifteen novel sulfonyl hydrazone derivatives have been successfully synthesized and evaluated for antioxidant activity as well as their effects on inhibitory activity toward acetylcholinesterase (AChE). By using 1H NMR, 13C NMR, FT-IR, and high-resolution mass spectrometry methods, the full characterization data of the novel compounds were obtained. The synthesized compounds capacity to inhibition glucosidase and exhibit antioxidant activity were tested in vitro. It was determined that compounds (E)-4-((2-((4-chlorophenyl)sulfonyl)hydrazone)methyl)-2-methoxyphenylfuran-2-carboxylate (21), (E)-2-methoxy-4-((2-(phenylsulfonyl)hydrazone)methyl)phenylfuran-2-carboxylate (17) and (E)-4-((2-((4-bromophenyl)sulfonyl)hydrazone)methyl)-2-methoxyphenylfuran-2-carboxylate (25) showed good antioxidant activity. Upon examining the acetylcholinesterase inhibitory activity, it was determined that compounds (E)-2-methoxy-4-((2-((4-methoxyphenyl)sulfonyl) hydrazone)methyl)phenylacetate (27) (10.39 μM), (E)-4-((2-((4-chloro phenyl)sulfonyl) hydrazone)methyl)-2-methoxyphenylfuran-2-carboxylate (21) (10.81 μM), (E)-4-((2-((4-chloro phenyl)sulfonyl)hydrazone)methyl)-2-methoxyphenyl thiophene-2-carboxylate (22) (12.92 μM) and (E)-2-methoxy-4-((2-(phenylsulfonyl)hydrazone)methyl)phenylfuran-2-carboxylate (17) (12.93 μM) showed potent inhibitory effects. Molecular docking simulations were used to investigate the interactions of novel sulfonyl hydrazone derivatives with human acetylcholinesterase protein. The ligands exhibited strong binding to the receptor protein with potent inhibition.
AtıfScopus18WoS18OpenAlex19İncele - MakaleYalnız künye2023Scopus SJRQ3Methoxy-activated indole-7-carbohydrazides; synthesis, antioxidant, and anticancer properties
Kandemir, Hakan; İzgi, Samet; Cınar, Irfan; Cebeci, Fatma; Dirican, Ebubekir; Saglam, Mehmet F.; Sengul, Ibrahim F.
Indole has been known as a key heterocyclic motif in the development of new structures for both chemical and biological properties. In this current study, a new range of indole-7-carbohydrazides has been successfully synthesized starting from the readily available 3-phenyl and 2,3-diphenyl 4,6-dimethoxyindoles. The structures of the novel compounds were confirmed by utilizing 1H NMR, 13C NMR, FT-IR, high-resolution mass spectrometry, and single crystal X- ray diffraction techniques. In addition, the indole-7-carbohydrazides showed promising antioxidant results in preliminary screens. Some of the new compounds generated from dimethoxy indoles were also screened for their anticancer activity against SH-SHY5Y (human neuroblastoma), AGS (human gastric adenocarcinoma), and MDA-MB-231 (human breast adenocarcinoma) cell lines. The results revealed that the compound 12 was the promising candidate, showing cytotoxic effects on both neuroblastoma, stomach, and breast cancer cells.
AtıfScopus4WoS4OpenAlex6İncele - MakaleAçık Erişim2023Scopus SJRQ1Evaluation of Optimal Energy Productıon Usıng Deterministic, Probabilistic and Risky Cases In a Multi-Reservoir System
Bacaksız, Efsun; Opan, Mücahit; Kara Dilek, Zuhal Elif; Karadeniz, Murat
In a multi-reservoir system, the stochastic nature of basin data resulting from rainfall introduces risk into water management operations. Effective management that accounts for these risks can obtain maximum benefits from the system. This study presents a description of a multi-reservoir water resources system with hydroelectric power plants, utilizing the energy optimization model developed by OPAN in 2007. The model was applied to reservoirs located successively on the Lower Kızılırmak River in the Kızılırmak Basin, with the objective function being the maximization of firm power by using drought period inflows and total energy by using monthly average inflows. The study considered three scenarios: deterministic, probabilistic, and risky (critical cases), with probabilities of inflows from the basin being determined for the latter. Monthly inflows with determined probabilities were used to obtain data for the risky case. Optimum operating levels were determined based on this data to maximize firm power and total energy. According to the operating levels, the reservoir with the largest useful volume manages the operation. The values obtained from the optimization were then used in multivariate regression analysis using the Statistical Package for Social Scientists (SPSS), a statistical analysis program. The analysis explored the effects of monthly operating levels in the reservoirs, the amount of inflow released from the spillway, the amount of inflow released for energy production, the monthly average inflow to the reservoirs, and firm power values on energy production.
AtıfScopus7WoS6OpenAlex7İncele - MakaleAçık Erişim2023Scopus SJRQ3Bounds for the blow-up time a class of integro-differential problem of parabolic type with variable reaction term; [Bornes sur le temps d’explosion pour une équation intégro-différentielle de type parabolique avec un terme réactif variable]
Ayazoglu, Rabil; Akkoyunlu, Ebubekir
This paper is concerned with the blow-up time of the solutions to an integro-differential problem of parabolic type with variable growth if blow-up occurs. By using the differential inequality technique, we obtain lower bounds for the blow-up time and some global existence results under some conditions to variable exponent of reaction, memory kernel, and initial value.
AtıfScopus1WoS1İncele - MakaleAçık Erişim2023Scopus SJRQ3An Investigation of Digital Transformation Activities of Higher Education in Türkiye
Yavuz, Mehmet; Kayalı, Bünyami; Karaman, Selçuk
This study aimed to examine the digital transformation activities of universities. The document analysis method was used in the study, one of the qualitative research methods. In this context, the websites of 207 universities were examined using the "Digital transformation activities form of universities" developed by the researchers. The data were analyzed by content analysis method. As a result of the analysis, six broad themes, also called dimensions in the current study, emerged, such as research, education, culture, process, technology, and community service regarding digital transformation activities of higher education institutions. Infrastructure studies, educational activities for research and supply and the use of smart systems to provide various cooperation opportunities are discussed within the scope of the research dimension. There are online scientific studies, online education programs, digital resources, and open access opportunities in the education dimension. As for the culture dimension, online manager activities for corporate culture, training of trainers, culture-arts and scientific activities took place. With the transfer of business processes to the digital environment, corporate promotion and communication activities were included in the process dimension. In the technology dimension, smart systems, smart campus applications and innovative technologies took place. Finally, the scope of community service compromised related units, university-industry cooperation activities and social activities. As a result, universities carry out activities to support processes such as education, research, management, and cooperation and to realize them in digital environments. For this purpose, it can be said that they perform effective and efficient processes by using various intelligent systems.
AtıfScopus7OpenAlex10İncele - MakaleYalnız künye2023Scopus SJRQ1Honey-Water Content Analysis by Mixing Models Using a Self-Calibrating Microwave Method
Hasar, Hafize; Hasar, Ugur C.; Kaya, Yunus; Ozturk, Hamdullah; Izginli, Mucahit; Oztas, Taskin; Aslan, Nevzat; Ertugrul, Mehmet; Barroso, Joaquim J.; Ramahi, Omar M.
Microwave techniques, as an indirect approach, can be applied for analyzing water content in honey by way of permittivity measurements. However, these techniques require proper calibration to accurately perform such indirect evaluation. Improper calibration standards used in this calibration process could naturally result in a reduction in the accuracy and thus the performance of dielectric characterization using microwaves. Self-calibrating microwave techniques can reduce the effects of imprecise standards and thus improve the performance of microwave measurements by bypassing the requirement of calibration standards. In this study, we develop a self-calibrating microwave measurement technique to determine the relative permittivity of honey samples and implement binary mixing models to predict adulteration levels of water-adulterated honey. From this implementation, it is observed that the parallel-capacitance mixing model could efficiently be applied to determine the concentration of water adulteration by examining the differences between absolute values of the real parts of the measured and predicted complex permittivities of adulterated honey.
AtıfScopus18WoS16OpenAlex18İncele - MakaleAçık Erişim2023Scopus SJRQ3EVALUATION OF YIELD AND QUALITY CHARACTERISTICS OF OIL SUNFLOWER (Helianthus annuus L.) VARIETIES CULTIVATED IN SEMI-ARID IRRIGATED CONDITIONS IN THE NORTHEAST OF TURKEY
Gul, Volkan; Gidik, Betul; Sefaoglu, Firat
Sunflower, an oil plant grown in many parts of the world, is capable of growing in many different climatic conditions. It is of great importance to carry out studies on the adaptation of new varieties and to determine the varieties suitable to the ecology of the region in areas where sunflower cultivation is intense. This study was carried out to determine yield and quality characteristics of some sunflower cultivars (SANBROMR, BOSFORA, SYBARBATI, ROSETTA, LG5485, P64LL62, SYGIBRALTAR, P64LC108 P64LE119, P64LP130, P63LE113, 11TR077, ESNIEGARA, ADELYA, and DERAY) under Bayburt providence conditions of Turkey in 2020-2021. It has been determined that there are significant differences between the cultivars for the traits examined. The highest average seed yield (4194.2 kg ha-1) and average linoleic acid content (65.09%) were found for BOSFORA. The highest average oil content ESNIEGARA (48.78%) and average oil yield respectively were obtained from ESNIEGARA (186.02 kg ha-1) and BOSFORA (182.93 kg ha-1) varieties and the highest average oleic acid content was obtained from 11TR077 variety (41.78%). The results of this study emphasized the importance of varieties in sunflower growing. BOSFORA and ESNIEGARA varieties had high yield and quality characteristics in the ecologies of a semi-arid climate.
AtıfScopus1WoS1OpenAlex1İncele - MakaleAçık Erişim2023Scopus SJRQ2Extraction of Functional Compounds from Tarragon (Artemisia dracunculus L.) by Deep Eutectic Solvents at Different Properties
Can Gerçek, Yusuf; Kutlu, Naciye; Çelik, Saffet; Gıdık, Betül; Bayram, Sinan; Bayram, Nesrin Ecem
In this study, it was aimed to examine the capacity of deep eutectic solvents (DESs) with different contents to extract bioactive compounds from tarragon (Artemisia dracunculus L.) plant. For this reason, the total phenolic-flavonoid content, total proanthocyanidin content and antioxidant/antimicrobial activities of the prepared DES extracts were investigated, as well as the individual phenolic and individual amino acid profiles. According to the results, DES10 had the highest efficiency in terms of its capacity to extract individual phenolics (approximately 59 mg/100 g) and individual amino acids (approximately 2500 mg/kg), and also gave a higher yield compared to ethanol (approximately 44 mg/100 g for individual phenolics and about 19810 mg/kg for individual amino acids) and methanol (approximately 58 mg/100 g for individual phenolics and approximately 21430 mg/kg for individual amino acids). However, the total phenolic content, total flavonoid content and antioxidant activity values of DES extracts were determined between 59.09–77.50 mg GAE/100 g, 28.68–45.55 mg GAE/100 g and 42.96–146.86 mg TE/100 g, respectively. Therefore, it can be recommended to use these green solvents, which are known as environmentally friendly, as an alternative to organic solvents in the process of preparing extracts of this important medicinal plant in different areas.
AtıfScopus8WoS6OpenAlex9İncele - MakaleAçık Erişim2023Scopus SJRQ2Investigation of organic and inorganic matters removal from tannery wastewater using iron plate electrode by electrocoagulation process
Bingül, Züleyha; Irdemez, Şahset; Kul, Sinan; Ekmekyapar Torun, Fatma; Demircioğlu, Nuhi
In this study, COD, turbidity, total nitrogen, phosphate, sulphate, oil-grease and chromium removals from wastewaters taken from a local tannery using the electrocoagulation process were examined and the most suitable parameters for the electrocoagulation system were tried to be determined. Soluble iron plate electrodes were used as electrodes in the experiments. As a result of the studies carried out, the most suitable initial pH in uncontrolled pH was determined as pH = 4 and for controlled pH as pH = 5. In studies, the most suitable current density for iron electrodes was determined as 1.2 mA cm−2. Even if the increase in current density increased the amount of dissolved Fe, it negatively affected the removal efficiency. In addition, the turbidity of the wastewater was removed in 30 minutes, phosphate in 20 minutes and chromium in 15 minutes by 100%. During 60 minutes of operation, while 62.91% of TN, 87.8% of oil-grease were removed, sulphate was removed at the rate of 54.78%. In the studies, 1st and 2nd order kinetic equations for COD removal were examined and it was determined that removal kinetic is more suitable for 2nd order kinetics.
AtıfScopus7WoS4İncele - MakaleAçık Erişim2023Scopus SJRQ2Experimental study of adhesively bonded joints with dissimilar composite laminates under different loading rates and ambient temperatures
Erbayrak, Engin; Gumus, Beril Eker; Yuncuoglu, Ercument Ugur
An experimental study of the single-lap joints at different loading rates and ambient temperatures was investigated. In the experiment, a single lap joint was formed using plain woven glass fiber reinforced epoxy (GFRE) laminates, plain woven aramid fiber reinforced laminates (AFRE), and Araldite 138 M / HV998 epoxy adhesive. The composite laminates were produced using Vacuum-Assisted Resin Transfer Molding (VARTM) process. Adhesively bonded joints were created using similar and dissimilar adherends. Experiments were carried out under different loading rates (1 mm/min, 10 mm/min, 50 mm/min, 100 mm/min) and ambient temperatures (23°C,60°C,100°C). Stress–strain graphs were obtained for each experimental condition. It is seen that the maximum stress values increase as the loading rate increases in all single lap joints at all different temperatures. However, in all single lap joints, at all different loading rates, the maximum stress value decreases as the ambient temperature increases.
AtıfScopus7WoS7OpenAlex7İncele - MakaleAçık Erişim2023Scopus SJRQ3The effect of heart failure on gut microbial richness and diversity; [O efeito da insuficiência cardíaca estável na riqueza e diversidade microbiana intestinal]
Kilic, Oguz; Kaya, Halil Ibrahim; Secme, Mucahit; Kilinc, Mehmet; Sevgican, Cihan Ilyas; Buber, Ipek; Dodurga, Yavuz; Simsek, Omer; Ergin, Cagrı; Kilic, Ismail Dogu
Introduction and objective: With recent advances in genome sequencing technology, a large body of evidence has accumulated over the last few years linking alterations in microbiota with cardiovascular disease. In this study, we aimed to compare gut microbial composition using 16S ribosomal DNA (rDNA) sequencing techniques in patients with coronary artery disease (CAD) and stable heart failure (HF) with reduced ejection fraction and patients with CAD but with normal ejection fraction. We also studied the relationship between systemic inflammatory markers and microbial richness and diversity. Methods: A total of 40 patients (19 with HF and CAD, 21 with CAD but without HF) were included in the study. HF was defined as left ventricular ejection fraction <40%. Only stable ambulatory patients were included in the study. Gut microbiota were assessed from the participants’ fecal samples. The diversity and richness of microbial populations in each sample were assessed by the Chao1-estimated OTU number and the Shannon index. Results: The Chao1-estimated OTU number and Shannon index were similar between HF and control groups. There was no statistically significant relationship between inflammatory marker levels (tumor necrosis factor-alpha, interleukin 1-beta, endotoxin, C-reactive protein, galectin-3, interleukin 6, and lipopolysaccharide-binding protein) and microbial richness and diversity when analyzed at the phylum level. Conclusion: In the current study, compared to patients with CAD but without HF, stable HF patients with CAD did not show changes in gut microbial richness and diversity. At the genus level Enterococcus sp. was more commonly identified in HF patients, in addition to certain changes in species levels, including increased Lactobacillus letivazi.
AtıfScopus8OpenAlex7İncele - MakaleYalnız künye2023Scopus SJRQ1Full-scale structural evaluations of İskenderpaşa minaret
Aymelek, Abdullah; Yanik, Yusuf; Demirtaş, Betül; Yildirim, Ömer; Çalik, İsmet; Türker, Temel
Nowadays, innovative methods have been used for observing and structural evaluating of historical structures. In this paper, it is presented the full-scale structural assessments of a minaret after a Finite Element model calibrating according to vibration test results. Also, the structural behaviours under earthquake and wind loads were identified by considering the environmental effects on the selected masonry minaret of İskenderpaşa Mosque. First of all, modal analysis was executed on the three-dimensional Finite Element model created according to field survey in ANSYS Workbench. In-situ vibration tests were implemented at different intervals by using developed vibration measurement system. The experimental modal parameters were attained from collected signals. The experimental results were used as reference values in model calibration of this minaret to reflect the existing structural behaviour. Model calibration process was carried out on the initial model both by changing of material properties of masonry wall and by taking into account the interactions with mosque walls and ground. Full-scale structural evaluation was carried out under earthquake and wind loads on both the initial and the calibrated models in the weak direction of this minaret. The top displacements, drift ratios, principal stress values and their distributions were determined. It was shown that the analyses on the calibrated model produce more realistic structural behaviour.
AtıfScopus21WoS20OpenAlex22İncele - MakaleAçık Erişim2023Scopus SJRQ3A study on Li-ion battery and supercapacitor design for hybrid energy storage systems
Çorapsiz, Muhammed Reşit; Kahveci, Hakan
This paper discusses a generic design of lithium-ion (Li-ion) batteries and supercapacitors, which are important sources for energy storage systems (ESS). The main contribution of this study is to compare the available and experimental models for batteries and supercapacitors operating under continuous charge or discharge conditions. Even though the available models show similar behavior to the experimental ones in short-term or pulsed discharge conditions, this situation may be different in continuous discharge conditions. For this purpose, the optimal electrical equivalent circuits of energy storage devices were constituted and modeled in the MATLAB/Simulink environment. Then, the electrical equivalent circuit parameters were approximately calculated with the help of dynamic equations. Finally, the model parameters were estimated using Nonlinear Least Squares Method (NLSM) and Trust Region Reflective Algorithm (TRRA). When the obtained results were evaluated together, it has been observed that the electrical equivalent circuit models (EECM) more accurately reveal the transient and steady states of energy storage devices compared to the available models, especially under continuous discharge conditions.
AtıfScopus33WoS30OpenAlex33İncele - MakaleYalnız künye2023Scopus SJRQ1Genetic algorithm enabled virtual multicast tree embedding in Software-Defined Networks
Guler, Evrim; Karakus, Murat; Ayaz, Furkan
The recent network virtualization technology enables the multi-tenancy, where various virtual network requests can share the same physical network by decoupling network services from the underlying hardware architecture. The process of virtual node and link mapping onto a shared Substrate Network (SN) by satisfying the requested network resources (i.e., bandwidth, computing capacity, etc.) is referred to as Virtual Network Embedding (VNE), which is known as an NP-Hard problem. The problem of VNE aims to exhibit one-to-one (unicast) communication. However, the motivation of this research is to explore how to efficiently map virtual networks with one-to-many (multicast) communications, which are in the form of Virtual Multicast Trees (VMTs), onto an SN. This problem differs from the traditional VNE problem and has not been well-studied by the research community. To this end, we propose a novel algorithm, Modified Genetic Algorithm for Virtual Multicast Tree Embedding (MGA-VMTE), to embed VMTs onto a shared SN in this research. The proposed MGA-VMTE algorithm focuses on minimizing the network resource consumption (i.e., bandwidth) under end-to-end delay constraint in the SN while satisfying the computing request of virtual nodes. Our extensive simulations demonstrate that the MGA-VMTE algorithm outperforms the dynamic impact factor and traditional greedy-based virtual multicast tree embedding approaches regarding bandwidth consumption, acceptance ratio, and resource depletion ratio metrics on NSFNET, USNET, Random-60 node, and Random-120 node network topologies.
AtıfScopus16WoS12OpenAlex16İncele - MakaleAçık Erişim2023Scopus SJRQ2The effect of guided imagery on postoperative pain and comfort of geriatric orthopaedic patients: a randomized controlled trial
Ozdemir, Ahmet; Gunes, Hüseyin; Saritas, Serdar
Background: The purpose of this study is to investigate the effects of guided imagery on postoperative pain and comfort in geriatric orthopedics patients. Methods: This study was carried out with a randomized-controlled true experimental design. The population of the study included geriatric patients receiving treatment at the orthopedics and traumatology inpatient clinic of a university hospital. Based on random selection, the sample consisted of total of 102 patients, including 40 patients in the experimental group and 40 in the control group. The data were collected using a Personal Information Form, the Visual Analog Scale, and the General Comfort Questionnaire. Results: After the guided imagery intervention, the pain levels of the experimental group significantly decreased compared to their baseline pain levels (t = 4.002, P = 0.00). Their perceived comfort was also significantly improved (t = −5.428, P = 0.00). Although the perceived comfort of the control group decreased, this decrease was not statistically significant (t = 0.698, P = 0.489). Conclusion: It is recommended that guided imagery, which is an inexpensive and accessible method, be integrated into the nursing care process to reduce the pain and increase the comfort of geriatric orthopedics patients.
AtıfScopus3WoS1OpenAlex4İncele - MakaleYalnız künye2023Scopus SJRQ1Electrical, Magnetic, Microstructural, and Characteristic Properties of Zirconium-Substituted Co0.5 Ni0.5 Zrx Fe2− x O4 Spinel Ferrite Nanostructures
Teber, Ahmet; Sarac, Mehmet F.
The effect of zirconium (Zr) substitution in nickel–cobalt ferrites, Co0.5Ni0.5ZrxFe2−xO4 (0.0 ≤ x ≤ 1.0) produced by the hydrothermal method on the electrical, magnetic, microstructural and characteristic properties are reported. A secondary phase as tetragonal-ZrO2 phase in the crystal system is detected and have both M-type hexagonal and tetragonal nanocrystallites between 32 and 67 nm. Refined structural parameters using Rietveld analysis are carried out, resulting in lattice parameters, the unit cell volume, parameter ratios, and the crystallite size using the TOPAS refinement program. In addition, residuals for the RBragg factor and goodness of fit (χ2) value for each concentration are represented. The Rietveld analysis determines that the predicted and actual diffraction patterns are in accord. Furthermore, the Zr effect is presented in unit volume as seen by the drop in peak intensity that occurs (with the addition of Zr) due to the lattice tension. Moreover, the morphological analyses indicate that the shape transformed from agglomerated clusters to oval-shaped structures and a reduction in grain size. Fourier transform infrared (FT-IR) analysis in the range of 4000–450 cm−1 correlates with the presence of the hexagonal spinel ferrite structure. The dielectric parameters, such as the relative permittivity, tangent loss, and ac conductivity, are experimentally measured with the oscillation voltage level of 0.05 V in the frequency range of 0.1–10 MHz. The dielectric permittivities and tangent losses of the specimens decreased with an increment in frequency. Magnetic measurements reveal that the values of coercivity (Hc) have the propensity to increase relating to the zirconium concentration.
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