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 Erişim2024Scopus SJRQ3Green Synthesis of Selenium Nanoparticles using Green Coffee Beans: An Optimization Study
Baluken, Pınar; Kamiloglu, Aybike; Kutlu, Naciye
In this study, ultrasonication extraction of some bioactive compounds from green coffee beans was optimized with the response surface method using Box-Behnken experimental design. The best condition was selected as 90.90 W ultrasonic power, 33.63 min sonication time and 30 % solid concentration. The responses obtained under optimum conditions had TPC, DPPH and CUPRAC values identified as 6603.33±2025.94 ppm GAE, 9638.31±372.17 ppm TE and 98.83 mmol, respectively. Microwave-assisted selenium nanoparticle production was carried out using the extract obtained under optimized conditions. The produced selenium nanoparticles showed absorbance between 350–400 nm. The surface morphology and size of the nanoparticles were determined by transmission electron microscopy (TEM) and spherical nanoparticles of about 100 nm were produced. Functional groups affecting the reduction were determined by FTIR analysis. In addition, the produced selenium nanoparticles had amorphous (non-uniform) structure and could maintain their stability at high temperatures.
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İncele - MakaleYayıncıda açık erişim2024Scopus SJRQ1The effect of bed exercises following major abdominal surgery on early ambulation, mobilization, pain and anxiety: A randomized-controlled trial
Simsek Yaban, Zuleyha; Bulbuloglu, Semra; Kapikiran, Gurkan; Gunes, Huseyin; Kula Sahin, Sennur; Saritas, Serdar
This randomized-controlled trial aimed to investigate the effect of bed exercises on postoperative anxiety, pain, early ambulation and mobilization. This study was conducted with a randomized-controlled trial design and in the general surgical clinic of a research and training hospital. A total of 120 patients (60 in the experimental group and 60 in the control group) scheduled for major abdominal surgery took part in the study. The data were collected using a patient information form, the Anxiety Specific to Surgery Questionnaire and the Visual Analog Scale through face-to-face interviews. The patients in the experimental group performed 15-min bed exercises on the day of their operation, as well as on the postoperative first and second days, and the control group underwent only the routinely performed procedures in the clinic. The data were analysed using descriptive statistics, analysis of variance and t-tests. The sample of our study included major abdominal surgery patients. Ambulation was achieved at a mean time of 4 h earlier in the experimental group. On the postoperative first and second days, the patients in the experimental group had mean mobilization durations that were approximately 2 h longer compared with the patients in the control group. Moreover, the postoperative pain and anxiety levels of the patients in the experimental group were significantly lower than those of the patients in the control group (p < 0.05). We recommend that bed exercises be performed to lower anxiety and pain severity, achieve early ambulation and increase the duration of mobilization among patients following major abdominal surgery.
AtıfScopus7WoS8OpenAlex9İncele - MakaleAçık Erişim2024Scopus SJRQ1The Roles of Personality Traits, AI Anxiety, and Demographic Factors in Attitudes toward Artificial Intelligence
Kaya, Feridun; Aydin, Fatih; Schepman, Astrid; Rodway, Paul; Yetişensoy, Okan; Demir Kaya, Meva
The present study adapted the General Attitudes toward Artificial Intelligence Scale (GAAIS) to Turkish and investigated the impact of personality traits, artificial intelligence anxiety, and demographics on attitudes toward artificial intelligence. The sample consisted of 259 female (74%) and 91 male (26%) individuals aged between 18 and 51 (Mean = 24.23). Measures taken were demographics, the Ten-Item Personality Inventory, the Artificial Intelligence Anxiety Scale, and the General Attitudes toward Artificial Intelligence Scale. The Turkish GAAIS had good validity and reliability. Hierarchical Multiple Linear Regression Analyses showed that positive attitudes toward artificial intelligence were significantly predicted by the level of computer use (β = 0.139, p = 0.013), level of knowledge about artificial intelligence (β = 0.119, p = 0.029), and AI learning anxiety (β = −0.172, p = 0.004). Negative attitudes toward artificial intelligence were significantly predicted by agreeableness (β = 0.120, p = 0.019), AI configuration anxiety (β = −0.379, p < 0.001), and AI learning anxiety (β = −0.211, p < 0.001). Personality traits, AI anxiety, and demographics play important roles in attitudes toward AI. Results are discussed in light of the previous research and theoretical explanations.
AtıfScopus548WoS500OpenAlex688İncele - MakaleYalnız künye2024Scopus SJRQ3Capacity-spectrum push-over analysis of rock-lining interaction model for seismic evaluation of tunnels
Majidian, Sina; Tapkın, Serkan; Tercan, Emre
Evaluation of tunnel performance in seismic-prone areas demands efficient means of estimating performance at different hazard levels. The present study introduces an innovative push-over analysis approach which employs the standard earthquake spectrum to simulate the performance of a tunnel. The numerical simulation has taken into account the lining and surrounding rock to calculate the rock-tunnel interaction subjected to a static push-over displacement regime. Elastic perfectly plastic models for the lining and hardening strain rock medium were used to portray the development of plastic hinges, nonlinear deformation, and performance of the tunnel structure. Separately using a computational algorithm, the non-linear response spectrum was approximated from the average shear strain of the rock model. A NATM tunnel in Turkey was chosen for parametric study. A seismic performance curve and two performance thresholds are introduced that are based on the proposed nonlinear seismic static loading approach and the formation of plastic hinges. The tunnel model was also subjected to a harmonic excitation with a smooth response spectrum and different amplitudes in the fully-dynamic phase to assess the accuracy of the approach. The parametric study investigated the effects of the lining stiffness and capacity and soil stiffness on the seismic performance of the tunnel.
AtıfScopus1WoS1OpenAlex1İncele - MakaleAçık Erişim2024Scopus SJRQ3Construction of a new generalization for n-polynomial convexity with their certain inequalities
Kadakal, Mahir; İşcan, İmdat; Kadakal, Huriye
In this paper, we first construct a new generalization of n-polynomial convex function. That is, this study is a generalization of the definition of "n-polynomial convexity" pre-viously found in the literature. By making use of this construction, we derive certain inequalities for this new generalization and show that the first derivative in absolute value corresponds to a new class of n-polynomial convexity. Also, we see that the obtained results in the paper while comparing with Hölder, Hölder-İşcan and power-mean, improved-power-mean integral inequalities show that the results give a better approach than the others. Finally, we conclude our paper with applications containing some means.
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İncele - MakaleAçık Erişim2024Scopus SJRQ3Investigation of Hot Press and Cold Press Effects on Structural, Electrical and Magnetic Properties of Pyrene Added Bulk MgB2
Erdem, O.
In this paper, the effects of hot pressing and cold pressing on the superconducting properties of pyrene (C16H10) added bulk MgB2 were compared. For this aim, the polycrystalline disk-shaped MgB2 samples with addition of 4 wt % C16H10 powder were fabricated by a pellet/closed tube method at 850 °C, after hot pressing at 200 °C and cold pressing. The XRD and SEM results showed that although a-lattice parameters reduce for both C16H10 added samples, the average crystallite size increases after cold pressing because of the accumulation and inhomogeneous distribution of C in the MgB2 structure while it reduces for the C16H10 added hot pressed sample. The resistivity measurements showed that the increment of electron scattering is higher for the C16H10 added cold pressed sample than that of the C16H10 added hot pressed one which shows relatively better grain connectivity, and the Tc values of the samples are not appreciably affected by the pressing conditions. From the magnetisation measurements the in-field Jc values at 10 K and 5.5 T were obtained as 8.41 × 103 A/cm2, 1.62 × 104 A/cm2, 6.90 × 103 A/cm2 and the Hirr values while Jc = 100 A/cm2 at 20 K were obtained as 5.99 T, 6.55 T and 6.19 T for the pure sample and the C16H10 added hot and cold pressed samples, respectively. The higher Jc and Hirr values obtained for the C16H10 added hot pressed sample is because of the homogenous C substitution into MgB2 grains, as compatible with its lower Δρ value, and thus increased flux pinning ability.
- MakaleAçık Erişim2024Scopus SJRQ1Analysis of optical, structural, and morphological properties of a Ti-doped α-Fe2O3 thin film produced through RF and DC magnetron Co-sputtering
Abdolahpour Salari, Maryam; Merhan Muğlu, Günay; Şenay, Volkan; Sarıtaş, Sevda; Kundakçı, Mutlu
In this study, a Titanium (Ti) doped α-Fe2O3 (hematite) thin layer was synthesized onto a glass substrate, employing the simultaneous DC and RF magnetron sputtering method. The investigation focused on examining specific physical properties of the film. The optical, structural, morphological, and elemental features of the resulting Ti-doped α-Fe2O3 thin film were characterized using different characterization techniques. The XRD studies indicated a rhombohedral crystal structure in the studied thin film. The calculation of the Eg value for the thin film, based on absorption measurements, resulted in a value of 2.19 eV. Raman peaks were identified within the range of 218 cm−1 to 1300 cm−1. According to SEM images, the thin film exhibited a uniform surface morphology across the substrate. AFM images revealed a low root mean square (RMS) roughness value, indicating a smooth Ti:Fe2O3 thin film surface.
AtıfScopus24WoS25OpenAlex29İncele - MakaleYalnız künye2024Scopus SJRQ1The effect of nurse-led motivational interviewing based on the trans-theoretical model on promoting physical activity in healthy older adults: A randomized controlled trial
Sönmez Sari, Ebru; Kitiş, Yeter
Aim: The aim of this study was to evaluate the effect of motivational interviewing based on the trans-theoretical model promoting physical activity in older adults. Methods: A randomized controlled trial study was conducted with 117 older adults (intervention group: 58, and control group: 59) between April and November 2019. The data were collected via a questionnaire, trans-theoretical model scales, the Physical Activity Scale for the Elderly, the Katz Activities of Daily Living scale and a pedometer. The 24-week intervention consisted of regular motivational interviewing. The control group received usual care at the family health centre. Results: Following the intervention, the Intervention Group showed significant improvements Exercise Processes of Change Scale, Exercise Self-Efficacy Scale and Perceived Benefits of the Decisional Balance Scale for Exercise. There was a significant difference between the groups in terms of stages of change. In the Intervention Group, 81.5% were in the contemplation stage in the pre-test, while in the post-test, 70.4% had transitioned to the action stage. In contrast, in the control group, 62.5% were in the contemplation stage initially, but in the post-test, only 9.3% had reached the action stage. The mean number of step counts increased significantly in favour of the Intervention Group, as did the Physical Activity Scale for the Elderly total score. Conclusion: The trial indicated that after the trans-theoretical model-based motivational interviewing, the stages of change among the older adults improved, as did their exercise behaviours. It is recommended that the trans-theoretical model and motivational interviewing be used by nurses to improve healthy lifestyle stage behaviours in older adults.
AtıfScopus14WoS12OpenAlex12İncele - MakaleAçık Erişim2024Scopus SJRQ2An optimization study for amino acid extraction from bee bread using choline chloride-acetic acid deep eutectic solvent and determination of individual phenolic profile
Kutlu, Naciye; Gerçek, Yusuf Can; Çelik, Saffet; Bayram, Sinan; Ecem Bayram, Nesrin
In this study, the aim was to optimize the extraction conditions (molar ratio, time, temperature) in order to maximize the total individual amino acid (TAA) yield from bee bread, which is a fermented bee product, using choline chloride-acetic acid deep eutectic solvent (DES). In addition to the phenolic profile and amino acid profile investigated by LC-MS/MS, some spectrophotometric (total phenolic content, total flavonoid content, total proanthocyanidin content) and bioactivity (antioxidant/antimicrobial activity) tests were carried out on the extracts. Optimum conditions were determined as 1:2 for molar ratio, 15 min for time and 10 °C for temperature with optimization based on the TAA values of the different extracts (d: 0.99). Molar ratio and temperature were found to have statistically significant effects on TAA values. At optimum conditions, the amount of TAA obtained with DES (29.678 g/kg) was found to be approximately 35.2% and 54.4% higher than that obtained with ethanol and methanol extracts, respectively. All these results indicate that choline chloride-acetic acid DES can be chosen when preparing bee bread extracts, which are evaluated for different areas of use such as food and health due to active ingredient content. Higher active ingredients can be extracted by trying different DES combinations.
AtıfScopus7WoS9OpenAlex11İncele - MakaleYalnız künye2024Scopus SJRQ1A Novel Fuzzy Cumulative Sum Control Chart with an α-Level Cut Based on Trapezoidal Fuzzy Numbers for a Real Case Application
Özdemir, Akın; Uçurum, Metin; Serencam, Hüseyin
Statistical process control (SPC) is widely used to monitor production processes in many industries under certain conditions. When dealing with a quality characteristic for uncertainty, fuzzy numbers are used in the context of the statistical process control (SPC) to monitor a fuzzy production process. The aim of this paper is fourfold. One, a fuzzy X¯-R control chart with an α-level cut is used based on trapezoidal fuzzy numbers (TFNs) for detecting the large shifts in the fuzzy process mean. Second, a fuzzy cumulative sum (FCUSUM) control with an α-level cut based on TFNs is firstly developed for detecting the small shifts in the fuzzy process mean. Third, the fuzzy process capability indices (FPCIs) are presented to measure the fuzzy process performance. Finally, an ultra-fine calcite production process is controlled with both the fuzzy X¯-R control chart and the proposed FCUSUM control chart. The results of the fuzzy X¯-R control charts show that the fuzzy production process is in control, and large shifts in the fuzzy process mean were detected. On the other hand, the results of the FCUSUM charts show that the fuzzy production process is out of control, and small shifts in the fuzzy process mean were detected. FPCIs are also conducted, and the results of fuzzy Cpk indices show that the ultra-fine calcite production process is not capable of meeting specification limits.
AtıfScopus7WoS9OpenAlex9İncele - MakaleAçık Erişim2024Scopus SJRQ1An investigation of cyberloafing behaviors in learners of Turkish as a foreign language
Güngör, Haluk; Ustabulut, Mete Yusuf
Cyberloafing can be defined as using technological devices for extracurricular activities during the lesson. The misuse of technological tools and facilities in educational environments causes many learning problems. One of the most important behaviors that cause this problem is cyberloafing. The explorative and main aim of the current study is to examine the reasons behind the cyberloafing behaviors of those who learn Turkish as a foreign language in terms of various variables and explore the phenomenological point of view of participants. The research was carried out in accordance with the convergent parallel mixed method design. The “Cyberloafing Behaviors Scale” was employed to collect quantitative data from a total of 207 students learning Turkish in 5 different TÖMER (Teaching Turkish Center); in the process of qualitative data collection, open-ended questions formed by the researcher were used. For examining mean differences in terms of categorical variables t-test and separate ANOVAs were run. In ANOVAs, in order to minimize the possibility of error that may occur in the ANOVA test, type I error was controlled with Bonferroni correction. To determine predictors of cyberloafing behaviors of the study group multiple regression analysis was utilized. According to the findings of the current study, there was no significant difference between gender and time spent on social media and cyberloafing behavior; in the real-time updating dimension, it was determined that there was a significant difference between the B1 level and B2 and C1 levels. Having devices such as laptops stands out as the variable that predicts cyberloafing the most. It was also observed that cyberloafing behavior decreased as speaking skill increased. When the qualitative data was examined, the students stated that they were cyberloafing due to reasons such as messaging, sharing photos and videos because of boring lessons.
AtıfScopus3WoS4OpenAlex4İncele - MakaleAçık Erişim2024Scopus SJRQ3Nonlinear optical response of LinClK (n = 1–6) superalkali clusters
Şentürk, Şükrü; Ekincioğlu, Yavuz; Doğan, Ümit
The geometrical structures, stabilities, electronic properties and nonlinear optical response of the halogen doped bimetallic LinClK (n = 1–6) clusters were studied within the density functional theory. Based on the dissociation energy, second order energy difference and GH-L (HOMO-LUMO gap), the LinClK (n = 2, 4, 6) clusters are more stable. According to their ionization energies, the clusters can be classified as a superalkali. From the NBO analysis, the clusters are excess electron systems. The obtained first static hyperpolarizability (o) values are in the range of 1.56 × 104 − 4.33 × 104 au while the second static hyperpolarizability vary within 2.47 × 106 au to 13.9 × 106 au for the LinClK (n = 1–6) superalkalis that are slightly higher than the nonlinear optical response of halogen doped monometallic clusters. More importantly, the Li5ClK is transparent in the deep UV region ( < 300 nm) among the superalkalis indicating that the Li5ClK superalkali can be a candidate structure as new member of NLO materials.
AtıfScopus1WoS1OpenAlex1İncele - Derleme MakaleAçık Erişim2024Scopus SJRQ1Oxidative stability, quality, and bioactive compounds of oils obtained by ultrasound and microwave-assisted oil extraction
Walayat, Noman; Yurdunuseven-Yıldız, Aysun; Kumar, Manoj; Goksen, Gulden; Öztekin, Sebahat; Lorenzo, José Manuel
Vegetable oils are extracted from oilseeds, fruits and other parts of plants. The method used in oil extraction is of great importance, as it affects both the quality of the final product and the environment. It is desirable that the extraction method be minimally costly, fast, environmentally friendly, and produce oil of high quality and quantity. Common oil extraction methods are mechanical pressing and solvent extraction, and these methods have advantages and disadvantages over each other. Mechanical extraction and solvent extraction are controversial due to poor product quality and high environmental impacts. This review presents applications where conventional oil extraction processes are assisted by microwave or ultrasound. It is necessary to evaluate the impact of ultrasound and microwave-assisted extraction on the quality of the extracted oil and also to compare the results with those of conventional extraction methods. For this purpose, this review discusses the effects of microwave and ultrasound-assisted extraction on the physicochemical, oxidation indices, bioactive compounds, and antioxidant properties of oil extracted from oil seeds and fruits. Furthermore, this review provides readers with in-depth information on the mechanisms involved, their use, and the impact of operating conditions. The yield and quality of the oil obtained by these processes can vary depending on parameters such as microwave power, ultrasound power, processing time, and temperature. Finally, the review also discusses the challenges and advantages of the industrial application of these technologies.
AtıfScopus47WoS41OpenAlex45İncele - MakaleAçık Erişim2024Scopus SJRQ3The relationship between parental awareness of sexual abuse and children's skills to say «no»; [Relación entre la conciencia de madres y padres sobre el abuso sexual y las habilidades de los niños para decir «no»]
Kirbaş, Zila Özlem; Şahin, Emel
Introduction: Child sexual abuse is a global and multidimensional social problem and causes devastating and permanent psychological, emotional, cognitive, behavioural, physical, sexual and interpersonal sequelae. This study examines the relationship between the ability to say «no» and parental awareness of sexual abuse in 4th grade primary school students. Methods: The study was conducted between April 2022 and June 2022 in primary schools in the central district of a province in north-eastern Turkey. The sample consisted of 310 students enrolled in 4th grade and their parents. We collected the data through a personal information form, the ability to say «no» scale for children and the sexual abuse awareness scale for parents. Results: There was a weak positive correlation between the mean maternal scores of sexual abuse awareness and the mean scores of refusal and resistance in children (P ˂ .05), as well as a weak positive correlation between the mean paternal scores of sexual abuse awareness and the mean scores of refusal and resistance in children (P ˂ .05). Conclusion: As mothers’ and fathers’ awareness of sexual abuse myths and of teachings and actions to combat sexual abuse increased, the refusal of children also increased. Also, as fathers’ awareness of the signs of sexual abuse increased, children's refusal increased.
AtıfScopus3WoS2OpenAlex3İncele - Derleme MakaleAçık Erişim2024Scopus SJRQ1Quality and stability of frying oils and fried foods in ultrasound and microwave–assisted frying processes and hybrid technologies
Yildiz, Aysun Yurdunuseven; Echegaray, Noemí; Öztekin, Sebahat; Lorenzo, José Manuel
Frying is a popular cooking method that produces delicious and crispy foods but can also lead to oil degradation and the formation of health-detrimental compounds in the dishes. Chemical reactions such as oxidation, hydrolysis, and polymerization contribute to these changes. In this context, emerging technologies like ultrasound-assisted frying (USF) and microwave (MW)-assisted frying show promise in enhancing the quality and stability of frying oils and fried foods. This review examines the impact of these innovative technologies, delving into the principles of these processes, their influence on the chemical composition of oils, and their implications for the overall quality of fried food products with a focus on reducing oil degradation and enhancing the nutritional and sensory properties of the fried food. Additionally, the article initially addresses the various reactions occurring in oils during the frying process and their influencing factors. The advantages and challenges of USF and MW-assisted frying are also highlighted in comparison to traditional frying methods, demonstrating how these innovative techniques have the potential to improve the quality and stability of oils and fried foods.
AtıfScopus35WoS33OpenAlex39İncele - MakaleAçık Erişim2024Scopus SJRQ1FR2/mmWave, N258 and N261 Bands, 5G Frequency-Compatible Ultra-Thin Metamaterial Absorber with Polarization Insensitivity for EMI shielding Applications
Teber, Ahmet
Since adopting 5G technology, a notable rise in the prevalence of electromagnetic (EM) waves in the environment has become a significant concern. To reduce EM interference, broadband metamaterial absorbers offer an alternative solution for protecting devices in defense, communication, and healthcare applications, unlike their narrowband counterparts. This article presents a numerical investigation of an ultra-thin, polarization-insensitive metamaterial absorber (MMA) that uses metasurfaces and provides electromagnetic interference (EMI) reduction, covering the FR2/mmWave licensed N258 and N261 bands with an oblique incidence angle of up to 15 degrees. Comprehensive simulations are performed within the CST Studio Suite S2 2023 to examine the absorber's performance. Under normal incidence, the proposed MMA exhibits a wideband absorbency response exceeding 90% within the frequency range of 24.30–28.12 GHz. Moreover, the physical absorption mechanism is explained with electric and magnetic field distributions, including surface current distributions. Confirmation of the lack of mutual interaction among neighboring unit cells is established through testing with 1 × 2 and 2 × 2 arrays. An equivalent circuit model is also developed to confirm the EM simulation findings. The notable features of the proposed MMA make it an exceptional candidate for EM shielding applications, providing EMI reduction and covering the N258 and N261 bands.
AtıfScopus7WoS3OpenAlex5İncele - MakaleAçık Erişim2024Scopus SJRQ3Machine learning driven optimization and parameter selection of multi-surface HTS Maglev
Ozkat, Erkan Caner; Abdioglu, Murat; Ozturk, U. Kemal
This research aims to tackle the challenges posed by precise force measurement for high temperature superconducting (HTS) Maglev systems, including mechanical constraints, step motor limitations, and sensor resolutions. For this aim, six machine learning (ML) models namely Support Vector Machine (SVM), Gaussian Process Regression (GPR), Extreme Gradient Boosting (XGB), Long Short-Term Memory (LSTM), Extreme Machine Learning (EML), and Convolutional Neural Network (CNN) were developed to predict levitation force (Fz) and lateral force (Fx) based on process parameters including permanent magnet width (PMW), field cooling height (FCH), the movement in the z-axis (vertical distance), and the movement in the x-axis (lateral distance). Among six ML models, CNN emerged as the most accurate model, demonstrating smaller root mean square deviation (RMSD) without compromising correlation coefficients. Furthermore, an innovative process window approach was introduced to select process parameters that simultaneously meet the minimum value of Fz and maximum value of Fx, named β1 and β2, set at 90 N and 0 N, respectively. Within this window, PMW of 30 mm and z values less than 10 mm were found to be consistent for all FCH and x values. The novelty of this study is to formulate the optimisation problem in HTS Maglev using the developed ML model by addressing two specific objectives one of which focuses on maximizing Fz while ensuring Fx remains within a defined tolerance (β3), representing the minimum allowable ratio of the levitation force to the total force, and the second problem aims to maximize Fz while obtaining zero Fx. The optimum PMW, FCH, x, and z values were obtained at 30 mm, 30 mm, 4 mm and 5 mm, corresponding to Fz and Fx values of 224.2 N and -53.8 N for option 1. As for option 2, the process parameters were obtained as 28.6 mm, 25.9 mm, 0 mm, and 5 mm, corresponding to Fz and Fx values of 194.2 N and 0 N. It was obtained both experimentally and by the optimization that Fz reaches close its maximum as the Fx gains attractive character. Hence, it is expected that the outcomes of this study will significantly benefit the design of HTS Maglev systems and find valuable applications across various transportation engineering projects.
AtıfScopus21WoS18İncele - MakaleYalnız künye2024Scopus SJRQ1Research of the crack problem of a functionally graded layer
Yaylacı, Murat; Yaylacı, Ecren Uzun; Turan, Muhittin; Özdemir, Mehmet Emin; Öztürk, Şevval; Ay, Sevil
In this study, the two-dimensional crack problem was investigated by using the finite element method (FEM)based ANSYS package program and the artificial neural network (ANN)-based multilayer perceptron (MLP) method. For this purpose, a half-infinite functionally graded (FG) layer with a crack pressed through two rigid blocks was analyzed using FEM and ANN. Mass forces and friction were neglected in the solution. To control the validity of the crack problem model exercised, the acquired results were compared with a study in the literature. In addition, FEM and ANN results were checked using Root Mean Square Error (RMSE) and coefficient of determination (R2), and a well agreement was found. Numerical solutions were made considering different geometric parameters and material properties. The stress intensity factor (SIF) was examined for these values, and the results were presented. Consequently, it is concluded that the considered non-dimensional quantities have a noteworthy influence on the SIF. Also FEM and ANN can be logical alternative methods to time-consuming analytical solutions if used correctly.
AtıfScopus27WoS30OpenAlex6İncele - MakaleYalnız künye2024Scopus SJRQ1Effective biocatalytic synthesis of enentiopure (R)-1,2-diphenylethanol as a pharmaceutical precursor using whole-cell biocatalyst
Çakmak, Fadile; Özdemir, Akın; Dertli, Enes; Şahin, Engin
Optically active alcohols are crucial precursors. 1,2-Diarylethanols and their analogues constitute a significant group of substances of biological significance. The biocatalytic synthesis of (R)-1,2-diphenylethanol ((R)-2), which can be utilized as a precursor to important drugs, is still not at the desired level in terms of substrate amount and production process. This study asymmetrically reduced 1,2-diphenylethanone (1) using the Lactobacillus paracasei BD87E6 biocatalyst and a novel orthogonal quadratic design-embedded optimization approach. The following reaction optimization conditions were determined using the suggested optimization technique: pH = 6, temperature = 31 °C, incubation period = 48 h, and agitation speed=134 rpm. In addition, the reaction conversion was estimated to be 99.38 %, and the product's enantiomeric excess (ee) was estimated to be 99.12 %. Further, (R)-2 was produced with >99 % ee, >99 % conversion, and 98 % yield in the experimental investigation under the established optimum conditions. This study is the first attempt to reduce substrate 1 to (R) or (S)-2 using a mathematical optimization method in the presence of a biocatalyst. Furthermore, on a high-gram scale, 1 (15.70 g) was entirely transformed into (R)-2 (15.54 g, 98 % isolated yield). Notably, this study is also the first to perform the gram-scale production of (R)-2 using a novel optimization approach and a biocatalyst. Finally, the innovative and novel orthogonal quadratic design-embedded optimization technique has been demonstrated as an efficient, cost-effective, and environmentally friendly biocatalytic procedure for synthesizing (R)-2.
AtıfScopus7WoS7OpenAlex6İncele - MakaleAçık Erişim2024Scopus SJRQ1Virtual Reality Technology in Nursing Education: A Qualitative Study
Avşar, Gülçin; Çelik, Şeymanur; Doğan, Sevgi; Çiftçi, Bahar
Virtual reality (VR) technology plays a significant role in nursing education by enhancing the quality of training by applying knowledge, decision-making, intervention completion and feedback. This study aims to examine nursing students' experiences and perceptions regarding the ventrogluteal injection training provided through VR technology. Conducted between May and June 2022, this qualitative descriptive phenomenology study took place at a state university in Turkey, involving 70 students who participated in Ventrogluteal Drug Administration training using VR glasses. The sample included 12 students selected via the Criterion Sampling Method. Data collection tools comprised the ‘Descriptive Information Form’ and a ‘Semi-Structured Questionnaire’. Qualitative data were analysed using the Content Analysis Method, while quantitative data were assessed through descriptive statistical methods (frequency, percentage, mean). The study identified 13 codes, four sub-themes and two main themes from the students' evaluations. The first main theme, ‘Weaknesses of Virtual Simulation’, included two sub-themes: ‘Due to its Nature’ and ‘Due to its Technique’, resulting in five codes. The second main theme, ‘Strengths of Virtual Simulation’, was divided into two sub-themes: ‘Permanence, Integrity, and Applicability’ and ‘Emotions towards Virtual Simulation’, with eight codes identified. The findings indicate that students view VR technology positively in their education. However, they also highlighted specific issues related to the simulation's technique and inherent nature.
AtıfScopus5WoS4OpenAlex6İncele