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ÜRETİMDE DİJİTAL İKİZLERİN KULLANIMI: ISO 23247 STANDARDI
No full textDigital twin is an Industry 4.0 technology that enables monitoring, optimizing, and error prediction of processes by providing continuous data flow and synchronization between physical and digital systems. Digital Twin (DT) technology plays an important role in monitoring and controlling Cyber-Physical Systems (CPS) and smart manufacturing processes. DTs, which are widely researched in both academic and industrial fields, are seen as a critical technology in smart manufacturing. In manufacturing environments, digital twin frameworks are often used in Product Lifecycle Management, machine tool cyber twins and robotic assembly applications, in many sectors such as security, construction, transportation and healthcare, to simplify product maintenance, reduce costs and increase safety standards. New models are supported by technologies such as Internet of Things (IoT) devices, sensor data, artificial intelligence and blockchain. Although the concept of digital twins has attracted great interest in academic and industrial fields, it poses some challenges, especially for small and medium-sized enterprises (SMEs). The most important of these challenges is that the terminology and application standards for digital twins are not yet fully established. For digital twins to be widely used in production, standardized definitions, common terminologies and application frameworks are needed. To address these needs, ISO 21597, developed by the International Organization for Standardization (ISO), provides data containers and connectivity, while ITU-T Y.3090 and ISO 23247 provide frameworks that support the process of creating digital twins. The ISO 23247 standard was published in 2020 by the ISO TC 184/SC 4 committee to support the development of digital twins in manufacturing applications. The standard provides a comprehensive architectural framework for the creation of digital twins and provides an adaptable structure for different types of manufacturing. It proposes a flexible structure based on existing standards and technologies, especially for modeling observable elements in manufacturing environments. The ISO 23247 standard proposes a reference architecture for digital twins in manufacturing, including an asset-based reference model and a functional perspective defined in terms of functional assets. Digital twins can be used for different purposes. DTs provide bidirectional and automatic data flow with physical systems, reflecting the current state of the system and predicting and optimizing performance. Discrete Event Simulation (DES) is a widely used technique for the analysis and optimization of industrial systems. DES models simulate the operation of real systems by monitoring the interactions between various events and the system state at discrete times. These traditional applications of simulation are based on creating a static model and performing analyses on it, and the model is usually retired after a single analysis. In this research, studies in the literature on the use of DTs in the Industry 4.0 and 5.0 process were examined. The lack of standards regarding the terms, architecture and models for DTs leads users to understand DTs differently when developing applications that enable DTs, making it difficult to connect data, models and services across different companies or domains. Therefore, developing DTs according to standardized reference architectures is a future necessity to ensure their adoption and facilitate their creation, processing and integration.Dijital ikiz, fiziksel ve dijital sistemler arasında, sürekli veri akışı ve senkronizasyon sağlayarak, süreçlerin izlenmesini, optimize edilmesini ve hata tahminini mümkün kılan bir Endüstri 4.0 teknolojisidir. Dijital İkiz (Dİ) teknolojisi, Siber-Fiziksel Sistemler (SFS) ve akıllı üretim süreçlerinin izlenmesi ve kontrol edilmesinde önemli bir rol oynamaktadır. Hem akademik hem de endüstriyel alanda yaygın olarak araştırılan Dİ'ler, akıllı üretimde kritik bir teknoloji olarak görülmektedir. ISO 23247 standardı, üretimde dijital ikizler için varlık tabanlı bir referans modeli ve işlevsel varlıklar açısından tanımlanan işlevsel bir bakış açısını içeren bir referans mimari önermektedir. Bu araştırmada, Dİ'lerin, Endüstri 4.0 ve 5.0 sürecinde kullanımı ile ilgili literatürde yapılan çalışmalar incelenmiştir. Dİ'ler için önerilen ISO 23247 standardı açıklanmış ve kullanımı ile sağladığı katkılar araştırılmıştır. Dijital İkizler 'in araştırma ve sanayide, otomotiv, biyoloji, tıp ve üretim gibi birçok alanda Siber-Fiziksel Sistemleri izlemek ve kontrol etmek için kullanıldığı çalışmalar analiz edilmiştir. Dİ'lerin Siber-Fiziksel Üretim Sistemleri'ni iyileştirmek için kullanıldığı belirlenmiştir. Dijital ikizlerin, karmaşık durumlarda karar destek aracı olarak kullanılabileceği, gerçek sistem davranışını tahmin edebileceği ve çözüm arayışlarında yardımcı olabileceği belirlenmiştir. Dijital ikizlerin, sistemlerin gelecekteki durumlarını anlamak için gerekli veriyi sağlayabilmesi ve sanal sistemle gerçek sistemi senkronize edebilmesi gerektiği tespit edilmiştir. Dijital ikizler, otomasyonun yüksek olduğu ortamlarda daha etkili uygulanabileceği gözlemlenmiştir
SnO2/MgF2 anti-reflection coatings for optical glass: design, optimization and simulation approaches
No full textThis study investigates the design, optimization, and simulation of anti-reflection (AR) coatings for optical glass, focusing on reducing reflectance and enhancing light transmittance across the ultraviolet (UV) and visible spectrum. By employing Ray-Tracing simulation techniques, various thin-film configurations-including single-layer, double-layer, four-layer, and two-layer coatings-were analyzed for their optical properties. These coatings were applied to the glass to determine the most effective combinations for minimizing light reflectance and optimizing visual performance. SnO2 and MgF2 were selected as the coating materials due to their complementary refractive indices, which are crucial for reducing reflectance across a wide wavelength range. The simulation results revealed that bilayer coatings on both sides of the glass outperformed other configurations, particularly at the critical wavelength of 550 nm, where human visual sensitivity peaks. This wavelength-specific optimization is essential for reducing glare and improving the visual clarity of optical surfaces, making these coatings highly applicable in products such as eyeglasses and precision optical instruments. The findings underscore the potential of SnO2/MgF2 coatings in achieving high optical performance, providing a foundation for future developments in anti-reflective technologies aimed at improving visual comfort and clarity
The Relationship Between Preoperative Anxiety Levels of Patients Undergoing Total Knee Arthroplasty and Postoperative Recovery
No full textPurpose: Surgical interventions are significant factors that cause anxiety in individuals. This study aimed to determine the effect of preoperative anxiety on postoperative recovery in patients undergoing total knee arthroplasty. Design: A cross-sectional and correlational study. Methods: This study was conducted between February 2023 and September 2023 with 204 patients scheduled for total knee arthroplasty. Data were collected through face-to-face interviews using the Patient Information Form, Surgical Anxiety Questionnaire for Adult Patients, and Postoperative Recovery Index (PRI). Findings: The Surgical Anxiety Questionnaire for Adult Patients' mean score was 31.38 ± 13.91 and the PRI total score was 2.98 ± 0.76. The subscale showed that the highest scores were 12.14 ± 4.97 for health-related anxiety. The anxiety scores concerning recovery, surgical procedures, and invasive procedures were lower. Patients experienced moderate difficulty in the recovery of intestinal symptoms (2.55 ± 0.98) and psychological symptoms (2.43 ± 0.88), significant difficulty in the recovery of desire-wish symptoms (>2.5), and extreme difficulty in the recovery of physical symptoms (3.87 ± 0.81). A positive and statistically significant relationship was found between surgical anxiety levels and postoperative recovery index mean scores (P < .001). Conclusions: The study showed that preoperative surgical anxiety negatively impacts postoperative recovery. Identifying preoperative anxiety levels and implementing interventions to reduce or eliminate surgical anxiety will be beneficial in achieving positive outcomes in the postoperative recovery process. © 2025 Elsevier B.V., All rights reserved
Effect of Si and Cr on formation of aluminide coatings on Ti6Al4V alloy by low temperature aluminizing: Wear and oxidation behavior
No full textTo improve the surface properties of the Ti-6Al-4 V titanium alloy, TiAl3-based intermetallic coatings were produced at 710 degrees C-4 h via a low-temperature aluminizing process. Additionally, Si and Cr were incorporated into the Ti-Al coating to investigate their effects on the properties of the Ti-Al system. The findings revealed that the coatings formed strong metallurgical bonds with the substrate, and no significant cracks were detected in the Ti-Al system coatings. However, the addition of Cr was found to have a negative effect on the growth of the coating layer. Similarly, the simultaneous addition of Cr and Si reduced the thickness of the layer from 14 mu m to 5 mu m. An increase of up to 248 GPa elastic modulus (EIT) and 10.36 GPa hardness was achieved with the aluminide coating of Ti6Al4V, which have had 150 GPa EIT and 5.56 GPa hardness. While all coatings provided better wear performance compared to the substrate, the lowest volume loss was observed in the TiAl coating with the highest thickness. Similarly, the best oxidation resistance was obtained in TiAl due to higher coating thickness and lower phase transformation in its coating layer compared to others. The addition of Si and Cr did not affect the formed oxide products, but they decreased the oxidation resistance due to thinner coating structure
Effects of Perceived Trauma Levels of Women at Reproductive Age after Earthquakes on Their Menstruation Cycle
No full textObjective The purpose of this study is to determine the effects of the perceived trauma levels of women at reproductive age after earthquakes on their menstruation cycle.Methods This descriptive and correlational study was conducted between March 17, 2023, and April 17, 2023, after the earthquakes that happened in Turkey on February 6, 2023 and affected 11 cities. The study was conducted with 355 women. Data were collected using an online questionnaire form prepared via Google Forms. Data collection was performed using a Participant Information Form and the Post-Earthquake Trauma Level Determination Scale.Results According to the multiple regression analysis results, the significant predictors of perceived trauma levels after the earthquakes included the severity of dysmenorrhea (beta-coefficient = 0.164, P = .007), characteristics of vaginal discharge (beta-coefficient = 0.136, P = .027), and itching in the perineum (beta-coefficient = -0.220, P = .001). These variables explained 12.4% of the total variance in the perceived trauma levels of the participants.Conclusions The perceived trauma levels of women after the earthquakes had significant effects on the severity of dysmenorrhea, characteristics of vaginal discharge, and itching in the perineum. Health professionals should not overlook the effects of women's perceived trauma levels on their menstruation cycles after earthquakes and evaluate the issue considering these aspects
Forest Aboveground Biomass Estimation in Küre Mountains National Park Using Multifrequency SAR and Multispectral Optical Data with Machine-Learning Regression Models
No full textAboveground biomass (AGB) is crucial in forest ecosystems and is intricately linked to the carbon cycle and global climate change dynamics. This study investigates the efficacy of synthetic aperture radar (SAR) data from the X, C, and L bands, combined with Sentinel-2 optical imagery, vegetation indices, gray-level co-occurrence matrix (GLCM) texture metrics, and topographical variables in estimating AGB in the K & uuml;re Mountains National Park, T & uuml;rkiye. Four machine-learning regression models were employed: partial least squares (PLS), least absolute shrinkage and selection operator (LASSO), multivariate linear, and ridge regression. Among these, the PLS regression (PLSR) model demonstrated the highest accuracy in AGB estimation, achieving an R2 of 0.74, a mean absolute error (MAE) of 28.22 t/ha, and a root mean square error (RMSE) of 30.77 t/ha. An analysis across twelve models revealed that integrating ALOS-2 PALSAR-2 and SAOCOM L-band satellite data, particularly the SAOCOM HV and ALOS-2 PALSAR-2 HH polarizations with optical imagery, significantly enhances the precision and reliability of AGB estimations.Hacettepe University Scientific Research Projects Coordination Unit; [FDK-2022-20004]This article is part of the Ph.D. thesis research of the first author. The project was supported by the Hacettepe University Scientific Research Projects Coordination Unit with the project code FDK-2022-20004
Gastronomi Turizmi Kapsamında Bartın’daki Restoranlara Yapılan Çevrimiçi Yorumların İncelenmesi (Investigation of Online Comments on Restaurants in Bartın within the Scope of Gastronomy Tourism)
No full textÇevrimiçi yorumlar turizm destinasyonlarını değerlendiren turistler için kolay erişilebilir bir bilgi kaynağıdır. Bu değerlendirmeler, turistlerin gerçek deneyimlerini ve görüşlerini yansıtmaktadır. Bu çalışmanın amacı, gastronomi turizmi kapsamında Bartın’da faaliyet gösteren yiyecek içecek işletmelerini ziyaret eden turistlerin çevrimiçi değerlendirmelerini incelemektir. Nitel olarak tasarlanan bu çalışmada verilerin toplanmasında doküman incelemesi yöntemi kullanılmıştır ve ulaşılan veriler içerik analizi yöntemiyle incelenmiştir. Bu kapsamda TripAdvisor sitesinde en fazla yorumuna sahip beş işletme araştırmaya dahil edilmiştir. Toplamda 384 yoruma ulaşılmıştır ve bunların 247'si olumluyken, 137'si olumsuz yorumlardan oluşmaktadır. Araştırma kapsamında restoranlara yönelik yapılan değerlendirmeler yemek, hizmet, değer ve atmosfer temaları altında gruplandırılmıştır. Çalışmanın sonucuna göre, turistler genel olarak yemeklerin lezzetli olduğunu, hizmet kalitesinin yüksek olduğunu ve restoranların iyi bir atmosfere sahip olduğunu belirtmiştir. Fakat, bazı turistlerin yemeklerin kalitesi, porsiyonların azlığı, servisin yavaş olması ve personel davranışları konusunda olumsuz deneyimler yaşadığı belirlenmiştir. Restoranların, hizmet kalitesini artırmak ve olumsuz geri bildirimleri azaltmak için personel eğitimine ve servis hızına odaklanmaları önerilmektedir. Ayrıca, yemek porsiyonları ve fiyat politikası konusunda dengeli bir yaklaşım benimsemeleri turist memnuniyetini arttırabilir
Study of the Wear Resistance Plasma Nitrided GGG60 by Optimization of Surface Treatment Conditions Using Response Surface Methodology
No full textIn this study, the wear performance of spheroidal graphite cast iron subjected to plasma nitriding at different temperatures and treatment durations was investigated. The plasma nitriding parameters were optimized by response surface methodology (RSM) due to the output performance. Plasma nitriding was applied at three different temperatures (400, 450, 500 degrees C) and three different heat treatment durations (0.5, 2, 4 h). Wear tests were performed by ball-on-disk method for 60 minutes and for three different wear loads (10, 20, 30 N). The specimens were investigated for hardness, microstructure and wear performance. The RSM model was then created by using the wear resistance features. Plasma nitriding showed better wear performance than the untreated specimen for all treatment conditions. Hardness, nitrided layer thickness and wear performance remarkably improved with increasing temperature and process duration. The parameter that affects volume loss the most is wear load with 70.66% according to RSM modeling results. The most effective parameter in the wear rate change was found to be treatment duration at 42.85%. The model was able to predict the results with an error of 2.11% for volume loss and 9.14% for wear rate. The prediction results are very close to the experimental results. This clearly shows that the model can be used to determine the plasma nitriding parameters.Karabuk University Scientific Research Projects Coordination Unit [KBUBAP-23-YL-037]This work was supported by the Karabuk University Scientific Research Projects Coordination Unit. Project Number: KBUBAP-23-YL-037. The support is gratefully acknowledged
Experimental and computational analysis of benzothiophene as a selective inhibitors of diabetes mellitus
No full textDiabetes mellitus results in chronic hyperglycemia, affecting more than one hundred million people over the world. To treat diabetes mellitus, novel benzothiophene-derived thiadiazole analogues (1-17) were synthesized to biological assess their potential as lead inhibitors of both diabetic enzymes (alpha-amylase and alpha-glucosidase). These compounds showed quite remarkable potency against both enzymes and emerged as anti-diabetic agents. As a reference for their biological assessment, acarbose (5.90 +/- 0.30 mu M, 6.50 +/- 1.80 mu M) were used and in comparison to it analogue 3 having IC50 of 4.20 +/- 0.50 mu M, 4.90 +/- 1.50 mu M, 6 with IC50 of 3.10 +/- 1.20 mu M, 4.10 +/- 0.80 mu M, 10 with IC50 of 5.20 +/- 1.20 mu M, 6.10 +/- 2.10 mu M and 16 having IC50 of 3.90 +/- 2.20 mu M, 4.10 +/- 1.20 mu M emerged as most active analogues among the synthesized derivatives. Versatile attached functionalities such as CF3, F, OH and Cl bind with the target proteins in order to inhibit their normal activity or function. Binding potency (interactive properties) of the leading compounds was also revealed under molecular docking. ADME analysis further unveiled that the potent compounds exhibit drug properties. Moreover, reactivity of these analogues with leading potential was also explored via density functional theory (DFT), revealing their molecular electrostatic potential, electrophilic, nucleophilic, HOMO and LUMO sites.King Saud University, Riyadh, Saudi Arabia [RSPD2025R812]The authors extend their appreciation to the Researchers Supporting Project number (RSPD2025R812) , King Saud University, Riyadh, Saudi Arabia, for funding this work
Haar Wavelet Method for the Solution of Fourteenth Order Boundary Value Problems
No full textHigher-order boundary value problems (BVP) of differential equations (DEs) are important in the mathematical description of many real-world processes. Solving such problems for exact or analytical solutions is not always easy to deal. Therefore, to compute their numerical solution, we need some numerical methods. Hence, in this work, a powerful numerical procedure based on Haar Wavelet (HW) method is established to deal with fourteenth-order BVPs linear and nonlinear. A generalized form of the algorithm is developed under general boundary conditions. Then the numerical method is verified on various examples from the literature. Also, maximum and root mean square errors are calculated. Moreover, a comparison between exact and numerical results is shown at different collocation points. Furthermore, convergence rate is approximately 2 at various numbers of nodal points is also calculated