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A comparative study on the effects of different fillers on mechanical properties in welding of S355NL via FCAW-S and GMAW processes
No full textIn this study, the filler wire used in open-arc welding and the solid wires used in gas metal arc welding were comparatively investigated for the welding of S355NL material. Although both techniques are commonly employed in industrial applications, the decrease in the mechanical properties of joints processed in exposed areas using gas metal arc welding due to insufficient gas protection suggests that self-shielding flux-cored wire welding could be an alternative. Their shielding mechanisms and filler wire compositions differ significantly, potentially affecting the microstructure and its mechanical performance. This research analyzes and compares key mechanical properties, including ultimate tensile strength, impact toughness, and Vickers hardness, obtained from welded specimens prepared for each process. The influence of factors such as heat input and the composition of the filler wires and shielding methods on mechanical properties was critically evaluated. Main alloying elements, such as Aluminum in the flux-cored filler, and Manganese and Silicon in solid wires, lead to different microstructures and therefore different mechanical behaviors. The welds using solid wires demonstrated an impact toughness of 4-6 times greater than that of the flux-cored filler. On the other hand, the ultimate tensile strength of the joint welded with flux-cored filler was 583.4 MPa, while it was around 550-560 MPa in the joints welded with solid wires under gas protection. Moreover, in the absence of gas protection, the welded joint using solid wire did not provide an acceptable strength. Analysis and investigations led to the conclusion that self-shielded flux-cored arc welding could be a viable alternative to gas metal arc welding if sufficient gas protection is not achievable, but further precautions and studies would be necessary for applications requiring high impact toughness
Modeling a Location and Routing Problem for Mobile Lockers in Last-Mile Delivery With Horizontal Collaboration
No full textDue to the growth of e-commerce, promising last-mile delivery options have emerged to manage the rise in delivery frequency and small-volume deliveries. These delivery methods include mobile parcel lockers that are placed by electric vehicles, which enables customers to receive their packages at any time. This study presents a decision support model for enterprises that utilize mobile parcel lockers in last-mile delivery with pick-up and delivery under horizontal collaboration. The model aims to allocate parcel lockers and route the vehicles with the minimum cost, which encompasses the expenses associated with transportation and placement of the lockers, transportation of customer cargo, vehicle utilization, and payment of drivers. We propose an integer linear programming model for the location routing problem. We present an ILP-based decomposition heuristic and an iterative approach to larger-sized practical instances. A numerical analysis is conducted to see the cost and benefit of bilateral and trilateral collaborations in an illustrative case. According to the results, the total cost is reduced by up to 4.52% for companies in the trilateral collaboration scenario with single warehouses, and by up to 7.32% in the trilateral collaboration scenario with multiple warehouses. We examine the large problem sizes of up to 100 nodes to see the performance of the heuristic approaches compared to the model solutions. The two-stage heuristic achieves the optimal solutions for all instances with a node size 50 in a shorter solution time. The iterative approach allows us to deal with the problem complexity of instances with 75 and 100 nodes and yields 0.88% close solutions to the model on average
Sustainable Consumption Behaviors of Different Generations: A Qualitative Research
No full textThe current study aims to explore consumers' sustainable consumption behavior (SCB) patterns within the framework of 7Rs, namely Reduce, Reuse, Recycle, Respect, Rethink, Reflect, and Redistribute. Also, the study examined whether SCBs vary among Baby Boomers, Gen-Xs, Gen-Ys, and Gen-Zs. A series of in-depth interviews were conducted with 96 individuals, 24 representing each generation. The data were analyzed using Content Analysis. The analysis results verified the major themes of the 7Rs and revealed related sub-themes. Besides, a novel theme was unveiled and labeled as "Reproduce" as the 8th R, which is also verified for all generations. By investigating the sub-themes of the 8Rs, remarkable intergenerational differences were discovered. This research highlights the variety of understandings underpinning the SCBs among different generations and contributes to the existing literature by expanding the SCBs framework to the 8Rs with a more comprehensive qualitative approach focusing on highly diversified types of sustainable behaviors.</p
The Relationship Between Financial Behavior, Financial Mutuality, and Marital Satisfaction of Married Individuals: The Mediating Effect of Financial Well-Being
No full textFinancial mutuality and financial behavior play an important role in the lives of married individuals and, consequently, in the functioning of families. This study thus aims to ascertain whether there is a correlation between financial behavior, financial mutuality, financial well-being, and marital satisfaction among married individuals in T & uuml;rkiye. Additionally, it seeks to determine whether financial well-being is a mediating factor in the relationship between financial behavior, financial mutuality, and marital satisfaction. The study was conducted with 262 married heterosexual individuals (58.4% male, 41.6% female) from various districts of Ankara. The results of the correlation analysis showed a positive relationship between financial mutuality, financial well-being, marital satisfaction, income, education, and financial behavior. The results showed a positive relationship between financial well-being, marital satisfaction, education, and spouses' financial mutuality. The path analysis revealed that the direct effects of financial mutuality on marital satisfaction were significant, in contrast to the indirect effects mediated by financial well-being
Binary classification with Fuzzy-Bayesian logistic regression using Gaussian fuzzy numbers
No full textBinary classification is a critical task in pattern recognition applications in artificial intelligence and machine learning. The main weakness of binary classifiers is their sensitivity towards the imbalance in the number of observations in the binary classes and separation by a subset of features. Although various robust approaches are introduced against these issues, they need prolonged runtimes, limiting their applicability in artificial intelligence applications or for large datasets. In this study, we introduce anew binary classification framework called the fuzzy-Bayesian logistic regression, which incorporates robust Bayesian logistic regression with fuzzy classification using Gaussian fuzzy numbers. The proposed method improves classification performance while providing significant gains in computation time. We benchmark the proposed method with eight fuzzy, Bayesian, and machine learning classifiers using seventeen datasets. The results indicate that the fuzzy-Bayesian logistic regression outperforms all benchmark methods across all datasets in terms of six performance indicators. Moreover, the proposed method is shown to be significantly more efficient than its closest competitor, improving computational efficiency. The proposed method provides a promising binary classifier fora wide range of applications with its computational efficiency and robustness towards imbalance and separation issues in the data
Adölesan İdiyopatik Skolyozlu Bireylerde Subjektif Omurga Değerinin Hasta Bildirimli Sonuçlar ve Fonksiyonel Performans ile İlişkisinin İncelenmesi: Pilot Çalışma
No full textSerum Albumin-Creatinine Ratio and Anthracycline Cardiotoxicity in Patients with Cancer
No full textBackground: Several studies have suggested that the serum albumin-creatinine ratio (sACR) is a useful marker for the early risk stratification of patients with cardiomyocyte injury. This study aims to evaluate the relationship between sACR and anthracycline-related cardiotoxicity. Methods: This study included patients who had received anthracycline-based chemotherapy between 2014 and 2023 and had undergone baseline and follow-up echocardiography after the treatment. The level of sACR was calculated using serum albumin and creatinine values obtained before the chemotherapy. The definition of cardiotoxicity was based on the criteria of the European Society of Cardiology (ESC) for ejection fraction and the American Society of Echocardiography (ASE) for diastolic dysfunction. The patients were categorized into either the high or low sACR group based on the cut-off value obtained from the receiver operating characteristic (ROC) curve analysis. Results: In total, 525 patients (159 males, 366 females) were included. Multivariate analysis after adjustment for age, body mass index (BMI), cardiovascular disease, hemoglobin, anthracycline dose, and gender showed that sACR (HR = 1.85% 95 CI 1.12 to 3.06 p = 0.016), cardiovascular disease (HR = 1.97% 95 CI 1.08 to 3.61 p = 0.027), BMI (HR = 1.86% 95 CI 1.12 to 3.10 p = 0.017), and age (HR = 1.02% 95 CI 1.001 to 1.04 p = 0.036) were significantly associated with an increased risk of cardiotoxicity. Conclusions: This study is the first to show a significant relationship between sACR and cardiotoxicity related to anthracycline use. Routine laboratory tests that are conducted before anthracycline therapy can aid clinicians in identifying high-risk patients who may require closer follow-up or cardioprotective measures
