Hakkari Üniversitesi Akademik Veri Yönetim Sistemi
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A Review: Literature Summary on the Relationship Between Cutting Parameters and Machinability in Turning Operations
No full textThis study presents a comprehensive evaluation of machinability in turning operations by reviewing and synthesizing the literature based on the parameters of cutting forces, tool wear, and surface roughness. Previous studies clearly present the significance of cutting parameters. While an increase in speed mainly reduces the forces and roughness, increases in feed and depth tend to increase cutting forces, temperature, and wear by enlarging the contact area. Tool wear directly affects the surface integrity and process stability through flank/crater wear and BUE formation. In particular, austenitic stainless steels, titanium and nickel-based superalloys, and particle-reinforced composites are sensitive to the cutting mechanism, tool-material interaction, and speed. Environmentally sustainable cooling-lubrication strategies (MQL, plant-based oils, cryogenic/CO₂-based solutions) reduce wear by reducing friction and temperature, improving the surface quality. In the case of ultrasonic turning, similar benefits are provided by reducing instantaneous contact and average forces. In the examined studies, dynamometers, scanning electron microscopes, surface roughness measurement instruments, and various software were used. Additionally, optimum parameter windows were reported based on Taguchi/ANOVA/RSM methods. Consequently, the combination of appropriate parameter selection and environmentally friendly cooling and lubrication and/or auxiliary processes extends tool life, improves surface integrity, and increases energy and cost efficiency. This approach offers a repeatable and industrially applicable roadmap, even for materials that are difficult to machine.</jats:p
Prevalence of intestinal parasites in school-age children in Turkey: A systematic review and meta-analysis
No full textBackground Intestinal parasites are a major public health problem worldwide, especially in societies with low socioeconomic status and where sanitation rules are not sufficiently emphasized. School-age children are the most affected group in these societies. In light of the literature data, the intestinal parasites detected in school-age children and the geographical and socioeconomic structure of Turkey are evaluated together. The study hypothesizes that the parasite prevalence in school-age children is high, and there is substantial socioeconomic and geographical variation in speciesspecific prevalence. It is aimed to determine the pooled prevalence of intestinal parasite infections in school-age children in Turkey, identify the common parasite species, and compare the prevalence in different geographical regions of Turkey. Methods The Web of Science, PubMed, Scopus, and TR index databases were searched to access published articles reporting the presence of intestinal parasites among school-age children in Turkey. The prevalence of intestinal parasites was calculated using a random effects model. Subgroup analyses were performed according to the parasite species and geographical regions of Turkey. Also, year-based metaregression analyses were conducted. Results A total of 204.754 samples from 99 articles were included in the analysis. The pooled prevalence of intestinal parasites was 29%, with high heterogeneity (I2 = 99.88%, P < 0.001). The subgroup analysis revealed that the Southeastern Anatolia is the region with higher prevalence of intestinal parasites among school-age children, with a rate of 41% (I2 = 99.44%, P < 0.001). Subgroup analysis for parasite species revealed that G. intestinalis/duedonalis/labmblia (11%; 95% CI: 9%-13%, I2 = 99.85) was the most frequently detected parasite in school-age children, followed by Blastocystis spp., Enterobius vermicularis, Entamoeba coli, Ascaris lumbricoides and Entamoeba histolytica/dispar. Conclusion The prevalence of intestinal parasitic infections (IPI) among school-age children in Turkey is particularly high in Southeastern Anatolia, the Mediterranean, and Eastern Anatolia. Socioeconomic conditions, education, and geography are the main factors that affect this situation. It is crucial for school-age children and their parents to receive education on the transmission mechanisms of intestinal parasitic infections (IPIs) and strategies for their prevention. Furthermore, it is essential for local governments and public authorities to upgrade infrastructure to ensure that drinking water and food are not contaminated by polluted water sources
Sustainable Banking Through Corporate Social Responsibility: Financial and Emotional Pathways of Customer Perceptions—Evidence from Ankara, the Capital of Turkey
No full textIn the context of sustainable banking, this study examines the relationships between customers’ perceptions of corporate social responsibility (CSR), their evaluations of a bank’s financial performance, and the positive and negative emotions they associate with a bank, underscoring the importance of managing customer psychology. The dataset consists of 426 completed questionnaires collected from private bank customers in Ankara, the capital of Turkey. SPSS 24.0 was used for data entry, and SPSS and AMOS 24.0 were employed for statistical analyses. The analytical procedures included preliminary analyses, confirmatory factor analysis, Harman’s single-factor test, common latent factor analysis, internal consistency, composite reliability, convergent and discriminant validity, Pearson correlation analysis, structural equation modeling, the Sobel test, and a bootstrap method with 5000 resamples. The findings indicate that customers’ perceptions of CSR have a significant and positive direct effect on their perceptions of a bank’s financial performance. In turn, perceived financial performance positively influences customers’ positive emotions and negatively influences their negative emotions. Moreover, perceptions of CSR affect emotional responses both directly and indirectly through perceived financial performance, enhancing positive emotions and reducing negative ones. In conclusion, within the proposed model, perceived financial performance functions as a partial mediating variable between CSR perceptions and customer emotions. These findings advance CSR scholarship by mapping its financial and emotional impact pathways in banking, yielding strategic insights for practitioners
Comparison Generalized Item Location Indices for Polytomous Items: A Monte Carlo Simulation Study
No full textGeneralized Item Location Indices (GILI) is a method that deals with the process of developing or selecting polytomous items based on a single value. This method converts multiple location indices obtained for polytomous items into a single indices. The purpose of this research is to examine the performance of GILI under different simulation conditions. For the study, how three different GILI (LImean -LImedian-LIIRF) change according to the number of categories (3, 5 and 7), location parameter (-2, -1, 0, 1 and 2) and sample size (200, 500 and 1000) were compared with a monte carlo simulation. According to the results, the LImedian was estimated with the highest error in all conditions. On the other hand, LImean and LIIRF produce similar error amounts for all conditions. Although LImean and LIIRF produce similar results at -1, 0 and +1 location levels, LImean makes more accurate predictions at -2 and +2 location levels. It was concluded that as the number of categories increases, the amount of error calculated in small samples increases. LImean -LImedian-LIIRF values, which are matched with the individual's ability in tests developed for different purposes and CAT applications, can be a good parameter for determining which item to choose next during the administration of the test. As a result, the fact that the proposed method is easier and faster will facilitate the practitioners in the item selection process.Generalized Item Location Indices (GILI) is a method that deals with the process of developing or selecting polytomous items based on a single value. This method converts multiple location indices obtained for polytomous items into a single indices. The purpose of this research is to examine the performance of GILI under different simulation conditions. For the study, how three different GILI (LImean -LImedian-LIIRF) change according to the number of categories (3, 5 and 7), location parameter (-2, -1, 0, 1 and 2) and sample size (200, 500 and 1000) were compared with a monte carlo simulation. According to the results, the LImedian was estimated with the highest error in all conditions. On the other hand, LImean and LIIRF produce similar error amounts for all conditions. Although LImean and LIIRF produce similar results at -1, 0 and +1 location levels, LImean makes more accurate predictions at -2 and +2 location levels. It was concluded that as the number of categories increases, the amount of error calculated in small samples increases. LImean -LImedian-LIIRF values, which are matched with the individual's ability in tests developed for different purposes and CAT applications, can be a good parameter for determining which item to choose next during the administration of the test. As a result, the fact that the proposed method is easier and faster will facilitate the practitioners in the item selection process.</div
Traces of Earthquake in Urartian Kef Fortress Urartu Kef Kalesi’nde Depremin İzleri
No full textThis study examines the seismic traces at Kef Fortress, built during the reign of Rusa II of Urartu (685–645 BCE), in comparison with findings from the fortresses of Ayanis, Karmir Blur, and Bastam, in order to investigate the strategies developed by Urartian architecture against seismic threats and the role of earthquakes in the kingdom’s collapse. Excavations initiated in 2021 at Kef Fortress have revealed destruction layers, collapsed fortification walls, and evidence of fire, indicating that the fortress was heavily damaged by a powerful earthquake in the mid-7th century BCE. Similar evidence has been documented in the temple collapses at Ayanis, wall fractures at Karmir Blur, and deformations of fortification walls at Bastam. The comparative analysis demonstrates that while Urartu employed earthquake-resistant techniques such as thick stone walls and solid foundations, these measures ultimately proved inadequate against large-scale seismic events. It is further suggested that the earthquakes during the reign of Rusa II accelerated the process of the kingdom’s decline by disrupting water management systems and weakening defensive structures. The study emphasizes that future geoarchaeological and radiocarbon dating research may provide supporting evidence for this hypothesis
