Özkan, O.; Destek, M.A.; Khan, Z.; Manga, M.

This study explores how oil efficiency and hydropower innovation affect carbon emissions in Japan. In this direction, the novel multivariate quantile on quantile regression technique is applied to explore the period from 2000 to 2020. In addition, to prevent omitted variable bias, the environmental implications of industrialization, urbanization, and economic growth are also observed. The empirical findings indicate that oil efficiency, industrialization, and hydropower innovations are all lower carbon emissions. However, urbanization and economic growth harm the environmental quality. Lastly, a robustness check is performed using a kernel-based regularized least squares technique based on machine learning. The results of this investigation support the claim that oil efficiency and hydropower innovation can reduce emissions. Furthermore, it is found that the emission-reducing impact of both gets stronger as the emission level rises.

Aygun, Z.; Astam, A.; Aygun, M.

The use of natural resources and waste products represents an effective way of addressing a pressing concern for the future of the global population. It is therefore crucial to evaluate wastes and natural materials as raw materials in many industries. The present study sought to investigate the radiation protection features and experimental characteristics of tincal waste added with obsidians from Eastern Turkey (Nemrut, Pasinler, Sarıkamış and Ikizdere regions). Fourier transform infrared spectrometry, X-ray diffraction, Scanning electron microscopy and Energy dispersive spectroscopy were used to have knowledge for morphological and structural properties of the samples. The X-ray diffraction analysis of the samples with higher obsidian content revealed an amorphous structure with a minor presence of crystalline phases. In contrast, the samples with a higher tincal waste content exhibited crystalline phases. Based on morphologic results, it can be said that obsidian samples exhibited relatively smooth and glassy surfaces, whereas tincal waste displayed a rough surface comprising randomly shaped small particles. In addition, radiation attenuating abilities of the tincal waste added with obsidians were determined by the calculation of tenth value layers, half value layers, mean free paths, mass attenuation coefficients, linear attenuation coefficients, fast neutron removal cross sections, effective atomic numbers and buildup factors using the newly produced Phy-X/PSD code. It is obtained that the samples show good radiation protection performances and the samples can be evaluated as better radiation shields for radiation applications especially in construction industry.

Kartal, V.; Emin Emiroglu, M.; Katipoglu, O.M.

H-weir is a combination of a rectangular gate and weir. Side weirs are applied to discharge flow and regulate the flow height. The present study presents the modeling of the H-side weirs using experiments and optimization based on SVM in a straight channel under free and subcritical flow conditions. The geometrical and flow parameters affecting the discharge capacity were determined based on dimensional analysis. The findings show that the weir flow is not in contact with the flow below the gate with increased vertical distance between the weir crest and gate top (d) and the upstream Froude number (F1). It was found that the discharge capacity of the H-side weir is 1.3–4.0 times higher than conventional side weirs and 1.6–9.0 times higher than side gates under the same conditions. Moreover, a discharge equation is derived from a/y1, h/b, b/B, F1 and d/a with an absolute percentage error of about 5.84%. The most successful model for predicting the discharge of the H-side weir was VMD-LSSVM. In addition, it was concluded that the established LSSVM, PSO-LSSVM and PSO-VMD-LSSVM models produced very satisfactory predictions.

Akoğuz, H.; Çelik, S.; Baris, O.

In recent years, biocementation has emerged as a promising technology for soil improvement research. This eco-friendly and sustainable approach involves a range of biochemical treatments, and its effectiveness is influenced by various factors. In this study, the effects of soil grain sizes, treatment duration (3, 6, and 11 days) and cementation solution flow rate (0.266, 0.400, and 0.666 ml/sec) on the engineering properties of treated soil were investigated by using the biocementation technique. The strength, calcite percentages, permeability, morphological appearance and structures of the treated sand soils were examined. According to the results, for each soil, different results were obtained with the same flow rates and treatment times. The highest strength value determined as 2406 kPa in the 11 day treatment at 0.400 ml/sec flow rate for smaller particle size of soil whereas the highest strength value obtained as 1504 kPa in the 11 day treatment at 0.266 ml/sec flow rate for larger particle size of soil. Higher strength results were obtained at lower flow rates (0.266 ml/sec) in samples with large grain diameter while strength results could not be obtained from it after treatment at higher flow rates (0.400, 0.666 ml/sec). In addition, strength results were obtained with a smaller grain diameter at a high flow rate (0.666 ml/sec), but decreased from 1599 to 1190 kPa when raising the treatment duration from 3 to 11 days. The flow rate and treatment duration in studies should therefore be chosen according to the particle size distribution of the soil.