http://repository.enu.kz/handle/enu/19743 Fri, 03 Apr 2026 21:57:37 GMT 2026-04-03T21:57:37Z http://repository.enu.kz/handle/enu/30233 Voxel Interpolation of Geotechnical Properties and Soil Classification Based on Empirical Bayesian Kriging and Best-Fit Convergence Function Utepov, Yelbek; Aldungarova, Aliya; Mukhamejanova, Assel; Awwad, Talal; Karaulov, Sabit; Makasheva, Indira To support bearing capacity estimates, this study develops and tests a geoprocessing workflow for predicting soil properties using Empirical Bayesian Kriging 3D and a classification function. The model covers a 183 m × 185 m × 24 m site in Astana (Kazakhstan), based on 16 boreholes (15–24 m deep) and 77 samples. Eight geotechnical properties were mapped in 3D voxel models (812,520 voxels at 1 m × 1 m × 1 m resolution): cohesion (c), friction angle (φ), deformation modulus (E), plasticity index (PI), liquidity index (LI), porosity (e), particle size (PS), and particle size distribution (PSD). Stratification patterns were revealed with ~35% variability. Maximum φ (34.9◦ ), E (36.6 MPa), and PS (1.29 mm) occurred at 8–16 m; c (33.1 kPa) and PSD peaked below 16 m, while PI and e were elevated in the upper and lower strata. Strong correlations emerged in pairs φ-E-PS (0.91) and PI-e (0.95). Classification identified 10 soil types, including one absent in borehole data, indicating the workflow’s capacity to detect hidden lithologies. Predicted fractions of loams (51.99%), sandy loams (22.24%), and sands (25.77%) matched borehole data (52%, 26%, 22%). Adjacency analysis of 2,394,873 voxel pairs showed homogeneous zones in gravel–sandy soils (28%) and stiff loams (21.75%). The workflow accounts for lateral and vertical heterogeneity, reduces subjectivity, and is recommended for digital subsurface 3D mapping and construction design optimization. Wed, 01 Jan 2025 00:00:00 GMT http://repository.enu.kz/handle/enu/30233 2025-01-01T00:00:00Z http://repository.enu.kz/handle/enu/30232 Utilizing biofilm-enhanced coconut coir for microplastic removal in wastewater Zharkenov, Yerkebulan; Mkilima, Timoth; Abduova, Aisulu; Zhaksylykova, Lailya; Turashev, Agzhaik; Imambayeva, Raikhan; Imambaev, Nurlan; Jaxymbetova, Makpal; Smagulova, Aizada; Beysenbaeva, Elmira The pervasive presence and detrimental impact of microplastics in the environment pose a multifaceted and urgent challenge requiring innovative solutions and comprehensive mitigation strategies. This study investigated the efficacy of biofilm-enhanced coconut coir in removing microplastics from wastewater, addressing the pressing issue of microplastic pollution. Through comprehensive experimentation, the adsorption capabilities of coconut coir across various types and sizes of microplastics under different operational conditions were exam ined. The addition of biofilm significantly enhanced the adsorption capacity of coconut coir, leading to improved microplastic removal efficiencies, with typical specific surface area values increasing from 1000 m2 /g to 1200 m2 /g and pore volume from 0.5 cm3 /g to 0.6 cm3 /g with biofilm augmentation. Moreover, the study revealed consistent improvements in microplastic removal efficiency across different types and sizes of microplastics with biofilm presence, ranging from 85 % to 95 %, compared to removal efficiencies varying from 72 % to 82 % without biofilm enhancement. Langmuir analysis revealed that coconut coir exhibited favorable adsorption of microplastics, with and without biofilm, demonstrating high correlations between observed and predicted values (R2 = 0.999). These findings underscore the potential of biofilm-enhanced coconut coir as a promising solution for mitigating microplastic pollution in aquatic environments. Mon, 01 Jan 2024 00:00:00 GMT http://repository.enu.kz/handle/enu/30232 2024-01-01T00:00:00Z http://repository.enu.kz/handle/enu/30231 Utilization of banana peel-derived activated carbon for the removal of heavy metals from industrial wastewater Mkilima, Timoth; Zharkenov, Yerkebulan; Abduova, Aisulu; Sarypbekova, Nursulu; Kudaibergenov, Nurlan; Sakanov, Kuandyk; Zhukenova, Gyulnara; Omarov, Zhumabek; Sultanbekova, Parida; Kenzhaliyeva, Gulmira Metal plating industries generate wastewater containing heavy metals, necessitating effective treatment methods to mitigate environmental contamination. This study investigated the potential of banana peel-derived activated carbon (BPAC) and commercial activated carbon for heavy metal removal, addressing a pressing environmental concern. The analysis encompassed diverse pH levels, crucial for real-world applicability, offering valuable in sights into adsorption capacities and kinetics. The results revealed competitive performance of both materials, with typical lead (Pb) removal ranging from 4 to 6 mg/g and cadmium (Cd) from 3 to 5 mg/g. Commercial activated carbon exhibited slightly superior adsorption kinetics and capacities, highlighting its efficacy in heavy metal removal. Throughout the study, optimizing dosage proved essential for maximizing removal efficiency, emphasizing the practical implications of this research. Furthermore, the time-dependent behavior of adsorption kinetics underscored the importance of extended contact times for enhanced removal. Generally, BPAC emerged as a promising solution for heavy metal removal from industrial wastewater. It consistently achieved removal efficiencies typically ranging from 75 % to more than 90 %, making it a viable alternative in the realm of wastewater treatment. At pH 4, BPAC demonstrated significantly higher adsorption capacity, with lead (Pb) at 5.50 ± 0.20 (mg/g) and cadmium (Cd) at 4.10 ± 0.15 (mg/g), compared to slightly lower values for commercial activated carbon, Pb at 5.20 ± 0.25 (mg/g) and Cd at 3.90 ± 0.20 (mg/g). This study contributes significantly to wastewater treatment methodologies, offering sustainable and efficient approaches to address heavy metal contamination in industrial effluents. Mon, 01 Jan 2024 00:00:00 GMT http://repository.enu.kz/handle/enu/30231 2024-01-01T00:00:00Z http://repository.enu.kz/handle/enu/30230 Using modified Chebyshev functions for approximation in 5G technologies Yerzhan, Assel; Nakisbekova, Balausa; Manbetova, Zhanat; Boykachev, Pavel; Imankul, Manat; Dzhanuzakova, Raushan; Shedreyeva, Indira; Karnakova, Gaini This research addresses the critical challenge of broadband matching in radio engineering, focusing on enhancing phase-frequency response (PFC) linearity across wide frequency bands. A novel approach, utilizing modified Chebyshev functions, demonstrates significant potential in reducing phase distortions within 5G technology applications. Unlike traditional Chebyshev functions, this method incorporates strategically placed transmission zeros— complex conjugate pairs on the s-variable complex plane—without increasing the filter circuit's order. This innovation results in a low-order filter circuit characterized by uniform phase response and group delay characteristics (GDT), offering an effective solution for matching circuit design with less phase-frequency distortion and improved group delay uniformity across diverse load conditions. The modified Chebyshev approximation outperforms its classical counterpart in both phase linearity and selectivity within the 1 to 1.2 cutoff frequency range. This enhancement is crucial for the development of low-frequency filters, with broader implications for creating high-frequency, band-pass, and band-stop filters via known frequency transformations. Empirical results validate the proposed method's reliability and effectiveness, marking a significant advancement in the field of radio engineering by addressing broadband matching challenges with increased efficiency and simplified design implementations. Mon, 01 Jan 2024 00:00:00 GMT http://repository.enu.kz/handle/enu/30230 2024-01-01T00:00:00Z