Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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Now showing 1 - 10 of 807
  • Article
    Decision-Support Approaches for Sustainable Water Resource Management in Northwest Algeria
    (Polish Society of Ecological Engineering – PTIE, 2025) Meskine, Ahmed; Cherif, El Amine; Zerouali, Bilel; Ouadja, Abid; Santos, Celso Augusto Guimaraes; Bailek, Nadjem; Baba, Alper
    This study investigates water resource management in the Wilaya of Mostaganem, northwest Algeria, using the water evaluation and planning (WEAP) decision support tool in combination with the analytic hierarchy process (AHP). As water scarcity becomes increasingly critical due to population growth, agricultural demands, and climate variability, effective management strategies are essential. This research employs WEAP to simulate various water demand and supply scenarios, assessing the impacts of irrigation efficiency, industrial development, and climate conditions on water availability. Under the ASI scenario, unsatisfied water demand may reach 4.3 hm3 per year by 2027. However, improving irrigation efficiency could reduce this by up to 50% compared to the reference scenario. Seasonal variations reveal deficits reaching 3.2 hm3 per month during the summer months of July through October. Additionally, the study highlights that a significant increase in water demand, exceeding 80 hm3 by 2060, can be mitigated through improved water supply initiatives, such as constructing new dams. The integration of AHP enables the prioritization of management strategies based on stakeholder preferences, demonstrating that adapting to climate change can stabilize demand below 50 million cubic meters. This integrated approach provides valuable insights for policymakers and stakeholders in developing sustainable water resource strategies that address the challenges faced by the Mostaganem region.
  • Article
    Investigation of the Effect of the Cutting Parameters on Cutting Forces and Tool Wear in the Stack Drilling of a Carbon Fibre-Reinforced Thermoplastic Matrix Composite and Aa7075
    (Univ Zagreb Fac Mechanical Engineering & Naval Architecture, 2025) Coskun, Ali; Etyemez, Ayhan; Ay, Mustafa; Kurt, Mustafa; Katmer, Sukran; Seker, Ulvi; Nohuz, Mine
    This study investigate the stack drillability of unidirectional (UD) carbon fibre reinforced thermoplastic matrix PAEK/CF composite and AA7075 plate utilised in aerospace. The effects of the cutting parameters on cutting forces during the drilling process of thermoplastic matrix composites and aluminium materials were experimentally analysed. Drilling operations were carried out on a CNC Vertical Machining Centre under dry-cutting conditions. For three different drill types, three different cutting speeds, and feed rate combinations, a total of 810 holes were drilled in a full factorial experimental design with 30 replicates for each combination. The damage on the hole surfaces on the drilled composite was identified with an optical microscope. The numerical data were obtained in the composite testing laboratory and analysed using Minitab (R) 21.1 statistical software and transformed into graphs. The most suitable drill type and cutting parameters were determined for the drillability of composite with thermoplastic matrix and aluminium (AA7075) plates when stacked.
  • Article
    Comparative Analysis of Ahp and Swara Methods for Prioritizing Conservation Projects Supported by Heritage Funds: a Case Study From Turkey
    (Inst Advanced Science Extension, 2025) Avsar, Oncu Basoglan; Ekinci, Kerem; Soker, Ali Ikram
    Effective budget allocation and financial management are vital for preserving cultural heritage, particularly in countries with limited resources. This study focuses on Turkey's Contribution to the Conservation of Built Heritage (CCBH) fund, which supports heritage preservation through government funding. Despite the fund's importance, a structured method for prioritizing project applications is lacking. This research proposes a decision-making framework for assessing and ranking conservation funding requests using Multiple-Criteria Decision-Making (MCDM) methods. The study applies and compares the Analytic Hierarchy Process (AHP) and the Step-Wise Weight Assessment Ratio Analysis (SWARA) to assign weights to assessment criteria. The findings demonstrate that SWARA provides a more efficient and practical approach to prioritizing conservation projects. The proposed framework aims to assist decision-makers and conservation practitioners in optimizing the allocation of funds to safeguard cultural heritage effectively. (c) 2025 The Authors. Published by IASE. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
  • Article
    Homogeneity Enhancement of Oxide Additives in Boron Carbide by Precipitation Method
    (University of Novi Sad, Faculty of Technology, 2025) Toksoy, M.F.; Elçi, C.
    This study elucidates the use of the precipitation method to enhance the uniformity of oxide additives in boron carbide ceramics. Achieving a homogeneous distribution of additives is critical, as higher additive content tends to degrade the mechanical properties of boron carbide. In this research, yttrium and aluminium hydroxide salts were dispersed and incorporated into boron carbide slurry under highly alkaline conditions. The mixture was aged and subsequently calcined to produce metal oxide layers around the boron carbide particles. The additive-to-boron carbide ratio and calcination conditions were systematically varied and the resulting powders were characterized using SEM, EDX and zeta potential analyses. The precipitation method effectively improved additive dispersion, achieving a uniform distribution. Furthermore, samples processed through precipitation exhibited higher densities compared to conventional benchmark samples. © 2025 University of Novi Sad, Faculty of Technology. All rights reserved.
  • Article
    Regression Analysis of Material Properties and Hardness of Dense Boron Carbide
    (Wiley, 2025) Toksoy, M. Fatih; Haber, Richard A.
    Material properties directly affect the final performance of the produced articles. This study aims to establish a correlation between materials properties and hardness of boron carbide samples. Ten different boron carbide powders were sintered to high densities by spark plasma sintering, and material properties (grain size, density, stoichiometry, and free carbon) were analyzed. Hardness tests were conducted on these samples. All experimental procedures were completed by a single operator, and the same instruments were used for all the samples. Multiple linear regressions using the ordinary least squares method in SPSS were carried out to identify the relationship between hardness and material properties. Analyses showed density is the most dominant property, surpassing any other parameter. Grain size became more dominant at higher densities (>99%) and affected hardness results. Both grain size and density are the result of the starting powder and the densification procedure. This study showed that 80% of the hardness variation can be explained by this model.
  • Article
    Citation - WoS: 3
    Citation - Scopus: 3
    Hybrid Silica Aerogels From Bridged Silicon Alkoxides: Ultralow Thermal Conductivity for Low-Temperature Applications
    (Springer, 2025) Abebe, A. M.; Biesuz, M.; Vakifahmetoglu, C.; Cassetta, M.; Soraru, G. D.
    Hybrid silica aerogels are promising materials for thermal insulation applications. Highly porous aerogels were synthesized from bridged bis(triethoxysilyl)methane BTEM and triethoxysilane TREOS silicon alkoxides via the sol-gel process. The carbon content in the hybrid aerogels decreased with increasing amounts of TREOS. Crack-free monolith aerogels were synthesized through supercritical drying, which is crucial for thermal and optical investigations. The aerogels are characterized by high BET surface areas ranging from 700 to 1400 m(2)/g, pore volumes between 2.0 and 10.5 cm(3)/g, and a maximum porosity of 95%. The thermal conductivity of the aerogels at room temperature was measured via a hot disk apparatus. The materials exhibited ultralow thermal conductivity, reaching a minimum value of 15 mW/mK. This value ranks among the lowest reported values for silica-based aerogels in the literature. Optical transmittance measurements indicated high transparency, exceeding 80% in the visible region. Therefore, these exceptional properties of low density, high optical transparency, and low thermal conductivity make these materials promising candidates for transparent insulation applications.
  • Article
    Nitrate Sensing With Molecular Cage Ionophores: a Potentiometric Approach
    (Royal Soc Chemistry, 2025) Onder, Ahmet; Begar, Ferit; Kibris, Erman; Buyukcakir, Onur; Yildiz, Umit Hakan
    Nitrate ions are widespread environmental pollutants in water and soil, posing critical risks to both human health and ecosystems. This study introduces a molecular cage as a novel ionophore for potentiometric nitrate-selective ion-selective electrodes (ISEs) designed for enhanced specificity and sensitivity. Among six synthetic candidates, the electrode incorporating a 1,3,5-tri(p-hydroxyphenyl)benzene-based chlorotriazine pillared cage molecule (CAGE-1) exhibited superior performance, characterized by a linear response in the nitrate concentration range of 1.0 x 10-5 to 1.0 x 10-1 M, with a high coefficient of determination (R2 = 0.9971) and a slope of -53.1 +/- 1.4 mV dec-1. The electrode also achieved a limit of detection of 7.5 x 10-6 M. These findings highlight the potential of molecular cages as ionophores for nitrate sensing in environmental applications.
  • Article
    Experimental Study of Evolution of Breach Resulting From Piping at Upper Part of Earth-Fill Dam
    (Turkish Chamber Civil Engineers, 2025) Guney, Mehmet Sukru; Tayfur, Gokmen; Bor, Asli; Okan, Merve; Dumlu, Emre; Aklık, Pelin
    Piping and overtopping are the most important causes of earth-fill dam failure. Such dams may erode under seepage, causing a reduction in the structural strength. The aim of this study was to investigate the temporal evolution of the breach and flow rate from the breach resulting from the piping in earth-fill dams. The experiments were carried out at Hydraulics Laboratory of Civil Engineering Department of İzmir University of Economics. The dam was constructed by using a mixture consisting of 85 % sand and 15 % fine (low plasticity clay). In the first scenario a circular tunnel with a diameter of 2 cm was created along the centreline at 6 cm below the dam crest whereas in the second one it was located at the upper edge. Six cameras at different locations recorded the evolution of the progress of the breach formation. The pump flow rate was measured by magnetic flow meter, and the continuity equation was used to calculate the flow rate values from the breach. The time-varied values of the total breach areas were determined using the Gauss Area formula. The image processing method was also applied in the determination of the breach areas. The time-dependent changes of water depth in the channel were also recorded. The obtained experimental findings are presented and commented, together with the universal dimensionless curves. The failure of the dams occurred mainly because of the head cut erosion developed from downstream to upstream. When breaching started, the orifice flow was converted to open channel flow where breach bottom behaved like a broad crested weir. In the second scenario, the rigid lateral side considerably influenced the flow rate and the development of the breach. The peak flow rate corresponding to the first scenario was found approximately 2.3 times greater than that of the second one. The maximum values of all the breach parameters were reached earlier in the case of the seepage along the centerline. The ratios between the values corresponding to the first and the second scenarios were found as 3.25 and 1.75 for maximum breach areas at downstream and at upstream sides, respectively. These ratios were 2.44 and 1.37 for the average breach widths at downstream and upstream sides, respectively. A very good agreement was found between the area values obtained from Gauss area method and image processing technique, in both scenarios. This fact demonstrated that either of these two approaches can be used to determine the time-dependent breach areas. These experimental findings provide the opportunities for the calibration and validation of the numerical models used in the relevant numerical investigations. This study also offers guidance for the strategies concerning emergency action plans related to the failure of homogeneous earth-fill dams when the piping starts at upper part of the homogeneous earth-fill dams.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Numerical and Experimental Investigation of Aspect Ratio Effect on Aerodynamic Performance of Naca 4415 Airfoil Section at Low Reynolds Number
    (Assoc Mechanical Engineers Technicians Slovenia, 2025) Uemuetlue, Hatice Cansu Ayaz; Kiral, Zeki; Karadeniz, Ziya Haktan
    In this study, the effect of aspect ratio on the aerodynamic coefficients is investigated for a NACA 4415 airfoil profile. Four different aspect ratios which are 3, 5, 7, and 9 are evaluated with the computational fluid dynamics (CFD) simulations and the experiments. The CFD studies are performed using a threedimensional (3D) computational domain and by using the k-omega shear stress transport (SST) turbulence model for turbulence calculations. The measurements of the aerodynamic forces are carried out in open jet type wind tunnel using a three-component balance. CFD and experimental studies are performed at angles of attack from 0 degrees to 25 degrees and Reynolds number 85<middle dot>103. The results show that as the aspect ratio increases, separation points move towards the leading edge of the airfoil and the stall angle reduces. Furthermore, it is observed that the lift coefficients increase with the increasing aspect ratio. The results obtained indicate that there is a harmony between the experimental data and the CFD solutions.
  • Article
    Citation - Scopus: 1
    Investigating Early-Stage Mineralization Behavior and Bioactivity of Acid-Free Bioactive Glass 45s5 With Enhanced Dissolution Kinetics
    (Springer, 2025) Tuncer, Melisa; Yucesoy, Deniz T.; Karakus, Ceyda Oksel
    Nanostructured bioactive glass (BG) was synthesized through an acid-free sol-gel route (bioglass-AF) and the conventional acid-catalyst sol-gel process (bioglass-AC). The aim here is to eliminate the risk of residual acidic components in the BG while enhancing its functionality through nano-scale propduction. Scanning electron microscopy revealed the presence of highly porous structures and dense agglomerates composed of particles with a mean diameter of 45 nm in both samples. Bioglass-AC and bioglass-AF had specific surface areas of 1.48 m(2)/g and 2.73 m(2)/g, respectively, with an average pore size of similar to 5 nm. Faster mineralization kinetics were evident in bioglass-AF, compared to bioglass-AC, in Hepes-buffered salt solution. Following 14 days of immersion in artificial saliva, bioglass-AC and bioglass-AF lost 16% and 20% of their initial weight, respectively, confirming their bioactivity. None of the synthesized BGs stimulated cell growth up to 24 h but longer exposure to moderate concentrations (1.25 and 2.5 mg/mL) of bioglass-AF significantly enhanced cell viability, reaching 170% at 48 h. Overall, the comparative in vitro investigations proved that nano-structured 45S5 bioglass powders with improved mineralization and dissolution kinetics can be produced with an acid-free route, eliminating the risk of residual acidic components in the final product.