Sürdürülebilir Kalkınma Amaçları

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Araştırmacılar(39)

• Akpinar, Salih
• Akyürek, Eda Feyza
• Ateş, Onur Kazım
• Azaklı, Zeki
• Beder, M.
• Beder, Murat
• Belet, Ali Kadir
• Boynueğri̇ Kaplan, Emine
• Budak, Selahattin
• Celen, Ali
• Çelik, Ayhan
• Çelik, İ.
• Ekmekci, Dursun
• Ersoy, Uğur
• Genc, Omer
• Hacisalihoglu, I.
• İlgar, Gamze
• Kaplan, Erdar
• Karabudak, Filiz
• Keleş, Abdulsamet
• Köse, Sami
• Kucuk, Haydar
• Kuvvet, Kemal
• Mazlum, Uʇur
• Sadık, Ali
• Sadik, Ayşegül Cansu
• Sahin, Birol
• Sarper, B.
• Sezer, İsmet
• Sivrioğlu, Selim
• Şahin, Yiğit Serkan
• Şenaslan, Fatih
• Şüküroğlu, Ebru Emine
• Taşdemir, Muharrem
• Terhan, Meryem
• Tezgel, Selim
• Ünker, Faruk
• Yıldız, Ali Suat
• Yurtkuran, Emre

• MakaleAçık Erişim2026/r/gumushane/19459
  Enhanced control of a two-wheeled gyroscopic combat robot with variable CMG disk speeds using LQR-Based neural network

  Oğuz, Yasin; Ünker, Faruk; Cetin, Gokhan

  This study proposes a hybrid control approach to improve the stability and adaptability of a two-wheeled gyroscopic combat robot by integrating deep learning with Linear Quadratic Regulator (LQR) control. Due to their inherently unstable nature, two-wheeled robots face challenges maintaining balance, especially when Control Moment Gyroscope (CMG) disk speeds vary, which significantly affect system dynamics. While LQR provides effective stabilization by minimizing a cost function, its performance degrades when disk speeds change. To overcome this limitation, a Neural Network (NN) was trained on 42001 precomputed LQR gain sets optimized for CMG disk speeds ranging from 800 to 5000 rad/s. The trained NN predicts appropriate coefficients in real time, enabling adaptive control under dynamic operating conditions. Simulation results demonstrate that the hybrid NN-LQR controller maintains stability under recoil forces up to 3000 N, where the conventional LQR loses balance about 4–6 seconds. Furthermore, the proposed controller reduces energy consumption by 21.6% during steady-state operation within the first 5 seconds and 10.6% under recoil conditions within the first 3 seconds compared to classical LQR. Although developed for a combat robot, the proposed framework offers a scalable solution for broader robotic applications such as search and rescue, surveillance, and autonomous navigation in complex environments, contributing to the advancement of intelligent control in robotics.

  İncele
• MakaleYalnız künye2026/r/gumushane/14196
  Effects of dual and single spark plug configurations on energy, exergy, and exhaust emissions in a spark ignition engine

  Altın, İsmail; Bayraktar, Hakan; Sezer, İsmet

  Effects of dual spark plug (DSP) operation in a spark ignition (SI) engine on energy, exergy, and exhaust emissions are numerically investigated in this study. A quasi–dimensional SI engine cycle model is used for the analyses. The practical correlations with no assume the fluid dynamics are occupied for the simulation of intake and exhaust periods and the turbulent flame propagation analogy is assigned for the modeling of combustion. The second law of thermodynamics is added to the cycle model to execute the exergy analysis. The thermodynamic parameters such as in–cylinder pressure and temperature, ignition delay, and burn duration with the engine performance parameters are evaluated in the energy analysis. The exergies transferred via heat, work, and exhaust gases, besides destroyed exergy, fuel chemical exergy, thermomechanical exergy and total exergy are compiled for the exergy analysis. The carbon monoxide (CO), nitrogen oxide (NO), and carbon dioxide (CO2) emissions are defined for emission performance analysis. The results show that DSP operation affects moderately energy, exergy, and exhaust emissions. The best results were obtained at dimensionless spark plug location (ratio of spark plug location radius to cylinder radius–Xsp) of 0.2 for DSP compared to centrally located single spark plug (SSP).

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  İncele
• MakaleAçık Erişim2026/r/gumushane/13855
  Regression-Based Controller Design Using LQR Data for a Two-Wheeled Gyroscopic Combat Robot

  Oğuz, Yasin; Çetin, Gökhan; Ünker, Faruk

  Two-wheeled gyroscopic robots are challenging to balance due to their intrinsic instability and sensitivity to external disturbances. This study proposes a hybrid control approach that combines a linear quadratic regulator (LQR) and a regression-based machine learning model to increase stability and adaptability. The regression model is trained with data collected from an LQR-controlled system to predict the optimal control responses under different conditions. The proposed approach utilizes state-space representation and the Jacobian linearization technique to design and simulate the robot’s performance under both controlled and random disturbance profiles. Simulation results indicate that the proposed method ensures steady motion even in dynamic, uncertain environments and increases resistance to external disturbances. Compared to the conventional LQR control method, the regression-enhanced model dynamically adjusts the control parameters, effectively reducing oscillations throughout the robot’s motion and achieving an average energy saving of approximately 80 %. These results demonstrate that robust, adaptive control in autonomous two-wheeled robotic systems can be achieved by fusing data-driven models with classical control techniques.

  İncele
• MakaleYalnız künye2026/r/gumushane/13798
  Electromechanical characterization and deep learning-based force prediction in 3D-printed PLA core–shell composites

  Ekmekci, Dursun; Kaplan, Emrah

  In this study, composite samples were produced using fused deposition modeling to contain an outer layer of red insulating polylactic acid and an inner core of black conductive polylactic acid. The mechanical properties of the samples were determined using three-point bending experiments, and their electro-mechanical impedance responses during loading were monitored using impedance experiments. To examine the effects of physical aging and crystallization, the composites were heat-treated at 50 °C for 2, 4, and 6 hours. The insulating polylactic acid exhibited brittle fracture with a sharp post-peak force drop, whereas the conductive polylactic acid showed a ductile fracture mode accompanied by substantial energy dissipation. The physically aged composites were stiffer and less ductile, which was attributed to the presence of partially crystallized and partially relaxed molecules, especially around the glass transition region. In support of the observed properties, scanning electron microscopy images confirmed that the fractured layers were smoother compared to the ductile conductive layers, which had surface roughness patterns resembling fibrillated or lamellar structures. Additionally, the impedance signals obtained during the bending experiments were linked with the corresponding mechanical properties using an advanced deep learning model that could model the electric signals to accurately provide the corresponding real-time force values.

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• MakaleYalnız künye2026/r/gumushane/13782
  Investigation of the adhesion properties of duplex coating on AZ91 alloy surface by MAO/HiPIMS-PVD methods

  Kaplan, Emine Boynueğri; Şüküroğlu, Süleyman; Şüküroğlu, Ebru Emine

  This study focuses on enhancing the surface properties and minimizing the mechanical incompatibility between the AZ91 magnesium alloy and the coating by applying CrAlYN/CrYN gradient coatings through the HiPIMS-PVD method, combined with the enlargement of a MgO intermediate layer via the Micro Arc Oxidation (MAO) method. The duplex coating approach was designed to strengthen adhesion and structural integrity between the substrate and the coating. Coating parameters for both MAO and HiPIMS-PVD processes were optimized using a Taguchi L4 orthogonal array, and the coatings were analyzed using SEM, EDS, XRD and scratch testing. MAO coatings exhibited porous and rough surfaces with volcanic morphologies. The best adhesion performance under MAO conditions was achieved with 650 V, 700 Hz, and a Type B solution, resulting in a critical load value of Lc₂ = 24 N. CrAlYN/CrYN gradient coatings alone showed coating thicknesses from 0.83 μm to 1.66 μm with compact and homogeneous microstructures. Adhesive strength was relatively low (Lc₂ = 5–10 N). In the duplex coating configuration, CrAlYN/CrYN coatings were deposited on the MAO-formed MgO layer, significantly increasing adhesion. Critical load values (Lc₂) ranged from 90 to 110 N, with the highest adhesion achieved under low CrY target voltage and current conditions. The findings demonstrate that the MAO/HiPIMS-PVD duplex coating method substantially improves adhesion and surface characteristics of AZ91 alloy, offering a promising solution for advanced surface engineering applications.

  İncele
• Derleme MakaleYalnız künye2026/r/gumushane/13432
  A review study of recent advancements in polymer heat exchanger technology in the aspect of heat transfer

  Celen, Ali; Budak, Selahattin; Celen, Pınar; Dalkılıç, Ahmet Selim

  Many applications use metallic heat exchangers, but some operating conditions, such as desalination, exhibit wear and corrosion problems. Thus, it is important to develop and use alternative materials to metals for such conditions. Although polymers have low thermal conductivity, corrosion resistance, cost-effectiveness, and lightweight, polymer heat exchangers can be constructed to overcome this problem. They were introduced in the last decades; advancements in 3D printing technology help manufacture complex, novel, and thin heat transfer surfaces. Although review studies are limited, recent research has not explored heat transfer-based reviews of heat exchangers produced by additive manufacturing and polymer hollow fibre methods. In this study, polymer heat exchanger works were reviewed and classified according to tube diameter as polymer and polymeric hollow fibre heat exchangers as the most updated ones. Generally, the studies focused on the thermal performance of heat exchangers constructed with metal and polymer materials, and the results were compared to determine the usability of polymer-based ones. As a result, polymeric hollow fibre heat exchangers may compete with metallic ones due to low wall resistance and enhanced heat transfer surface area because of the development of manufacturing technology. Also, the cost and weight of polymeric hollow fibre exchangers are lower, and they can be operated under corrosive conditions. Finally, it is obvious that increased research is needed to enhance the properties of polymer materials to increase the performance of this type of heat exchanger.

  İncele
• MakaleAçık Erişim2026/r/gumushane/12264
  Dynamic and Mechanical Properties of Nanoparticle Doped Aramid/Glass Fiber Reinforced Interply Hybrid Composites

  Sadik, Ayşegül Cansu; Karabudak, Filiz; Kula, Muhammed Emin

  In this study, the mechanical and dynamic properties of glass/aramid interply hybrid composites reinforced with four different nanoparticles were investigated. Firstly, matrix modification was performed and composite plates were manufactured by hand lay-up technique. Silicon dioxide (SiO2), graphene (GNP), silver (Ag) and cerium oxide (CeO2) nanoparticles were added to the epoxy matrix as reinforcement. With the addition of nanoparticles, the highest tensile (16%) and flexural (67.3%) strengths were observed in Ag reinforced composites. Tensile (16.8%) and flexural (14.4%) strengths decreased with the addition of graphene nanoparticles. Tensile and flexural tests revealed delamination, matrix and fibre rupture in all plate types. As a result of modal analysis, the highest natural frequency values and the lowest damping ratios were determined in the FFBC boundary condition. The addition of nanoparticles improved the mechanical properties of the composites in general.

  İncele
• MakaleAçık Erişim2026/r/gumushane/12155
  Carbon footprint assessment and reduction strategies of a university campus in Turkey

  Türle, İbrahim; Celen, Pınar

  As key institutions and significant energy consumers, universities have a critical responsibility to lead efforts in energy efficiency and renewable energy use to reduce their environmental impact. In this regard, the Gümüşhane University carbon probe has produced the first study that makes it possible to identify the sources of greenhouse gas emissions and provides the opportunity to track, measure, and suggest reduction strategies in the years to come. The carbon footprint of Gümüşhane University from 2017 to 2023 has been calculated and examined in this paper. The IPCC and DEFRA conversion factors served as the foundation for the computations. The results showed that the university's use of natural gas and electricity was responsible for almost all of its carbon emissions. According to the IPCC and DEFRA, the 2017 emissions were 4999.93 and 4667 tCO2e, respectively. Following a move to online instruction in 2020, emissions decreased to 3894 tCO2e under DEFRA and 4365.44 tCO2e under IPCC. However, as campus life resumed its pre-pandemic pace in 2022 and 2023, emissions rose again, surpassing 5252.04 tonnes of CO₂e by 2023 using the IPCC method and 4042 tonnes of CO₂e using the DEFRA method. These results suggest that universities need to focus on their energy consumption patterns in order to reduce their carbon emissions, for example by placing greater emphasis on renewable energy sources, energy efficiency, and balanced consumption. The outcomes of this research will act as a guideline not only for Gümüşhane University to help it reach its sustainability goals, but also for other university administrations when formulating effective carbon reduction strategies, and for institutions seeking to measure or benchmark their environmental performance.

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• MakaleAçık Erişim2026/r/gumushane/12135
  Comparative Mechanical and Thermal Performance of Graphene- and Silver Nanoparticle-Reinforced PLA Fabricated by FDM 3D Printing

  Karabudak, Filiz

  The increasing demand for high-performance and multifunctional polymer materials has driven interest in improving the mechanical properties of polymer components produced through additive manufacturing. This study aims to systematically investigate and comparatively evaluate the effects of low-content nanofiller incorporation on the structural, thermal, and mechanical performance of PLA-based materials produced via fused deposition modeling (FDM), with a focus on identifying filler-dependent behavior under different loading conditions. In this study, polylactic acid (PLA) composites reinforced with 0.5 wt.% graphene (Gr) and 0.5 wt.% silver (Ag) nanoparticles, added separately, were produced using fused deposition modeling (FDM) and comparatively investigated. Each nanofiller was incorporated individually into PLA-based filaments, and standard test specimens were fabricated via 3D printing. Structural, thermal, and mechanical properties were evaluated using tensile, compressive, and three-point bending tests, along with SEM, EDS, XRD, FTIR, DSC, and TGA analyses. The results showed that pure PLA exhibited typical brittle behavior and a single-stage thermal degradation profile. The tensile strength of pure PLA was 41.93 MPa, and the flexural strength was 70.76 MPa. The addition of 0.5 wt.% graphene led to noticeable improvements, particularly in flexural properties, while only a minimal (almost negligible) increase was observed in tensile strength, with tensile strength increasing to 42.24 MPa (+0.74%) and flexural strength increasing to 110.78 MPa (+56.6%). In contrast, 0.5 wt.% Ag exhibited mixed and load-dependent mechanical behavior, with slight improvements in flexural strength but reductions in tensile and compressive properties, where tensile strength decreased to 22.13 MPa (−47.2%) while flexural strength increased to 112.06 MPa (+58.3%). Structural and thermal analyses indicated that both nanofillers did not significantly alter the PLA matrix chemically, while contributing to controlled changes in material properties primarily through physical interactions. The novelty of this work lies in the comparative evaluation of graphene and silver nanoparticle reinforcement at a fixed low loading level within FDM-processed PLA, combined with a comprehensive and correlated analysis of mechanical, structural, and thermal behavior on the same specimen sets, enabling a clearer understanding of filler-dependent performance mechanisms in additively manufactured nanocomposites. Overall, it was concluded that low-rate nanofiller additions, when properly dispersed, may lead to selective improvements in the performance of PLA-based composites depending on filler type and loading mode, and show potential for advanced engineering applications such as lightweight structural components, functional sensors, and additive-manufactured parts requiring tailored mechanical performance and multifunctionality.

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• MakaleAçık Erişim2026/r/gumushane/12123
  Experimental and Modeling Study of Fluidity in Ductile Iron (GGG40)

  Coşar, Mehmet; Şüküroğlu, Ebru Emine; Güngör, Kadir; Çolak, Murat

  Ductile irons (spheroidal graphite cast irons, SGI) are widely used in automotive and energy systems due to their high strength, ductility, and excellent machinability. The casting quality of these alloys largely depends on the flow and filling behavior of the molten metal, namely its fluidity. In this study, the effects of pouring temperature, filling time, and metallurgical quality on the fluidity of GGG40 ductile iron were investigated through both experimental and numerical approaches. Experimental trials were conducted at pouring temperatures of 1350 °C, 1400 °C, and 1450 °C; metallurgical quality levels of 10%, 50%, and 90%; and filling times of 5 s and 10 s. The fluidity lengths were measured and statistically evaluated. The results revealed that increasing the pouring temperature and metallurgical quality significantly improved fluidity, while shorter filling times allowed the molten metal to travel longer distances before solidification. Modeling studies performed using a commercial casting simulation software showed strong correlation with the experimental data. Microstructural examinations indicated that higher pouring temperatures and improved metallurgical quality led to a more homogeneous distribution of graphite nodules and an increased ferrite fraction in the matrix. The findings provide valuable insights into the influence of process parameters on the fluidity behavior of ductile iron and offer critical design data for enhancing casting quality and productivity in industrial foundry applications.

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