Yazarlar
- Gul, Muhammet(16)
- Kahraman, Gökhan(13)
- Onat, Onur(13)
- Yucesan, Melih(12)
- Etli, Serkan(11)
- Mete, Suleyman(11)
- Akkurt, Nevzat(10)
- Karataş, Mehmet(10)
- Utku, Anıl(10)
- Yön, Burak(10)
- Akmaz, Düzgün(8)
- Cemalgil, Selim(8)
- Demir, Yakup(8)
- Ergen, Burhan(8)
- Çil, Zeynel Abidin(8)
- Akgül, Melek(7)
- Doğan, Gürkan(7)
- Gülmez, Nihan(7)
- Xu, Qian(7)
- Yildirim, Ozal(7)
- Yilmaz, Mehmet(7)
- Özceylan, Eren(7)
- Celik, Erkan(6)
- Göçmen, Elifcan(6)
- Orhan, Ahmet(6)
- Ertarğın, Merve(5)
- Serin, Faruk(5)
- Yilmazer, Merve(5)
- Zheng, Qiang(5)
- Akpolat, Mustafa(4)
- Atangana, A(4)
- Baskonus, HM(4)
- Bulut, H(4)
- Ding, Yulong(4)
- Dogan, Akar(4)
- Eristi, Huseyin(4)
- Hammouch, Z(4)
- Işık, Erdem(4)
- Karakose, Mehmet(4)
- Kaya, Sema Kayapinar(4)
Yayınlar
- MakaleAçık Erişim2026The New Dynamic of Global Competition: The Technological Utilization of Rare Earth Elements and Their Impact on International Relations
Durmuş, İrfan; Tam, Gürkan
Aim: This study aims to analyze the technological utilization, global reserve distribution, and production structures of rare earth elements (REEs), as well as the structural concentration and vulnerability of their supply chains, and to evaluate their implications for international relations, geopolitical power dynamics, and economic dependency. The study examines the strategic consequences of China’s dominance in global REE production and processing and develops policy recommendations regarding Türkiye’s potential integration into global value chains. Method: The research is designed as a secondary-data-based study employing a structured descriptive and comparative content analysis. Quantitative and qualitative datasets obtained from internationally recognized institutions, including the International Energy Agency (IEA), the U.S. Geological Survey (USGS), European Commission reports, and relevant national authorities, were systematically analyzed to assess reserve distribution, production concentration, and sectoral utilization patterns. Results: The findings demonstrate that REEs have evolved beyond their role as industrial raw materials and have become strategic instruments of global power projection. The high concentration of global production and processing capacity in China generates significant supply security risks and structural economic dependencies for advanced economies. While Türkiye’s declared reserve potential in Beylikova represents a substantial strategic opportunity, limitations in domestic processing capacity and high value-added manufacturing constitute major structural challenges. Conclusion: REEs have emerged as strategic commodities at the center of twenty-first-century geoeconomic competition, particularly in the contexts of energy transition, defense industries, and digital technologies. Ensuring sustainable supply security requires not only reserve diversification but also the development of refining capabilities, recycling technologies, and multilateral cooperation mechanisms. Türkiye’s ability to position itself as a reliable actor in global REE markets depends on the formulation of an integrated national strategy. Originality: This study contributes to the literature by approaching REEs through an interdisciplinary framework that integrates technological, geoeconomic, and international relations perspectives, thereby moving beyond purely geological or technical analyses.
- MakaleAçık Erişim2026İleri Teknoloji İhracatı ve Ar-Ge Harcamasının Büyüme Üzerindeki Etkisi: G20 Ülkelerinden Kanıtlar
Pehlivan, Ceren
Küreselleşme sonrası atılan yenilikçi adımlar teknolojik gelişimin sağlanmasına ve yayılmasına olanak sağlamıştır. Birçok büyüme teorisinde dışsal olarak yer alan teknoloji değişkeni içsel bir değişken haline gelmiştir. Teknolojik gelişmeler neticesinde ülkeler dış ticarette rekabet gücü sağlamıştır. Dış ticarette yaşanan gelişmeler ürün çeşitliliğin artmasına da yol açmıştır. Ayrıca ekonomik anlamda katma değer oluşmasıyla büyüme oranlarında da iyileşmeler yaşanmaya başlamıştır. Bu çalışmada G20 ekonomileri için bir analiz yürütülmüştür. Çalışmada 2000-2022 yılları baz alınmıştır. Yıllık veriler kullanılarak panel analizi yapılmıştır. İleri teknoloji ihracatı, Ar-Ge harcaması ile büyüme arasındaki ilişki hem teorik hem de ampirik olarak araştırılmıştır. Yapılan panel analizi sonucunda G20 ülkeleri genelinde ileri teknoloji ihracatı ve Ar-Ge harcamalarının büyüme üzerinde pozitif bir etkisi olduğu belirlenmiştir.
- MakaleAçık Erişim2026Osmanlı’da Nevzuhur Bir Endüstri: II. Abdülhamid Devrinde Gazoz Sektörü ve Üretimde Tağşiş Meselesi
Alp, Ruhat
II. Abdülhamid devrinde gazoz üretiminde endüstriyel bir aşamaya geçiş noktasında çok önemli adımların atılmasıyla, Osmanlı topraklarında modern gazoz sektörü doğmuştur. Öte yandan fabrikasyon üretimin yol açtığı muazzam rant, üreticileri zaten insanlığın kadim bir meselesi olan gıda tağşişine karşı daha istekli bir hale getirmiş; kimyasal katkı maddeleri gibi yapay gıda teknikleriyle, bugün bile hala güncel bir mesele olan gıda terörü küresel, çok boyutlu ve karmaşık bir hale gelmiştir. Söz konusu olgu, başta gazoz olmak üzere gazlı içecekler sektöründe dahi tüm boyutlarıyla hayatî bir mesele olarak ortaya çıkmıştır. Sorunun çözümü noktasında, Abdülhamid bürokrasisi tarafından dönemin teamüllerine de uygun bir şekilde, modern ve akılcı bir sağlık ve hijyen politikası ışığında, gerekli kurumsal, hukukî, teknik, maddî ve ilmî düzenlemeler yapılmaya çalışılmıştır. Bu durum Osmanlı Devleti’nin gazoz sektöründe modern kapitalist üretim sistemlerine uygun hareket etmesini ve üretici faaliyetlerinin kamu sağlığına uygun olup olmadığına dair bir teftişi zorunlu kılmıştır. Bu bağlamda bu makale, II. Abdülhamid devrinde gazoz sektörünün halihazırını, endüstrileşmeye yönelik girişimleri, üretimde gerçekleştirilen tağşiş faaliyetlerini ve devletin modern, faydacı ve yenilikçi bir sağlık konsepti üzerinden bu faaliyetleri engelleme çabalarını konu edinmektedir. Mezkûr dönemde bu temaya yönelik veriler, arşiv belgeleri ışığında ortaya konulmaya çalışılmıştır. İmtiyaz sözleşmelerinin de rehberliğinde kamu sağlığı merkezli endüstrileşme çabaları çalışmanın odak noktasını oluşturmaktadır.
- MakaleAçık Erişim2026Dijitalleşme ve toplumsal refah arasındaki ilişkinin pls-sem ile analizi
Geyik, Dilek Veysikarani
İlgili çalışmada, ülkelerin dijital kapasitelerini değerlendiren Ağ Hazırlığı Endeksi (Network Readiness Indekx – NRI) ile toplumsal refah ve gelişmişlik düzeyini ölçen Sosyal Gelişme Endeksi (Social Progress Indekx – SPI) arasındaki ilişkinin incelenmesi amaçlanmıştır. NRI, dijital altyapı, dijital beceriler ve dijital yönetişim boyutlarını kapsarken, SPI eğitim, sağlık, güvenlik, fırsat eşitliği ve temel insan ihtiyaçları gibi toplumsal göstergeleri içermektedir. Çalışmanın veri seti, 117 ülkenin 2024 yılına ait NRI ve SPI alt boyut verilerinden oluşturulmuş olup, dijitalleşmenin toplumsal refah üzerindeki etkilerini test etmek amacıyla Kısmi En Küçük Kareler Yapısal Eşitlik Modellemesi (PLS-SEM) yöntemi uygulanmıştır. Analiz sonuçlarında, dijitalleşmenin toplumsal refah üzerindeki etkisinin güçlü ve istatistiksel olarak anlamlı olduğunu belirlenmiş; dijital kapasitenin toplumsal ilerleme üzerinde belirleyici bir rol oynadığı gözlenmiştir. PLS-SEM kapsamında değerlendirilen ölçüm modelinin güvenilirlik ve geçerlik açısından uygun olduğu, Cronbach α, ρC, ρA ve AVE değerlerinin tüm yapılar için kabul edilebilir düzeylerde gerçekleştiği belirlenmiştir. Yapısal modele ilişkin açıklanan varyans (R²) değeri ise SPI için 0,807 olarak hesaplanmıştır. Bununla birlikte, Önem–Performans Matrisi Analizi (IPMA) bulguları, dijitalleşme göstergesinin alt boyutları arasında dijital beceri ve dijital altyapının SPI üzerindeki etki düzeyinin en yüksek olduğunu, dijital becerinin yüksek performans sergilerken dijital altyapının görece düşük performans gösterdiğini ortaya koymaktadır. Elde edilen bulgular, dijital kapasitenin stratejik biçimde geliştirilmesinin toplumsal ilerlemeyi destekleyen ve yönlendiren kritik bir unsur olduğunu göstermektedir.
- MakaleAçık Erişim2026Comparative Analysis of the Seismic Risk of Tunceli-Ovacık Rural Building Stock Using Different Rapid Screening Methods
Polat, Berivan Yılmazer; Ayhan, Ezgi
Located at the intersection of the Yedisu Segment, a seismic gap, and the active Ovacık Fault, the Tunceli-Ovacık district is a region with a high earthquake risk but an unclear level of structural fragility. This study aims to assess the seismic safety of the rural building stock located in a seismically critical area. To this end, the Turkish Rapid Visual Screening (RVS), based on local parameters, and the Canadian Seismic Survey Method, widely used in international literature, were applied to determine the current condition of the buildings; the earthquake risk of the region was analyzed based on the results obtained. Furthermore, similarities and differences between the methods were comparatively examined to ensure scientific integrity. Within the scope of the study, 209 buildings representing the building typology in the region, 88% of which are masonry-mixed systems, were analyzed using both rapid assessment algorithms. While the overall risk distribution ratios were similar, building-level matching analyses showed a medium level of agreement between the methods. This indicates that the local and universal methods, rather than definitively verifying each other, provide complementary data by focusing on different parameters in the seismic assessment of the rural building stock. This study demonstrates that an integrated risk mapping approach, where different methodologies complement each other, can offer a rapid and reliable decision support mechanism for urban transformation strategies in cities with high earthquake risk, such as Tunceli.
- MakaleAçık Erişim2026Analysis of buildings in Tunceli - Pülümür district with the Canadian seismic screening method
Gundogdu, Yunus Emre; Polat, Berivan Yilmazer
This study, which was conducted in the P & uuml;l & uuml;m & uuml;r district of Tunceli, was carried out in an area with high seismic risk due to the region's proximity to the Bing & ouml;l-Yedisu Fault. In the study, the earthquake safety of the existing building stock was assessed using visual inspection methods. In this context, 172 buildings in the P & uuml;l & uuml;m & uuml;r district of Tunceli province were examined in detail in terms of earthquake safety using the Canadian Seismic Screening Method. In the analysis, seismic safety levels of the buildings, structural and nonstructural risks were taken into consideration and seismic priority indexes (SPI) were determined. The results of the study revealed that a large portion of buildings in the P & uuml;l & uuml;m & uuml;r district carry different levels of risk of earthquake. Specifically, the evaluated building stock was entirely constructed before the critical year of 2007 and exhibits high seismic vulnerability. This critical threshold is technically attributed to two main regional factors: the design practices predating the 2007 Turkish Earthquake Code and the absence of ready-mixed concrete technology in Tunceli province prior to that year. Furthermore, based on the method's classification, it is suggested that buildings with a Seismic Priority Index (SPI) greater than 20, which indicates High to Very Hazardous risk levels, should be prioritized for detailed assessment and retrofitting, and that local governments should develop incentive policies for these mitigation efforts.
- MakaleAçık Erişim2026Scopus SJRQ1Upcycling Agricultural Biomass into Functional Bio-Oils through Pyrolysis: Toward Sustainable Rejuvenation of Asphalt Binder
Furtana Yalcin, Beyza; Yilmaz, Mehmet; Yalçin, Erkut; Vural Kok, Baha
This study investigates the feasibility of utilizing bio-oils derived from agricultural waste materials (such as straw, olive pomace, and pine cones) as rejuvenating additives in reclaimed asphalt pavement (RAP) containing bituminous mixtures, offering a sustainable and environmentally friendly approach in asphalt technology. The primary objective of the study is to enhance the physical and mechanical properties of aged binders using ecofriendly alternatives, thereby developing high-performance asphalt mixtures without harming the environment. The bio-oils, produced through pyrolysis, were evaluated in comparison with two commercial rejuvenators. Key performance criteria, including Marshall stability, moisture damage resistance (TSR), indirect tensile stiffness modulus (ITSM), and fatigue life, were tested. The results indicate that natural rejuvenators not only soften the aged binder but also effectively balance the flexibility, strength, and deformation resistance of the mixture. Notably, straw oil exhibited superior performance in terms of both high stability and extended fatigue life, while olive pomace oil demonstrated remarkable success in moisture resistance. Although commercial additives were effective to a certain extent, they failed to achieve the same level of structural compatibility and sustainability provided by natural bio-oils. In this regard, the study provides strong evidence that agricultural biomass waste can serve as a value-added solution in asphalt pavements, in alignment with the principles of the circular economy. In conclusion revealed that mixtures containing 75% RAP rejuvenated with straw oil achieved 11% higher Marshall stability and up to 14.5 times longer fatigue life compared to virgin mixtures, while olive pomace oil-based mixtures reached a TSR value of 81.5%, demonstrating superior moisture resistance.
- MakaleAçık Erişim2026Piezoelectric energy harvesters in bridge structures: Evaluation of optimal placement and energy harvesting
Sen, Bugra; Polat, Alper; Kapicioglu, Abdullah; Esen, Hikmet
In the present study, energy is harvested from vibrations in bridge structures caused by vehicle passages using piezoelectric energy harvesters (PEHs). In order to maximize the energy harvested, it was aimed to specify the optimal locations of PEHs. In the study, energy harvesting from vibrations in bridge structures was achieved using three different vehicle loads and three different piezoelectric materials. The project of the Ku & scedil;saray & imath;-2 bridge, located in Ku & scedil;saray & imath; village in Baskil, Elaz & imath;& gbreve;, was modelled in the ANSYS program using real measurements. The bridge was analyzed for modal, harmonic, and piezoelectric energy harvesting, respectively. The type with the highest energy production was determined using three different piezoelectric materials (PZT-4, PZT-5A, and PZT-8) for a total of 9 PEHs, and a total of 13 different analyses were performed under three different vehicle loads (60 kN, 90 kN, and 120 kN) to compare the results. The maximum total power obtained from all nine PEHs was 1.484 & micro;W under the 120 kN load with PZT-5A. The maximum power obtained from a single PEH (PEH-1) was 0.49 & micro;W. This power achieved will be adequate for wireless sensor systems used for monitoring the structural health of bridges, and considering that energy harvesting through vibration is independent of meteorological elements, unlike energy sources such as solar and wind, the environmental damage caused by waste batteries in existing systems will be prevented with the dissemination of these systems. With the development of these systems, the energy needs of services such as lighting and traffic signs can be supplied. The results provide an important foundation for the development of vibration-based energy harvesting systems in bridge structures. Thus, the study stands out as an innovative step toward sustainable energy generation in structural engineering.
- MakaleAçık Erişim2026Scopus SJRQ1Optimization, high-temperature resistance, and sulfate durability of basalt powder–blended alkali-activated slag mortars
Arslan, Furkan; Dener, Murat; Karataş, Mehmet; Benli, Ahmet
This study investigates the feasibility of using basalt powder (BP), an industrial by-product with limited reactivity, as a partial substitute for granulated blast furnace slag (GBFS) in alkali-activated systems. A comprehensive experimental program was conducted in two stages: first, a systematic optimization was performed by varying mixture parameters, including BP content, alkali dosage, activator modulus, and curing temperature to evaluate compressive strength development; second, selected binder compositions were used to produce self-compacting mortars, which were further examined for flexural strength, high-temperature resistance, and sulfate durability. The results demonstrated that moderate substitution levels (up to 20–30 % BP) could achieve satisfactory compressive strength, particularly under elevated curing temperature (60 °C) with 8 % Na2O and low to moderate modulus values. At 300 °C, mixtures with 20 % BP exhibited strength enhancement due to additional geopolymerization, demonstrating superior thermal stability compared to the control. Crucially, the incorporation of BP enhanced sulfate resistance, with the 40 % BP mixture exhibiting a slight increase in compressive strength after long-term exposure, in contrast to the marked deterioration of the GBFS-only system. Consequently, this study demonstrates that BP can be effectively utilized as a sustainable binder component, offering a practical solution for waste management while enhancing the durability of alkali-activated mortars against aggressive conditions.
AtıfScopus15WoS13OpenAlex10
İncele - MakaleYayıncıda açık erişim2026Scopus SJRQ1Experimental study of an alternative precast concrete beam–column connection with embedded steel block detail
Baltaci, Alihan; Sunca, Fezayil; Şahi̇n, Muhammed Cihat; Şen, Doğa; Keçeci̇, Bedirhan; Polat, Alper; Altunişik, Ahmet Can
Precast systems have gained increasing popularity due to their advantages in construction speed, cost efficiency, and quality control. However, past earthquakes have revealed that beam–column connections are often the most vulnerable regions in precast structures, making their seismic performance a critical area of investigation. This study investigates the cyclic behavior of two full-scale precast specimens with different beam–column connection configurations: a code-compliant, Moment-Resisting Emulative-Welded Connection detail (MRCON) and an alternative Embedded Steel Block Connection detail (ESBCON). Both specimens were tested under quasi-static reversed cyclic loading to evaluate their hysteretic response, energy dissipation, stiffness degradation, residual displacements, and modal characteristics. The results demonstrate that while MRCON provided higher initial stiffness and energy dissipation, it experienced severe localized damage and rapid structural deterioration at larger drift ratios. In contrast, the embedded steel block in ESBCON successfully distributed the damage across a wider joint region, leading to a more gradual stiffness reduction and slightly lower residual displacements. Although the overall structural efficiency of ESBCON was partially hindered by the slippage of the steel block, it achieved a competitive level of moment transfer capacity compared to the conventional welded connection detail, highlighting its potential as a damage-distributing alternative once slip-mitigating modifications (surface roughening to enhance bond and embedding within the column) are implemented.
- MakaleAçık Erişim2026Scopus SJRQ1Geospatial evaluation of river basin small hydropower potential using AHP
Korkmaz, Meral
This study develops an integrated Geographic Information Systems (GIS) and Analytic Hierarchy Process (AHP) framework to accurately identify small hydropower plants sites that support sustainable water–energy planning. The approach is applied to the Peri River Basin in Eastern Türkiye by combining multisource remote sensing datasets with a semi-automated narrow-valley detection technique to enhance the spatial precision of site selection. Nine hydrological and physiographic criteria including stream order, rainfall, slope, geology, drainage density, elevation, land use land cover, Stream Power Index SPI and Topographic Wetness Index TWI were weighted using the AHP method to generate a five-class suitability map for small hydropower plants development. A major contribution of this study is the explicit integration of valley morphology into the conventional GIS–AHP workflow, which significantly improves the identification of hydropower favorable river segments. Results indicate that approximately 3% of the basin exhibits very high suitability, while 46% is moderately suitable for run-of-river small hydropower plants development. Model validation was performed by overlaying the suitability map with the locations of existing dams/hydropower facilities, showing that current facilities are mainly located in high-suitability zones. Separately, the workflow identified 13 newly proposed high-suitability candidate dam sites (P1–P13), selected from screened suitable dam points using narrow-valley detection criteria. By minimizing ecological disturbance and aligning with watershed-based management principles, the proposed GIS-supported multicriteria method provides a transferable and cost-effective decision-support tool for small-hydropower planning in rural and mountainous basins, offering practical contributions to sustainable resource management and the water–energy nexus.
AtıfScopus2WoS2OpenAlex4İncele - MakaleAçık Erişim2026Scopus SJRQ2Sustainable self-compacting mortars: mechanical, durability and microstructural evaluation with cement replacement materials under aggressive environmental conditions
Karabulut, Büşra; Yön, Merve Şahin; Karataş, Mehmet
The aim of this study is to assess the mechanical, physical and durability properties of environmentally friendly self-compacting mortars produced using materials containing industrial waste and natural stone. The test series were produced by substituting diatomite (D) and C class fly ash (F) with Portland cement (PC) up to 30% by weight. To evaluate the workability, mechanical and durability properties of self-compacting mortars (SCM), a total of 19 series, one of which was a reference sample, were prepared. The samples, whose mechanical properties and durability properties were investigated under sulphate attack and freeze-thaw effects, were prepared as 40 × 40 × 160 mm, and the series, whose physical properties were examined, were prepared as 50 × 50 × 50 mm. Also, SEM/EDS (Scanning Electron Microscope - Energy Dispersive X-Ray) and XRD (X-Ray Diffraction) analyses were carried out to evaluate the microstructural properties of the mixtures. When the 90-day compressive strength results were examined, it was determined that the highest decrease in compressive strength compared to the control sample occurred in the D20F10 sample with a rate of 61%, and the least decrease occurred in the D5 series with a rate of 10%. When the losses in compressive strength were evaluated after 50 freeze-thaw cycles, it was determined that there was a 100% reduction in the binary and ternary series containing D15 and D20. After six months of sulphate exposure, the D5F25 sample exhibited the most significant compressive strength reduction at roughly 40%, whereas the D15F15 series experienced the least compressive strength decline at around 5%.
- MakaleYalnız künye2026Scopus SJRQ1From trash to technology: Ai-driven waste classification with hybrid CNN-transformer approach for sustainable recycling
Utku, Anil
The increasing amount of waste globally requires more efficient recycling processes and increases the importance of intelligent, automatic classification systems. Since traditional waste separation methods are time-consuming and have high error rates, artificial intelligence-based solutions have great potential in this area. In this study, the effectiveness of deep learning-based waste classification models was investigated, and nine different waste types were classified using DenseNet121, EfficientNetB0, ResNet50, ViT, DenseNet121-ViT, EfficientNetB0-ViT, ResNet50-ViT. Experimental results show that hybrid CNN-ViT models achieved the highest accuracy rates. Mainly, the EfficientNetB0-ViT model exhibited the best performance with a 95% accuracy rate and made a balanced classification for all waste types. The model can optimize recycling processes by ensuring the correct separation of wastes and contribute to environmental sustainability by reducing misclassification. Artificial intelligence-supported waste management systems offer an effective solution in critical areas such as reducing greenhouse gas emissions, saving energy, and supporting environmentally friendly urban planning. The findings of this study reveal that deep learning-based artificial intelligence models are an important tool for sustainable environmental management.
AtıfScopus1WoS1OpenAlex3İncele - MakaleAçık Erişim2026Scopus SJRQ1Multi-Task NILM with Anomaly Detection Using a Hybrid CNN–BilSTM–Transformer Model
Gunay, Mihriban; Demir, Yakup; Zhilevski, Marin
Non-Intrusive Load Monitoring (NILM) enables estimation of the energy use of individual appliances in smart buildings from a single aggregate meter. In practice, however, this task is not straightforward. Signals from different appliances can overlap, and the measured data may also include distortions such as spikes, drops, and noise. To address these issues, this study presents a multi-task triple-hybrid deep learning framework that handles appliance classification and anomaly detection together. The model brings together 1D-CNN, BiLSTM, and Transformer Attention so that local patterns, temporal dependencies, and wider contextual information can be learned within the same structure. It also uses a dual-output design to classify appliance categories and detect anomaly types simultaneously. Experiments were carried out on Building 1 of the UK-DALE dataset with four appliances: kettle, microwave, washer dryer, and fridge freezer. For the anomaly task, synthetic disturbances were added to segmented signal windows and grouped as normal, spike, drop, and noise. To check how well the proposed framework handled different scenarios, it was tested on both the UK-DALE and REDD datasets. Looking at the main UK-DALE results, the model correctly identified appliances 99.48% of the time and spotted anomalies with 98.80% accuracy. A secondary test on the REDD dataset yielded an 86.44% classification score. This proves the architecture can adjust to completely new power grid environments without losing its edge. On top of that, when pitted against standard benchmark models like Seq2Point, this triple-hybrid design clearly does a better job of mapping out complex signal changes. As a result, it yields much stronger anomaly detection metrics.
AtıfOpenAlex1İncele - MakaleAçık Erişim2026Scopus SJRQ1A Metric-Driven Evaluation Framework for Remaining Useful Life Prognosis with Quantified Uncertainty
Vashishtha, Govind; Chauhan, Sumika; Ertarğın, Merve
This paper introduces a novel metric-driven evaluation framework for Remaining Useful Life (RUL) prognosis in rotating machinery, featuring robust uncertainty quantification. Accurate RUL prediction is vital for optimizing maintenance and preventing failures, but existing methods often struggle with complex nonlinear degradation or lack reliable uncertainty estimates. Our proposed framework integrates a probabilistic Deep State Space Model (DSSM) with a variational inference approach to model complex, non-linear degradation trends and inherent aleatoric uncertainty. A key innovation is the use of the Slime Mold Algorithm (SMA) for efficient hyperparameter optimization, ensuring maximum accuracy. Furthermore, an online adaptation mechanism, governed by a heuristic reinforcement learning agent, allows the model to continuously update its knowledge and adapt to concept drift in real-time. Experimental validation on the IMS bearing dataset demonstrates superior RUL prediction accuracy, evidenced by the lowest Root Mean Square Error (RMSE) of 8.1829 cycles, and a PICP of 0.59416. This dual capability makes the framework highly suitable for real-world predictive maintenance, enhancing safety and reliability.
- MakaleAçık Erişim2026Scopus SJRQ1A smartphone-based vibration dataset for induction motor fault diagnosis under different speed and load conditions
Ertarğın, Merve; Orhan, Ahmet; Yıldırım, Özal; Chauhan, Sumika; Vashishtha, Govind
Induction motors are foundational components across industrial applications, valued for their inherent robustness, operational simplicity, and cost-efficiency. Maintaining their reliable function is paramount for a wide range of mechanical and electrical systems. However, they are prone to various mechanical and electrical faults, such as bearing defects, rotor issues, and voltage imbalances, which can significantly impair their performance and reliability. This study presents a novel vibration dataset for induction motor fault diagnosis, uniquely acquired using a smartphone-based inertial sensor rather than conventional industrial accelerometers. Vibration signals were recorded along three orthogonal axes (gx, gy, gz), alongside gravity-compensated acceleration components (guserx, gusery, guserz), enabling detailed analysis of both raw and gravity-free vibration characteristics. Data were collected under diverse conditions, including healthy operation and several fault types, across varying rotational speeds and load states. The dataset features long-duration vibration recordings sampled at 100 Hz, suitable for both time-domain analysis and window-based feature extraction. Its inclusion of multiple operating speeds and load conditions is ideal for studying the impact of operational variability on fault signatures. By leveraging low-cost and readily accessible smartphone sensors, this dataset supports practical and accessible vibration data acquisition for supporting the development, benchmarking, and validation of data-driven fault diagnosis methods. This resource is expected to significantly advance research in condition monitoring of induction motor, particularly for machine learning and signal processing applications using vibration data.
- MakaleYalnız künye2026Scopus SJRQ2Influence of infill design on mechanical behavior of PLA-TPU hybrid sandwich beams
Arikan, Volkan; Dogan, Akar; Guler, Serkan
The purpose of this work is to analyze the mechanical behavior of hybrid sandwich beams that were printed using the Fused Deposition Modelling (FDM) technology. These beams were made of Polylactic Acid (PLA) and Thermoplastic Polyurethane (TPU) materials. Standard mechanical tests (ASTM C393 and C365) were utilized in order to assess the impact that several infill patterns (Cubic, Octet, and Trihexagonal) and infill densities (ranging from 15% to 40%) had on the flexural and compression performance of the material. According to the findings, trihexagonal patterns demonstrated improved energy absorption capabilities when subjected to compression, but octet designs offered superior flexural stiffness, particularly in hybrid constructions. According to the findings of tests conducted with hybrid constructions consisting of a TPU core and a PLA surface layer, the effect of infill patterns on component strength is directly influenced by the change in the material character, and it is possible that various materials would exhibit different manifestations of this effect. These findings offer useful information that may be used to optimize lattice geometry and hybridization procedures for the purpose of developing high-performance lightweight structures for engineering applications.
AtıfWoS1OpenAlex2İncele - MakaleAçık Erişim2026Scopus SJRQ2Single-Ended Fault Detection and Fault Location in Transmission Lines Using Approximate Derivative
Akdağ, Mustafa; Mamiş, Mehmet Salih; Akmaz, Düzgün
Fault location in power transmission lines (PTLs) relies on impedance or traveling wave (TW) principles. TW approaches offer superior accuracy and high robustness against fault resistance. While multi-ended methods require precise terminal synchronization, single-ended TW (SETW) methods utilize measurements from one terminal, requiring accurate distinction of reflected waves. This study employs the computationally efficient approximate derivative (AD)—the difference between consecutive samples—for SETW fault detection and location. Normally near zero, the AD of modal signals produces sharp transitions during faults. Comparing AD output to a threshold achieves fault detection. The AD then identifies arrival times of the incident and reflected TWs. When using TW theory to distinguish reflections from the fault point and remote end, the fault distance is calculated from their arrival time difference. Validated through 293 diverse ATP simulated fault scenarios, the approach delivered highly accurate results despite using a lower sampling rate than established methods, utilizing an exceptionally short data window—only 2.03 ms for a 300 km line. Finally, operational boundaries for the signal-to-noise ratio (SNR) in noisy conditions are established.
- MakaleYalnız künye2026Scopus SJRQ2An Innovative Thermal Management Approach Enhanced by Thermoelectric Stations and Turbulators for Lithium-Ion Batteries
Tuğan, Volkan; Yardımcı, Uğurcan
The design of an effective battery thermal management system is critical to ensure the safe, efficient, and long-lasting operation of lithium-ion batteries. Excessive heat generation and temperature non-uniformity among cells in high energy density battery systems lead to performance degradation, accelerated aging, and an increased risk of thermal runaway. Although liquid-cooled systems and thermoelectric module-assisted solutions have been extensively investigated separately in the literature, studies that holistically evaluate multiple thermoelectric stations combined with an innovative flow channel design and turbulator integration remain limited. This gap constitutes a significant research need, particularly in terms of improving temperature uniformity and reducing maximum cell temperature. In this study, to address this research gap, a novel liquid-cooled battery thermal management system integrating thermoelectric coolers and turbulators within the flow channel is proposed. The thermal performance of the proposed system was systematically analyzed using computational fluid dynamics under three different configurations (conventional system, thermoelectric-assisted system, and turbulator-integrated thermoelectric-assisted system) and four different mass flow rates (0.0008, 0.0013, 0.0018, and 0.0023 kg/s). The results indicate that, at a mass flow rate of 0.0023 kg/s, the integration of thermoelectric coolers and turbulators reduces the maximum battery temperature by 8.95 K and the maximum temperature difference by 6.83 K. At the highest mass flow rate, the proposed system achieves a maximum battery temperature of 306 K and a maximum temperature difference of 4.5 K, ensuring both effective cooling performance and high temperature uniformity. Overall, the results in terms of cooling performance and temperature uniformity demonstrate that the combination of thermoelectric modules and turbulators offers significant potential for advanced battery thermal management system applications and offers an effective solution for high-energy-density systems.
- MakaleAçık Erişim2026Scopus SJRQ1Real-time photovoltaic voltage data-driven dynamic green s-box generation framework for smart grid security
Aydın, Yılmaz; Garipcan, Ali Murat; Özkaynak, Fatih
In this study, a dynamic substitution box (s-box) generation method is proposed using real-time voltage data obtained from photovoltaic (PV) panels as an environmentally sensitive entropy source. These data, affected by environmental conditions such as solar radiation and temperature, exhibit irregular and unpredictable temporal behavior, offering strong potential for cryptographic randomness generation. In this context, the 0–1 test, Kolmogorov Entropy (KE), scale-index analysis, and the National Institute of Standards and Technology (NIST) SP 800-22 test suite are applied to PV voltage data collected at 1-minute intervals, experimentally confirming their chaotic dynamics and high-entropy characteristics. Following appropriate preprocessing and nonlinear mathematical transformations, the validated data are utilized to generate 8-bit s-box structures. The cryptographic strength of the generated s-boxes is quantitatively evaluated using standard security metrics, including nonlinearity (NL), Differential Probability (DP), Linear Probability (LP), Strict Avalanche Criterion (SAC), and Bit Independence Criterion (BIC). The findings reveal that PV data can serve as a functional resource not only for energy monitoring but also for randomness-based cryptographic construction. This approach enables lightweight cryptographic solutions for resource-constrained edge devices requiring <1 KB of memory and supports context-aware data security in renewable energy infrastructures.
