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SIFT: Sifting file types-application of explainable artificial intelligence in cyber forensics
No full textArtificial Intelligence (AI) is being applied to improve the efficiency of software systems used in various domains, especially in the health and forensic sciences. Explainable AI (XAI) is one of the fields of AI that interprets and explains the methods used in AI. One of the techniques used in XAI to provide such interpretations is by computing the relevance of the input features to the output of an AI model. File fragment classification is one of the vital issues of file carving in Cyber Forensics (CF) and becomes challenging when the filesystem metadata is missing. Other major challenges it faces are: proliferation of file formats, file embeddings, automation, We leverage and utilize interpretations provided by XAI to optimize the classification of file fragments and propose a novel sifting approach, named SIFT (Sifting File Types). SIFT employs TF-IDF to assign weight to a byte (feature), which is used to select features from a file fragment. Threshold-based LIME and SHAP (the two XAI techniques) feature relevance values are computed for the selected features to optimize file fragment classification. To improve multinomial classification, a Multilayer Perceptron model is developed and optimized with five hidden layers, each layer with ixn\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}\end{document} neurons, where i = the layer number and n = the total number of classes in the dataset. When tested with 47,482 samples of 20 file types (classes), SIFT achieves a detection rate of 82.1% and outperforms the other state-of-the-art techniques by at least 10%. To the best of our knowledge, this is the first effort of applying XAI in CF for optimizing file fragment classification
Characterizing the effects of liner and fiber-reinforced resin composite shell on fracture energy in type-III high-pressure composite tanks
No full textThe increasing adoption of fuel-cell vehicles, driven by their environmentally friendly zero-emission features, is a crucial step towards reducing environmental damage. However, current research primarily focuses on stress-related aspects of pressurized tanks, leaving a critical knowledge gap regarding potential fractures within the tank's body, which can accelerate pressure tank failure. This study aims to address this concern by analyzing alternative fiber materials beyond carbon fiber in a finite element analysis model, with the primary objective of enhancing the durability of pressurized tanks for hydrogen-fueled vehicles against fracture loading. The investigation revolves around the fracture behavior of type-III high-pressure composite tanks, pivotal components for the secure operation of hydrogen-powered fuel cell vehicles. Various configurations of Al6061 and Al7178 liners coupled with six distinct fiber materials and six different winding orientations [(+/- 15/90)n]T, (+/- 30/90)n, [(+/- 45/90)n]T, [(+/- 55/90)n]T, [(+/- 60/90)n]T, and [(+/- 75/90)n]T have been meticulously assessed to provide an in-depth analysis of fracture energy behavior in composite tanks. The stress intensity factor (GI) was computed using a compact tension model developed in Abaqus, for all composite variations under consistent conditions, providing a robust foundation for understanding the fracture behavior. Additionally, MATLAB was utilized to calculate the effective elastic modulus for the selected composite materials. Subsequently, the strain energy release rate was derived from the relationship between the GI and the effective elastic modulus of composite tanks. The derived GI revealed notable improvements in fracture resistance for specific composite shells and liner materials, particularly at higher winding orientations. The results emphasized the superior performance of boron-epoxy composite shells for type-III pressure vessels, exhibiting the lowest GI values and exceptional crack resistance. Notably, Al7178 combined with boron-epoxy outperformed Al6061 composites at higher winding orientations, while glass-epoxy shells exhibited greater susceptibility to crack propagation, especially in specific ply orientations.Scientific Research Coordination Unit of Adana Alparslan Turkes Science and Technology University [23103004]This work was supported by Scientific Research Coordination Unit of Adana Alparslan Turkes Science and Technology University with project number of 23103004
Contribution of silane modification of halloysite nanotube to its poly (butylene terephthalate)-based nanocomposites: structural, mechanical and thermal properties
No full textPolybutylene terephthalate (PBT) nanocomposites were melt-blended with two types of Turkish halloysite nanotubes (HN). Naturally occurring HN samples were used to produce PBT-based composites at the HN compositions of 1%, 3%, 5%, and 10%. Findings of neat and silane-coated HN-containing composite samples were compared to investigate the interfacial adhesion between polymer matrix and reinforcement material. According to test results, a 1% amount of HN was found to be the most suitable option in the case of mechanical and thermal properties of composites. Additionally, silane-modified grade displayed highly indicative improvements compared to pristine HN clay due to better interfacial adhesion of halloysite nanotubes to the PBT matrix was accomplished. Property enhancements achieved for composite samples containing low contents of HN were confirmed by morphological examinations. As a result, the PBT/ 1% HN-S composite sample was bookmarked as the most suitable option to fabricate HN-reinforced PBT-based nanocomposites in terms of mechanical, thermo-mechanical, morphological, thermal, and physical performances based on the findings in this study. Silane-modified halloysite grades exhibited better results, and they were found to be more suitable in the case of applications of PBT.Adana Alparslan Turkes Science and Technology UniversityNo Statement Availabl
Enhancement of the response speed of CIGS-based photodetector by Te-doping
No full textCu(In,Ga)Se2 (CIGS) based devices are promising candidates for high performance photodetector applications. The present work investigated the effects of Te-doping on the properties of CIGS layers and studied the performance of photodetectors (PDs) fabricated on these films. The films were vacuum evaporated on glass substrates and their morphological, structural and optical properties were evaluated after an annealing step at 550 degrees C. Morphological data indicated that undoped CIGS films had non-uniform surface features with large grains separated by nanoparticles. Addition of 6.6 % Te improved the morphology and yielded a smoother layer. Further increase in Te concentration showed appreciable reduction in surface feature size and shape. X-ray diffraction patterns showed that increasing the Te amount in CIGS caused a shift in the XRD peaks towards smaller angles pointing to replacement of Se atoms by Te. Peak splitting at higher Te samples suggested a graded structure with Se and Te amounts changing through the thickness of the film. Raman analysis demonstrated formation of CuInGa(Se,Te)2 (CIGST) compound. According to Tauc's approximation, CIGS films with and without Te atoms possessed two energy band gaps of Eg1 and Eg2 that were in the ranges of 1.10-1.28 eV and 1.16-1.36 eV, respectively. Electrical data obtained from photodetector devices showed a responsivity of 4.44x10- 1 A/W and a detectivity of 8.01x107 Jones for Te-free material, while the rise/fall times were measured as 34/148 ms. A much faster response speed of 19/20 ms was reached for devices fabricated on films with 10.2 % Te. This work demonstrated, for the first time, the fabrication low-cost and high-performance metalsemiconductor-metal (MSM) type CIGST-based PDs
Multidisciplinary optimization of high aspect ratio composite wings with geometrical nonlinearity and aeroelastic tailoring
No full textThis study presents a systematic numerical approach for the design and optimization of high aspect ratio composite wings subjected to aerodynamic loads. The primary objective is to develop a multi-objective, multidisciplinary optimization framework that considers aerostructural constraints, such as subsonic aeroelasticity and geometrical nonlinearity. The incorporation of anisotropic properties of composite materials is emphasized to construct lightweight aerospace structures. Aeroelastic tailoring, a technique leveraging these properties, is employed in the optimization process. The proposed methodology integrates three analysis tools, Finite Element software for structural behavior simulation, an in-house Reduced Order Model (ROM) framework for nonlinear aeroelastic analyses with tailoring capabilities, and Particle Swarm Optimization (PSO) as a population-based stochastic optimization method. This integration enables the development of a powerful numerical approach, implemented in the Nonlinear Aeroelastic Simulation Software (NAS2) package, for designing composite wings with optimized aeroelastic and structural performance. The proposed methodology has broad applicability in aerospace engineering, encompassing aircraft and unmanned aerial vehicles, offering significant potential to enhance their design and overall performance.Scientific and Technological Research Council of Turkey (TUBITAK) [220N396]This study has been supported by the Scientific and Technological Research Council of Turkey (TUBITAK Project No. 220N396 and TUBITAK 2219 program). The authors gratefully acknowledge the support of this study
Improvement of energy harvesting capability in grid-connected photovoltaic micro-inverters
No full textIn this paper, a multi-stage micro-inverter system depending on a dual neutral point clamped (D-NPC) inverter is developed for low power photovoltaic (PV) applications. The primary objectives of this study are determined as improving the performance of the proposed D-NPC inverter-based micro-inverter and its controller to ensure better system reliability and promote the overall efficiency. In comparison with conventional systems, the designed system provides many advantages: (1) utilization of lower rating switching components, (2) reduced switching frequency and voltage stress, (3) reduced the size of filter components, (4) higher efficiency, and (5) lower total harmonic distortion (THD). The weighted efficiency of the system is remarkably increased by the value of 2.15% compared to the conventional micro-inverter and reached 93.73%. Furthermore, the THD value of the output current is measured below 3% for the proposed system with the small size of passive filtering elements. Further, dynamic grid support and anti-islanding detection capabilities are provided through the utilized controller structure to fulfill grid codes. Consequently, obtained results demonstrate that the improved system can be a considerable candidate for photovoltaic micro-inverter applications in terms of weighted efficiency, output current THD, and reasonable cost.Scientific Research Project Unit of Cukurova University [FDK-2017-9136]; Turkiye Bilimsel ve Teknolojik Arastirma Kurumu [EEEAG-118E940]This work was supported by the Scientific Research Project Unit of Cukurova University [FDK-2017-9136]; Turkiye Bilimsel ve Teknolojik Arastirma Kurumu [EEEAG-118E940]
A Life Cycle Analysis of a Polyester-Wool Blended Fabric and Associated Carbon Emissions in the Textile Industry
No full textThe effect of industrialization and technological developments and the rate of population growth have begun to disrupt the ecological balance in the world. A large share of the deterioration of this balance is due to the rapidly increasing energy demands of people. Fossil fuels and renewable energy sources are used to obtain the energy that is needed by human beings. Most of the world ' s energy needs are met by fossil fuels such as coal, oil, and natural gas. These resources, which we call fossil fuels, cause many parallel environmental problems, such as global warming, climate change, and carbon emissions, for the world and nature. The most affected by all these experiences, of course, is the entire production sector, which is dependent on energy. However, textile and apparel, which is a pioneer in taking steps towards harmonization with the Green Agreement, is one of the sectors that started the transition to green energy within the scope of the European Union and brands ' net-zero targets. Within the scope of the Green Agreement, Turkey has participated and started to work for a 70% carbon reduction, which is the target for 2030, and carbon neutrality, which is the target for 2050. Therefore, within the scope of these targets, the textile sector of cukurova Region, which has the highest export rate in Turkey, was chosen. Within the scope of this study, carbon emission, which is one of the global problems, was examined within the framework of the ISO 14067-ISO Product Based Carbon Footprint (CF) standard by examining the production of a textile company, and the results were analyzed in detail. The main innovation of this article is to follow all stages of the fabric called Tricia, which is the most produced product in the textile industry, from its entry as fiber to its exit as fabric in the factory, and to calculate and analyze the amount of carbon that is released into nature. The dynamic and experimental results showed that it was determined that 6.00 tons of carbon dioxide carbon were released in the time it took for the fabric to go to the sewing room as a fabric.Scientific Project Unit of Adana Alparslan Turke, Science and Technology University [23103006]This research was supported by the Scientific Project Unit of Adana Alparslan Turke, Science and Technology University (Project Number: 23103006)
China’s Diplomacy and Intensifying Geopolitical Tensions in Neighboring Nations
No full textChina is seen as both a land of opportunities and a significant threat with its rapidly growing economy and increasingly rising political profile in the global arena. China’s military expenditures and population are important indicators that cannot be ignored in terms of international politics in the global power struggle towards 2050. In parallel with its economic performance, its pro-active attitude in Africa and South America outside the Asia-Pacific geography has made China a key country not only on a regional scale but also in global politics. China, which isolated itself throughout the Cold War period, began to grow economically with the foreign opening policy implemented in 1978 under the leadership of Deng Xiaoping. One aspect of China’s rise is the impact of these economic connections on China’s political relations with its neighbors. Peaceful relations have increased, especially due to its extensive economic ties with its Western and Asian neighbors. Therefore, the increase in economic interdependence between China and its neighbors is associated with the improvement of political relations. This study examines China’s diplomacy and geopolitical tensions, economic fluctuations, military and political processes and commercial relations intensifying in neighboring countries, and is expected to make significant contributions to science and researchers. © 2025 selection and editorial matter, Shilpa Deo and Fatma Feyza Gündüz; individual chapters, the contributors
Reflections on the vernacular mosques in the Souf region, Algeria: An attempt to inventory the local architectural language
No full textThe architectural design of mosques has evolved and been interpreted within various Islamic countries, influenced by diverse local contexts and specific circumstances. This article investigates the vernacular mosques in the Souf region, located in the southeast of Algeria. The study aims to reveal the local architectural language used in these mosques in order to develop an inventory of vernacular mosques. The investigation employs a hybrid approach, combining historical research methods, morphological analysis, and typology. The tools and techniques of data collection were based mainly on architectural surveys, in-situ observations, and non-directive interviews with the local inhabitants (testimonies). The findings confirmed that although the architecture of the vernacular mosques of the Souf respects the archetype of the Arab mosque and expresses a vernacular style particular to the region. However, their three-dimensional morphology presents a specific silhouette that is not found elsewhere in Algeria. These mosques are distinguished by their staircase minaret and raised dome (on a double tambour), which often dominates the mosques by their height and monumentality
E-araç fı losunun belı rlenmesı ı çı n entegre bı r sı mülasyon-optı mı zasyon modeli ve çok krı terlı karar verme modelı
No full text25.01.2025 tarihine kadar kullanımı yazar tarafından kısıtlanmıştır.Lisansüstü Eğitim Enstitüsü, Endüstri Mühendisliği Ana Bilim DalıTeknoloji ve dijitalleşme büyük bir hızla gelişmektedir. Günümüzde birçok ürüne çok hızlı erişim sağlanabilmektedir. Ürün satın almak için mobil uygulama kullanımının artması, sipariş sayısında artışa yol açacak, bu da siparişlerin firmadan müşteriye ulaştırılmasını içeren taşıma sisteminde yoğunluğu arttıracaktır. Son mil taşımacılığındaki bu yoğunluk, fosil yakıtların yanmasından kaynaklanan zararlı gazların salınımını da artıracaktır. Firmaların çevreye verdikleri zararı azaltabilmeleri için alternatif yeşil araçları ulaşım sistemlerine entegre etmeleri gerekmektedir. Bu çalışmada, simülasyon-optimizasyon modeli kullanılarak şirketlerin elektrikli araçlara geçişi sırasında CO2 emisyonu ve teslimat maliyeti minimizasyonu hedeflerini karşılayacak araç filoları belirlenmiştir. Çalışma kapsamında üç farklı drone kapasitesi, e-motosiklet ve klasik motor incelenmiş ve beş farklı araç modu için 7 farklı senaryo geliştirilmiştir. Yatırım maliyetlerini de dikkate alarak en uygun senaryonun belirlenmesinde TOPSIS yaklaşımı kullanılmıştır. Orta kapasitedeki drone ve e-motorsiklet kullanımı en yüksek önceliğe sahip senaryo olarak belirlenmiştir.The advancement of technology and digitalization is progressing rapidly. Nowadays, many products can be readily accessed with great speed. The use of mobile applications has increased, leading to a rise in the number of orders, which in turn will increase the density of vehicles used in the last phase of the transportation system that involves the delivery of orders from the company to the customer. This intensity in last-mile will also increase the emission of harmful gases from the combustion of fossil fuels. Companies need to integrate alternative green vehicles into their transportation systems in order to reduce environmental damage without falling behind in the competition. In this study, the vehicle fleets that will meet the companies' CO2 emission and delivery cost minimization targets as they transition to electric vehicles were identified using the simulation-optimization model. The study focused on analyzing three different drone capacities, as well as e-motorcycles and classic motorcycle. Additionally, seven scenarios were developed to evaluate five various vehicle modes. TOPSIS approach was used to determine the most suitable scenario, taking into account CO2 emission, delivery cost and investment costs. The use of medium-capacity drones and e-motorcycles has been determined as the highest priority scenario