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Application of artificial intelligence and soft computing methods for anomaly detection of intrusion attacks in cyber-physical and industrial systems
No full textSiber-fiziksel sistemler ve endüstriyel kontrol sistemlerinin dijitalleşmesi, bu sistemlere yönelik siber tehditlerin karmaşıklığını ve tehlikelerini artırmıştır. Özellikle davetsiz misafir saldırıları, sistemlerin sürekliliği ve güvenliği üzerinde ciddi bir tehdit oluşturmaktadır. Bu tez çalışmasında, siber-fiziksel sistemler ve endüstriyel kontrol sistemlerinde davetsiz misafir saldırılarının anomali tespiti için yapay zeka ve yumuşak hesaplama temelli yöntemlerin performansı sistematik bir şekilde incelenmiştir. Bu amaçla, CIC-ToN-IoT, CSE-CIC-IDS2018 ve Edge-IIoTset gibi güncel ve kapsamlı veri setleri kullanılarak çeşitli makine öğrenmesi, derin öğrenme ve yumuşak hesaplama teknikleri uygulanmıştır. Karar ağaçları, destek vektör makineleri, K-en yakın komşu, lojistik regresyon ve doğrusal diskriminant analizi gibi klasik makine öğrenmesi algoritmaları ile Evrişimli Sinirsel Ağ ve Uzun Kısa Dönemli Bellek gibi derin öğrenme yaklaşımlarının performansı değerlendirilmiştir. Ayrıca, bulanık mantık, Genetik Algoritmalar, Uyarlamalı Nöro-Bulanık Çıkarım Sistemi ve Derin Q Ağı gibi yumuşak hesaplama yöntemleriyle hem bağımsız hem de hibrit modeller geliştirilerek sistem performansı analiz edilmiştir. Elde edilen bulgular, klasik makine öğrenmesi modellerinin genellikle yüksek isabetlilik sunduğunu, ancak derin öğrenme ve yumuşak hesaplama temelli yöntemlerin, özellikle azınlık sınıflarında ve karmaşık veri setlerinde esneklik ve uyarlanabilirlik avantajları sağladığını ortaya koymaktadır. Çalışma, bu yöntemlerin siber-fiziksel ve endüstriyel kontrol sistemlerindeki uygulanabilirliğini göstermeyi ve bu alanda yapılacak ileri düzey araştırmalara katkı sunmayı hedeflemektedir.The digitisation of cyber-physical systems and industrial control systems has amplified the complexity and severity of cyber threats t
Evaluation of Physical Activity, Dietary Habits, and Income as Determinants of Health in European Continental Countries: A Data Envelopment Analysis Approach
No full textPurpose: The study aimed to evaluate the effectiveness of physical activity, dietary habits, and income indicators in European Continental countries using the data envelopment analysis method. Material and Methods: The study analysed data from 29 of 32 European continental countries. Input variables included physical activity, walking, dietary habits, and gross national income per capita, while output variables included depressive symptoms and obesity. Spearman analysis was performed to determine the correlation between these variables. Mahalanobis distance values were calculated to identify outlier countries. Finally, Data Envelopment Analysis was performed using the R Studio package. Results: According to the Charnes Cooper Rhodes (CCR) model, the average efficiency of the countries was found to be 0.90, while it was 0.91 according to the Banker Charnes Cooper (BCC) model. Based on the efficiency scores, seven countries were identified as efficient in the CCR model, and nine in the BCC model. Among the efficient countries, Serbia and Romania had the highest efficiency scores of 1.37 in the super-efficiency analysis. Discussion: The study results indicate that if six countries increased their input variables, they could achieve higher outputs, whereas 14 countries might achieve lower outputs if they were to increase their inputs
Comparison of myocardial perfusion scintigraphy and strain echocardiography in patients undergoing coronary angiography
No full textOBJECTIVE: Myocardial perfusion scintigraphy is a common non-invasive method for assessing ischemic burden, though artifacts can affect accuracy. Speckle-tracking strain echocardiography improves left ventricular function assessment, and global longitudinal strain correlates well with coronary artery disease. The aim of this study was to compare myocardial perfusion scintigraphy with global longitudinal strain in stable angina pectoris patients. METHODS: A total of 133 suspected coronary artery disease patients who underwent myocardial perfusion scintigraphy and coronary angiography were prospectively enrolled and classified as myocardial perfusion scintigraphy true positives or false positives based on coronary angiography results. Global longitudinal strain values for the epicardium, endocardium, and myocardium (avg) were calculated. RESULTS: Ischemic percentages of myocardial perfusion scintigraphy>12% and mid-wall global longitudinal strain<-18.4% correlated with true positive coronary angiography results. Left ventricular ejection fraction/global longitudinal strain mid ratio positively correlated with coronary artery disease presence and severity. Higher ischemic percentages of myocardial perfusion scintigraphy showed a negative correlation (r: -0.2606, p: 0.002) with global longitudinal strain, indicating a greater likelihood of coronary artery disease (OR 0.25, 95%CI 0.08-0.73, p: 0.012). Female sex was linked to fewer true positive myocardial perfusion scintigraphy results. CONCLUSION: The GLS value of the Left Ventricle obtained by two-dimentional strain echocardiography offers sensitivity and specificity similar to myocardial perfusion scintigraphy in the detection of coronary artery disease.. An elevated left ventricular ejection fraction/global longitudinal strain ratio is a significant predictor of the presence and severity of coronary artery disease
Bending analysis of functionally graded triply periodic minimal surface sandwich plates
No full textThis study investigates the bending behaviour of sandwich plates with functionally graded triply periodic minimal surface (FG-TPMS) cores under uniform loading and various boundary conditions. By employing a two-phase fitting technique, the effective properties of FG-TPMS cores are derived for three-unit cell models (primitive, gyroid, and IWP). The equilibrium equations are formulated using the virtual displacement principle and solved via the state-space method for plates with two simply supported edges. Results show that the proposed model achieves 12-15% lower deflection compared to conventional homogeneous cores, with gyroid structures exhibiting the highest stiffness (e.g. an elastic modulus 10% higher than that of the primitive structure). Comparative analysis with high-order shear deformation theory (HSDT) and refined plate theory (RPT) benchmarks shows <5% deviation, validating the accuracy of our approach. Additionally, an analysis of symmetric and asymmetric density distributions (Patterns A/B) reveals that Pattern B reduces deflection by 8-20% for slenderness ratios (a/h) of 5-20. This work advances theoretical studies on TPMS-based sandwich structures and provides a robust framework for optimizing their mechanical performance
The Cognitive Flexibility Scale for Individuals With Autism Spectrum Disorder: A Turkish Adaptation and Validation Study
No full textPurposeThe primary aim of this study was to adapt the Cognitive Flexibility Scale (CFS) for individuals with Autism Spectrum Disorder (ASD) into Turkish and to examine its psychometric properties, specifically its structural validity and internal consistency.MethodsThe study initially involved a sample of 303 parents of students diagnosed with ASD. After data screening for outliers, the final analyses were conducted on a sample of 298 participants. Confirmatory Factor Analysis (CFA) was employed to evaluate the factor structure of the Turkish version of the CFS. Internal consistency was assessed to determine the scale's reliability.ResultsThe initial CFA, which tested the original scale's factor structure, demonstrated a poor model fit and unacceptable reliability. Several items had factor loadings below the 0.30 threshold. Following the removal of one subscale based on item loadings and model fit indices, a subsequent analysis of a revised 4-factor, 22-item structure yielded satisfactory fit indices and high internal consistency.ConclusionThe findings suggest that the adapted 4-factor, 22-item Turkish version of the CFS demonstrates satisfactory structural validity and high internal consistency, making it a valid and reliable instrument for assessing cognitive flexibility (CF) in individuals with ASD as reported by their parents in a Turkish context
The Role of Associative Learning in Ant Learning and Memory
No full textLearning, the enduring change of behavior of an animal with experience, has been one of the most scrutinised cognitive ability of animals ranging from simple forms to the most advanced ones. Learning is considered in two categories as non-associative and associative. Simple forms of responses including habituation and sensitization are considered as non-associative while associative learning can be either via classical conditioning or instrumental conditioning. Studies on insects, particularly those on honey bees, dipterans and ants as model organisms presented a good deal of evidence for learning and memory to differing extents. Ants are known to rely on various sensory modalities ranging from olfactory to visual, tactile and magnetoreceptive in order to accomplish vital tasks not only in but also outside their nests. Studies with ants revealed empirical evidence for reliance of learning and memory in different tasks in nature and artificial laboratory conditions. In the present study, we tried to bring together the data on the role of associative learning in behavioral responses of ants in different contexts. The neural control of associative learning and the ecology of ant learning as an adaptive tool were discussed.Scientific and Technological Research Council of Trkiye (TUBIdot;TAK) [2211/A]; Scientific and Technological Research Council of Turkiye (TUBITAK)Ozguer Mert was financially supported by the Scientific and Technological Research Council of Turkiye (TUBITAK) with the grant PhD 2211/A
The Effect of Balance Coordination Program on Postural Stability in Children with Dyslexia: An Observational Clinical Study
No full textBackground The aim of study was to determine changes in the balance parameters after balance-coordination program in children with dyslexia. Methods Prospectively sixteen children with dyslexia were included. Balance parameters of dyslexic children were compared with healthy children. Dyslexic children were given balance coordination exercises three times a week for six weeks. The static and dynamic balance were tested with the Modified Clinical Test of Sensory Interaction on Balance (mCTSIB) and Limits of Stability (LOS) tests and Pediatric Quality of Life Inventory Scale (PedsQL) was used to assess quality of life. Results Postural sway velocities on the firm and foam surfaces with eyes opened and closed conditions of mCTSIB were found to be decreased and movement velocity, endpoint excursion, and maximum excursion in anterior and posterior directions of LOS, social, school and total scores of PedsQL increased in the dyslexia group after the treatment (p < 0,01). Conclusion The children with dyslexia have distinct alterations on balance compared to their peers. These alterations, along with their quality of life, have shown to be greatly improved after a exercise program
A targeted nanotherapeutic approach against CD44 prostate cancer stem cells
No full text[Abtsract Not Available
The European Union's energy problem: Unavoidable dependence
No full textAvrupa Birliği (AB), dünyanın en önemli siyasi ve iktisadi yapılarından biri olarak enerji ihtiyacını karşılama konusunda büyük oranda dış kaynaklara bağımlı bir yapı içerisindedir. Bu bağımlılık, özellikle Rusya ile olan ilişkileri çerçevesinde hem mali hem de jeopolitik ve güvenlik bağlamlarında kırılganlıklar oluşturmaktadır. Bu çalışma, AB'nin enerji bağımlılığını azaltmaya yönelik politika girişimlerini, bu süreçteki gerek yapısal gerekse siyasi sorunları ve Rusya'nın enerjiyi bir dış politika aracı olarak kullanmasının AB stratejilerine etkilerini incelemektedir. Çalışma, enerji ilişkilerini yalnızca arz-talep dengesiyle incelememiş; bağımlılık, karşılıklı bağımlılık ve asimetrik bağımlılık kuramları bağlamında AB-Rusya enerji dinamiklerini çok boyutlu bir bakış açısıyla analiz etmektedir. 2000'li yıllardan itibaren AB, yenilenebilir enerji yatırımlarını artırma, enerji tedarik kaynaklarını çeşitlendirme ve enerji verimliliğini iyileştirme gibi stratejiler hamleler geliştirmektedir. Ancak üye devletlerin farklı ulusal çıkarları, enerji altyapılarındaki uyumsuzluklar, fosil temelli yakıtlara bağımlı halihazırdaki sistemin yüksek maliyetli dönüşümü ve yenilenebilir enerji teknolojilerinin yüksek yatırım gereksinimleri, bu stratejilerin kısa vadede etkili olmasını mümkün kılmamaktadır. 2006, 2009 ve 2014 Ukrayna gaz krizleri ile 2022 Ukrayna Savaşı, AB'nin Rusya'ya bağımlılığının yarattığı politik ve mali riskleri açıkça göstermiş; AB'yi LNG ithalatı ve Norveç, Azerbaycan, ABD gibi alternatif tedarikçilerle enerji ticaretine zorlamıştır. Ancak bu adımlar bağımlılığı ortadan kaldırmak yerine, bağımlılığı farklı coğrafyalara yayarak çeşitlendirmiştir. Sonuç olarak, AB enerjide tam bağımsızlığa erişmek yerine daha dağınık ve yönetilebilir bir bağımlılık modeli üretme çabası içerisindedir. Yenilenebilir enerjiye geçiş, enerji altyapısının bir araya getirilmesi ve yeni tedarik kanallarının kurulması uzun vadeli çözümler yaratırken; siyasi irade, üye ülkeler arası koordinasyon ve ulus üstü yaptırım mekanizmaları kurulmadan bu hedeflerin hayata geçirilmesi güç görünmektedir. Bu bağlamda tez, AB'nin enerji politikalarının yalnızca teknik değil jeopolitik, kurumsal ve stratejik boyutlarıyla ele alınması gerektiğini savunarak literatüre ve politika yapıcılara eleştirel bir çerçeve sunmaktadır. Anahtar Kelimeler: Avrupa Birliği, enerji politikaları, enerji bağımlılığı, Rusya, karşılıklı bağımlılıkAs one of the world's largest e
Irisin Amplifies the Apoptotic Effects of Gefitinib in HepG2 Cells
No full textThis study aims to elucidate the apoptotic effects of irisin in HepG2 cells. We examined the synergistic effects of irisin and gefitinib on the apoptosis of HepG2 cells. The MTT assay was utilized to evaluate the cytotoxic effects induced by irisin or gefitinib. Apoptosis induced by gefitinib, irisin, and their combined treatment was assessed using fluorescence microscopy and flow cytometry. The oxidative stress induced by reactive oxygen species and alterations in cell membrane potential were examined utilizing fluorescence microscopy and flow cytometry. The expression levels of genes associated with growth factors, oncogenes, apoptosis, and multidrug resistance were examined using RT-PCR. The best doses for HepG2 cells were established as 1.57 mu M irisin and 15.66 mu M gefitinib, administered for a length of 48 h. Flow cytometry analysis revealed a significant increase in apoptotic cells following treatment with irisin (16.91%), gefitinib (23.0%), and their combination (38.69%) in comparison to the control group. Furthermore, the proportion of cells impacted by ROS exhibited a notable rise: 8.17% in the irisin-treated cohort, 12.22% in the gefitinib-treated cohort, and 42% in the cohort receiving the combination of gefitinib and irisin. As a result of RT-PCR studies, it was observed that apoptosis was induced following the combination of irisin with gefitinib, and the expression levels of multidrug resistance genes, which were increased in response to gefitinib, were significantly suppressed. The findings of this study indicate that combining irisin with gefitinib could be an effective therapeutic approach against hepatocellular carcinoma.Trakya University's Technology Research and Development Application CenterWe extend our gratitude to Trakya University's Technology Research and Development Application Center (TUTAGEM) for supplying the essential tools and equipment for our laboratory experiments