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Online Tuning Mechanism for Single Input Interval Type-2 Fuzzy PID Controller
No full textIn this study, an online tuning mechanism for single-input interval type-2 fuzzy PID (OTM-SIT2-FPID) controller has been designed. Interval type-2 fuzzy logic controllers exhibit better performance due to the footprint of uncertainty (FOU) in their interval type-2 fuzzy sets (IT2-FSs). In our study, the FOU was dynamically adjusted online by defining a function which consists of the system error. The system error serves as the input to the OTM-SIT2-FPID controller, while the control signal represents its output. Input variables of the proposed controller are defined by the three triangular interval type-2 fuzzy membership functions, whereas its output variables are characterized by three singleton membership functions. To assess the performance of the proposed controller (OTM-SIT2-FPID), both a single-input interval type-2 fuzzy PID (SIT2-FPID) and a PID controller were also designed. Simulation studies conducted on a nonlinear system under output disturbances demonstrate that the OTM-SIT2-FPID controller exhibits superior robustness and performance compared to the SIT2-FPID and conventional PID controllers
Glutensiz Şekerpare Üretiminde Farklı Un Çeşitleri, Protein Kaynakları ve Transglutaminaz Enziminin Etkileri
No full textŞekerpare, Türkiye ve Orta Doğu mutfağının önemli tatlılarından biri olup, genellikle irmik kullanılarak hazırlanmaktadır. Ancak irmiğin gluten içermesi, çölyak hastalarının bu tatlıyı tüketmesini engellemektedir. Bu çalışmada, gluten içermeyen mısır unu, pirinç unu, patates unu, mısır nişastası ve tapyoka nişastası kombinasyonları kullanılarak glutensiz şekerpare formülasyonları geliştirilmiştir. Ayrıca, bu formülasyonlara eklenen soya proteini, bezelye proteini ve transglutaminaz (TG) enziminin şekerpare hamuru ve son ürün özellikleri üzerindeki etkileri incelenmiştir. Çalışma kapsamında, hamurların pH, sertlik, yapışkanlık, adhezyon işi ve hamur kuvveti gibi özellikleri değerlendirilirken son ürünlerde ise renk, sertlik, kırılganlık ve duyusal analizler gerçekleştirilmiştir. Elde edilen sonuçlar, kullanılan protein ve TG enziminin hamur özellikleri üzerindeki etkisinin kullanılan un kombinasyonuna bağlı olarak değiştiğini göstermiştir. Mısır ve patates unu ile hazırlanan hamurlar en yüksek sertlik değerine sahipken, tüm örneklerde kontrol grubu hamurları en düşük sertlikte olmuştur. Soya ve bezelye proteini, hamurun yapışkanlığını azaltırken, TG enziminin bezelye proteiniyle birlikte kullanımı yapışkanlık düzeyini önemli ölçüde artırmıştır. Duyusal analizde panelistler, %62,5 mısır unu ve %37,5 pirinç unundan oluşan MuPr reçetesiyle hazırlanan şekerpare örneklerini, hem yapı hem de lezzet açısından en beğenilen ürün olarak değerlendirmiştir. Bununla birlikte, kullanılan protein türü ve TG enzimi duyusal özellikler üzerinde genel anlamda önemli bir fark yaratmamıştır.Şekerpare is a well-known dessert in Turkish and Middle Eastern cuisine, traditionally prepared using semolina. However, the presence of gluten in semolina prevents individuals with celiac disease from consuming this dessert. In this study, gluten-free şekerpare formulations were developed using combinations of corn flour, rice flour, potato flour, corn starch, and tapioca starch. Additionally, soy protein, pea protein, and transglutaminase (TG) enzymes were incorporated into these formulations to investigate their effects on dough and final product properties. The study evaluated the properties of the dough, such as pH, hardness, stickiness, work of adhesion, dough strength/cohesiveness, and the color, hardness, fracturability, and sensory properties of the final products. The results demonstrated that the proteins and TG enzyme had varying effects on dough properties depending on the flour combination used. Dough prepared with corn and potato flours exhibited the highest hardness values, while the dough of control group consistently had the lowest hardness. Soy and pea proteins reduced the stickiness of the dough, whereas the use of TG enzyme in combination with pea protein significantly increased the stickiness levels. In the sensory analysis, panelists rated the şekerpare samples prepared using the MuPr formulation, consisting of 62,5% corn flour and 37,5% rice flour, as the most preferred product in terms of texture and taste. However, it was observed that the type of protein used and the addition of TG enzyme did not have a significant overall impact on sensory attributes.</p
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No full textThe effect of stiffeners on asymmetric (UPN) beams under eccentric loads
No full textStiffeners are crucial in enhancing the resistance of steel elements to both point and distributed vertical loads. However, one of the main challenges is the vertical and horizontal deflection experienced by steel beams under asymmetric loading conditions. This study investigates, using IDEA StatiCa software, the effect of stiffeners on the performance of European UPN steel beams subjected to eccentric point loads. A total of 12 beam models stiffened and unstiffened were studied, varying in height and yield strength. Finite element analysis was conducted using the Component-Based Finite Element Method (CBFEM) to accurately capture stress distribution and deflection behavior. The results show that stiffeners significantly reduce both vertical and lateral deflections and improve torsional stability. Furthermore, stiffened and unstiffened beams reached yield strength at similar load levels, but the presence of stiffeners limited post-yield deformations. The findings align with previous studies and confirm the value of stiffeners in enhancing the structural performance of asymmetric beams. This highlights the practical importance of stiffeners in UPN steel beam design, especially under eccentric loading where stability and local deformation are critical concerns
First measurement of D*+ vector meson spin alignment in Pb–Pb collisions at TeV
No full textThe first measurement of prompt D*+-meson spin alignment in ultrarelativistic heavy-ion collisions with respect to the direction orthogonal to the reaction plane is presented. The spin alignment is quantified by measuring the element ρ00 of the diagonal spin-density matrix for prompt D*+ mesons with 4 1/3 has been found for pT> 15 GeV/c and 0.3 < |y| < 0.8 with a significance of 3.1σ. The measured spin alignment of prompt D*+ mesons is compared with the one of inclusive J/ψ mesons measured at forward rapidity (2.5 < y < 4)
Enhancing QR code security: Exploiting hidden message mechanisms and machine learning classification
No full textThe degree of utilization of Quick Response (QR) codes is sharply increasing due to the wide availability of smart devices. The primary purpose of the QR code is to ensure that an extensive message is fully transferred in a compact data format. Like any environment, security is an essential issue where QR codes are utilized. Such problems include the lack of signing information in a QR. This study aims to exploit the QR code hiding mechanism without spoiling the value of the code in the QR code while determining it using several machine learning algorithms. Consequently, several new QR image datasets are generated with varying sizes and variations to examine the classification of the proposed message-hiding scheme. This study used state-of-the-art models (VGG16, Xception) and a CNN-based model for QR code classification but only achieved 50% accuracy across four QR code dataset variants. Unsatisfied with these results, the study then employed the histogram feature density technique with various machine-learning (Logistic Regression (LR), Decision Tree (DT), and Random Forest (RF)) and deep learning (DL) models. The experimental results reveal that adapting the histogram density method in the proposed scheme for feature creation achieved an overall success rate of approximately 99.98%. Moreover, the study further aims to simulate single-layer QR codes from hackers’ perspective that pretends to look like two-layer QR code systems. As a result of this simulation study, the performance was tested using different classification algorithms. In most cases, except for one, the DL model performed better by attaining a success rate above 90%
Production, characterization, and biocompatibility of polycaprolactone/polylactic acid coaxial nanofiber patches based on bacterial cellulose from orange peels
No full textPolycaprolactone (PCL) /polylactic acid (PLA) coaxial electrospun nanofiber patches were produced with bacterial cellulose (BC) obtained by recycling orange peels, and their effect on human dermal fibroblast cell line was investigated. Biodegradable nanofibers composed of PLA and PCL are frequently used in biomedical applications due to their favorable mechanical and biocompatible properties. However, the incorporation of bioactive molecules such as ascorbic acid and the integration with a non-synthetic polymer such as bacterial cellulose can enable a new and different focus on the interaction with PCL/PLA. The produced coaxial nanofiber patches were compared based on two different BC concentrations and the presence or absence of ascorbic acid. In the coaxial structure, the core layer consisted of PCL/PLA, while the shell layer was composed of BC. Scanning electron microscopy (SEM) analysis revealed that the thickest fibers were observed in the pure PCL/PLA nanofiber patches, whereas the addition of ascorbic acid led to a noticeable reduction in fiber thickness. Furthermore, increasing the BC ratio resulted in a higher incidence of fiber breakage. According to the swelling and degradation test results, BC increased the swelling capacity of the material, while PCL/PLA slowed down the biodegradation rate. The coaxial nanofiber structure, with BC as the shell and PCL/PLA as the core, exhibited biocompatibility by supporting dermal cell viability, proliferation, and adhesion over 1, 4, and 7 days of observation
INTEGRAL INEQUALITIES FOR (h, m)- CONVEX FUNCTIONS VIA VARIABLE-ORDER FRACTIONAL CALCULUS
No full textCognitive Skills and Employment Status: Is There a Gender Difference?
No full textThis paper examines the gender differences in the association between cognitive skills and employment status. Using data from the Socio-Economic Panel (SOEP) spanning 2003–2019, we measure cognitive skills through the Symbol Digit Test (SDT), administered in three waves and assumed to be time-invariant. Our findings reveal a prominent and statistically significant positive relationship between cognitive skills and employment probability, with considerable gender disparities. In particular, the returns to cognitive skills are consistently higher for men. These results remain robust across different estimation methods and hold when considering both time-invariant and time- variant cognitive skills. We explore potential mechanisms driving these patterns, including social norms and individual heterogeneity.</p
