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Dynamic response of mixed-spin bilayer systems with graphene-like geometry to a time-dependent magnetic field
No full textIn this paper, the dynamic response of a mixed-spin (1/2, 3/2) bilayer graphene-like structure to a time-dependent magnetic field is investigated using dynamic mean-field theory (MFT). The dynamic equations are derived via Glauber transition rates and solved using Adams-Moulton and Romberg integration methods. The effects of Hamiltonian parameters on the system's dynamic behavior are thoroughly analyzed. The system exhibits various types of dynamic compensation behavior (P, Q, N, S, R, and L-type), each reflecting distinct magnetization reversal mechanisms under oscillating fields. Dynamic phase diagrams in the reduced temperature–magnetic field plane reveal both fundamental phases (F, P, C, NM) and mixed phases (C+P, F+P, F+NM, NM+P, F+C), along with reentrant transitions and multicritical points such as the dynamic double critical end point (B) and the dynamic triple point (TP). These findings highlight the rich dynamic behavior of the system and its sensitivity to external field parameters, offering insights into the design of tunable magnetic materials
Analytical approaches to the Kaup-Newell model in mathematical physics
No full textThis study investigates the Kaup-Newell equation, a nonlinear Schr & ouml;dinger-type model with important applications in plasma physics and nonlinear optics, particularly in modeling sub-picosecond pulses. By employing the modified direct algebraic method and the advanced exp(-Xi(xi))-expansion method, we derive a broad spectrum of soliton solutions, including hyperbolic, trigonometric, shock, singular, and mixed types. These solutions, validated using Maple software, enhance the understanding of nonlinear wave behavior. Additionally, the energy balance method is applied to examine traveling wave dynamics, yielding periodic solution in cosine form. Graphical representations in 2D, 3D, and contour plots are provided to visualize the solution profiles. The results not only demonstrate the efficacy of the proposed methods but also contribute novel insights into the Kaup-Newell model, with potential applicability to a wider class of nonlinear partial differential equations
Neurocomputing capability evaluation of FHN model-based MSNN architectures with different window functions through the XOR problem
No full textThis study focuses on utilizing Memristive Spiking Neural Network (MSNN) structures based on the Fitzhugh-Nagumo (FHN) neuron model coupled with the Voltage ThrEshold Adaptive Memristor (VTEAM), and constrained by five different window functions, to solve the Exclusive OR (XOR) problem through both numerical simulations and real-time hardware implementations. Specifically, two input and two output neurons have been constructed as the 2 × 2 MSNN architectures, and the Joglekar, Biolek, Strukov, Prodromakis, and Blackman window functions define their memristor models. The optimal memductance values for synaptic connections in these five network configurations are set using the Spike-Timing-Dependent Plasticity (STDP) learning rule combined with the Winner-Takes-All (WTA) algorithm. The performance of these networks is evaluated based on their efficiency in solving the XOR problem. In this context, the XOR problem has been conducted as an image formed by a 2-pixel array. These pixels are transmitted as noisy signals from the MSNN input layer, where input neurons convert them into spike activities. These spike activities are then integrated through the memristive synapse layer and forwarded to the output layer as excitatory current signals, enabling the output layer to classify the input correctly. The simulation and Field-Programmable Gate Array (FPGA) hardware implementation results exhibit strong consistency. This work demonstrates, for the first time, the capacity of MSNNs to solve nonlinear problems by providing both simulation-based and hardware-based solutions to the XOR problem using various MSNN architectures with different window functions
Students' Experiences with Robotics Coding Activities
No full textRobotic coding activities help to concretize abstract scientific concepts, develophigher-order skills such as problem-solving and critical thinking, and provide studentswith opportunities to observe, formulate hypotheses, design experiments, and analyzedata. Therefore, this study has chosen robotic coding activities as its research area.This study aimed to determine the opinions of eighth-grade middle school students onArduino-based robotic coding activities integrated into science topics. This studyemploys a case study based on a qualitative research design. This research employedcriterion sampling to select participants. The study group consists of five eighth-gradestudents studying at a public school. Researchers preferred a 13-question semistructured interview as a data collection tool. The interviews were conducted face-toface and online via Zoom by the third researcher. Interview data were analyzed usingcontent analysis. Participants were informed about the activities under the guidance ofthe school and their families. Participants preferred Arduino-based robotic codingactivities because of their connection to daily life. Five participants indicated theywanted to learn science topics through Arduino-based robotic coding activitiesbecause it facilitated meaningful learning. Participants stated increased motivation forscience topics due to Arduino activities and noted that collaborative work improvedtheir experiences. The authors argue that family guidance requires further research.Activities should be designed considering students' differences and interests.Interactive activities within the constructivist learning paradigm are necessary forstudents to manage their learning processes effectively. Additionally, conflicts thatarise during group work enhance students' problem-solving and critical thinking skills.</p
ŞİDDETLİ İSKELETSEL VE DENTOALVEOLAR SINIF II MALOKLÜZYONA SAHİP GENÇ ERİŞKİN BİR HASTANIN DÖKÜM HERBST AYGITI İLE TEDAVİSİ: OLGU SUNUMU
No full textAMAÇ: Bu olgu sunumunun amacı, şiddetli iskeletsel ve dentoalveolar Sınıf II Bölüm 1 maloklüzyona sahip genç erişkin bireyde, Herbst aygıtı ile başlatılan ve ardından sabit ortodontik tedavi ile sürdürülen tedavi yaklaşımının klinik sonuçlarını değerlendirmektir. GEREÇ-YÖNTEM: Tedavi başlangıcında dişlerinin arasındaki boşluklar, alt dişlerinin damağına vurması ve alt çenesinin geride olması şikayetiyle kliniğimize başvuran, kronolojik yaşı 17 yıl 3 ay olan erkek hastanın klinik muayenesinde belirgin artmış overbite (8 mm) ve overjete (11 mm), Angle Sınıf II bölüm 1 maloklüzyona ve konveks profile sahip olduğu gözlemlenmiştir. Hastanın sefalometrik değerlendirmesinde mandibular retrognatiye bağlı olarak iskeletsel Sınıf II malokluzyona (SNA:78,1°, SNB:73°, ANB:5,1° ) ve azalmış dik yön boyutlarına (SN-GoGn: 19,6°) sahip olduğu belirlenmiştir. Dişsel ölçümlerde ise U1-PP açısının 122,3° ve IMPA açısının 94,5° olduğu tespit edilmiştir. Hasta ortognatik cerrahi tedavi planını reddetmiştir. Rölatif maksiller darlık nedeniyle ekspansiyon vidası içeren döküm Herbst aygıtı uygulamıştır. Hızlı üst çene genişletme protokolü kapsamında 30 günlük (20 tur) aktivasyon periyodunun ardından döküm Herbst aygıtı aktive edilmiştir. 10 aylık Herbst apareyi ile yapılan fonksiyonel tedavi sürecini takiben, 13 ay süreyle sabit ortodontik tedavisine devam edilmiştir ve sonrasında retansiyon fazına geçilmiştir. BULGULAR: Döküm Herbst aygıtı ile yapılan fonksiyonel tedavi sonrası alınan ara kayıtlarda yapılan sefalometrik değerlendirme sonucunda SNA açısının 78,3, SNB açısının 77,5°, ANB açısının 0,8° ve SN-GoGn açısının 20,2° olduğu belirlenmiştir. Dişsel ölçümlerde ise U1-PP açısının 116,7° ve IMPA açısının 96° olduğu tespit edilmiştir. Hastanın sabit ortodontik tedavisi tamamlandıktan sonra yapılan sefalometrik değerlendirmede SNA açısının 78,7°, SNB açısının 77,1°, ANB açısının 1,6° ve SN-GoGn açısının 22,6° olduğu belirlenmiştir. Dişsel ölçümlerde ise U1-PP açısının 106,4° ve IMPA açısının 96,9° olduğu tespit edilmiştir. SONUÇ: Şiddetli iskeletsel ve dentoalveolar sınıf II maloklüzyona sahip genç erişkin hastada döküm Herbst aygıtı ile uygulanan tedavi mandibular retrognatinin iskeletsel düzeyde düzeltimini, yüz profilinin iyileştirilmesini ve dişsel maloklüzyonunun düzeltimini sağlamıştır.AIM: This case report aims to evaluate the clinical outcomes of a treatment protocol initiated with a cast Herbst appliance and followed by fixed orthodontic therapy in a young adult patient with severe skeletal and dentoalveolar Class II Division 1 malocclusion. MATERIAL-METHOD: A 17-year and 3-month-old male patient presented to our clinic with complaints of interdental spacing, palatal impingement of lower incisors, and mandibular retrusion. Clinical examination revealed a significantly increased overbite (8 mm) and overjet (11 mm), an Angle Class II Division 1 malocclusion, and a convex facial profile. Cephalometric evaluation indicated a skeletal Class II relationship due to mandibular retrognathia (SNA: 78.1°, SNB: 73°, ANB: 5.1°) and reduced vertical facial dimension (SN-GoGn: 19.6°). Dental measurements showed a U1-PP angle of 122.3° and an IMPA of 94.5°. The patient declined orthognathic surgery. Due to relative maxillary constriction, a cast Herbst appliance with an expansion screw was applied. Following a 30-day (20 turns) rapid maxillary expansion protocol, the appliance was activated. After 10 months of functional treatment with the Herbst appliance, fixed orthodontic treatment continued for 13 months, followed by the retention phase. RESULTS: Cephalometric evaluation after functional treatment with the cast Herbst appliance revealed values of SNA: 78.3°, SNB: 77.5°, ANB: 0.8°, and SN-GoGn: 20.2°. Dental measurements showed a U1-PP angle of 116.7° and IMPA of 96°. Upon completion of fixed orthodontic therapy, f inal cephalometric records showed SNA: 78.7°, SNB: 77.1°, ANB: 1.6°, and SN-GoGn: 22.6°, with dental parameters of U1-PP: 106.4° and IMPA: 96.9°. CONCLUSION: In treating a young adult with severe skeletal and dentoalveolar Class II malocclusion, use of a cast Herbst appliance achieved favorable skeletal correction of mandibular retrognathia, facial profile improvement, and successful resolution of dental malocclusion.</p
