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Article Citation - Scopus: 3Complete Characterization of a Class of Permutation Trinomials in Characteristic Five(Springer, 2024) Grassl,M.; Özbudak,F.; Özkaya,B.; Temür,B.G.In this paper, we address an open problem posed by Bai and Xia in [2]. We study polynomials of the form f(x)=x4q+1+λ1x5q+λ2xq+4 over the finite field F5k, which are not quasi-multiplicative equivalent to any of the known permutation polynomials in the literature. We find necessary and sufficient conditions on λ1,λ2∈F5k so that f(x) is a permutation monomial, binomial, or trinomial of F52k. © The Author(s) 2024.Article Knee Hyperextension in Chronic Stroke: Associated Biomechanical and Neuromuscular Factors(Elsevier Sci Ltd, 2025) Korkusuz, Sueleyman; Korkusuz, Busra Seckinogullari; Ozgoren, Nihat; Aritan, Serdar; Ceren, Ali Naim; Topcuoglu, Mehmet Akif; Balkan, Ayla FilBackground: This study aimed to determine the gait phase in which knee hyperextension occurs in stroke patients and to investigate the factors associated with knee hyperextension. Methods: This study included 30 stroke patients aged between 40 and 70 years with maximum knee hyperextension during the stance phase of gait. Muscle strength was evaluated with manual muscle test, and muscle tone was assessed with the Modified Ashworth Scale. Kinematic evaluation of the patients was made using the motion analysis system. Additionally, categorisation was made according to the stance phase of gait, where knee hyperextension was at its highest. Findings: A weak relationship was found between maximum knee hyperextension angle and gastrocnemius spasticity, a moderate relationship between knee flexor muscle strength, and a moderate relationship between ankle dorsiflexor muscle strength. In addition, a weak relationship was found between the maximum knee hyperextension and pelvic retraction angles. According to this clustering, it was observed that 66.67 % of the participants (20 people) showed maximum knee hyperextension in the single support phase. It was observed that the participants who had maximum knee hyperextension, especially after the mid-stance phase, had higher mean gastrocnemius spasticity. It was also observed that participants in Cluster 4, with a greater amount of maximum knee hyperextension, had the worst clinical parameters. Interpretation: Our study observed that the degree of maximum knee hyperextension was related to knee flexor and ankle dorsiflexor muscle strengths, gastrocnemius spasticity and pelvic retraction. As clinical parameters worsened, maximum knee hyperextension was thought to occur late in the stance phase. Clinical Trial code: NCT05679700Article Recognition and Misclassification Patterns of Basic Emotional Facial Expressions: An Eye-Tracking Study in Young Healthy Adults(MDPI, 2025) Alkan, NeşeAccurate recognition of basic facial emotions is well documented, yet the mechanisms of misclassification and their relation to gaze allocation remain under-reported. The present study utilized a within-subjects eye-tracking design to examine both accurate and inaccurate recognition of five basic emotions (anger, disgust, fear, happiness, and sadness) in healthy young adults. Fifty participants (twenty-four women) completed a forced-choice categorization task with 10 stimuli (female/male poser x emotion). A remote eye tracker (60 Hz) recorded fixations mapped to eyes, nose, and mouth areas of interest (AOIs). The analyses combined accuracy and decision-time statistics with heatmap comparisons of misclassified versus accurate trials within the same image. Overall accuracy was 87.8% (439/500). Misclassification patterns depended on the target emotion, but not on participant gender. Fear male was most often misclassified (typically as disgust), and sadness female was frequently labeled as fear or disgust; disgust was the most incorrectly attributed response. For accurate trials, decision time showed main effects of emotion (p < 0.001) and participant gender (p = 0.033): happiness was categorized fastest and anger slowest, and women responded faster overall, with particularly fast response times for sadness. The AOI results revealed strong main effects and an AOI x emotion interaction (p < 0.001): eyes received the most fixations, but fear drew relatively more mouth sampling and sadness more nose sampling. Crucially, heatmaps showed an upper-face bias (eye AOI) in inaccurate trials, whereas accurate trials retained eye sampling and added nose and mouth AOI coverage, which aligned with diagnostic cues. These findings indicate that the scanpath strategy, in addition to information availability, underpins success and failure in basic-emotion recognition, with implications for theory, targeted training, and affective technologies.Article Citation - WoS: 2Citation - Scopus: 1Oscillation of Impulsive Linear Differential Equations With Discontinuous Solutions(Cambridge University Press, 2023) Doǧru Akgöl,S.Sufficient conditions are obtained for the oscillation of a general form of a linear second-order differential equation with discontinuous solutions. The innovations are that the impulse effects are in mixed form and the results obtained are applicable even if the impulses are small. The novelty of the results is demonstrated by presenting an example of an oscillating equation to which previous oscillation theorems fail to apply. © The Author(s), 2022. Published by Cambridge University Press on behalf of Australian Mathematical Publishing Association Inc.Article Citation - WoS: 3Citation - Scopus: 3Modeling and Measurement of Human Body Blockage Loss at 28 Ghz(Taylor & Francis Ltd, 2023) Benzaghta, Mohamed; Gokdogan, Bengisu Yalcinkaya; Coruk, Remziye Busra; Kara, AliMillimeter-wave (mm-Wave) spectrum is an essential enabler to the fifth generation (5G) wireless technology. Humans are one of the most noticeable blockers that cause temporal variation in indoor radio channels. This paper presents human blockage measurements at 28 GHz, with several humans of different sizes. The effect of the crossing orientations of the human bodies is investigated for three different transmitter heights. A human blockage model based on the Fresnel diffraction scheme is shown to be applicable in estimating the human blockage loss in indoor radio links considering various body sizes, different crossing orientations, and different transmitter heights. The findings reported in this paper could help improve indoor radio channel models at 28 GHz bands for 5G technologies considering the presence of human body blockages.Article Citation - WoS: 4Citation - Scopus: 4A Site Survey of Damaged Rc Buildings in Izmir After the Aegean Sea Earthquake on October 30, 2020(Croatian Soc Civil Engineers-hsgi, 2023) Mertol, Halit Cenan; Tunc, Gokhan; Akis, TolgaAn earthquake with a magnitude of Mw = 6.6 and a depth of approximately 16.5 km occurred on 30 October 2020 off the cost of Samos, a Greek island 35 km southwest of Seferihisar, a town in Izmir. The earthquake caused several collapses and severe structural damage in approximately 6,000 buildings, specifically in the Bayrakli District in Izmir Bay. This paper presents the observations and findings of a technical team that visited the earthquake -affected areas immediately after the earthquake. Eleven partially or fully collapsed and several severely damaged reinforced concrete buildings were investigated. Based on the site investigations, we observed that almost all of the collapsed or severely damaged reinforced concrete buildings in the region were built between 1975 and 2000. Site observations also confirmed that the construction of these collapsed or damaged buildings did not conform to the requirements outlined in the Turkish Earthquake Codes used at the time. The failures and severe damage to buildings in earthquake-affected areas are primarily related to inadequate reinforcement configuration, poor material quality, the absence of geotechnical studies, and framing problems related to their lateral load-carrying systems. Therefore, it is recommended that all the buildings located in and around Izmir Bay, particularly those built between 1975 and 2000, be structurally evaluated to prevent any further loss of life and property during future earthquakes.Article A Class of Shock Models for a System That Is Equipped With a Protection Block With an Application to Wind Turbine Reliability(Wiley, 2025) Eryilmaz, SerkanThis paper studies a class of shock models for a system that is equipped with a protection block that has its own failure rate. Under the considered class, the system exposed to shocks at random times is protected by the protection block, and the probability of the shock damaging the system varies depending on whether the protection block operates or not. The system failure criteria is defined based on the pattern of the critical/damaging shocks. Exact expressions for the reliability and mean time to failure of the system are obtained, and detailed computations are presented for the run shock model, which is included in the class. The application of the extreme shock model, which is included in the relevant class, to wind turbine reliability is also discussed.Article Red Vienna: Ideology, Architecture and Art in the Reumannhof Municipal Social Housing(Middle East Technical Univ, 2024) Pfeiffer Tas, Sule; Temel, RabiaThis study focuses on the Reumannh of Social Housing Complex, which was designed by Hubert Gessner (1871-1943) and constructed between 1924 and 1926 in Vienna. It was one of the largest buildings as part of the Municipal Social Housing Program for workers implemented under the leadership of Jakob Reumann, who was the mayor of Vienna between 1919 and 1923. According to the social democratic ideology in Vienna, known as the Red Vienna period (1919-1934) of the city administration, this program aimed to meet the housing needs of the working class and to provide them with better living conditions. Due to the increase in worker migration to the city after the Industrial Revolution and upon the demolition of the city during World War I, a housing crisis emerged in Vienna and unfavorable living conditions - such as one-room apartments and rental beds even for a few hours - became a necessity. The paper attempts to probe into the nature of the connection between the Reumannh of Complex architecture and the Red Vienna ideology in light of the social democratic perspective of the working class. In order to do so, the entire structure - known as "the palace of the working class" - is analyzed in detail while pointing to similar social housing complexes, such as Metzleinstalerh of on the Margareteng & uuml;rtel known as "Proletarian's Boulevard" and nearby. Additionally, the standardization criteria, as envisioned within the context of the social housing program, are examined to find out any traces of their presence (or improvements/modifications upon them) in the Reumannh of Complex. In the context of the political and socio-economic conditions of that era, a comparative analysis of the architectural elements and landscape architecture is conducted, such as courtyards and Haydn park on the front in the latter case. Original archival documents, photographs, and drawings of the complex were collected and during the course of the field research, photographs were taken. A housing typology and drawings were made in accordance with the general floor plan of the building, drawn by Gessner himself to determine the details related to the features of the houses - such as kitchen, living room+kitchen, and the number and function of the rooms - in order to determine the reflection of the living comfort promised by the social democratic ideology. As a result, three main plan types were identified based on the spaces contained within the houses, and subgroups were created according to balconies, terraces, or bay windows, all of which provided daylight and fresh air. In conclusion, the research establishes that the Reumannhof Complex houses, common facilities as terraces, infant school, laundry rooms, etc. all implemented standards that were mostly aligned with those related to welfare and in line with the principles of social democratic ideology. Lastly, it is revealed that architectural and artistic elements, such as wrought iron, ceramic panels illustrating craftsmen and different professions, motifs, and sculptures, not only reflect the social democratic ideology and motto, but also create new living environments by integrating architectural design with green spaces for the working class. As witness to this assertion, it is useful to notice that the complex still serves the function of economic housing for the working class and remains important as a symbol of social democratic ideology.Article Citation - Scopus: 1Determining the Hydrogen Production Potential of Conmo6se8 Chevrel Phases(Institute of Physics, 2025) Gencer, A.; Surucu, O.; Sahin, M.; Ozel, F.; Surucu, G.In this study, the ConMo6Se8 (n = 1, 2, 3, and 4) Chevrel phases are investigated by using Density Functional Theory (DFT) to reveal their potential for photocatalytic hydrogen production. The stability conditions of these phases reveal that CoMo6Se8, Co2Mo6Se8, and Co3Mo6Se8 satisfy the thermodynamic and mechanic stability properties, while Co4Mo6Se8 does not satisfy any of these properties. Furthermore, the formation enthalpy of these phases shows that CoMo6Se8, Co2Mo6Se8, and Co3Mo6Se8 can be synthesized experimentally due to having negative formation enthalpy values. Furthermore, the thermal stabilities of the machine-learning (ML) force fields are investigated by ab-initio molecular dynamics (AIMD) calculations. The electronic properties of these phases are also investigated in detail, and it is found that Co3Mo6Se8 has a suitable band gap for photocatalytic water splitting. Concerning the investigation of the valence band and conduction band levels, it is shown that Co3Mo6Se8 has a conduction band minimum level suitable for producing hydrogen. This study is the first attempt to reveal the hydrogen production performance of the ConMo6Se8 (n = 1, 2, 3, and 4) Chevrel phases as far as the literature is concerned, paving the ground for future investigations in this field. © 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.Article Citation - WoS: 2Citation - Scopus: 2Enhancing Classification Modeling Through Feature Selection and Smoothness: a Conic-Fused Lasso Approach Integrated With Mean Shift Outlier Modelling(Amer inst Mathematical Sciences-aims, 2025) Yerlikaya-Ozkurt, Fatma; Taylan, PakizeOutlier detection and variable selection are among main objectives of statistical analysis. In our study, we address the outlier problem for classification by using the Mean Shift Outlier Model (CLMSOM). Since the MSOM has more coefficients than the linear regression model, the complexity of the model MSOM is high. Therefore, we consider feature selection for MSOM by using fused Lasso (FLasso), which is beneficial and helpful in the cases where the number of explanatory variables or features is greater than the sample size. FLasso is penalizing both the coefficients and their successive differences by the L-1-norm, and it allows sparsity for both of them, while Lasso only allows the coefficients by considering a nonsmooth optimization problem. In this study, we take into account Iterated Ridge approximation which enables us to use a smooth optimization for FLasso problem. Generated smooth optimization problem is solved by using one of continuous optimization techniques called Conic Quadratic Programming (CQP), which is enabling the utilization of interior point methods. The newly developed method is called Conic FLasso for classification by MSOM (C-FLasso-CLMSOM) and is applied to real world data set to show its performance.