Uludag University Academic Repository
Not a member yet
50710 research outputs found
Sort by
Seismic fragility assessment of 100 m3 elevated water tanks on shallow foundation considering simplified fluid-structure-soil interaction models
No full textThis study investigates the seismic fragility of typical 100 m3 reinforced concrete elevated water tanks (EWTs) widely constructed across T & uuml;rkiye, many of which remain in service or stand abandoned. A nonlinear modeling framework is employed that incorporates confined material behavior, fluid-structure interaction (FSI), and soil-structure interaction (SSI). The tanks are analyzed under varying conditions, including two concrete strengths (C10-S220 and C20-S420), different reservoir fill levels (empty, half-fill, and full), and multiple soil classes (fixed base, C, D, and D1). A total of 24 three-dimensional finite element models were developed and subjected to nonlinear time-history analyses using 30 ground motion records scaled through the multiple stripe analysis (MSA) method, with spectral acceleration at T = 1.0 s (Sa1) as the intensity measure (IM). Fragility curves were derived using both element-based collapse criteria (single- and double-hinge mechanisms) and driftbased deformation thresholds. Results reveal that tank reservoir level, material strength, and soil condition significantly influence fragility. Full tanks demonstrate lower seismic vulnerability due to increased damping and mass participation, while SSI effects generally reduce seismic demand by elongating structural periods. Higher strength significantly improves seismic performance, particularly under empty or flexible soil conditions. These findings emphasize the need for integrated modeling of fluid-structure-soil interaction (FSSI) phenomena in the seismic evaluation of EWTs, especially for aging or structurally uncertain systems
Developing the social media self-presentation discrepancy scale (smsds): Psychological and social implications of self-presentation and impression management strategies
No full textThis study aimed to develop the Social Media Self-Presentation Discrepancy Scale (SMSDS) to assess individuals' tendencies to present themselves differently from their real selves in social media environments. The theoretical framework of the study was grounded in Goffman's theory of self-presentation, Higgins' self-discrepancy theory, and Leary's impression management model. Through exploratory (n = 243) and confirmatory (n = 409) factor analyses, the scale's structural integrity was established, revealing a three-factor structure comprising Reality Distortion and Exaggeration, Idealized Self-Presentation, and Strategic Impression Management. The scale demonstrated high internal consistency, and its construct validity and measurement invariance were supported through various statistical analyses. The SMSDS offers a functional assessment tool for evaluating psychological aspects of social media use, identifying risky digital behaviors among young users, and designing intervention programs targeting digital self-presentation. The findings contribute to a more comprehensive understanding of the multidimensional nature of self-presentation strategies on social media at both theoretical and applied levels
Wavelet-enhanced multimodel framework for stock market forecasting: A comprehensive analysis across market regimes
No full textIn this study, we develop a hybrid forecasting framework that integrates discrete wavelet transform with multiple machine and deep learning architectures to address nonlinearity and regime-dependent dynamics in financial markets. Log-return series using daily data from the BIST 100, S&P 500, and Shanghai Composite indexes spanning 2015-2025 are subject to three-level Daubechies-4 wavelet decomposition, which yields approximation and detail coefficients that capture multiresolution temporal patterns. Four feature configurations are systematically evaluated: base (lagged returns only), pure wavelet approximation (A1-A3), hybrid wavelet approximation (lags combined with A1-A3), and wavelet approximation-detail (A1-A3 with D1-D3). Random forest, Support Vector Regression, Long Short-Term Memory, and Gated Recurrent Unit models are trained on each configuration, enabling direct assessment of the effectiveness of wavelet feature engineering. A three-state Gaussian hidden Markov model identifies bull, bear, and sideways regimes based on risk-adjusted returns, stratifying out-of-sample results to examine model robustness across varying market conditions without influencing training procedures. Our results demonstrate that wavelet-enhanced configurations, in particular the full approximation-detail specification, reduce forecast errors by 20-40 percent across all indexes and algorithms. Diebold-Mariano tests confirm statistical significance both globally and within each market regime. Our findings confirm that discrete wavelet transform is essential preprocessing for volatile financial markets, offering actionable insights for algorithmic trading, risk management, and policy frameworks in emerging economies
Turkiye century educatıon model: Component-based examination of the secondary education music program
No full textBu çalışma Kütahya Dumlupınar Üniversitesi Güzel Sanatlar Fakültesi Sanat Dergisi Ocak 2026 / Ahmet Yakupoğlu Özel Sayısı'nda yayınlanmıştır.Bu araştırma, (TYMM) kapsamında hazırlanan Ortaöğretim Müzik Dersi Öğretim Programını, müziksel becerilerin yapılandırılması ile modelin temel bileşenleri arasındaki ilişki açısından incelemektedir. Çalışmada beceriler, eğilimler, değerler, okuryazarlıklar ve ölçmedeğerlendirme boyutlarının programdaki yeri ve işleniş biçimi betimlenmektedir. Nitel doküman analizi yöntemiyle, hazırlık sınıfından 12. sınıfa kadar tüm sınıf düzeylerinde yer alan temalar, öğrenme çıktıları ve etkinlik yönergeleri sistematik olarak değerlendirilmiştir. Elde edilen bulgular, programın beceri temelli yaklaşımı merkeze aldığını ve sosyal-duygusal, kültürel ve bilişsel yönelimlerin çeşitli sınıf düzeylerinde değişen biçimlerde ifade edildiğini göstermektedir. Çalışma, yeni öğretim programında müziksel becerilerin yapısını ve temel bileşenler arasındaki ilişkileri bütüncül bir çerçevede ortaya koymakta; ayrıca program geliştirme çalışmalarına katkı sağlayabilecek öneriler sunmaktadır.This study examines the Secondary Education Music Curriculum developed within the scope of the Türkiye Century Education Model issued by the Ministry of National Education, focusing on the relationship between the structuring of musical skills and the core components of the model. The research describes how the dimensions of skills, dispositions, values, literacies, and assessment–evaluation is represented and operationalized within the curriculum. Using a qualitative document analysis method, themes, learning outcomes, and activity guidelines across all grade levels—from the preparatory year to 12th grade—were systematically evaluated. Findings indicate that the curriculum centers on a skill-based approach and that social-emotional, cultural, and cognitive orientations are articulated in varying forms across different grade levels. The study presents a holistic framework for understanding the structure of musical skills and the interrelations among key components within the new curriculum and offers recommendations that may contribute to the further curriculum development efforts
Vibration-based crack diagnosis for asymmetric gears under time-varying operational conditions using a 1-d cnn-lstm model
No full textGearboxes oftentimes operate under time-varying operating conditions (TVOC). Some studies on TVOC assessed the fluctuations in vibration data through computer simulations, while others appraised healthy gearboxes or piecewise constant operating conditions. Besides, these studies all focus on gears with symmetric tooth profiles. From this standpoint, the present experimental study combined a one-dimensional convolutional neural network (1-D CNN) with a long shortterm memory (LSTM) algorithm for diagnosing divergent crack degrees that vary from 0% to 100% with an increment of 25% under TVOC for spur gear pairs with symmetric (20 degrees/20 degrees) and asymmetric (20 degrees/30 degrees) teeth. A series of vibration experiments was performed, considering two TVOC scenarios: (1) variable speed and constant load, and (2) constant speed and variable load. Using an asymmetric profile amplified the amplitude difference between the vibration response of healthy and cracked gears, facilitating fault diagnosis. For different TVOC scenarios, overall accuracies calculated for symmetric gears ranged between 90.005% and 98.654% and between 93.932% and 99.908% for asymmetric ones. The results revealed that the overall classification accuracy could be improved by up to 4.633% using gears with asymmetrical teeth
Dual-representation structural mri classification of psychiatric disorders using deep learning and large language models
No full textAccurate differentiation among psychiatric disorders such as schizophrenia and bipolar disorder remains a significant clinical challenge due to overlapping symptoms and subtle neuroanatomical variations. This study proposes a dual-representation structural MRI framework in which raw T1-weighted MRI slices and their corresponding color-coded tissue segmentation maps-both derived from the same imaging modality-are analyzed using two independently trained ResNet-18 CNNs. The four diagnostic groups examined include Healthy Controls, Schizophrenia Spectrum, Bipolar Disorder with Psychosis, and Bipolar Disorder without Psychosis. TL and DA techniques were employed to address the limited dataset (N= 103). Following model training, a Large Language Model (LLM) was used as a post-hoc analysis tool to contextualize the CNN outputs and provide interpretative insights into the relative contributions of the two MRI-derived representations. The results indicate that the dual-representation approach improves four-way classification performance and enables systematic comparison of structural information captured by raw versus segmentationbased inputs. These findings highlight the potential of combining deep learning models with LLM-assisted interpretability to support more transparent and informative diagnostic tools in psychiatric neuroimaging
Clinical remission and its determinants in adult severe asthma patients receiving biologic therapy: A retrospective analysis
No full textBackground/Objectives: In recent years, the concept of clinical remission under treatment in asthma has gained increasing attention. It is defined as the absence of exacerbations, asthma symptoms, and oral corticosteroid use for at least 12 months, together with improved or stable lung function. This study aimed to evaluate the clinical remission rates and associated factors in patients with severe asthma receiving biologic therapy with either omalizumab (anti-IgE) or mepolizumab (anti-IL-5). Methods: Adult patients with severe asthma and type 2 inflammation who started omalizumab or mepolizumab between January 2009 and December 2023 in our allergy clinic were retrospectively analyzed. Sociodemographic and clinical characteristics were reviewed. Clinical remission rates were assessed at the first and most recent years of maintenance therapy. Independent markers were identified using multivariable analyses. Results: A total of 160 patients were included (mean age 53.8 +/- 14.6 years; 81.9% female). Of these, 85.6% received omalizumab and 14.4% mepolizumab. Remission rates at one year and at the latest follow-up were 60.0% and 43.7%, respectively. Patients achieving remission had higher total IgE levels. Psychiatric comorbidity negatively affected remission. The one-year remission rates were 91.3% in the mepolizumab group and 54.7% in the omalizumab group. Higher baseline blood eosinophil counts and Asthma Control Test (ACT) scores were positive markers, while psychiatric disease was inversely associated. Conclusions: Omalizumab and mepolizumab achieved meaningful clinical remission rates in severe asthma. Elevated ACT scores and eosinophil counts and absence of psychiatric comorbidities were independent markers, underscoring the need for individualized biologic therapy to achieve sustained remission
Analyzing the impact of spatial configuration and function on movement patterns of first-time visitors to historic urban areas: A case study of İznik
No full textThe space syntax approach has been widely used to investigate the impact of spatial configuration on land use and pedestrian movement patterns. Previous research shows that streets with high accessibility are decisive in the location of common functions and pedestrian movement intensities. This study investigates the factors that influence the movement patterns of first-time touristic users. Iznik was chosen as the research area because of its historical buildings from different civilizations, such as the Roman Theater, Hagia Sophia Church, and Nil & uuml;fer Hatun Imaret, and its high tourist value due to the fact that the first ecumenical council took place here. Within the scope of the study, the effects of form and function on users' experiences were investigated by using space syntax and behavioral mapping methods together. The findings show that functions suitable for common use are located on streets with high integration values, but space syntax parameters are not the primary determinant in forming movement schemes. Distinctive functions and historical buildings were practical in determining the movement patterns of users experiencing the city for the first time. The most significant correlation with human movements was calculated in the global choice value among the space syntax parameters
Prognostic value of systemic immune-inflammation index in mucosal malignant melanoma
No full textBackground: Mucosal malignant melanoma (MMM) is a rare and aggressive malignancy with a dismal prognosis. While the Systemic Immune-Inflammation Index (SII) has emerged as a prognostic marker in various solid tumors, its specific value in MMM remains undefined. This study investigated the association between pretreatment SII and overall survival (OS) in patients with MMM. Methods: We retrospectively analyzed 106 adults with histologically confirmed MMM treated at six oncology centers in Turkey between 2005 and 2025. The baseline SII was calculated as platelet x neutrophil/lymphocyte counts obtained before definitive treatment. A receiver operating characteristic (ROC) analysis identified an optimal SII cutoff of 776 for overall survival (OS), defining low (= 776) SII groups. Results: Gastrointestinal and head and neck mucosa were the most frequent primary sites, and one-third of patients presented with metastatic disease. The median OS for the entire cohort was 23.3 months. Patients with a high versus low SII had a shorter OS (16.2 vs. 35.2 months; HR 2.71, 95% CI 1.67-4.40; p < 0.001). In multivariable analysis, a high SII (HR 1.88, 95% CI 1.12-3.14; p = 0.016), gastrointestinal primary site (HR 1.99, 95% CI 1.23-3.23; p = 0.005), and metastatic disease at diagnosis (HR 4.01, 95% CI 2.32-6.94; p < 0.001) independently predicted a worse OS. Conclusions: The SII is a novel, independent prognostic biomarker in MMM. Elevated pretreatment SII correlates with aggressive clinicopathologic features and inferior survival. As a readily accessible and cost-effective marker, SII may facilitate improved risk stratification in routine clinical practice for MMM patients
Perceptions of intensive care nurses regarding open visitation policy in Turkiye: A qualitative study
No full textObjective: Patients' families cannot stay with their relatives in intensive care units (ICUs). Consequently, patients and patients' families experience many problems such as insomnia, anxiety, depression. Due to these situations, the recovery period of patient is prolonged and the quality of life of patients' relatives is decreased. To prevent these problems, open visiting policy in ICUs is recommended. Open visiting policy gives patients' families the opportunity to visit their relatives at any time. This policy is recommended by studies, but is not widely implemented in T & uuml;rkiye. Some reasons are responsible for not applying this policy. The study was conducted to determine the perceptions of intensive care nurses about an open visitation policy. Methods: The study group consisted of 14 intensive care nurses selected through purposive sampling. Data were collected using a semi-structured interview form, and the interviews were recorded with a voice recorder. Data analysis was performed by content analysis. Results: Based on the research results, "opportunity to feel family presence," "barriers to open visitation," and "facilitators of open visitation" themes were identified. Participants generally evaluated the open visitation policy positively. However, it was noted that certain arrangements were needed for the implementation of open visiting policy. Conclusion: Overall, participants favored open visitation; however, consistent with the literature, successful implementation requires structural (single rooms, privacy), staffing and policy arrangements