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  • Article
    Citation - WoS: 0
    Citation - Scopus: 0
    Estimation of the Mean Radiant Temperature in Office Buildings Using an Artificial Neural Network Developed in a Phyton Environment
    (Taylor & Francis Ltd, 2025) Ozbey, Mehmet Furkan; Lotfi, Bahram; Turhan, Cihan
    Thermal comfort describes an occupant's state of mind in a thermal environment, influenced by six parameters: air velocity, relative humidity, air temperature, mean radiant temperature (MRT), clothing value, and metabolic rate. MRT is the most problematic parameter since the obtaining process is difficult and time-consuming. MRT can be acquired by several methods such as calculations, measurements, assumptions, and software programmes. However, the methods have complexities and uncertainties. Comprehensive models are needed to obtain MRT. To this aim, this study presents an alternative method using one of the artificial intelligence methods, Artificial Neural Network (ANN), to predict MRT for indoor environments to abstain from the difficulties and complexities. A case building is selected in a university office building in Ankara, T & uuml;rkiye. The proposed model is developed and coded in a Python programming environment to predict the MRT using ANN. The results indicate that the ANN model, using only four inputs, predicts MRT with an R-2 value of 0.94 compared to the globe thermometer measurement method. The model's advantages over methods include simplicity, time efficiency and learning from the limited datasets such as difficulty in calculating terms like MRT.
  • Article
    Citation - WoS: 0
    Neopatrimonial Rule Through Formal Institutions: the Case of Turkey
    (Cambridge Univ Press, 2025) Bektas, Eda
    This study examines how formal institutions in hybrid regimes, particularly presidentialism, party organization and electoral rules, actively foster and sustain clientelistic networks, leading to particularistic outcomes. While existing literature highlights the weakening of formal institutions and pervasive clientelism as drivers of democratic breakdown, this study uses the concept of neopatrimonialism to analyse how formal institutions themselves consolidate patron-client relationships to maintain power and stability. Focusing on Turkey, the analysis demonstrates that the institutional incentive structure consolidates the president's role as the central 'patron', controlling resources and offices, and encourages clientelistic networks to coalesce around the presidency. The discretionary allocation of resources through patron-client relationships sustains neopatrimonial authority as long as clients' loyalty is rewarded. However, this governance increases clients' dependence on the patron, binding them at the expense of representation and responsiveness. The analysis offers insights into how such institutional configurations contribute to authoritarianism and particularistic governance in hybrid regimes.
  • Article
    Citation - WoS: 0
    Citation - Scopus: 0
    Physics-Informed Neural Network for Bending Analysis of Twodimensional Functionally Graded Nano-Beams Based on Nonlocal Strain Gradient Theory
    (Univ Tehran, Danishgah-i Tihran, 2025) Esfahani, Saba Sadat Mirsadeghi; Fallah, Ali; Aghdam, Mohammad Mohamadi
    This paper presents the bending analysis of two-dimensionally functionally graded (2D FG) nano-beams using a physics-informed neural network (PINN) approach. The material properties of the nanobeams vary along their length and thickness directions, governed by a power-law function. Hamilton's principle, combined with the nonlocal strain gradient theory (NSGT) and Euler-Bernoulli beam theory, is employed to derive the governing equation for the bending analysis of 2D FG nanobeams. Due to the incorporation of size dependency and the variation of material properties in two dimensions, the governing equation becomes a high-order variable- coefficient differential equation, which is challenging, if not impossible, to solve analytically. In this study, the applicability of PINN for solving such high-order complex differential equations is investigated, with potential applications in nanomechanical engineering. In the PINN approach, a deep feedforward neural network is utilized to predict the mechanical response of the beam. Spatial coordinates serve as inputs, and a loss function is formulated based on the governing equation and boundary conditions of the problem. This loss function is minimized through the training process of the neural network. The accuracy of the PINN results is validated by comparing them with available reference solutions. Additionally, the effects of material distribution, power-law index (in both length and thickness directions), nonlocal strain gradient parameters, and material length scale parameters are investigated. This study demonstrates the versatility of the PINN approach as a robust tool for solving high-order differential equations in structural mechanics.
  • Article
    Citation - WoS: 0
    Citation - Scopus: 0
    A Model-Based Evaluation Metric for Question Answering Systems
    (World Scientific Publ Co Pte Ltd, 2025) Bakir, Dilan; Aktas, Mehmet S.; Yildiz, Beytullah
    The paper addresses the limitations of traditional evaluation metrics for Question Answering (QA) systems that primarily focus on syntax and n-gram similarity. We propose a novel model-based evaluation metric, MQA-metric, and create a human-judgment-based dataset, squad-qametric and marco-qametric, to validate our approach. The research aims to solve several key problems: the objectivity in dataset labeling, the effectiveness of metrics when there is no syntax similarity, the impact of answer length on metric performance, and the influence of real answer quality on metric results. To tackle these challenges, we designed an interface for dataset labeling and conducted extensive experiments with human reviewers. Our analysis shows that the MQA-metric outperforms traditional metrics like BLEU, ROUGE and METEOR. Unlike existing metrics, MQA-metric leverages semantic comprehension through large language models (LLMs), enabling it to capture contextual nuances and synonymous expressions more effectively. This approach sets a standard for evaluating QA systems by prioritizing semantic accuracy over surface-level similarities. The proposed metric correlates better with human judgment, making it a more reliable tool for evaluating QA systems. Our contributions include the development of a robust evaluation workflow, creation of high-quality datasets, and an extensive comparison with existing evaluation methods. The results indicate that our model-based approach provides a significant improvement in assessing the quality of QA systems, which is crucial for their practical application and trustworthiness.
  • Other
    Citation - WoS: 0
    Etches of Life
    (Forum Literary Voice, 2024) Aras, Goksen
  • Article
    Citation - WoS: 0
    Citation - Scopus: 0
    Observations on Nist Sp 800-90b Entropy Estimators
    (Springer, 2025) Aslan, Melis; Doganaksoy, Ali; Saygi, Zulfukar; Turan, Meltem Sonmez; Sulak, Fatih
    Random numbers play a crucial role in cryptography since the security of cryptographic protocols relies on the assumption of the availability of uniformly distributed and unpredictable random numbers to generate secret keys, nonce, salt, etc. However, real-world random number generators sometimes fail and produce outputs with low entropy, leading to security vulnerabilities. The NIST Special Publication (SP) 800-90 series provides guidelines and recommendations for generating random numbers for cryptographic applications and describes 10 black-box entropy estimation methods. This paper evaluates the effectiveness and limitations of the SP 800-90 methods by exploring the accuracy of these estimators using simulated random numbers with known entropy, investigating the correlation between entropy estimates, and studying the impacts of deterministic transformations on the estimators.
  • Article
    Citation - WoS: 0
    Citation - Scopus: 0
    On Reliability of Consecutive k-out-of-n:G System Equipped With Protection Blocks
    (Taylor & Francis Ltd, 2025) Eryilmaz, Serkan
    The linear consecutive k-out-of-n:G system consists of n linearly ordered components such that the system works properly when there exists at least k consecutively working components. This paper is concerned with the reliability evaluation of the linear consecutive k-out-of-n: G system equipped with protection blocks. Protection blocks which have their failure rates are used to increase the system reliability. The closed-form expressions for the system reliability when $ 2k\geq n $ 2k >= n are obtained when the most critical components, i.e. the components that have the highest importance levels are involved by the protection blocks. Numerical examples are provided to illustrate the closed-form reliability equations.
  • Article
    Citation - WoS: 0
    Bacterial Profiling of Brined Grapevine Leaves Collected From Different Local Markets in Türkiye
    (Wiley-v C H verlag Gmbh, 2025) Ucak, Samet; Yegin, Zeynep; Yurt, Mediha Nur Zafer; Sudagidan, Mert; Altunbas, Osman; Ozalp, Veli Cengiz
    Microorganisms linked to the grapevine, Vitis vinifera, can impact crop quality, plant growth, and human and plant health. This study examined the bacterial community structures of brined grapevine leaves (n = 56) taken from seven distinct regions in T & uuml;rkiye using next-generation sequencing technology. Investigations were also conducted into the samples' chemical properties. Firmicutes was the dominant phylum, followed by Proteobacteria, Actinobacteria, and Bacteroidetes. Bacillaceae was the predominant family in the analyzed samples, followed by Clostridiaceae, Peptostreptococcaceae, and Enterobacteriaceae. Bacillus was the dominant genus, followed by Lysinibacillus and Clostridium sensu stricto. The samples exhibited differences in terms of pH, total acidity, and salt content. The pH values of the brined grapevine leaves ranged from 2.31 to 6.91, the acidity levels ranged from 0.09% to 1.80%, and the salt percentages ranged from 3.39% to 49.14%. This research provides pioneering information for bacterial community analysis of brined grapevine leaves.
  • Article
    Citation - WoS: 0
    Citation - Scopus: 0
    A Novel Deep Learning-Based Framework With Particle Swarm Optimisation for Intrusion Detection in Computer Networks
    (Public Library Science, 2025) Yilmaz, Abdullah Asim
    Intrusion detection plays a significant role in the provision of information security. The most critical element is the ability to precisely identify different types of intrusions into the network. However, the detection of intrusions poses a important challenge, as many new types of intrusion are now generated by cyber-attackers every day. A robust system is still elusive, despite the various strategies that have been proposed in recent years. Hence, a novel deep-learning-based architecture for detecting intrusions into a computer network is proposed in this paper. The aim is to construct a hybrid system that enhances the efficiency and accuracy of intrusion detection. The main contribution of our work is a novel deep learning-based hybrid architecture in which PSO is used for hyperparameter optimisation and three well-known pre-trained network models are combined in an optimised way. The suggested method involves six key stages: data gathering, pre-processing, deep neural network (DNN) architecture design, optimisation of hyperparameters, training, and evaluation of the trained DNN. To verify the superiority of the suggested method over alternative state-of-the-art schemes, it was evaluated on the KDDCUP'99, NSL-KDD and UNSW-NB15 datasets. Our empirical findings show that the proposed model successfully and correctly classifies different types of attacks with 82.44%, 90.42% and 93.55% accuracy values obtained on UNSW-B15, NSL-KDD and KDDCUP'99 datasets, respectively, and outperforms alternative schemes in the literature.
  • Article
    Citation - WoS: 0
    Citation - Scopus: 0
    Microfluidic Rapid Isolation and Electrochemical Detection of S. Pneumonia Via Aptamer-Decorated Surfaces
    (Elsevier, 2025) Babaie, Zahra; Kibar, Gunes; Yesilkaya, Hasan; Amrani, Yassine; Dogan, Soner; Tuna, Bilge G.; Cetin, Barbaros; Özalp, Veli Cengiz
    Background: S. pneumoniae is widely recognized as a leading cause of respiratory infections worldwide, often resulting in high mortality rates. However, the advent of microfluidic technologies has brought significant advancements, including the simplified, sensitive, cost-effective, and rapid approach to pneumococcal bacteremia detection. In this study, a microfluidic magnetic platform is presented for rapid isolation, and an electrode array is utilized for the electrochemical detection of S. pneumoniae. Aptamer-decorated surfaces were employed for both isolation and detection. For isolation, silica magnetic microparticles were synthesized and decorated with aptamer. Results: Isolation performance was assessed for phosphate-buffered saline (PBS) and blood samples for different concentrations of S. pneumoniae. Electrical impedance spectroscopy (EIS) with fabricated gold interdigitated electrodes (IDEs) decorated with aptamer was implemented for the detection of S. pneumoniae at different bacteria concentrations. The microfluidic platform performed bacteria isolation at comparable isolation efficiency with batch systems but at a much faster rate (isolation took about a minute, and the aptamer-decorated electrode array exhibited a limit of detection (LOD) at 962 CFU/mL and linear range between 104 and 107CFU/mL. Significance: Our method represents a significant advancement compared to previous reports. Our microfluidic platform can efficiently isolate 60 mu L of the bacteria sample within about one minute. The entire process takes about two minutes including the detection step. Furthermore, our method achieves a notable improvement in the detection limit for S. pneumoniae compared to conventional ELISA and magnetic microfluidics ELISA.
  • Article
    Citation - WoS: 0
    Citation - Scopus: 0
    The Relationship Between Concentric and Isometric Strength of Knee Flexor and Extensor Muscles and Postural Stability in Mild Stage Multiple Sclerosis Patients
    (Taylor & Francis Ltd, 2025) Yilmaz, Seval; Unluer, Nezehat Ozgul
    Background Multiple sclerosis (MS) affects muscle strength and postural stability. However, the relationship between concentric and isometric strength of knee flexors and extensors and postural stability in mild stage MS is not well known. The aim of the study was to examine the relationship between concentric and isometric strength of knee flexors and extensors and postural stability in mild stage MS patients. Materials and Methods The study included 21 mild-stage MS patients with an EDSS score of 4 or less and 21 healthy controls. The concentric and isometric strength of knee flexors and extensors was measured with the Biodex System 4 Dynamometer, and postural stability with the Biodex Balance System under eyes-open and eyes-closed conditions on a rigid surface. Results Mild-stage MS patients had reduced concentric strength of knee extensors and flexors and increased postural sway compared with healthy controls (p < 0.05). Isometric strength of knee extensors and flexors in mild stage MS patients were similar to healthy controls (p > 0.05). There was a moderate positive correlation between concentric strength of knee extensors and flexors and isometric strength of knee flexors and open-eye postural stability indexes in mild stage multiple sclerosis patients (p < 0.05). Conclusions While isometric strength of knee extensors and flexors was preserved, concentric strength of knee extensors and flexors was decreased, and postural stability was adversely affected in mild stage MS patients. The increase in the strength of the knee muscles was associated with an increase in their postural sway in mild stage MS patients.
  • Conference Object
    Citation - WoS: 0
    Association of Abdominal Stria With Pelvic Floor Dysfunction in Primigravid Pregnant Women
    (Springer London Ltd, 2023) Karakaya, G.; Sonmezer, E.; Dokmeci, F.; Seval, M. M.; Cetinkaya, S. E.; Varli, B.
  • Article
    Citation - WoS: 0
    The Effect of a Single Session Rubber Hand Illusion on Pressure Pain Is Not Long-Lasting
    (Wiley, 2025) Ceylan, Hatice; Acet, Nagihan; Gunendi, Zafer
    BackgroundRubber hand illusion (RHI) is an experience that causes changes in body perception and awareness as a result of the integration of simultaneous perceived visual and tactile stimuli. After synchronous brush strokes with rubber and real hands, the person perceives the rubber hand as their own. RHI is known to alter pain perception. In this study, it was aimed to evaluate the effects of RHI on pressure pain threshold and continuity of this effect.MethodsTwenty-three volunteers who developed RHI were included in our study and two conditions, illusion (synchronous) and control (asynchronous), were applied. The illusion condition was created by synchronous brush strokes, while the control condition was created by asynchronous brush application using different frequency and different finger areas in the same individuals. In both conditions, pressure pain threshold measurements with an algometer were performed at four times: baseline/1st measurement, during the brush stroke/2nd measurement, at the end of the brush stroke/3rd measurement and after the hand was removed from the environment/4th measurement.ResultsIt was shown that RHI increased the pressure-pain threshold (p = 0.004) in healthy volunteers. Asynchronous brush strokes arranged as a control trial significantly decreased the pressure pain threshold (p = 0.002).ConclusionsIt was found that the threshold values that change during the brush strokes return to the initial state after the brush strokes are terminated and the rubber hand is removed from the environment so that the effect of the illusion does not last for a long time with a single session application.
  • Conference Object
    Citation - WoS: 0
    Femicides in Turkey: Analysis of the Last Two Decades' Cases
    (Oxford Univ Press, 2022) Erbaydar, N. P.; Muharremoglu, Z. D.; Mutlu, D. A.
  • Conference Object
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  • Conference Object
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    A Cell Therapy Assisted Novel Microfluidic Device Promotes In Vitro Spermatogenesis in Neonatal Mice
    (Elsevier Science inc, 2022) Onen, Selin; Atik, Ali Can; Gizer, Merve; Kose, Sevil; Yaman, Onder; Kulah, Haluk; Korkusuz, Petek
  • Article
    Citation - WoS: 0
    The American Dream: Cultural and Social Downfall in John Steinbeck's of Mice and Men
    (Literary Voice, 2022) Aras, Goksen; Takva, Serdar
    As known, throughout history, most societies have experienced hard times that have made life difficult to bear. Among these hard times are political, social and economic conditions which shape the ways human beings perceive the world and lead their lives. The Great Depression, that ravaged American society in the 1929s, is one of the most catastrophic economic events in the history of America and it is considered to be a calamity resulting in unemployed, desperate and even homeless people. John Steinbeck, being one of the foremost representatives of American writers, handles the devastating effects of the Great Depression and how it affected numerous people from different parts of the community. In this period, from women to the black, from the old to the disabled. most people wanted to lead a life based on humanly standards but what they expected turned into a frustration paving the way for the impossibility of the American dream and thus cultural and social downfall of such people no matter how hard they try to achieve their goals. Steinbeck's novel titled Of Mice and Men in this context is a touching representation of frustration, hopelessness, despair to have a place to live in, and a portrayal of unattainable happiness and the impossible American dream. This paper explores the futile efforts to realize the American dream and thus unhappiness and failure from Steinbeck's point of view and it presents the reflections of such a concept through the fictionalized characters in the novel.
  • Article
    Citation - WoS: 1
    Perceived Health Outcomes of Recreation Scale: Measurement Invariance Over Gender
    (Iranian Scientific Society Medical Entomology, 2022) Kose, Elif; Yerlisu-Lapa, Tennur; Uzun, Nezaket Bilge; Kaas, Evren Tercan; Serdar, Emrah; Aras, Goksen
    Background: Research handling structural differences among groups presume that the measurement tool works similarly among the groups and the results of measurements provide similar psychometric properties. Therefore, the aim of the study is to provide evidence for measurement invariance of the construct validity Perceived Health Outcomes of Recreation Scale (PHORS).Methods: The research sample consisted of a total of 1984 adults who exercise, including 864 women and 1120 men during 2021-2022 in Antalya City, Turkey. The MI of the PHORS was tested by multigroup con-firmatory factor analyses, which test the invariance of the covariance structures within the scope of structural equation modelling. Invariance tests were gradually conducted for the implicit variables in the model, CFI (comparative fit index criteria) and AIC (Akaike information criterion) were inquired between structural invari-ance, where no restriction was applied on the analyses and the other invariance tests (metric invariance, scalar invariance and string invariance respectively) where more restraints are applied.Results: The study yielded evidence showing that the measurement model defined for the factor structure of the scale provided measurement invariance by gender. increment CFI values were <= 0.010 in all subscales for metric and scalar invariance.Conclusion: The items of PHORS represented the same psychological structure, different groups responded to the items in the same way, the constant values in regression equations generated for the items in regression equations were equal/invariable between the groups.
  • Article
    Citation - WoS: 0
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    Effects of Carbon Dioxide Pneumoperitoneum on Renal Function in Obstructive Jaundice: an Experimental Study in a Rat Model
    (Asoc Regional Dialisis Trasplantes Renales, 2023) Gulen, Merter; Sare, Mustafa; Kozan, Ramazan; Yuksel, Seher; Deger, Serpil Muge; Senes, Mehmet; Cayci, Ayse Banu
    Introduction: Both pneumoperitoneum (PNP) and obstructive jaundice (OJ) are known to lead to acute kidney injury (AKI) potentially, but the combined effect has not been investigated. Aim: This study aimed to investigate the effects of PNP on renal functions in a rat model of OJ. Methods: We divided forty-eight rats into eight groups of six rats. Group 1 was the control (sham-operated) group; Groups 2, 3, and 4 were induced 5, 10, and 15 mmHg of CO2 PNP, respectively (Groups 1-4: "non-OJ Groups"); Group 5 was the OJ group; and Groups 6, 7 and 8 were OJ groups that were induced with 5, 10, and 15 mmHg CO2 PNP was respectively (Groups 5-8: "OJ Groups"). The common bile duct was ligated and divided into OJ Groups. After 48 hours, a 5-10-15 mmHg PNP was induced by mini-laparotomy with a Veress needle in Groups 6, 7, and 8, maintained for 60 minutes. Results: There were no statistically significant differences between groups regarding blood urea Nitrogen and Creatinin levels (p> 0.05). Neutrophil gelatinase-associated lipocalin (NGAL) values were significantly higher in OJ Groups than in non-OJ Groups (p< 0.05). Serum Cystatin-C values were significantly higher in OJ Groups with 10 and 15 mmHg PNP than in nonOJ Groups (p< 0.05). Conclusion: In the early stage of AKI, NGAL and Cystatin-C levels might be higher, while standard renal function tests were normal. Our findings highlight the apparent unfavorable effect of OJ with PNP on renal functions and early recognition of AKI with the measurement of NGAL and Cystatin-C in these conditions.