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Article Citation - WoS: 4Citation - Scopus: 4An Integrated Economy-Demography Model Reframed in a System Dynamics Setting(Wiley, 2019) Dural-Selcuk, Gozdem; Tunc, Huseyin; Tarim, S. ArmaganIn recent history, there has been an increasing concern about population aging and the associated increased economic burden in terms of high health-care expenses and pension payments. The need for decision support tools that can explore population dynamics has become a prominent issue. This study presents a comprehensive framework where one can scrutinize the key demographic drives of fertility (Total Fertility Rate/Age-Specific Fertility Rate) over macroeconomic indicators (technology, education, human capital) under exogenous mortality. The integrated model in this article is developed based on a reformulation of the unified growth theory. In the reformulated model, namely the "economy-demography model," the population age/sex structure is preserved, age-specific mortality is included, and fertility is measured in conventional demographic terms. The model is then presented in system dynamics framework, and its practical use is showcased with data obtained from the Turkish Statistical Institute. Copyright (c) 2020 System Dynamics SocietyArticle Validating the Turkish Adaptation of the Fear of Being Single Scale(Wiley, 2024) Kirimer-Aydinli, Fulya; Kucukkomurler, SanemPeople may experience anxiety regarding their future romantic relationship status. Fear of being single (FOBS) is a potential cause of this anxiety, characterized by distress about the idea of being single and assessed through the FOBS Scale. In the current study, the FOBS Scale was adapted into Turkish. The study included 349 individuals aged 28-55 years (M = 23.63 years, SD = 6.45 years). The reliability and validity of the measure and the associations with particular variables were investigated for the first time in the cultural context of Turkey. The confirmatory factor analysis revealed an acceptable model fit for the single-factor structure. Measurement invariance of the scale across relationship status was supported at configural and metric levels, but not at the scalar level. The convergent and divergent validity analyses indicated that FOBS is distinct from generalized anxiety, attachment anxiety, and the personality trait of neuroticism. FOBS was found to be related to the need to belong but not to the inclusion of close others into the self. It has been determined that FOBS is a distinctive phenomenon, and the Turkish version of the FOBS Scale is a valid and reliable tool for assessing FOBS in Turkey.Article Citation - WoS: 3Citation - Scopus: 4Nanoremediation of Toxic Dyes Using a Bacterial Consortium Immobilized on Cellulose Acetate Nanofiber Mats(Wiley, 2024) Erkoc, Esra; Tuzun, Imre; Korkmaz, Filiz; San Keskin, Nalan Oya; Kocberber Kilic, NurStenotrophomonas maltophilia and Ochrobactrum sp. demonstrated the highest rates of dye bioremediation. The trials were performed at pH 8, which resulted in the highest bioremediation rate of 64.6% in media containing 21.2 mg L-1 dye. As the dye concentration increased, the pollutant removal decreased, with the maximum bioremoval rate of 70.3%. The removal capacity was increased with an increase in biomass concentration; the highest yield of 91.3% was obtained in media containing 14.2 mg L-1 dye and 12% (v/v) biomass. In nanoremediation studies, the bacterial consortium was immobilized on cellulose acetate nanofiber mats (CA-NFM). Scanning electron microscopic micrographs showed that bead-free nanofiber mats were effective in immobilizing bacterial cells. Moreover, nanofiber structures were capable of supporting exopolysaccharides formation, as confirmed by Fourier transform & imath;nfrared spectroscopy. The bacterial consortium immobilized on CA-NFM showed a maximum bioremoval rate of 56.5%. Reusability tests demonstrated that the consortium immobilized CA-NFM could be used at least five times. Furthermore, after leaving the mat for 1 month at 4 degrees C, it was still usable, and the removal efficiency was found to be 45.4%. Based on our findings, bacteria immobilized on CA-NFM have the potential to be used as highly effective and versatile nanobiotechnological biological sorbents in the treatment of wastewater containing dyes.Article Citation - WoS: 30Citation - Scopus: 44Text Classification Using Improved Bidirectional Transformer(Wiley, 2022) Tezgider, Murat; Yıldız, Beytullah; Yildiz, Beytullah; Aydin, Galip; Yıldız, BeytullahText data have an important place in our daily life. A huge amount of text data is generated everyday. As a result, automation becomes necessary to handle these large text data. Recently, we are witnessing important developments with the adaptation of new approaches in text processing. Attention mechanisms and transformers are emerging as methods with significant potential for text processing. In this study, we introduced a bidirectional transformer (BiTransformer) constructed using two transformer encoder blocks that utilize bidirectional position encoding to take into account the forward and backward position information of text data. We also created models to evaluate the contribution of attention mechanisms to the classification process. Four models, including long short term memory, attention, transformer, and BiTransformer, were used to conduct experiments on a large Turkish text dataset consisting of 30 categories. The effect of using pretrained embedding on models was also investigated. Experimental results show that the classification models using transformer and attention give promising results compared with classical deep learning models. We observed that the BiTransformer we proposed showed superior performance in text classification.Article Citation - WoS: 3Citation - Scopus: 5Particle Swarm Optimization of the Spectral and Energy Efficiency of an Scma-Based Heterogeneous Cellular Network(Wiley, 2022) Noma-Osaghae, Etinosa; Misra, Sanjay; Ahuja, Ravin; Koyuncu, MuratBackground The effect of stochastic small base station (SBS) deployment on the energy efficiency (EE) and spectral efficiency (SE) of sparse code multiple access (SCMA)-based heterogeneous cellular networks (HCNs) is still mostly unknown. Aim This research study seeks to provide insight into the interaction between SE and EE in SBS sleep-mode enabled SCMA-based HCNs. Methodology A model that characterizes the energy-spectral-efficiency (ESE) of a two-tier SBS sleep-mode enabled SCMA-based HCN was derived. A multiobjective optimization problem was formulated to maximize the SE and EE of the SCMA-based HCN simultaneously. The multiobjective optimization problem was solved using a proposed weighted sum modified particle swarm optimization algorithm (PSO). A comparison was made between the performance of the proposed weighted sum modified PSO algorithm and the genetic algorithm (GA) and the case where the SCMA-based HCN is unoptimized. Results The Pareto-optimal front generated showed a simultaneous maximization of the SE and EE of the SCMA-based HCN at high traffic levels and a convex front that allows network operators to select the SE-EE tradeoff at low traffic levels flexibly. The proposed PSO algorithm offers a higher SBS density, and a higher SBS transmit power at high traffic levels than at low traffic levels. The unoptimized SCMA-based HCN achieves an 80% lower SE and a 51% lower EE than the proposed PSO optimized SCMA-based HCN. The optimum SE and EE achieved by the SCMA-based HCN using the proposed PSO algorithm or the GA are comparable, but the proposed PSO uses a 51.85% lower SBS density and a 35.96% lower SBS transmit power to achieve the optimal SE and EE at moderate traffic levels. Conclusion In sleep-mode enabled SCMA-based HCNs, network engineers have to decide the balance of SBS density and SBS transmit power that helps achieve the desired SE and EE.Article Citation - WoS: 17Citation - Scopus: 26Toward Ontology-Based Risk Management Framework for Software Projects: an Empirical Study(Wiley, 2020) Abioye, Temitope Elizabeth; Arogundade, Oluwasefunmi Tale; Misra, Sanjay; Akinwale, Adio T.; Adeniran, Olusola JohnSoftware risk management is a proactive decision-making practice with processes, methods, and tools for managing risks in a software project. Many existing techniques for software project risk management are textual documentation with varying perspectives that are nonreusable and cannot be shared. In this paper, a life-cycle approach to ontology-based risk management framework for software projects is presented. A dataset from literature, domain experts, and practitioners is used. The identified risks are refined by 19 software experts; risks are conceptualized, modeled, and developed using Protege. The risks are qualitatively analyzed and prioritized, and aversion methods are provided. The framework is adopted in real-life software projects. Precision recall and F-measure metrics are used to validate the performance of the extraction tool while performance and perception evaluation are carried out using the performance appraisal form and technology acceptance model, respectively. Mean scores from performance and perception evaluation are compared with evaluation concept scale. Results showed that cost is reduced, high-quality projects are delivered on time, and software developers found this framework a potent tool needed for their day-to-day activities in software development.Article Citation - WoS: 2Citation - Scopus: 2Assessment of Anticancer Effects of Aloe Vera on 3D Liver Tumor Spheroids in a Microfluidic Platform(Wiley, 2025) Tevlek, Atakan; Kibar, Gunes; Cetin, BarbarosThe search for effective anticancer therapies has increasingly focused on natural compounds like Aloe vera, renowned for its therapeutic properties. This study investigates the anticancer properties of Aloe vera on 3D liver tumor spheroids via a PDMS-based microfluidic device, providing a more physiologically realistic model compared to traditional 2D cultures. HepG2 cells were cultivated to generate 3D spheroids on-chip, thereafter subjected to different concentrations of Aloe vera and the chemotherapeutic drug Doxorubicin to evaluate cytotoxic effects. The microfluidic system, validated by COMSOL simulations, facilitated continuous perfusion and real-time assessment of cell viability over a duration of 10 days. The results indicated that Aloe vera markedly diminished cell viability by triggering apoptosis at concentrations over 12.5 mg/mL. IC50 values were determined at 72 h: 25 +/- 0.10 mg/mL for Aloe vera and 5.47 +/- 0.03 mu g/mL for Doxorubicin in 2D cultures, but in 3D cultures, the IC50 values were 31.25 +/- 0.14 mg/mL for Aloe vera and 8.33 +/- 0.05 mu g/mL for Doxorubicin. This study underscores the promise of Aloe vera as a natural anticancer agent and illustrates the efficacy of microfluidic platforms for enhanced drug screening and customized medicine applications.Article Citation - WoS: 4Citation - Scopus: 3Boundary Value Problems on Half-Line for Second-Order Nonlinear Impulsive Differential Equations(Wiley, 2018) Akgol, S. D.; Zafer, A.We obtain sufficient conditions for existence and uniqueness of solutions of boundary value problems on half-line for a class of second-order nonlinear impulsive differential equations. Our technique is different than the traditional ones, as it is based on asymptotic integration method involving principal and nonprincipal solutions. Examples are provided to illustrate the relevance of the results.Article Citation - WoS: 6Citation - Scopus: 4Is real per capita state personal income stationary? New nonlinear, asymmetric panel-data evidence(Wiley, 2020) Emirmahmutoglu, Furkan; Gupta, Rangan; Miller, Stephen M.; Omay, TolgaThis paper re-examines the stochastic properties of U.S. state real per capita personal income, using new panel unit-root procedures. The new developments incorporate non-linearity, asymmetry, and cross-sectional correlation within panel-data estimation. Including nonlinearity and asymmetry finds that 43 states exhibit stationary real per capita personal income whereas including only nonlinearity produces 42 states that exhibit stationarity. Stated differently, we find that two states exhibit nonstationary real per capita personal income when considering nonlinearity, asymmetry, and cross-sectional dependence.Conference Object
