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Wage effects of educational mismatch in public and private sectors: evidence from Türkiye
No full textPurpose: Significant changes have been observed in Türkiye labor market over the last two decades, driven by the substantial increase in the number of universities and students and by factors such as economic crises and unemployment. This phenomenon has also affected the number of overeducated (undereducated) wage earners in the labor market. In this study, we first consider compulsory education policy to calculate the educational mismatch. Our aim is to analyze the wage returns of overeducated (undereducated) workers employed in the public and private sectors. The pooled data from the TurkStat Household Labour Force Survey for 2021 and 2022 are used. Design/methodology/approach: Unconditional quantile regression (UQR) was introduced by Firpo et al. (2009). The UQR method has become very popular and is used in several areas, such as labor economics, health economics and public policy, to examine income inequality, discrimination by gender and discrimination by race and others (Agyire et al., 2018; Gaeta et al., 2023). Firpo et al. (2009) used the recentered influence function (RIF) to estimate the outcome equation (wage equation in our case) to obtain UQR estimates. The RIF regresses the influence function (IF) which is developed by Hampel (1974) (Rios-Avila, 2020). Findings: We find that overeducated workers in the Turkish labor market received a wage penalty relative to required educated workers. The returns to years of required education are positive, which means that the returns to each year of required education have higher wages than each year of their overeducated counterparts employed in the same occupation. In the private sector, the effect of the increase in one year of education on wages in the lower percentile is lower than in the public sector for both overeducation, undereducation and required education. Originality/value: An important contribution of our study is the inclusion of the compulsory education policy in the calculation of the educational mismatch in Türkiye. The study uses data from the Household Labour Force Survey (HLFS) covering the period 2021–2022. Previous studies on the wage effects of educational mismatch in Türkiye have typically addressed this issue in the context of conditional wage distribution. However, wages can vary significantly at different points in the distribution. An important advantage of the UQR is its ability to provide comparable coefficient estimates across the wage distribution
Seismic behavior of cold-formed steel framed multi-panel and two-story shear walls
No full textThis paper presents an experimental investigation on the seismic behavior of cold-formed steel (CFS) shear wall systems. Two sets of cyclic lateral loading tests were conducted on OSB sheathed CFS shear wall specimens. The first part of the study deals with walls constructed by connecting multiple individual wall panels with different connection methods. Focus of the second part is the lateral load response of two-story shear walls with different framing details between wall panels in neighboring floors. In both parts, the behavior of wall panels was examined with combinations of one side sheathing and a coarse fastener layout, as well as double-side sheathing and a dense fastener layout. For the multi-panel shear walls, eight full-scale specimens were tested, featuring varying configurations of CFS framing and OSB sheathing. The experiments indicate that the use of different connection details between individual wall segments does not cause any appreciable difference in wall response. Significant excessive base slip was observed in longer walls with double-side sheathing due to increased shear force demand at the base, highlighting the importance of adequate fastener layout. In the investigation of two-story shear walls, eight specimens were tested. Platform and ledger framing details were explored, each with different methods of connecting wall panels between floors. The results demonstrated the influence of framing detail on the overall behavior and failure mechanisms of the shear walls. Notably, the presence of additional OSB sheathing panels between floors enhanced the load capacity and stiffness of the specimens, mitigating damage to CFS members within the connection region. Based on the experimental findings, practical recommendations were presented for multi-panel walls and interaction between wall panels and floor support system in multi-story CFS construction
Understanding Teacher Resistance to Organizational Change from the Perspectives of EFL Instructors
No full textComparative Aerodynamic Analysis and Parallel Performance of 2D CFD Simulations of a VAWT Using Sliding Mesh Interface Method
No full textWith rapid advancements in computer hardware and numerical modeling methods, Computational Fluid Dynamics (CFD) has gained prominence in simulating complex flows. As parallel computation becomes an industry standard, the computational efficiency of simulations has become critical. The flow around a Vertical Axis Wind Turbine (VAWT), characterized by complex dynamics and challenging rotating geometry, serves as an intriguing case for CFD studies. This study employs the open-source CFD solvers SU2 and OpenFOAM to simulate the incompressible, unsteady, and turbulent flow around an H-type Darrieus VAWT in two dimensions. Spatial and temporal discretization parameters are examined to balance computational cost and accuracy, revealing notable effects on power predictions. Simulations conducted under identical conditions allow for a comparison of the predictions and parallel performances of SU2 and OpenFOAM across three distinct tip speed ratios (TSRs). The findings show that discretization parameters behave differently at various TSRs. While power predictions from SU2 and OpenFOAM generally align with experimental data and with each other, discrepancies arise at lower TSRs, with thrust predictions showing better consistency. Although OpenFOAM provides a faster solution across all parallel configurations, SU2 demonstrates superior parallel scalability, achieving higher speedup and efficiency
A framework for assessing the circular economy potential in the water and agriculture sectors in Türkiye through the water-energy-food-ecosystem nexus
No full textThe growing need for agricultural production and the consequences of climate change necessitate new paradigms for sustainable resource management such as the Water-Energy-Food-Ecosystem (WEFE) nexus and the circular economy approach. The WEFE nexus promotes a holistic perspective to improve resource management and economic outcomes by emphasizing the interconnectivity of its components. The circular economy framework complements the WEFE Nexus by promoting the efficient use and reuse of resources across its interconnected components. This study proposes an integrated framework for preliminary assessments of water and agriculture sectoral potentials in water reuse and bioenergy production at a macro scale. This framework includes priority assessments using multidimensional criteria through the developed Circular Agriculture Priority Assessment (CAPA) index, which provide actionable insights targeted policies, strategic investments, and research to provide water, food, energy security and maintaining of ecosystem health in Türkiye. The results indicate that Türkiye's annual resources include 22.5 million tons of crop residue, 93.8 million tons of animal manure, and 2594 hm3 of urban wastewater, which could meet 10 % of agricultural water needs through reuse and produce 12,908,772 MWh of bioenergy, covering 4.16 % of residential electricity demand. However, only 14.6 % of this energy potential is currently exploited. The CAPA index highlights certain provinces for targeted policies, strategic investments, and research initiatives. By providing a multidimensional evaluation of circular agriculture strategies within the WEFE nexus framework, this research contributes to advancing sustainable resource security and improving decision-making in agricultural production systems
A Novel Design Technique for Ultrawideband Shared Aperture Connected Dipole Arrays
No full textThis paper presents comprehensive circuit models for the design and analysis of ultrawideband shared aperture antenna arrays. A novel semi-analytical approach is developed by modifying the previous equivalent circuit model to enable the calculation of the electromagnetic (EM) transparency of dipole array unit cells. Based on the EM transmission characteristics of the low-band dipole, an accurate circuit-based method is introduced for calculating the input impedance of a shared aperture antenna. Notably, the only full-wave simulation required is that of the standalone high-band antenna. To demonstrate the effectiveness of the proposed technique, two distinct shared aperture dipole array designs are presented. In both cases, the high-band antennas are implemented using tightly coupled dipole array (TCDA) elements. The first design achieves a 26.2:1 impedance bandwidth with active VSWR < 2.3 and a low-profile height of (Formula presented.), where (Formula presented.) denotes the free-space wavelength at the lowest operating frequency. The second design achieves a 33.3:1 bandwidth with active VSWR < 3 and a profile height of just (Formula presented.). The average total efficiencies of the two designs are 0.86 and 0.85, respectively
Certain Completeness Properties and Mappings
No full textWe prove, among the others, that the directed completeness is preserved under perfect mappings. We introduce some new notions such as nearly directed completeness, -directed completeness and directed completeness of a family. We prove that nearly directed completeness is preserved under continuous, open images and preimages with compact fibers, and consequently, we obtain that a topological group is nearly directed complete if and only if the quotient to a compact subgroup of of is nearly directed complete. We also give an upper bound for domains which improves given one in [7] and this is an answer to Question 11.10 in [3]
Solution of discrete time–cost trade-off problem with adaptive search domain
No full textPurpose: Exact solution of time–cost trade-off problem (TCTP) by the state-of-the-art meta-heuristic algorithms can be obtained for small- and medium-scale problems, while satisfactory results cannot be obtained for large construction projects. In this study, a hybrid heuristic meta-heuristic algorithm that adapts the search domain is developed to solve the large-scale discrete TCTP more efficiently. Design/methodology/approach: Minimum cost slope–based heuristic network analysis algorithm (NAA), which eliminates the unfeasible search domain, is embedded into differential evolution meta-heuristic algorithm. Heuristic NAA narrows the search domain at the initial phase of the optimization. Moreover, activities with float durations higher than the predetermined threshold value are eliminated and then the meta-heuristic algorithm starts and searches the global optimum through the narrowed search space. However, narrowing the search space may increase the probability of obtaining a local optimum. Therefore, adaptive search domain approach is employed to make reintroduction of the eliminated activities to the design variable set possible, which reduces the possibility of converging into local minima. Findings: The developed algorithm is compared with plain meta-heuristic algorithm with two separate analyses. In the first analysis, both algorithms have the same computational demand, and in the latter analysis, the meta-heuristic algorithm has fivefold computational demand. The tests on case study problems reveal that the developed algorithm presents lower total project costs according to the dependent t-test for paired samples with α = 0.0005. Research limitations/implications: In this study, TCTP is solved without considering quality or restrictions on the resources. Originality/value: The proposed method enables to adapt the number of parameters, that is, the search domain and provides the opportunity of obtaining significant improvements on the meta-heuristic algorithms for other engineering optimization problems, which is the theoretical contribution of this study. The proposed approach reduces the total construction cost of the large-scale projects, which can be the practical benefit of this study
Transcutaneous Vagus Nerve Stimulation Effects on Flavor-Evoked Electroencephalogram and Eye-Blink Rate
No full textIntroduction: Chemosensory food signals are carried by the vagus nerve (VN) from the gut to the brain and these signals contribute to communicating fullness and caloric value of the consumed food in regulatory and reward-related contexts. Here, we aimed to explore whether neural responses to flavor can be modulated through noninvasive VN stimulation, which can be done transcutaneously (transcutaneous vagus nerve stimulation [tVNS]) on the outer ear via the auricular branch of VN. The ideal stimulation location on the outer ear for tVNS is not agreed on but two candidate locations are cymba conchae and tragus. Methods: In this study, we explore the optimal stimulation location for tVNS (cymba conchae, tragus, and cymba conchae and tragus) and timing of tVNS relative to chocolate milk presentation (during, after) in a within-participants design (15 participants). We examined various measures of efficacy; event-related potential from electroencephalogram, eye-blink rate, perceptual and hedonic aspects of flavor, swallowing behavior, and consumption behavior. Results: We observed no effect of stimulation location on any of the dependent variables. Unexpectedly, we observed a large effect of food consumption on spontaneous eye-blink rate. Conclusion: In conclusion, overall we did not observe a clear optimal ear location for tVNS-induced modulation of neurophysiological, perceptual, and behavioral variables. Future studies may confirm whether spontaneous eye-blink rate can be a sensitive proxy for food reward-related phasic dopamine shifts
Geographical Information Systems-Based Assessment of Evacuation Accessibility to Special Needs Shelters Comparing Storm Surge Impacts of Hurricane Irma (2017) and Ian (2022)
No full textResearch on hurricane impacts in Florida's coastal regions has been extensive, yet there remains a gap in comparing the effects and potential damage of different hurricanes within the same geographical area. Additionally, there is a need for reliable discussions on how variations in storm surges during these events influence evacuation accessibility to hurricane shelters. This is especially significant for rural areas with a vast number of aging populations, whose evacuation may require extra attention due to their special needs (i.e., access and functional needs). Therefore, this study aims to address this gap by conducting a comparative assessment of storm surge impacts on the evacuation accessibility of southwest Florida communities (e.g., Lee and Collier Counties) affected by two significant hurricanes: Irma in 2017 and Ian in 2022. Utilizing the floating catchment area method and examining Replica's OD Matrix data with Geographical Information Systems (GISs)-based technical tools, this research seeks to provide insights into the effectiveness of evacuation plans and identify areas that need enhancements for special needs sheltering. By highlighting the differential impacts of storm surges on evacuation accessibility between these two hurricanes, this assessment contributes to refining disaster risk reduction strategies and has the potential to inform decision-making processes for mitigating the impacts of future coastal hazards