WoS İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8653

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Women’s Labor Force Participation After Disasters: The Case of Nurdağı, Türkiye, Following Kahramanmaraş Earthquakes
(Wiley, 2026) Orhan, Ezgi; Wein, Anne M.; Kroll, Cynthia A.
Economic functionality is essential for the recovery of cities and communities following disasters. A crucial factor in reducing business disruptions and guaranteeing their continuity is the capacity of employees to resume work. Facilitating the reintegration of employees into the workforce can expedite their post-disaster recovery process and assist the impacted communities in their recuperation. Nevertheless, when women encounter numerous challenges in returning to the workforce, the share of women's employment declines. This study aims to elucidate the challenges and expectations of women living in the region directly impacted by the February 6, 2023, Kahramanmaraş earthquakes regarding their participation in the post-disaster job market. Nurdağı town in Gaziantep province, where the impacts of the February 6th earthquakes are evident, was selected as the case study. One year later, a survey was administered to 375 women living in a Nurdağı container city. The study explores earthquake damages and losses to their homes and workplaces, their migration status post-disaster, the challenges faced in labor market participation, and their expectations for employment. The responses clarify specific barriers to women's labor force participation in the first year following the earthquakes and the type of programs that could help overcome the difficulties faced. While state-sponsored temporary work programs facilitate women's employment in the short run, these jobs may not align with skills and prior work experience and do not address the longer-term needs for women seeking stable, permanent income-generating positions. Amid extensive destruction, the establishment of a secure living environment had become the most basic need, while gender-specific supports are also important in restoring women's labor force participation, including psychological treatment options, programs to assist with the care of children and other dependents, and vocational development. The study highlights considerations when providing support for both employees and recovering businesses after a disaster.
Vessel Segmentation in MRI Using a Variational Image Subtraction Approach
(Tubitak Scientific & Technological Research Council Turkey, 2014) Nar, Fatih; Saran, Ayse Nurdan; Saran, Murat
Vessel segmentation is important for many clinical applications, such as the diagnosis of vascular diseases, the planning of surgery, or the monitoring of the progress of disease. Although various approaches have been proposed to segment vessel structures from 3-dimensional medical images, to the best of our knowledge, there has been no known technique that uses magnetic resonance imaging (MRI) as prior information within the vessel segmentation of magnetic resonance angiography (MRA) or magnetic resonance venography (MRV) images. In this study, we propose a novel method that uses MRI images as an atlas, assuming that the patient has an MRI image in addition to MRA/MRV images. The proposed approach intends to increase vessel segmentation accuracy by using the available MRI image as prior information. We use a rigid mutual information registration of the MRA/MRV to the MRI, which provides subvoxel accurate multimodal image registration. On the other hand, vessel segmentation methods tend to mostly suffer from imaging artifacts, such as Rician noise, radio frequency (RF) inhomogeneity, or partial volume effects that are generated by imaging devices. Therefore, this proposed method aims to extract all of the vascular structures from MRA/MRI or MRV/MRI pairs at the same time, while minimizing the combined effects of noise and RF inhomogeneity. Our method is validated both quantitatively and visually using BrainWeb phantom images and clinical MRI, MRA, and MRV images. Comparison and observer studies are also realized using the BrainWeb database and clinical images. The computation time is markedly reduced by developing a parallel implementation using the Nvidia compute unified device architecture and OpenMP frameworks in order to allow the use of the method in clinical settings.
The Lebesgue Constants on Projective Spaces
(Tubitak Scientific & Technological Research Council Turkey, 2021) Kushpel, Alexander
We give the solution of a classical problem of Approximation Theory on sharp asymptotic of the Lebesgue constants or norms of the Fourier-Laplace projections on the real projective spaces P-d (R). In particular, these results extend sharp asymptotic found by Fejer [2] in the case of S-1 in 1910 and by Gronwall [4] in 1914 in the case of S-2. The case of spheres, S-d, complex and quaternionic projective spaces, P-d(C), P-d(H) and the Cayley elliptic plane P-16 (Cay) was considered by Kushpel [8].
Sustainable Development Solutions Network (SDSN) Reports Between 2018 and 2023: Malmquist Index Analysis for the Performance of OECD Countries
(Wiley, 2026) Kalemci, R. Arzu; Unsal, Mehmet Guray; Alp, Ihsan; Celik, Busra Agan; Dalkilic, Altay Ogulcan
In 2015, the United Nations (UN) adopted the 17 Sustainable Development Goals (SDGs), calling for urgent action to end poverty, reduce inequality, and secure a sustainable future. Within this global agenda, the commitment of the Organization for Economic Co-operation and Development (OECD) is particularly significant given its institutional capacity and international influence. This study examines Sustainable Development Solutions Network (SDSN) reports for 2018-2023 using the Malmquist Productivity Index (MPI) as an alternative performance measurement tool. The MPI allows assessment of annual changes in total factor productivity and efficiency differences across OECD members. Rather than directly measuring absolute progress toward the SDGs, the analysis evaluates relative efficiency dynamics among countries in transforming sustainability-related indicators over time. The results provide comparative insights into how OECD countries improve or deteriorate in their relative sustainability performance within the observed period. The results show that OECD countries display uneven progress, with some improving while others stagnate or decline, and reveal persistent disparities in efficiency and productivity. By providing a dynamic and comparative evaluation, the study contributes to quantitative SDG monitoring and offers insights for policymakers seeking to enhance sustainable development strategies.
String Stable Cooperative Adaptive Cruise Control under Actuator Saturation
(Pamukkale Univ, 2016) Schmidt, Klaus Werner; Cankaya, Erkam; Bingol, Hilal
Cooperative adaptive cruise control (CACC) enables safe vehicle following in dense traffic based on distance measurements and communicated data via vehicle-to-vehicle communication. Existing CACC designs achieve the essential property of string stability but are limited to linear vehicle models. In this paper, we show that string stability is preserved when using a nonlinear vehicle model if the input signal of the leader vehicle does not saturate.
Simheuristic Framework for Optimizing Urban Mobility at Signalized Roundabouts
(DAAAM International Vienna, 2026) Gokce, M. A.; Qadri, S. S. S. M.; Oner, E.
Managing high traffic volumes and traffic congestion at signalized intersections remains a critical urban challenge. Appropriate traffic signal timing (TST) and phase sequencing are essential for ensuring smooth traffic flow. This study presents a microscopic simulation-based heuristic optimization (Simheuristic) framework using the Genetic Algorithm (GA) for optimizing the TST of Four-Legged Two-stops Signalized Roundabouts (FLTSR). The framework is tested using the actual traffic flow through a microscopic simulation model developed in Simulation for Urban Mobility (SUMO). Within this framework, the integrated GA searches for the green TSTs to minimize vehicular queue lengths, while SUMO is used to evaluate those timings. Additionally, four different phase sequence settings are evaluated to find the efficient configuration. The proposed approach is benchmarked against Webster's method and the existing TST plan. In the best-case scenario, the proposed framework improves vehicular flow by mitigating the average time loss, average waiting time, and the average number of vehicles in a queue at the FLTSR up to 35.83 %, 51.91 %, and 50.97 %, respectively, compared to the current setting. (Received in November 2025, accepted in January 2026. This paper was with the authors 1 month for 1 revision.)
Singular Dirac Systems in the Sobolev Space
(Tubitak Scientific & Technological Research Council Turkey, 2017) Ugurlu, Ekin
In this paper we construct Weyl's theory for the singular left-definite Dirac systems. In particular, we prove that there exists at least one solution of the system of equations that lies in the Sobolev space. Moreover, we describe the behavior of the solution belonging to the Sobolev space around the singular point.
Signal-to-Noise Ratio Reduction in Non-Kolmogorov Jet Engine Exhaust Turbulence
(IOP Publishing Ltd, 2026) Baykal, Yahya
In a medium experiencing non-Kolmogorov jet engine exhaust turbulence, signal-to-noise ratio (SNR) is evaluated. SNR is naturally degraded due to the presence of turbulence. The reduction in the SNR in non-Kolmogorov jet engine exhaust turbulence is calculated and presented with respect to the power law for various wireless optical communication link and turbulence parameters. The reduction in SNR is referenced to the SNR achieved in the link when there is no turbulence. SNR, being an important entity in determining the link performance, knowledge about the reduction in SNR will help the designers of wireless optical communication links, especially installed in airport environments where jet engine exhaust turbulence mostly occurs.
Revealing Fractional Effects in an Asymmetric Two-Dimensional Oscillator through Variational Mechanics
(SAGE Publications Ltd, 2026) Baleanu, Dumitru; Defterli, Ozlem; Asad, Jihad; Jajarmi, Amin; AlShaikh Mohammad, Noorhan F.
The present study is an application of a generalized Lagrangian-Hamiltonian approach to the analysis of an asymmetric two-dimensional harmonic oscillator with the use of the Caputo fractional derivative. Fractional Euler-Lagrange and Hamiltonian equations were systematically developed and then solved numerically using a predictor-corrector version of the Adams-Bashforth-Moulton method. The results show that decreasing the value of the fractional order (alpha) generates a form of memory-based damping within the system that transforms the classical closed orbits of phase space into spiral inward trajectories and causes the total energy of the system to decrease according to a power law, regardless of whether there are any dissipative forces in the system. It was demonstrated that both the degree of coupling and the degree of asymmetry can cause the system to lose energy at different rates and to have different amounts of attenuation in each direction. It was also demonstrated that the model provides a smooth transition to classical conservative behavior as alpha approaches unity, which confirms the physical validity of this representation. This demonstrates that fractional variational mechanics provides a consistent and physically meaningful way to describe the transition from conservative to dissipative behavior for coupled oscillating systems that are governed by memory and non-local effects.
Reliability, Validity and Turkish Adaptation of Self-Directed Learning Scale (SDLS)
(Ijate-INT Journal Assessment Tools Education, 2018) Demircioglu, Zeynep Isil; Cevik, Tugce; Ozcelik, Erol; Fucular, Emine Ezgi; Oge, Burak; Nazligul, Merve Denizci
Self-Directed Learning Scale (SDLS) developed by Lounsbury, Levy, Park, Gibson, and Smith (2009) was used for determining individuals' self-directed learning. The purpose of this study was to translate the SDLS into Turkish and to investigate its reliability and validity with a sample of 272 university students. The SDLS, the Modified Schutte Emotional Intelligence Scale (MSEIS), Self-Directed Learning Inventory (SDLI), and the Causal Uncertainty Scale (CUS) for determining convergent validity was applied to the participants. Factor analyses results verified the uni-dimensionality of the scale. The test-retest correlation of SDLS was 0.82, whereas Cronbach alpha coefficient of the scale was founded as 0.85 in the reliability analyses. Correlation coefficients representing for convergent validities varied from - 0.30 to 0.72 (p < .01) and criterion validity of the scale was determined as 0.236 when cumulative GPA was used as criterion in the assessment of concurrent validity. The findings suggest that the Turkish adaptation of SDLS is a valid and reliable tool to measure self-directed learning in Turkish samples.
Production and Retrieval off Rough Classes in Multi Relations
(IEEE Computer Soc, 2007) Sever, Hayri; Gorur, A. Kadir; Tolun, Mehmet R.
Organizational memory in today's business world forms basis for organizational learning, which is the ability of an organization to gain insight and understanding from experience through experimentation, observation, analysis, and a willingness to examine both successes and failures. This basically requires consideration of different aspects of knowledge that may reside on top of a conventional information management system. Of them, representation, retrieval and production issues of meta patterns constitute to the main theme of this article. Particularly we are interested in a formal approach to handle rough concepts. We utilize rough classifiers to propose a preliminary framework based on minimal term sets with p-norms to extract meta patterns. We describe a relational rule induction approach, which is called rila. Experimental results are provided on the mutagenesis, and the KDD Cup 2001 genes data sets.
Outputs Bounds for Linear Systems with Repeated Input Signals: Existence, Computation and Application to Vehicle Platooning
(Tubitak Scientific & Technological Research Council Turkey, 2018) Schmidt, Klaus Werner; Saglam, Harun Bugra
This paper investigates the effect of repeated time-limited input signals on the output excursion of stable, linear time-invariant systems. It is first shown that the maximum norm of the output signal remains bounded if the repeated input signals are separated by a nonzero dwell time. Then a novel method for computing a tight bound on the output signal norm is proposed. The setting of the paper is motivated by a vehicle platooning application, where vehicles repeatedly open/close gaps in order to perform lane changes. The developed method analyzes driving safety by computing a bound on the spacing error between vehicles when performing repeated open/close gap maneuvers.
Modeling and Analysis of a Microfluidic Capillary Valve
(Gazi Univ, 2017) Yildirim, Ender
Here, a numerical model for analysis of a capillary valve for use in microfluidic devices was presented. Capillary valves are preferred especially in passive microfluidic systems, where the capillary forces dominate the liquid motion, to manipulate the flow. The capillary valve in this work, was formed by the sudden expansion of a rectangular microchannel to an opening, whose depth and width are larger than the height and the width of the channel respectively. Noting that there was no available analytical model to determine the pressure capacity of such valves, a numerical model based on energy minimization was utilized. Free software Surface Evolver was used to solve the model. Dependence of the pressure capacity on the contact angle of the working liquid on the channel material was investigated. It was found that the pressure capacity of the valves would be maximum if the contact angle on all surfaces is 90 degrees. Accordingly, the valves could withstand approximately 2.5 kPa for 100 mu m x 100 mu m channels when the contact angle was 90 degrees. The model was verified by comparing the results with those available in the literature.
Messaging Brand Experience: Brand Ethicality, Brand Trust, Brand Attitudes
(Taylor & Francis Ltd, 2026) Ozsacmaci, Bulent; Kilic, Tamer; Dursun, Tolga; Celik, Suleyman
Messaging applications (e.g. WhatsApp/Telegram/Signal-type platforms) have become high-frequency touchpoints within integrated marketing communications. This study examines how the brand experience of messaging applications translates into brand attitudes through two parallel mechanisms: perceived brand ethicality and brand trust. We theorize that ethicality and trust serve as communication signals that arise from interface-level design and governance choices, such as plain-language privacy notices, granular consent flows, visible encryption and reliability cues, and third-party assurances. Using survey data from active messaging users, we validated the measurement model via CFA and tested a parallel-mediation structure with bootstrapped indirect effects. Results indicate that messaging brand experience exerts a positive direct effect on brand attitudes and significant indirect effects through both brand ethicality and brand trust, confirming that persuasion in messaging hinges on credibility and transparency signals embedded in the journey. Robustness checks across alternative specifications support these findings. Theoretically, the paper integrates behavioural foundations of persuasion with corporate communication by reframing governance artefacts as source/message credibility cues that shape ethical inferences and risk reduction. Managerially, the results recommend making ethical and reliability signals salient within messaging flows, aligning privacy-by-default language with value propositions, and orchestrating assurance elements across channels to improve attitudes and downstream performance.
Laminar Forced Convection Over An Inclined Flat Plate With Unheated Starting Length
(Gazi Univ, 2019) Turgut, Oguz; Ozcan, Ahmet Cem; Turkoglu, Hasmet
Two-dimensional laminar forced convection over an inclined flat plate with an unheated starting length was investigated numerically for both constant surface temperature and constant heat flux boundary conditions. The numerical study was implemented using the commercial software ANSYS Fluent 15.0. Air is used as working fluid. The influence of Reynolds number, inclination angle and the length of unheated plate on velocity and temperature distributions, surface temperature, surface heat flux and local Nusselt number was investigated. The results show that Reynolds number, inclination angle and the length of unheated region of plate play important role on heat transfer from the plate. It is seen that Nusselt number increases with increasing Reynolds number and inclination angle of inclined flat plate but decreases with increasing the length of unheated region of plate.
General Formulation of the Scattered Matter Waves by a Quantum Shutter
(Tubitak Scientific & Technological Research Council Turkey, 2009) Umul, Yusuf Z.
The scattering process of matter waves by a quantum shutter is investigated by using the spectrum integral representation. The scattered fields are expressed in terms of the Fresnel function. It is shown that the obtained equation gives the Moshinsky function for a one dimensional problem of the plane wave. Also a general integral representation is derived for two dimensional problems. The scattering of matter waves for some special wave-packets are examined analytically and numerically.
Finite Biorthogonal Polynomials Suggested by the Finite Orthogonal Polynomials Mnp,Qx
(Wiley, 2026) Guldogan Lekesiz, Esra
Constructing a biorthogonal structure from scratch, that is, defining a biorthogonal pair is quite tough. Because here the orthogonality must be established between two different sets. There are four known univariate biorthogonal polynomial sets, suggested by Laguerre, Jacobi, Hermite and Szeg & odblac;-Hermite polynomials, in the literature. In this paper, we derive for the first time a pair of finite univariate biorthogonal polynomials suggested by the finite univariate orthogonal polynomials . The corresponding biorthogonality relation and some useful relations and properties, including differential equation and generating function, are presented. Further, a new family of finite biorthogonal functions is obtained using Fourier transform and Parseval identity. In addition, we compute the Laplace transform and fractional calculus operators for the new biorthogonal polynomial set .
Exploring undefinedIundefined in Research: Reflexivity through a Lacanian Lens
(Routledge Journals, Taylor & Francis Ltd, 2026) Canbolat, Fazilet
This article explores reflexivity through a Lacanian lens, emphasizing the divided nature of the subject and the role of the unconscious in shaping reflexive practices. It examines the limitations of traditional definitions of reflexivity, which often focus on the self or ego, and offers a Lacanian perspective centered on the subject and the Borromean knot. By highlighting the roles of academic norms and expectations, language, ideal images, and unconscious forces, the article argues that reflexivity involves not only a dynamic negotiation between the researcher's subjectivity and academic structures but also the interplay of the imaginary, symbolic, and real dimensions of subjectivity. It also emphasizes how language exposes the often-overlooked real dimension within reflexivity.
Experimental Investigation of Granular Soil and Clay Interfaces with Direct Shear Tests
(MDPI, 2026) Ozturk, Sevki; Ergun, Mehmet Ufuk
This study experimentally investigates the shear strength behavior of interfaces formed between granular soils and clay under drained conditions, with particular emphasis on peak-to-residual strength evolution. Large and small-scale direct shear tests were performed on clay, granular soils (sand and gravel), and their interfaces, and shearing was continued to large displacements to reliably capture residual behavior. Unlike most previous studies that focus on soil mixtures, this study explicitly quantifies interface-specific shear strength parameters and highlights their distinct mechanical response. The results show that while interface cohesion remains comparable to that of clay, the interface friction angle is consistently higher. Specifically, under residual conditions, the friction angle of the clay (12.9 degrees) increased to 16.4 degrees for the sand-clay interface and to 19.8 degrees for the gravel-clay interface. These findings demonstrate that adopting clay residual parameters for granular soil-clay interfaces may be overly conservative and that interface-specific residual friction angles should be considered in stability analyses of slopes and earth structures.
Effects of Routing Algorithms on Novel Throughput Improvement of Mobile Ad Hoc Networks
(Tubitak Scientific & Technological Research Council Turkey, 2012) Preveze, Barbaros; Safak, Aysel
A cognitive method called most congested access first (MCAF), minimizing the packet loss ratio and improving the throughput of a multihop mobile WiMAX network, is proposed. MCAF combines both the time division multiple access and the orthogonal frequency division multiple access methods. MCAF additionally uses spectral aid and buffer management methods, which air proposed in this paper, to manage both spectrum. access and packets in the buffers. By using these novel methods, real-time video and voice packet transmission is achieved, data packet loss rate is minimized, and the system throughput per node is improved. Effects of fastest path and ant colony routing algorithms on throughput improvement methods are investigated. It is shown that the fastest path routing algorithm, provides higher throughput values than the ant colony routing algorithm.

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