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The differential effects of leader Food safety priority and ethical leadership on food safety promotive and prohibitive voices: A socially desirable responding theory perspective
No full textStudies on impact of different leadership styles on the promotive and prohibitive forms of food safety voices are limited. Therefore, drawing on socially desirable responding theory, this study examined the differential effects of leader food safety priority and ethical leadership on food handlers’ promotive and prohibitive forms of food safety voices. We found that leader food safety priority and ethical leadership influence employee voice through different mechanisms. Moreover, the indirect impact of leader food safety priority on promotive voices was stronger, while ethical leadership had a stronger indirect effect on prohibitive voice. Finally, leader–member exchange strengthened the indirect effects of leadership antecedents on both forms of food safety voices. This study provides theoretical and practical contributions to food safety voice literature
A predictive multistage postdisaster damage assessment framework for drone routing
No full textThis study focuses on postdisaster damage assessment operations supported by a set of drones. We propose a multistage framework, consisting of two phases applied iteratively to rapidly gather damage information within an assessment period. In the initial phase, the problem involves determining areas to be scanned by each drone and the optimal sequence for visiting these selected areas. We have adapted an electric vehicle routing formulation and devised a variable neighborhood descent heuristic for this phase. In the second phase, information collected from the scanned areas is employed to predict the damage status of the unscanned areas. We have introduced a novel, fast, and easily implementable imputation policy for this purpose. To evaluate the performance of our approach in real-life disasters, we develop a case study for the expected 7.5 magnitude earthquake in Istanbul, Turkey. Our numerical study demonstrates a significant improvement in response time and priority-based metrics.TÜBİTAKPublisher versio
An overview of integrated balance rehabilitation (I-BAR) framework
No full textNeurological diseases impact around 1 billion people globally, with the numbers expected to increase due to population growth and aging, leading to a decline in lifestyle quality. The need of the hour is to develop a comprehensive methodology for ankle, balance, and step-taking rehabilitation for improving postural adjustment strategies (motor learning) in patients with different disease severity. To meet this need, we propose the Integrated Balance Rehabilitation (I-BAR) framework, designed to boost rehabilitation effectiveness through objective assessment, personalized therapy, and adaptability to different disability levels. I-BaR combines ankle-foot preparation, balance, and stepping phases into a cohesive process. It offers multi-modal feedback: visual feedback via virtual reality, vestibular feedback through robotic platform-induced perturbations, and proprioceptive feedback using haptic feedback, enabling patients to improve their balance abilities comprehensively.TÜBİTA
Maternal symptoms and emotional availability predicting children's behavior problems: A longitudinal study
No full textQuasi-omnidirectional vehicular VLC: Design, implementation, and experimental validation
No full textVisible Light Communication (VLC) is emerging as a compelling solution for future vehicular networks due to its high bandwidth and immunity to radio frequency (RF) interference. However, its relatively directional nature poses significant challenges in dynamic driving environments. This paper presents the first comprehensive experimental evaluation of a quasi-omnidirectional vehicular VLC system integrating dual headlight transmission with six photodetector (PD) receiver architecture. The system is implemented on a software-defined radio (SDR) platform and evaluated across a range of real-world driving scenarios including curved roads, intersections (T- and Y-junctions), and multilane settings. Through extensive outdoor measurements under static and mobile conditions, we demonstrate that our system achieves 100% packet delivery ratio (PDR) up to 15 meters in all scenarios and up to 29 meters under ideal alignment. We further compare select best combining (SBC) and equal gain combining (EGC) schemes, identifying SBC as the superior approach due to its noise robustness. Our findings show that strategically placed side and rear PDs play a critical role in maintaining connectivity during vehicular maneuvers, such as lane changes and turns. This study validates the feasibility and effectiveness of multi-PD vehicular VLC systems and provides key design insights for their integration into Intelligent Transportation Systems.Tamkeen under the Research Institute NYUAD ; EU Horizon 2020 MSCA-ITNPublisher versio
Adaptive optimization approach for production and distribution planning of perishable food products under demand uncertainty
No full textManagement of production and distribution planning of perishable food products is crucial due to their low-profit margin and the increased environmental costs of manufacturing. The production planning of perishable products is challenging as it combines multiple factors such as temperature tracking of products, sequence-dependent facility setup cost, and uncertain demand in one setting. This paper studies the production and distribution planning problem for perishable food products and unifies the mentioned factors in an optimization framework. We propose an adaptive optimization approach to address the uncertainty in demand, providing flexible optimization approaches for a multi-period planning horizon. The first approach is adjustable robust optimization that generates a resilient and Pareto-efficient production and distribution plan to tackle demand uncertainty avoiding over-conservative solutions via decision rules. The second is the folding horizon, which re-optimizes production and distribution plans based on the realized demands over time. We assess the efficiency of the adaptive approach through extensive Monte Carlo simulation experiments. Furthermore, we perform a real-case adoption study on the production planning of a dairy factory to assess the applicability of our model and solution approach in real-world instances. According to the results, the adjustable approach and the folding horizon approach improve the objective function value by 4-14% and 5-28% for that of the orthodox robust model. The numerical results also show that the adjustable robust approach is always resistant to uncertainty, while the percentage of unmet demand for the deterministic model can reach as high as 18%.TÜBİTAKPublisher versio
Experimental and numerical analysis of hot deformation during press forming of Ti-6Al-4V alloy for aerospace applications
No full textIn this study, hot press forming of an aero-structural Ti-6Al-4V sheet was examined by experimental and numerical simulation. The effects of hot forming parameters were examined in experiments performed at 700 degrees C and 800 degrees C forming temperatures, 0.5 mm/s and 2 mm/s intervals, different press tonnages and holding times. Stress and equivalent plastic strain distributions and shell thickness changes during forming were estimated with finite element analysis in ABAQUS-CAE software. According to the results, it was seen that the most significant effect on formability among the forming parameters was temperature, and the forming tonnage and holding time were also effective. With the finite element model created, the material behavior could be predicted numerically with high accuracy.TÜBİTAK ; Scientific Research Program of Turkish Aerospace Industries ; Özyeğin Universit
Dynamics of pulsed-laser interaction with janus particles
No full textJanus particles, with their flexible chemistry and multifunctionality, have broadened the scope of the optical manipulation field as an emerging class of materials. Laser-based manipulation is particularly promising for half-metal-coated particles, offering a platform to study optical and thermal effects. However, the role of the laser's operation regime in particle behavior needs to be understood better. Hence, in this work, we studied the interaction of nanosecond-pulsed lasers on 4.1 mu m Au-Janus particles with a 100 nm gold cap. We focused on the interaction in three sections: (1) We observed three pulse energy influence regimes: In the low-influence regime (less than similar to 10 nJ), the particle maintains its intrinsic Brownian motion. In the medium-influence regime (less than similar to 40 nJ), the particle exhibits an extended range of motion. In the high-influence regime (higher than similar to 40 nJ), the particle undergoes superdiffusion and establishes a new equilibrium position. (2) During optical manipulation trials, a threshold pulse energy of 4 nJ (average power of 40 mu W) was sufficient to move Au-Janus particles against the laser spot. We achieved translation velocities of 0.9-5.1 mu m/s at 4-50 nJ. (3) The gold cap is damaged at 20 nJ (fluence of 0.7 J/cm2) when the laser is focused on the particle, consistent with theoretical predictions, and the ablation process generates micro- and submicrometer gold particles. These findings reveal the potential of pulsed lasers for precise, power-efficient manipulation of Janus particles, advancing our understanding of laser-particle interactions and opening new pathways for optical manipulation applications.European Union Horizon 2020 ; TÜBİTA
The value of diversification: ESG and investment in controversial industries
No full textThis paper investigates the impact of Environmental, Social, and Governance (ESG) disclosure on the value of diversification and how investment in controversial industries (sin and energy) by conglomerate firms affects their ESG scores and valuations. I find that conglomerates with higher ESG scores have higher diversification values. Following an investment in controversial industries, conglomerate firms experience a significant decline in their ESG scores and valuations. Moreover, the negative impact of investments in con-troversial industries on the value of diversification is mitigated by higher ESG disclosure. After the Paris Agreement, in high ESG awareness period, excess values of conglomerates with higher ESG scores increase, indicating a causal effect
Digital transformation and cybersecurity risks
No full textThis study analyzes the impact of integrating cybersecurity measures on the financial performance of banks. Utilizing regression analysis with data from 100 financial institutions, the findings reveal that banks prioritizing cybersecurity perform better financially. This study demonstrates that it is the quality and strategic integration of cybersecurity measures, as revealed through disclosures, that significantly influence financial outcomes, rather than the sheer scale of investment. A subsample analysis suggests that larger banks appear more resilient to cybersecurity threats due to scale-related advantages, while smaller banks can also improve their financial performance by adopting proportionate, strategically aligned cybersecurity measures. Effective cybersecurity integration correlates with improved financial metrics such as return on assets and equity. Furthermore, the severity of cybersecurity incidents negatively impacts financial performance, emphasizing the importance of proactive risk management. This study underscores the critical role of cybersecurity in financial strategy, enabling banks to navigate digital transformation challenges effectively