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Unveiling Communication Quality in the Construction Industry: A Multilevel Evaluation of Project, Group, and Individual Outcomes
No full textConfronted with the multifaceted risks associated with the construction industry, communication quality is considered as an indispensable need for improving project success. Past research on communication in construction has made significant progress; however, existing literature lacks a multilevel framework that captures factors influencing construction employees’ communication quality across a three-level-hierarchy: (1) project level (top), (2) group level (medium), and (3) individual level (bottom). The present study addresses this gap by developing a conceptual model showing the effects of operational hierarchic levels (i.e., project, group, and individual levels) on communication quality, as well as including project complexity as a moderating variable. Using the data collected from 447 construction professionals, structural equation modeling (SEM) analysis uncovers the role of exploring different perspectives at project level and shared vision at individual level in maintaining high-quality communication among project teams. The results of the moderation analysis reveal that project complexity has an interaction effect with team diversity and shared vision, which also influences communication quality. This study provides valuable insights into communication in construction, aiding practitioners to improve their communication performance and develop effective communication strategies. The findings contribute to the understanding of significant contextual and individual factors by proposing a model that detects project’s process of reflection and exploration (project level), practitioners’ varying cultural and professional backgrounds (group level), and their personal innovative and collective acts (individual level), underpinning their importance in ensuring the quality of communication.</p
A hybrid numerical method approach for the two-dimensional coupled Burgers' equations with nonlinearity preservation
No full textIn this study, we develop a novel hybrid numerical method based on the finite element method and finite difference method for solving the two-dimensional coupled Burgers' equations. The time discretization is achieved by applying a backward finite difference approximation. The proposed hybrid method is evaluated using three challenging shock wave problems of Burgers' equation with different values of parameters. The most outstanding feature of the combined method is that the proposed hybrid method is applied without linearization of the two-dimensional coupled Burgers' equations and preserving the nonlinearity of the model equations. To the authors' knowledge, this study represents the first successful application of the proposed numerical method capable of solving the governing equations for large time levels and extremely low viscosity values (epsilon=0.00001) with minimal computational cost. Numerical experiments validate the accuracy and convergence order of the method, demonstrating its advantage over exact and previously reported solutions
A decision-support framework for sustainable hydrogen refueling stations under solar variability and tariff reforms
No full textThe large-scale deployment of sustainable hydrogen refueling stations (HRS) faces critical barriers from siting constraints, solar resource variability, and electricity tariff reforms that reshape grid economics. While previous studies often address these drivers in isolation, they rarely capture the trade-offs of photovoltaic (PV)-electrolyzer-hydrogen storage scaling under real-world conditions. This study develops a high-resolution techno-economic-environmental framework that evaluates HRS performance under land-use limitations, solar variability, tariff reforms, and hydrogen storage autonomy scenarios. Results show that siting constraints and tariff reforms can push grid dependency above 70% and hydrogen costs up to 15.8 /kg and cut CO2 emissions by more than 70%. These optimal cases occur where PV self-consumption remains around 55%-65%, reflecting efficient utilization and balanced operation. By contrast, oversizing PV without improving self-consumption ratio (SCR) raises curtailment to 55%. Extending storage autonomy further strengthens energy security and reduces emissions, but also lengthens payback periods, underscoring the dual nature of autonomy. Overall, the framework delivers actionable insights for policymakers and investors, linking siting constraints, solar variability, and tariff reforms to the design of resilient, cost-effective, and sustainable hydrogen infrastructures that support long-term energy security
Design and application of boron-based photocatalysts toward sustainable hydrogen production
No full textInfrared Drying of Carrot Slices: Effect of Power Levels on Kinetics and Energy Efficiency
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Energy yield from the two-layered Bosphorus exchange flow by marine current turbines: Challenges and implications
No full textCompared to tidal currents, which have been extensively researched in recent years, relatively little attention has been paid to the energy potential of waterways characterised by non-tidal or stratified ocean currents, such as the Bosphorus Strait in Istanbul. Therefore, it is essential to highlight the significance of such domains in the context of marine renewable energy and to provide scientific approaches for assessing their resource potential. This study identifies key considerations for determining suitable Marine Current Turbine (MCT) deployment sites in a sea strait with a stratified flow structure and proposes a site selection methodology accordingly. Floating MCTs were found to be more suitable for capturing the hydrokinetic energy flux of the upper-layer flow toward the southern end of the strait. The spatiotemporal variation in layer thickness was a decisive factor in determining optimal MCT rotor geometry and deployment depth. Turbines notably altered the flow field, particularly during periods of peak current velocities. The MCTs were operational for approximately 80 % of the simulated year and produced an average power of 60 kW. The maximum average power recorded by a single MCT within the turbine array was 83 kW
KENT KİMLİĞİNİ YANSITACAK VE İKLİM DEĞİŞİKLİĞİNE UYUM SAĞLAYABİLECEK ODUNSU BİTKİLER: BALIKESİR
No full textEnhanced Supercapacitor Performance of Polyindole Nanocomposites via Optimized 2D SnS2 Nanosheet Integration: Structural, Optical, and Electrochemical Investigations
No full textThis study addresses the growing demand for sustainable energy storage by developing high-performance supercapacitor electrodes based on polyindole (PIn) nanocomposites integrated with 2D SnS2 nanosheets. Using cost-effective and scalable hydrothermal and chemical oxidative polymerization methods, the electrodes were fabricated via spin coating. Structural (XRD, FE-SEM, and SEM), optical (UV–Vis), and electrochemical (CV, GCD) analyses reveal that the 3% SnS2-doped composite exhibits a specific capacitance of 188 F/g and an energy density of 25.04 Wh/kg, outperforming pure PIn and many previously reported PIn-based systems. The layered morphology of SnS2 enhances ion transport and faradaic activity, making this composite a promising candidate for environmentally friendly hybrid energy storage applications
Identifying and Assessing Suspension Risks of Public Infrastructure Projects
No full textPurpose: The long construction period of public infrastructure projects increases the probability of facing political and economic turmoil, which might be triggered by national and/or international instabilities. Combined with the chronic peculiarity of these projects, such as delays and cost overruns, political and economic turmoil could lead to the temporary suspension of public infrastructure projects since the governments and/or public authorities fail to allocate sufficient financial resources. However, suspension decision for public infrastructure projects poses a wide range of risks that are widely neglected in the literature. Thus, this study proposes a suspension risk management framework by identifying and assessing the risks that may arise after the suspension of public infrastructure projects. The study also investigates perception differences among the leading stakeholders of the public infrastructure projects to ensure that the stakeholders could formalize shared risk response strategies. Initially, a comprehensive literature review and focus group discussion (FGD) sessions were conducted to identify the suspension risks. Next, the questionnaire survey and fuzzy TOPSIS analysis were jointly implemented to determine the significance of each risk. Finally, Cronbach’s alpha analysis and the Mann-Whitney U test were implemented to examine the reliability of the dataset and the perception differences. The results indicated that the suspension decision of infrastructure projects has financial, technical, managerial, social, and environmental implications. Therefore, the suspension risks proposed in this study should be analyzed deeply before the suspension decision is given. Besides, the results pinpointed risks such as “Uncertainties due to constant changes in the contract,” “Financial losses arising from the judicial and/or alternative dispute resolution processes,” and “Administrative difficulties in obtaining financing in the re-starting period” as the most critical suspension risk factors, necessitating urgent and comprehensive risk response strategies. Lastly, the Mann-Whitney U test validated that the proposed framework could be implemented by contracting parties to formulate shared risk response strategies in infrastructure projects.</p