The annual performance of a hybrid system of a flat plate photovoltaic thermal system and a solar thermal collector (PVT/ST) is numerically analyzed from the energy, exergy, and environmental (CO2 reduction) viewpoints. This system can produce electricity and thermal power simultaneously, with higher thermal power and exergy compared to conventional photovoltaic thermal systems. For this purpose, a 3D transient numerical model is developed for investigating the system's performance in four main steps: (1) investigating the effects of the mass flow rate of the working fluid (20 to 50 kg/h) on the temperature behavior and thermodynamic performance of the system, (2) studying the impacts of using glass covers on the different parts of the system, (3) evaluating the annual energy and exergy analyses of the system under Mashhad weather conditions, and (4) examining the CO2 reduction by using the proposed system. The results show that for the (glazed) PVT and (glazed) ST systems, increasing the mass flow rate of the working fluid from 20 to 50 kg/h results in 22% and 1.5% improvements in both thermal and electrical power, respectively. However, the thermal exergy of the system decreases by 40.1%. Furthermore, the (glazed) PVT/(glazed) ST systems generate approximately 86% and 264% more thermal power and energy than the PVT/ST systems, respectively. Using a (glazed) PVT/(glazed) ST system with a working fluid’s mass flow rate of 50 kg/h results in maximum thermal and electrical efficiencies of 40.7% and 16.22%, respectively. According to the annual analysis, the highest average thermal and electrical power, equal to approximately 338.3 and 24 W, respectively, is produced in August. The amount of CO2 reduction increases by increasing the mass flow rate and using a glass cover. The PVT/(glazed)ST system has the potential to reduce CO2 emissions by 426.3 kg per year.
Airway-centric orthodontics has been proposed as a conceptual framework that extends the traditional understanding of craniofacial development, functional disturbances, and orthodontic treatment outcomes beyond a purely dental perspective. This approach focuses on the potential interplay among upper airway characteristics, breathing patterns, and orofacial muscle function in influencing facial growth and occlusal relationships. This narrative review aims to outline the theoretical foundations of airway-centric orthodontics and to synthesize current evidence regarding the associations among upper airway characteristics, craniofacial morphology, and orthodontic interventions. A compr
The present systematic review aimed to combine the evidence on rodent models on molecular regulators of root dentinogenesis across the temporal phases and spatial zones, and evaluate the translation of this map for human dental development and regenerative therapies. A PRISMA 2020‑guided systematic review of experimental studies through the major electronic databases was performed. Data on models, molecules, techniques, spatiotemporal expression and the functional outcomes were extracted. The ARRIVE guidelines and SYRCLE's risk of bias tool were used to assess the risk of bias in animal studies. The evidence form rodent studies supports an organized network that begins with initiation at the cervical loop that requires the downregulation
... Show MoreIn recent years, the evolution of the community structure in social networks has gained significant attention. Due to the rapid and continuous evolution of real-world networks over time. This makes the process of identifying communities and tracking their topology changes challenging. To tackle these challenges, it is necessary to find efficient methodologies for analyzing the behavior patterns of dynamic communities. Several previous reviews have introduced algorithms and models for community detection. However, these methods have not been very accurate in identifying communities. Moreover, none of the reviewed papers made an apparent effort to link algorithms that can accurately detect dynamic communities. This review aims to present a ta
... Show MoreThe calibration of a low-speed wind tunnel (LSWT) test section had been made in the present work. The tunnel was designed and constructed at the Aerodynamics Lab. in the Mechanical Engineering Department/University of Baghdad. The test section design speed is 70 m/s. Frictional loses and uniformity of the flow inside the test section had been tested and calibrated based on the British standards for flow inside ducts and conduits. Pitot-static tube, boundary layer Pitot tube were the main instruments which were used in the present work to measure the flow characteristics with emphasize on the velocity uniformity and boundary layer growth along the walls of the test section. It is found that the maximum calibrated velocity for empty test s
... Show MoreAim: This article aims to review the studies on the bond strength between dental ceramics and metal restoration in crowns and bridges using various techniques. Methodology: Electronic databases for scientific research, including PubMed, Cochrane, and Medline, were searched. The following keywords were used: dental ceramic, cobalt-chromium (Co-Cr) alloy, shear bond strengths, Selective Laser Melting (SLM) technique, sandblasting technique, three-point bending test, hardness test, mode of failure, Scanning Electron Microscope (SEM) and roughness test. Initial retrieval of 86 original papers from the worldwide databases was done after careful screening, including reviews of the literature on the different techniques used to enhance the shear b
... Show MoreWhen scheduling rules become incapable to tackle the presence of a variety of unexpected disruptions frequently occurred in manufacturing systems, it is necessary to develop a reactive schedule which can absorb the effects of such disruptions. Such responding requires efficient strategies, policies, and methods to controlling production & maintaining high shop performance. This can be achieved through rescheduling task which defined as an essential operating function to efficiently tackle and response to uncertainties and unexpected events. The framework proposed in this study consists of rescheduling approaches, strategies, policies, and techniques, which represents a guideline for most manufacturing companies operatin
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