This study evaluates a sustainable preplaced aggregate (two-stage) fiber-reinforced concrete (PAFRC) that incorporates Portland limestone cement (PLC) and high dosages of polypropylene (PP) and alkali-resistant glass (GF) fibers. Aggregates and fibers were preplaced in the formwork and subsequently injected with a flowable grout; mechanical performance was assessed at 28 days. The results indicate that 4% PP increased compressive strength, splitting-tensile strength, and elastic modulus by 15.2%, 15.9%, and 18.6%, respectively, whereas 1% and 2% GF improved flexural strength by 10.2% and 10.4%, respectively. The 2% PP mixture exhibited the highest compressive strength (20.3 MPa), and the 4% PP mix attained the greatest splitting-tensile strength (3.6 MPa). Peak flexural performance (4.9 MPa) was observed for both the 6% PP and 2% GF mixes. Incorporating PLC in the PAFRC system reduces clinker demand and embodied CO2, and the preplaced method enables higher fiber contents without severe segregation. These results demonstrate a practical pathway to enhance both the mechanical performance and sustainability of concrete for repair and structural applications.

In recent years, researchers have been investigating different alloying elements to improve the corrosion resistance of magnesium alloys. One such element is Yttrium (Y), which has shown promising results in enhancing the corrosion resistance of magnesium alloys, such as EZ33. The susceptibility of magnesium alloys to corrosion is a major challenge, as corrosion can lead to structural degradation and compromise the integrity of the material, especially in harsh environments. The influence of a single yttrium (Y) addition on the corrosion resistance of the EZ33 Mg alloy was examined in this work. The corrosion resistance was measured using the loss weight method, and the specimens' surfaces were examined using an optical microscope and a scanning electron microscope. The results showed that the corrosion rate decreased with the addition of Y, and microstructure examination illustrated that the corrosion product film formed at the alloy treated with Y was more stable than those formed at the microstructure of the base alloy. Moreover, the corrosion attacked the area where the intermetallic phases formed, which was shown via optical microscope images. Y can be an effective alloying element to enhance the durability of Mg alloys in structural or biomedical applications.

Nowadays, using advanced structural materials such as preplaced aggregate concrete (PAC) and fiber-reinforced preplaced aggregate concrete (FR-PAC) are widely investigated due to their benefits in designing infrastructures. Therefore, finding the mechanical characteristics of PAC and FR-PAC can be help structural engineers. This study explores the material characteristics, performance, and potential challenges associated with using PAC and FR-PAC, aiming to provide insights into their practical implementation and long-term benefits in construction. In addition, a superior estimation tool based on multi-target stacked machine-learning (ML) model was introduced to reduce the cost of experimental tests and increase the accuracy and speed of finding the best mixture for PAC and FR-PAC. Experimental tests were conducted to prepare unseen dataset to validate the general ability of the ML models. Results show that the proposed multi-target stacked ML models can estimate the compressive and tensile strengths of PAC specimens with an accuracy of 97.4% and 94.7%, respectively; however, for compressive, flexural, and tensile strengths FR-PAC specimens, the accuracy of 97.7%, 98.0% and 98.3%, were determined, respectively. The proposed predictive model was turned into a graphical user interface (GUI) with ability on predicting the mechanical properties of PAC and FR-PAC in different curing day, and updating the database in future.

This study investigates the innovative integration of Portland limestone cement (PLC) and date palm ash (DPA) in preplaced aggregate concrete (PAC) grouts, addressing the urgent need for sustainable construction materials with a lower carbon footprint. With the construction industry contributing significantly to global CO2 emissions, utilizing agricultural by-products like DPA offers an eco-friendly alternative while mitigating waste disposal challenges. The research evaluates single, binary, and ternary binders incorporating supplementary cementitious materials such as silica fume (SF) and metakaolin to optimize PAC's mechanical properties. Findings reveal that binary grouts with PLC and 10% SF achieved the highest compressive strength (68.3 MPa), outperforming traditional mixtures by 40%. Microstructural analysis confirmed that DPA enhances matrix density and reduces pore size, contributing to improved durability. Recommendations include further exploration of DPA's role in reducing cement content and promoting resource efficiency. The findings highlight PLC and DPA as viable components for greener construction, advancing PAC's potential as a sustainable concrete for structural applications.

This study presents an assessment of the feasibility of implementing a hybrid renewable energy-based electric vehicle (EV) charging station at a residential building in Tripoli, Libya. Utilizing the advanced capabilities of HOMER Grid software, the research evaluates multiple scenarios involving combinations of solar and wind energy sources integrated with energy storage and the utility grid. This analysis provides a novel approach to enhancing urban energy systems with renewable technologies in a region traditionally reliant on fossil fuels. Key contributions of this study include the demonstration of an innovative integration strategy that combines solar and wind power with battery storage to ensure a reliable and efficient energy supply for EV charging. Furthermore, the study addresses the practical implications for local energy policy, suggesting that such hybrid systems can significantly enhance energy security and support sustainable urban development. The authors studied five scenarios using HOMER. The results reveals that the annual total costs and payback periods are as follows: for Scenario 1 (wind/utility grid), the expenditure totals US $1,554,416 and payback period of 4.8/5.8 years; for Scenario 2 (solar/wind/Utility grid), the amount is US $1,554,506 and payback period of 4.8/5.8 years; and for Scenario 3 (solar/wind/storage/utility grid), it escalates slightly to US $1,554,731, all predicated on the utility grid tariffs and payback period of 4.8/5.8 years. Furthermore, in Scenario 4 (solar/utility grid), the annual total cost is significantly reduced to US $30,589 and a payback period of 8.1/14.3 years, while Scenario 5 (solar/storage/utility grid 

This study proposes a novel approach by adding Portland limestone cement (PLC) to preplaced aggregate steel fiber reinforced concrete (PASFRC) to create a sustainable concrete that minimizes CO2 emissions and cement manufacturing energy usage. The method involves injected a flowable grout after premixing and preplacing steel-fibers and aggregates in the formwork. This study evaluates the mechanical properties of a novel sustainable concrete that uses PLC and steel fibers. To achieve the intended objective, long and short end-hooked steel fibers of 1%, 2%, 3%, and 6% were incorporated in PASFRC. Also, Analysis of variance (ANOVA) was used to examine the data. Results indicated that PLC and higher fiber doses increased the mechanical properties of PAC. At 90 days, PASFRC mixtures containing 6% long steel fibers demonstrated superior compressive, tensile, and flexural strengths, registering the highest values of 49.8 MPa, 7.7 MPa, and 10.9 MPa, respectively and differed by 188%, 166%, and 290%, respectively from fiberless PAC. The study confirmed the suitability and effectiveness of using PLC with steel fibers in PAC which significantly improved the mechanical properties of PASFRC. This was verified through analytical analysis and new empirical equations were proposed to predict the mechanical properties of PASFRC.

A smart home is a technologically equipped residence that proactively observes its residents and offers various services. It has emerged as a potential solution to support independent living for people with disabilities and older adults, while also relieving the burdens on family caregivers and healthcare providers. A fundamental aspect of smart homes is their capability to monitor daily living activities and ensure residents' safety by detecting changes in their routines. With the advancements in technology, modern smart homes are furnished with numerous low-power sensors, radios, and embedded processors that collaboratively process data to assess the home's state and the behaviors of its occupants. This article delves into the sensor technology employed in smart homes, with a particular focus on direct environment sensing and infrastructure-mediated sensing. It explores the strengths and limitations of different sensor technologies and discusses the challenges and opportunities from technical, and ethical perspectives.

This research aims to develop a computer model of a hybrid renewable energy system that can operate independently for a faculty of engineering of Karabuk university, located in Turkey. The hybrid system consists of several components, such as Photovoltaic (PV) panels, wind turbines, diesel generator, and battery storage system as a backup. The primary purpose of this system is to meet the energy needs of a university building. Different combinations of the hybrid system were examined using HOMER software to determine the most cost-efficient solution based on the net present cost. Following the analysis of multiple combinations, the optimal hybrid system was determined, which consists of a 500kW PV system, wind turbines with a total capacity of 7.5 MW, and a 327Ah, 15.7 kw/h battery storage system, diesel generator of 2000 kw. The overall cost of the system $693,000,000, the project lifespan is 25 years.