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The overuse of conventional fuels (coal, petroleum products, and gas) for energy generation causes natural resource depletion and global warming. Therefore, the utilization of Renewable Energy Sources (RES) in power systems is seeing rapid growth on a global level, particularly in offshore locations. This work aims to review the progress in developing hybrid RES power systems in offshore environments and optimization methods used for power generation using solar, wind, and wave energy systems. The papers published in peer-reviewed journals were collected from 2000 to 2023. A total of 143 articles were obtained and analyzed. The results demonstrated a rising trend in annual publications about the use of hybrid RES in electricity generation since 2007. The hybrid solar-wind and wind-wave energy systems have received a lot of attention due to technical advancements already developed for the wind energy system. Machine learning techniques, such as genetic algorithms (GA) and particle swarm optimization (PSO), have been extensively utilized in the field of renewable energy systems for tasks such as optimizing unit sizes, determining appropriate unit placements, minimizing costs, and maximizing power output. The methods are preferred due to their less complex structure. However, the practical application, true cost estimation and installation and maintenance studies at offshore locations are poorly developed. Also, the hybrid solar-wave and solar-wind-wave RES systems need further investigations for optimal mixing at the feasibility stage. The current review is the first of its kind, focusing on offshore renewable energy systems only.

Currently, the field of structural health monitoring (SHM) is focused on investigating non-destructive evaluation techniques for the identification of damages in concrete structures. Magnetic sensing has particularly gained attention among the innovative non-destructive evaluation techniques. Recently, the embedded magnetic shape memory alloy (MSMA) wire has been introduced for the evaluation of cracks in concrete components through magnetic sensing techniques while providing reinforcement as well. However, the available research in this regard is very scarce. This study has focused on the analyses of parameters affecting the magnetic sensing capability of embedded MSMA wire for crack detection in concrete beams. The response surface methodology (RSM) and artificial neural network (ANN) models have been used to analyse the magnetic sensing parameters for the first time. The models were trained using the experimental data obtained through literature. The models aimed to predict the alteration in magnetic flux created by a concrete beam that has a 1 mm wide embedded MSMA wire after experiencing a fracture or crack. The results showed that the change in magnetic flux was affected by the position of the wire and the position of the crack with respect to the position of the magnet in the concrete beam. RSM optimisation results showed that maximum change in magnetic flux was obtained when the wire was placed at a depth of 17.5 mm from the top surface of the concrete beam, and a crack was present at an axial distance of 8.50 mm from the permanent magnet. The change in magnetic flux was 9.50 % considering the aforementioned parameters. However, the ANN prediction results showed that the optimal wire and crack position were 10 mm and 1.1 mm, respectively. The results suggested that a larger beam requires a larger diameter of MSMA wire or multiple sensors and magnets for crack detection in concrete beams.

With the increased use of engineered cementitious composite (ECC) in closed environments and as a structural material, it is necessary to fully understand its performance under elevated temperatures. This research investigates the response of ECC to ambient and elevated temperatures and addresses the issue of explosive spalling by incorporating graphene oxide (GO) and crumb rubber (CR). Twenty GO-modified rubberized ECC mixes were designed using Response surface methodology (RSM), considering GO content, GO concentration for CR pretreatment, CR replacement of fine aggregate, and elevated temperature as the input variables. Results show that mixes with GO and GO-treated CR outperform those without GO or untreated CR at ambient and elevated temperatures. Response predictive models exhibited high coefficient of determination (R2) values ranging from 84 % to 96 %. Multi-objective optimization yielded optimum input factors, resulting in improved mechanical properties that were experimentally validated to confirm the accuracy of the developed models.

There is a need in enhancing high-density concrete (HDC) for safeguarding sub-sea pipelines and constructing concrete mattresses for pipeline stabilization. To tackle these issues, a novel approach using a combination of supplementary cementitious materials like fly ash (FA) and graphene oxide (GO) have been successfully used in the partial replacement of the cement in this study. This research aims to enhance density, water resistance, and compressive strength properties for offshore applications by using GO and FA. A central composite design (CCD) of the response surface methodology (RSM) was employed, generating thirteen mixes with varying dosages of GO in the range of 0.013%–0.053% by weight of the cement and FA in the range of 20%–50% by weight of the cement. The HDC mixes exhibited enhanced characteristics, including an increased density of 4282 kg/m³, a maximum compressive strength of 37.9 MPa, and reduced water absorption at 2.52%. Response predicted models were established and validated through ANOVA, and multi-objective optimization was performed at a desirability of 58%. This yielded optimal GO and FA dosages of 0.013% and 37.87% respectively, for HDC with improved performance. The R2 values for the models range from 70% to 96%, showing a good level of the model quality. The findings present promising opportunities for more sustainable, cost-effective, and environmentally friendly HDC solutions for offshore applications.

Crumb rubber (CR) pretreatment methods effectively mitigate mechanical strength loss in cementitious composites. Yet, their impact on composite durability remains underinvestigated. This study examines the effect of CR pretreatment with graphene oxide (GO) on the durability of rubberized engineered cementitious composite (RECC), employing response surface methodology (RSM) for predictive model development and optimization. Water absorption, sulfate and acid resistance, compressive strength, and the porosity using mercury intrusion porosimetry were evaluated across 16 RSM-generated mixes using five GO concentrations (GOC) (0–1 mg/mL) and three pretreated CR (PCR) replacement levels (1–5%) as input variables. Results reveal increased resistance to water absorption, expansion, weight, and strength loss in sulfate and acid media with higher GOC levels across all PCR groups. Developed response predictive models demonstrate high R2 values (53–97%). Optimization resulted in 0.73 mg/mL and 2.5% for GOC and PCR, respectively.

A crucial aspect of the design approach for bar-reinforced concrete buildings is the proper transfer of loads between the concrete and steel reinforcement via bonding. Bar pull-out tests were done to see how graphene oxide (GO) affected the bond strength, bond energy, and bond stress–slip response of deformed reinforcing bars implanted in engineered cementitious composites (ECC). This was done to improve the bond strength of steel/concrete composites. This article examines the bonding behaviour of steel reinforcing bars in a mixture of GO-modified ECC. The findings of pull-out assessments conducted on two distinct diameters (12 and 16 mm) of reinforcement steel bar inserted in ECC are initially provided. The investigation's findings are then utilised to determine the bond-slip interactions that describes the relations between the ECC mixtures and steel reinforcement bars. According to the experiment results, the introduction of GO as a nano-reinforcement in the ECC mixture had a considerable positive effect on the bar-matrix interactions owing to its bridging function. After 28 days, the bond strength of steel bars with widths of 12 and 16 mm was increased by 54.80% and 26.70%, respectively, when 0.05 wt% of GO was added to 1% of PVA fibre. The response surface methodology (RSM) is employed for developing predictive algorithms, which are then utilised in performing multi-variate optimization on bond-slip parameters, including bond strength, bond slip and bond energy. The acquired actual and predicted findings suggest that the created models are adequate for interpreting the bond performance of reinforcement steel bars in the GO-ECC.

Engineered cementitious composite (ECC) is a fiber-reinforced cementitious composite material that has garnered considerable attention from the building and scientific sectors. However, ECCs offer improved mechanical and durability characteristics compared to regular concrete. Fibers serve a crucial function in producing ultrahigh tensile ductility and autogenous fracture width control inside the micromechanical reinforcing system of ECC. This research discusses the various proportions of polyvinyl alcohol fibers (PVA) as reinforcing materials by total volume fraction in ECC in terms of mechanical properties performance, environmental consequences, and economic effects. A total of 60 ECC samples were cast to achieve the targeted compressive strength of 45 MPa of ECC mixture reinforced with 1%, 1.5%, and 2% of PVA fiber by the volume fraction. Though, the best compressive of ECC is calculated by 62.60 MPa at 1% of PVA fiber at 28 days. Besides, the tensile and flexural strengths are enhanced by 5.20 MPa, and 11.15 MPa at 1% of PVA fiber in ECC for 28 days respectively. In addition, the density of ECC is reduced with rises in the content of PVA fiber while water absorption is increased as the percentage of PVA fiber growths in the ECC after 28 days respectively. Moreover, the embodied carbon and energy are improved when the PVA fiber by the volume fraction increases in the mixture. It has been observed that the use of 1% PVA fiber by the volume fraction in cementitious composites is offering maximum strength and less embodied carbon and energy, therefore, it has been recommended for structural application.

Industrialized construction continues to emerge globally. Developing countries like Malaysia are still unable to increase industrialized building system (IBS) implementation significantly, demonstrated by the low IBS percentage of less than 3%. Therefore, this research aims to determine the factors blocking IBS implementation through a mixed-methodological approach in the Malaysian construction industry. Using the data collected from 219 valid questionnaire responses, several statistical analyses were performed. Factor analysis was used to categorize the 25 factors into six main groups namely: “financial concerns,” “ineffective policies,” “technical and management worries,” “traditional stakeholders’ concerns,” “design restrictions” and “negative perception”. The top three critical factors are high initial capital cost, high initial cost of customized design, and transportation cost. Hence, adopting an innovative standardized design concept and increasing IBS manufacturers nationwide are recommended. The findings provide a useful guide to critical blocking factors and, thus, develop feasible solutions to achieve successful implementation of industrialized buildings.

Waste materials may be used as raw materials for interlocking masonry products in order to contribute to sustainable development and environmental protection. Rubberized concrete Interlocking Brick (RCIB) was developed by volumetric replacement of 56% of the ordinary Portland cement with fly ash and 20% of the sand with crumb rubber (CR) to reduce the production cost of conventional concrete bricks (CCB) and restrict the depletion of natural resources and contributing to solving the environmental problems associated with the accumulation of scrap tires in landfills. The mechanical and sustainability evaluation of masonry prism made of the developed brick is the aim of this research. Consequently, compressive strength, failure mechanism, stress–strain behaviour, and energy absorption of grouted and ungrouted prisms made of RCIB were measured experimentally under axial compression load. The thermal resistance, fuel consumption, CO2 emission, and cost analysis of RCIBs were estimated. The findings reveal that grout had a significant impact on the compressive strength of rubberized concrete interlocking masonry prisms where the compressive strength of grouted and ungrouted prisms was 10.99 MPa and 5.83 MPa, respectively. Web splitting and vertical cracks were the common failure modes observed in both prisms. Moreover, the rubberized concrete interlocking masonry prisms revealed greater energy absorption as well as a gradual and ductile failure mechanism. The RCIB exhibited higher thermal resistance than CCB (increased from 0.106 to 0.171 m2 K/W) which could contribute to a 62% reduction in annual fuel consumption and CO2 emission. Further, more than 25% of the material cost could be saved.

In this paper, the study and simulation of turbulent flow inside a parabolic solar collector tube equipped with two spring insert samples with two different pitch ratios (P/D = 0.22, 0.44) and a specific cross-section are investigated. Heat transfer and properties of Cu–Fe3O4/Water hybrid nanofluid with volume fractions of φ = 1%, 3%, and 5% for the range of Reynolds numbers of 7000, 9000, and 11000 are selected and investigated using the single-phase method. The tube is used as the adsorbent pipe of a parabolic solar collector to investigate the performance of the parameters such as volume fraction, Nusselt number, pressure drop, parabolic solar collector efficiency, performance evaluation criterion, and field synergy principle. The results show that with decreasing the pitch ratio, Nu and solar collector efficiency increase. The maximum efficiency is 2.53 for a tube with P/D = 0.22 (Re = 7000, φ = 1%). The maximum efficiency is obtained under the same conditions in a tube containing the spring insert with P/D = 0.44 is equal to 2.39. At the same Reynolds numbers, the average of these velocities is significantly higher than a plain tube. Field Synergy Principle is a reliable criterion to investigate the mechanism of heat transfer increase that this coefficient value in the tube equipped with a spring insert is much higher than in a plain tube. This increase indicates the positive performance of the spring insert on the heat transfer rate and solar collector efficiency improvements. Therefore, spring inserts with a lower P/D are more desirable to achieve the highest efficiency of solar collectors as a source of renewable energy.

Graphene oxide (GO) is a 2D nanoparticle with dimensions less than 100 nm and acts as nano reinforcement in cementitious composites as a filling, crack-arresting agent, and nuclei for cement hydration. GO can be utilized to improve the microstructure and mechanical properties in a variety of construction and building technology applications. Through a coherent, comprehensive mixed reviewing method, this study seeks to evaluate the research efforts on utilizing GO in cementitious composites and map the research viewpoints from available literature (bibliometric analysis and systematic review). A total of 1437 publications were screened in which 59 articles were selected upon relevancy. Bibliometric mapping is used for keyword occurrence and the tested properties of cementitious composites containing GO. The review finds that the advantage of GO as a reinforcement in cement composite is that it is more effective in controlling crack development and propagation at the nano scale level in contrast to conventional reinforcement. The use of GO in cementitious composites offers many interesting paths and provides a foundation for further optimization in concrete, mortar, engineered cementitious composites, and cement paste. On the other hand, this use has a negative influence on various features of each type of reviewed material. More research is needed to gain a better knowledge of the long-term effects of the mechanical properties and durability of GO-based cementitious composites to promote their wider use in diverse applications in the construction sector.

Engineered cementitious composite (ECC) requires a lot of material tailoring for the desired self-compacting properties at fresh state and controlled crack width with strain hardening behavior at hardened state to be attained. Finding a balance between these two important stages (fresh and hardened) of the composite without compromise on any of the desirable properties is not an easy task. This research was aimed at utilizing the technique of multi-objective optimization in trying to determine an optimal Polyvinyl alcohol (PVA) fiber volume fraction and HVFA replacement of cement (two of the most important ingredients of ECC) to develop a self-compacting HVFA-ECC (SC-HVFA-ECC) with desirable properties at both fresh and hardened stages without compromise. Using the central composite design (CCD) of RSM, 13 mixes of varying combinations of the input factors (PVA: 1–1.5 %, FA: 50–70 %) were developed on which six responses (fresh state: v-funnel time, T500 and slump flow; hardened state: compressive strength, flexural strength and tensile capacity) were investigated. Six response models (5 quadratic and 1 linear) were successfully developed and validated using ANOVA. All the models turned out to have a very high R2 value ranging from 87 to 97 %. The multi-objective optimization yielded optimal values of the variables (PVA: 1.67 % and FA: 53.61 %) and predicted optimized values for the responses. The predicted values were experimentally validated and found to compare very well with the experimental values at less than 5 % error.

Researchers have used crumb rubber in the manufacturing of engineered cementitious composites (ECC) as a solution for spalling, however, it reduces the mechanical and physical properties. Therefore, this research reviews the available and related literature reviews on rubberized ECC and its constituent. The role of each constituent in a rubberized ECC mix is also reviewed. It’s concluded that utilizing rubberized ECC helps to solve environmental issues relating to improper disposal of tyres. As a result, fly ash has been the most common substance utilized in rubberized ECC by scholars all over the world over the past years because of its encouraging impacts on rheology, matrix toughness control, and interactive effect between fiber and matrix. It’s also found that the rectification of the crumb rubber drawbacks in ECC is by incorporating a modern method of adopting nano-silica, Polyvinyl alcohol (PVA) fibers, graphene oxide into the rubberized ECC mixes. Therefore, rubberized ECC can be utilized for civil engineering applications, especially with the inclusion of nano-silica and graphene oxide, as a result of its high ductility and low permeability.

The dapped-end reinforcements of a control beam have been designed conforming to requirement of the PCI code. The dapped-end reinforcements of other beams were derived from the control beam that involve the scheme variation of the hanger or diagonal reinforcements. Some selected beams utilize the engineered cementitious composites (ECC) in the dapped-end region. Twenty-seven large-scaled beams with dapped-end have been prepared, cast and tested. All beams were tested under the three-point loading up to failure. To localize effect of the shear failure, the shear span-depth ratio (av/d) of 1.43 has been carried out. Dapped-end beam (DEB) specified in PCI code has nominal shear span-depth ratio (an/d) less than 1, but in this study, several beams use an/d larger than 1. For analytical purpose, the design equations specified in PCI code have been used for the analysis requirement. By comparing against the test results, the analysis results that using the design equations of PCI code provide a significant difference, in which the mean value of analysis-test results ratio is 0.71. The design equations specified in PCI code were reliable to design the dapped-end reinforcements, but these equations have not yet able to accommodate adequately, in analyzing and predicting the failure load of DEBs that have the dapped-end reinforcements scheme varied.

Multi-layers of carbon fibre reinforced polymer (CFRP) were used to strengthen engineered cementitious composites (ECC) to study their effects on flexural and tensile strengths. Response Surface Methodology RSM was used to obtain the number of trial mixes. A total of 13 mix designs were suggested with two variables: polyvinyl alcohol (PVA) fibre (0.5 %, 1.25 % and 2.0 %) and number of CFRP (1, 3 and 5 layers). The result showed that the flexural strength of specimens with 0.5 % and 2.0 % PVA fibre was enhanced by more than 40 % and 55 %, respectively, when the CFRP layers were increased to 3 and 5 layers, which subsequently increased the absorption energy of the specimens by more than 20 %. Moreover, the tensile strength of the specimens with 1.25 % and 2.0 % PVA fibre improved by 31 % and 61 %, respectively, after these have been strengthened with 3 and 5 CFRP layers. To validate these results, the experimental responses were analysed and optimised using RSM. The coefficient of determination R2 yielded high values at 0.9647 and 0.9747, which indicated the good agreement of the proposed model to the experimental responses. Consequently, a quadratic model and a 2FI (two-factor interaction) model were developed to estimate the bond behaviour of CFRP-strengthened ECC. Based on these models, the best solution of CFRP strengthening with respect to the present study is to use 2 % PVA fibre and 5 layers of CFRP.

The aim of this study is to evaluate the effects of inclusion nano-silica (also known as nano-SiO2) on the properties of pervious concrete containing fly ash (FA) as a partial replacement to cement. It has been found, for cementitious paste, that incorporating NS leads to reduce the cumulative pore volume by 13.4%. While the compressive strength of NS modified pervious concrete has been improved without adversely affecting its void ratio and permeability. The workability has been adversely affected by the inclusion of NS, which can be enhanced by incorporating the fly ash and superplasticizer. The porosity of cementitious paste has increased as the FA content is increased. These results are in good agreement with SEM results. For the pervious concrete voids ratio, permeability and infiltration rate were decreased against the increase of paste to the aggregate ratio Response surface methodology (RSM) has also been used to develop a model for navigating the design space of NS modified pervious concrete. Models revealed 95% significance of confidence level with difference less than 0.2 between Pred R-Squared value of 0.9515 and Adj R-Squared. The general expression has been developed for all the responses with the different coefficients using the RSM. Keywords: Fly ash, Final setting time, Infiltration rate, Pervious concrete, Nano-silica

Waste tires contribute badly to the environment on a huge scale as they are bulky, non-biodegradable, and prone to fire and being a shelter for mosquitos and other insects. This paper reports on a novel approach towards the development of rubberized brick by utilizing crumb rubber as the sole fine aggregate in the production of geopolymer interlocking bricks. The response surface methodology (RSM) from Design Experts software has been used to determine the numbers of trial mixes and their corresponding ingredients. A total of thirteen trial mixes were carried out and tested for compressive strength and the RSM model was developed to predict the design mix based on the targeted compressive strength. The mix design was obtained to be an 18 M for NaOH and 0.8 solution to fly ash ratio. The geopolymer interlocking rubberized bricks were then produced and tested for compressive strength, dimension, modulus of rupture, water absorption, initial rate of absorption, and efflorescence. The geopolymer interlocking rubberised bricks presented a low compressive and flexural strength and a high-water absorption capacity. The bricks were rated as non-effloresced and classified as 3rd class bricks which can be used as non-load bearing material. It is recommended to utilize nano silica in order to increase the strength of the brick. Keywords: Rubberized bricks, Crumb rubber, Interlocking bricks, Geopolymer, Response surface methodology

The major problems related to roller compacted concrete (RCC) pavement are high rigidity, lower tensile strength which causes a tendency of cracking due to thermal or plastic shrinkage, flexural and fatigue loads. Furthermore, RCC pavement does not support the use of dowel bars or reinforcement due to the way it is placed and compacted, these also aided in cracking and consequently increased maintenance cost. To address these issues, high volume fly ash (HVFA) RCC pavement was developed by partially replacing 50% cement by volume with fly ash. Crumb rubber was used as a partial replacement to fine aggregate in HVFA RCC pavement at 0%, 10%, 20%, and 30% replacement by volume. Nano silica was added at 0%, 1%, 2% and 3% by weight of cementitious materials to improve early strength development in HVFA RCC pavement and mitigate the loss of strength due to the incorporation of crumb rubber. The nondestructive technique using the rebound hammer test (RHT) and ultrasonic pulse velocity (UPV) were used to evaluate the effect of crumb rubber and nano silica on the performance of HVFA RCC pavement. The results showed that the use of HVFA as cement replacement decreases both the unit weight, compressive strength, rebound number (RN). Furthermore, the unit weight, compressive strength, RN, UPV and dynamic modulus of elasticity of HVFA RCC pavement all decreases with increase in crumb rubber content and increases with the addition of nano-silica. Combined UPV-RN (SonReb) models for predicting the 28 days strength of HVFA RCC pavement based on combining UPV and RN were developed using multivariable regression (double power, bilinear, and double exponential models). The exponential combined SonReb model is the most suitable for predicting the compressive strength of HVFA RCC pavement using UPV and RN as the independent variable with better predicting ability, higher correlation compared to the single variable models. Keywords: Crumb rubber, High volume fly ash, Nano silica, Roller compacted concrete pavement, Ultrasonic pulse velocity, Rebound number

Since the mid-2000s, the transformation for the advanced 21st-century construction material has been on a headway utilizing the cutting-edge nanomaterials includes nano-silica, Carbon Nanotubes (CNTs), and Graphene Oxide (GO). GO is a recently invented only 2D carbon-based nanomaterial as it provides an additional dimension for the reactivity with cement composites. GO is an irresistible nanomaterial as it reforms the cement composite ranging from the atomic scale to macroscale and strengthens the mechanical properties (viz., compressive strength, tensile strength, flexural strength, and Young's modulus), durability and other multifunctional behavior. The availability of larger surface area and various oxygen-based functional groups form a linkage and contributes to the impressive behavior of the cementitious matrix. This research article presents a comprehensive review of the performance and behavior of cementitious composites tailored with GO nanomaterial.

In this present experimental study, geopolymer cement is developed using high calcium fly ash and used in the production of one-part alkali-activated binders. At 8–16 percent of the total precursor materials, the HCFA was activated with anhydrous sodium metasilicate powder and cured in ambient condition. Five mixtures of one-part geopolymer paste were intended at a steady w/b proportion. Density, flowability, setting time, compressive strength, splitting tensile strength and molar ratio impact were envisaged. It was observed that the setting time of the designed one-part geopolymer paste decreases with higher activator content. The experimental findings showed that the resistance of one-part geopolymer cement paste increases with comparatively greater activator content. However, raising the granular activator beyond 12 percent by fly ash weight decreases the strength and workability of the established one-part geopolymer cement. The optimum mix by weight of the fly ash was discovered to be 12 percent (i.e. 6 percent Na2O). At 28 days of curing, one-part alkali-activated paste recorded the greatest compressive strength of almost 50 MPa. The density of the one-part geopolymer paste is nearly the same regardless of the mixes. Microstructural assessment by FESEM, FTIR and XRD has shown that the established geopolymer paste includes quartz, pyrrhotite, aluminosilicate sodium and hydrate gels of calcium aluminosilicate. Based on the experimental information acquired, it can be deduced that the strength growth of one-part geopolymer cement is similar to that of Portland cement.

Wastewater treatment plants play a vital role in resource recovery, particularly through biogas production, a key renewable energy source. Beyond biogas, the digestate from anaerobic digestion is rich in nutrients like ammonia. This study explored the feasibility of recovering ammonia from sewage sludge digestate using air stripping. The process was modeled using Aspen Plus® software, utilizing real data from As-Samra WWTP in Jordan. Various operational parameters, such as digestate feed flow, air flow rate, temperature, and pressure, were analyzed to optimize ammonia recovery. The results showed that with a feed flow rate between 10,000 and 30,000 kg/hr, ammonia recovery reached 85%, with production exceeding 100 kg/hr, where the effect of the flow rate appears mostly at elevated feeding temperatures. Increased air flow rates significantly boosted recovery, achieving 90% efficiency at 60 °C with 50,000 kg/h as air flow. Flashing pressure peaked at 1.5 bar, with 85% efficiency at 95 °C, while higher pressures yielded diminishing returns, stabilizing production around 106 kg/hr. The NaOH feed rate also influenced output, rising from 100 kg/hr at a 50 kg/hr feed rate to 107 kg/hr at 750 kg/hr, with recovery efficiency exceeding 85%. The economic analysis showed that the project had a payback period of 6.07 years, reflecting a reasonable recovery of the initial investment. The net present value was 122,924 USD over 15 years, with 8% amortization rate, indicating that the project created value beyond the initial cost. The internal rate of return was 14.23%, surpassing the discount rate and highlighting the project's financial attractiveness.

Building integrated photovoltaic thermal (BIPV/T) systems offer a highly effective means of generating clean energy for both electricity and heating purposes in residential buildings. Hence, this article introduces a new BIPV/T system to optimally minimize the energy consumption of a household residential building. The meticulous design of the proposed BIPV/T system is accomplished through MATLAB/Simulink® dynamic modeling. Performance analysis for the BIPV/T system is performed under different seasonal conditions with in-depth techno-economic analyses to estimate the expected enhancement in the thermal, electrical, and economic performance of the system. Moreover, a sensitivity analysis is conducted to explore the impact of various factors on the energetic and economic performances of the proposed BIPV/T system. More so, the two-layer feed-forward back-propagation artificial neural network modeling is developed to accurately predict the hourly solar radiation and ambient temperature for the BIPV/T. Additionally, a multi-objective optimization using the NSGA-II method is also conducted for the minimization of the total BIPV/T plant area and maximization of the total efficiency and net thermal power of the system as well as to estimate the optimized operating conditions for input variables across different seasons within the provided ranges. The sensitivity analysis revealed that higher solar flux levels lead to increased electric output power of the BIPV/T plant, but total efficiency decreases due to higher thermal losses. Moreover, the proposed NSGA-II shows a feasible method to attain a maximum net thermal power and optimal total efficiency of 5320 W and 63% with a minimal total plant area of 32.89 m2 that attained a very low deviation index from the ideal solution. The levelised cost of electricity is obtained as 0.10 $/kWh under the optimal conditions. Thus, these findings offer valuable insights into the potential of BIPV/T systems as a sustainable and efficient energy solution for residential applications.

To meet the required load of a farm in the rural area in Mafraq, Jordan, the complete floating photovoltaic (FPV) water pumping sizing, modelling, and optimization of an on-grid PV system with comprehensive capacity, energy output cost, and emission estimations are outlined in this work. The novelty of this study lies in its comprehensive approach that integrates technical, environmental, and economic factors into a unified framework for designing a PV water pumping system, particularly in scenarios where grid supply is feasible or economically viable. A proposal has been made to install PV panels over the water lake to improve the overall system efficiency and to give an aesthetic appearance. The proposed system is composed of a 165 kW PV array and three 55 kW inverters, which cost 54696.92 JD as the initial cost, CO2 emission reduction of more than 5000 tons and produce electricity at 0.028 JD/kWh. The results indicated that the FPV option demonstrates an about 5 % increase in efficiency compared to the other two scenarios. Also, the FPV option has higher costs due to a 25 % increase in system cost but results in lower CO2 emissions compared to the other two options. Top of Form As shown from the results, the two sizing methods for solar water pumping systems, the equations-based method, and the PVsyst simulation tool give the same results. By following this methodology, one can assess the load, size the system, simulate its operation, and analyse the expected performance. Furthermore, the findings of this study could be valuable in designing a grid-connected FPV water pumping system.

Background: Total neoadjuvant therapy (TNT) is an accepted approach for the management of locally advanced rectal cancer (LARC) and is associated with a decreased risk of development of metastatic disease compared to standard neoadjuvant therapy. However, questions remain regarding surgical outcomes and local control in patients who proceed to surgery, particularly when radiation is given first in the neoadjuvant sequence. We report on our institution's experience with patients who underwent short-course radiation therapy, consolidation chemotherapy, and surgery. Methods: We retrospectively reviewed surgical specimen outcomes, postoperative complications, and local/pelvic control in a large cohort of patients with LARC who underwent neoadjuvant therapy incorporating upfront short-course radiation therapy followed by consolidation chemotherapy. Results: In our cohort of 83 patients who proceeded to surgery, a complete/near-complete mesorectal specimen was achieved in 90 % of patients. This outcome was not associated with the time interval from completion of radiation to surgery. Postoperative complications were acceptably low. Local control at two years was 93.4 % for all patients- 97.6 % for those with low-risk disease and 90.4 % for high-risk disease. Conclusion: Upfront short-course radiation therapy and consolidation chemotherapy is an effective treatment course. Extended interval from completion of short-course radiation therapy did not impact surgical specimen quality.

Incorporating distributed renewable energy sources into heating, power, and cooling systems is facilitating the drive toward intelligent building energy solutions. However, the inherent uncertainties associated with controllable renewable resources pose challenges for the thermo-economic scheduling of smart buildings. Nonetheless, the flexibility inherent in smart buildings can be leveraged through various market mechanisms. Hence, this research introduces a sustainable energy-building system driven by an autonomous solar/dish Stirling engine (SDSE) and wind turbine combined with a sophisticated control strategy and battery storage, which is designed to provide heat and power requirements. The proposed control strategy is also devised to optimize energy generation, ensuring prudent conservation and minimal waste, thereby amplifying overall efficiency and financial viability. The meticulous design of the system is accomplished through advanced MATLAB/Simulink® modeling. A thorough technical sensitivity analysis meticulously hones design parameters, revealing optimal operational thresholds. Simulation outcomes unveil a consistent Stirling engine (SE) efficiency, achieving a pinnacle of 35 %, while the SDSE attains over 28 %, respectively. The horizontal axis wind turbine, encompassing 100 kW and 500 kW modules, demonstrates power coefficients spanning from 0.18 to 0.09, with corresponding land area requirements ranging from 4.22 m2 to 21.10 m2, emphasizing the pivotal roles of module power and land area optimization. This paper also casts a spotlight on the environmental repercussions of the system, illustrating its potential to avert up to 30,000 kg of CO2 emissions per kWh/year. Moreover, the levelized cost of electricity ranges from 0.13 to 0.16 $/kWh, accompanied by an hourly cost that fluctuates between 3 $/h and 40 $/h, respectively. Conclusively, the developed modeling can be regarded as a significant stride in the realm of hybrid renewable energy systems, replacing the conventional photovoltaic/wind models with cutting-edge solar/wind configurations managed by a sophisticated control strategy and battery storage system.

This article outlines the input data and partial shading conditions employed in the replication model of Sequential Monte Carlo (SMC)-based tracking techniques for photovoltaic (PV) systems. The model aims to compare the performance of classical perturb and observe (P&O) algorithm, particle swarm optimization (PSO) algorithm, flower pollination algorithm (FPA), and SMC-based tracking techniques. The mathematical design and methodology of the complete PV system were detailed in our prior research, titled ''Dynamic and Adaptive Maximum Power Point Tracking Using Sequential Monte Carlo Algorithm for Photovoltaic System'' by Odat et al. (2023) [1]. The provided data facilitate precise replication of the output, saving significant simulation time. Additionally, these data can be readily applied to compare algorithmic results referenced by (Babu, T.S. et al., 2015; PrasanthRam, J. et al., 2017) [2,3], and contribute to the development of new processes for practical applications.

The hike in fuel prices and rapid depletion of fuel reserves have compelled scientists to focus on energy conservation, environmental protection, engine performance improvement, and cost saving. The prime objective of the study is to compare the empirical results with response surface methodology (RSM) optimized results in order to check the accuracy of model designed by RSM. Therefore, the current study examines the effect of fuel injection parameters (nozzle opening pressure and protrusion) on diesel engine performance and exhaust emissions. RSM technique was applied to predict engine performance and exhaust emission parameters along with their optimization. The brake thermal efficiency (BTE) was incremented by 1.23 % for protrusion from 1.5 to 2.5 mm under 240 bar nozzle opening pressure (NOP). BTE was increased by 0.94 and 4.51 % for 1.5 and 2.5 mm protrusion respectively. CO emission was decremented by 4.47 and 11.31 % for 1.5 and 2.5 mm protrusion respectively when the NOP changed from 230 to 240 bar. RSM model optimized input conditions 240 bar pressure, 2.5 mm protrusion, and 1935.67 engine rpm. The engine was again tested on RSM-optimized conditions and the highest absolute percentage error (APE) of 4.42 % was obtained for NOx emission, while the lowest APE of 2.89 % was obtained for BSFC.

Background and Aims: Adalimumab (ADA) transport across the placenta increases with gestational age advances. We evaluated child–mother health outcomes related to the timing of the last ADA dose before delivery. Methods: Using IBM MarketScan data, we collected records for all children exposed to ADA during intrauterine life. We compared milestone achievements, congenital malformations, and respiratory infections rates in children from mothers of 2 groups: (1) a late ADA group, which continued therapy until 90 days or fewer before delivery; and (2) an early ADA group, which discontinued therapy more than 90 days before delivery. We also assessed the risk of flaring for mothers in the early group. Results: There were no significant differences in growth (P = .48), developmental delays (P = .25), or congenital malformations (P = .61) in the 427 children of the late group vs 70 children of early ADA group. Continuing ADA late in pregnancy did not increase the respiratory infection rate (P = .38). No differences occurred between groups in cesarean and premature delivery, intrauterine growth retardation, and stillbirths. ADA discontinuation was the only predictor of flaring in the third trimester of pregnancy (odds ratio = 6.04, 95% confidence interval 2.66–13.7). In the late group, mothers’ risk of flaring decreased (16/447 vs 13/73, P < .001). Mothers with active disease were more likely to deliver prematurely vs mothers with quiet disease (6/29 vs 31/491, P = .003). Conclusion: Continuation of ADA in pregnancy close to delivery is of low risk for children. Early discontinuation, however, increases the risk of flaring in mothers and the likelihood of premature deliveries.

Background: Despite anti-retroviral therapy, HIV-1 infection increases the risk of pneumonia and causes oxidative stress and defective alveolar macrophage (AM) immune function. We have previously determined that HIV-1 proteins inhibit antioxidant defenses and impair AM phagocytosis by suppressing nuclear factor (erythroid-derived 2)-like 2 (Nrf2). Given its known effects on Nrf2, we hypothesize miR-144 mediates the HIV-1 induced suppression of Nrf2., Methods: Primary AMs isolated from HIV-1 transgenic (HIV-1 Tg) rats and wild type littermates (WT) as well as human monocyte-derived macrophages (MDMs) infected ex vivo with HIV-1 were used. We modulated miR-144 expression using a miR-144 mimic or an inhibitor to assay its effects on Nrf2/ARE activity and AM functions in vitro and in vivo., Results: MiR-144 expression was increased in AMs from HIV-1 Tg rats and in HIV-1-infected human MDMs compared to cells from WT rats and non-infected human MDMs, respectively. Increasing miR-144 with a miR-144 mimic inhibited the expression of Nrf2 and its downstream effectors in WT rat macrophages and consequently impaired their bacterial phagocytic capacity and H 2 O 2 scavenging ability. These effects on Nrf2 expression and AM function were reversed by antagonizing miR-144 ex vivo or in the airways of HIV-1 Tg rats in vivo, but this protection was abrogated by silencing Nrf2 expression., Conclusions: Our results suggest that inhibiting miR-144 or interfering with its deleterious effects on Nrf2 attenuates HIV-1-mediated AM immune dysfunction and improves lung health in individuals with HIV., (Copyright © 2020 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.)

Background: Alcohol significantly impairs antioxidant defenses and innate immune function in the lung and increases matrix metalloproteinase 9 (MMP-9) activity. The receptor for advanced glycation end products (RAGE) is a well-characterized marker of lung injury that is cleaved by MMP-9 into soluble RAGE and has not yet been examined in the alcoholic lung. We hypothesized that chronic alcohol ingestion would impair RAGE signaling via MMP-9 in the alveolar macrophage and thereby impair innate immune function., Materials and Methods: Primary alveolar macrophages were isolated from control-fed or alcohol-fed rats. Real-time polymerase chain reaction (qRT-PCR), Western blotting, and enzyme-linked immunosorbent assays were performed to evaluate RAGE expression. Silencing of MMP-9 ribonucleic acid (RNA) in a rat alveolar macrophage cell line was confirmed by qRT-PCR, and immunofluorescence (IF) was used to assess the association between alcohol, MMP-9, and RAGE. Phagocytosis was assessed using flow cytometry. Sulforaphane and glutathione were used to assess the relationship between oxidative stress and RAGE., Results: RAGE messenger RNA expression was significantly increased in the alveolar macrophages of alcohol-fed rats, but IF showed that membrane-bound RAGE protein expression was decreased. Lavage fluid demonstrated increased levels of soluble RAGE (sRAGE). Decreasing MMP-9 expression using si-MMP-9 abrogated the effects of alcohol on RAGE protein. Phagocytic function was suppressed by direct RAGE inhibition, and the impairment was reversed by antioxidant treatment., Conclusions: Chronic alcohol ingestion reduces RAGE protein expression and increases the amount of sRAGE in alveolar lavage fluid, likely via cleavage by MMP-9. In addition, it impairs phagocytic function. Antioxidants restore membrane-bound RAGE and phagocytic function., (Copyright © 2017 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.)