Knowledge and practice of protective personal equipment (PPE) among health care providers in Saudi Arabia during the early stages of COVID-19 Pandemic in 2020

Introduction. Health care providers are at high risk of becoming infected when taking care of patients who have COVID-19, especially while attending aerosol generating procedures. Protective personal equipment must be used in the correct manner to prevent transmission of the disease. Published protocols on protective personal equipment (PPE) donning and doffing have been issued by disease control agencies. Methods. A questionnaire-based cross-sectional study was designed. An online anonymous questionnaire, which was validated and tested for reliability, focused on PPE related knowledge, donning and doffing practices of healthcare providers across the eastern region of Saudi Arabia. Results. A total of 312 healthcare providers across the eastern region of Saudi Arabia participated in the study, 208 physicians (66.7%) and 104 non-physicians (33.3%). Results indicate poor practice regarding PPE donning (13.8% reported the correct sequence) and PPE doffing (3.5% reported the correct sequence) among participants. In addition, practice and confidence scores regarding other issues with PPE were analyzed. Based on questionnaire responses, being male (T=2.825; p=0.008), being a non-physician (T=-2.120; p=0.014) and being an allied medical professional (F=5.379; p=0.003) were significantly associated with higher confidence levels. Also, being a consultant was significantly associated with higher practice scores (F=4.774; p=0.008). Conclusion. The study demonstrates deficiencies among healthcare providers in following the recommended practices for correctly using PPE during the pandemic. Poor practice in PPE donning and doffing necessitates additional educational and training programs focused on infection control practices

Modeling of lead (II) ion adsorption on multiwall carbon nanotubes using artificial neural network and Monte Carlo technique

In this study, Pb2+ removal from wastewater using multiwall carbon nanotubes (MWCNTs) was investigated. XRD, SEM-EDX, BET, and FTIR were employed for MWCNT characterization. The effects of various parameters, including the solution pH, adsorbent dosage, initial concentration of Pb2+, and contact time, on the Pb2+ removal from wastewater were investigated experimentally. Furthermore, the nonlinear relationship among the parameters was predicted using an artificial neural network (ANN) approach. The Levenberg–Marquardt training algorithm showed the best training performance, with a mean-square error of 2.200× 10−5 and an R2 of 0.998. Combining the ANN models and Monte Carlo simulation, Pb2+ removal efficiency of 99.8% was obtained under the optimum conditions (pH of 10, MWCNT dosage of 0.05 g, contact duration of 60 min, and Pb2+ concentration of 100 mg/L). The high removal efficiency can be attributed to the available adsorption sites (active sites). The results of the reusability of MWCNTs showed that the adsorption efficiency was higher than 90%. Thus, MWCNTs have great potential for recycling and managing Pb2+ from wastewater

Preventive Maintenance Scheduling for Multicogeneration Plants with Production Constraints Using Genetic Algorithms

This paper describes a method developed to schedule the preventive maintenance tasks of the generation and desalination units in separate and linked cogeneration plants provided that all the necessary maintenance and production constraints are satisfied. The proposed methodology is used to generate two preventing maintenance schedules, one for electricity and the other for distiller. Two types of crossover operators were adopted, 2-point and 4-point. The objective function of the model is to maximize the available number of operational units in each plant. The results obtained were satisfying the problem parameters. However, 4-point slightly produce better solution than 2-point ones for both electricity and water distiller. The performance as well as the effectiveness of the genetic algorithm in solving preventive maintenance scheduling is applied and tested on a real system of 21 units for electricity and 21 units for water. The results presented here show a great potential for utility applications for effective energy management over a time horizon of 52 weeks. The model presented is an effective decision tool that optimizes the solution of the maintenance scheduling problem for cogeneration plants under maintenance and production constraints

Investigating the Impact of Integration the Saudi Code of Energy Conservation with the Solar PV Systems in Residential Buildings

The demand for air conditioning is increasing day by day in the world’s hot and humid climate areas. Energy conservation in buildings can play a vital role in meeting this high cooling demand. This paper attempts to consider the impacts of energy efficiency and renewable energy measures on the energy demand of Saudi Arabia’s residential buildings. The energy analysis and economic feasibility analysis of thermal insulations are performed in this paper by investigating the effect of residential buildings’ thermal insulations on the economic feasibility of grid-connected photovoltaic systems. This was the combined effort of building owners and government, and buildings were examined if a photovoltaic system and thermal insulation were used. The study was conducted in the three climate zones in Saudi Arabia. The results showed that the building base case’s annual electrical energy consumption in Riyadh city was 67,095 kWh, Hail 57,373 kWh, and Abha 26,799 kWh. For the basic case-building in Riyadh, 69% of the total electrical energy was used for cooling and heating. Applying the Saudi Building Code requirement for Riyadh will provide only 18% of the total energy used for cooling and heating. RETScreen 6.1 software was used to design a photovoltaic system; the analysis was done using technical and economic indicators. The annual yield factor for Riyadh, Hail, and Abha was 1649 kWh/kWp/year, 1711 kWh/kWp/year, and 1765 kWh/kWp/year, respectively. The capacity factors for Riyadh, Hail, and Abha were 18.8%, 19.5%, and 20.1%, respectively. The Unified photovoltaic Levelized energy costs were 0.031, 0.030, and 0.029 $/kWh for Riyadh, Hail, and Abha, respectively. Finally, the Net Present Value and greenhouse gas emissions reduction have been estimated

Assessing the Crashworthiness Analysis on Frontal and Corner Impacts of Vehicle on Street Poles Using FEA

The impact analysis of vehicle collision on street poles was investigated, as well as an assessment of which type of impact—frontal or corner—contributes to the most damages on both the car and the streetlamp. This work was accomplished using Abaqus/Explicit software to numerically simulate the crashes at three different velocities, 12, 17, and 22 m·s−1, and extract relations such as the energy models, the specific energy absorption (SEA) of the materials tested, and the impact forces. Two materials were used for the street pole: aluminum Al-6061 and ASTM A36 grade steel. Findings such as the influence of the SEA on the vehicle’s velocity, the relationship between the deformation of the street pole and the vehicle’s velocity, as well as the improvement of previously studied models by including damage parameters are presented

Crashworthiness Analysis to Evaluate the Performance of TDM-Shielded Street Poles Using FEA

The mitigation of the risks of passenger injuries when a vehicle is involved in a collision with a street pole shielded with a layer of tire-derived material (TDM) was assessed. This can effectively absorb a fraction of the total energy from a speeding vehicle. Since such tests are expensive to conduct experimentally, the study relies on using the Abaqus/Explicit FEA solver to accurately calculate the non-linear nature of this scenario. Two categories of this scenario were evaluated to understand the effect a shielded street pole has on the vehicle—and the total absorbed energies during frontal and corner collisions, which are typically the most common categories of such accidents to happen. Results show that at lower speeds, these reinforcements are least effective in absorbing some of the kinetic energy applied by the vehicle, with about 5% of the energy absorbed by the reinforcement. At higher speeds, however, the results show that the TDM reinforcement absorbs about 28% of kinetic energy, which can reduce injury of the vehicle occupants, as well as decrease the damage on poles. Results for this simulation also show that there is a critical thickness of TDM that can absorb these kinetic energies, after which further thicknesses results in energies being applied back to the vehicle, therefore negating any purpose to further increase TDM thicknesses

Contaminants Removal from Real Refinery Wastewater Associated with Energy Generation in Microbial Fuel Cell

Microbial fuel cells (MFCs) pertain to a kind of modern technology for the direct conversion of chemical energy in organic matter from wastewaters into electricity during the oxidation of organic substrates. A system of continuous MFC was constructed for the treatment of real petroleum refinery wastewater (PRW). The treatment of real PRW, operational performance of the MFC system, biodegradation of furfural, and energy output were investigated in this study. The MFC was inoculated by mixed anaerobic bacteria, with Bacillus sp. as the dominant type, and continuously operated for 30 days. The biodegradation of furfural and phenol, which are the most prevalent toxicants in refinery wastewater, was investigated. The MFC system reached maximum energy outputs of 552.25 mW/m3 and 235 mV. In the anodic chamber, the maximum removal of furfural and phenol was higher than 99%, with biodegradation of organic content reaching up to 95%. This study demonstrated the viability of a continuous-flow MFC system as a green technology for the treatment of furfural-rich real refinery effluents while generating electricity