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"Farouk, Mohamed"
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Controlling Seepage Flow Beneath Hydraulic Structures: Effects of Floor Openings and Sheet Pile Wall Cracks
Using one opening (filter) within the floors of hydraulic structures is a known technique to relieve the seepage effects on their floors. In this study, a new method to control seepage flow by using two identical filters instead of one was tackled numerically. A comparative analysis of using one versus two filters was conducted for different thicknesses of the permeable stratum, apron size (b), filter length, and sheet pile wall depths. Results indicate that two filters are considerably more effective than using one where the overall uplift force, the maximum potential head, and the hydraulic exit gradient downstream of the floor are reduced to 42–56%, 42–51%, and 66–76%, respectively, compared to one filter, while slightly increasing seepage flow by 1–7%. Many reasons can lead to horizontal openings (cracks) appearing along the sheet pile walls beneath hydraulic structures. The current study tackled their effects on seepage flow for the first time and examined their impact on the floor. A crack in the upstream sheet pile wall can increase total uplift forces by up to 40%, while a crack in the downstream sheet pile wall can increase the hydraulic exit gradient by up to 230%
Journal Article
Structural and Environmental Safety Studies of the Holy Mosque Area Using CFD
A three-dimensional (3D) CFD model was developed, covering a square area of 3.64 km2 and comprising the Holy Mosque near its center, the actual terrain, and the main surrounding buildings. The gust wind effects on the existing cranes and the collapsed tower crane in 2015, the comfort of the pedestrians, and the air quality were studied for the first time in this area. The air quality was related to calm speed, accelerating the spreading of infectious diseases. The wind comfort levels were achieved in all selected locations. The wind speeds are generally low in the area. However, gusting wind currents appeared from limited directions, causing increments in wind speeds up to 30% and causing the tower crane to collapse. Therefore, finalizing work on some cranes is recommended soon, lowering the crane boom and stopping working on windy days or changing their places. The air quality in some sites may be relatively poor, such as at the lower terraces level. New tall buildings surrounding the mosque from the north and the east are not recommended unless studying their impacts on the air quality. Pruning north and east mounts can remarkably improve natural ventilation. Large-scale fans are another solution after a detailed simulation study.
Journal Article
Optimizing human thermal comfort and mitigating the urban heat island effect on public open spaces in Rome, Italy through sustainable design strategies
The climate affects how a city’s outdoor spaces are utilized. It is more likely that people will use and appreciate public areas designed for pedestrian use, such as parks, squares, streets, and foot-cycle pathways, when they provide a comfortable and healthy environment. A predicted increase in global temperature has made the climate uncomfortable, especially during the summer when heat stress is strengthened and anticipated. This phenomenon is more severe in urban areas, often affected by the Urban Heat Island (UHI) effect. Since the spatial characteristics of a city influence its climate, urban design can be deployed to mitigate the combined effects of climate change and UHI. This research is conducted to study the UHI effect on thermal comfort in an urban open space in Rome (Italy) and aims at identifying and implementing a methodology that urban designers can follow to reduce the impact of urban heat islands and increase thermal comfort in urban outdoor space. This study is based on an urban design concept adopting the Sustainable Development Goals as guidelines; it investigates how UHI’s effect affects the use of public space and examines the influence of urban microclimatic conditions on the thermal perception of users through PET, PMV and PPD values, that were assessed through simulations with ENVI-MET software. The study thus proposes a redesign for the site in Rome, with a masterplan based on sustainable design principles, aimed at improving the microclimatic conditions in the site. The design solution was then validated through ex post simulations.
Journal Article
Appraisal of Surface Water Quality of Nile River Using Water Quality Indices, Spectral Signature and Multivariate Modeling
Surface water quality management is an important facet of the effort to meet increasing demand for water. For that purpose, water quality must be monitored and assessed via the use of innovative techniques, such as water quality indices (WQIs), spectral reflectance indices (SRIs), and multivariate modeling. Throughout the Rosetta and Damietta branches of the Nile River, water samples were collected, and WQIs were assessed at 51 different distinct locations. The drinking water quality index (DWQI), metal index (MI), pollution index (PI), turbidity (Turb.) and total suspended solids (TSS) were assessed to estimate water quality status. Twenty-three physicochemical parameters were examined using standard analytical procedures. The average values of ions and metals exhibited the following sequences: Ca2+ > Na2+ > Mg2+ > K+, HCO32− > Cl− > SO42− > NO3− > CO3− and Al > Fe > Mn > Ba > Ni > Zn > Mo > Cr > Cr, respectively. Furthermore, under the stress of evaporation and the reverse ion exchange process, the main hydrochemical facies were Ca-HCO3 and mixed Ca-Mg-Cl-SO4. The DWQI values of the two Nile branches revealed that 53% of samples varied from excellent to good water, 43% of samples varied from poor to very poor water, and 4% of samples were unsuitable for drinking. In addition, the results showed that the new SRIs extracted from VIS and NIR region exhibited strong relationships with DWQI and MI and moderate to strong relationships with Turb. and TSS for each branch of the Nile River and their combination. The values of the R2 relationships between the new SRIs and WQIs varied from 0.65 to 0.82, 0.64 to 0.83, 0.41 to 0.60 and 0.35 to 0.79 for DWQI, MI, Turb. and TSS, respectively. The PLSR model produced a more accurate assessment of DWQI and MI based on values of R2 and slope than other indices. Furthermore, the partial least squares regression model (PLSR) generated accurate predictions for DWQI and MI of the Rosetta branch in the Val. datasets with an R2 of 0.82 and 0.79, respectively, and for DWQI and MI of the Damietta branch with an R2 of 0.93 and 0.78, respectively. Therefore, the combination of WQIs, SRIs, PLSR and GIS approaches are effective and give us a clear picture for assessing the suitability of surface water for drinking and its controlling factors.
Journal Article
Relation between vitamin D deficiency and benign paroxysmal positional vertigo
Benign paroxysmal positional vertigo (BPPV) is the most common cause of positional vertigo. Vitamin D deficiency may be one of the causes of its development. To assess the relation between recurrent attacks BPPV and Vitamin D deficiency. A case control study in which 40 patients were clinically diagnosed as posterior canal BPPV, Serum 25(OH) D was measured at 1st visit. Patients were divided into two groups; group A (20 patients) received Vitamin D supplementation in addition to canal repositioning maneuver and group B (20 patients) treated by canal repositioning maneuver only. Follow up of all patients for 6 months, neuro-otological assessment was repeated and recurrent attacks were recorded. Serum vitamin D was repeated after 6 month. This study included 14 males and 26 females age ranged from 35 to 61 years, Average serum of 25 (OH) D at the first visit was (12.4 ± 2 ng/ml) for group A, and (12.2 ± 1.7 ng/ml) for group B, all patients had low serum level of 25(OH) D (below 20 ng/ml). Recurrent BPPV episodes, were significantly lower in group A than that of group B. There is a relation between BPPV recurrence and low serum Vitamin D.
Journal Article
Physical activity and its associated factors in females with type 2 diabetes in Riyadh, Saudi Arabia
Despite the benefits of physical activity (PA) for the management of type 2 diabetes Mellitus (T2DM), the topic of PA is poorly addressed in Saudi Arabia (SA), especially in females with T2DM. The present study examined PA and its associated factors in females with T2DM in Riyadh, Saudi Arabia. This observational cross-sectional study was performed in a random sample of 372 women with T2DM. A face-to-face interview that covered PA, health and environmental correlates of PA was performed. Discriminant analysis was used to determine which barriers had the greatest impact on PA in these women. The results showed that approximately 26.3% of the study participants met PA recommendations. Multivariate linear regression revealed lower levels of PA were associated with women who had more than three children ([beta] = -0.17) compared to women with no children, older age ([beta] = -0.18), women with a duration of diabetes [greater than or equal to] 6 years ([beta] = -0.16), women who were obese ([beta] = -0.23), women with no family support ([beta] = -0.20), no friend support ([beta] = -0.13) and no healthcare provider support ([beta] = -0.14). Discriminant analysis indicated that culture and tradition, lack of skills and knowledge, safety, fatigue, lack of time, weather conditions, and lack of facilities were the barriers that differentiated between the women who met and those who did not meet the PA recommendations. The present study suggests that the prevalence of PA is low and number of children, age, duration of diabetes, Obesity, family support, friend support and healthcare provider support are identified correlates of PA. These findings are valuable and should be used to design and implement future PA interventions, especially for women with T2DM. Healthcare providers may improve exercise levels and identify the specific barriers to reaching the recommended level of PA to improve health outcomes for each patient.
Journal Article
Generative design optimization of tree distribution for enhanced thermal comfort in communal spaces with special reference to hot arid climates
The quality of the communal outdoor environment is crucial for enhancing the urban quality and the well-being of its residents. These spaces are essential for providing more opportunities for social interaction and leisure. However, in hot arid climates like Egypt, achieving optimal outdoor thermal comfort remains a challenge. Accordingly, more comprehensive methodologies are highly needed to improve the research-based design of landscape parameters and components for developing outdoor thermal comfort performance using an iterative design exploration process that employs AI-driven software. These applications, help designers in solving multi-objective design quandaries through the generation and evaluation of numerous design options. Therefore, this study explores the efficiency of generative design tools in optimizing tree distribution based on mutation evolution to enhance outdoor thermal comfort, providing a dynamic, iterative approach that adapts to diverse urban morphologies. The methodology adopts a simulation-based analysis for framing this study, which is classified into three main phases. Firstly, analyze the current environment for specific outdoor spaces with different settings in Madinaty, New Cairo (fully clustered with buildings neighborhood, semi-clustered neighborhood, fully open neighborhood). Secondly, a generative design tool with a Dynamo evolutionary algorithm is utilized to optimize the tree distribution across the communal areas of these three spaces considering the current built environment. Lastly, testing thermal comfort using Grasshopper and Ladybug simulation to assess the Universal Thermal Climate Index (UTCI) between the base case scenarios and the optimized scenarios to validate the generative design tool. Results indicate tangible improvements across the three different neighborhoods. In the Clustered Neighborhood area, the optimized design with 33 trees resulted in a lower UTCI (with an arithmetic mean of 37.55 °C) compared to the base case with 43 trees (38 °C). In the Semi-Clustered Neighborhood area, the optimized design with 45 trees highly improves the UTCI (38.01 °C), compared with the base case with 27 trees (39.40 °C). Lastly, for the Fully Open Neighborhood area, the optimized design with 25 trees achieved a slightly improved UTCI (39.55 °C) over the base case of 31 trees (39.60 °C).
Journal Article
Data reduction for SVM training using density-based border identification
Numerous classification and regression problems have extensively used Support Vector Machines (SVMs). However, the SVM approach is less practical for large datasets because of its processing cost. This is primarily due to the requirement of optimizing a quadratic programming problem to determine the decision boundary during training. As a result, methods for selecting data instances that have a better likelihood of being chosen as support vectors by the SVM algorithm have been developed to help minimize the bulk of training data. This paper presents a density-based method, called Density-based Border Identification (DBI), in addition to four different variations of the method, for the lessening of the SVM training data through the extraction of a layer of border instances. For higher-dimensional datasets, the extraction is performed on lower-dimensional embeddings obtained by Uniform Manifold Approximation and Projection (UMAP), and the resulting subset can be repetitively used for SVM training in higher dimensions. Experimental findings on different datasets, such as Banana, USPS, and Adult9a, have shown that the best-performing variations of the proposed method effectively reduced the size of the training data and achieved acceptable training and prediction speedups while maintaining an adequate classification accuracy compared to training on the original dataset. These results, as well as comparisons to a selection of related state-of-the-art methods from the literature, such as Border Point extraction based on Locality-Sensitive Hashing (BPLSH), Clustering-Based Convex Hull (CBCH), and Shell Extraction (SE), suggest that our proposed methods are effective and potentially useful.
Journal Article
Assessment of the bioactive compounds in gamma irradiated stevia (Stevia rebaudiana Bertoni) leaves
Stevia is a potential alternative sweetener for individuals with diabetes. Gamma radiation is one technique that can alter a plant’s physiological traits or phytochemical makeup without producing any dangerous byproducts or chemical initiators. Therefore, the aim of the current study was to determine the effect of gamma radiation (0, 3, 5, 7, and 10 kGy) on the bioactive compounds of dry stevia leaves. In comparison to non-irradiated samples, it is clear that all gamma radiation doses raised the percentages of carbohydrates, total steviosides, total sugar, reducing sugar, crude protein, and nitrogen, while decreasing the percentages of fat, ash, and fiber. The irradiation of stevia leaves at a dose of 7 kGy resulted in the most significant increase in carbohydrates by 57.7%, total steviosides by 32.8%, total sugars by 38%, reduced sugars by 66.8%, and crude protein by 21.9% when compared to non-irradiated samples. In contrast, the percentages of fat, ash, and fiber decreased by 23.2%, 10.8%, and 11.9%, respectively. According to the HPLC profile chromatogram, stevia leaves exposed to 3, 5, and 7 kGy had higher concentrations of all identified phenolic compounds than non-irradiated leaves; 5 kGy was outperformed by 3 and 7 kGy, while 10 kGy resulted in a decrease in these compounds. While apigenin and ellagic acid only disappeared from leaves exposed to 10 kGy, kaempferol was seen to disappear from all irradiated leaves. Furthermore, cinnamic acid was detected at radiation doses of 5, 7, and 10 kGy (0.50, 0.90, and 0.14 µg.ml
− 1
, respectively), whereas it was absent at the non-irradiated and 3 kGy radiation doses. The Fourier Transform Infrared (FTIR) spectra of the irradiated and non-irradiated stevia samples displayed a comparable band profile. In conclusion, gamma irradiation of dried stevia leaves increased the levels of carbohydrates, steviosides, sugars, crude protein, and phenolic compounds, while reducing the levels of fat, ash, and fiber, with no observable differences in the FTIR spectra between the irradiated and non-irradiated samples. The optimal radiation dose was 7 kGy, which resulted in the most significant enhancement in biologically active compounds, along with the emergence of cinnamic acid.
Journal Article