Desalination is a critical process to address water scarcity in arid regions worldwide, and solar... more Desalination is a critical process to address water scarcity in arid regions worldwide, and solar stills provide an economical solution despite their productivity limitations. This study aimed to enhance the performance and productivity of solar stills by constructing two stills with different natural and artificial absorbing materials such as black luffa, luffa, fine steel wool, and steel wool pads. The solar stills were tested in Egypt under comparable weather conditions, and their productivity, solar intensity, wind velocity, and temperature were measured to determine their thermal efficiency and exergo-economic analysis. Results showed that the choice of absorbing material significantly impacted solar still productivity, with steel wool pads achieving the highest yield of 4.384 l/m2. Moreover, steel wool pads also exhibited the highest thermal efficiency at 32.74%. The cost per liter (CPL) was the lowest with steel wool pads at 0.0034 $/l/m2. Finally, the payback period and exer...
The desalination process is important for converting seawater drinking water in many arid regions... more The desalination process is important for converting seawater drinking water in many arid regions of the world. Solar stills are considered one of the best economical solutions to overcome the shortage of water despite of the limitations in its productivity. In this research two, similar solar stills were designed and fabricated and different absorbing materials were used to increase productivity and enhance the still’s performance. These materials are luffa, black luffa, fine steel wool and, steel wool pads and the performance of the two solar stills were evaluated at the same climate conditions. Different parameters were measured such as the still productivity, solar intensity, temperature, and wind velocity to calculate the still thermal efficiency and the exergoeconomic analysis. The results concluded that the still productivity was about 1.872, 2.923, 3.325, 3.712, and 4.384 l/m2 for conventional solar still (CSS), solar still with luffa (CSS-NLF), with black luffa (CSS-BLF), w...
2020 International Conference on Decision Aid Sciences and Application (DASA)
Accurate and realistic models of forecasting are very relevant as methods for the successful impl... more Accurate and realistic models of forecasting are very relevant as methods for the successful implementation of renewable energy sources into smart grids. This work, present a short-term forecasting of the power output of building photovoltaic system installed in the Heliopolis university, Cairo, Egypt. The proposed method forecast one day using the autoregressive exogenous (NARX) method, based in neural network times series and based in the exogenous input data of the neural networks. The neural network (NN) is trained with Bayesian algorithm to attain the best performance of the forecasted results. However, the NARX neural networks are efficient to overcome a variety of problems and are common for nonlinear control applications as well as for the forecasting. The NARX model opts for accelerated training and level of convergence and good representation and is characterized by attractive dynamics and sensitivity to interference. This model differs in the use of the exogenous neural network input or exogenous variables. The performance of the NARX approach was analyzed as a function of training data sets, error descriptions based on experimental results of the photovoltaic system. The NARX results is compared with experimental data and neural network method. In addition, a statistical criterion is used to evaluate the effectiveness and performance of NARX model. NARX method performed the neural network in term of the statistical criterion which has a low value. Generally, the efficiency and precision of the results depend heavily on the environmental conditions and the data input.
Hybrid photovoltaic thermal solar system becomes one of the potential to play a significant role ... more Hybrid photovoltaic thermal solar system becomes one of the potential to play a significant role in the renewable energy sector. The validation of the photovoltaic/ thermal solar system is not valid in Egypt with proven efficiency of both electrical and thermal system. This paper presents a Comparison between Thermal and PVT performance values for the same area with number of 18 units PVT and 14 units’ thermal units and other parameters to be discussed during the compression in domestic application, see the parameters and boundaries of selected system, and evaluate the performance of each system.
Concentrated PhotoVoltaic Thermal (CPVT ) or as it known in markets as stand-alone unit for the r... more Concentrated PhotoVoltaic Thermal (CPVT ) or as it known in markets as stand-alone unit for the remote areas to supply the area with electricity and thermal hot water which differ for many years with different applications. In Heliopolis University (HU) for Sustainable Development two modules have been tested, thermally and electrically. The module of triple junction photovoltaic is the one which has the ability to work under high temperature. When the concentrated heat was focused on the electric module, the cooling is must to drop the temperature from 120C to 45C. The production of the heat has directed to cool the cell plays important role to use the thermal heat in different applications. The performance of the two modules have been investigated and the whole system has been described in details. At the end the research proposed different types of the thermal modules when it was noted that the useful power produced by the thermal was much power than the electric power produced b...
The effectiveness of SARS-CoV-2 vaccines and therapeutic antibodies has been limited by the conti... more The effectiveness of SARS-CoV-2 vaccines and therapeutic antibodies has been limited by the continuous emergence of viral variants, and by the restricted diffusion of antibodies from circulation into the sites of respiratory virus infection. Here, we report the identification of two highly conserved regions on Omicron variant RBD recognized by broadly neutralizing antibodies. Based on this finding, we generated a bispecific single-domain antibody that was able to simultaneously and synergistically bind these two regions on a single Omicron variant RBD as revealed by Cryo-EM structures. This inhalable antibody exhibited exquisite neutralization breadth and therapeutic efficacy in mouse models of SARS-CoV-2 infections. The structures also deciphered an uncommon cryptic epitope within the spike trimeric interface that may have implications for the design of broadly protective SARS-CoV-2 vaccines and therapeutics.
Numerical modeling and analysis of the baking process are challenging biochemical processes occur... more Numerical modeling and analysis of the baking process are challenging biochemical processes occurring in bread. These changes result from mass engineering tasks, usually characterized by the complex chain of chemical, physical, and heat transfer processes impacting the baking at the same time primarily caused by a variation of two dominating factors: (i) the heat and (ii) the internal moisture content at different temperatures and during the time’s process. This study presents an analysis of the 1-D computational fluid dynamics model for simultaneous heat transfer within a cylindrical bread sample. The numerical simulations were performed using the finite difference model (FDM) and the finite element model (FEM). In the first case, the proposed numerical model considered radiation and convection during sample heating and described the sample’s simultaneous heat, water, and vapor diffusion mechanisms. The calculations indicated that the FDM was susceptible to the time step; consequen...
Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women and a high risk factor f... more Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women and a high risk factor for adverse pregnancy complications. Therefore, we aimed to analyse the relationship between PCOS and pregnancy complications in a large sample from China. Additionally, since obesity and assisted reproductive technology (ART) are common in women with PCOS, we also aimed to determine whether both of these factors increased the complication incidence for women with PCOS. A retrospective cohort study that included 1357 pregnant women with PCOS and 6940 without PCOS was performed. Our results indicated women with PCOS had higher incidence of gestational diabetes mellitus (GDM), hypertension, postpartum haemorrhage, preterm birth, macrosomia and cervical incompetence. Additionally, obesity was associated with an increased incidence of hypertension and GDM in women with PCOS generally. ART did not result in an increase in the obstetric complication rate in women with PCOS. In conclusion, PCOS appeared to result in an increased risk of adverse pregnancy complications. Obesity may further increase the risks of hypertension and GDM among women with PCOS. However, ART did not increase the risk of pregnancy complications, which suggests that ART is a relatively safe and effective method to address infertility problems in women with PCOS.IMPACT STATEMENTWhat is already known on this subject? There are several studies evaluating the associations of PCOS with the risk of pregnancy complications. However, reports about the risk of pregnancy complications between PCOS women with and without obesity or ART are limited.What do the results of this study add? PCOS appeared to increase the risk of adverse pregnancy complications, including GDM, pregnancy-induced hypertension, postpartum haemorrhage, preterm birth, macrosomia and cervical incompetence. Obesity further increased the risks of hypertension and GDM in women with PCOS, but it did not increase the incidence of macrosomia and postpartum haemorrhage. Additionally, ART did not increase the risk of adverse pregnancy complications among women with PCOS, except for postpartum haemorrhage.What are the implications of these findings for clinical practice and/or further research? This study contributes to the literature because it showed that PCOS independently increased the risk of adverse pregnancy complications in a large sample of patients. Second, obesity is a high risk factor for adverse complications in pregnant women with PCOS. Third, ART is a relatively safe and effective method for addressing infertility problems for women with PCOS.
This meta-analysis scrutinized 76 peer-reviewed articles regarding hotel revenue management publi... more This meta-analysis scrutinized 76 peer-reviewed articles regarding hotel revenue management published from 2013 to 2019. The main topics explored were pricing strategy, demand modeling and forecasting, business analysis, performance analysis and evaluation, inventory and price optimization, setting booking controls, and distribution channel management. Furthermore, articles were investigated based on their use of theory, methodology, as well as location. In the end, a comprehensive analysis of gaps in the literature and avenues for future research were provided.
Setting out an international standard schema for the water-energy-food (WEF) nexus and providing ... more Setting out an international standard schema for the water-energy-food (WEF) nexus and providing accurate data with realistic reports for investment through a simple application is essential for our real world. This research presents a tool to help anyone who wants to invest in environmental projects, especially water, energy, or food projects. The user can directly connect to a database of environmental data applying WEF nexus principles. This paper is looking for a mechanism to apply the WEF nexus concept through a web-based platform implementing unified concepts and terminology, setting basic criteria and standards, and making the data available, consistent, and homogeneous. Based on the problem statement, the purpose of this research is to implement a cross-application for sustainable development, including WEF nexus concepts, taking into consideration the interlinkage between the three resources integrated with a business model or financial study for projects. In addition, we h...
Groundwater is considered as one of the main resources especially in remote area. The ground wate... more Groundwater is considered as one of the main resources especially in remote area. The ground water samples are taken from different areas in the study area (Baharia Oasis). Groundwater samples have been analyzed in specialized water quality lab. It was noticed that the iron concentration percentage is higher than the standard limit in most of areas. Using Geographic Information System, the percentage of iron concentration in different unknown areas could be predicted. The results showed that min iron concentration is 0.07 mg/l and the max is 10.5 mg/l. It is recommended to apply an oxidation process in different wells and predict the others using the same process to provide people with safe and sustain drinking water.
Energy produced by photovoltaic panels is affected by orientation and tilting angle. Therefore in... more Energy produced by photovoltaic panels is affected by orientation and tilting angle. Therefore in Building Integration Photovoltaic BIPV systems challenges in maximizing power supply occur in its usage as building envelopes or on greenhouse rooftops. This study has used an actual experiment to compare the effects of orientations south, east or west and tilting angle of 30° or 15° on power generated, and it has tested the effects of different inverter-MPPT set-ups. Experimental data have been compared with a simulation model built in MATLAB. Modelling agreed with the results obtained from the experiments. The results demonstrated the need for dividing the PV panels into two segments groups, each with the same orientation, and each with their own MPPT channel. Combining panel strings with different orientations in a single MPPT leads to significant loss in efficiency. These results demonstrate that for BIPV the planning and design of the photovoltaic power supply must be done in durin...
ABSTRACT The objective of using " reuse" of plants residual in industry... more ABSTRACT The objective of using " reuse" of plants residual in industry: • maximizing the use of those residues on the basis of it is renewable resource full of energy. • accumulation of those residues without use is a significant cause of pollution of the environment everywhere and harmful against humanity.
Desalination is a critical process to address water scarcity in arid regions worldwide, and solar... more Desalination is a critical process to address water scarcity in arid regions worldwide, and solar stills provide an economical solution despite their productivity limitations. This study aimed to enhance the performance and productivity of solar stills by constructing two stills with different natural and artificial absorbing materials such as black luffa, luffa, fine steel wool, and steel wool pads. The solar stills were tested in Egypt under comparable weather conditions, and their productivity, solar intensity, wind velocity, and temperature were measured to determine their thermal efficiency and exergo-economic analysis. Results showed that the choice of absorbing material significantly impacted solar still productivity, with steel wool pads achieving the highest yield of 4.384 l/m2. Moreover, steel wool pads also exhibited the highest thermal efficiency at 32.74%. The cost per liter (CPL) was the lowest with steel wool pads at 0.0034 $/l/m2. Finally, the payback period and exer...
The desalination process is important for converting seawater drinking water in many arid regions... more The desalination process is important for converting seawater drinking water in many arid regions of the world. Solar stills are considered one of the best economical solutions to overcome the shortage of water despite of the limitations in its productivity. In this research two, similar solar stills were designed and fabricated and different absorbing materials were used to increase productivity and enhance the still’s performance. These materials are luffa, black luffa, fine steel wool and, steel wool pads and the performance of the two solar stills were evaluated at the same climate conditions. Different parameters were measured such as the still productivity, solar intensity, temperature, and wind velocity to calculate the still thermal efficiency and the exergoeconomic analysis. The results concluded that the still productivity was about 1.872, 2.923, 3.325, 3.712, and 4.384 l/m2 for conventional solar still (CSS), solar still with luffa (CSS-NLF), with black luffa (CSS-BLF), w...
2020 International Conference on Decision Aid Sciences and Application (DASA)
Accurate and realistic models of forecasting are very relevant as methods for the successful impl... more Accurate and realistic models of forecasting are very relevant as methods for the successful implementation of renewable energy sources into smart grids. This work, present a short-term forecasting of the power output of building photovoltaic system installed in the Heliopolis university, Cairo, Egypt. The proposed method forecast one day using the autoregressive exogenous (NARX) method, based in neural network times series and based in the exogenous input data of the neural networks. The neural network (NN) is trained with Bayesian algorithm to attain the best performance of the forecasted results. However, the NARX neural networks are efficient to overcome a variety of problems and are common for nonlinear control applications as well as for the forecasting. The NARX model opts for accelerated training and level of convergence and good representation and is characterized by attractive dynamics and sensitivity to interference. This model differs in the use of the exogenous neural network input or exogenous variables. The performance of the NARX approach was analyzed as a function of training data sets, error descriptions based on experimental results of the photovoltaic system. The NARX results is compared with experimental data and neural network method. In addition, a statistical criterion is used to evaluate the effectiveness and performance of NARX model. NARX method performed the neural network in term of the statistical criterion which has a low value. Generally, the efficiency and precision of the results depend heavily on the environmental conditions and the data input.
Hybrid photovoltaic thermal solar system becomes one of the potential to play a significant role ... more Hybrid photovoltaic thermal solar system becomes one of the potential to play a significant role in the renewable energy sector. The validation of the photovoltaic/ thermal solar system is not valid in Egypt with proven efficiency of both electrical and thermal system. This paper presents a Comparison between Thermal and PVT performance values for the same area with number of 18 units PVT and 14 units’ thermal units and other parameters to be discussed during the compression in domestic application, see the parameters and boundaries of selected system, and evaluate the performance of each system.
Concentrated PhotoVoltaic Thermal (CPVT ) or as it known in markets as stand-alone unit for the r... more Concentrated PhotoVoltaic Thermal (CPVT ) or as it known in markets as stand-alone unit for the remote areas to supply the area with electricity and thermal hot water which differ for many years with different applications. In Heliopolis University (HU) for Sustainable Development two modules have been tested, thermally and electrically. The module of triple junction photovoltaic is the one which has the ability to work under high temperature. When the concentrated heat was focused on the electric module, the cooling is must to drop the temperature from 120C to 45C. The production of the heat has directed to cool the cell plays important role to use the thermal heat in different applications. The performance of the two modules have been investigated and the whole system has been described in details. At the end the research proposed different types of the thermal modules when it was noted that the useful power produced by the thermal was much power than the electric power produced b...
The effectiveness of SARS-CoV-2 vaccines and therapeutic antibodies has been limited by the conti... more The effectiveness of SARS-CoV-2 vaccines and therapeutic antibodies has been limited by the continuous emergence of viral variants, and by the restricted diffusion of antibodies from circulation into the sites of respiratory virus infection. Here, we report the identification of two highly conserved regions on Omicron variant RBD recognized by broadly neutralizing antibodies. Based on this finding, we generated a bispecific single-domain antibody that was able to simultaneously and synergistically bind these two regions on a single Omicron variant RBD as revealed by Cryo-EM structures. This inhalable antibody exhibited exquisite neutralization breadth and therapeutic efficacy in mouse models of SARS-CoV-2 infections. The structures also deciphered an uncommon cryptic epitope within the spike trimeric interface that may have implications for the design of broadly protective SARS-CoV-2 vaccines and therapeutics.
Numerical modeling and analysis of the baking process are challenging biochemical processes occur... more Numerical modeling and analysis of the baking process are challenging biochemical processes occurring in bread. These changes result from mass engineering tasks, usually characterized by the complex chain of chemical, physical, and heat transfer processes impacting the baking at the same time primarily caused by a variation of two dominating factors: (i) the heat and (ii) the internal moisture content at different temperatures and during the time’s process. This study presents an analysis of the 1-D computational fluid dynamics model for simultaneous heat transfer within a cylindrical bread sample. The numerical simulations were performed using the finite difference model (FDM) and the finite element model (FEM). In the first case, the proposed numerical model considered radiation and convection during sample heating and described the sample’s simultaneous heat, water, and vapor diffusion mechanisms. The calculations indicated that the FDM was susceptible to the time step; consequen...
Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women and a high risk factor f... more Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women and a high risk factor for adverse pregnancy complications. Therefore, we aimed to analyse the relationship between PCOS and pregnancy complications in a large sample from China. Additionally, since obesity and assisted reproductive technology (ART) are common in women with PCOS, we also aimed to determine whether both of these factors increased the complication incidence for women with PCOS. A retrospective cohort study that included 1357 pregnant women with PCOS and 6940 without PCOS was performed. Our results indicated women with PCOS had higher incidence of gestational diabetes mellitus (GDM), hypertension, postpartum haemorrhage, preterm birth, macrosomia and cervical incompetence. Additionally, obesity was associated with an increased incidence of hypertension and GDM in women with PCOS generally. ART did not result in an increase in the obstetric complication rate in women with PCOS. In conclusion, PCOS appeared to result in an increased risk of adverse pregnancy complications. Obesity may further increase the risks of hypertension and GDM among women with PCOS. However, ART did not increase the risk of pregnancy complications, which suggests that ART is a relatively safe and effective method to address infertility problems in women with PCOS.IMPACT STATEMENTWhat is already known on this subject? There are several studies evaluating the associations of PCOS with the risk of pregnancy complications. However, reports about the risk of pregnancy complications between PCOS women with and without obesity or ART are limited.What do the results of this study add? PCOS appeared to increase the risk of adverse pregnancy complications, including GDM, pregnancy-induced hypertension, postpartum haemorrhage, preterm birth, macrosomia and cervical incompetence. Obesity further increased the risks of hypertension and GDM in women with PCOS, but it did not increase the incidence of macrosomia and postpartum haemorrhage. Additionally, ART did not increase the risk of adverse pregnancy complications among women with PCOS, except for postpartum haemorrhage.What are the implications of these findings for clinical practice and/or further research? This study contributes to the literature because it showed that PCOS independently increased the risk of adverse pregnancy complications in a large sample of patients. Second, obesity is a high risk factor for adverse complications in pregnant women with PCOS. Third, ART is a relatively safe and effective method for addressing infertility problems for women with PCOS.
This meta-analysis scrutinized 76 peer-reviewed articles regarding hotel revenue management publi... more This meta-analysis scrutinized 76 peer-reviewed articles regarding hotel revenue management published from 2013 to 2019. The main topics explored were pricing strategy, demand modeling and forecasting, business analysis, performance analysis and evaluation, inventory and price optimization, setting booking controls, and distribution channel management. Furthermore, articles were investigated based on their use of theory, methodology, as well as location. In the end, a comprehensive analysis of gaps in the literature and avenues for future research were provided.
Setting out an international standard schema for the water-energy-food (WEF) nexus and providing ... more Setting out an international standard schema for the water-energy-food (WEF) nexus and providing accurate data with realistic reports for investment through a simple application is essential for our real world. This research presents a tool to help anyone who wants to invest in environmental projects, especially water, energy, or food projects. The user can directly connect to a database of environmental data applying WEF nexus principles. This paper is looking for a mechanism to apply the WEF nexus concept through a web-based platform implementing unified concepts and terminology, setting basic criteria and standards, and making the data available, consistent, and homogeneous. Based on the problem statement, the purpose of this research is to implement a cross-application for sustainable development, including WEF nexus concepts, taking into consideration the interlinkage between the three resources integrated with a business model or financial study for projects. In addition, we h...
Groundwater is considered as one of the main resources especially in remote area. The ground wate... more Groundwater is considered as one of the main resources especially in remote area. The ground water samples are taken from different areas in the study area (Baharia Oasis). Groundwater samples have been analyzed in specialized water quality lab. It was noticed that the iron concentration percentage is higher than the standard limit in most of areas. Using Geographic Information System, the percentage of iron concentration in different unknown areas could be predicted. The results showed that min iron concentration is 0.07 mg/l and the max is 10.5 mg/l. It is recommended to apply an oxidation process in different wells and predict the others using the same process to provide people with safe and sustain drinking water.
Energy produced by photovoltaic panels is affected by orientation and tilting angle. Therefore in... more Energy produced by photovoltaic panels is affected by orientation and tilting angle. Therefore in Building Integration Photovoltaic BIPV systems challenges in maximizing power supply occur in its usage as building envelopes or on greenhouse rooftops. This study has used an actual experiment to compare the effects of orientations south, east or west and tilting angle of 30° or 15° on power generated, and it has tested the effects of different inverter-MPPT set-ups. Experimental data have been compared with a simulation model built in MATLAB. Modelling agreed with the results obtained from the experiments. The results demonstrated the need for dividing the PV panels into two segments groups, each with the same orientation, and each with their own MPPT channel. Combining panel strings with different orientations in a single MPPT leads to significant loss in efficiency. These results demonstrate that for BIPV the planning and design of the photovoltaic power supply must be done in durin...
ABSTRACT The objective of using " reuse" of plants residual in industry... more ABSTRACT The objective of using " reuse" of plants residual in industry: • maximizing the use of those residues on the basis of it is renewable resource full of energy. • accumulation of those residues without use is a significant cause of pollution of the environment everywhere and harmful against humanity.
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