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This study addresses the problem of power outages in distant districts by taking advantage of the available renewable energy resources in the surrounding environment. This was done by proposing connecting the utility to a hybrid system constituting from photovoltaic (PV), wind turbine (WT), and fuel cell (FC) systems where this hybrid system is considered as a backup system that works when the grid is unavailable. This hybrid system proposed is used for feeding the load to a tourist resort in Hurghada, Egypt. The design of the introduced system has taken into consideration the cost of purchasing electric energy and the profit from selling it to the utility network. Component scaling was implemented to improve the net present cost of the proposed system using two grouped meta-heuristic techniques, which are the Hybrid Firefly and Harmony Search optimization technique (HFA/HS) and compared to the particle swarm optimization (PSO) technique. Simulation results have shown that the optimal system for solving the grid unavailability consists of eighty PVs, two WTs, twenty FCs, forty-one electrolyzers, and one hundred eighteen hydrogen tanks. The results also showed that the volume of exchange with the grid has reached 4 GW of purchase and 3 GW of sale. It is manifest from the results that the suggested system is economically viable with an LCOE of 0.0628 $/kWh, which is less than the purchase of electricity from the grid for commercial users in Egypt, which is 0.1 $/kWh.

Developing countries' energy sector faces a multitude of challenges, ranging from inadequate generation to unstable grids. Power outages are among the most common issues, particularly in remote areas. Utilizing grid-tied green energy resources to address this issue and to cover for power outages from local grids. This article presents a cost-effective design of a grid-tied, hybrid green energy system (GES) consisting of wind, PV, and batteries considering the influence of the grid availability. A multi-objective, optimal techno-economic design, optimized by multi-objective particle swarm optimization technique is presented for the grid-tied GES linked to a small hamlet in the north of Egypt. The multi-objective function introduced in this work includes three objective functions which are, the Loss of Power Supply Probability (LPSP), the Cost of Energy (COE), and the System Surplus Energy Rates (SSER) considering the grid availability. The grid availability (GA) of 100% was considered as a base case and it was reduced to 70% with a step of 5%. The simulation consequences had cleared that the lowest and largest percentage values of SSER were obtained at GA of 85 %, and 70 %, respectively. When the value of SSER equal to 0.33%, the system design for solving the grid unavailability consists of 12 PVs, one WT, and 1420 batteries with COE of 0.145$/kWh and TNPC of 3,699,800 ($).

The objective of this treatise is to provide a detailed feasibility analysis of the hybrid renewable energy system (HRES) to supply sufficient energy to an autonomous college’s building et al. Baha University in the Kingdom of Saudi Arabia (KSA). The feasibility analysis presents technical and economic guises for the HRES which includes integrated sources of photovoltaic (PV), wind turbine, fuel cell, and batteries. The utilized real data of the island-building is gathered to support the feasibility analysis of the suggested system which includes monthly load consumption, climate data, and installation available space. The sensitivity analysis and the simulation consequences show that the hydrogen energy system reduces the support of the economic and the ecological factors for the HRES comparing with other resources. PV system also plays a considerable influence on the net present cost and the cost of energy of the system.

A technical-economic investigation based on mathematical modeling, simulation, and optimization approach is employed in this research to assemble an island combined renewable energy systems (CRES) consists of solar PV/Wind/Fuel Cell (FC) of a small-scale countryside area in Egypt. The intent of the proposed island CRES is to boost the share of renewable energy in the energy mix and to study the possibility of using fuel cells as a storage/backup system instead of using battery banks. Three combinations of CRES are presented in this research to select the most optimum one. The combinations of the hybrid systems are PV/FC, PV/WT/FC, and WT/FC. The performance and the total cost of the suggested CRES were optimized using Firefly Algorithm (FA). The results obtained from the FA are compared with those obtained from the Shuffled Frog Leaping Algorithm (SFLA) and the particle swarm optimization (PSO). The selected case study area with latitude and longitude of (29.0214 N, 30.8714 E) is identified for economic viability in this work. The simulation outcomes show that the solar PV/Wind/Fuel Cell combination incorporated with an electrolyzer for hydrogen production grants the excellent performance. The proposed system is economically viable with a levelized cost of energy of 0.47 $/kWh.

This research work crucially deals with a techno-economic feasibility study for off-grid solar photovoltaic fuel cell (PV/FC) hybrid systems. The hybrid renewable energy system is investigated for feeding electric to remote areas and isolated urban regions in Egypt. To achieve this goal, all the system equipment are modeled, simulated and the area under study data is gathered. The objective function is formulated depending on the total annual cost (TAC). The Flower Pollination Algorithm (FPA), as an efficient recent metaheuristic optimization method, proposed to estimate the optimum number of both PV panels and the FC/electrolyzer/H2 storage tanks set mandatory where the least total net present value (TNPV) is reached. The loss of power supply probability (LPSP) is considered to enhance the performance of the proposed design. The effect of the variation of FC, electrolyzer, H2 storage tanks and the PV power system initial cost on the levelized cost of energy (LCOE) is presented through a comprehensive sensitivity analysis. Through Matlab™ program, the numerical simulation results obtained by the FPA algorithm have been compared to the corresponding outcomes while using the artificial bee colony (ABC) and the Particle Swarm Optimization (PSO) techniques. According to the simulation outcomes analysis, the FPA Algorithm has the less fulfillment time and good rendering between the other algorithms. In addition, the optimum system configuration is acquired using FPA with the optimal hybridization of 27 solar PV, 28 FCs, 58 electrolyzers and 37 H2 storage tanks for an LPSP and PEE of 1.52% and 4.68% respectively. The system TNPV is $3,244,897 with the LCOE of 0.334 $/kWh.

Background Cesarean section remains to be one of the most common surgical procedures performed worldwide and available data indicate that surgical interventions constitute approximately 0.4%–40.5% of all deliveries. Surgical site infections (SSIs) are reported to occur in up to 8.4% of women having a caesarean section (CS) with many negative effects, including pain, prolonged hospitalisation or readmission, need for antibiotics, return to theatre and increasing costs. Objective In women undergoing elective caesarian section, subcutaneous tissue irrigation with povidone Iodine may decrease the rate of surgical site infection. Patients and Methods The study included any female from 20 to 35 years old of gestational age 38 week or older with viable fetus, BMI 20-30 Kg/m2. Patient excluded were those with preoperative haemoglobin less than 10, prolonged rupture of membranes, diabetic, hypertensive or with any medical disorder including autoimmune diseases. Results The result of our study demonstrated that the use of povidone iodine 1% solution doesn’t have an added benefit in decreasing the incidence of SSI. Conclusion We conclude that the use of povidone iodine 1% solution in irrigation of subcutaneous tissue prior to skin closure in elective caesarian deliveries does not have an added benefit in decreasing the incidence of SSI and is, thus, not recommended at time being.

Objective To evaluate the effect of pterygium surgery on corneal topography by comparing wave front analysis before and one month after the surgical treatment. Methodology Fifty eyes of forty-one patients were included in this study. Twenty five male and sixteen female patients seeking pterygium surgery were recruited from the Ophthalmology Department Outpatient Clinic in Sohag Teaching Hospital during the period from July 2017 to May 2018. All eyes underwent pterygium excision with conjunctival autograft. Results In this study we found a highly statistically significant improvement in the mean uncorrected visual acuity from 0.44±0.21SD preoperatively to 0.62±0.18SD postoperatively (p Conclusion There was a highly statistically significant difference in the mean logMAR visual acuity and a highly statistically significant improvement in the mean uncorrected visual acuity. A highly statistically significant improvement in both refractive and topographic astigmatism after one month of the surgery was noted also. Here were also a highly statistically significant improvement in ISV and IHD that indicate improvement after pterygium removal. Recommendations Patient with pterygium that inducing astigmatism will benefit from surgical removal of the pterygium.

The cropping pattern considers how to use the available agriculture resources from land, water, farmers ,capital and information technology. Thus the main objective of this study determines the optimum cropping pattern that will maximize net return and maximize net return of irrigation water . To achieve the main objective of this study the method of Goal programming .has used .The results of research shown that: The available area was about 14.63 million Fadden has been fully used , The model maximize the total net return of the current crop in A.R.E.it estimated from 68.51 to 69.17 billion pound annually which increase about 0.66 billion pound which represent 1% from the current crops. While the total quantity of requirement water decrease from 61.19 to 58.95 billion cubic meter ,which decrease about 2.24 billion cubic meter which represent 3.66% of the current quantity of water. While the net return irrigation water for crops increasing from 1.12 to 1.17 pound /cubic meter which increase about 0.054 pound /cubic meter that represent 4.83% of the current net return irrigation water

The main goal of this paper is presenting an optimum and safe design for the proposed high voltage direct current (HVDC) grounding grid for converter station at Badr city in Egypt for uniform and non-uniform soil resistivities. Also, the paper discusses the difference between HVDC grounding grids and high voltage alternating current (HVAC) ones. CYMGRD software was used to estimate the step and touch potentials at the soil surfaces at different conditions. The consequences show that the computed results for step and touch potentials are below the safe limits for human in cases of continuous normal and fault conditions for uniform and non-uniform soil resistivities. From results, touch voltage in a non-uniform layer in continues operation is 17.65 V, and equal to 57. 37V in fault operation.

Background: India’s national tuberculosis (TB) programme recommends that among patients with diabetes mellitus and TB, fasting blood glucose (FBG) be recorded at baseline, the end of intensive phase and the end of continuation phase of TB treatment. We conducted this operational research in select districts of Tamil Nadu, India, in 2016 to determine the availability of blood glucose records and glycemic control status during TB treatment. Methods: This was a descriptive study involving secondary programme data. Glycemic control during TB treatment was ‘optimal’ if both baseline and end of intensive phase FBG (during TB treatment) were Results: Of 438 patients, FBG at baseline, the end of intensive phase and the end of continuation phase were each available in Conclusion: Among patients with diabetes and tuberculosis, recording of FBG during tuberculosis treatment requires urgent attention.

This paper presents a methodology for optimal design of diesel/PV/wind/battery hybrid renewable energy system (HRES) for the electrification of residential buildings in rural areas. Contrary to previous work, in this study, the effects of climate diversity and building energy efficiency on the size optimization of HRES are investigated. First, a multi-criteria spatial analysis trough a common geographical information system tool (ArcGIS 10.2) is undertaken to develop the renewable energy potential map for Algeria. Then, particle swarm optimization algorithm and e-constraint method were used to solve the multi-objective problem, which was formulated to minimize the cost of energy (COE) as the primary objective, while maximizing system reliability and a renewable fraction (RF). According to the resulting renewable potential map, seven zones are identified, and then seven locations have been selected (one from each zone) to execute the optimization of the proposed HRES. By considering low efficient buildings, photovoltaic/wind/diesel/battery is found the best configuration for Adrar and Tindouf, while photovoltaic/diesel/battery is obtained the best for the other locations. However, in the case of high-performance buildings, another optimal HRES configurations are obtained. The better one is acquired in Biskra and Tamenrast, which includes PV-Battery (100% renewable energy) and fulfilling COE of 0.21 $/kWh.

The world's attention is now focused on the growing need to diversify energy sources. Saudi Arabia has the natural stress to take the trait of the huge opportunities in the renewable energy sector. The purpose of this study is to analyze the utilization of the solar, wind and biomass energy in a standalone hybrid power generation system for pastoral electrification in Al-Jouf, Saudi Arabia. To achieve this target, four standalone systems have been introduced which are, PV/Wind, PV/Biomass, Wind/Biomass, and Pt//Wind/Biomass system. Various groups of wind turbines, PV solar systems, and biomass generator are simulated, modeled and optimized to define the ultimate energy dynamic and estimate-effective arrangement for the studied territory. HOMER computer package has been applied to carry out the techno-economic feasibility of the introduced projects, considering the Net Present Cost (NPC), and the Levelized Cost of Energy (LCOE) as frugal points.

The aim of this paper is to compute the electric fields of parallel high and extra high voltage transmission lines in Egyptian power network. Three parallel high and extra high voltage transmission lines are analysed and simulated. The first two lines are the same configurations with voltage of 220 kV, double circuit, two bundles. The third line is a flat configuration, 500 kV, three bundles, and single circuit. The charge simulation technique (CST) is used to calculate the electric field at ground level for these lines. The maximum electric field of the three lines is affected by modifying the phase sequence for each line and the spacings between them. The effect of changing the lines phase sequence on the spatial distribution of the electric field is also studied. The effect of taking one on sub-circuit or line of is out of service is also studied.

The aim of this paper is to calculate the electric fields produced by ultra-high voltage transmission lines. Two transmission lines of different configurations were modeled and simulated. The first line is an 800 kV, flat configuration, six bundles and single circuit in South Africa. The second line is 1100 kV, double circuit, eight bundles, in Japan. The charge simulation technique (CST) is used for calculating the electric field at one meter height underneath these lines. COMSOL computer program is used for electric field calculation at the surface of sub-conductors of for all mentioned configurations. The maximum electric field underneath the lines is 1.9 and 2.1 kVm−1 for the 800, and 1100 kV lines respectively. The effect of the phase sequence on the electric field for the double circuit transmission line is also studied and presented in this work. The average crest values of electric field at the sub-conductors surface for 800 kV line are 20.69, 23.87 and 20.59 kVcm−1 for phase A, B and C respectively against 22.79, 27.19 and 20.51 kVcm−1 for circuit one and 22.68, 27.55 and 20.35 kVcm−1 for circuit two of 1100 kV line.

This paper deals with the mitigation of electric fields under extra high voltage transmission lines using active and passive shield wires. Two extra high voltage alternating current transmission lines are modeled and analyzed. One line is operating at 220 kV and the other is at 500 kV. The electric field is calculated at one meter above the ground level for the two transmission lines with and without active and passive shield wires using the charge simulation method (CSM). The effect of different shielding parameters on the ground level field is studied. These parameters include the spacing between shield wires and their number of these wires, and their height above ground as well as the value of the voltage applied to the shield wires. Also, the effects of passive and active shield wires on the magnetic field underneath the lines and the electric field on the conductor's surface are highlighted.

Motivated by the new feed-in tariffs for electrical power projects generated from renewable energy resources, the present study is investigating the potential of on-grid hybrid solar/wind/Biomass power generation in Egypt. The arrangement is modeled and examined through the environmental and economic prospects. The optimization, sizing and economic assessment of the introduced systems were accomplished using computer package software called HOMER. A case study area, Monshaet Taher village at Beni-Suef Governorate, Egypt with (29° 1′ 17.0718″N, 30° 52′ 17.04″E) is placed for economic feasibility in this study. HOMER optimization model plan was designed with annual average solar radiation scaled of 5.93 (kWh/m2/day), annual average wind velocity for the location is 4.92 m/Sec and average biomass supplying 105 tons per day. The proposed grid connected solar/wind/Biomass hybrid system is an efficient method to cut emissions and the investment of the energy system is not increased.

Little is known about bone mass acquisition among stunted adolescents who did not achieve their growth in height. A national survey was made of bone mineral density among stunted adolescents and adults. A multistage stratified random sample of 2500 families (8476 adolescents and their parents) was selected from 6 governorates in different geographical areas of Egypt. Clinical history, anthropometry and measurement of bone mineral density using dual energy X-ray absorptiometry was done. Mean T-scores were significantly lower among both adults and adolescents with short stature compared with those of normal height. The predictors of bone status among adolescent boys were age, body mass index (BMI), height attained (z-score) and maternal T-score and for girls were BMI, age at menarche, paternal T-score and z-score. Stunted adolescents suffered from low bone mass density and low stature adults suffered a high prevalence of osteoporosis.

Zusammenfassung Durch angiographische Untersuchungen am Praparat und intra vitam sowie durch experimentelle Untersuchungen sollte geklart werden, ob beim Pferd als atiologischer Faktor bei der Osteochondrosis dissecans im Talokruralgelenk an der kranialen Kante der Tibia (Processus coronoideus) umschriebene Durchblutungsstorungen in Frage kommen. In der distalen Halfte der Tibia besteht ein fein verzweigtes System intraossearer Gefase. Insgesamt 4 nutritive Gefase versorgen die distale Tibiaepiphyse. Diese Gefase des epiphysaren Systems anastomosieren untereinander und mit dem distal gerichteten Zweigen der A. nutricia tibiae des medullaren Systems. Nach dem Ergebnis der Untersuchungen werden primare Storungen der arteriellen Gefasversorgung fur die Entstehung der O. d. beim Pferd im Talokruralgelenk nicht angenommen. Summary Arteriographic studies on the distal tibial end in relation to the pathogenesis of Osteochondrosis dissecans in the horse Angiographic studies on prepared tissues and intra vitam, as well as experimental studies, were carried out to determine whether local vascular damage is concerned in the aetiology of Osteochondrosis dissecans in the tibio-tarsal joint on the cranial border of the tibia (Processus coronoideus). In the distal half of the tibia is a finely branched system of intraosseous vessels. A total of 4 nutritive vessels supply the distal tibial epiphysis. These vessels of the epiphyseal system anastomose with one another and with the distally directed branches of the nutrient tibial artery of the medullary system. The results do not support the view that primary damage to the arterial supply is responsible for the development of Osteochondrosis dissecans in the tibio-tarsal joint of the horse. Resume Recherches arteriographiques de la terminaison distale du tibia par rapport a la pathogenese de l'Osteochondrosis dissecans chez le cheval Le but de cette recherche devait expliquer grâce a des examens angiographiques sur preparation, intra vitam et par des investigations experimentales si des troubles circulatoires circonscrits entraient en ligne de compte comme facteur etiologique lors d'Osteochondrosis dissecans dans l'articulation talo-cruriale au bord cranial du tibia (Processus coronoideus). Il existe un systeme de reseaux fins de vaisseaux intraosseux dans la moitie distale du tibia. 4 vaisseaux nourriciers alimentent l'epiphyse distale du tibia. Ces vaisseaux du systeme epiphysaire s'anastomosent entre eux et avec les branches distales d'A. nutricia tibiae du systeme medullaire. Les resultats n'ont pas permis d'attribuer l'apparition d'une Osteochondrosis dissecans dans l'articulation talo-cruriale du cheval a des troubles primaires de l'approvisionnement des vaisseaux arteriels. Resumen Estudios arteriograficos del extremo distal de la tibia con respecto a la patogenia de la osteocondrosis disecante en el caballo Mediante estudios angiograficos en la preparacion e intra vitam asi como por medio de pesquisas experimentales queriamos esclarecer si intervienen en el caballo defectos circunscritos en la irrigacion sanguinea como factor etiologico en la osteocondrosis disecante en la articulacion talocrural en la arista craneal de la tibia (proceso coronoides). Existe en la mitad distal de la tibia un sistema finamente ramificado de vasos intraoseos. Estos vasos del sistema epifisario se anastomosan entre si y con las ramas de direccion distal de la a. nutricia de la tibia del sistema medular. Con arreglo al resultado de las investigaciones realizadas, no admitimos el que las lesiones primarias en el abastecimiento vascular arterial sean decisivas en la patogenia de la o. d. en el caballo en la articulacion talocrural.

This paper is aimed at reducing the electric fields underneath extra high voltage directcurrent transmission lines using grounded shield wires. Two extra high voltage directcurrent transmission lines are modeled and analyzed. One line is homopolar and theother is bipolar, both are operating at 400 kV. The electric field calculated at the groundlevel for the two transmission lines with and without grounded shield wires. In addition,the right-of-way limits for those transmission lines according to the maximum allowableelectric field strength are calculated. The charge simulation method is used forcalculating electric fields underneath the lines with and without grounded shield wires.

Purpose: To study bone mineral density and bone markers in stunted adolescents. Design: Case-control study. Subjects and Methods: The subjects were 159 stunted boys and girls, mean age (13.26±2.00 years) from the stunting out-patient clinic of the National Nutrition Institute, Cairo, Egypt. The control group was 159 age-, sex- and socio-economically matched adolescents with normal height for age. Clinical history, anthropometry, bone mineral density and various laboratory parameters [haemoglobin concentration, serum calcium, phosphorus, magnesium, copper, alkaline phosphatase, serum osteocalcin (as a marker of bone formation), urinary calcium/creatinine ratio] were estimated. Results: The mean bone mineral density was significantly lower among the stunted group compared with the control group. Serum levels of calcium and magnesium were significantly lower among the stunted group. Serum alkaline phosphatase activity was significantly higher among the stunted group; no significant difference was found in th...

The extensive availability of electromagnetic technology has led to increasing concerns on the possible health hazards. Meanwhile the EM interactions with biological materials have generated considerable interest in a variety of biological and medical applications. The main application of this work is to treat skin cancer using Impulse Radiating antenna because of its effective focus on the affected area only. Impulse Radiating Antenna can radiate very fast electromagnetic pulse with high field amplitude. Recent research shows that such pulse can be used to kill melanoma cells. This antenna uses Intense sub Nano second electric pulse for radiating on the skin. This way of treating cancerous cells ensure very less radiation on the normal part of our body. The design provides a new way of treating skin cancer, which assures better treatment than the rest one due to its effective focus, high gain and effectively treats deep-seated tumors. This paper shows that the enhanced gain of dual tapered arm compared to tradition arm feed arm. Simulation of designed antenna using CST Studio Suite and its observed parameters are open in this paper.

A growing attention is paid to wind energy as clean with potential of economically feasible resource. Earlier works support onshore wind farms for its lower construction and electricity generation costs. The Gulf of Suez region in Egypt, though rich in wind, is a pathway for the birds' migration from east and west Europe to east and middle Africa during autumn seasons and back to Europe during spring seasons. The heights of birds' pathways are less than 100m onshore with population rate reaches around 500 birds/hour. This poses as a real problem to wind turbines with typical elevations which is near to the pathway elevation. To overcome this problem, it is suggested either to use turbines having elevations higher than 100 m height, using turbines with elevations between 40-70m or relocating the wind farm offshore at least 10 km away from the Sea shore. This paper provides technical analysis for the onshore wind turbines with appropriate elevations to avoid bird migration pathways. The production cost is evaluated and found less expensive than the international cost figures.