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Recycling of concrete waste to produce ready-mix alkali activated cement
No full textCeramics International
Volume 44, Issue 6, 15 April 2018, Pages 7300-7304The goal of this study is to produce an environmentally, and user friendly ready-mix alkali activated cement (RM-AAC) by thermal activation of concrete waste (CW) in the presence of sodium hydroxide (NaOH). Two major compositional factors, which play an important role in the performance of RM-AAC, i.e. temperature and NaOH percentage, were investigated. The CW showed high stability under thermal treatment up to 1200 °C; meanwhile it can be converted to distorted structure with high amorphicity in the presence of appropriate NaOH content. RM-AAC powder can react with water, forming hardened material with an acceptable compressive strength. Due to the white color of RM-AAC powder, it can be beneficially used in prestige construction projects and decorative works
The impact of the Red Dead project on the tourism in Egypt
No full textThe dead sea is located along the borders between Palestine and Jordan, this sea is very salty where it’s salinity about 34% and this percentage is nine times the salinity in the red sea also the dead sea is located at a depth of 400 meters below the surface of the water. But recently the water of the Dead Sea has been shrinking where it decreases about 30% in the last 20 years, so the problem is when the sea surface decreases that leads to raise the water density and salinity where that leads to shrinking the sea water. The main causes of the dead sea shrinks first, Israel and Jordan are exploiting the dead sea water in industry where there are a lot of factories that work in extraction of salts and this requires a huge amount of water, also they exploiting the water of Jordan river in crop cultivation and using it’s fresh water in drinking so as the result the supporting source of the dead sea became not enough to compensate the shortage that happened in the dead sea, in addition to the surrounded environment of the dead sea which is “ desert” where the rainfall in this area is very rare, and there is a Large amount of water have been transferred to Al- Nakeb Deseret. Shrinking the dead sea water will have led to harmful problems such as the inability to dive in the dead sea, where the dead sea water known that it consists of many minerals and salts also its mud one of the most important reasons for health tourism in Jordan also its water treats many diseases like asthma and psoriasis where the ultraviolet rays in this area are very low which allows the psoriasis patients to sit long time under sun. Thus the project of the red sea- dead sea pipelines was suggested to solve the problem of shrinking the dead sea water where amount of the red sea water will be transferred from “gulf Aqaba” area through an open or closed pipeline it’s length about 180 Km to “Lisan” area in the dead sea to compensate the shortage that happened in the dead sea water. Also the water treatment satiation will be established and half of pure water will be transferred to Jordan and Israel and half of the red sea water will be transferred to the Dead Sea. In order to establish this project Israel, Palestine and Jordan signed an agreement between the world bank in march 2013 where the world bank will support this project because its cost is very high that can reach 11 billion dollars also there are some donors who will support this project and in November, 27, 2016 the Jordanian government announced that the first phase of the project will begin in the first of 2018 and it will end in 2021 and this phase will cost about 2.5 million dollars. The positive impacts of this project are, first to fill the need for fresh water in Jordan, Israel and Palestine and thus the stability of the support sources of water of the dead sea like Jordan river, second to improve the improve the economic and tourism sectors, third establishing fish farms for fish production, and finally a huge land reclamation in the area of “Araba valley”. The advantages of this project that serve the interest of Jordan, Israel and Palestine are less than the disadvantages and damages that that will happened to the red sea and dead sea such as: Mixing of dead sea- red sea water, where transferring the red sea water to the dead sea water will lead to (gypsum deposition, changing in the dead sea biogeochemistry). As well as the red sea water have less salt concentration than the dead sea so, the difference in salinity in both seas will damage the chemical composition of the dead sea and that will lead to decrease the health benefits of the dead sea water and its mud also the health and spa tourism will be affected negatively. Damage to the red sea coral reefs, where the red sea consists of more than 200 different types of coral reefs, so the construction activities and the huge amount of water that will be taken from the red sea will definitely affect negatively in the marine eco-system where, the coral reefs in gulf Aqaba are surfers from stress and dying gradually so, as the result this process will scanning them out easily. The impact of excavation: where the pipeline of the project will cross some archeological areas in Wadi Araba such as Wadi Finan. So at the end and according to my point of view this project has a negative impact on red sea and Dead Sea where in the red sea the coral reefs will be damaged as well as the archeological areas which mean the tourism in the red sea will disappear also
Effect of Extinguishing Method on the Behavior of RC Columns Subjected to Fire
No full textConcrete is more durable against fire than other structural materials. However, high temperature has deteriorating effects on mechanical properties of concrete. Decreases of strength at higher temperatures can be associated with various reasons, such as micro-and macro-cracks on the concrete, the volume expansion in the aggregate, and the deterioration of the calcium silicate hydrate (C-S-H) gels in the cement paste.
The main objective of this research work is to study the effect of four different cooling schemes on the ultimate strength of 54 reinforced concrete columns subjected to fire. The tested columns are of different surface area to volume ratios (with three different cross sections; circular, square and rectangular). Four cooling schemes were used; three of them are uniform cooling schemes with different rates (rapid, slow and intermediate) while the fourth cooling scheme was non-uniform. Two different fire temperatures and durations were considered (300oC for 3 Hours & 600oC for 6 Hours). Non Destructive tests (Core & Ultrasonic Pulse Velocity tests) were used to estimate the deterioration extent of fire on concrete properties.
A mathematical model was developed to estimate the ultimate strength of RC columns subjected to fire in order to decide if the R.C. columns need repair and strengthening after fire or not. Results of the model and the obtained experimental results were compared together to evaluate the accuracy of the proposed model.Supervised By Dr. Yehia Abdel Zaher Ali ; Dr. Mohamed Abdel Moaty Khalaf ; Dr. Mohamed Kohail Faye
Interfacing of PV System Based on Dual Cascaded Inverter
No full textSubmitted in partial fulfillment of the requirements for the M.Sc. degree in electrical engineeringThe power electronics converters are coming into wide scale in different fields due to their ability of producing high quality current with low harmonic content, speed and dynamic response for variable change of the load. Power electronics converters provide precise control over wide range of application for electric drive systems, electric traction, ship propulsion and automotive application. In additions, converters are used widely for energy conversion, grid connection, manufacturing, mining and petrochemical. All of these applications require cost reduction, high production rate, high performance and efficiency, which could be served by power electronics systems. This thesis presents an interfacing system of a photovoltaic (PV) array with an electrical grid based on a dual cascaded inverter which consists of main and auxiliary inverters. The PV array is connected to the main inverter through a boost converter for maximum power extraction, while the dc-side of the auxiliary inverter is connected to a capacitor bank. The main and auxiliary inverters are controlled to deliver the harvested maximum power from the PV array to the grid and simultaneously regulating the dc-side voltage of the auxiliary inverter at a constant ratio from the dc-link voltage of the main inverter. Four Hysteresis controllers are proposed for the three-phase currents fed to the grid and the dc-side capacitor voltage of the auxiliary inverter. Two switching control methods are adopted for the dual cascaded inverter: the conventional Hysteresis Current Control (HCC) and the Space Vector Modulation (SVM) based HCC. The later technique offers reduced switching numbers for both inverters compared with the conventional HCC. The system has been also studied during fault / voltage sag condition. A low voltage ride through (LVRT) controller is adopted to fulfill the E.ON grid code requirements. The E.ON grid code ensures that the proposed PV interface system supplies reactive power to the grid according to the value of voltage at the point of common coupling. The proposed dual cascaded inverter for the PV interface system is studied using EMTDC/PSCAD software package. Different test scenarios are conducted under different conditions to evaluate the dynamic behavior of the proposed system. Simulation results show fast dynamic response and accurate performance of the proposed control systems.Supervised by: Dr. Mohamed Abd Al-Raheem Badr ; Dr. Mostafa Ibrahim Mohamed Mare
How does the Grand Ethiopian Renaissance dam affect the agriculture economy in Egypt from 2000 to 2017?
No full textIn the research proposal that analyze the effect of the Ethiopian dam in the agriculture economy that consider a matter of life or death , the Ethiopian dam has been identified by the united states bureau of reclamation during blue Nile survey in 1964, the dam called the Millennium dam, the Ethiopian dam has a potential around 45,000 MW of hydropower and it is funded by the government bonds and private donations. the first of the establishment of this dam at first Egypt had refused the completion this project and asked for regional support for it is position because Egypt was fear that a temporary reduction of water availability due to filling the dam and permanent reduction due to the evaporation from the reservoir ,while other countries have supported that dam as Sudan .But Ethiopia replied to Egypt rejection for constructing the dam by determine that the Ethiopian dam will not have any negative effect on downstream water flow to and determined that the dam in fact will increase water flow to Egypt by reducing evaporation in lake Nasser.
According to the Ethiopian determination about That the dam construction will have no negative effect on the Egypt water flow , This paper will analyze and determine the opposite direction ,As this Dam will affect Egypt water supply and agriculture negatively not positively and the contribution that will be added in this paper that is How to minimize those negative impacts that will face Egypt toward dam construction with using new scenarios and methods that will reducing it is loss in water supply that will directly affect negatively our agriculture economy . this paper includes 3 chapters that explain and shows the potential effects of the construction of the Grand Ethiopian dam on affecting the agriculture sector through different variables included in the Agriculture economy at which each of them includes in the Agriculture process and without their existing in the economy the agriculture process will not be sufficient and this will negatively affect the agriculture sector through many indicator and from different perspective
The Effect of Human Capital Investment on Economic Development: The Case of the Middle East and North Africa Region
No full textIt is without a doubt that achieving sustainable development has become the primary goal for any country, from the most developed to the least developed. However, the reason as to why some countries have failed to achieve this goal remains unidentified. It is claimed that the lack of the capacities necessary to achieve sustainable development has obstructed these countries from achieving said goal. Accordingly, economists have tried for long to identify the determinants of economic development as well as explain the development process. Traditional growth theories attributed economic advancement to investment in both physical capital and technology; which is triggered by savings. However, these theories do not pay much attention to human capital, although there is strong evidence of a close link between human capital investment and economic advancement.
It is widely accepted that human capital is among the main driving forces of economic development. However, the means by which human capital interferes with the development process is what we endeavour to discover. Different growth theories, namely neo-classical and exogenous growth theories, attribute human capital to economic development in different ways. In addition, many published studies draw on the positive relationship between individual and social welfare and human capital investment (Mariana, 2015). However, none of these studies considered the challenges encountered by different regions which undermine the impact of increased human capital investment on economic development. One of these regions is the Middle East and North Africa (MENA) region; which displays a rather peculiar case. Despite several decades of revenues from oil generation, this region remains to be categorized as underdeveloped. While some authors propose being a single-sectored economy, political reasons, or even the lack of efficient institutions as reasons, we propose that the reason is the lacking of sufficient, quality-oriented human capital investment
The impact of the Electronic communications technology and development of internet in Africa
No full textAdvance can be regarded as a principal resource in budgetary alter and changing mechanical changes that contribute completely to the advance of energetic nations. Inventive progress and cash related progress are truly related to each other. In advance, the level of advance may be a noteworthy marker of budgetary modify. A quick rate of progress can be wrapped up through a long level of progress. Schumpeter saw advance or mechanical advance as a sign of budgetary advance. But in case the level of progress is persevering, the way of movement depends. In this way, mechanical advance is what keeps the economy moving. Advancements and advance were by and huge subordinate on speedy cash related alter internal parts the nations that were made. The African area is greatly behind the other locale in utilizing data and communication impels. The Complex socio‐economic issues are major deterrents to the dispersal of organizing headway interior the locale. Small mindfulness on the respect of organizing for doing combating underdevelopment is the major bottleneck for execution of data and communication advancement wanders. Africa, is well known for its down and out broadcast communications foundation. As all known, Organizing and broadcast communications offer different unused openings and conceivable comes about for upgrade. This can’t be wrapped up without bolster among governments.
As, governments got to make an engaging environment for organize in show disdain toward of the truth that suppliers have to be recognize the contrasts of the mechanical levels, approaches, national settings, etc. To come up with changing courses of movement and back procedures
KNOCKS Application
No full textImagine a world without a social media application, well, the universe will not collapse without the social media and people will not die if it has vanished, But the advantage of the social media that would really destroy huge businesses and disassemble the enormous networking connections among people. However,“social media” are defined as any Web sites, portals or applications that allow individuals to post and share content publicly, which allow other individuals to view, respond and share this content further. These media include digital-based applications such as public blogging and micro-blogging; music, image, audio and video sharing; review and opinion sharing; gaming and entertainment; location-based, event-based and occupation-based networks; information and news aggregation; presentation sharing; advocacy and fundraising; creation of virtual worlds; and all-purpose wide-appeal networks geared toward general audiences.[1] Moreover, before 1999 when the social media applications were not well recognized by the majority of people it would not really matter the idea of having a real connection via the internet even theoretical because of the social media complexity which people cannot absorb, and also because of the explosion of mobile phone then that made people think that they are in fantasy world for the reason that they can talk to the someone with a wireless mobile device, But now after the penetration of the social media applications in our lives, we actually cannot give it away under any circumstances; thats why it is a must to develop social media applications that supply their demands and strengthen their networking bonds by allowing them to do mostly everything they want with a single click. For context, as of October 2017, total worldwide population is 7.6 billion and The internet has 3.5 billion users[2], and that emphasizes the importance of the social media applications in our live, as a matter of fact not all of them or even the half of them are individual end users accounts, they can be brands retails and small businesses marketing accounts, There are 3.03 billion active social media users 91% of retail brands use 2 or more social media channels, and 81% of all small and medium businesses use some kind of social platform [2]. Internet users have an average of 7.6 social media accounts Social media users grew by 121 million between Q2 2017 and Q3 2017.Othman , Mahmoud Sami
Radwan , TA. Salm
Photovoltaic Solar Tracking System with Dual Axis
No full textSupervisors
Prof. Dr. Eng. Mahmoud Abd El-Rasheed Noiser
Dr. Eng. Mohamed A. KaraliSolar energy is a safe alternative to replace current fossil fuels like coal and natural
gas for the generation of electricity. Without any pollution for air, water and land. As
traditional power plants produce a lot of harmful gases for the environment causes the
greenhouse phenomena, more over it helps for the depletion of ozone layer.
Sunlight received by the earth in one hour is enough to meet the annual energy
consumption of the world.
Solar photovoltaic are devices that converts sunlight directly into electrical energy, the
electricity produced by the solar cells is clean and silent. Solar tracking system will
allow the tracking of the sun’s movement and the orienting of the PV modules to be
perpendicular to the sunrays, obtaining the maximum solar energy generation.
The current project is studying the importance of photovoltaic system equipped with
dual axis tracking system in order to gain maximum power from the solar irradiance,
while comparing the output of this tracking system to a non-tracking one
The fees and taxes in gulf countries on foreign labor from 1989 till 2018 (Honor thesis)
No full textthis paper is talking about the impact and the rises of taxes nowadays in gulf countries specially on expatriates, how it can impact on their life style and on their standard of living also will be talking on about the (VAT value added tax) Why do the gulf need to impose these taxes and how they will impose it How it can be a useful for gulf countries but not the foreign labor in GCC and how it will make the local people treat the foreigners because the foreigners are broken winged and they will be more low from the foreigners because all their money will be consumed on the taxes that are composed from the government and will not be composed on local people or not at the same level it will be more lower than they pay so foreigners will have grudge through local people and in a big level they may leave the country and leave the gulf countries because it will be the same as their countries they may also make revolutions that may go in the wrong way with them My contribution will be how the taxes impact on expatriate