Ahmed Ibrahim – författare

This book focuses on the issue of optimizing radio resource allocation (RRA) and user admission control (AC) for multiple multicasting sessions on a single high altitude platform (HAP) with multiple antennas on-board. HAPs are quasi-stationary aerial platforms that carry a wireless communications payload to provide wireless communications and broadband services. They are meant to be located in the stratosphere layer of the atmosphere at altitudes in the range 17-22 km and have the ability to fly on demand to temporarily or permanently serve regions with unavailable telecommunications infrastructure. An important requirement that the book focusses on is the development of an efficient and effective method for resource allocation and user admissions for HAPs, especially when it comes to multicasting. Power, frequency, space (antennas selection) and time (scheduling) are the resources considered in the problem over an orthogonal frequency division multiple access (OFDMA) HAP system.Due to the strong dependence of the total number of users that could join different multicast groups, on the possible ways we may allocate resources to these groups, it is of significant importance to consider a joint user to session assignments and RRA across the groups. From the service provider''s point of view, it would be in its best interest to be able to admit as many higher priority users as possible, while satisfying their quality of service requirements. High priority users could be users subscribed in and paying higher for a service plan that gives them preference of admittance to receive more multicast transmissions, compared to those paying for a lower service plan. Also, the user who tries to join multiple multicast groups (i.e. receive more than one multicast transmission), would have preferences for which one he would favor to receive if resources are not enough to satisfy the QoS requirements.Technical topics discussed in the book include: • Overview on High Altitude Platforms, their different types and the recent works in this area Radio Resource Allocation and User Admission Control in HAPs Multicasting in a Single HAP System: System Model and Mathematical Formulation Optimization schemes that are designed to enhance the performance of a branch and bound technique by taking into account special mathematical structure in the problem formulation

This book focuses on the issue of optimizing radio resource allocation (RRA) and user admission control (AC) for multiple multicasting sessions on a single high altitude platform (HAP) with multiple antennas on-board. HAPs are quasi-stationary aerial platforms that carry a wireless communications payload to provide wireless communications and broadband services. They are meant to be located in the stratosphere layer of the atmosphere at altitudes in the range 17-22 km and have the ability to fly on demand to temporarily or permanently serve regions with unavailable telecommunications infrastructure. An important requirement that the book focusses on is the development of an efficient and effective method for resource allocation and user admissions for HAPs, especially when it comes to multicasting. Power, frequency, space (antennas selection) and time (scheduling) are the resources considered in the problem over an orthogonal frequency division multiple access (OFDMA) HAP system.Due to the strong dependence of the total number of users that could join different multicast groups, on the possible ways we may allocate resources to these groups, it is of significant importance to consider a joint user to session assignments and RRA across the groups. From the service provider''s point of view, it would be in its best interest to be able to admit as many higher priority users as possible, while satisfying their quality of service requirements. High priority users could be users subscribed in and paying higher for a service plan that gives them preference of admittance to receive more multicast transmissions, compared to those paying for a lower service plan. Also, the user who tries to join multiple multicast groups (i.e. receive more than one multicast transmission), would have preferences for which one he would favor to receive if resources are not enough to satisfy the QoS requirements.Technical topics discussed in the book include: • Overview on High Altitude Platforms, their different types and the recent works in this area Radio Resource Allocation and User Admission Control in HAPs Multicasting in a Single HAP System: System Model and Mathematical Formulation Optimization schemes that are designed to enhance the performance of a branch and bound technique by taking into account special mathematical structure in the problem formulation

Bachelor Thesis from the year 2014 in the subject Engineering - Aerospace Technology, grade: 4.0, Cairo University, language: English, abstract: This document describes a B.Sc. graduation project (2014). The main objective of this third iteration of the Cairo University Cube Satellite is the design, manufacturing, building and testing selected subsystems of Cube Satellite. The mission of the Cube satellite is Earth imaging and the whole process uses COTS. This document is organized the introduction and six chapters each describes one of the selected subsystems. The mission analysis and orbital determination chapter selects the best orbit matched to the mission requirements. The electrical power subsystem generates energy via the sun, distributes and manages the power among the other subsystems. The attitude determination and control is responsible for the orientation of the Cube Satellite in orbit, and controls the orientation of the Cube Satellite. The communications subsystem is responsible for the data transmission from/to the Cube satellite and the ground station. The command and data-handling center (On Board Computer) handles all the data and commands on the Cube satellite and controls the Cube satellite modes and states. Finally, the structure subsystem chapter includes design the cube satellite structure, stress and weight analysis, inertia and natural frequencies determination. All collected and auxiliary data, code snippets, specification sheets etc. are presented in eight appendices at the end of the document. A secondary objective is enrich the documentation of the current level of the knowhow achieved by the participants of the project.

Research Paper (postgraduate) from the year 2015 in the subject Economy - Environment economics, grade: 4.0, The American University in Cairo, language: English, abstract: Most of the countries aim to reach the state of social well-being, environmental well-being, and economic well-being to preserve the environmental resources, make profits and make the society safe and prosper. This target is defined as the green economy concept which need the innovation to create new technologies and strategies. Therefore, this type of economy is related to a great extent to entrepreneurship. This report discuss the relation between the green economy and the entrepreneurship. Moreover, it gives many case studies in different fields to clarify this relationship needs and results on the society, environment and the economic.

Research Paper (postgraduate) from the year 2015 in the subject Economy - Environment economics, grade: 4.0, The American University in Cairo, language: English, abstract: Sustainable development is considered to be the main solution for various environmental problems facing the world nowadays. In this project, we are going to discuss the definition and importance of sustainability. Moreover, this Project States the condition of C&D (construction and demolition) wastes in Egypt, and their handling. It also explains the concepts of zero waste and green entrepreneurship, and connects these concepts through a variety of integrated case studies. Therefore, we can define a solution to the C&D waste problem in Egypt. The vision of the report that C&D wastes is one from the largest and most hazard wastes in Egypt and up to now Egypt does not appreciate the economic value in these wastes and does not realize their environmental impacts on the people health nor their social impacts on the free lands which are used to be dump sites for these wastes. The report show five case studies aim to reach 100% recycling or zero waste and build green entrepreneurship for C&D waste. This connection between zero waste and build green entrepreneurship will produce comprehensive solution for C&D waste in Egypt to solve the different aspects of this problem and get great economic benefit through this solution.

Project Report from the year 2016 in the subject Environmental Sciences, grade: 4.0, The American University in Cairo, language: English, abstract: Tires are critical components of the vehicles on which they are used. They are used on automobiles, trucks, buses, farm tractors, earth-moving equipment, military vehicles, bicycles, motorcycles, and aircraft. Tires support the weight of the vehicle and the passengers and cargo on board; they transmit the motor torque to propel the vehicle (except on aircraft); and they absorb vibrations and shock to provide a comfortable ride. A tire is a textile/rubber composite. The tire composite is in the form of a network of textile cord structures arranged in a parallel configuration and imbedded in a rubber matrix. Rubber defined as an elastomer compounded with various fillers and chemical ingredients . Most rubber compounds are thermosets, and they are turned into finished molded parts by compression, transfer or injection molding. The tire is made up of numerous different rubber compounds, many different types of carbon black, fillers like clay and silica, and chemicals & minerals added to allow or accelerate vulcanization. The tires also have several types of fabric for reinforcement and several kinds and sizes of steel. Some of the steel is twisted or braided into strong cables.

This book focuses on the issue of optimizing radio resource allocation (RRA) and user admission control (AC) for multiple multicasting sessions on a single high altitude platform (HAP) with multiple antennas on-board. HAPs are quasi-stationary aerial platforms that carry a wireless communications payload to provide wireless communications and broadband services. They are meant to be located in the stratosphere layer of the atmosphere at altitudes in the range 17-22 km and have the ability to fly on demand to temporarily or permanently serve regions with unavailable telecommunications infrastructure. An important requirement that the book focusses on is the development of an efficient and effective method for resource allocation and user admissions for HAPs, especially when it comes to multicasting. Power, frequency, space (antennas selection) and time (scheduling) are the resources considered in the problem over an orthogonal frequency division multiple access (OFDMA) HAP system.Due to the strong dependence of the total number of users that could join different multicast groups, on the possible ways we may allocate resources to these groups, it is of significant importance to consider a joint user to session assignments and RRA across the groups. From the service provider's point of view, it would be in its best interest to be able to admit as many higher priority users as possible, while satisfying their quality of service requirements. High priority users could be users subscribed in and paying higher for a service plan that gives them preference of admittance to receive more multicast transmissions, compared to those paying for a lower service plan. Also, the user who tries to join multiple multicast groups (i.e. receive more than one multicast transmission), would have preferences for which one he would favor to receive if resources are not enough to satisfy the QoS requirements.Technical topics discussed in the book include: • Overview on High Altitude Platforms, their different types and the recent works in this area¿ Radio Resource Allocation and User Admission Control in HAPs ¿ Multicasting in a Single HAP System: System Model and Mathematical Formulation ¿ Optimization schemes that are designed to enhance the performance of a branch and bound technique by taking into account special mathematical structure in the problem formulation

This book focuses on the issue of optimizing radio resource allocation (RRA) and user admission control (AC) for multiple multicasting sessions on a single high altitude platform (HAP) with multiple antennas on-board. HAPs are quasi-stationary aerial platforms that carry a wireless communications payload to provide wireless communications and broadband services. They are meant to be located in the stratosphere layer of the atmosphere at altitudes in the range 17-22 km and have the ability to fly on demand to temporarily or permanently serve regions with unavailable telecommunications infrastructure. An important requirement that the book focusses on is the development of an efficient and effective method for resource allocation and user admissions for HAPs, especially when it comes to multicasting. Power, frequency, space (antennas selection) and time (scheduling) are the resources considered in the problem over an orthogonal frequency division multiple access (OFDMA) HAP system.Due to the strong dependence of the total number of users that could join different multicast groups, on the possible ways we may allocate resources to these groups, it is of significant importance to consider a joint user to session assignments and RRA across the groups. From the service provider's point of view, it would be in its best interest to be able to admit as many higher priority users as possible, while satisfying their quality of service requirements. High priority users could be users subscribed in and paying higher for a service plan that gives them preference of admittance to receive more multicast transmissions, compared to those paying for a lower service plan. Also, the user who tries to join multiple multicast groups (i.e. receive more than one multicast transmission), would have preferences for which one he would favor to receive if resources are not enough to satisfy the QoS requirements.Technical topics discussed in the book include: • Overview on High Altitude Platforms, their different types and the recent works in this area Radio Resource Allocation and User Admission Control in HAPs Multicasting in a Single HAP System: System Model and Mathematical Formulation Optimization schemes that are designed to enhance the performance of a branch and bound technique by taking into account special mathematical structure in the problem formulation

Many steps in your life''s journey, each step is different from the others, whether before or after, more details in your steps, a clear secret but inside you, darkness and destruction, a parallel world, a high light, lines, years, days, months, a mysterious story, no one knows. He explains it, you are the only one who can, no matter how much you say you won''t; You were able to break the barriers between you and yourself. You achieved your dream, but it was late. It is true that you arrived, but it was broken. But you arrived at the end.

A girl''s hormones are among the most difficult hormones you will encounter in your life. If you focus on her, she will get tired. If you talk to more than one girl, she will get tired. Do you want to cheat on her? Betray her, no one knows anything, but if you want my advice, I will tell you no, do you know why? I won''t tell you it''s forbidden; Because it is generally forbidden, but I will tell you that if you want to cheat on her, then cheat on her with her; Because every moment has a different mood, especially before and after 12 o''clock.