D2D communications in 5G mobile cellular networks : we propose and validate a novel approach to mobility management

University of Technology Sydney. Faculty of Engineering and Information Technology.Fifth Generation (5G) stands for future fitness combined with flexible technical solutions that combine with the latest wireless technology. 5G is expected to multiply a thousand times (1000x) in data speed with 20.4 billion devices (IoT) connected to the network by 2020. This literally means everything connecting to everything. From the network point of view, lower latency along with high flexibility is not limited just to 5G. It is already being implemented in real networks. The number of wireless devices connected to networks has increased remarkably over the last couple of decades. Ubiquitous voice and data connections are the fundamental requirements for the next generation of wireless technology. Device-to-Device communication is widely known as D2D. It is a new paradigm for cellular communication. It was initially proposed to boost network performance. It is considered to be an integral part of the next generation (5G) of telecommunications networks. It takes place when two devices communicate directly without significant help from the base station. In a cellular network, Device-to-Device communication has been viewed as a promising technology overcoming many existing problems. These include capacity, quality and scarce spectrum resources. However, this comes at the price of increased interference and complex mobility issues, even though it was proposed as a new paradigm to enhance network performance. Nevertheless, it is still a challenge to manage devices that are moving. Cellular devices without well-managed mobility are hardly acceptable. Considering in-band underlay D2D communication, a well-managed mobility system in cellular communication should have lower latency, lower power consumption and higher data rates. In this dissertation, we review existing mobility management systems for LTE-Advanced technology and propose an algorithm to be used over the current system so that lower signalling overheads and less delay, along with uninterrupted D2D communication, are guaranteed. We model and simulate our algorithm, comparing the results with mathematical models based on Markov theory. As in other similar communication systems, mobility management for D2D communication is yet to be explored fully. There are few research papers published so far. What we can say is that the intention of such systems in cellular networks are to enable lower latency, lower power consumption, less complexity and, last but not least, uninterrupted data connections. Our simulation results validate our proposed model and highlight D2D communication and its mobility issues. An essential element of our proposal is to estimate the user’s location. We can say that a mobility management system for D2D communication is hardly workable if the location of the users is not realisable. This dissertation also shows some latest techniques for estimating the direction of arrival (DOA) with mathematical models and simulation results. Smart antenna systems are proposed. It is possible to determine the location of a user by considering the uplink transmission system. Estimating the channel and actual path delay is also an important task, which might be done by using 1D uniform linear array (ULA) or 2D Uniform Rectangular (URA) array antenna systems. In this chapter, 1D ULA is described utilising some well-known techniques. The channel characteristics largely determine the performance of an end-to-end communication system. It determines the signal transformation while propagating through the channel between receivers and transmitters. Accurate channel information is crucial for both the transmitter and receiver ends to perform at their best. The ultimate focus of this part is to estimate the channel based on 2D parameter estimation. Uniform Rectangular Array (URA) is used to perform the 2D parameter estimation. It is possible to estimate azimuth and elevation of a source by using the URA model. The problem of mobility in this context has been investigated in few papers, with no reliable solutions as yet. We propose a unique algorithm for mobility management for D2D communications. In this dissertation, we highlight and explain the mobility model mathematically and analytically, along with the simulation of the Markovian model. A Markov model is essentially a simplified approach to describing a system that occupies a discrete state at any point in time. We also make a bridge between our mobility algorithm and a Markovian model

Deserts In The City: White Land And Regime Survival In The Gulf

The problem of ‘White Land’ (undeveloped urban land that is temporarily withheld from the market to increase land prices) emerged in Saudi Arabia as an unintended consequence of a survival strategy of land distribution to elites. Unfortunately, such a situation has become a daunting problem that kept the citizens of the kingdom remain unable to address their housing needs given ever-rising prices. To the contrary, despite its political, social and economic similarities, we do not witness citizens of the neighboring country of Oman suffering from the unaffordability of the housing market in their country. What does explain the variation in these two countries? In this dissertation, I argue that the prevalence of ‘White Land’ and the obstacles it poses to Saudi Arabia is an unintended outcome of a historical survival strategy to distribute land to the newly created elites. Saudi Arabia replaced its old established elites which had a considerable economic power with new ones that lack such an economic base. Such a historic decision by the government, and its land distribution strategy, resulted in the new elites’ domination of the real estate market to enrich themselves, which in turn put the greater citizens of the kingdom at risk. On the other hand, however, the old established Omani elites have not been replaced, which points to the fact that the Omani government did not face similar obstacles like what we see in Saudi Arabia. In this project, I explain that because the Omani elites’ economic base is not only dependent on land speculation, the impact on the housing market and the citizens’ ability to afford them has been very much minimal. Therefore, using this comparative case study, the dissertation further assesses why the Saudi government is unable to come up with a working policy to address the housing crisis. In arguing as well as explaining such a question, I have utilized case studies of the two countries using the comparative method and interviews that I conducted throughout my fieldwork in the two countries

Women and leadership: the case of women managers in Lebanon

La present tesi doctoral pretén examinar alguns dels reptes que continuen dificultant l'avanç de les dones cap a rols de lideratge, per què algunes dones no accepten tenir una cap dona i si les subordinades dones sempre donen suport a la seva cap. Així, aquesta tesi consta de tres articles de recerca empirica i un article de revisió bibliomètrica, que poden proporcionar un conjunt de treballs coherents relacionats amb les dones gestores libaneses. La revisió bibliompetrica investiga l'estat de la diversitat de gènere a les organitzacions i les seves implicacions en el rendiment dels subordinats. Amb aquesta finalitat, hem analitzat nombrosos treballs de recerca i hem identificat les barreres que poden impedir la inclusió de dones en els consells d'administració de les empreses, així com els impulsors que podrien millorar la representació de les dones als consells d'administració. També vam examinar alguns dels factors que influeixen en la satisfacció dels subordinats, com ara la satisfacció amb el seu lider, el rendiment del seu lifer i el seu propi rendiment. Pel que fa als tres articles de recerca empírica, el seu objectiu era examinar alguns dels reptes que continuen dificultant l'avenç de les dones libaneses a rols de lideratge, explorar algunes estratègies de vida laboral i personal que poden implementar els homes i les dones liders libaneses per equilibrar el seu treball i les activitats de treball i promoure els seus rols com a liders, així com investigar els reptes i les oportunitats de les empresàries libaneses.La presente tesis doctoral tiene como objetivo examinar algunos de los desafios que continúan obstaculizando el avance de las mujeres a roles de liderazgo, por qué algunas mujeres no aceptan tener una jefa y si las subordinadas siempre apoyan a su jefa. Por lo tanto, esta tesis consta de tres artículos de investigación empírica y un artículo de revisión bibliométrica, que pueden proporcionar un cuerpo de trabajo coherente relacionado con las mujeres directivas libanesas. La revisión bibliométrica investiga el estado de la diversidad de género en las organizaciones y sus implicaciones en el desempeño de los subordinados. Con este propósito, analizamos numerosos trabajos de investigación e identificamos las barreras que pueden impedir la inclusión de mujeres en los directorios corporativos, así como los impulsores que podrían mejorar la representación de las mujeres en los directorios. También examinamos algunos de los factores que influyen en la satisfacción de los subordinados, incluida la satisfacción con su líder, el desempeño del líder y su propio desempeño. En cuanto a los tres artículos de investigación empíricos, su objetivo era examinar algunos de los desafios que continúan obstaculizando el avance de las mujeres libanesas a roles de liderazgo, explorar algunas estrategias de trabajo y vida que pueden implementar los líderes libaneses hombres y mujeres para equilibrar su trabajo y las actividades laborales y promover sus roles como líderes, así como investigar los desafios y oportunidades de las mujeres empresarias libanesas.The present PhD thesis aims to examine some of the challenges that continue to hinder women advancement to leadership roles, why some women do not accept having a female boss and whether female subordinates are always supportive of their female boss. Thus, this thesis consists of three empirical research articles and one bibliometric review article, which can provide a coherent body of work related to Lebanese female managers. The bibliometric review investigates the status of gender diversity in organizations and its implications to subordinates' performance. With this purpose, we analyzed numerous research papers and identified the barriers that can impede the inclusion of women on corporate boards of directors, as well as the drivers that might improve females' representation on boards. We also examined some of the factors that influence subordinates' satisfaction including satisfaction with their leader, their leader's performance, and their own performance. As for the three empirical research articles, their aim was to examine some of the challenges that continue to hinder Lebanese women advancement to leadership roles, explore some work-life strategies that can be implemented by Lebanese men and women leaders to balance their work and non-work activities and promote their roles as leaders, as well as investigate Lebanese female entrepreneurs' challenges and opportunities

Consociationalism and corruption : an exploration of the consociational system's susceptibility to corruption.

Countries whose societies are fragmented, and which are in the process of transitioning to democracies, face the question of which political system best manages social conflict. Among those political systems that deal with conflict resolution in fragmented societies is consociationalism. This thesis argues that consociational political systems are prone to corruption, but, that specific factors in addition to the consociational arrangement itself activate the potential for corruption. An initial regression was conducted to establish the general relationship between consociationalism and corruption. A sample of 13 non-consociational countries was compared to 13 consociational ones. The regression test included consociationalism, political rights and civil liberties as independent variables. Corruption was the dependent variable. Results showed a significant relationship between consociational political systems and corruption. In addition, an increase in political rights was associated with a decrease in corruption. On the other hand, an increase in civil liberties was associated with an increase in corruption. These quantitative results were complemented by a qualitative case study of Lebanon's experience with consociationalism. The case study highlights how political corruption in Lebanon's consociational system has been aggravated by patterns of patron-client relationships that have long been present in Lebanese society

Latent Semantic Indexing (LSI) Based Distributed System and Search On Encrypted Data

Latent semantic indexing (LSI) was initially introduced to overcome the issues of synonymy and polysemy of the traditional vector space model (VSM). LSI, however, has challenges of its own, mainly scalability. Despite being introduced in 1990, there are few attempts that provide an efficient solution for LSI, most of the literature is focuses on LSI’s applications rather than improving the original algorithm. In this work we analyze the first framework to provide scalable implementation of LSI and report its performance on the distributed environment of RAAD. The possibility of adopting LSI in the field of searching over encrypted data is also investigated. The importance of that field is stemmed from the need for cloud computing as an effective computing paradigm that provides an affordable access to high computational power. Encryption is usually applied to prevent unauthorized access to the data (the host is assumed to be curious), however this limits accessibility to the data given that search over encryption is yet to catch with the latest techniques adopted by the Information Retrieval (IR) community. In this work we propose a system that uses LSI for indexing and free-query text for retrieving. The results show that the available LSI framework does scale on large datasets, however it had some limitations with respect to factors like dictionary size and memory limit. When replicating the exact settings of the baseline on RAAD, it performed relatively slower. This could be resulted by the fact that RAAD uses a distributed file system or because of network latency. The results also show that the proposed system for applying LSI on encrypted data retrieved documents in the same order as the baseline (unencrypted data)

Global Prediction of Wind Energy Market Strategy for Electricity Generation

Global warming and increasing electricity consumption trends in many parts of the world pose a serious challenge to most countries from a climate change and energy security perspective. Wind power is the only one that offers a mature technique, as well as promising commercial prospects, and is now generally applied in large-scale electricity generation. Continued technological improvements will assist to boost the on-shore and off-shore wind farms’ ability by improving micro turbine, enhancing reliability with predictive maintenance models. At the same time, as global and regional markets for wind power technologies grow, economies of scale are being reaped in manufacturing. With increased market scale, opportunities to improve the efficiency of supply chains arise. Technological improvements and cost reductions have led wind energy to become one of the most competitive options for new generation capacity. Wind energy still has significant potential for cost reduction. Indeed, by 2025, the global weighted average levelized cost of electricity (LCOE) of onshore and offshore wind could see declines of 26 and 35%, respectively. This chapter aims to provide an overview of the world wind energy market, current and forecasting development globally of wind energy, and LCOE historical growth Ffor wind energy

Economic Future of Concentrating Solar Power for Electricity Generation

Worldwide, the climate change is a major universal concern. CO2 is the main cause of international warming, and at least 85% emission results of CO2 came from conventional energy depleted sources (oil, natural gas and coal) for energy generation. Hence, renewable energy has been the focal point of most regulations of governments to aim at greenhouse gas reduced. In Egypt, greenhouse gas emissions from rural activities amount to some 25% of national greenhouse gas emissions, amounting to approximately 27 million t CO2 equivalent annually. Moreover, these emissions are supposed to increase rapidly in the coming decades, more than doubling in the next 15 years, as rural populations grow and activities become increasingly energy intensive. The Mediterranean region embraces Europe, North Africa and Middle East and has enormous potential in solar energy. It has abundant solar radiation, cheap land and high electricity demand, which could make this region the universal hub for concentrating solar power (CSP) generation. This chapter discusses the Egypt market potential of CSP. The chapter covers recent CSP trends and discusses in detail the CSP market development. The chapter aims to obtain the data sources to compare the CSP and levelized electricity cost. Enas Shouman presents a strategy for CSP plant market entrance in Egypt and a comparison between the electricity cost for Egypt model case and the cost evolution of CSP plants on the basis of expectations for the expansion as an international level. This chapter proposes a concept strategy for management CSP in Egypt. The chapter included two applied parts. The first part is to calculate the generating electricity cost from conventional power sources and its expansion in the future. Then, the second part will be followed by identifying the CSP cost and its growth in the future