Doctor of Philosophy

dissertationMinimally invasive thermal therapy under Magnetic Resonance Imaging (MRI) guidance is becoming popular with several applications in the process of getting FDA approval. The ability to determine in near real-time the temperature map of a tumor and its surrounding tissue makes MR thermometry very attractive and well suited for thermal treatment. The proton resonance frequency shift (PRF) is currently the gold standard method for temperature monitoring using MRI. However, its incapacity to measure temperature in fatty tissue limits the scope of its applicability. The spin lattice relaxation time T1, on the other hand, has shown good temperature sensitivity and works well in all types of tissues. In this dissertation, we have addressed a number of challenges currently affecting MRI thermometry. A non-CPMG Turbo Spin Echo (TSE) sequence has been implemented to monitor the temperature rise due to the high RF power deposition inherent to this sequence at high field (3T and higher). This new implementation allows TSE sequences to be used safely without altering their high contrast properties which make them appealing in clinical settings. Tissue damage assessment during thermal therapy is critical for the safety of the patient. We have developed a new hybrid PRF-T1 sequence that has the capability to provide simultaneously in near real-time the temperature map and T1 information, which is a good indication of the state of the tissue. The simplicity and the real-time capability of the newly developed sequence make it an ideal tool for tissue damage assessment. Temperature monitoring during thermal therapy in organs with large fat content have been hindered by the lack of an MRI thermometry method that can provide simultaneous temperature in fat and aqueous tissue. A new sequence and acquisition scheme have been developed to address this issue. In sum, this dissertation proposed several pulse sequence implementation techniques and an acquisition scheme to overcome some of the limitations of MR thermometry

Transmission des fluctuations et calcul des prix de parité à l’importation du riz en et du maïs en Guinée

Calculation of maize and rice parity prices in Guinea.food security, Guinea, parity prices, markets, Agricultural and Food Policy, Community/Rural/Urban Development, Food Security and Poverty, International Development, International Relations/Trade, Marketing, q11, q18,

The impact of ESG factors integration on financial performances of Real Estate investment trusts (REITs) in FRANCE

This study demonstrates how ESG is valued in REITs. Between 2011and 2020, collecting ESG ratios from the IEIF SIIC France index, and see if the high rated ESG companies out perform the market. The findings, show that this association of multi-factor is shifting toward a favorable performance for companies with a high ESG ratios. Furthermore, when comparing listed real estate to the market, it indicates that ESG has a mixed influence. According to the findings, the price of ESG varies between REITs and the market. The link between ESG and return on listed real estate has gotten little attention. This thesis demonstrates the importance of considering the individual influence, as well as the fact that previous market studies cannot simply be applied to REIT

Toward an expert project management system

The purpose of the research effort is to prescribe a generic reusable shell that any project office can install and customize for the purposes of advising, guiding, and supporting project managers in that office. The prescribed shell is intended to provide both: a component that generates prescriptive guidance for project planning and monitoring activities, and an analogy (intuition) component that generates descriptive insights of previous experience of successful project managers. The latter component is especially significant in that it has the potential to: retrieve insights, not just data, and provide a vehicle for expert PMs to easily transcribe their current experiences in the course of each new project managed

Mapping Digital Media: Poland

The Mapping Digital Media project examines the global opportunities and risks created by the transition from traditional to digital media. Covering 60 countries, the project examines how these changes affect the core democratic service that any media system should provide: news about political, economic, and social affairs.Digital switch-over of terrestrial broadcasting in Poland may still be almost a year away, but the lead-up and preparations to it have shed light on the most entrenched problems facing the country's public service broadcasters.This study of the impact of digitization on Polish media highlights the delays in digitization caused by political infighting; the lack of technical and financial assistance to ensure that the most vulnerable members of society benefit from digitization and new media; and the funding crisis afflicting public broadcasting. The political and economic position of the public broadcaster is critical in the digitization of broadcasting in Poland, both because of its continued—albeit diminishing—role in the media market, and because of its extensive involvement in the preparations for the switch-over.The authors of this report assess that the initiatives to inform the public about how digitization will affect them have been insufficient. Appropriate provisions should swiftly be put in place. Other major recommendations include a revision of spectrum allocation criteria to improve access for those "third way" broadcasters such as religious, educational, civil society or local government outlets, and the need for a durable solution to the public broadcasting funding crisis

WISP: a wireless information security portal

M.Sc.Wireless networking is a fairly new technology that is important in information technology (IT). Hotels, Airports, Coffee shops, and homes are all installing wireless networks at a record pace, making wireless networks the best choice for consumers. This popularity of wireless networks is because of the affordability of wireless networks devices, and the easy installation [11]. In spite of the popularity of the wireless networks, one factor that has prevented them from being even more widespread can be summed up in a single word: security. It comes as no surprise that these two – wireless and security – converge to create one of the most important topics in the IT industry today [11]. Wireless networks by nature bring about new challenges unique to its environment. One example of these new challenges is: “Signal overflow beyond physical walls”, and with these kinds of new challenges unique to wireless networks, we have new security risks. Hence wireless networks lend themselves to a host of attack possibilities and risks. That is because wireless networks provide a convenient network access point for an attacker, potentially beyond the physical security controls of the organization [7]. Therefore it is challenging for managers to introduce wireless networks and properly manage the security of wireless networks, Security problems of wireless networks are the main reason for wireless networks not being rolled out optimally [1]. In this dissertation, we aim to present to both specialist and non–specialists in the IT industry the information needed to protect a wireless network. We will first identify and discuss the different security requirements of wireless networks. After that we shall examine the technology that helps make wireless networks secure, and describe the type of attacks against wireless networks and defense techniques to secure wireless networks. The research will concentrate on wireless LANs (Local Area Networks), and leading wireless LAN protocols and standards. The result of the research will be used to create WISP (A Wireless Information Security Portal). WISP will be a tool to support the management of a secure wireless network, and help assure the confidentiality, integrity, and availability of the information systems in a wireless network environment

Tax Potential and Tax Effort: An Empirical Estimation for Non-resource Tax Revenue and VAT’s Revenue

Taxation is one of the main components of a country’s fiscal space. Its internal origin and the accountability it creates between rulers and populations make it a key element in financing public expenditure. Tax capacity differs between countries and depends on structural factors. A number of empirical studies attempted to determine countries’ overall tax potential and tax effort (Lotz and Morss, 1967; Stotsky and Wolde Mariam, 1997; Fenochietto and Pessino, 2013). However, the methodologies used tend to underestimate or overestimate countries’ tax potential and thereby their tax effort. The purpose of this study is to better assess countries’ non-resource tax potential and VAT’s tax potential independently using a more appropriate method. It is in line with the study of Brun et al. (2014) and rests on a large sample of developing countries over the period 1980/2014. We first employ the previous models and discuss about their shortcomings, after we use the stochastic frontier model of Kumbhakar, Lien and Hardaker (2014). This model allows to disentangle the overall tax effort into a persistent tax effort due to policy economy decisions and a time-varying tax effort relating to tax administration efficiency. The results are more realistic. Low income countries have higher tax effort along the period even if their tax effort decline at the end of period on the opposite of resource depending countries. In fact, the latter characterized by lower tax effort compared to non-resource countries improved consequently the efficiency of their system since 2010. The results also suggest that inefficiency in taxation depends more on policy decisions than on tax administration performance