Study of consensus protocols and improvement of the Federated Byzantine Agreement (FBA) algorithm

At a present time, it has been proven that blockchain technology has influenced to a great extent the way of human interaction in a digital world. The operation of the blockchain systems allows the peers to implement digital transactions in a Peer to Peer (P2P) network in a direct way without the need of third parties. Each blockchain determines different rules for the record of the transactions in the ledger. The transactions are inserted in blocks and each one, in turn, is appended to the chain (ledger) based on different consensus algorithms. Once blocks have been inserted in the chain, the consensus has been reached and the blocks with corresponding transactions are considered immutable. This thesis analyses the main features of the blockchain and how the consensus can be achieved through the different kinds of consensus algorithms. In addition, a detailed reference for Stellar and Federated Byzantine Agreement (FBA) consensus protocols is made in order to explain these algorithms, their limitations as well as their improvement. The development of a reputation mechanism is necessary to the improvement of above algorithms

Children\u27s perception of racial urban boundaries: a case study in Baton Rouge

This thesis explores the urban landscape of Baton Rouge through the eyes of the children. It seeks to understand the affect that planning and design decisions have on the lives of the children and the way that children perceive their urban environment. By examining the way others have studied the urban space I develop my own approach of exploring cities and understanding the urban life. Originally, I conduct informal observations in the study area and I generate my questions relating to the spatiality of the children. Secondly, I research to find possible design and planning decisions that may explain or justify the construction of the urban landscape as it is presented today, and specifically the presence of the urban boundaries. At the end, through children’s drawings and their words, I explore the way children understand the urban boundaries and the way these boundaries influence their spatiality. The evaluation of children’s perception of their urban environment stresses the importance that planning and design decisions and emphasizes designers’ power, through their work, in other people’s lives

Polar dependence

This thesis is an exploration of the relation between contrasting pairs and materials. For my thesis body of work I chose metal and soft materials to be my opposites. Through sculptures and prints I explore the feelings and thoughts their juxtaposition causes, bringing out both their strong and weak characteristics and showing their interdependence. Polar Dependence is what characterizes these two opposites , showing the need for these differences in our personal life and relationships. It asks the viewer to think beyond the ordinary use of these materials, to contemplate their qualities, the relationship between soft and strong, cold and warm, and how these are related to our qualities as humans. My intention is to show respect for both elements and to reflect the beauty that results when opposites come together. They need to co-exist because we need both

Even holding the same job title, men and women play different roles at work

Men spend more time in activities that increase wages, such as planning, negotiating and presenting, writes Aspasia Bizopoulo

Dimentional stability and microleakage of SMART dental composites in primary teeth

Dental composites were a revelation when they were introduced into the market. Even though they have kept evolving by becoming mechanically stronger, less technique sensitive and aesthetically appealing, they are still not easy to place and fail due to bacterial microleakage which leads to recurrent caries. Therefore, they have not been the staple material of choice for paediatric patients since they are not as reliable as preformed metal crowns long-term. AIMS AND OBJECTIVES: The aim of this project was to develop novel SMART composites which will target the paediatric patient. They have antibacterial polylysine and remineralising MCPM incorporated in them which could potentially address the bacterial microleakage problem of existing materials. They are self-etching and can be used as a bulk filling after soft caries removal. Good monomer conversion at depth and dimensional stability are essential for bulk filling and prevention of microleakage respectively and therefore the focus of this work. METHODS: An FTIR machine was used to measure the monomer conversion at 2 different sample depths (1mm, 2mm) with three different curing times (10s, 20s, 40s) in order to determine the effect of low versus high MCPM and PLS. In addition, mass and volume change was measured and shrinkage was calculated in order to determine the volumetric stability of the SMART composites. To assess microleakage, a dye test was performed in natural primary teeth drilled and directly filled with the SMART composite. This had the highest MCPM and PLS content. Three commercial materials which included Activa (following tooth etching) and two glass ionomer cements were used as comparators. RESULTS: Antibacterial polylysine and remineralising MCPM had negligible effect on monomer conversion. Volume change (2%) upon water sorption could help balanced polymerization shrinkage (3%). Microleakage of the SMART composite was equivalent to Activa but less than the glass ionomer cements. CONCLUSION: SMART composites good monomer conversion, volumetric stability, microleakage resistance and ease of placement should enable a more viable and predictable composite restorative paediatric option in the future

The Treatment of Myth in Modern Drama (1923-1950): Towards a Typology of Methods

Between the years 1923 and 1950, a great number of plays employed myth as subject matter or theme. The thesis examines this phenomenon in relation: a) to the modernist movement and its fascination with myth and mythological motifs, b) in relation to the efforts of modernist artists to find means appropriate to non-naturalistic modes of expression. Criticism up to now has surveyed myth-plays focusing on the thematic and ideological treatment of myths (psychoanalytic, religious, political, etc). This thesis proposes a new approach to this issue: it concentrates on techniques of incorporating myth in the structure of a play and on how myth functions within and through it. It identifies three prevailing techniques as methods. These methods form exclusive categories within the period under discussion. Therefore, plays are grouped according to method in order to explore a series of different dramaturgical strategies. Each of the three methods itself reflects a self-conscious attitude towards myth. Therefore, the thesis does not limit itself merely to investigating methods of incorporating myths into dramatic structures. It also examines the ideological substratum of those attitudes as they determine the discourses develope