Masters of Science / In this study, a traffic generator software package namely MTGawn was developed to run packet generation and evaluation on a mobile device. The call generating software system is able to: simulate voice over Internet protocol calls as well as user datagram protocol and transmission control protocol between mobile phones over a wireless network and analyse network data similar to computer-based network monitoring tools such as Iperf and D-ITG but is self-contained on a mobile device. This entailed porting a ‘stripped down’ version of a packet generation and monitoring system with functionality as found in open source tools for a mobile platform. This mobile system is able to generate and monitor traffic over any network interface on a mobile device, and calculate the standard quality of service metrics. The tool was compared to a computer–based tool namely distributed Internet traffic generator (D-ITG) in the same environment and, in most cases, MTGawn reported comparable results to D-ITG. The important motivation for this software was to ease feasibility testing and monitoring in the field by using an affordable and rechargeable technology such as a mobile device. The system was tested in a testbed and can be used in rural areas where a mobile device is more suitable than a PC or laptop. The main challenge was to port and adapt an open source packet generator to an Android platform and to provide a suitable touchscreen interface for the tool. ACM Categories and Subject Descriptors B.8 [PERFORMANCE AND RELIABILITY] B.8.2 [Performance Analysis and Design Aids] C.4 [PERFORMANCE OF SYSTEMS] Measurement techniques, Performance attributes

Este trabalho consiste na implementação de um gerador gráfico que propiciará a discretização de estruturas lineares formadas pela união de subestruturas. Estruturas com muitos graus de liberdade serão calculadas através da sua divisão em subestruturas, permitindo uma significativa diminuição nas dimensões das matrizes envolvidas. A aplicação da técnica das subestruturas irá permitir, também, a análise de diferentes tipos estruturais interligados, como pórticos e treliças, compatibilizando os deslocamentos comuns nos nós de união. O gerador gráfico irá tratar as subestruturas como sendo entidades próprias, isoladas, conferindo a elas características que possibilitarão transformações gráficas durante a sua edição. Pretende-se que o gerador gráfico condicione a uma melhor organização na discretização estrutural, como também venha a facilitar todo o processo de lançamento da estrutura. Do mesmo modo, cria condições para submeter adequadamente os resultados de cálculo a outros programas, como os de dimensionamento e detalhamento. / This work consists of the implementation of a graphic generator that will propitiate the discretization of lineal structures formed by the substructures union. Structures with many degrees of freedom will be calculated through its division in substructures, allowing a significant decrease in the dimensions of the involved matrix. The application of the technique of the substructures will allow, also, the analysis of different interlinked structural types, as frames and trusses, based on the compatibility of the common displacements in the union knots. The graphic generator will treat the substructures as being own, isolated entities, checking them characteristics that will facilitate graphic transformations during its edition. It is intended that the graphic generator conditions to a better organization in the structural discretization, as well as come to facilitate the whole process of release of the structure. In the same way, it creates conditions to submit the calculation results appropriately the other programs, as the one of design and details.

This thesis presents a method of detecting electrical islands in low voltage distributed generator networks by measuring negative sequence impedance differences between islanded and utility connections. Extensive testing was conducted on a commercial building and 25 kV distributed generator fed network by measuring naturally occurring and artificially injected negative sequence components. Similarly, this technique was tested using the IEEE 399-1990 bus test case using the EMTP software. The practical measurements have been matched to simulations where further system performance characteristics of detecting power system islands has been successfully demonstrated. Measured results indicate that unbalanced load conditions are naturally occurring and readily measurable while deliberately unbalanced loads can increase the accuracy of negative sequence impedance islanding detection. The typically low negative sequence impedance of induction motors was found to have only a small effect in low voltage busses, though large machines can effect the threshold settings. Careful placement of the island detector is required in these situations. The negative sequence impedance measurement method is an improvement on previous impedance measurement techniques for islanding detection due to its accuracy, and distinctly large threshold window which have challenged previous impedance based islanding detection techniques. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

In this thesis we investigate, implement and evaluate a solution for introducing the TransmissionControl Protocol (TCP) into the software of a load generator. The load generator is a simulator usedfor simulating end-user generated activities in the Universal Mobile Telecommunication System(UMTS) network. The purpose of simulating traffic on the network is in this case to verify thefunctionality and robustness of the Radio Network Controller (RNC) node within the UMTSnetwork.TCP is a protocol that provides reliable data transfer over unreliable underlying networkprotocols. It is used as the main transport protocol of the Internet, thus it is also used in the UMTSnetwork in order to provide connectivity for user equipment, such as 3G mobile phones, to servicesover the Internet. For the load generator to be able to produce more realistic traffic scenarios is itdesirable to give it the ability to use TCP.This thesis presents a solution of the problem where an open-source implementation of the TCPfunctionality was chosen, ported to the running platform of the load generator and then tested in asimulated test environment. The choice of the open source implementation of TCP was made byperforming an investigation of available options. In the investigation an open source TCP/IP stackcalled lwIP was chosen. lwIP was then ported to the running platform of the load generator bywrapping and modify the source code. The tests of the ported TCP implementation were made in asimulated test environment with focus on testing basic TCP functionality. The tests showed that theTCP implementation produced provided the basic functionality that was asked for.

In today’s fast paced changing technology world, it is essential to adapt the new technologies and standards in order to stay compliant with the market. Software development is one of those key areas that have been growing highly fast and thus the need for staying up to date needs to be acknowledged by everyone in the area. The technology focused in this project is called ModelicaML[1] which is an integrated system modeling environment based on standardized languages such as UML[2] and Modelica[3]. Modelica Modeling Language (ModelicaML) is a graphical modeling language used for the description of time-continuous and time-discrete/event-based system dynamics. Currently, a ModelicaML code generator – that generates Modelica code from UML models – is implemented using the old Acceleo framework[4]. Within this thesis, the ModelicaML code generator was re-factored and implemented by using the latest Acceleo version 3.X[5]. The differences between the old and new Acceleo framework was also given an evaluation in the study in order to provide a hint of its future use for further improvements of the code generator.

Main objective of this thesis is to extend existing functionality of Integrated Development Environment (IDE) BlueJ with possibility of working with streams in an interactive mode. This new functionality helps to falicitate and improve teaching of programming within the First Architecture methodology. First part of this thesis deals with IDE BlueJ and discusses problematic software con-structions which don´t have sufficient support in interactive mode. Main focus is put on streams. Another part of this thesis suggests possible options for extension which should be integrated to the existing functionality. Following part focuses on analysis of the proposed changes and final part discusses implementation itself and describes author´s process of realization.

[pt] Muitas centrais nucleares do tipo PWR utilizam vapor produzido em geradores de vapor do tipo tubos em U invertido, com recirculação interna natural, nos quais o fluido primário escoa internamente aos tubos e o secundário, entre os tubos e a carcaça. No presente trabalho, é desenvolvido um modelo de simulação termohidráulica, para regime permanente, de tais geradores de vapor, considerando-se o escoamento secundário divididas em duas partes, individualmente homogêneas, e com troca de calor e massa entre elas. O título da mistura bifásica que alimenta a turbina é fixado e a pressão da água de alimentação é determinada. Baseado neste modelo, desenvolveu-se o programa GEVAP, em linguagem Fortran-IV. O modelo é aplicado ao gerador de vapor da central Angra II e os resultados obtidos são comparados com dados de projeto da KWU, sendo considerados satisfatórios. / [en] Many PWR power plants use steam produced in steam generators with inverted U tubes with natural internal recirculation, in which the primary fluid flows inside the tubes and the working fluid, between the tubes and the shell. In the present work, it is developed a model of termohidraulic simulation, for steady state, considering the scondary flow divided in two parts individually homogeneous, and with heat and mass transferences between them. The quality of the two-phase mixture that is fed to the turbine is fixed and, based on this value, the feedwater pressure is determined. The recirculation ratio is intrinscally determined. Based on this model is applied to the steam generator of the Angra II nuclear power palnt and the results are compared with KWU’s design parameters, being considered satisfactory.

The master's thesis is focused on the design and implementation of a tool for generating configuration named Ansible. The result of using this tool is generated configuration, which contains random values chosen according to specified parameters and it was deployed on a virtual testing infrastructure. The theoretical part describes approaches of network automation in the process of deploying and configuration of network devices called Infrastructure as code. It also describes programme Ansible, which will be using the output of the implemented tool. The practical part of the thesis is focused on designing the functionality and internal structure of the tool, implementation of the tool and testing implemented tool as well as generated configuration.

The work deals with design, simulation and preparation of laboratory preparation. The main aim of the thesis is to design and implement a simple noise generator, signal sources, mixer and phase lock loop for teaching purposes.

A combined cycle is one of the thermal cycles used in thermal power plants. It consists of a combination of a gas and a steam turbine, where the waste heat from the gas turbine is used for steam generation in the heat recovery steam generator. The aim of the diploma thesis was the conceptual design of a combined cycle electricity source and the balance calculation of the cycle. The calculation is based on the thermodynamic properties of the substances and the basic knowledge of the Brayton and Rankin-Clausius cycle. The result is the amount and parameters of air, flue gases, and steam/water in individual places and the technological scheme of the source, in which these parameters are listed.