SEISGAMA: A Free C# Based Seismic Data Processing Software Platform

Seismic reflection is one of the most popular methods in geophysical prospecting. Nevertheless, obtaining high resolution and accurate results requires a sophisticated processing stage. There are many open-source seismic reflection data processing software programs available; however, they often use a high-level programming language that decreases its overall performance, lacks intuitive user-interfaces, and is limited to a small set of tasks. These shortcomings reveal the need to develop new software using a programming language that is natively supported by Windows® operating systems, which uses a relatively medium-level programming language (such as C#) and can be enhanced by an intuitive user interface. SEISGAMA was designed to address this need and employs a modular concept, where each processing group is combined into one module to ensure continuous and easy development and documentation. SEISGAMA can perform basic seismic reflection processes. This ability is very useful, especially for educational purposes or during a quality control process (in the acquisition stage). Those processes can be easily carried out by users via specific menus on SEISGAMA’s main user interface. SEISGAMA has been tested, and its results have been verified using available theoretical frameworks and by comparison to similar commercial software

Performance Evaluation of a Wireless Network using a VoIP Traffic Generator on a Mobile Device

The problem of generating different patterns of traffic to emulate real user behaviour is receiving considerable attention with the construction of new and more complex network architectures. The theoretical modelling of waveforms or signals that flow through networks is valuable in a variety of scenarios including performance analysis and the design of communication systems. In the literature, many computer-based performance evaluation tools have been discussed. However, these tools lack the ability to run on affordable technologies such as mobile phones. The fundamental contribution of this work is the design of a traffic generating tool called MTGawn which is able to run on a mobile device. Design Science Research was the research methodology used for the design and deployment of a prototype of the proposed system. VoIP traffic was emulated using an implementation of well-known real time transport protocols such as RTP and cRTP, and parameterization was defined by using three codecs namely: G.711, G.723, and G.729. An evaluation was performed in a laboratory wireless network testbed and preliminary results were collected and analysed. The results of the experiments show that such a measuring instrument can be deployed on a mobile phone. More experiments are being done to ensure the accuracy of the data and also to compare the results with that of computer-based systems. Furthermore additional functionalities, similar to the functionality found on the computer-based open source tools, are being added to the mobile tool.Telkom, Cisco, Aria Technologies, THRIPDepartment of HE and Training approved lis

Fault-tolerance and malleability in parallel message-passing applications

[Resumo] Esta tese explora solucións para tolerancia a fallos e maleabilidade baseadas en técnicas de checkpoint e reinicio para aplicacións de pase de mensaxes. No campo da tolerancia a fallos, esta tese contribúe melloraudo o factor que máis incrementa a sobrecarga, o custo de E/S no envorcado dos ficheiros de estado, propoñendo diferentes técnicas para reducir o tamaño dos ficheiros de checkpoint. Ademais, tamén se propón un mecanismo de migración de procesos baseado en checkpointing. Esto permite a migración proactiva de procesos desde nodos que están a piques de fallar, evitando un reinicio completo da execución e melloraudo a resistencia a fallos da aplicación. Finalmente, esta tese presenta unha proposta para transformar de forma transparente aplicacións MPI en traballos maleables. Esto é, programas paralelos que en tempo de execución son capaces de adaptarse so número de procesadores dispoñibles no sistema, conseguindo beneficios, como maior productividade, mellor tempo de resposta ou maior resistencia a fallos nos nodos. Todas as solucióru; propostas nesta tese foron implementadas a nivel de aplicación, e son independentes da arquitectura hardware, o sistema operativo, a implementación MPI usada, e de calquera framework de alto nivel, como os utilizados para o envío de traballos.[Resumen] Esta tesis explora soluciones de tolerancia a fallos y maleabilidad basadas en técnicas de checkpoint y reinicio para aplicaciones de pase de mensajes. En el campo de la tolerancia a fallos, contribuye mejorando el factor que más incrementa la sobrecarga, el coste de E/S en el volcado de los ficheros de estado, proponiendo diferentes técnicas para reducir el tamaño de los ficheros de checkpoint. Ademós, también se propone nn mecanismo de migración de procesos basado en checkpointing. Esto permite la migración proactiva de procesos desde nodos que están a punto de fallar, evitando un reinicio completo de la ejecución y mejorando la resistencia a fallos de la aplicación. Finalmente, se presenta una propuesta para transformar de forma transparente aplicaciones MPI en trabajos maleables. Esto es, programas paralelos que en tiempo de ejecución son capaces de adaptarse al número de procesadores disponibles en el sistema, consiguiendo beneficios, como mayor productividad, mejor tiempo de respuesta y mayor resistencia a fallos en los nodos. Todas las soluciones propuestas han sido implementadas a nivel de aplicación, siendo independientes de la arquitectura hardware, el sistema operativo, la implementación MPI usada y de cualquier framework de alto nivel, como los utilizados para el envío de trabajos.[Abstract] This Thesis focuses on exploring fault-tolerant and malleability solutions, based on checkpoint and restart techniques, for parallel message-passing applications. In the fault-tolerant field, tbis Thesis contributes to improving the most important overhead factor in checkpointing perfonnance, that is, the I/O cost of the state file dumping, through the proposal of different techniques to reduce the checkpoint file size. In addition, a process migration based on checkpointing is also proposed, that allows for proactively migrating processes fram nades that are about to fail, avoiding the complete restart of the execution and, thus, improving the application resilience. Finally, this Thesis also includes a proposal to transparently transform MPI applications into malleable jobs, that is, parallel programs that are able to adapt their execution to the number of available processors at runtime, which provides important benefits for the end users and the whole system, such as higher productivity and a better response time, or a greater resilience to node failures. All the solutions proposed in this Thesis have been implemented at the application-level, and they are independent of the hardware architecture, the operating system, or the MPI implementation used, and of any higher-level frameworks, such as job submission frameworks