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NoSQL databases are capable of storing and processing big data which is characterized by various properties such as volume, variety and velocity. Such databases are used in a variety of user applications that need large volume of data which is highly available and efficiently accessible. But they do not enforce or require strong data consistency nor do they support transactions. This paper investigates into the transaction processing in consistency-aware applications hosted on MongoDB and Riak which are two representatives of Document and Key-Value NoSQL databases, respectively. It develops new transaction schemes in order to provide NoSQL databases with transactional facilities as well as to analyze the effects of transactions on data consistency and efficiency in user’s applications. The proposed schemes are evaluated using the YCSB + T benchmark which is based on Yahoo! Cloud Services Benchmark (YCSB). Experimental results show that using the proposed schemes, strong consistency can be achieved in MongoDB and Riak without severely affecting their efficiency. We also conduct experiments in order to analyse the level of consistencyof MongoDB and Riak transactional systems.

Web services (WS) transactions are important in order to reliably compose distributed and autonomous services into composite web services and to ensure that their execution is consistent and correct. But such transactions are generally complex and they require longer processing time, and manipulate critical data. Thus various techniques have been developed in order to perform quality assessment of WS transactions in terms of response time efficiency, failure recovery and throughput. This paper focuses on the testing aspect of WS transactions - another key quality issue that has not been examined in the literature. Accordingly it proposes multi-dimensional criteria for testing the WS transactions. The proposed criteria have the potential to capture the behaviour of WS transactions and to analyse and classify the possible (failure) situations that effect the execution of such transactions. These criteria are used to generate various test cases and to provide (WS transactions) ! tester with flexibility of adjusting the method in terms of test efforts and effectiveness. The proposed criteria have been designed, implemented and evaluated through a case study and a number of experiments have been performed. The evaluation shows that these criteria have the capability to effectively generate test cases for testing WS transactions as well as enable tester to decide on the trade-off between test efforts and the quality.

La gestión de proyectos se puede considerar todavía como un arte en el cual el uso de la información cuantitativa tiende a fomentar un enfoque más riguroso de la gestión. En este trabajo presentamos la estructura y los elementos principales de un entorno de entrenamiento para directores de proyectos. El objetivo del sistema es proporcionar una estructura uniforme para que se puedan incorporar nuevas técnicas en la estructura de forma gradual. El sistema reúne y almacena los datos del proyecto real y del simulado e implementa diferentes técnicas basadas en aprendizaje automático, modelado dinámico, monitorización de proyectos, etc. El propósito básico de este trabajo es el de presentar un entorno que facilite la toma de decisiones integrando diferentes técnicas y líneas de investigación.

La gestión de proyectos se puede considerar todavía como un arte en el cual el uso de la información cuantitativa tiende a fomentar un enfoque más riguroso de la gestión. En este trabajo presentamos la estructura y los elementos principales de un entorno de entrenamiento para jefes de proyectos. El objetivo del sistema es proporcionar una estructura uniforme para que se puedan incorporar nuevas técnicas en la estructura de forma gradual. El sistema reúne y almacena los datos del proyecto real y del simulado e implementa diferentes técnicas basadas en aprendizaje automático, modelado dinámico, monitorización de proyectos, etc. El propósito básico de este trabajo es hacer que la toma de decisiones esté apoyada por la integración de diferentes fuentes de información.