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Time Series Database (TSDB), is a particular type of data repository. TSDBs are capable of diverse functionalities regarding operations on time series data and are developed using different technologies. A large number of TSDB solutions, available both as open source and commercial software, has emerged in the last years. Selecting the proper TSDB is a challenging endeavour for a potential enterprise client. In this paper, a set of open-source TSDBs which includes InfluxDB, Graphite, RRDTool, Prometheus, OpenTSDB and TimescaleDB-has been selected for analysis, evaluation and ranking. A comparison of TSDBs implies the establishment of a set of attributes. A set of quantitative and qualitative attributes which have different scales and units of measure has been selected. The problem of selecting or ranking TSDBs evaluated in this paper with a set of attributes is a Multi-Attribute Decision Making problem (MADM). For solving the TSDBs evaluation, analysis and selection a multi-attribute TSDBs maturity model has been proposed. The model for the selected TSDBs set and for the 18 attributes, 10 quantitative and 8 qualitative, has been validated. The model for all the attributes, both quantitative and qualitative, has been solved and, finally, a comparison between the obtained rankings has been made. The comparison of the ranks obtained shows that the leading TSDB is InfluxDB.

In this paper we have presented the main characteristics of the most important reference architectures designed for the cloud computing environment. Specifically, we have introduced the proposed architectures of the worldwide cloud computing companies like Cisco, IBM and VMware and we also had a look at the National Institute of Standards and Technology (NIST) reference architecture which is the starting point for all proposed architectures in the field. As one would expect, the provider dependent reference architectures are written is such a way to suit the services and products of the company, while NIST's architecture is a more general model with more comprehensive architectural details that we highlighted in this article. In the end of the article we draw out some conclusions regarding the existing reference architectures for cloud computing.

This paper covers the process of developing and populating the TransNEW international database designed to assist management from transport research organizations in providing the means for research to support decisions. The process ranges from database and tables creation to the setting up of relationships between database elements and web forms so that database fields may be populated and the information can be easily managed. The next phase involved inputting information gathered by TransNEW Partners. The described processes and procedures involved choosing the appropriate platform, and designing an information management system for this database.

Automation in testing user interfaces is a prerequisite for overcoming the major weaknesses of manual testing, such as time consumption, not being able to reproduce the sequence that generates a bug or the tendency to repeat only the successful steps. Continuous testing represents an important step in the agile software development cycle because any features and changes added to the code need to be checked before their propagation to production environment. Manually testing is a resource and time-consuming process thus the solution would be to make the entire workflow from committing a change to publishing a new release completely automated. The solution proposed within this paper is a framework for automated code testing and bug prevention that relies on Selenium, a framework supporting also headless testing, integrated with a Continuous Integration (CI) server such as Jenkins.