The last years, huge bundles of information are extracted by computational systems and electronic devices. To exploit the derived amount of data, new innovative algorithms must be employed or the established ones maybe changed. One of the most fascinating and productive techniques, in order to locate and extract information from data repositories is clustering, and DBSCAN is a successful density based algorithm which clusters data according its characteristics. However, its main disadvantage is its severe computational complexity which proves the technique very inadequate to apply on big datasets. Although DBSCAN is a very well studied technique, a fully operational parallel version of it, has not been accepted yet by the scientific community. In this work, a three phase parallel version of DBSCAN is presented. The obtained experimental results are very promising and prove the correctness, the scalability, and the effectiveness of the technique.

This work is devoted to the portfolio project management problem and more precisely it is focused on IT portfolios' management. The problem is modelled as a multi-purpose job shop problem. Contemporary organisations such as IT companies define a careful planning to perform a set of projects that share common resources. These projects must, therefore, be handled concurrently. In this study we reviewed the literature and developed a system based on a multi-objective problem model. We use recurrent neural network (RNN) technique to look for optimal or near-optimal solutions to the derived optimisation problem. We first apply a greedy algorithm to find an initial feasible solution. This solution is then fed to the RNN. We implemented our approach and evaluated it on some well known benchmarks. The experimental results obtained were very promising.

Internet addiction is the most modern form of addiction and belongs to behavioral addictions. The term appeared in 1996 and spread very quickly all over the world, especially among teenagers and young people. Many users escape the formal use of the Internet and easily lose control of the situation. The article aims to deal with the university students’ addiction to Internet and social media. It is a fact that most young people spend valuable time on the Internet without knowing the negative impact this engagement may have. For this purpose, a questionnaire based on the Internet Addiction Test was formulated, in order to answer a number of questions about Internet addiction, the consequences and causes of this phenomenon, the ways of dealing with the problem, the indications (information) and statistical data available for Greece, etc. The results obtained will be very useful and can be used by researchers to shape the profile of new and future uses, regarding the impact of internet use on professional life and development of young people, but also in dealing with social phenomena and adaptation problems.

The last years, huge masses of data are produced or extracted by computational systems and independent electronic devices. To exploit this resource, novel methods must be employed or the established ones may be altered in order to confront the issues that arise. One of the most fruitful techniques, in order to locate and use information from data sources is clustering, and k-means is a successful representative algorithm which clusters data according specific characteristics. However, its main disadvantage is the computational complexity which proves the techniques very unproductive to apply on big datasets. Although k-means is a very well studied technique, a fully operational distributed version combining the multi-core power of today machines, have not been accepted yet by the scientific community. In this work, a three phase distributed/multi-core version of k-means is presented. The obtained experimental results are very promising and prove the correctness, the scalability, and the effectiveness of the proposed technique.

Project management methodologies are geared towards managing individual projects. However, modern project-oriented firms execute more than one project at a time. This is a common characteristic in the service sector, like telecommunication companies, which run a bundle of projects concurrently. Hence, project scheduling gradually becomes project portfolio scheduling. It must be underlined that projects within a given portfolio are usually interconnected with relationships and dependencies and share common resources. Maximizing the overall value generated from project completion and operation is a main objective in portfolio scheduling. A modification of the IFM approach is used in order to confront this scheduling problem. A set of problem instances is generated in order to instigate a comparison study. The obtained results are quite promising and the method seems to scale well regarding the size of the project portfolio.