The multidimensional (MD) modeling, which is the foundation of data warehouses (DWs), MD databases, and OnLine Analytical Processing (OLAP) applications, is based on several properties different from those in traditional database modeling. In the past few years, there have been some proposals, providing their own formal and graphical notations, for representing the main MD properties at the conceptual level. However, unfortunately none of them has been accepted as a standard for conceptual MD modeling.In this paper, we present an extension of the Unified Modeling Language (UML) using a UML profile. This profile is defined by a set of stereotypes, constraints and tagged values to elegantly represent main MD properties at the conceptual level. We make use of the Object Constraint Language (OCL) to specify the constraints attached to the defined stereotypes, thereby avoiding an arbitrary use of these stereotypes. We have based our proposal in UML for two main reasons: (i) UML is a well known standard modeling language known by most database designers, thereby designers can avoid learning a new notation, and (ii) UML can be easily extended so that it can be tailored for a specific domain with concrete peculiarities such as the multidimensional modeling for data warehouses. Moreover, our proposal is Model Driven Architecture (MDA) compliant and we use the Query View Transformation (QVT) approach for an automatic generation of the implementation in a target platform. Throughout the paper, we will describe how to easily accomplish the MD modeling of DWs at the conceptual level. Finally, we show how to use our extension in Rational Rose for MD modeling.

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Currently, the integration of technologies such as the Internet of Things and big data seeks to cover the needs of an increasingly demanding society that consumes more resources. The massification of these technologies fosters the transformation of cities into smart cities. Smart cities improve the comfort of people in areas such as security, mobility, energy consumption and so forth. However, this transformation requires a high investment in both socioeconomic and technical resources. To make the most of the resources, it is important to make prototypes capable of simulating urban environments and for the results to set the standard for implementation in real environments. The search for an environment that represents the socioeconomic organization of a city led us to consider universities as a perfect environment for small-scale testing. The proposal integrates these technologies in a traditional university campus, mainly through the acquisition of data through the Internet of Things, the centralization of data in proprietary infrastructure and the use of big data for the management and analysis of data. The mechanisms of distributed and multilevel analysis proposed here could be a powerful starting point to find a reliable and efficient solution for the implementation of an intelligent environment based on sustainability.

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Massive Open Online Courses (MOOCs) have a prominent role in achieving universal e-education, i.e. education offered via the internet to diverse learners around the world independently of their motivations, backgrounds, capacities, and limitations. Regrettably, current MOOCs platforms and contents are not accessible enough for all learners. This study presents the results of a systematic literature review on the combined field of accessible MOOCs that covers from the years 2008 to 2016. We followed a four-staged method than included a within-study and between-study literature analysis, and a descriptive synthesis. A total of 40 relevant studies was identified and mapped to eight research dimensions that form a lifecycle: problem characterization; needs identification; use of industry guidelines, specifications and standards; accessibility requirements specification; architectures; design strategies; verification of accessibility requirements compliance; and validation of user needs satisfaction. The results presented in this study give a head start to researchers interested in pursuing the combined field of accessible MOOCs, providers of MOOCs platforms and contents,

This article presents OO-HMethod, an extension of the OOMethod conceptual modelling approach to address the particulars associated with the design of web interfaces. It is based on the OO-Method class diagram, which captures the statics of the system. The design of the interface appearance and the navigation paths are driven by the user navigation requirements. To achieve its goal, OO-HMethod adds several navigation and interface constructs to the OO-Method conceptual model, which define the semantics suitable for capturing the specific functionality of web application interfaces. A new kind of diagram, the 'Navigation Access Diagram' (NAD) is introduced. All the concepts represented in the NAD are stored in a repository, and from there a functional interface is generated in an automated way. One of the main contributions of this paper is not the proposal of yet another method for web modelling but the extension of an existing conceptual modelling approach.

Today’s world demands more efficient learning models that allow students to play a more active role in their education. Technology is having an impact on how instruction is delivered and how information is found and share. Until very recently, the educational models encouraged memorization as an essential learning skill. These days, technologies have changed the educational model and access to information. Knowledge is available online, mostly free, and easily accessible. Reading, sharing, listening and, doing are currently necessary skills for education. Mobile devices have become a complete set of applications, support, and help for educational organizations. By conducting an analysis of the behavior and use of mobile devices on current students, efficient educational applications can be developed. Although there are several initiatives for the use of mobile learning in education, there are also issues linked to this technology that must be addressed. In this work, we present the results of a literature review of mobile learning; the findings described are the result of the analysis of several articles obtained in three scientific repositories. This work also lists certain issues that, if properly addressed, can avoid possible complications to the implementation of this technology in education.