117,079 research outputs found
Towards Conceptual Multidimensional Design in Decision Support Systems
International audienceMultidimensional databases support efficiently on-line analytical processing (OLAP). In this paper, we depict a model dedicated to multidimensional databases. The approach we present designs decisional information through a constellation of facts and dimensions. Each dimension is possibly shared between several facts and it is organised according to multiple hierarchies. In addition, we define a comprehensive query algebra regrouping the more popular multidimensional operations in current commercial systems and research approaches. We introduce new operators dedicated to a constellation. Finally, we describe a prototype that allows managers to query constellations of facts, dimensions and multiple hierarchies
Using Ontologies for the Design of Data Warehouses
Obtaining an implementation of a data warehouse is a complex task that forces
designers to acquire wide knowledge of the domain, thus requiring a high level
of expertise and becoming it a prone-to-fail task. Based on our experience, we
have detected a set of situations we have faced up with in real-world projects
in which we believe that the use of ontologies will improve several aspects of
the design of data warehouses. The aim of this article is to describe several
shortcomings of current data warehouse design approaches and discuss the
benefit of using ontologies to overcome them. This work is a starting point for
discussing the convenience of using ontologies in data warehouse design.Comment: 15 pages, 2 figure
THE DESIGN AND IMPLEMENTATION OF OLAP SYSTEM. CASE STUDY â UNIVERSITY RESEARCH
The aim of this study is to show that multidimensional modelling of existing data in organizations, depending on the topics of interest of managers and multidimensional view of data. It may also provide an effective informational support of managers in decision making, regardless of field of activity. To prove it, this study will design a data model and an OLAP multidimensional analysis of scientific research in education university.OLAP, hyper - cube, n-dimensional cube, conceptual model
Making space for proactive adaptation of rapidly changing coasts: a windows of opportunity approach
Coastlines are very often places where the impacts of global change are felt most keenly,
and they are also often sites of high values and intense use for industry, human habitation, nature
conservation and recreation. In many countries, coastlines are a key contested territory for planning
for climate change, and also locations where development and conservation conflicts play out. As
a âtest bedâ for climate change adaptation, coastal regions provide valuable, but highly diverse
experiences and lessons. This paper sets out to explore the lessons of coastal planning and
development for the implementation of proactive adaptation, and the possibility to move from
adaptation visions to actual adaptation governance and planning. Using qualitative analysis of
interviews and workshops, we first examine what the barriers are to proactive adaptation at the coast,
and how current policy and practice frames are leading to avoidable lock-ins and other maladaptive
decisions that are narrowing our adaptation options. Using examples from UK, we then identify
adaptation windows that can be opened, reframed or transformed to set the course for proactive
adaptation which links high level top-down legislative requirements with local bottom-up actions.
We explore how these windows can be harnessed so that space for proactive adaptation increases
and maladaptive decisions are reduced
Benchmarking Summarizability Processing in XML Warehouses with Complex Hierarchies
Business Intelligence plays an important role in decision making. Based on
data warehouses and Online Analytical Processing, a business intelligence tool
can be used to analyze complex data. Still, summarizability issues in data
warehouses cause ineffective analyses that may become critical problems to
businesses. To settle this issue, many researchers have studied and proposed
various solutions, both in relational and XML data warehouses. However, they
find difficulty in evaluating the performance of their proposals since the
available benchmarks lack complex hierarchies. In order to contribute to
summarizability analysis, this paper proposes an extension to the XML warehouse
benchmark (XWeB) with complex hierarchies. The benchmark enables us to generate
XML data warehouses with scalable complex hierarchies as well as
summarizability processing. We experimentally demonstrated that complex
hierarchies can definitely be included into a benchmark dataset, and that our
benchmark is able to compare two alternative approaches dealing with
summarizability issues.Comment: 15th International Workshop on Data Warehousing and OLAP (DOLAP
2012), Maui : United States (2012
Database Systems - Present and Future
The database systems have nowadays an increasingly important role in the knowledge-based society, in which computers have penetrated all fields of activity and the Internet tends to develop worldwide. In the current informatics context, the development of the applications with databases is the work of the specialists. Using databases, reach a database from various applications, and also some of related concepts, have become accessible to all categories of IT users. This paper aims to summarize the curricular area regarding the fundamental database systems issues, which are necessary in order to train specialists in economic informatics higher education. The database systems integrate and interfere with several informatics technologies and therefore are more difficult to understand and use. Thus, students should know already a set of minimum, mandatory concepts and their practical implementation: computer systems, programming techniques, programming languages, data structures. The article also presents the actual trends in the evolution of the database systems, in the context of economic informatics.database systems - DBS, database management systems â DBMS, database â DB, programming languages, data models, database design, relational database, object-oriented systems, distributed systems, advanced database systems
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