Global Positioning System Reference
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spreadsheet for deaths (Fig. 3c) since it is organized in sections according
to each district and female/male distributions.
From the available shape fi les we have chosen several distributions
existing in Costa Rica; however, for the purpose of this chapter we only
present two spatial representations related to administrative distribution
in district, counties, and provinces, as well as health areas. Due to the lack
of mandatory nationwide standards and data governance initiatives in
institutions responsible for generating spatial data, available shape fi les
present many inconsistency problems that must be faced and corrected. The
integration, cleaning, and transformation processes require the specialized
knowledge in geo-informatics and the use of tools that facilitates this
endeavor.
Development of a Spatial Data Warehouse and Spatial OLAP
The requirements expressed by users as described in the previous section,
guided us to develop a SDW based on a multidimensional model that is
able to represent changes in time and facilitates the SOLAP cube creation
for dynamic data manipulation and aggregation. The development of a new
system consists of several steps. Firstly, we refi ne requirement specifi cation
considering available data and user interests. Based on that, we created
a SDW and developed the necessary ETL processes to clean, integrate,
transform, and load data. Afterwards, the SOLAP cubes were implemented
and a front-end application installed and confi gured for the manipulation
of these cubes.
Creation of a Spatial Data Warehouse
The SDW implementation, similar to DWs, requires several phases: (1)
requirements specifi cation, (2) conceptual design, (3) logical design, and
(4) physical design (Malinowski and Zimányi 2008).
Requirement specifi cation
For requirements specifi cation different methods exist (e.g., Golfarelli and
Rizzi 2009; Guo 2006; Mazón et al. 2007; Malinowski and Zimányi 2008):
(1) analysis/goal/user-driven which considers the business and/or user
demands, (2) source/data/supply-driven which focus on the existing
data provided by source systems, and (3) combination of both. Since our
system is currently relatively small and users rely on the incremental
development according to the acceptance of the system by outsiders, the
CCP representative clearly specifi ed foci of analysis that must be handled
fi rst and delivered the data needed for implementation as explained in the
previous section.
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