SDI Convergence - Nederlandse Commissie voor Geodesie - KNAW
SDI Convergence - Nederlandse Commissie voor Geodesie - KNAW
SDI Convergence - Nederlandse Commissie voor Geodesie - KNAW
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the tool is deployed more widely users will need individual registration and login before<br />
they can add model instances; in this case the instance will then inherit their personal<br />
details automatically. This is not currently the case. Figure 4 shows more detail of a<br />
model instance.<br />
The administrative elements contained within the system are shown in Figure 6. Several<br />
role based tiers of security are currently supported and this controls access to specific<br />
functions. Additionally the system supports some elements of model governance<br />
(although this requires further development) allowing model developers to record and<br />
communicate endorsement levels and/or development stages for registered models.<br />
5.<br />
EVALUATION<br />
Following<br />
the initial discussions to develop the MIKE system the prototype was built. To<br />
date the evaluation of the product has been limited to one workshop and a number of<br />
one-to-one interviews. This process has revealed a range of areas for further development<br />
and also highlighted a number of issues. For instance one significant requirement<br />
is to link the model metadata to a data register to identify gaps in existing data so that<br />
this can inform model choice and understanding of the resources required for application<br />
of the model. However, not all models have fixed data inputs and consequently this<br />
some-what confounds and complicates design of the interface. Another issue is that<br />
some models contain component models (models within models). At this point although<br />
MIKE allows storage of parent child relations between models this is currently a simple<br />
implementation and needs improvement.<br />
A simple analysis of the strengths and weaknesses of the prototype based on feedback<br />
received to date indicates the following. In terms of ease of use and intuitiveness, parts<br />
of the system are easy to use especially the component supporting registration of<br />
model instances. In particular the implementation allowing the rapid spatial registration<br />
and query of an instance is somewhat unique. The system supports storage of metadata<br />
for a model, its versions and the instances of application. In concept this is similar<br />
to the three level hierarchy described in Gangsheng et al. (2008). By volume, the bulk<br />
of the model metadata currently in the system describes the base models. Unlike<br />
model instance information this is currently cumbersome and time consuming to enter<br />
in the prototype. This is a key weakness and further research and improvement to the<br />
design of this component of the interface is required. Additionally, refinements to the<br />
design of the underlying data structures to support this will also be required. Systems<br />
like NASA GCMD (2009) provide good insight and guidance for this work. At the back<br />
end the metadata model currently appears (based on user feedback) to store the bulk<br />
of the requisite information to support model discovery and use, but provides little support<br />
for the storage of metadata to support on-line model services and automation. This<br />
intentional gap and weakness will be addressed in the future and will benefit from rapid<br />
advances occurring in metadata design for interoperability. Another major weakness<br />
and threat to the prototype is that current spatial data Metadata repositories and services<br />
contain deficiencies in the design, implementation and level of content in respect<br />
to storage and delivery of metadata about data quality. This generally confounds the<br />
ability to meaningfully link model metadata to existing data registration services and<br />
understand data gaps and deficiencies in support of the use of models.<br />
Although<br />
aspects to support model governance have been included in the design of the<br />
prototype we have found that the present interest in these features has not been widespread.<br />
We suspect this is due to cultural factors more than system design and implementation.<br />
Further evaluation is required.<br />
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