A NATIONAL GEOGRAPHIC PORTAL
Haim Srebro, Jacob Bar-Lavi and Benny Weiss
Survey of Israel, Tel-Aviv
Israel
haim@mapi.gov.il
Abstract
Since 16 years ago a National GIS was built by the Survey of Israel (SOI) to serve the
government ministries and agencies as well as to support the community of nationwide geospatial consumers.
The data source of the National GIS was based on triangulated aerial photographs
using analytical and digital photogrammetry.
A year ago a new initiative was launched by the Survey of Israel: A National
Geospatial Portal. This portal has been developed in cooperation with the Interagency Committee for GSDI. The prototype of the portal is already working, ready to
be installed before the end of the year. It will be part of the E-Government initiative
and will serve simultaneously as a geospatial portal for the public and a governmental
GIS clearing house. Following a thorough analysis of the options, the decision was
made to build a geospatial data warehouse at the first stage, in order to improve the
quality control of data. This approach was adopted because of the variety of data
sources. Though the quality of data based on the National GIS is very high, one
cannot assure the quality of uncontrolled data coming from all ministries and
agencies, so that integrated applications of the simple end web-user may not meet the
expected standards.
In order not to loose the confidence of the public, and to improve the reliability of the
portal, the warehouse approach will be followed, enabling a change in the future to a
distributed approach like the one implemented by the US geospatial one-stop portal.
Following the resolution of the Inter-agency Committee with reference to the national
geospatial meta-data standard, this standard was adopted for the portal as well.
Meta-data for 400 layers of geospatial data has already been prepared and is
accessible in the system, which operates as of May 2006 in an intranet mode.
The system works quite fast and passed successfully loading simulations. Potential
users are exposed to the portal and are very satisfied with it, including the education
community and potential emergency applications.
The paper elaborates also on the technological environment and tools used for the
project.
The main targets of the geospatial portal
The main target of the portal is to concentrate, to integrate and to distribute geospatial
data following the e-government policy of making the data available to the public.
The second target of the portal is to serve as a clearing house of geospatial data
between governmental offices and thus to save governmental investment and to
improve compatibility and integrativity between governmental offices regarding
geospatial and location based applications.
The expectation is that the exposure of data will also stimulate processes of improving
the quality and precision of the data.
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Organization
The portal is developed and managed by the Survey of Israel and coordinated with the
Inter-Agency committee for geographic information.
A steering committee of the two organizations headed by the Director General of the
Survey of Israel (who chairs the Inter-Agency committee) defines the goals and
confirms the planning. A working team of the committee defines the requirements and
controls their achievement while working teams of the Survey of Israel are
responsible for their execution.
The main components of the system are: data collection, data integration, simple web
operational search mechanisms, national geospatial meta-database, data sharing and
data distribution mechanisms and a variety of links to GIS and mapping web sites.
The portal is planned to be installed on the central governmental web site, using its
services including security of data.
The alternative strategies
The main alternative strategies that were discussed at the design stage of the portal
were:
1. To adopt the technology and architecture of the American GOS (Geospatial One
Stop), which integrates map services, which exist in various offices in the
government, and extracts data using data harvesting technologies supporting the
meta data of the portal.
2. To develop a central system which depends on distributed databases, similar to the
idea of data marts which is common in the IT market. The core idea behind this
alternative is that the governmental offices enable the portal direct accessibility to
their data servers, and the portal engines read the data and present it.
3. To adopt the idea of a geospatial data warehouse (DWH) in which the data,
including the metadata, is concentrated in one database using ETL tools (Extract,
transform and load) for populating and periodically updating the data warehouse.
The following are the advantages and disadvantages of the different strategies:
Strategy
GOS
Data Marts
Advantage
Disadvantages
- The technology was applied in
other countries.
- The investment in development is
relatively small (mainly in the
Hebrew interface).
- There is a tangible application base
for decision-making.
- It fits large countries such as
USA, India, but doubtful for
Israel.
- It depends on the existence of
Map Services in the relevant
organizations.
- No control on cartography.
- At time of decision making the
GOS of ESRI has undergone
changes.
- It will be more difficult to
implement comparing to
DWH due to decentralization.
- Problems of coordination and
- It is philosophically right (A
distributed database).
- Governmental offices do not have
to "depart" from data.
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Data
Warehouse
- Each office is responsible for its
database maintenance. The SOI
will have to invest less.
- Central control of the database and
high application prospects.
- Control of cartographic
presentation, gathering of subjects,
searching, etc.
- The variety of technologies in
governmental offices is not a
restriction.
- Short setting up.
communication.
- Development of complex ETL
engine for loading & updating
is required.
- No direct access to operational
databases.
- SOI responsibility for
maintenance.
- Refusal of governmental
agencies to depart from their
data.
- Difficulty to integrate data
from local government.
Decision and concepts of implementation
For the current stage of the geospatial portal, the decision was to adopt the Data
Warehouse concept. The main reason for it was that the process could be better
controlled, since an initial validation could be made for data, which is imported from
various sources. Thus, not loosing the credibility of the project at the first stage of the
portal, when gaining the confidence of the users is crucial. In addition the core of the
portal, which is the data of the National GIS of the Survey of Israel, already exists and
easily accessible since the project leader is the Survey of Israel. In addition, Israel is a
small country and the access to the data covering the whole country in various
governmental agencies is relatively easy.
Additional resolutions were accepted with regards to the geographic portal:
1. To adopt a simple system for the integration of the presentations of geospatial data
and geospatial data keys. This was accepted due to the decision to begin first with
free access of the public and then to develop the intranet between the
governmental offices.
2. To implement the concept of openness and transparency of the GIS, for the
presentation of a large scale of geospatial data layers free of charge to the public.
3. To concentrate and manage the geospatial meta data in one organization (the
Survey of Israel), implementing a national meta data standard based on ISO.
4. To make use of GIS technologies which already exist in the Survey of Israel
(Using ArcIMS as the map engine, and SDE above the Oracle database).
These resolutions together with the understanding of the initial internet users lead to
the following guiding concepts:
1. Simplicity of use – intuitive operation of the user interface both for
presentation of geospatial data, and for meta data queries and presentation.
2. Attractiveness – clear and convenient user interface and an attractive
cartographic design.
3. Solidity of focusing on applications.
4. Internal standardization – so that the user will feel familiar in any future
environment which will be based on the portal.
5. External standardization – following Windows and Internet standards as well
as Governmental standards.
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6. Protection and license management – including dynamic management of
permissions according to the application of the user.
Data included in the portal
The portal includes about 100 layers of national geospatial data from its early stage of
operation, i.e. main GIS layers that are stored in various governmental offices.
The Portal represents data with great variability and richness that enable the system to
sort the layers under main topics and the user to extract relevant meta data.
The portal is integrative and the data includes many topics, such as basic mapping
(roads, buildings, addresses, orthophoto, contours, hydrology, institutes, various
scales of raster topographic layers etc.), layers of cadastre and planning (blocks, plots,
town plans, master plans, land reserves, etc.), tourist information (national resorts,
national parks, hiking trails, forests, woods, parking areas, etc.), administrative
boundaries, transportation, infrastructure, security and national emergencies.
The portal enables simultaneous presentation of multiple layers of information, with
high cartographic fit, linked to attributed information in various formats according to
the spatial entities.
In addition, and based on the general data in the system, there are engines that enable
links to other databases, that might give specific information in special operative
applications in the future, for internal governmental usage.
The functionality of the portal
As mention above, the portal's concept is to enable its operation by any user,
professional, or random, from various disciplines. With this principle in mind the
tools are divided into two sets: standard tools, which are presented on the main screen,
and advanced tools that are not presented to unskilled users.
A summary description of the tools available in the portal:
1. Ability to present layers of data in any scale on a national map by using the
function of highlighting the layers, and focusing on an area for
increasing/decreasing the scale.
2. Ability to describe data on each item on the map, according to the information that
is linked to the geospatial entities.
3. Easy to use search engine: by name of place, by address (street name and building
number), by block and parcel number, town plan, master plan, names of public
institutions and sites, road number, intersection, national resorts, national parks,
coordinates (central point with radius, window, or polygon), and general string in
all tables of data in the system.
4. Search engine to locate block/parcel according to address and vice versa.
5. A special engine to locate a desirable layer.
6. Dynamic presentation of the legend.
7. Printing maps in any chosen scale.
8. Producing general data reports.
9. Measuring distances and areas on maps.
10. Tools for integrated cross-layers geographical applications.
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11. A choice of using geographic or SQL (dynamic queries generator) tools for map
and A/N data presentations.
12. Copy a map (as a picture) and alphanumeric data from the system to Office
documents.
13. "My map" – a tool to save and send by E-mail all the maps produced in a job
sequence.
14. Search engine for meta data and their representation in tables either as a summary,
or as a detailed report.
In addition, the portal includes an external interface for other operation systems
(general and flexible API with parameters). The interface will have hierarchy tools in
order to establish a preferable job and a manual with examples for the use of API
operation.
The system architecture
Production
Environment
Internet
Government
Offices
Applications
Physical Transfer
Data from Government
and Public
Organizations
SOI
Intranet
Applications
Development
Environment
The meta data component in the geospatial portal
The meta data is an important component in the geographical portal.
The development of the portal is progressing in accordance with the ripening of the
Israeli national geographic meta data standard, as components of the National GIS
standards. These processes are taking place in SOI as part of the operation of the
Inter-agency Committee for GIS. The new meta data standard was approved by the
representatives of the public bodies and the governmental offices, which are members
in the committee, and adopted by the committee.
The development of the meta data component is based on ISO 19115, and was
constructed in a way that will enable its direct feeding to ARC CATALOG (An ESRI
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product), but will be observed (in Hebrew) similarly to other portal components on
commonly used web computers/terminals.
The meta data of the portal component is derived from the new standard, and its data
structure is characterized by few and simple fields.
The meta data component matches the two basic principles of the portal:
centralization of the information in a data warehouse structure, and simple intuitive
operation of its visible parts.
a. Centralization of information in D.W.H.
Both the portal and the meta data follow the concept of D.W.H. that easing the
process of data feeding and strengthening uniformity of data originating from
diverse sources.
b. Simplicity in retrieving meta data.
The presentation of data on the information contained in the geographical
portal is intuitive and simple to operate for any Internet user, including those
that are not experts in geographic sites. The retrieval of data is possible in
several options: by coordinates; by definition of key words; by category
selection (choosing a subject of a scroll table).
All the information in the portal is accessible to the public, with no limitation or a
need of passwords or permits. The meta data of the portal includes around 400 layers
of GIS of countrywide coverage, or of national interest, in spite of the fact that the
information included in the portal includes only a quarter of these layers. The rest of
the layers are not ready for presentation for various reasons: security, intellectual
property, privacy and lack of updated data.
The meta data is delivered to the public in two levels of detailing:
a. A centralized table: including details on each layer with regard to its contents,
to ownership, and to presentation in the Portal.
b. Details of the meta data about the layer, its producer and the owner of the
data, its accuracy level and updating, a sample data and address for
communication including via e-mail.
Cooperation with the education community
We see the education community, including school pupils and university students of
geography, as an important potential promising community of users. Therefore, we
cooperate now with the academic staff as well as the committee for geographic
education, in order to get their focused responses to be integrated and implemented in
the system. On the other hand, the main goal of the cooperation is to integrate the use
of the portal by the pupils and students in their geography classrooms.
This project is considered to be today our most promising one with regard to the
national geospatial database and the more we advance the greater are the expectations
for the benefit of the public.
The requirements of the board of education for the portal in order to fully integrate it
in the learning program are very demanding and can not be met for the initial
launching stage of the portal. They will be taken care of on the long run. For the first
stage the portal will take care of basic geographical education applications.
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Examples of the methodical subjects which were required by the education committee
included regional and urban geography, economical aspects, transportation, social
geography, etc.
The thematic categories of the portal which may support the requirements include:
basic maps, geopolitical expressions including boundaries, landscape, land forms,
climate, population, settlements, infrastructure, environmental aspects, nature hazards,
etc. The targets of the "learning geography package" is to teach the use of GIS tools
and to stimulate the interest of students in geography.
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Summary
After 16 years of building a national geospatial database, the Survey of Israel is
leading a new initiative of a national geospatial portal.
This portal is constructed in coordination with the Inter-Agency committee for GIS.
The data is imported from many government and public organizations to a data
Warehouse. The system has been developed using client/server technology in a web
environment on the basis of the shelf software (ESRI 's ArcIMS). The application is
easy to operate and aimed at first stage to non GIS experts, though maintaining more
advanced geographic analysis tools to be used by experts. The application can be
installed at no cost on any web terminal computer. In addition to serving the public
the portal will serve in the future as a geospatial clearing house in the government.
The exposure of the system to the public is scheduled before the end of the year.
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