Page 1 of 2 Next  Chanin Tinnachote Department of Survey Engineering, Chulalongkorn University, Bangkok Chanin.Ti@chula.ac.th Tanya Teerasarn ESRI (Thailand) Co., Ltd. Geospatial metadata are very important as they document the geospatial datasets and facilitate access, dissemination, and uses of those valuable assets. In Thailand, metadata for geospatial datasets are considered to be a major prerequisite for the development of our National Spatial Data Infrastructure (NSDI). Recently, the International Standard for Geographical metadata, ISO19115, has been adopted as the Thai Industrial Standard 19115. This has intensified the attention of all members of Thailand GIS community in the contents and the practical implementation of this ISO19115. There is also a certain requirement to develop a national standard for geospatial metadata, based on ISO19115, which suit the situation in Thailand. Metadata facilitates the access, dissemination, and uses of those geo-spatial datasets as valuable assets. Metadata becomes even more imperative considering the existing trend toward an explosion of available geodata sets that resulting from the fact that numerous organizations have matured from building to using their geographic databases as well as making them publicly available to others. Availability of good metadata, along with the recent advances in network computing (more commonly known as the information superhighway), is helping to accelerate spatial data sharing (ESRI, 1995). Considering the abundant items of metadata possibly required to describe a geo-spatial dataset, it is also very important that metadata information be constructed and conveyed in such a way that it is understandable to the users. To facilitate exchange and accurate transmission of metadata information between data producers and data users, a number of standards have been developed and implemented. The standard will also ensure that all relevant information is documented for each type of geo-spatial data. In Thailand, the Thai Industrial Standard Institute has recently declared the TIS19115 based on the ISO19115. This implies that all Thai state agencies must create their metadata following ISO19115. Although this TIS19115 can be considered as the National standard for Thailand in the moment, there is still an awareness that the requirement for the development of a National profile of ISO19115 to fit the unique situation and requirement of Thai users. The concept of geo-spatial metadata had been introduced to Thai GIS user communities a number of years ago, as an important part of the National Spatial Data Infrastructure (Tinnachote, 2000). Despite the wide spread awareness of the importance of metadata in Thailand, still only a relatively few number of geo-spatial metadata were created. One of the main obstacles is the lack of a clear understanding on all those metadata items and how to choose the more important items to spend their limited resources into. ISO19115 has identified the mandatory metadata items along with those items which are conditional and optional. The mandatory items specified are, however, considered by most of Thai users to be insufficient for conveying the necessary information about their datasets. Major question for them is which other optional metadata items should be picked and filled up. This paper reveals the result of the study conducted by Teerasan (2006) which has prioritized the metadata items in ISO19115 based on the requirements and the filling up abilities of Thai GIS data producers and users. Table 1. Importance scores classification scheme
Table 2. Filling-Up scores classification scheme
Study of Users' Opinions on ISO19115 Teerasan (2006) has conducted a study based on users’ opinions over the importance of metadata items and the abilities to fill up each metadata items. The users' opinions were acquired using questionnaire together with interviewing. About fifty organizations involved in geo-spatial data production and uses were identified and selected as the Metadata user organizations for the study. Certainly, there is no pure data producer or data user organization. Data producer organizations also use geo-spatial data from other agencies, while data user organizations somehow produce some new datasets may be as results from data manipulation or analysis. The personnel who is responsible for, or is working closely with, metadata activities in each agency was chosen as the interviewee. The questionnaires have two parts of questions. Part 1 contains questions on general information related to Metadata activities in organization. In this part, the interviewees were asked to identify the degree of knowledge they have on geo-spatial metadata in general and their comprehension about the specification in ISO19115 in particular. They were also asked to state their organization's policy, plan, and status on metadata creation and dissemination activities. Final question in this part asks users what type of support they may want in order to create metadata conforming to ISO19115. In part 2 of the questionnaires, the interviewees were asked to express their opinion about the metadata items specified in ISO19115. Among those, there are two questions that make available the important information for the development of our National Metadata standard. The first question asked was to specify, for each ISO19115 metadata item, whether they can or can not fill up that item for their geo-spatial dataset. The second question asked was to give a score for each metadata item based on its importance. Other questions in this part are about the users' general and special requirements related to ISO19115 such as the sufficiency of metadata items provided by the standard and the additional item required.
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