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Research on Application of the Method-Metadata in Resources & Environment Information System
Jiantao Bi, Tianhe Chi, Xintong Li, Yanrong Cao, Hongqiao Wu, Jianbang He
Institute of Geography Sciences and Natural Resources Research (IGSNRR),
Chinese Academy of Sciences (CAS),
Beijing 100101,P.R.China
Jiantao Bi, Tianhe Chi, Xintong Li, Yanrong Cao, Hongqiao Wu, Jianbang He
Institute of Geography Sciences and Natural Resources Research (IGSNRR),
Chinese Academy of Sciences (CAS),
Beijing 100101,P.R.China
1.Introduction
With the everlasting renewal of technology and research approach, the study to the earth we live on has been deepened continually, which accumulates lots of information; moreover the development of Geographical Information System (GIS )in recent years ,especially the acquisition and processing technology of remote sensing data with multi-sources, multi-spectra, multi-bands and multi-resolutions, provides a great deal of resources and environment information which make it possible for us to change and take advantage of the environment. Because these enormous data cannot be deciphered, read and used them to make decision directly, only can they be useful after the analysis by the appropriate mathematic model and method. It is so difficult how to find out a proper model and method through which the resources and environment information we got can be analyzed to obtain the valuable result. The metadata can be a feasible solution to this problem.
2.The definition and characteristics of Method-Metadata
According to the constitution of REIS, the system metadata could be divided into 3 categories: Data-Metadata Class, Model-Metadata Class, and Method-Metadata Class. The Fig. 1 shows the static structure of REIS metadata in UML.
Figure 1 The Static Structure of REIS Metadata in UML
As for the Data-Metadata Standards shown in Fig. 1, the study at present is more, and it is also comparatively perfect. For example, the organizations such as ISO/TC211, FGDC have established a variety of metadata standard 46. Accordingly, there are also many services of geographical information Data -Metadata such as Clearing house Information Infrastructures etc. As for the Model-Metadata standard, it can be refer to the relevant document?3?. This paper mainly focuses on the discussing of Method-Metadata.
2.1 Definition of Method-Metadata
The main purpose of data-sharing is to make people query the information they need timely, analyze them and get the corresponding results, so that the expenditure can be saved and the efficiency can be improved. As a result, REIS should provide not only all kinds of data for sharing but also the services convenient for clients to use the data reasonably and effectively. The methods can be resolution for this problem.
Method is that by using technology or implements, it can resolve some problems we care about. When people encounter the problem hard to settle directly, they tend to resolve it indirectly by other instruments. Method is of great importance to the development and advancement of human society. REIS has integrated many implication methods such as ALP, Clustering Analysis, and Gray System, Heredity Algorithm etc. It is necessary for us to establish Method-Metadata for the sake of the convenience of clients to analyze and evaluate these data.
Method-Metadata is the describing information about method. It is used not only to explain the problems each method encounters and the applicable range and so on, but also manage and index the methods in system. Indexing this kind of metadata, clients can quickly browse, look up the relevant methods and know their purposes, using conditions or something like that in order to take advantage of them effectively.
The virtues of introducing Method-Metadata are as follows :
2.2.1 Method-Metadata and Data-Metadata
Data-Metadata refers to the metadata, which is used to manage and index the data and dataset in the REIS, while Method-Metadata is the description about the methods, so their researching objects are difference. But through some data interfaces, such as MD_method parameter class, the Method-Metadata can interchange with the Data-Metadata and operate the dataset together.
2.2.2 Method-Metadata and Model-Metadata
There are differences as well as relationships between Method-Metadata and Model-Metadata. The main relationship is that Model and Method-Metadata are both serve for the Data-Metadata in order to realize the sharing and analyzing of the integrated information, while the differences between them are as following:
Figure 2 Structure Relationship between Model-Metadata and Method-Metadata
According to the Fig. 1, the Method-Metadata class inherited from the metadata class which is defined by the ISO. With the relationship between Method-Metadata and data, Model-Metadata, as well as the series attributes the Method-Metadata has, it can describe and search for the difference methods in the REIS.
3. Standard Framework’s Structure of Method-Metadata
The static structure figure of Method-Metadata in UML is showed as Fig. 3.
Figure 3 Static Structure of Method-Metadata in UML
According to Fig. 3, seven different classes as following aggregate the Method-Metadata class in REIS:
The research on the database creation and data sharing of National Resource and Environment is a great foundation research project in the CAS. The designing and application of the metadata management tools software, which is based on the integrating style in the network, is an important part in this project. This software is constructed with the Client/Server system, which has the thin client merit, and operates the meta-database of the database server in the system. After finished the identity confirmation in the user’s identity management system, the user can login in this system, searching and analyzing the Method-Metadata freely. The user can also use the analysis and the evaluation method tool package to analyzing data directly. The integration and application of the Method-Metadata in REIS is shown as Fig.4.
Figure 4 Integration and Application of the Method-Metadata in REIS
5.Conclusion
It is obvious that it will promote the efficient of the information by using the metadata management tools in this paper, and the Method-Metadata to search the methods in REIS. There is little report about the Method-Metadata in the world, and we hope to find a new way in the metadata application in order to serve the information sharing better.
Reference
With the everlasting renewal of technology and research approach, the study to the earth we live on has been deepened continually, which accumulates lots of information; moreover the development of Geographical Information System (GIS )in recent years ,especially the acquisition and processing technology of remote sensing data with multi-sources, multi-spectra, multi-bands and multi-resolutions, provides a great deal of resources and environment information which make it possible for us to change and take advantage of the environment. Because these enormous data cannot be deciphered, read and used them to make decision directly, only can they be useful after the analysis by the appropriate mathematic model and method. It is so difficult how to find out a proper model and method through which the resources and environment information we got can be analyzed to obtain the valuable result. The metadata can be a feasible solution to this problem.
2.The definition and characteristics of Method-Metadata
According to the constitution of REIS, the system metadata could be divided into 3 categories: Data-Metadata Class, Model-Metadata Class, and Method-Metadata Class. The Fig. 1 shows the static structure of REIS metadata in UML.
Figure 1 The Static Structure of REIS Metadata in UML
As for the Data-Metadata Standards shown in Fig. 1, the study at present is more, and it is also comparatively perfect. For example, the organizations such as ISO/TC211, FGDC have established a variety of metadata standard 46. Accordingly, there are also many services of geographical information Data -Metadata such as Clearing house Information Infrastructures etc. As for the Model-Metadata standard, it can be refer to the relevant document?3?. This paper mainly focuses on the discussing of Method-Metadata.
2.1 Definition of Method-Metadata
The main purpose of data-sharing is to make people query the information they need timely, analyze them and get the corresponding results, so that the expenditure can be saved and the efficiency can be improved. As a result, REIS should provide not only all kinds of data for sharing but also the services convenient for clients to use the data reasonably and effectively. The methods can be resolution for this problem.
Method is that by using technology or implements, it can resolve some problems we care about. When people encounter the problem hard to settle directly, they tend to resolve it indirectly by other instruments. Method is of great importance to the development and advancement of human society. REIS has integrated many implication methods such as ALP, Clustering Analysis, and Gray System, Heredity Algorithm etc. It is necessary for us to establish Method-Metadata for the sake of the convenience of clients to analyze and evaluate these data.
Method-Metadata is the describing information about method. It is used not only to explain the problems each method encounters and the applicable range and so on, but also manage and index the methods in system. Indexing this kind of metadata, clients can quickly browse, look up the relevant methods and know their purposes, using conditions or something like that in order to take advantage of them effectively.
The virtues of introducing Method-Metadata are as follows :
- To quickly index and locate the methods.
- To analyze all methods in a certain field to find the most suitable one, and to realize the optimum organization of those methods.
- To effectively resolve the problem” Difficulty convincing potential Metadata providers of the benefits of contributing Metadata. e.g. no link from supplying Metadata and increased revenue” (6), which will protect the copyright and patent of methods, and realize the calculation of the runoff and expenditure of metadata quotation.
- To share the knowledge and information more effectively. Everyone or every organization, who may be good at some professional field but not clear to the methods in the other fields, and when they need use them to research, can use Method-Metadata to resolve the problem.
2.2.1 Method-Metadata and Data-Metadata
Data-Metadata refers to the metadata, which is used to manage and index the data and dataset in the REIS, while Method-Metadata is the description about the methods, so their researching objects are difference. But through some data interfaces, such as MD_method parameter class, the Method-Metadata can interchange with the Data-Metadata and operate the dataset together.
2.2.2 Method-Metadata and Model-Metadata
There are differences as well as relationships between Method-Metadata and Model-Metadata. The main relationship is that Model and Method-Metadata are both serve for the Data-Metadata in order to realize the sharing and analyzing of the integrated information, while the differences between them are as following:
- The model, which is the object of the Model-Metadata, is mainly used to simplify the real world’s problem by abstraction, so that it can serve for the people to analysis the problem well. It may not give some methods through which may solve some specific problems, such as sand plate model, hydrological model. On the other hand, the method, which is the object of the Method-Metadata, is to give the steps to solve some model and problems and get the results of them.
- The Model-Metadata may be corresponding to many methods in the Method-Metadata, that is to say that one model may have many solving methods, such as: in the environment assessment model, we may use AHP Analysis Hierarchy Progress , plurality regression analysis methods to resolve the same model. As for a method, it can be used in different models, which belong to various fields. The relationship between Model-Metadata and Method-Metadata is shown as Figure 2.
Figure 2 Structure Relationship between Model-Metadata and Method-Metadata
According to the Fig. 1, the Method-Metadata class inherited from the metadata class which is defined by the ISO. With the relationship between Method-Metadata and data, Model-Metadata, as well as the series attributes the Method-Metadata has, it can describe and search for the difference methods in the REIS.
3. Standard Framework’s Structure of Method-Metadata
The static structure figure of Method-Metadata in UML is showed as Fig. 3.
Figure 3 Static Structure of Method-Metadata in UML
According to Fig. 3, seven different classes as following aggregate the Method-Metadata class in REIS:
- Identification Including: method’s name, the abstract description of the theory, the origination of the method, the store location of some code about the method realization and the contact information, MD_Method Metadata may aggregate one or more Identification classes.
- Adaptation Scope Including: the application fields of methods, the adaptation scope of the method’s results, and the error of the method’s solutions. MD_Method Metadata may aggregate one or more Adaptation Scope classes.
- Parameter of Method Including: the input parameter set and the output parameter set which the method needs; the meaning of the input and output parameters; the value’s effective digits of the input and output parameter. MD_Method-Metadata may aggregate one or more Parameter of Method classes.
- Running Condition Including: the operation environment of method realization, such as all kinds of soft and hard environments, equipments, method’s program code and the version and status of the program. MD_Method-Metadata may aggregate zero or more Running Condition classes.
- Management Information Including: the brief introduction of the method’s founders; the name, address, contact information of the programming person of the methods, the copyright and the usage information of the program. MD_Method Metadata may aggregate zero or one Management Information classes.
- Method’s Resolution Including: the error’s level of the method result; the effective digits of input parameter and result. MD_Method Metadata may aggregate zero or more Method’s Resolution classes.
- Method Instance Including: the application purpose of the method, the realization code of the method, the resolution process and the result description of the method. MD_Method Metadata may aggregate one or more Method Instance classes.
The research on the database creation and data sharing of National Resource and Environment is a great foundation research project in the CAS. The designing and application of the metadata management tools software, which is based on the integrating style in the network, is an important part in this project. This software is constructed with the Client/Server system, which has the thin client merit, and operates the meta-database of the database server in the system. After finished the identity confirmation in the user’s identity management system, the user can login in this system, searching and analyzing the Method-Metadata freely. The user can also use the analysis and the evaluation method tool package to analyzing data directly. The integration and application of the Method-Metadata in REIS is shown as Fig.4.
Figure 4 Integration and Application of the Method-Metadata in REIS
5.Conclusion
It is obvious that it will promote the efficient of the information by using the metadata management tools in this paper, and the Method-Metadata to search the methods in REIS. There is little report about the Method-Metadata in the world, and we hope to find a new way in the metadata application in order to serve the information sharing better.
Reference
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- Jiantao Bi, Hongqiao Wu, Yanrong Cao, Yuxia Huang, Tainhe Chi, Jianbang He, Research on the Model and Method-Metadata in Resources & Environment Information System and theirs Iintegration, Geo-Information Science, 2002.6
- Yanrong Cao, Hongqiao Wu, Jiantao Bi. The Research of Metadata Management of National Resource and Environment Spatial Database. Geo-Information Science.2002
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