Research On IFC-Oriented Extending Model And Data Format Conversion

With the proposition and promotion of the concept of information construction,the research on the design,construction,modeling and management of information systems in construction industry is more and more.Especially after the building information modeling(BIM)technology has been developed,the construction unit can improve the construction efficiency bigly by using this technology.They can also save the construction resources and finish the construction by planning at the same time.As an important part of the construction project,construction cost mainly to control the cost of construction projects.So far,quantity bill method,which used in international,can be modeled by using BIM.But the metadata information which makes the model cannot meet the fixed pricing method which our country used in construction cost.What’s more,with the development of mobile information technology,it will be a trend that the building information is used in the mobile device modeling and applications.But the study on how to convert the existing ifcXML format into its responding mobile data format is still rear.In this thesis,we will transform the international bill of quantities pricing method metadata model into the fixed pricing method metadata model which conforms to our country’s quota method by through expansion mechanism of Industry Foundation Class(IFC)standard and find a method to transform XSD into its corresponding JSON Schema by analyzing the ifcXML and mobile data format.There are three main works of this thesis:(1)Studying the international bill of quantities method metadata model.Firstly,we will make sense of the structure of the information model by analyzing the whole structure and the root class entity of the IFC standard.Then,we introduce the six sub-models of the construction cost model one by one,according to the definition and composition of the metadata model,and present their structure by pictures.(2)Creating the quota pricing metadata information model.By researching the IFC standard model extending mechanism,we can extend the quantity bill method metadata model by adding the entities and attribute sets.The new extended model can meet the requirements of China’s quota method metadata information model.(3)Designing the data format conversion mechanism from XSD to JSON Schema.We can create the corresponding conversion dictionary from XSD to JSON Schema about their data types by studying their data formats.And then,we will design a conversion mechanism to translate XSD to its responding JSON Schema.The conversion mechanism will be verified by some test.As the construction industry is required to be with information,it is needed to create a construction cost metadata model which is suit for our country’s method.Because of the different division of particle size,we can just create a quota pricing metadata information model on the base of quantity bill method.While,a conversion mechanism to translate XSD to its responding JSON Schema format is also meaningful in the mobile era,which can directly make sure the data format is right when the XML is translated into JSON.