A Method for Ontology Module Extract

In semantic Web, extensive reuse of existing large ontology is one of the central ideas of ontology engineering. Ontology extraction should return relative sub-ontology that covers some sub-vocabulary. The efficiency of the existing ontology extraction algorithm is relatively low when they try to get a suitable ontology module from ontology at run time. This paper proposed a kind of ontology module extraction method. Related concepts and criterions of ontology modules extraction are studied; data structures and identification and evaluation methods of ontology module extraction are discussed; preliminary experimental results and the corresponding analysis are also shown.

Reliability Analysis of Plug Door System Based on Dynamic Fault Tree

The plug door system is an important guarantee of the safe operation of the emu, since it has structural redundancy, correlation function and fault dynamic characteristics, this paper uses the dynamic fault tree analysis method for reliability analysis. In deep understanding of the basis of the structure and working principle of the plug door, dynamic fault tree model is established by the way of structure ontology, Module iteration is introduced , and the Markov method is adopted to solve the reliability. At the last, we obtained the equipment failure rate and the reliability of the whole system.

A Method of Extracting Ontology Module Using Concept Relations for Sharing Knowledge in Mobile Cloud Computing Environment

In mobile cloud computing environment, the cooperation of distributed computing objects is one of the most important requirements for providing successful cloud services. To satisfy this requirement, all the members, who are employed in the cooperation group, need to share the knowledge for mutual understanding. Even if ontology can be the right tool for this goal, there are several issues to make a right ontology. As the cost and complexity of managing knowledge increase according to the scale of the knowledge, reducing the size of ontology is one of the critical issues. In this paper, we propose a method of extracting ontology module to increase the utility of knowledge. For the given signature, this method extracts the ontology module, which is semantically self-contained to fulfill the needs of the service, by considering the syntactic structure and semantic relation of concepts. By employing this module, instead of the original ontology, the cooperation of computing objects can be performed with less computing load and complexity. In particular, when multiple external ontologies need to be combined for more complex services, this method can be used to optimize the size of shared knowledge.

Study on Small Power BLDCM Drive System

According to the voltage balance equation, the paper deduces the mathematical model of BLDCM on the basis of analyzing the operation principle. In SIMULINK environment, the BLDCM ontology module is built by adopting the combination of BLDCM state equation with S function method. The built motor ontology module proves to be accurate and reasonable through the analysis of the simulation waveform, which helps to analysis BLDCM electronic commutation, etc. Again taking LM621N as commutation control chip, using PIC microcontroller output variable frequency square wave, and through external input device to adjust the square wave frequency, thus realizes the control of motor speed. A brushless dc motor drive with circuit protection functions is designed by the method of combining hardware and software. Not only the motor work situation of ontology is intuitively reflected, and the development cycle is shorted.