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The purpose of this paper is to make research on causing mechanism of meteorological disaster as well as the components of meteorological disaster system and their semantic relationships. It has important practical significance due to the urgent need of further providing support for pre-assessment of influences of disastrous weather/climate events and promoting the level of emergency management.

This paper analyses the occurrence regulations and components of meteorological disasters and proposes the concept of meta-action. Ontology modelling method is adopted to describe the components and relationships among different parts comprising meteorological disaster system, and semantic web rule language is selected to identify the implicit relationships among the domain knowledge explicitly defined in ontology model. Besides, a case is studied to elaborate how to provide logic and semantic information support for comprehensive risk assessment of disastrous weather/climate events based on rule-based ontology reasoning method. It proves that ontology modelling and reasoning method is effective in providing decision makings.

This paper provides deep analyses about causing mechanisms of meteorological disasters, and implements information fusion of the components of meteorological disaster system and acquisition of potential semantic relations among ontology components and their individuals.

In this paper, on the basis of analysing the disaster-causing mechanisms, the meteorological disaster ontology (MDO) model is proposed by using the ontology modelling and reasoning method. MDO can be applied to provide decision makings for meteorological departments.

The aim of this study was to develop a new generation of automatic systems based on cutting-edge design and practical welding physics to minimize downtime caused by defects and machine faults on the barges. Automatic welding has been used frequently on offshore pipeline projects.

An automated welding robot system for sub-sea pipeline installation was constructed. The system utilized the double-car double-torch welding, which is light-weight and compact, suited for offshore applications. Several state-of-the-art technologies were integrated into the control system design, including a heterogeneous network based on EtherCAT technology, network communications based on CANopen, motor synchronization, all-position welding, etc. In addition, the utilization of the CAN bus reduced the number of cable lines and increased the extensibility of the proposed welding robot system. An internal clamp with copper shoes assured a nice root weld and narrow bevel design and the welding efficiency was improved accordingly.

The trial was carried out to verify the rationality and effectiveness of the proposed automated system. The deposition rate of the backing welding could reach 17.78 kg/h; the average time for each welding was 340 s. This system was unique in that it features a dual-torch welding head that allowed for the deposition of one run with twice as much material as a single torch head. The experiment showed that the double-vehicle double-torch mode can greatly improve the welding efficiency of pipeline installation during the welding process.

The automated welding robot system will be applied to offshore pipeline projects.

This robot is the first submarine pipeline installation welding robot to use a heterogeneous network based on EtherCAT technology. Various aspects of the submarine pipeline installation welding robot’s design and performance were discussed, including mechanical body design, control system design and welding process specification.