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Regarding programmable logic controller (PLC) development, improving programming efficiency and encouraging code exchange and software reuse are necessary to increase the productivity and safety of smart manufacturing and industrial automation. However, differences between implementations are significant even though all manufacturers claim to conform to the IEC 61131-3 and IEC 61131-10 standards, resulting in incompatibilities inside heterogeneous systems, preventing projects from interoperating between vendors. In this article, we present an approach that utilizes an ontology-based semantic model named OntoPLC to enable automatic porting of PLC projects between development environments and also prevent significant information loss during the translation process. High-level semantics of PLC projects are added into OntoPLC including software resources, which can be required for software reuse leveraging semantic query. To demonstrate the usefulness of the ontology model, the proposed methodology is applied to a turbine-driven boiler feed pump control module. [ABSTRACT FROM AUTHOR]

Many types of heterogeneous CAD models created by previous product development activities are stored in enterprise databases. Searching reusable CAD models for engineer design requirements is still very difficult. In this paper, we propose an ontology-based semantic retrieval approach for heterogeneous 3D CAD models by using semantic web theory and information retrieval theory. By exploiting layered feature ontology and ontology mapping, a uniform description for heterogeneous CAD models is generated as semantic descriptor. Meanwhile, to improve the representative ability, several heuristic rules are constructed with the aid of SWRL language and ontology reasoning is acted on the semantic descriptors, which makes our retrieval system achieve better performance. Furthermore, multi-mode similarity measurement is carried out to meet engineers’ diversified requirements. We demonstrate the feasibility and effectiveness of our approach through experiments on heterogeneous 3D CAD model library. [ABSTRACT FROM AUTHOR]

Design rationale (DR) is an important part of design knowledge. Effective reuse of DR depends on its successful retrieval. In this paper, an approach for structured DR retrieval using ontology-aided indexing is presented. Firstly, an ontology-based semantic model of DR is developed based on the extended IBIS-based DR representation in order to effectively utilise the semantics embedded in DR. Then, an ontology-aided indexing method is proposed to build indexes for DR records to index the semantic concepts and relationships in DR. Furthermore, three kinds of query modes are developed to support flexible querying, among which natural language input query and DR record-based query have much more semantics and thus lead to better retrieval results. Finally, a prototype system is implemented. Experimental results show the effectiveness of the proposed approach. [ABSTRACT FROM PUBLISHER]

How to quickly, accurately retrieve and effectively reuse 3D CAD models that conform to user's design intention has become an urgent problem in product design. However, there are several problems with the existing retrieval methods, like not being fast, or accurate, or hard to use. Hence it is difficult to meet the actual needs of the industry. In this paper, we propose a 3D CAD model retrieval approach that considers the speed, accuracy and ease of use at the same time, based on sketches and unsupervised learning. Firstly, the loop is used as the fundamental element of sketch/view, and automatic structural semantics capture algorithms are proposed to extract and construct attributed loop relation tree; Secondly, the recursive neural network based deep variational autoencoders is constructed and optimized to transform arbitrary shapes and sizes of loop relation tree into fixed length descriptor; Finally, based on the fixed length vector descriptor, the sketches and views of 3D CAD models are embedded into the same target feature space, and k -nearest neighbors algorithm is adopted to conduct fast CAD model matching on the feature space. In this manner, a prototype 3D CAD model retrieval system is developed. Experiments on the dataset containing about two thousand 3D CAD models validate the feasibility and effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]