An ontology for integrated machining and inspection process planning focusing on resource capabilities

The search for and assignment of resources is extremely important for the efficient planning of any process in a distributed environment, such as the collaborative product integrated development process. These environments require a degree of semantic interoperability, which currently can only be provided by ontological models. However, the ontological proposals centred on Resources for Machining and nspection Process Planning have a limited reach, do not adopt a unified view of machining and inspection, and fail to express knowledge in the manner required by some of the planning tasks, as is the case with those concerned with resource assignment and plan validation. With the aim of providing a solution to these shortcomings the manufacturing and inspection resource capability (MIRC) ontology has been developed, as a specialist offshoot of the product and processes development resources capability ontology. This ontology considers resource capabilities to be a characteristic of the resource executing any activity present in an integrated process plan. Special attention is given to resource preparation activities, due to their influence on the quality of the final product. After describing the MIRC ontology, a case study demonstrates how the ontology supports the process planning for any level, approach or plan strategy.This work has been possible thanks to the funding received from the Spanish Ministry of Science and Education through the COAPP Research Project [reference DPI2007-66871-C02-01/02].Solano García, L.; Romero Subirón, F.; Rosado Castellano, P. (2016). An ontology for integrated machining and inspection process planning focusing on resource capabilities. International Journal of Computer Integrated Manufacturing. 29(1):1-15. doi:10.1080/0951192X.2014.1003149S11529

Advances in instrumentation : proceedings of ISA Conference and Exhibit.

Issued in parts

Cavitation and Head Loss Characteristics in Non-symmetric Bifurcations

Nonsymmetric bifurcations, commonly used in piping systems to divert flow from one pipe to another, see considerable use in hydroelectric power applications and low-level outlet works at dams. Under normal operation, cavitation at the bifurcation likely is not an issue; however, during emergency releases for dam safety or other extreme flows, the bifurcation must be able to safely pass the required flows without incurring damage attributable to cavitation. Although nonsymmetric bifurcations are widely used, the authors are unaware of any published data on related cavitation characteristics. The current study used computational fluid dynamics in conjunction with a physical model to predict conditions that would cause the onset of cavitation and to calculate head loss coefficients. Operating conditions are recommended that will allow bifurcations to operate within safe limits of cavitation. This study, although not exhaustive, provides previously unavailable data and can help designers and operators better understand the hydraulic performance of bifurcations