Abstract

Abstract
Actuators based on electroactive polymers are increasingly used in applications including microelectronic devices and artificial muscles, demanding low voltage operation and controllable switching response. This work reports on the preparation of electroactive actuators based on poly(vinylidene fluoride) (PVDF) composites with 10, 25, and 40 wt% N,N,N-trimethyl-N-(2-hydroxyethyl) ammonium bis(trifluoromethylsulfonyl)imide ([N-1 1 1 2(OH)][NTf2]) and 1-Ethyl-3-methylimidazolium Ethylsulfate ([C(2)mim][C2SO4]) ionic liquids (ILs) prepared by solvent casting. Independent of the IL type, its presence leads to the crystallization of PVDF in the piezoelectric beta-phase. The degree of crystallinity and electrical conductivity of the samples strongly depends on ILs type and content. The highest electrical conductivity was found for PVDF/IL composites with 40 wt% of [N-1 1 1 2(OH)][NTf2]. The strain displacement and bending of the PVDF/IL composites were evaluated as a function of IL type and content under applied peak voltages of 2.0, 5.0, and 10.0 V at a frequency of 10 mHz. Strain displacement of the actuators depends more on IL content than on IL type, and the best strain bending response was found for the PVDF/IL composite with 25 wt% of [N-1 1 1 2(OH)][NTf2] at 5.0 V. Further, it is shown that [C(2)mim] [C2SO4]/PVDF composites do not show cytotoxic behavior, being suitable for biomedical applications.

Abstract
The work described in this paper address the problems of productivity of Grohe's Portugal grinding/polishing department, related to the frequent stops of robotic cells for on-line programming and program adjustments. The solution to the stated problem was achieved through the adoption of off-line programming as an alternative to the conventional on-line method. Efforts were developed to overcome some limitations and restrictions found in terms of the software applications used, in order to adapt and improve their use to the needs of this type of contact applications. The solution developed is currently used for off-line programming the grinding robots at Grohe Portugal, with a significant reduction in the cells stop time to program the robots and also in the cycle time. The application of the off-line programming method and of the new programming techniques allowed to obtain a reduction of the cell stop time (up to 85% reduction), to optimize the production cycle time (up to 10% reduction) and, simultaneously, good results in terms of product finishing. The main limitations faced are the lack of realism of the wheel flexibility and the lack of sensitivity of the contact force with it.

Abstract
Purpose - In collaborative settings, such as research and development projects, obtaining the maximum benefit from knowledge management systems depends on the ability of the different partners to understand the conceptualisation underlying the system's knowledge organisation. This paper aims to show how information/knowledge organisation in a multi-organisation project can be made more effective if the domain experts are involved in the specification of the systems semantic structure. A particular aspect is further studied: the role of conceptual relations in the process of collaborative development of such structures. Design/methodology/approach - An action-research approach was adopted, framed by a socio-semantic stance. A collaborative conceptual modelling platform was used to support the members of a research and development project in the process of developing a lightweight ontology aiming at reorganising all the project information in a wiki system. Data collection was carried out by means of participant observation, interviews and a questionnaire. Findings - The approach to solve the content organisation problem revealed to be effective both in the result and the process. It resulted in a better-organised system, enabling more efficient project information retrieval. The collaborative development of the lightweight ontology embodied, in fact, a learning process, leading to a shared conceptualisation. The research results point to the importance of the elicitation of conceptual relations for structuring the project's knowledge. These results are important for the design of methods and tools to support the collaborative development of conceptual models. Originality/value - This paper studies the social process leading to a shared conceptualisation, a subject that has not been sufficiently researched. This case study provides evidence about the importance of the early phases of the construction of ontologies, mainly if domain experts are deeply involved, supported by appropriated tools and guided by well-structured processes.

Abstract

Abstract