Study on Performance of Remanufactured Engine Based on EMD
According to the non-stationary property of vibration signal, the vibration signal is decomposed by empirical mode decomposition (EMD). And this method is applied to study the remanufacturing level of engine. Based on the decomposition of vibration signal, correlation coefficient is introduced to study the correlation between IMF (Intrinsic Mode Function) components and original signal, and dynamic structure of IMF components is analyzed by correlation dimension. In order to study the remanufacturing level of engine, correlation coefficient and correlation dimension are considered in the function of IMF, and an index of vibration intensity is proposed. A corresponding relationship is established between remanufacturing level and vibration intensity. This method has been proved that the running state of engine can be reflected by vibration intensity, and this index can be used to evaluate the remanufacturing level of engine. DOI : http://dx.doi.org/10.11591/telkomnika.v12i1.3896
Cavity Vertex Regeneration through Optimal Energy Model for Restoration of Worn Parts
Restroration of worn parts is a key technique in remanufacturing engineering. It is also a popular research topic in the domain of sustainable manufacturing. To tackle the difficult problem of obtaining a reference model for repair of worn parts, this paper proposed a novel approach to regenerate the vertices over the worn cavity. After a brief description of the repair process, this paper focuses on the optimal energy model establishment. Based on the energy model the vertices of the worn cavity can be regenerated. Error calculation of the vertices recreated to the original model is proposed to search the shortest distance. These algorithms proposed were implemented in the repair system through Visual C++6.0. Several examples of worn parts are presented to illustrate the feasibility of the method. The testing result shows that the vertex regenerated through the optimal energy model can satisfy the requirement of accurate geometry regeneration for repair of worn parts. Finally, conclusions are drawn and further research work is discussed. DOI:  http://dx.doi.org/10.11591/telkomnika.v11i5.2479
Secoiridoids from Olea europaea
Abstract Three new secoiridoids have been isolated from the leaves of Olea europaea along with the previously reported. The compounds were identified by spectral means.